emed scientific meeting 2004 - emed scientific meeting 2006

Transcription

emed scientific meeting 2004
Proceedings
Leeds, UK, Jul. 29 - Aug. 1, 2004
Contents
page
Welcome to Leeds
3
Host, venue, sponsor
4
Organising/scientific committee
5
ESM History
6
novel award 2004
7
The best ESM presentation award
8
The best ESM poster award
8
Activity day
9
Map of Leeds
10
Important Telephone numbers
11
Cultural events in Leeds
11
Meeting overview
12
novel 2004 © NL
ESM2004 Program
Thursday 29.7.2004
13
Friday 30.7.2004
13
Friday 30.7.2004 cont.
14
Friday 30.7.2004 cont.
15
Saturday 31.7.2004
16
Sunday 1.8.2004.
16
Sunday 1.8.2004.cont.
17
Abstracts of presentations, posters
18
emed scientific meeting
Q
29 July - 1 August, 2004
2
Welcome to Leeds
The University of Leeds is celebrating its centenary
year and its founders could not have imagined
what has been created a century later: 33,000
students, a £320M turnover (with a £100M+
research budget) and a vastly expanded estate.
Above all, there is a now a scale of academic
achievement that is second to none. There is much
to celebrate and your participation in the IX emed
scientific meeting is one such occasion.
We return to the UK for the first time since the
inaugural meeting in Liverpool in 1991. For this
Prof. Jim Woodburn
reason we have invited our first host, Professor
Leslie Klenerman to deliver the first keynote presentation: a reflection on the early years on
pressure distribution measurement.
The scientific programme will combine oral presentations from over 30 submitted abstracts, a
poster session and a workshop for novel users. We also have an exciting social program including
an activity day out in the Yorkshire Dales, a visit to the Thackray Medical Museum and the
conference banquet.
Through this forum, I hope we can meet friends old and new and that we all have the opportunity
to advance our knowledge and understanding of the science and application of pressure
distribution measurement.
On behalf of the Academic unit of Musculoskeletal Disease, welcome to Leeds and I hope you have
an enjoyable and productive meeting.
Sincerely,
novel 2004 © NL
Jim Woodburn
Q
3
Host
Leeds university, UK
The 2004 ESM is hosted by the Academic Unit of
Musculoskeletal Disease in the School of Medicine at
the University of Leeds. The University of Leeds
(http://www.leeds.ac.uk/) is acclaimed world-wide for
the quality of its teaching and research. One of the
largest universities in the UK, Leeds is also the most
popular among students applying for undergraduate
courses. An emphasis on innovative research and
investment in high-quality facilities and first-rate
infrastructure means that no fewer than 35 departments
are rated internationally or nationally 'excellent'. Its size
and international reputation enables the University to
offer one of the widest ranges of academic courses in the
UK. During the current academic year over 29,500
students are attached to 670 different first-degree
programmes and 330 postgraduate degree programmes.
A further 52,000 men and women are enrolled on short
courses with the University.
University of Leeds
Leeds University Medical School, founded in 1831, provides high quality medical research and
education. The Academic Unit of Musculoskeletal Disease conducts research in a wide range of
areas including: clinical rheumatology, clinical immunology, immunotherapy, bioengineering and
rehabilitation (http://www.leeds.ac.uk/medicine/units/ms.htm). The unit undertakes a dedicated
program of foot and ankle research with special emphasis on the rheumatic diseases, especially
rheumatoid arthritis. Much of the work is conducted in the gait analysis lab with access to both
novel plate and in-shoe pressure systems. These systems are used for routine clinical assessment
and treatment planning and evaluation and for clinical research into the pathomechanics of foot
disease in the rheumatic disorders. Dr Jim Woodburn has attended the ESM meetings since Penn
State and, along with his co-organiser Debbie Turner, welcomes you to Leeds for the 2004 meeting.
Venue
Weetwood Hall
Weetwood Hall
Otley Road, Leeds LS16 5PS
West Yorkshire, UK
Tel.: +44 (0)113 230 6000
Fax: +44 (0)113 230 6095
novel 2004 © NL
Sponsor
emed scientific meeting ° 29 July - 1 August, 2004
4
Organising Committe
Dr James Woodburn and Deborah Turner,
Academic Unit of Musculoskeletal Disease, University of Leeds.
Telephone: 44 (0) 113 343 4938
Fax: 44 (0) 113 244 5533
e-mail: [email protected]
Scientific Committe
Dr James Woodburn
MRC Clinician Scientist Fellow
University of Leeds
Academic Unit of Musculoskeletal Disease
Dr Philip Helliwell
Senior Lecturer in Rheumatology
University of Leeds
Academic Unit of Musculoskeletal Disease
Dr Roger Soames
Senior Lecturer
University of Leeds
School of Biomedical Sciences
Dr Neil Messenger
Senior Lecturer
University of Leeds
ULISES (University of Leeds Institute for Sport and Exercise)
novel 2004 © NL
Dr Nick Harris
Consultant Orthopaedic Surgeon
General Infirmary at Leeds
Specialist Foot and Ankle Surgeon
Q
5
ESM History
A decade ago novel was approached by Professor Leslie Klenerman to provide support for
development of an emed user group meeting hosted by the University of Liverpool. The inaugural
meeting began the following year in Liverpool. At that time, we did not realize that the emed
meeting would take us half way around the world and the tradition would be carried on into the
next millennium with the 2000 millennium meeting in Munich, Germany. And the 2002 meeting in
Kananaskis, Canada hosted by our friend, Prof. Benno Nigg, head of the Human Performance
Laboratory, University of Cagary.
The Liverpool meeting provided an important exchange of experience and results in pressure
distribution measurements. This was the first step in establishing co-operation between the
emed users and anyone interested in pressure distribution technology. The format of the
meeting through scientific and clinical presentations and workshops was used to define pressure
distribution measuring as more than a "pretty picture".
After the initial meeting, the emed user group meeting became recognized as the emed
scientific meeting welcoming users of all pressure distribution measuring technology and was
scheduled biennially. Since then the meeting has enjoyed the wonderful hospitality of the
following locations: Vienna, Flagstaff, Ulm, PennState and Brisbane, Munich and Kananaskis.
In 1991, the first novel award was presented in recognition of excellence in pressure
distribution research. The novel award recipient was determined by an international review
committee from the fields of biomechanics and medicine. The novel award for pressure
distribution measurement research continues to be endowed by novel.
novel 2004 © NL
The emed scientific meeting have provided us with an opportunity to learn more about
pressure distribution products, applications, and research, meet new and old friends and
experience our hospitable host sites.
We thank you for joining us in Leeds for another memorable event.
Prof. Klenerman and friends at the 1
st
emed meeting, Liverpool 1991
Q
6
novel award 2004
The novel award 2004, 5.000 euro will be presented for the best
scientific manuscript in the field of dynamic pressure distribution
analysis. Six of these abstracts were nominated for the novel
award 2004.
Their authors were requested to send a full length paper until June 15th and will present their paper
at the meeting in a 30 minutes talk. The paper must be entirely original, not published at the time of
the meeting in any journal nor submitted for publication to any journal or book. The paper must
describe a scientific study including pressure distribution measurement.
A blind review of papers was conducted by a prominent panel of experts. The novel
2004 will be presented to the winner at the banquet Sunday evening.
novel award 2004
award
Committee 2004
Professor Peter Cavanagh
Professor Benno Nigg
Professor Michael Mueller (invited as part of ESM 2002 winning team)
Professor Michael Morlock
novel 2004 © NL
Previous Winners (first authors)
Kananaskis, 2002
Katrina S. Maluf
USA
Munich, 2000
Mattheu Nurse
Canada
Calgary, 1999
Brian Davis
USA
Brisbane , 1998
Margret Hodge
Australia
Tokyo, 1997
Erez Morag
USA
Pennstate, 1996
Dieter Rosenbaum
Germany
Ulm, 1994
Michael Morlock
Germany
Vienna, 1991
Benno Nigg
Canada
Q
7
The best
ESM presentation award
Will be presented during the closing banquet on Sunday August 1st.
The award is based on the votes of 3 ESM participants.
The award winner will receive a prize of 1000 Euro.
The best
ESM poster award
Will be presented during the closing banquet on Sunday August 1st.
The award is based on the votes of 3 ESM participants.
novel 2004 © NL
The award winner will receive a prize of 1000 Euro.
Q
8
Activity day
Saturday 31th July,2004
full day mountain biking
Option 1
This will involve either- Full day long ride of around 30 – 35 km, mainly off-road hard climbs,
technical riding & good descents OR Full day medium ride of around 25- 30 km, mainly off road
shorter climbs at a steadier pace & good descents, depending on the consensus and experience of
the group.
half day mountain biking
Option 2
The biking groups will be divided according to level of ability and will involve either- Half day long
ride of 15 km – 22 km mainly off road with a good climb gaining height to get a fantastic view of
Swaledale and ride the descents. Half day shorter ride will be around 15km mainly riding along the
valley some short ups and downs.
half day walking
Option 3
We will undertake the High Level Swaledale walk. Walking
along to the riverside from Reeth to Marrick Priory, up the
Nuns Steps to Marrick and back via Fremington Edge in one
of Yorkshire’s most beautiful valleys. This is approximately
11km of moderate walking.
half day fell run
Option 4
Yorkshire Dales
The run will involve the same route as the guided walk but of course at a faster pace. Our guide, Dr
Phil Helliwell will plan the route for more/less distance after speaking to those intending to take
this option. Of course, you will need to be an experienced distance runner to take this option. If you
want to speak to our guide first then please contact him directly ([email protected]
<mailto:[email protected]> ).
half day in the town of RichmondOption 5
novel 2004 © NL
The historical market town of Richmond, with its Norman Castle, Georgian architecture, cobbled
market place, monuments and abbeys, the fast flowing river Swale, and breathtaking scenery.
A town which inspires painters and poets, past and present.
Q
9
Map of Leeds
Weetwood Hotel
novel 2004 © NL
Leeds city centre
Map of West York
Q
10
Important telephone numbers
0113 230 6000
999
0113 250 9696
0161 489 3000
0870 000 0123
0845 748 4950
0845 225 0845
44 (0) 113 343 4938
Weetwood Hall
Police/ambulance/fire
Leeds Bradford International Airport
Manchester International Airport
London Heathrow Airport
National Rail Enquiries
National Car Rentals
Non essential emergency contact number
(International- messages will be checked three times daily)
Jim Woodburn directly
0779 322 2065
* Local doctors and dentists names/numbers available from hotel reception
Cultural Events
in Leeds
During registration your hosts will have a number of brochures available covering local events and
attractions. To get you started here are 5 local attractions-
novel 2004 © NL
Royal Armouries Museum
Harewood House
Henry Moore Institute
Kirkstall Abbey
West Yorkshire Playhouse
0113 220 1916
0113 218 1010
0113 234 3158
0113 230 5492
0113 213 7700
Q
(http://www.armouries.org.uk)
(http://www.harewood.org)
(http://www.henry-moore-fdn.co.uk)
(http://www.leeds.gov.uk/kirkstallabbey)
(http://www.wyplayhouse.com)
11
Meeting overview
Thursday 29th July, 2004
Registration, buffet and wine reception, welcome address
novel workshops
Friday 30th July, 2004
Registration, Scientific Day 1
Reception at Thackray Medical Museum
Saturday 31st July, 2004
Activity day: mountain biking, walking, or trail running in the Yorkshire Dales
Sunday 1st August, 2004
novel 2004 © NL
Scientific Day 2
Banquet , Ceilidh
novelaward ceremony
Q
12
ESM 2004
Program
Thursday 29th, July, 2004
Welcome to ESM2004
18:00 - 21:00
Registration
18:30 - 21:00
Buffet and Wine Reception (Piano by Matthew Whitham)
Welcome address : Jim Woodburn (Foot pressure distribution
measurement in Leeds: work in progress in the field of rheumatology)
18:30 - 20:30
novel (GmbH) Workshops :
Workshop I Hardware
(emed recorder, pedar-x, pliance-x, sensors)
Workshop II Software
(Databases, Projects, Reports, Clinics, Diabetes software)
Friday 30th, July, 2004
Session 1
Biomechanics I
novel 2004 © NL
Chair: Dr Jim Woodburn, University of Leeds, UK
7:30 - 8:30
Registration
8:30 - 9:15
Keynote Lecture, a personal perspective on past, current and future use of
foot pressure measurement Klenerman L.
9:15 - 9:30
Using pressure distribution technology for evaluating foot function in toddlers Hallemans A, de Clercq D, Aerts P.
9:30 - 9:45
Do ankle foot orthoses improve force and pressure distribution during standing in children with hemiplegia? Hunt A, O' Reilly T, Megy M, Bronwyn T.
9:45 - 10:00
Changes in foot geometry parameters in 30 infants during the first three
years of independent walking Bosch K, Rosenbaum D.
10:00 - 10:15
Between-day reliability of repeated plantar pressure distribution
measurements in a normal population Rosenbaum D, Kersting U
10:15 - 10:45
Coffee break
Q
13
ESM 2004
Program
Friday 30th, July, 2004 cont.
Session 2
Diabetes, Multiple Sclerosis and Rheumatoid Arthritis
Chair: Dr Nick Guldemond, University Hospital Maastricht, The Netherlands
10:45 - 11:00
Synergistic effects of immuno-incompetence & plantar pressures on healing
of neuropathic pedal ulcers treated by off-loading
Sinacore DR, Mueller MJ, Hastings MK, Johnson JE
11:00 - 11:15
Risk of plantar ulceration to the surviving foot in the patients with diabetic
neuropathy following trans-tibial amputation
Kanade RV, Price PE, Harding KG, van Deursen RW
11:15 - 11:30
How are we walking in Georgia? Plantar pressure comparison
in healthy and diabetic feet
Tchitchinadze N, Pargalava N, Kotaria T, Tchitchinadze T
11:30 - 11:45
Loading pattern of the foot of patients with multiple sclerosis
Tsvetkova TL, Stoliarov ID, Abdurahmanov MA, Lebedev VV, Ilves AG
11:45 - 12:00
Plantar sensitivity and pedobarographic patterns in patients with rheumatoid
arthritis Schmiegel A, Meermeier M, Rosenbaum D
12:00 - 12:15
Reproducibility of plantar pressure measurements in patients with chronic
arthritis van der Leeden M, Dekker J, Siemonsma P, Lek-Westerhof S, Steultjens M
12:15 - 13:30
Lunch break
Session 3
novel awards Finalists I
Chair: Dr Philip Helliwell, University of Leeds, UK
13:30 - 13:55
The effect of pes cavus on foot pain and plantar pressure
Burns J, Crosbie J, Ouvrier R, Hunt A
13:55 - 14:20
Validity and reliability of plantar pressure measurements in the diabetic
neuropathic foot: a comparison of three step-protocols
Bus SA, Lange A
14:20 - 14:45
Testing the characteristics of replicas of stone age footwear discovered in
the Oetz Italian alps
Hlavacek P, Ostravska L, Gresak V, Blaha A, Vaculik J
14:45 - 15:15
Session 4
Coffee break
novel awards Finalists II
Chair: Dr Mark Cornwall, University of Northern Arizona, USA
15:15 - 15:40
Gait Evaluation during Fracture Healing in Sheep
Seebeck P, Thompson M, Parwani A, Schell H, Duda G.N
15:40 - 16:05
Forces acting in the forefoot during normal gait : a clinical application Wyss C
16:05 - 16:15
Final questions and closing remarks on the novel awards session
novel 2004 © NL
16:15 - 16:30
Chairpersons: Cornwall and Helliwell
Short break
Q
14
ESM 2004
Program
Friday 30th, July, 2004 cont.
Session 5
16:30 - 17:30
Posters
Dynamic pedography in patients with diabetic polyneuropathy after
orthopaedics surgery of the lower extremity
Vasarhelyi A, Hansen T, Fritsch C, Mittlmeier T.
Biomechanical abnormalities in patients with high risk of foot ulcer
or amputations Tsvetkova TL, Kushnir AN, Bregovsky VB, Kruchkova ZV
Remote pressure distribution measurement data analysis and data
collection: telemedicine project
Volkov AM, Seitz P, Tsvetkova TL, Fritsch C, Lebedev VV
Prevention of plantar foot traumas in weight-lifting practice
Macellari V, Varala C, Giacomozzi C
Plantar orthoses: Towards a better design to improve their
effectiveness in diabetic ulcer prevention
Giacomozzi C, D'Ambrogi E, Uccioli L, Macellari V
Changes of foot load and functional characteristics in the group of
obese children during reduction of weight Kostelnikova L, Hlavacek P
Might normalisation techniques improve the correctness of plantar pressure
measurements? Giacomozzi C, Macellari V
Foot function and morphology in different diabetic populations in New Zealand
Kersting UG, Aitken K, Gurney J, Martin S, Rosenbaum D
Posters of current work from the host institute
Multi-segment foot motion during gait: proof of concept in rheumatoid arthritis
Woodburn J, Nelson KM, Lohmann Siegel K, Kepple TM, Gerber LH
Off-loading the painful forefoot in rheumatoid arthritis is characterised by
changes to the regional velocity of the centre of pressure
Turner DE, Helliwell PS, Wakefield RJ, Emery P, Woodburn J
Debridement Of Plantar Callosities In Rheumatoid Arthritis: A Randomised
Controlled Trial Davys HJ, Turner DE, Helliwell PS, Conaghan PG, Emery P, Woodburn J
Off-the-shelf contoured orthoses demonstrate comparable mechanical properties to custom-made foot orthoses at less cost
Redmond A, Landorf K, Keenan AM, Emery P
novel 2004 © NL
18:15 ~ 21:00
Reception at Thackray Medical Museum :
a wine and buffet reception provided, including gallery tour
Q
15
ESM 2004
Program
Saturday 31th, July, 2004
Activity day
7:00 - 21:00
Getting to know each other with lots of fun outdoors
hiking, biking, communicating, and celebrating
Session 1
Foot deformities and other pathologies
Chair: Adrienne Hunt, The University of Sydney, Australia
8:30 - 9:15
Keynote Lecture
The art of using foot pressure systems as a clinical tool
Abboud R, Department of Orthopaedic & Trauma Surgery, University of Dundee, UK
9:15 - 9:30
Sagittal thickness of the plantar fascia is related to static arch shape and
regional loading of the foot in plantar fasciitis
Wearing SC, Smeathers JE, Yates B, Sullivan PM, Urry SR, Dubois P
9:30 - 9:45
How to evaluate a result in conservative flatfoot surgery with dynamic
pedobarography analysis? Toullec E
9:45 - 10:00
Detecting the presence of functional hallux limitus using dynamic foot
pressure Yizhar SKZ, Khamis S
10:00 - 10:15
Changes in the plantar pressure patterns after correction of hallux valgus
deformity with the scarf osteotomy Lorei TJ, Rosenbaum D, Klärner H, Kinast C
10:15 - 10:30
The impact of exercising on school children with valgus heel and flatfeet
Badurova J, Samsonová H
10:30 - 11:00
Session 2
Coffee break
Biomechanics II
Chair: Sharon Dixon, University of Exeter, UK
11:00 - 11:15
The problem of footwear for women in the final term of pregnancy
Cernekova M, Hlavacek P
11:15 - 11:30
Dynamic calibration and frequency response of capacitive film printed transducers Paone N, Scalise L
11:30 - 11:45
Accuracy of sensors and electronics with pedar-x insole measurements
Geuder M, Kalpen A, Seitz P
11:45 - 12:00
Biomechanical Assessment of the structure and function of Birkenstock
footbed technologies
Bray LE, Hillstrom HJ, Kim EH, Heilman BP, Song J
12:00 - 12:15
Casting methods and plantar pressure: The effects of custom made foot
orthoses on plantar pressure distribution
novel 2004 © NL
Guldemond N, Leffers P, Sanders A, Schaper N, Walenkamp G
12:15 - 13:30
Lunch break
Q
16
ESM 2004
Program
Session 3 Sports
Chair: Mario Lafortune, Nike, Beaverton, Oregon, USA
13:30 - 14:15
Keynote Lecture, Pressure distribution measurement at
the University Hospital Muenster: past,present and future uses
Rosenbaum D, University Hospital Muenster, Germany
14:15 - 14:30
Plantar pressures and foot geometry in athletes of different ethnicity
Kersting UG, Gumey J, Rosenbaum D
14:30 - 14:45
Temporal characteristic of foot rollover during barefoot jogging:
Reference data for young adults de Cock A, de Clercq D, Willems T, Vitvrouw E
14:45 - 15:00
Relationship between gait biomechanics and exercise-induced lower leg
pain: a prospective study on risk factors
Willems T, Witvrouw E, Cock AD, de Clercq D
15:00 - 15:15
Changes in plantar surface area under different loading conditions
Vicenzino B, McPoil TG, Cornwall MW
15:15 - 15:30
Application of centre of pressure to indicate rearfoot
inversion-eversion in a simulated shoe shop setting Dixon SJ
15:30 - 16:00
Coffee break
Session 4
Pressure technology applications
Chair: Scott Wearing, University of Queensland, Australia
16:00 - 16:15
Clinical proficiency of Dutch podiatrists, pedorthists and orthotists regarding
plantar pressure reduction
Guldemond N, Leffers P, Sanders A, Schaper A, Walenkamp G
16:15 - 16:30
Validity of the pedar mobile system of vertical force measurement during
a long-term period Hurkmans HLP, Bussmann JPG, Selles RW, Horemans HLD, Benda
novel 2004 © NL
E, Stam HJ, Verhaar JAN
16:30 - 16:45
Evaluation of a capacitive pressure sensor for joint contact stress
measurements Martinelli L, Rosenbaum D, D'Alessio T
16:45 - 17:00
Publicity of pressure distribution Spodrina I, Krumins M, Vetra A
17:00
Closing remarks Woodburn J, Seitz P
Q
17
USING PRESSURE DISTRIBUTION TECHNOLOGY FOR EVALUATING FOOT
FUNCTION IN TODDLERS
Ann Hallemans (1, 2), Dirk De Clercq (2), Peter Aerts (1)
1. Functional Morphology Lab, University of Antwerp, Antwerp, Belgium
2. Department of Movement Sciences, University of Ghent, Ghent, Belgium
INTRODUCTION
In bipedal gait the foot serves 3 important
functions. It acts as a shock absorber, as a stabilizer
and as a lever transmitting propulsive forces on to the
ground. The adult human foot is well adapted to these
functions, showing a complex anatomy which
combines rigidity with flexibility.
The toddler foot, however, differs greatly from
the adult human foot and is extremely flexible. The
foot skeleton is largely made up out of cartilage tissue.
The longitudinal foot arch has not yet fully developed
and is replaced by a fat pad to protect the fragile
cartilage.
In a cross-sectional study we determined the
differences between adult and infant foot function
resulting from the differences in foot anatomy
(Hallemans et al., 2003). From literature it is known
that the toddler gait pattern changes very rapidly
during the first 3 to 6 months after the onset of
walking (Bril & Ledebt, 1998). In this study we aim at
investigating the changes in foot function during this
first rapid developmental phase.
MATERIALS AND METHODS
Ten children (age 10–15 months) were followed
intensively (10 recording sessions over a 5 month
period) after the onset of independent walking. The
children walked barefoot over a pressure pad (0.4 x
0.5 m, 1.5 sensors/ cm², 250 Hz, Footscan Int.).
For analysis, we considered the course of the
centre of pressure (COP), determined roll-off patterns,
and calculated peak pressures underneath 8 areas
(med. and lat. heel, med. and lat. midfoot, med.,
central and lat. metatarsal heads and first toe). To
evaluate load bearing by the plantar surface contact
area, relative vertical impulses (RVI) were calculated
for the forefoot, midfoot and rearfoot region.
RVIrearfoot= Fzrearfoot*dt/( Fzrearfoot*dt+ Fzmidfoot*dt
+ Fzforefoot*dt)
RESULTS AND DISCUSSION
Large oscillations of the COP, suggesting
balance problems at the onset of independent walking,
decrease rapidly. After 5 months of walking the course
of the COP closely resembles the line of progression.
Three different roll-off patterns were identified
in toddlers, being toe walking (TW), flat foot contact
(FFC) and initial heel contact (IHC). At the onset of
independent walking, the majority of the children
show the TW pattern. Gradually, with increasing
walking experience, TW evolves over FFC towards
IHC. After 5 months of walking, IHC is observed in
approximately 80% of the analyzed foot falls.
1
2
3
Figure 1: In toddlers 3 different roll-off patterns
are observed: TW (1), FFC (2) and IHC (3)
Peak pressures seem to be smaller in toddlers for
the entire plantar surface area except the midfoot
region. Smaller peak pressures can be explained both
by the increased plantar surface contact area as the
soft character of the toddler foot, which allows for
impact forces to be spread over a larger area. Pressures
underneath the midfoot region are not reduced because
of the absence of the longitudinal foot arch.
At the onset of independent walking, load is
evenly distributed over the forefoot, midfoot and
rearfoot region. With increasing walking experience,
load underneath the rearfoot and midfoot region
decrease, while the importance of the forefoot in load
bearing increases. This might suggest an evolution
towards a more active push off.
REFERENCES
Bril & Ledebt, Neuroscience and Biobehavioral
reviews, 22(4):555-563, 1998.
Hallemans et al., Foot & Ankle Int., 24 (5): 444-453
CHANGES IN FOOT GEOMETRY PARAMETERS IN 30 INFANTS DURING THE
FIRST THREE YEARS OF INDEPENDENT WALKING
Kerstin Bosch, Dieter Rosenbaum
Movement Analysis Lab, Orthopaedic Department, University Hospital Muenster, Germany
INTRODUCTION
During the first years of independent walking the
child’s foot passes through changes in shape and
function. Significant changes of foot loading
characteristics within the first year of walking and the
correlation between reduction of midfoot loading
parameters and development of the longitudinal arch
were demonstrated in a previous investigation
(Bertsch, 2004).
Only little information about foot geometry in
infancy exists to differentiate physiological from
pathological foot development (Forriol, 1990).
Therefore, the aim of the present study was the
longitudinal evaluation of the development of the
infant’s foot geometry.
30 healthy infants, 16 girls and 14 boys, were
followed over the course of three years by means of
plantar pressure distribution measurements from the
onset of independent walking at a mean age of 14.4
months. The re-tests are performed every 3 months
during the first year of walking and twice a year until
the age of six. In the following study results of the first
measurement, after 1, 2 and 3 years were considered.
Five dynamic footprints for left and right feet were
collected during barefoot walking by use of the EMED
ST4 platform. To analyze the foot shape geometry
software (Novel Medical Professional 12.2.7) was
used. Forefoot width (FFW), heel width (HW),
forefoot and heel coefficient (FHC; forefoot divided
by heel), long plantar angle (LPA) and sub-arch angle
(SAA) were evaluated for each foot (Fig. 1).
Heel width and forefoot width were determined to
evaluate a static forefoot and heel coefficient (FHCs).
Differences between repeated measurements
were analyzed by using the Friedman test. The alpha
level was set at p<0.05.
For most of the evaluated parameters the results
of the pressure distribution data and the Harris mat
prints show significantly increased (FFW, HW, LPA)
and decreased values (SAA, FHC, FHCs) within the
first three years of independent walking. The increase
in dynamic and static FFW and HW shows the
expected process of growth and maturation of the foot.
The significant decrease of SAA values confirms
the previously determined reduced midfoot loading
parameters (Bertsch, 2004) which indicated the
development of the longitudinal arch already after one
year of independent walking. The geometric
parameters continued to develop during the next two
years. The significantly increased values of LPA and
the decreased values of dynamic and static FHC show
the development towards an adult foot shape.
The correlation coefficient between dynamic and
static FHC shows a low correlation which indicates
the potential difference between dynamic and static
footprints. The spatial resolution of the pressure
distribution platform in small infants’ feet could be a
limiting factor. During the process of foot growth the
impact of the spatial resolution will decline and
therefore the correlation between dynamic and static
FHC are expected to improve.
CONCLUSION
The present results show that significant changes
of foot geometry in dynamic and static measurements
appear during the first three years of independent
walking. The development of the longitudinal arch
already occurs partly during the first year of walking.
There is also a difference between dynamic and static
evaluation of foot geometry parameters.
REFERENCES
Fig.1: Calculation of forefoot (A’B’) and heel width
(AB), long plantar angle (AA’ BB’) and sub-arch
angle (LNR).
Harris mat prints were also collected during
bipedal standing to evaluate static foot geometry data.
•
•
Bertsch et al, Gait & Posture, (in print).
Forriol et al, Foot & Ankle 11: 101-104, 1990
ACKNOWLEDGMENTS
This project is supported by the Deutsche
Forschungsgemeinschaft (DFG# Ro 2146/3-1).
BETWEEN-DAY RELIABILITY OF REPEATED PLANTAR PRESSURE
DISTRIBUTION MEASUREMENTS IN A NORMAL POPULATION
Rosenbaum, Dieter (1), Kersting, Uwe (2)
1.
2.
Movement Analysis Lab, Orthopaedic Dept., University Hospital Münster, Germany
Biomechanics Lab, Dept. of Sport & Exercise Science, University of Auckland, New Zealand
INTRODUCTION
Plantar pressure measurements are an established
tool for the evaluation of foot function. In order to
achieve a satisfactory reliability, three to five repeated
trials are recommended for single sessions in clinical
applications (Hughes et al. 1991). To our knowledge,
however, it has not been evaluated how reliable the
parameters used to describe foot loading
characteristics can be obtained in separate sessions.
This information is helpful in order to estimate the
value and potential problems of repeated measurements for example in pre- vs. post-operative comparisons. Therefore, the present project investigated the
reliability of plantar pressure measurements performed
on different days in a group of normal, symptom-free
subjects.
MATERIAL & METHODS
Nine subjects (5♀, 4♂; age 26.5±8.4 years; BMI
24.0±4.5 km/m2) who were free of any neuromusculoskeletal disorders were measured on five separate days
during barefoot walking at self-selected speed. Five
trials each were collected for the left and right feet.
Measurements were repeated approximately at the
same time of day.
Data was analyzed with commercial software
(Novel Database Pro, version 11.38). For a detailed
description of foot loading 4 parameters (peak
pressure, maximum force, impulse, and contact time)
were determined in 10 areas after using the PRC-
Max. Impulse Contact
Parameter→ Peak
Pressure Force
Time
↓ Region
• med. hindfoot
0.803
0.889 0.873
0.814
• lat. hindfoot
0.817
0.911 0.894
0.833
• med. midfoot
0.788
0.776 0.738
0.788
• lat. midfoot
0.862
0.955 0.964
0.766
• med. forefoot
0.850
0.945 0.938
0.882
• central
forefoo
t
0.909
0.905 0.929
0.846
• lat. forefoot
0.689
0.708 0.767
0.802
• hallux
0.781
0.898 0.905
0.905
0.822
0.807 0.860
0.909
• 2nd toe
• lateral toes
0.687
0.805 0.930
0.924
• mean
0.801
0.860 0.880
0.847
Tab 1: Interclass Correlation Coefficients.
mask for subdividing the foot. Individual means of
five repeated trials were calculated for each foot.
These values were used to calculate the
interclass correlation coefficients (ICC) and
coefficients of variation (CoV) for all parameters since
these are accepted measures of reliability (Atkinson &
Neville 1998).
RESULTS
Moderate to high ICCs (Tab. 1) and fairly low
CoVs (Tab. 2) indicate a generally good level of
reliability that is dependent, however, on the foot
region and the chosen parameter. Areas with typically
high loading characteristics
show a higher
repeatability (e.g. central forefoot >0.9) than the less
loaded areas (e.g. medial midfoot <0.8). Contact times
showed the lowest coefficients of variation (between 2
and 11%). Regional peak pressure values appeared to
be sufficiently robust for repeated measurements with
CoVs in the predominantly loaded areas below 15%.
DISCUSSION & CONCLUSION
The present results confirm that plantar pressure
distribution measurements can be used in comparative
evaluations since the measures of repeatability for the
chosen parameters and foot regions that are typically
used in (clinical) investigations were satisfactory.
REFERENCES
Hughes et al, Clin Biomech 6:14-18, 1991.
Atkinson & Neville, Sports Med 26: 217-238, 1998.
Max. Impulse Contact
Parameter→ Peak
Pressure Force
Time
↓ Region
• med. hindfoot
7.8
5.5
8.2
6.5
• lat. hindfoot
7.0
5.8
7.5
6.3
• med. midfoot
16.9
25.7
30.9
10.6
• lat. midfoot
11.5
15.7
17.5
5.5
• med. forefoot
10.0
9.0
9.6
2.5
• central forefoot
8.1
7.8
7.0
2.2
• lat. forefoot
10.3
10.1
8.8
2.5
• hallux
14.8
11.1
13.3
6.5
15.4
17.7
16.2
6.5
• 2nd toe
• lateral toes
20.5
21.7
21.6
8.5
• mean
12.2
13.0
14.1
5.8
Tab 2: Coefficients of Variation (CoV=SD/mean in %).
SYNERGISTIC EFFECTS OF IMMUNO-INCOMPETENCE & PLANTAR PRESSURES
ON HEALING OF NEUROPATHIC PEDAL ULCERS TREATED BY OFF-LOADING.
David R. Sinacore (1), Michael J. Mueller (1), Mary K. Hastings (1),
Jeffrey E. Johnson (2)
1. Program in Physical Therapy, Washington University School of Medicine, St. Louis
MO, USA
2. Department of Orthopaedic Surgery, Washington University School of Medicine
BACKGROUND & PURPOSE
Neuropathic foot ulcers may be influenced by a
number of critical factors that may combine to
promote, delay or prevent wound healing. Our purpose
was to determine the synergistic effect of immunoincompetence and excessive peak plantar pressures
(PPP) in the region of the ulcer have on the healing
time of neuropathic foot wounds treated by pressure
off-loading.
MATERIALS & METHODS
SUBJECTS: Seventy-two subjects (53 male; 19
female; mean age = 56 + 10 yr) with diabetes mellitus
(DM), peripheral neuropathy and a neuropathic foot
ulcer were studied. Subjects had complete blood
counts (CBC) including total serum absolute
lymphocyte counts and peak plantar pressure (PPP)
during barefoot walking at their preferred walking
speed determined immediately prior to treatment with
off-loading.
PROCEDURES: Subjects were classified as
immuno-incompetence if their serum absolute
lymphocyte count was < 1700 mm3. The emed-ST
pressure platform was used to assess barefoot plantar
pressure during three walking trials at subjects’
preferred gait speed. The mean PPP in the region of
the ulcer was calculated. All subjects were treated
with maximal pressure off-loading using either total
contact casting (TCC) or a removable ankle foot
orthosis (DH Pressure Relief Walker) to heal their
neuropathic foot ulcer. All casts were applied in the
same manner by the same cast technician who was
blinded to PPP and CBC values. Healing time (defined
as number of days in the cast or AFO until complete
epithelialization of skin) was determined for each
subject.
ANALYSIS: One tailed t-tests for independent
samples were used to determine the differences in
healing time and PPP between groups of subjects
classified with different levels of lymphocyte counts.
SUMMARY DATA
In subjects whose pedal ulcers healed, the overall
average healing time was 55 + 43 days. Subjects with
pre-treatment absolute lymphocyte counts < 1700
mm3 (n=28), healed in 74.6 + 50.5 days (CI99%= 51 to
98 d) while those individuals with > 1700 mm3 (n=44)
healed in 47 + 37 days (CI99%= 29 to 61 d, p = .015).
In subjects with immuno-incompetence, the average
PPP in the region of the ulcer was 95 + 20 N/cm2
(CI99%= 85 to 140 N/cm2), while those subjects
classified as immuno-competent had an average PPP
of 75 + 29 N/cm2 (CI99%= 61 to 106 N/cm2, p = 0.003).
Four of 28 subjects (14%) with immuno-incompetence
did not heal; while in subjects classified as immunocompetent 1 subject did not heal (2.2%) and 1 subject
died (2.2%).
CONCLUSION
Subjects with immuno-incompetence (low serum
total absolute lymphocyte levels) combined with
excessive PPP in the region of their foot ulcer take
significantly longer to heal than immuno-competent
subjects using maximal pressure off-loading (either
TCC or AFO). Furthermore, immuno-incompetent
subjects may be less likely to heal using an off-loading
therapy.
RELEVANCE
We hypothesize that a reduced immunological
response to repeated high plantar pressures may act
synergistically to delay or even prevent wound
healing. Despite maximal pressure off-loading, the
synergistic combination of excessive plantar pressure
in the region of the ulcer during walking and a low
serum total lymphocyte count may delay neuropathic
foot ulcer healing as well as contribute to poor wound
outcomes.
Supported by the National Institutes of
Health; NCMRR HD36802 & NIDDK
DK59224
RISK OF PLANTAR ULCERATION TO THE SURVIVING FOOT IN THE PATIENTS
WITH DIABETIC NEUROPATHY FOLLOWING TRANS-TIBIAL AMPUTATION
Rajani V. Kanade (1), Patricia E. Price (2), Keith G. Harding (2), Robert W. van Deursen (1)
1. Research Centre for Clinical Kinaesiology, University of Wales College of Medicine, UK
2. Wound Healing Research Unit, University of Wales College of Medicine, Cardiff, UK
BACKGROUND
Following unilateral amputation in diabetes, there is a
50% incidence of amputation to the contra lateral limb
within four years (Ebskov, 1980). The aim of this
study is to investigate plantar loading of the surviving
foot.
METHODS
Twelve subjects with diabetic neuropathy and
unilateral trans-tibial amputations (TTA) were
compared with 16 matched control subjects with
diabetic neuropathy and no history of plantar
ulceration. Plantar pressure was measured with the
Pedar in-shoe system while the participants walked at
their natural pace. Gait parameters were measured by
a digital camcorder. (van Deursen, 2001). Physical
activity was recorded using the Stepwatch Activity
Monitor (Shepherd, 1999).
FINDINGS
Table 1 shows that total pressure time integral was
significantly higher in the TTA group compared to
controls. Average daily step count and gait velocity
were significantly lower. Plantar cumulative stress
was not significantly different between groups. Heel
and first-second metatarsal regions showed
significantly higher pressure-time integral values
(p=0.000 and p=0.029 respectively) but no significant
differences in peak pressure were found (p=0.525 and
p=0.491 respectively).
INTERPRETATION
Despite walking substantially slower, the trans-tibial
amputation group did not differ in plantar peak
pressure values compared to the control group but
showed increased pressure time integral values over
regions normally at risk of ulceration. However,
plantar cumulative stress was not different between
groups because of reduced activity levels in the transtibial amputation group. Adaptations in gait and
activity levels affect plantar pressure and the risk of
ulceration in the surviving foot. Rehabilitation to
increase mobility should consider implications for
plantar loading and risk of ulceration to the surviving
foot.
Figure 1: Typical 24 hour physical activity pattern
(strides recorded every minute) of a subject from the
control group (top graph: 4184 strides/24 hours) and
the TTA group (bottom graph: 2107 strides/24 hours).
Control group
Mean (SD)
Total PTI
136.1 (24.0)
Daily strides
3882 (1906)
G Vel
1.06 (0.21)
PCS
521.7 (243.9)
PP 1-2 MT
284.2 (74.6)
PTI 1-2 MT
76.1 (22.2)
* Significant (p<0.05)
TTA group
Mean (SD)
181.1 (39.4)
2317 (1113)
0.79 (0.16)
434.2 (214.2)
311.7 (114.0)
107.8 (48.0)
p
0.001*
0.014*
0.001*
0.343
0.491
0.029*
Table 1: Summary of primary results (means, standard
deviations and p-values).
PTI
Daily strides
G Vel
PCS
PP
1-2 MT
→ Pressure Time Integral (kPa.s)
→ Average Daily strides (strides/day)
→ Gait velocity (m/s)
→ Plantar Cumulative stress (MPa/day)
→ Peak Pressure (kPa)
→ First & Second Metatarsal Region
REFERENCES
Ebskov, B et al, Prosthet. Orthot. Int. 4:77-80, 1980.
Shepherd, E. F et al, J. Orthopaed Res. 17:703-708,
1999.
van Deursen RWM et al, Gait and Posture 14: 128,
2001.
HOW ARE WE WALKING IN GEORGIA. PLANTAR PRESSURE COMPARISON IN
HEALTHY AND DIABETIC FEET.
Nana Tchitchinadze (1), Nugzar Pargalava (2), Tamar Kotaria (3), Tamar Tchitchinadze (4)
1.
2.
3.
4.
"LTD Terdi", Diagnostic and Therapeutic Center, Tbilisi, Georgia.
Georgian Center of Angiology and Vascular Surgery, Tbilisi, Georgia.
INTRODUCTION
1800 subjects with various foot deformities
were examined in our center during three years. There
were – diabetic foot, hard foot, varicose, flat foot,
rheumatoid arthritis, osteoarthritis, sporting feet and
others. New measurement Emed system was used in
the study for comparison healthy (control) and
diabetic feet plantar pressure.
112 subjects, control ( W\with symptom free
feet) – and 112 diabetic feet were examined using
Novel Emed sensor platform, Germany (females
58.93%, males 41.07%; mean age 37.75 ± 17.32
years; mean weight – 78.06 ± 18.71 kg in control
group; and females 29.46%, males 70.54; mean age
57.84 ± 12.02 years; mean weight 88.13 ± 15.66 kg in
diabetes group. Maximum plantar pressure (MMP)N/cm2, maximum force (MF)-N, total contact time
(Tct), MPP contact time (MPPct), MF contact time
(MFct) – were determined through the foot (foot
divided according to the Cavanagh P.R. et al, 1987)
using three step method collection.
RESULTS
MPP N/cm2
Control
Diabetes
Heel
1st MTH
2nd MTH
Lat MTH
Great toe
42.80
±1889
52.31
±20.16
51.37
±22.23
43.14
±8.93
53.34
±23.80
36.33
±16.18
61.61
±24.51
50.20
±25.4
49.53
±23.69
48.74
±17.92
MPP frequency
Control Diabetes
4.46%
5.35%
11.60%
16.07%
46.42%
43.75%
6.25%
14.28%
31.25%
20.53%
In seconds
Control
Diabetes
Tct
1.09 ±0.36
1.69 ±0.72
MPct
0.83 ±0.32
1.19 ±0.59
MFct
0.66 ±0.28
0.97 ±0.59
MF indices were between 489-1167N in diabetic foot
and 289-1132N in control foot. It should be noted that
contrary to the control group in 26.25% lateral toes
were not visualized in diabetes (PP under lateral toes
was between 0-17Ncm2). Total contact time often was
more then three seconds in diabetes.
CONCLUSION
MPP are observed in the identical region of
the foot in control and diabetes group, but diabetes
forefoot displayed increased and longer loading than
healthy forefoot. The load on the heel and great toe
was lower and lateral toes often were not visualized in
diabetic foot. The frequency MPP increased in Lat
MTH region in the patient with diabetes. The specific
foot regions with high pressure indicate great risk for
ulcer formation in diabetics.
Our observations showed that people in Georgia walk
likewise the rest of the world, both healthy and
diabetic. At last, we think that Novel EMED system
made light revolution in the foot functional diagnostic,
treatment and prevention.
REFERENCES
1.
Cavanagh P.R et al; Foot and Ankle, 7: 262-272,
1987.
2.
Cavanagh, P.R. et al, The diabetic foot. Ed. 4
199-232. 1998).
3.
Perry J.E. et al; Journal of bone and joint surgery,
vol 77-A, 12 1819-1928, 1995.
LOADING PATTERN OF THE FOOT OF PATIENTS WITH MULTIPLE SCLEROSIS
Tatiana L. Tsvetkova (1), Igor D. Stoliarov (2), Magomed A. Abdurahmanov (2),
Viatcheslav V. Lebedev (3), Alexander G. Ilves (2)
1. novel SPb, St.-Petersburg, Russia
2. Institute of Human Brain, St.-Petersburg, Russia
3. novel, Munich, Germany
INTRODUCTION
Patients with multiple sclerosis (MS) exhibit a
reduction in velocity as the result of decrease in stride
length and cadence while step width shows an increase
over normal subjects (Walker, 1999). The observed
changes in gait of MS patients are caused by ataxia
and spasticity, both of which depend on the
progression of the disease. The aim of this study was
to determine the loading peculiarities of the foot of
patients with MS comparing with normal subjects and
in the progression of the disease.
METHODS
A total of 52 healthy volunteers (H) (20-22
years) and 71 patients (MS), 23 men and 48 women
(age 36±10 years, BMI 22±4 kg/m2), diagnosed with
progressive MS, were examined. MS patients were
divided in two groups on the base of Expanded
Disability Status Scale (EDSS): 33 patients with
EDSS<=1.5 (MS1) and 38 with EDSS>1.5 (MS2).
Clinical and foot data were collected using developed
questionnaire. Plantar pressure distributions were
performed with emed AT-25 system (novel, Munich,
Germany). Five dynamic records of each foot were
made with first step protocol. Novel database pro M
was used to collect clinical and pressure measurement
data. Foot progression angle (FPA), center of pressure
index (COPI), arch index (AI), and lateral-medial
parameters were calculated. Peak pressure (PP),
maximum force (MF), pressure-time integrals (PTI),
force-time integrals (FTI), time parameters were
calculated in novel-projects with novel automask.
Parameters were calculated for each subject and
averaged across the groups. ANOVA was used for
between-group comparison.
RESULTS
Significant changes (P<0.001) of pressure
distribution parameters were found in MS patients
comparing with healthy subjects. AI, COPI and
lateral-medial area indices (LAMAI) were decreased
(H: 0.23±0.01; MS 0.21±0.01, H: 1.27±0.11; MS
1.16±0.14 and H: 0.12±0.04; MS 0.07±0.06
correspondingly). Area between foot axis and gait line
(Ar+Al) was increased (H: 14.2±5.5 cm2; MS
17.2±8.3 cm2). Contact time was longer (H: 936±111
ms; MS 1209±344 ms), begin of contact was earlier
under all foot areas excluding the hindfoot (HF). FTI
and PTI were increased for total foot (H: 488±88 N*s;
MS 596±192 N*s and H: 272±81 kPa*s; MS 358±158
kPa*s), first and second metatarsal heads (MH), HF,
midfoot (MF), and toes. Instants of MF and PP were
earlier under the same foot areas excluding the HF.
MF and PP were decreased under MH2-4 and HF.
Comparing the patients with progression of MS
significant (P<0.001) changes were found also.
(Ar+Al) was increased (MS1: 5.8±4.4 cm2; MS
9.7±7.8 cm2). CT was longer under MH5 and toes,
begin of contact was earlier under all foot areas
excluding HF. Instant of MF was earlier for total foot
(MS1: 67±16 %ROP; MS2: 57±19 %ROP) and MH23. Instant of PP was earlier under MH2-4. MF and PP
were decreased under HF, and MH2-3. PTI was
increased under toes and was decreased under MH2-3.
The lower values of the COPI and LAMAI
reflect the unstable gait of patients with MS
comparing with healthy subjects. Loading is shifted
more medially with the progress of the disease.
Reduced lateral loading under the forefoot and
increased medial loading may be regarded as a
protective mechanism in order to avoid an imbalance
(Meyring, 1997). The first ray is the most prominent
structure to bear weight during push-off.
Low peak pressures are the result of weak motor
power, reduction of muscle strength, and insufficient
weight transfer. Therefore peak pressures are
decreased with the progress of the disease. Besides,
the spastic foot is rigid, causing limitation of
movement of the anatomical structures within the foot,
resulting in an increase of the arches of the foot.
Reduced peak pressures under the third metatarsal
head identify a higher transverse arch of the forefoot
with increase of spasticity (Meyring, 1997).
Therefore pressure distribution measurements
assess quantitatively the gait impairments in
correlation with neurological impairments.
REFERENCES
1. Meyring et al, Clinical Biomech 12: 60-65, 1997.
2. Walker et al, ASB, 1999.
PLANTAR SENSITIVITY AND PEDOBAROGRAPHIC PATTERNS IN PATIENTS
WITH RHEUMATOID ARTHRITIS
A. Schmiegel, M. Meermeier, D. Rosenbaum
Movement Analysis Lab, Orthopedic Department, University Hospital Münster, Germany
INTRODUCTION
RESULTS
The feet of patients with rheumatoid arthritis (RA)
are often affected by deformities and pain during
walking and are therefore a primary cause of limited
mobility. An early conservative treatment is strongly
recommended to protect the rheumatoid foot from
potentially destructive processes (Woodburn et al.,
2002). The aim of the treatment is to ensure
physiological loading of the feet and to prevent
overloading. However, there is a lack of knowledge
concerning the relationship between footloading,
deformities and pain and therefore of guidelines for
the treatment of pain (Waldecker, 2002).
Furthermore, compression neuropathies are reported
to be associated with RA (Chang & Paget, 1993).
However, the influence of this neurological complication on plantar sensitivity is unknown. Therefore,
the aim of this study was to examine the influence of
rheumatoid arthritis on plantar sensitivity and loading
further knowledge about the pathology and treatment
of rheumatoid feet.
RA
CG
p-value
Sens. Heel
4.56
4.17
0.010
Sens. Midfoot
4.17
3.61
0.017
Sens. MTH1
4.17
4.08
>0.05
Sens. MTH3
4.31
4.17
>0.05
Sens. MTH5
4.31
4.17
0.048
Sens. Hallux
4.24
4.17
0.014
Table 1: Results sensitivity measurements (median)
Significant Results Pedobarography:
• Lateral Hindfoot: RA show a lower AP
• Medial Midfoot: RA show a higher PP, AP, PTI and
impuls
• Lateral Midfoot: RA show a higher impulse
A v e r a g e P r e ssu r e [ k P a / m s]
T oes 345
T oe2
M T H345
RA
M T H2
PATIENTS
Control Group (CG)
• n = 12 (age 51,9 ± 9,4 years)
• Without systemic disease and walking problems
Rheumatoid arthritis Patients (RA)
• n = 26 (age 56,6 ± 10,2 years )
• No history of foot surgery
• Bilateral walking pain in feet
• No further neurological disease
METHODS
Pedobarography
• Platform: EMED ST4
• 5 steps with the right (& left) foot were recorded
• Subivision of the foot in 10 regions
• Detection of Peak Pressure (PP), Average Pressure
(AP), Pressure–Time Integral (PTI), Impulse
Patient Scores
• Health assessment questionnaire (HAQ)
• Foot Function Index (FFI)
• Rheumatoid Arthritis Disease Activity Index
(RADAI)
• Walking Pain (Verbal Rating Scale)
Sensitivity Assessment
• Semmes-Weinstein Mono Filaments (right foot)
• 5 areas: heel, midfoot, Metatarsal head 1/3/5, hallux
• Modified 4-2-1 step algorithmDyck, 1999).
CG
MTH 1
M edi al mi df oot
M edi al hi ndf oot
Lat er al mi df oot
Lat er al hi ndf oot
Hal l ux
0
0. 05
0. 1
0. 15
0. 2
0. 25
0. 3
0. 35
0. 4
Graph 1: Pedobarographic results AP
DISCUSSION
The sensitivity assessment demonstrates a decrease
in the plantar sensitivity in all regions of the foot. A
standard interrelation between plantar sensitivity and
foot loading could not be found. Therefore, decreased
sensitivity may only have a lower effect on gait
modification in RA.
REFERENCES
• Woodburn et al., J Rheumatol 29: 1377-83, 2002.
• Waldecker, JFoot Ankle Surg 41: 300-8, 2002.
• Chang & Paget, Rheumatic disease clinics of north
america 19: 955-73, 1993.
• Dyck, P.J, Neurology 43: 1508-12, 1999.
Financial support of the BMWiA (ProInno) is
gratefully acknowledged.
REPRODUCIBILITY OF PLANTAR PRESSURE MEASUREMENTS IN PATIENTS
WITH CHRONIC ARTHRITIS
Marike van der Leeden (1), Jos Dekker (1), Petra Siemonsma (1), Sandy Lek-Westerhof
(1), Martijn Steultjens (2)
1. Jan van Breemen Instituut, Centre for Rheumatology and Rehabilitation, Amsterdam, The
Netherlands
2. VU Medical Centre, Amsterdam, The Netherlands
ABSTRACT
In patients with foot complaints due to
chronic arthritis the measurement of plantar pressure
is considered to be promising. It may provide
clinicians and researchers with information linking
foot complaints and dynamic pressure distribution
under the foot. However, the first step towards clinical
application and research on foot problems in chronic
arthritis patients is knowledge of the reproducibility of
plantar measurements. The reproducibility of plantar
pressure measurements has been studied in healthy
subjects. However, the differences in gait and pressure
distribution between pathological and nonpathological feet may cause problems transferring
these results to subjects with foot problems secondary
to chronic arthritis.
The reproducibility of plantar pressure measurements
in patients with chronic arthritis was compared for
three different testing methods: a one-step, two-step
and three-step protocol for data collection. In addition,
the number of measurements needed for a consistent
average measurement result was estimated for the
protocol that was found to be most reproducible. A
sample of 20 arthritis patients with foot complaints
secondary to chronic arthritis participated in the study.
Each patient was tested for two of the three testing
protocols, using a pressure platform system (Emed,
Novel). The parameters contact time and maximal
peak pressure were used to assess reproducibility.
The results of this study indicated that the one-step,
two-step and three-step protocol of collecting plantar
pressure measurements in chronic arthritis patients
were all consistent (see table 1). However, the use of
the two-step protocol was recommended. The one-step
protocol produced a longer stance phase and therefore
did not resemble normal walking. When comparing
the two- and three step protocol, the two-step protocol
was recommended because this protocol was less time
consuming and less strenuous for patients with painful
feet. Using the two-step protocol three measurements
were sufficient for a consistent average measurement
result (Leeden van der, 2004).
In order to obtain high reproducibility the instructions
and familiarisation of the patient with the
measurements must be clear and follow a protocol.
This study contributes to the decrease of measurement
errors in plantar pressure measurements. However,
more research to improve the standardisation of
measurement protocols in arthritis patients is needed.
Inter tester reproducibility is a further and important
issue in reproducibility studies and is defined as the
degree to which different testers can achieve the same
results on the same subjects. For the purpose of
clinical reasoning, also more research needs to be
done on the relationship between foot complaints and
pressure
distribution
in
arthritis
patients.
Investigations of both inter tester reproducibility and
the relationship between foot complaints and pressure
distribution in arthritis patients are in preparation by
the same group of researchers.
TABLE
CT
PP
1-step
0.91a
0.72b
Right foot
2-step
0.82a
0.81a
3-step
0.88a
0.76 b
1-step
0.86a
0.91a
Left foot
2-step
0.86a
0.90a
3-step
0.91a
0.83a
Table 1: Intraclass Correlation Coefficients of Both Right
and Left Feet for One-step, Two-step and Three-step
Protocol
CT, Contact Time
PP, Peak Pressure
a
Good reproducibility (>0.80)
b
Reasonable reproducibility (>0.60)
REFERENCE
Leeden van der et al., Foot & Ankle Int,
accepted 2004.
THE EFFECT OF PES CAVUS ON FOOT PAIN AND PLANTAR PRESSURE
Joshua Burns1, Jack Crosbie1, Robert Ouvrier2, Adrienne Hunt1
1. School of Physiotherapy, The University of Sydney, NSW, Australia.
2. Institute for Neuromuscular Research, The Children’s Hospital at Westmead, NSW,
Australia.
INTRODUCTION
Patients with a pes cavus foot posture commonly
present with pain, and are a challenging clinical
situation for the health professional. Elevated plantar
pressure has been most regularly highlighted as the
cause of foot and ankle pain in these patients
(Metaxiotis, 2000; Sneyers, 1995). The purpose of this
study was to examine the effect of pes cavus on foot
pain and dynamic plantar pressure, and to explore the
relationship between pressure loading and foot pain.
METHODS
Seventy volunteers (41 female, 29 male) were
recruited for this study including 30 subjects with an
idiopathic pes cavus, 10 subjects
with a neurological pes cavus and
30 subjects with a normal foot
type, defined by the Foot Posture
Index (Redmond, 2001).
Prevalence and location of foot
pain were recorded and barefoot
plantar pressures were measured
using the EMED-SF platform for
3 steps of each foot using the
midgait protocol at a self selected
speed. Pressure-time integral
(PTI), mean pressure and contact
time were calculated for the total
foot, rearfoot, midfoot and
forefoot masks of each step
(Figure 1).
Figure1.Mask divisions.
RESULTS
Of the 70 subjects studied, 31(44%) reported some
type of current musculoskeletal foot pain. The pes
cavus foot type, of either idiopathic or neurological
aetiology, was associated with a significantly higher
frequency of foot pain (χ2 = 9.341, p=0.009).
Significant increase in PTI was recorded for both the
idiopathic and neurological pes cavus groups
compared to the normal foot type group (Table 1).
Significant elevation in mean pressure was recorded
for the idiopathic pes cavus group compared to the
neurological pes cavus and normal group (p<0.05).
Significant increase in contact time was recorded for
the neurological pes cavus group compared to the
idiopathic pes cavus and normal group (p<0.01).
There was a significant correlation between PTI and
symptomatic subjects (r=0.415, p=0.000). Coefficient
of determination (r2) was 0.1722, indicating that 17%
of the variability in occurrence of foot pain could be
attributed to differences in plantar pressure loading.
Our results also showed a significant difference
between the mean PTI values in subjects reporting
foot pain as compared to asymptomatic subjects (z= 3.447, p=0.001).
DISCUSSION AND CONCLUSIONS
The results of this investigation indicate individuals
with a pes cavus, of either idiopathic or neurological
aetiology, suffer high levels of foot pain. They
experience elevated plantar pressure loading (PTI)
compared to normal, which can be attributed to either
high pressures of short duration (idiopathic) or low
pressures of long duration (neurological). The PTI is a
clinically important assessment method and may be a
useful outcome measure in the treatment of painful pes
cavus.
Foot
region
Total
Rearfoot
Midfoot
Forefoot
Normal
foot type
23.8 (5.1)
8.5 (1.9)
2.3 (1.0)
18.4 (5.5)
Idiopathic
pes cavus
29.8 (8.3)*
10.7 (2.4)*
2.2 (1.8)
23.7 (8.5)*
Neurologic
pes cavus
29.9 (6.6)*
12.7 (5.5)*
3.4 (2.6)
25.0 (7.9)*
Table 1: The plantar pressure loading (N.s/cm2)
characteristics between foot types. *Indicates
significant difference compared to normal (p<0.05).
REFERENCES
Metaxiotis D et al, Foot Ankle Int 21(11):935-947,
2000.
Sneyers C.J et al, Foot Ankle Int 16(10):624-32, 1995.
Redmond A et al, J Orth Sports Phy Ther 31(3):160,
2001.
VALIDITY AND RELIABILITY OF PLANTAR PRESSURE MEASUREMENTS IN THE
DIABETIC NEUROPATHIC FOOT: A COMPARISON OF THREE STEP-PROTOCOLS
Sicco A. Bus (1), Anthony de Lange (2)
1. Department of Internal Medicine, University of Amsterdam, Amsterdam, The Netherlands
2. Fontys University for Professional Education, School for Podiatry, Eindhoven, The
Netherlands
INTRODUCTION
Barefoot plantar pressure measurements are
routinely used in the risk evaluation for plantar
ulceration in the diabetic neuropathic foot. For this
assessment, different step-protocols (1-,2-, or 3-step,
midgait) have been used and a different number of
repeated trials have been collected. The choice for one
of these methods is often not motivated. Although it is
imperative that valid and reliable pressure data is
obtained, these different protocols and methods have
not been compared in neuropathic diabetic patients.
Therefore, the aim was to determine in these patients
the validity and reliability of a 1-step, 2-step, and 3step-protocol
for
barefoot
plantar
pressure
measurement.
was generally shorter with fewer steps made before
platform contact, but only the difference between the
1-step and 3-step protocols in the heel was significant
(P<0.05). ICCs for 10 trials were high (>0.87) and
comparable between step-protocols (Figure 1).
Reliable estimates (ICC >0.85) of peak pressure
were achieved with collecting 3 trials in the 2-step
protocol, and 4 trials in the other two protocols; for
reliable pressure-time integral data 7 (1-step), 4 (2step) and 5 trials (3-step) needed to be collected.
METHODS
Barefoot plantar pressures were measured in 14
diabetic neuropathic patients with severe loss of
protective sensation (vibration perception threshold >
35 Volts) who repeatedly made one, two or three steps
before contacting an EMED-NT pressure platform
(Novel, Munich, Germany). Ten trials were collected
per step-protocol. The 3-step protocol was regarded as
reference condition and comparable to midgait since 3
steps are needed to achieve steady state gait (Mann et
al, 1979). Peak pressure, pressure-time integral and
contact time were calculated for each of 6 anatomical
foot regions. Intraclass correlation coefficients (ICC)
determined the reliability of each protocol.
Figure 1: ICC for peak pressure as a function of the
number of trials for each region in the 1-step (P1), 2step (P2), and 3-step (P3) protocols.
CONCLUSIONS
1-step
2-step
3-step
Heel
402 (126)
398 (119)
394 (113)
Midfoot
130 (74)
126 (59)
111 (46)
MTH1
415 (186)
406 (186)
423 (227)
MTH 2-5
559 (174)
568 (171)
561 (164)
Hallux
418 (268)
430 (250)
437 (278)
Toes 2-5
162 (84)
164 (76)
169 (81)
Table 1: Peak pressures (mean (SD) of 10 trials)
expressed in kPa for each region and step-protocol.
The data show that barefoot plantar pressure
in neuropathic feet can be assessed in a reproducible
manner with any of the step-protocols used. The ICCs
found are comparable to those found in non-diabetic
feet measured with a similar system (Novel EMED)
(McPoil et al, 1999). The 1-step and 2-step protocols
are valid methods for pressure assessment as the lack
of any significant difference with the reference
condition (3-step protocol) shows. Because the 2-step
protocol requires the least amount of trials for reliable
pressure data, the use of this protocol is recommended
when measuring barefoot pressure data in neuropathic
feet at high risk for plantar ulceration.
RESULTS
REFERENCES
No significant differences in regional peak
pressure (Table 1) and pressure-time integral were
present between the three step-protocols. Contact time
McPoil et al, J Am Podiatr Med Assoc 89:495-501,
1999.
Mann et al, J Bone Joint Surg Am 61:232-239, 1979.
TESTING THE CHARACTERISTICS OF REPLICAS OF STONE AGE FOOTWEAR
DISCOVERED IN THE OETZ ITALIAN ALPS.
Petr Hlavacek, Lenka Ostravska, Vaclav Gresak, Antonin Blaha, Jaromir Vaculík†
Faculty of Technology, Tomas Bata University, Zlin, The Czech Republic
In 1991, in the Ōtzital Alps, the frozen
mummified body of a man who, according to analysis,
died a violent death over 5300 years ago. The
construction and use of materials fundamentally
changed opinions about the beginnings of human
footwear.
The remains of the footwear were studied very
intensively and answers were sought for the questions:
which animal skins were used for shoes; what type of
tanning was used; how was footwear proportionality
resolved; how was it completed and what degree of
foot protection did it provide.
INTRODUCTORY STUDY
For establishing the dimensional proportionality
of the footwear, measurement of the foot of the
mummy was important, as was the careful
documentation of segments of the preserved shoes.
The use of 3D analyses succeeded in determining
orientationally the original dimensions of the footwear
and subsequently the thickness of the hay filling
between the foot and the footwear.
The tanning technology was relatively difficult
to establish. Microscopic studies and assessments of
temperature of contraction confirmed that the skin was
tanned with fat. But which fats were used for tanning
was not determined. It is possible to use only fats with
unsaturated double bonds for tanning and it is not
clear which oil or fats could have been used in the
later Stone Age. On the basis of experience with
primitive tribes and a series of attempts, the use of a
mix of animal livers and brain has emerged. Using this
procedure, it was possible to tan bear and goat skins.
PRODUCTION OF THE REPLICA
According to a dimensional analysis, initial
footwear replicas were completed in a 1:1 ratio. The
skins were cut using a claw, openings completed using
a bone needle. From the bast, initially while moist, a
double-thickness twine was completed and from this
the bearing netting was processed. Production of one
pair after acquiring experience from the prepared raw
materials took about 4 hours.
ARCHAEOLOGICAL EXPERIMENT
The atypical construction of the footwear invokes for
professionals doubts about the utility and protective
characteristics. Therefore, five pairs of shoes were
completed to fit for a practical test wearing of the
shoes in the terrain of the Ōtzital Alps. Four
volunteers ascended in the replicas from the village of
Vent to the site of the discovery of Ōtzi. The length of
the trek was about 20 km to the summit and 20 km
back, exceeding an elevation difference of approx.
1500 m. Temperatures from – 10º to +10º C. The
footwear was worn without socks. Over the course of
the experiment, temperatures of the foot and the inside
of the shoes were measured. The temperature of the
foot never dropped below 25º C. Chilblains, calluses
or blisters did not occur on any of the volunteers. The
footwear had anti-skid characteristics comparable with
modern peg treatment on a rubber sole.
LABORATORY TESTS
After the completion of the archaeological
experiment, the replicas were tested under laboratory
conditions according to known methods and standards.
Thermal insulation characteristics were measured
(under various moisture values). The measured values
of the hay layers were better than the thermal
insulation characteristics of winter shoes. The friction
co-efficient and anti-skid characteristics of the sole
were verified, which at the same time confirmed an
above average value.
The final part of the experiment was
concentrated on the distribution of local pressures
between the foot and the shoes using an PEDAR
Mobil instrument. Also measured on five athletes,
teachers and students were sports shoes, hiking boots
and walking shoes in addition to the replicas of
footwear from the Stone Age. Distribution of pressure
between the foot and the shoes were evaluated and
mutually compared. Also in this case, the replicas
were comparable or better than current footwear.
CONCLUSIONS
Laboratory test and the results of the
archaeological experiment have confirmed that
footwear used more than 5300 years ago are
capable of perfectly protecting the foot during
movement in high-alpine conditions and in the
majority of measurable parameters, it is even
better than current hiking shoes.
GAIT EVALUATION DURING FRACTURE HEALING IN SHEEP
Petra Seebeck, Mark Thompson, Abdul Parwani, Hanna Schell, Georg N. Duda
Center for Musculoskeletal Surgery, Charité - University Medicine Berlin, Germany
OBJECTIVE
The postoperative loading of a fractured limb
influences the course of fracture healing. Whilst both
total rest and early full weight bearing are considered
to be detrimental, controlled mechanical stimulus may
promote fracture healing (Buckwalter, 1999).
Additionally, early mechanical conditions at the
fracture site have a strong effect on the later healing
course (Klein, 2003).
The aim of this study was to evaluate possible
correlations between fracture stiffness, callus
composition and limb loading during the course of
fracture healing. In addition, two different fixation
stiffnesses were compared for their influence on limb
loading and fracture healing.
reduced to a 3 dB loss at 10 weeks. The contralateral
limb showed a corresponding 14 dB increase in this
frequency range at 4 weeks, retaining a 6 dB increase
at 9 weeks.
CONCLUSIONS
The initial mechanical situation at the fracture
site was obviously influenced by limb loading.
Thereafter, limb loading was strongly related to the
course of callus mineralisation. Therefore, this study
was not able to define a general causal effect. Reduced
levels of 5-10 Hz loading in the healing limb persisted
to 9 weeks post-operatively. Gait analysis is a valuable
tool for monitoring the course of fracture healing as it
provides a sensitive indicator for functional recovery.
CLINICAL RELEVANCE
METHODS
Standardised 3 mm diaphyseal bone defects were
created in the right tibia of 16 female sheep and
stabilised with either a rigid monolateral external
fixator (REF) or a more flexible variant (FEF) Gait
parameters were measured pre- and weekly postoperatively up to 9 weeks using a pressure sensitive
platform (emed ST-4, Novel, Munich). The
interfragmentary movements (IFM) at the fracture site
were measured simultaneously. Frequency profiles
were calculated for the ground reaction forces. The
tibiae were tested biomechanically after sacrifice and
callus sections were analysed histomorphometrically.
RESULTS
The gait analysis revealed an unloading of the
operated hindlimb in combination with an overloading
of the contralateral hindlimb (Fig. 1). Callus
mineralisation and stiffness increased during healing
thus causing a decrease of IFM (Fig. 2) whilst limb
loading increased in parallel. No differences in limb
loading were observed between the two groups. The
initial axial torsional movement (ATM) at the fracture
site showed a significant correlation with initial
loading (τ = 0.358, p = 0.01). Larger IFM resulted in a
slower fracture healing rate as documented by
histological and biomechanical results. The frequency
analysis showed a 14 dB loss of power at frequencies
(5 – 10 Hz) considered to be important for bone
mechano-transduction (Warden and Turner, 2004) in
the operated limb at 4 weeks postoperatively. This
Limb loading directly reflects the recovery of
stiffness at the fracture site. Different fixation
stiffnesses did not lead to different loading scenarios
but to different healing rates. Changes in limb loading
that may affect bone healing persist to 9 weeks postoperatively.
ground reaction force Fmax [%]
Limb loading and interfragmentary movements at
the fracture site were measured during the course of
fracture healing and correlated with clinical and
histological findings in an ovine fracture model.
160
140
120
100
80
operated limb
contralateral limb
60
0
10
20
30
40
50
60
70
days post surgery
Fig. 1: Partial unloading of the operated limb after
surgery and overloading of the contralateral limb*
1,8
1,6
axial torsional movement [°]
STUDY DESIGN
REF
FEF
1,4
1,2
1,0
0,8
0,6
0,4
0,2
0,0
0
10
20
30
40
days post surgery
50
60
70
Fig. 2: ATM decreased during fracture healing*
REFERENCES
Buckwalter et al., J Am Acad Orthop Surg 7: 291-299,
1999; Klein et al., J Orthop Res 21(4):662-9, 2003;
Warden and Turner Bone 34:261-70, 2004.
* the data are given as medians, bars are indicating the 1st and
3rd quartile respectively
Forces acting in the forefoot during normal gait- a clinical application
Christian Wyss
Departement of Orthopaedic Surgery, Kantonsspital Aarau AG, Aarau (Switzerland)
BACKGROUND AND OBJECTIVE
The paper of Hilaire Jacob (HAC Jacob, 2001) clearly
showed that the forces measured directly at the foot
don't correspond to the forces really resulting at the
foot. The “internal” forces like muscle forces change
both the direction as well as the amount of the
resultant forces. The goal of this work was the
development of a mathematical forefoot model to
determine the operation technique using individual
gait analysis data.
MATERIAL AND METHODS
The static model of Jacob was developed into a
dynamic one. The model is now applicable to the first
until fifth ray and for the whole stance phase while the
extensor muscles are inactive. To get the input data for
this model we use an EMED dynamic pressure
measurement platform, a Vicon 250 3D-movement
analysis system with 4 cameras and a Noraxon 2000
electromyography system.
With standing x-rays (same position as doing the
offset/zeroing for the movement analysis) of each
patient, we get the anthropometric data for the
mathematical forefoot model (e.g. length of phalanges,
metatarsals, angle between metatarsals and floor).
Dynamic pressure measurement: we use the second
step method i.e. the probationer meets the platform at
the 2. Step. Forces are calculated in 12 areas of the
foot to get the input (external) forces for our model.
Normally, we determine the median from 5 steps after
a time normalization (stance phase = 100%). The
forces are declared in percent of the bodyweight.
3D movement analysis: we use a segmental reference
system with 9 markers. 3 at the lower leg, 3 at the
hindfoot and 3 at the forefoot. We chose to adopt a
similar method as proposed by Chao (1980) and
Grood and Suntay (1983) for defining our anatomical
joint angles.
The electromyography is done with surface electrodes.
We determine the electrical activity of the posterior,
lateral and anterior muscle group of the lower leg.
Time normalization, rectification and a RMS filter is
used. We determine the average electrical activity over
5 steps. As an assumption we consider a muscle as
active when its activity during gait is higher as this
average. In this case we calculate the muscle forces
with the equation of motion, which we get from our
foot model (free body diagram).
In order to get norm values, we examined 500 healthy
probationers with dynamic pressure measurement, 100
healthy probationers with 3D movement anaylysis,
EMG and standing x-rays.
RESULTS AND CONCLUSION
With this method we can preoperatively simulate on a
computer the effect of forefoot surgery. For example:
in a additional study with 205 patients with
metatarsalgia we saw that there are some patients with
increased resultant forces at the second metatarsal
head compared to the norm values. Using gait analysis
data as input data in our model, a computer simulation
showed us that a decrease of the direct forces at the
second metatarsal reduces not in every case the
resultant force. In some cases it was more successfully
to reduce the muscle forces, in some cases it was
better to shorten the second metatarsal, in other cases a
basal resection with shortening of the phalanges
showed a good reduction of the resultant force.
With this method we can evaluate the best possible
operation technique purely mathematically but
individually on basics of gait analysis data and x-ray.
FUTURE PROSPECTS
As an additional tool to the clinical examination we
use this forefoot model also to choose the operation
technique for hallux valgus surgery. Interestingly we
find often postoperatively better results of some
parameters (e.g. power curve and torque moment at
the metatarsophalangeal joint) as calculated before the
operation. Further investigations in this topic are
necessary to integrate this interesting increase of some
parameters which we cannot determine with our
calculations.
REFERENCES
Chao E.Y., Journal of biomechanics 13:989-1006,
1980
Grood E.S et al. Journal of Biomechanical
Engineering 105, 136-144, 1983
Jacob HAC, Clinical Biomechanics 16:783-792, 2001
DYNAMIC PEDOGRAPHY IN PATIENTS WITH DIABETIC POLYNEUROPATHY
AFTER ORTHOPEDIC SURGERY OF THE LOWER EXTREMITY
Vasarhelyi A. (1), Hansen T. (1), Fritsch C. (2), Mittlmeier T. (1)
1. Klinik und Poliklinik für Chirurgie, Abt. für Unfall- und Wiederherstellungschirurgie,
Universität Rostock, Deutschland
2. novel gmbh, Ismaninger Str. 51, 81675 München, Deutschland
INTRODUCTION
Diabetic polyneuropathy (DPN) is well known to
induce pathologic plantar roll motion following high
peak plantar pressure (PPP) as an important predictor
of diabetic foot ulceration.
Many patients with DPN, regarding their
advanced age, require orthopedic procedures due to
arthrosis of the hip and knee joint or fractures of the
lower extremity.
The aim of this pedographic study was to
compare control patients with DPN without foot
ulceration with patients after orthopedic surgery of the
lower extremity and DPN in history in order to define
specific postoperative changes of plantar pressure
distribution and PPP.
PATIENTS AND METHODS
6 patients and 15 control patients
were
examined on emed platform and with pedar mobile
system for analysis of dynamic sole pressure
distributions barefoot and shoed.
All control patients had clinically assured DPN
without any foot ulceration in history. 6 patients with
DPN, who had an orthopedic procedure of the lower
extremity (hip and knee replacement, ankle
osteosynthesis), were selected.
Measurements of three standardized cycles of
each method were performed after early postoperative
mobilisation under instruction of a physical therapist,
1 month and 4 months postoperatively.
Data and statistical analysis was based on the
parameters force-time integral, pressure-time integral
and the averaged maximum pressure.
RESULTS
All control patients showed a typical neuropathic
roll-over process in foot flat position at ground contact
with immediate forefoot loading on platform
measurements. 14 of 15 control patients had
symmetrical
plantar
pressure
distribution.
Asymmetrical PPP of the lateral midfoot were found
in one control patient.
During in-shoe measurements 7 control patients
had comparable pressure patterns to barefoot results
on platform. PPP of 2 control patients were reduced in
the heel and lateral midfoot region, while 6 control
patients showed elevated PPP in lateral mid- and
forefoot regions.
The plantar pressure patterns of the 6 operated
patients on platform were also typically neuropathic
but showed a significant reduction of pressure loading
and impulse (force-time integral) of all foot regions of
the operated limbs after early postoperative
mobilisation.
During follow-up investigations 1 and 4 months
postoperative we found a consequent increase of
pressure loading and impulse mainly in the forefoot,
lateral midfoot and also hallux regions with
approximation to the plantar pressure pattern of the
individual non-operated side.
PPP of dynamic in sole measurements of the
operated foot were similar to platform results in 2
cases, while 4 patients had increased PPP in heel (1),
midfoot (2), forefoot (3) and hallux region (2).
CONCLUSIONS
Plantar pressure distribution measurements of
patients with DPN after orthopedic surgery of the
lower extremity showed a significant reduction of PPP
in the early postoperative phase and a recurrence of a
bisymmetrical neuropathic plantar pressure pattern
after rehabilitation. Standard footwear may increase
the risk of foot ulceration due to elevated PPP in
forefoot regions postoperatively compared to barefoot
gait.
REFERENCES
Hayes A, Seitz P. The average pressure
distribution of the diabetic foot: can it be used as a
clinical diagnostic aid? Clin Biomech 12(3): S3-S4,
1997
Luger E, Nissan M, Karpf A, Steinberg E, Dekel
S. Dynamic pressures on the dynamic foot. Foot Ankle
Int 22(9): 715-719, 2001
Mueller MJ, Hastings M, Commean PK, Smith
KE, Pilgram TK, Robertson D, Johnson J. Forefoot
structural predictors of plantar pressures during
walking in people with diabetes and peripheral
neuropathy. J Biomech 36(7): 1009-1017, 2003
BIOMECHANICAL ABNORMALITIES IN PATIENTS WITH HIGH RISK OF
FOOT ULCER OR AMPUTATIONS
Tatiana L. Tsvetkova (1), Alexandra N. Kushnir (2), Vadim B. Bregovsky (3), Zinaida V.
Kruchkova (2)
2. Endocrinological Center, St.-Petersburg, Russia
3. Diabetological Center, St.-Petersburg, Russia
INTRODUCTION
Clinical and biomechanical risk factors of plantar
ulcer development and amputations in patients with
diabetes are well known. Widely used protocols of
risk identification in population based screening are
traditionally based on clinical criteria and include
history of ulcer and amputations, monofilament
testing, foot pulses palpation, presence of foot
deformities. Abnormal biomechanics is mainly a result
of peripheral neuropathy, foot deformities and limited
joint mobility. Therefore biomechanical parameters
may be used for quantitative assessment of risk
degree. The aim of this study was to investigate
parameters of plantar pressure distribution at the
patients with different risk of ulcer or amputations.
METHODS
163 diabetic patients were examined using
specially developed questionnaire. History of low
extremity amputations (LEA) and/or plantar ulcers
(PU), ability to feel 10g monofilament, evidence of
peripheral vascular disease (PVD), and deformities
were the base to assess the degree of risk to develop
ulcer. Low (no risk factors), medium (presence of
neuropathy, absence of PVD and deformities), high
(presence of neuropathy and foot deformities or
evidence of PVD), and extremely high (history of
LEA or/and PU) were used for risk stratification.
High and extremely high risk of ulcer
development was found at 61 patients (37.4%). 55
patients (33 women and 22 men), age (64.5±10.3)
years and BMI (27.4±4.9) kg/m2 gave their consent to
continue the examination.
First, patients were divided in two groups: 41
patients with high risk (HR) and 14 with extremely
high risk (EHR). Then patients with high risk were
divided in three groups: 10 patients with neuropathy
and deformities, but absence of PVD (G1), 11 with
neuropathy and evidence of PVD (G2), 20 without
neuropathy but evidence of PVD (G3). At last patients
with evidence of PVD only were divided in two
groups: 5 patients without deformities (G31) and 15
with deformities (G32).
Plantar pressure distribution measurements were
performed with emed AT-2 system (novel, Germany)
using first step protocol with five dynamic records of
each foot. novel clinics database was used to collect
data. Peak pressure (PP), maximum force (MF),
pressure-time integrals (PTI) and force-time integrals
(FTI), time parameters were calculated in novelprojects with novel automask. ANOVA was used for
comparison between groups.
Comparing the patients with high and extremely
high risk, contact time was significantly longer, MF
and FTI were increased for patients without history of
LEA or/and PU (HR: 1415±315 ms; EHR: 1325±216
ms; P<0.003; HR: 838±130 N; EHR: 780±293 N;
P<0.001; HR: 790±236 N*s; EHR: 703±194 N*s;
P<0.001).
Contact time was longer and PP was decreased
for patients without neuropathy but evidence of PVD
(G2: 1336±333 ms; G3: 1451±308 ms; P<0.003; G1:
773±299 kPa; G2: 755±265 kPa; G3: 644±269 kPa;
P<0,001). MF and PTI were increased for patients
with neuropathy and absence of PVD (G1: 876±145
N; G2: 819±105 N; P<0.003; G1: 522±187 kPa*s; G2:
448±145 kPa*s; G3: 644±269 kPa*s; P<0.003).
Instant of peak pressure was later for patients with
neuropathy and evidence of PVD (G1: 73±13 %ROP;
G2: 80±10 %ROP; G3: 75±15 %ROP; P<0,004).
Comparing the patients without neuropathy but
evidence of PVD, with and without deformities,
contact time was longer, FTI were increased and PP
were decreased in case of absence deformities (G31:
1567±392 ms; G32: 1406±254 ms; P<0.001; G31:
868±265 N*s; G32: 772±196 N*s; P<0.005; G31:
522±182 kPa; G32: 693±283 kPa; P<0.001).
No significant differences were found for instant
of MF (%ROP).
Regional analysis gave the detailed picture of
foot areas loading in the groups of high and extremely
high risk of ulcer development or amputations.
Groups of patients with high risk of ulcers
included both patients with neuropathy and
deformities, and evidence of PVD. Pressure
distribution parameters were increased in the group of
patients with peripheral neuropathy and deformities.
REMOTE PRESSURE DISTRIBUTION MEASUREMENT DATA ANALYSIS AND
DATA COLLECTION: TELEMEDICINE PROJECT
Alexander M. Volkov (1), Tatiana L. Tsvetkova (1), Viatcheslav V. Lebedev (2), Christoph
Fritsch (2), Peter M. Seitz (2)
2. novel, Munich, Germany
INTRODUCTION
Telemedicine (TM) is widely used during the
last 30 years in different fields of medicine in data
analysis and data collection. It is a combination of
information technologies, telecommunications and
medicine.
TM systems can handle several tasks:
1. Remote data analysis with report creation on
a server and transfer of the report to a
customer
2. Collection of customer data to a server
database
3. Expert system (creation of knowledgebase).
Because data analysis with the help of scientific
software is not affordable for all users a telemedicine
system was developed to create scientific reports
directly on the server and to transfer the reports via
Internet.
METHODS
Communication in TM system is implemented
on the basis of Hypertext Transfer Protocol (HTTP),
since it is widely used and user-friendly.
There are two modes of communication with the
computer server. First mode: being connected to the
internet, the customer directs his browser to the server
homepage, logs into the system, uploads the patient
measurement data, adds clinical data and requests a
special report type from the server. Multiple file
selection for data upload in browsers is not available
in this mode, even for java applets (Java Virtual
Machine has no access to user’s file system). Second
mode resolves this issue and provides direct
communication with novel database in a thin-client
program, which the customer has to download and to
run on his computer. This native Win32 application
works as a “smart” browser that allows a selection of
multiple data files from the disk or from the novel
database via Dynamic Data Exchange (DDE) and uses
the same Hypertext (HTML) interface to the server as
standard browsers.
The server part for the remote PDM data analysis
consists of a Web server, a Common Gateway
Interface (CGI) scripts for handling user requests, with
secure login function and billing system. CGI scripts
can use several techniques to connect to data analysis
software: DDE data transfer, Component Object
Model (COM) inter-process communication, loading
of Dynamic Linked Libraries (DLLs).
RESULTS
Remote pressure distribution measurement
(PDM) data analysis is implemented in a client-server
way, which involves a novel database, a data
uploading program and a server-side script. The server
software automatically creates the selected report and
all report files are placed on the novel website where
they are directly accessible by the customer. Based on
the uploaded PDM data files, the calculated
parameters are automatically returned to the
customer’s database.
The collection of customer data is implemented
in two ways: a) as automatic transfer of customer’s
PDM data files and b) as automatic transfer of
customer’s database as one file with inclusion into
main server database.
The main server database collects the individual
customer databases with PDM parameters to form a
knowledgebase.
As for now, customer PDM data analysis and
transfer of the report from server is existing.
CONCLUSION
Remote PDM data analysis is a progressive and
cost-effective way for users to access powerful
scientific software. Software upgrades are done on the
server.
Remote data analysis allows an easy data
collection and data sharing which in turn leads to a
creation of knowledgebase opened for public analysis
and discussion.
PREVENTION OF PLANTAR FOOT TRAUMAS IN WEIGHT-LIFTING PRACTICE.
Velio Macellari (1), Carlo Varalda (2), Claudia Giacomozzi (1)
Dept. of Technologies and Health, Istituto Superiore di Sanità, Rome, Italy
Regional Commettee, Italian Federation of Physical Culture, Rome, Italy
RESULTS
As for maximum force perpendicularly acting on
the plantar surface of the foot, loads 2S, 2L, and loads
3S, 3L delivered comparable results, the difference
being 88.3 and 93.2N respectively. A greater
difference (160.9N) was found between loads 1L and
1S (unloaded condition).
Left foot peak pressures were 9, 9 and 17N/cm2
for the squat sequence, and 11, 12 and 18N/cm2 for the
leg press sequence. Corresponding right foot peak
pressures were 10, 12, and 24N/cm2, and 12, 12, and
22N/cm2. Mean pressures were also comparable: left
foot values were 3.8, 4.5, and 6.9N/cm2 for the squat
sequence, and 3.8, 4.9 and 6.6N/cm2 for the leg press
60kg
HORIZONTAL LEG PRESS
90kg
A well trained healthy subject (female, body
mass 44.5kg) was examined with the Pedar Mobile
System by Novel while performing a squat and a
horizontal leg press sequence, the last one commonly
used to train leg muscles under increasing loads. The
squat sequence was performed with the subject
unloaded (load 1S), 20kg loaded (load 2S), and 50kg
loaded (load 3S), the last one being within the range of
weights safely lifted by the subject. The corresponding
leg press sequence, commonly used to train weightlifters to perform the above squat sequence, was
performed with 60kg (load 1L), 90kg (load 2L) and
120kg (load 3L), respectively. Maximum force, area
and pressure, and mean pressure have been included in
this study for each foot and each loading condition.
SQUAT
120kg
sequence; corresponding right foot values were 4.5,
5.1 and 7.9N/cm2, and 4.4, 5.0 and 7.8N/cm2.
Interestingly enough, contact area asymmetry
almost disappeared under loads 3S and 3L, while force
asymmetry increased (left foot: 47.2% (load 3S) and
47.5% (load 3L) of the total force), thus increasing
left-right differences in peak pressures.
UNLOADED
Being the benefits of sport practice proved in a
wide range of age including evolutive age and elderly,
and in presence of various pathologies, attention
should be paid to the correctness of training tasks.
Their adaptability should be investigated to musculoskeletal structures which could have underwent
anatomical alterations and functional impairments due
to physiological growth, aging, orthopaedic or
neurological diseases, metabolic dysfunctions.
The present study deals with a preliminary
monitoring of foot-floor interaction during weight
lifting, aimed at investigating the loading pattern of
the plantar regions of the foot.
20kg
INTRODUCTION
50kg
1.
2.
Figure 1: Plantar pressure distribution under squat
and horizontal leg press loading sequence. Red lines
show the trajectories of center of pressure.
DISCUSSION AND CONCLUSIONS
The above data seem to confirm the correctness
of the training task in supplying the desired sequence
of increasing loads, but do not highlight a crucial
difference in the plantar loading pattern. As shown in
Figure 1, in fact, the leg press sequence heavily
involves forefoot region, while the correct squat task
mainly involves rearfoot. The training condition does
not correctly stress rearfoot structures, which may
reduce their ability of safely bearing load (Mueller,
2002). This preliminary study thus suggests that ad
hoc, assessment protocols might be of great help in
rendering sport practice safer and more effective.
REFERENCES
Mueller et al, Phys Ther 82(4):383-403, 2002.
PLANTAR OTHOSES: TOWARDS A BETTER DESIGN TO IMPROVE THEIR
EFFECTIVENESS IN DIABETIC ULCER PREVENTION.
Claudia Giacomozzi (1), Emanuela D’Ambrogi (2), Luigi Uccioli (3), Velio Macellari (1)
1.
2.
3.
Dept. of Technologies and Health, Istituto Superiore di Sanità, Rome, Italy
Podiatrist Training Unit, University of Tor Vergata, Rome, Italy
Dept of Internal Medicine, University of Tor Vergata, Rome, Italy
INTRODUCTION
Plantar orthoses are valuable tools to reduce
peak pressures at the plantar surface level, which
could otherwise concur to the formation of
neuropathic ulcers. Our study deals with the design of
plantar orthoses based on a deeper knowledge into the
way each material distributes pressure when it
undergoes different loading conditions, and of how
material aging interacts with its response. Two phases
of the study have already been concluded and a third
one is in progress. Main results are reported in the
following.
The first phase of the study started with the static
characterisation of 31 samples (10x10cm2, different
chemical composition and thickness) of on-the-market
materials commonly used to reduce plantar peak
pressures. Pressure distribution due to a cylindrical
load (12kg, circular loading surface 19.6cm2) was
measured below the tested material by using the
capacitive EMED St-4 pressure platform (Novel).
In the second phase of the study, one “rigid” and
one “elastic” material, which had shown more uniform
pressure distribution under static conditions, were
tested inside comfortable walking shoes (rubber sole,
heel 5cm) during daily locomotor tasks like level
walking and stairs negotiating. Pressure measurements
were taken by the Pedar Mobile System (Novel) at the
interface between foot and orthosis. Two volunteers,
one healthy subject and one diabetic neuropathic
patient with an incoming rigid pes cavus, were
acquired up to 100 footprints each, 50 for each foot.
In the third phase of the study, a couple of
insoles made of PPT plus plastazote, which best
managed the dynamic loading conditions, was given to
the neuropathic patient and its behaviour monitored
monthly. Peak and mean pressures under 1st, central,
lateral metatarsal heads, and whole metatarsal area
(MPP) were averaged over 8 footprints per foot, taken
during at regimen level walking.
RESULTS
First phase. The materials which best
reproduced the theoretic, low-peak pressure
distribution were basically three: artificial cork
(sugherite) 0.6cm thick, vulcanized expanded rubber
1cm thick, PPT plus plastazote 0.6cm thick.
Second phase. Peak pressures were best reduced
during all locomotor tasks by PPT plus plastazote
(Lemmon, 1997). Mean reduction was 25% (±14) for
the healthy subject and 43% (±12) for the neuropathic
patient (Perry, 1995). Surprisingly enough, sugherite
unbalanced the gait, sometimes even increasing
pressures during propulsion.
Third phase. MPP had a very limited variability
within each testing condition. Table 1 summarises
MPP values and the corresponding, time-decreasing,
percentage of pressure reduction. As for peak
pressures, a lower reduction was found under the 1st
metatarsal head (%reduction: 13.5 during last session,
27 during the first session). Under this area, PPT
thickness decreased of 0.5mm, plastazote of 2mm.
Session Without orth.
(N/cm2)
1
14.1 (±0.4)
2
16.0 (±0.5)
3
14.8 (±0.4)
With orth. Reduction
(N/cm2)
(%)
10.1 (±0.7) 28.5*
12.5 (±0.3) 22.3*
11.8 (±0.5) 21.7*
* statistically significant (t-Student’s test, p<0.001)
Table 1: MPP obtained during level walking without
and with plantar orthosis.
CONCLUSIONS
The study seems to be well designed for a
detailed characterisation of how, how much, and how
long plantar orthoses effectively manage pressure
distribution. Once the methodology is established,
hard work has still to be done to correctly relate
pressure reduction to orthosis consumption, and the
latter to various factors such as plantar rigid inserts,
shoes, body mass, locomotor habits.
REFERENCES
Lemmon et al, J Biomech 30(6):615-620, 1997
Perry et al, J Bone St Surg 77A:1819-1828, 1995
CHANGES OF FOOT LOAD AND FUNCTIONAL CHARACTERISTICS IN THE GROUPE OF OBESE
CHILDREN DURING REDUCTION OF WEIGHT
Kostelnikova Lenka, Hlavacek Petr
Department of Protein and Leather Technology, Faculty of Technology, Tomas Bata University
in Zlin, Mostni 5139, 762 72 Zlin, The Czech republic, [email protected]
OBJECTIVES
This study is focused on finding existence of
changes in foot proportions and changes in the
distribution of force in the sole during reduction of
weight in obese children.
foot is evidently able to compensate weight increase.
Also the distribution of pressure on the foot indicates
significant changes and this problem should be studied
in detail.
FIGURES
Along of five-week weight loss courses for
39 children and adolescents (24 girls, 15 boys) in the
age of 10 to 19 years, dynamic pressures were
measured between the foot and footwear insoles using
a Pedar instrument. The foot proportions were
measured by classical method and girth size was
analysed the first in loaded and the latter in unloaded
position (during sitting and standing subjects). The
results were evaluated with NovelWin software, which
enables the establishment of maximum pressures at
defined locations, the course of maximum force and
centres of gravity. The measurement was conducted
at the beginning of the course and after its completion.
RESULTS
The difference joint girth
METHODOLOGY
y = -0.5389x + 30.59
40
30
Left Foot
20
10
0
20
25
30
35
40
BMI
Figure 1: The difference of joint girth in loaded
and unloaded position dependence on BMI by left foot
Figure 2: The difference of joint girth in loaded
and unloaded position dependence on BMI by right
foot
CONCLUSION
REFERENCES
The study proves that relatively small
changes of weight had influence changes in width
girth values that can be considered as significant. Data
do not proved connection between obesity and
increased occurrence of foot deformities. The child
The difference joint girth
The average value of weight loss achieved
the average 3.31 ± 1.85 kg (3.22 ± 1.74 kg for girls
and 3.51 ± 2.18 kg for boys). From the extensive set of
measured data, changes were analysed in values of
maximum pressures in the frontal, arch and heel
sections on the surface of the foot at the beginning of
the experiment and at the end. The determined
differences demonstrated that there is the dependence
between the weight loss and the selected factors. Most
significant was the relationship between the weight
loss and girth changes at the metatarsophalangeal joint
(toe joint area) (Fig. 1, 2). This determined
dependency can be marked as highly significant in
regard to the values known to increase the number of
foot deformities and disease at the current child
population.
y = -0.7334x +
36.492
40
30
Right Foot
20
10
0
20
25
30
35
40
BMI
Hainer V., et. al, Obezita – etiopatogeneze,
diagnostika a terapie, 1997.
Svačina, Š., Obezita a diabetes, 2000.
MIGHT NORMALISATION TECHNIQUES IMPROVE THE CORRECTNESS OF
PLANTAR PRESSURE MEASUREMENTS?
Claudia Giacomozzi, Velio Macellari
Dept. Technologies and Health, Istituto Superiore di Sanità, Rome, Italy
INTRODUCTION
RESULTS
In order to compare inter-subjects gait
parameters, measurements need to be normalised.
Ground reaction force is commonly normalised with
respect to body weight. As for plantar pressure
distribution, instead, its absolute value is always
considered. Main reasons for that are basically two: a)
the greater the body mass (b.m.), the wider the loaded
surface, which renders pressure almost independent
from subject’s mass; b) high peak pressures may
damage tissues independently from subject’s
anatomical and functional structure.
The present study deals with the eventual
improvement of correctness and meaning of intersubjects pressure distribution comparisons by referring
it to an “ideal” pressure. Our basic observations were:
a) responses of same-size pressure insoles, inserted in
same-type shoes, do depend on the subjects’ mass; b)
tissue adaptation to high but continuous load (Mueller,
2002) may induce changes in tissue mechanical
properties and increase resistance to traumas. Being
these concepts accepted, a criterion was found to
normalise in-shoe plantar pressure distribution and a
technique applied to three volunteers, one of which
with a typical neuropathic foot. Preliminary results are
encouraging and are reported in the following.
Comparisons among inter-subject absolute and
normalised pressure differences were performed for
maximum (P1) and mean (P2) pressures under the
total foot, and maximum pressures (P3) and
pressure/time integrals (P4) under the metatarsals. All
differences were expressed as a percentage of the
maximum recorded value, and reported in Table 1 for
the left foot. Subject a) showed the lowest absolute
peak values.
The Pedar Mobile System by Novel was used to
acquire pressure distribution inside comfortable
walking shoes (rubber sole, heel 3.5cm). Subjects
were asked to walk back and forth along a 10m
walking path; on their way back, they were asked to
perform three forefoot lifting. Three volunteers
(female, same foot size) were examined: a) a diabetic
neuropathic patient, b.m. 61kg; b) a healthy subject,
b.m. 73kg; c) a professional ice-skater, b.m. 82kg. The
reference pressure (RP) was calculated for each
subject on the basis of her own weight and the insole
area. RP was compared with the ideal pressure (IP) of
2N/cm2 calculated for a reference female subject
(height 175cm, b.m. 65kg) (De Leva, 1996).
Maximum local pressures were then normalised
according to the ratio between IP and RP.
Subject:
b.m.
P1
P2
P3
P4
b vs a
16.4
abs
23.5
6.3
21.6
24.3
norm
-9.9
0.2
-10.5
9.3
c vs a
25.6
abs
norm
35.0
3.8
8.7
1.4
35.0
3.3
-29.9
-43.8
Table 1: Percentual absolute (abs) and normalised
(norm) differences between subjects b and a (first two
columns) and between subjects c and a. Left foot.
DISCUSSION
The hereby proposed normalisation technique
sensibly reduced inter-subject differences in terms of
maximum and mean peak pressures (>=10% and 5%,
respectively), and magnified the differences between
healthy and pathologic condition in terms of
pressure/time integrals: the highest integrals were
found, in fact, for neuropathic subject a), despite of the
lowest peak pressures. In this specific case, a
traditional screening test based on the detection of
absolute peak pressures might have underestimated
dangerous loading conditions (poor test sensitivity).
However, the hypotheses this study is based on are
still an open question. Work is still in progress to
validate them, and to eventually supply more effective
tools for the early detection of plantar surface traumas.
REFERENCES
De Leva, J Biomech 29(9):1231-1233, 1996.
Mueller et al, Phys Ther 82(4):383-403, 2002.
FOOT FUNCTION AND MORPHOLOGY IN DIFFERENT DIABETIC POPULATIONS
IN NEW ZEALAND.
(work in progress)
Uwe G. Kersting(1), Dieter Rosenbaum(2)
1. Department of Sport and Exercise Science, University of Auckland, New Zealand
2. Orthopedic Department, Westfälische Wilhelms-Universität Münster, Germany
INTRODUCTION
Simmons et al. (2001) showed that the
prevalence for type II diabetes in South Auckland was
7.5% in Europeans, 21.1% in Maori and 25.0% in
Pacific Islanders. Moore and Lunt (2000)
demonstrated an earlier onset of diabetes for Maori
and Pacific Islanders in New Zealand. In combination,
these observations indicate an increased risk for
diabetic complications including diabetic foot
syndroms in New Zealand’s population. The New
Zealand Health Strategy has identified 500 diabetes
related amputations yearly (39% of all non-trauma
induced amputations) resulting in inpatient costs of
5M$ per annum. Applications of pressure distribution
(PD) measurements clearly demonstrated structural
changes of the feet of diabetics (e.g. Cavanagh et al.,
1993). Veves et al. (1993) could demonstrate racial
differences in foot morphology between black and
white Americans, which also relate to PD parameters.
Therefore, it appears likely that the diabetic foot
problem presents differently in various ethnicities,
which might have implications for specialized
footwear.
The present study is therefore part of a long term
research project covering two research areas:
• Identification of differences in foot morphology
between ethnicities.
• Development and testing of footwear modifications
with emphasis on their effects on foot mechanics
and subsequent evaluation in clinical outcome
studies.
The current study addresses the first aspect: A
standardised and reliable foot assessment protocol is
proposed, which includes relevant parameters for
morphology and dynamic function of diabetic feet.
Proposed parameters are: static foot form, flexibility
status, muscle function, soft tissue function,
vascularity, diabetes history, neuropathy status and ??
METHODS
1) Static foot shape: From podometer prints various
static foot measures are derived to classify the foot
shape.
2) Dynamic PD measurements: Quantitative
information about the foot loading characteristics
during gait (Cavanagh et al., 2000). Local peak
pressures have been associated with the development
of ulcerations in neuropathic feet.
3) Muscle strength: Anderson et al. (1996) pointed
out the large differences between diabetics and healthy
controls regarding function of the leg and foot
muscles. An isokinetic dynamometer serves to
quantify muscle strength.
4) Muscle function during walking: Studies
addressing dynamic muscle function during gait
deliver unequivocal results. While Abboud et al.
(2000) have shown decreased activity of the tibialis
anterior in neuropathic diabetic feet during walking,
Kwon et al. (2003) demonstrated an increased
muscular activation in diabetics.
5) Muscle mass/cross sectional area: Bus et al.
(2002) provided the first quantitative data of muscle
atrophy using magnetic resonance imaging (MRI).
Their data show a 73% (!) decrease in muscle mass of
the foot in diabetics.
6) Soft tissue stiffness: The combination of muscle
atrophy and soft tissue degeneration have been
proposed as confounding factors in tissue overload in
diabetic feet (Bouten et al., 2003). Quantitative
information are obtained from MRI and mechanical
indentation tests.
7) Neuropathy status: Plantar sensitivity is
quantified using Semmes-Weinstein filament tests
(Perkins & Bril, 2003).
8) Diabetes history: Patient information data about
ethnical background, diabetes duration, existing
complications and quality of metabolic control are
collected.
PRELIMINARY RESULTS
At present data for 51 subjects have been
collected. Only a limited number of Maori and Pacific
Islanders have volunteered so far. The main focus
currently is to increase subject numbers from nonEuropean populations.
REFERENCES
Abboud, R. et al, Clin Biomech 15:37-45, 2000.
Bouten, C.V. et al, Arch phys Rehabil 84:616-619, 2003.
Bus, S.A. et al, Diab Care 25(8):1444-1450, 2002.
Cavanagh, P. R. et al, J.Biomech 26:23-40, 1993.
Cavanagh, P. R. et al, Diab Metab Res Rev 16, S6-10, 2000.
Kwon, O-Y. et al, Gait &Posture 18:105-113, 2003.
Perkins, P.A. & Bril, V., Clin Neurophys 114:1167-75, 2003.
Simmons, D. et al, Diabetes 18,193-198, 2001.
Veves, A. et al, Diabet Med, 12, 585-589, 1995.
Multi-segment foot motion during gait: proof of concept in rheumatoid
arthritis
Woodburn J1, Nelson KM2, Lohmann Siegel K2, Kepple TM2, Gerber LH2
1 Academic Unit of Musculoskeletal Disease, The University of Leeds, Leeds, UK;
2 Rehabilitation Medicine Department, Department of Health and Human Services,
National Institutes of Health, Bethesda, MD, USA.
Introduction:
Rheumatoid arthritis (RA) is associated
with the development of widespread and
severe foot impairments including pain,
stiffness and deformity. Previous 3D
motion analysis studies of the ankle joint
complex of the foot modelled as a single
rigid body have detected reduced range of
motion, rearfoot instability associated with
pes planovalgus, and loss of rocker
function associated with forefoot pain. This
study aims to extend this work by
developing and applying a multi-segment
kinematic foot model to RA and to
examine
the
relationship
between
abnormal motion and foot impairments.
Methods:
Five healthy adult subjects and 11 RA
patients with advanced disease were
studied. Foot impairments were assessed
using standardised outcomes and clinical
examination techniques. A six-camera
60Hz video-based motion analysis system
(Vicon 370, Oxford Metrics Group, Oxford,
UK) was used to measure motion of the
shank, rearfoot, forefoot and hallux
segments (segments defined according to
Carson et al [2001]) and the vertical
displacement of the navicular. Face
validity and estimates of repeatability were
determined.
Motion
patterns
were
calculated using Visual3D software (Cmotion, Inc., Rockville, MD, USA) and
comparisons were made between normal
and RA subjects. Relationships between
clinical impairment and abnormal motion
were determined through inspection of
individual RA cases.
Results:
Across the motion variables, the withinday and between-day coefficient of
multiple correlation values ranged from
0.677-0.982 for the normal subjects and
0.830-0.981 for RA patients. Based on
previous studies, motion parameters for
the normal subjects showed excellent face
validity. In RA patients, there was reduced
range of motion across all segments and
all planes of motion which was consistent
with joint stiffness. In the RA patients,
rearfoot motion was shifted towards
eversion and external rotation and peak
values for these variables were increased,
on average by 7° and 11° respectively.
Forefoot range of motion was reduced in
all three planes (between 31-53%), but the
maximum and minimum angles were
comparable to normal. The navicular
height, during full foot contact, was on
average 3mm lower in the RA patients in
comparison to normal. The hallux was less
extended in the RA subjects in comparison
to normal (21° versus 33°) during the
terminal stance phase. Individual cases
showed abnormal patterns of motion
consistent with their clinical impairments,
especially those with predominant forefoot
pain or pes planovalgus.
Discussion:
This study offers new preliminary evidence
to suggest that multiple inter-segment
motion changes occur in the RA foot and
that these are consistent with impairments
(pain, deformity and stiffness) as a result
of the underlying inflammatory disease
process. The rearfoot was unstable and, in
cases with pes planovalgus, associated
with abnormal motion in the forefoot and
medial arch. Stiffness was readily detected
throughout the foot, especially at the
hallux, and this agrees with the high
prevalence of pathology at this site. Other
cases with severe forefoot pain showed
motion changes consistent with protective
mechanisms to off-load inflamed joints.
Technical limitations, in part related to RA,
were noted including anatomical landmark
location error at sites of foot inflammation
and swelling.
Conclusion:
In RA, multi-segment foot models may
provide a more complete description of
foot motion abnormalities where pathology
presents at multiple joints leading to
complex
and
varied
patterns
of
impairment. This technique may be useful
to evaluate functional changes in the foot
and to help plan and assess logical,
structurally based corrective interventions.
DEBRIDEMENT OF PLANTAR CALLOSITIES IN RHEUMATOID ARTHRITIS:
A RANDOMISED CONTROLLED TRIAL
Davys H.J.1, Turner D.E.2, Helliwell P.S.2, Conaghan P.G.2, Emery P.2, Woodburn J.2
1
Foot Health Department, The Leeds General Infirmary; 2Academic Unit of Musculoskeletal Disease,
The University of Leeds, Leeds, UK.
Objective:
To compare forefoot pain, pressure and function
before and after normal and sham callus
treatment in rheumatoid arthritis (RA).
Patients and methods. 38 RA patients were
randomly assigned to normal (NCT group) or
sham (SCT) scalpel debridement. The sham
procedure comprised blunt-edged scalpel paring
of the callus which delivered a physical stimulus
but left the hyperkeratotic tissue intact, the
procedure partially obscured from the patient.
Forefoot pain was assessed using a 100mm VAS,
pressure using a high-resolution foot pressure
scanner and function using the spatial-temporal
gait parameters measured on an instrumented
walkway. Radiographic scores of joint erosion
were obtained for metatarsophalangeal (MTP)
joints with and without overlying callosities. The
trial consisted of a randomised sham-controlled
phase evaluating the immediate same day
treatment effect and an unblinded 4 week followup phase.
Results:
During the sham-controlled phase, both groups
showed a very small improvement in forefoot pain
following intervention, however, no statistically
significant between-group difference was found
(p=0.48). Daily and weekly pain scores improved
in both groups during the unblinded phase but
there were no statistically significant differences at
any of the review points. Peak pressures were
slightly decreased in the NCT group and
moderately increased in the SCT group, but there
was no statistically significant between-group
difference (p=0.16). The area of and duration of
contact of the callus site on the ground remained
unchanged following treatment in both groups. In
both groups, the walking speed was moderately
increased, the stride-length longer and the doublesupport time shorter following intervention.
However, between-group differences did not
reach levels of statistical significance. MTP
joints with overlying callus were significantly
more eroded than those without (p=0.02).
Conclusions:
Treatment of painful plantar callosities in
RA using scalpel debridement lessened
forefoot pain but the effect was no greater
than sham treatment. Localised pressure or
gait function was not significantly improved
following treatment.
OFF-THE-SHELF CONTOURED ORTHOSES DEMONSTRATE COMPARABLE
MECHANICAL PROPERTIES TO CUSTOM-MADE FOOT ORTHOSES AT LESS COST
Anthony C Redmond, MSc 1*, Karl B Landorf, BSc 2, Anne-Maree Keenan, M App Sci 1 and Paul Emery,
MBBCh, MD, FRCP 1
1
Academic unit of Musculoskeletal Disease, University of Leeds, Leeds, W. Yorks, United Kingdom and
School of Exercise and Health Sciences, University of Western Sydney, Sydney, New South Wales, Australia.
2
Background:
Foot orthoses are reportedly helpful to patients
with certain musculoskeletal conditions [1,2].
Orthoses may be made from individual casts of
the patient s foot (costing ~£150), or supplied
off-the-shelf (OTS) (costing ~£5-£45). We have
demonstrated previously that the mechanical
properties of single plane OTS wedges (costing
~£1) are not comparable with custom devices
[3]. This study investigates contoured OTS
devices.
Methods:
Anatomically localised plantar pressures and
forces were measured in-shoe in 15 participants
with planus feet in a randomised, crossover trial,
comparing each orthosis type to the other, and
to a shoe-only control state. Participants were
randomised to one orthosis type, and after two
weeks of wearing orthoses, pressure and force
data were recorded using the Pedar system
(Novel GmbH, Munich). After crossover and a
further two weeks, pressures were re-recorded.
Orthoses were either customised polypropylene
devices, or a commercially available OTS device
made of the same materials but to a standard
last.
Results:
Both OTS and CFO devices produced
statistically
significant
and
comparable
mechanical changes relative to the control state
for 11 of the 35 variable/mask combinations.
The CFO and OTS devices did not differ
statistically from each other for any of the
variable/mask combinations. Pressure and force
variables are reduced significantly at the forefoot
(up to 37% change) and heel (up to 17%
change) while wearing either type of device, with
loads shifted to the midfoot (up to 34% change).
Differences were greatest for pressure and force
variables incorporating timing of load (integrals),
and both types of orthosis increased the
duration of load at the midfoot.
Conclusions:
Both custom and OTS orthoses shift load from the
forefoot and rearfoot toward the midfoot,
compared to the control state. The shift in load is
however associated with a concomitant increase
in midfoot contact area, minimising change in
pressures. The timing is altered by the addition of
a fulcrum at the midfoot, prolonging loading in this
area. Although the mechanical effects of the two
devices differed by no more than 12%, the final
total cost of CFO devices was more than double
that of OTS devices.
These objective data question the role of CFOs as
a first line treatment. While previous work has
suggested that single-plane OTS orthoses cannot
be considered a mechanical alternative to custom
orthoses, contoured OTS devices may address
some of the short-comings of single plane devices.
1. Landorf et al (2000). Efficacy of foot orthoses.
J Am Pod Med Assoc
2. Woodburn et al (2002) A randomised controlled
trial of foot orthoses in RA. J Rheumatol
3. Redmond et al (2000). Effect of cast and noncast foot orthoses. J Am Pod Med Assoc
SAGITTAL THICKNESS OF THE PLANTAR FASCIA IS RELATED TO STATIC
ARCH SHAPE AND REGIONAL LOADING OF THE FOOT IN PLANTAR FASCIITIS.
Scott. C. Wearing (1), James. E. Smeathers (1), Bede. Yates (2), Patrick. M. Sullivan (2),
Stephen. R. Urry (1), Philip. Dubois (2)
1. Centre for Health Research, Queensland University of Technology, Qld, Australia
2. Queensland X-ray, Mater Private Hospital, Brisbane, Qld, Australia
Previous research has found the thickness of
plantar fascia to be directly correlated with vertical
force beneath the forefoot in diabetes (D'Ambrogi et
al., 2003). Given that increased fascial thickness is
also prototypic of plantar fasciitis (Gibbon and Long,
1999), this study investigated whether the same
relationship was evident in subjects with plantar
fasciitis.
METHODS
Ten subjects (3 male and 7 female) with
unilateral plantar fasciitis (age = 48 ± 12 yrs; height =
1.67 ± 0.09 m; weight = 79.3 ± 10.2 kg) and 10
control subjects, matched for age, gender and body
weight (age = 47 ± 12 yrs; height = 1.68 ± 0.11 m;
weight = 81.6 ± 10.6 kg), participated in the study.
The mean duration of heel pain was 9 ± 6 months.
The sagittal thickness of the plantar fascia was
measured from non-weightbearing sonograms of each
foot acquired with a variable frequency 12-5 MHz
linear array transducer (HDI 5000, Advanced
Technology Laboratories, Bothel, Washington, USA).
The arch angle, a static measure of arch shape, was
also determined based on standard lateral
roentgenograms acquired bilaterally during stance.
Regional forces beneath the heel, midfoot, forefoot
and digits were estimated from plantar pressure
measurements (EMED-SF, Novel GmbH, Munich,
Germany) obtained while subjects completed three
walking trials at their preferred pace. The magnitude
of heel pain was measured with a visual analogue pain
scale (Pain Relief Foundation, Liverpool, England).
Relationships between the sagittal thickness of the
plantar fascia, the regional loading of the foot and
static arch shape were investigated in each group using
correlations. An alpha level of 0.05 was used for all
tests of significance.
FINDINGS
The plantar fascia of the symptomatic limb was
48% thicker than its asymptomatic counterpart (P <
0.05) and 57% thicker than the fascia of the matched
control limbs (P < 0.05). Significant correlations were
noted between the magnitude of pain, estimated via a
visual analogue scale, and fascial thickness (r = 0.68,
P < 0.05), pain and midfoot loading (r = 0.76, P <
0.05) and pain and arch angle (r = 0.76, P < 0.05) in
the symptomatic limb, only.
9
Fascial Thickness (mm)
BACKGROUND
Symptomatic
Asymptomatic
Control (S)
8
Control (A)
Symptomatic
7
6
5
Asymptomatic
4
Control (A+S)
3
2
1
0
110
115
120
125
130
135
140
145
Arch Angle (º)
Figure 1: Fascial thickness as a function of arch angle
in symptomatic, asymptomatic and control limbs.
Fascial thickness was positively correlated with
the arch angle in symptomatic (r = 0.89, P < 0.05) and
asymptomatic (r =0.64, P < 0.05) feet of heel pain
patients (Figure 1). The thickness of the symptomatic
plantar fascia was positively correlated with the
maximum force beneath the midfoot of the
symptomatic limb (r = 0.79, P < 0.05), as well as the
peak force beneath the midfoot (r = 0.73, P < 0.05)
and forefoot (r = 0.66, P < 0.05) of the asymptomatic
limb. Control subjects had no significant correlations
between the sagittal thickness of the plantar fascia, the
arch angle and the regional loading of the foot.
INTERPRETATION
Sagittal thickness of the plantar fascia is related
to both the loading and the static shape of the arch in
subjects with plantar fasciitis. While the effect is not
evident in subjects without plantar fasciitis, it is
unknown if these physical characteristics contribute to
the development of plantar fasciitis, or occur as a
result of heel pain.
REFERENCES
D'Ambrogi et al, Diabetes Care 26:1525-1529, 2003.
Gibbon and Long, Skeletal Radiol 28:21-26, 1999.
HOW TO EVALUATE A RESULT IN CONSERVATIVE FLATFOOT SURGERY WITH
DYNAMIC PEDOBAROGRAPHY ANALYSIS ?
Eric Toullec
Polyclinique de Bordeaux, Bordeaux, France
BACKGROUND
In flexible flatfoot stage 2-3, conservative surgical
treatment is generally indicated. The results are often
evaluated only by a static exam like X-ray but rarely
by a dynamic approach. We related a comparison
study of flatfoot before and after surgery with a
dynamic pedobarography analysis ( emed –SF).
METHODS
20 feet (18 patients ) were analysed by photographs in
three views , X-ray and dynamic footprint with a
platform before and after a Evan’s calcaneal
lengthening osteotomy associated with medial arch
reconstruction.
FINDINGS
In the first time , we defined the characteritic points of
flatfoot but no criterion was found in all cases : wide
midfoot ( 60%), Hindfoot valgus (70%) , forefoot
abductus (60%) , hallux valgus (50%) and a 1rst
metatarsal head overpressure (80%). On the graph , we
note in the most cases , the peak of maximum pressure
during tiptoe, the disappearance of the double dome
on the force graph showing the sagging of the medial
arch no compensed by the uppering force of the
opposite lower limb during the stride and an area
graph very high and during a long load time.
Another criterion was the ratio lateral force/medial
force which is between 0.5 to 0.9 showing that the
sagging of the medial arch induce a medial force with
the consequences on the opposite lower limb .
After surgery , we were happily surprised by the good
modification of the footprint but the question was :
what criterion we have to choose to evaluate our
results ?
The 1rst metatarsal head overpressure decrease in all
cases and was easily seen on the print. For the midfoot
width and the hindfoot valgus , we use the groupmask
evaluation. But for the hallux valgus and the forefoot
abduction it was more difficult to measure the
modification of these angles. On the other hand , the
ratio lateral force / medial force give a good
evaluation of the result compared with the clinical
result.
INTERPRETATION
The pedobarography analysis was interressing to guide
the postoperative period with physiotherapy (
strengthening of the flexor digitorum tendon when no
pressure above the toes for exemple) and the
confection of insoles. It allows also the comparison of
different prints with the time interressing to give a
prognosis.
CONCLUSION
We think it is necessary to define the main criterion to
evaluate our result in surgery. In the case of the
flatfoot , we choose six : midfoot width , hindfoot
valgus , forefoot abduction , hallux valgus , 1srt
metatarsal head overpressure and the ration lateral
force/ medial force.
REFERENCES
Oeffinger DJ et al, 2000. Foot pressure and
radiographic outcome measures of lateral column
lengthening for pes planus deformity . Gait Posture .
12 (3) :189-195.
Davitt JS et al ,2001. Plantar pressure and
radiographic changes after distal calcaneal lengthening
in children and adolescents. J.Pediatr Orthop , 21 (1 ):
70-75.
DETECTING THE PRESENCE OF FUNCTIONAL HALLUX LIMITUS USING
DYNAMIC FOOT PRESSURE
S. Khamis (1), Z. Yizhar (1)(2)
1. Gait and Motion Laboratory, Pediatric Orthopedic department, Dana Children Hospital,
Tel-Aviv Medical Center, Israel.
2. Department of Physical Therapy, Sackler Faculty of Medicine, Tel-Aviv University.
INTRODUCTION
RESULTS
Traditional instrumented gait analysis considers
the foot as one rigid segment, however foot
dysfunctions indicate otherwise. A common cause for
sagittal plane blockage is functional limitation of dorsi
flexion motion at the 1st metatarsal phalangeal joint
(Danneberg) that disrupts the 3rd foot rocker (Perry).
The reason for this limitation is known as
"windlass mechanism", based on the biomechanical
properties of the plantar fascia (Hicks). This foot
dysfunction is usually examined statically in the
clinical setting.
Both methods were correlated to hindfoot
measurements position (r = .456-.595; p = .043-.006)
in mild pronation. However, in severe pronation,
significant correlation was found only with the
method based on foot axis and the center of pressure
alignment (r=. 457; p=.043). Hyperpronation was
found to be correlated with big toe time pressure
integral and peak pressure (r=.473-.434; p=.001-.003),
and with 2nd metatarsal head peak pressure (r=.334;
p=.027). However, no correlation was found with 1st
metatarsal head pressure time integral or peak
pressure.
Based on our data, detecting the presence of
functional hallux limitus was not validated.
OBJECTIVE
The purpose of this study is of two folds:
1. Determining foot function in the dynamic setting.
2. To detect the presence of functional hallux limitus
phenomenon in dynamic mode, using foot pressure
system.
METHODS
22 subjects (12 males 10 females; age 16-57 y;
height 155-200 cm, weight 54-95 kg) that have been
referred to the gait lab for foot evaluation participated
in the study. They were asked to walk at a customary
walking speed over EMED pedobarograph platform
by NOVEL Co, embedded in the lab’s 12 m walkway.
Two-foot pressure measurements were taken for each
leg.
Dynamic foot function was determined by two
methods: 1. The ratio between lateral to medial foot
contact area. 2. The ratio between lateral and medial
areas enclosed between foot axis and center of
pressure. Both methods were expressed relative to the
static measurement of hind foot position in standing,
position in which subjects function about during
walking (McPoil et al).
The relationship between functional hallux limitus
and dynamic foot pressure data (peak pressure,
pressure time integral and contact time for big toe, 1st
metatarsal head and 2nd metatarsal head) was checked
by Pearson’s correlation coefficient and the
significance level was set at p<. 05.
CONCLUSIONS
The valid method to determine dynamic foot
dysfunction should be based on the center of pressure
in respect to the foot axis.
Dynamic foot pressure provides data which
supports the presence of functional hallux limitus, but
definitive diagnosis should incorporate movement
detection. This seems to be due to the functional
versatility of the foot (Kappel-Bargas et al) and its
various compensatory functional capabilities.
REFERENCES
Dananberg HJ, J Am Podiatr Med Assoc 83(8):43341, 1993.
Perry J, Gait Analysis: Normal and Pathological
function, 1992.
Hicks JH, J Anat 88(1):25-30, 1954.
McPoil T et al, J Orthop Sports Phys Ther 23(6):3705, 1996.
Kappel-Bargas et al, Clin Biomech 13(3):190-194.
1998
Changes in the plantar pressure patterns
after correction of hallux valgus deformity with the Scarf osteotomy
Timo J. Lorei, Dieter Rosenbaum, Hans Klärner, Christian Kinast*
Movement Analysis Lab, Orthopedic Department, University Hospital Münster, Germany,
[email protected] *Private Practice of Drs. Kinast, Hamel & Reisner, Munich
INTRODUCTION
Pressure distribution measurements are an accepted
tool for the evaluation of the effects of forefoot
corrections. Previous studies showed changes in
foot loading characteristics after hallux valgus
surgery (DeFrino 2002, Kernozek 2003). The aim
of the present study was to compare the plantar
pressure patterns before and after surgery of hallux
valgus deformities with the Scarf osteotomy for the
operated and contralateral foot.
feet. The peak pressure was slightly higher for
nearly every region of both feet with only few
significant differences (Fig.2). The impulse was
lower in the lateral metatarsals and in the hindfoot
and midfoot regions but higher in the hallux, toes
and medial metatarsals regions, (not significant in
every region; Fig. 2). Correlation analyses revealed
an influence of the plantar pressure changes of the
operated foot on the changes of the non operated
foot.
METHODS
Thirty-two subjects with unilateral hallux valgus
deformity were operated with the Scarf osteotomy.
The patients were examined and x-rayed before and
on average 33 months after surgery and were asked
to walk at self-selected speed across a capacitive
pressure platform, embedded in the floor (Novel
ST-4, 4 sensors/cm2, 50 Hz). Additionally the
patients were questioned postoperatively about their
subjective satisfaction with the outcome.
Plantar pressure patterns were analyzed concerning
peak pressure, force, impulse, contact area and
contact time for ten regions of the foot (hindfoot,
midfoot, metatarsals 1-5, hallux, second toe and
lateral toes). Comparisons between the pre- and
postoperative plantar pressure patterns were
evaluated with the Wilcoxon signed-rank test.
In conclusion, the results demonstrate that the
hallux and medial metatarsals of the operated feet
become more actively involved in the dynamic foot
movement after hallux valgus surgery with the
Scarf osteotomy. The analyses of the hallux and the
medial metatarsals regions of the contralateral foot
show the same tendency.
REFERENCES
• Kernozek T.W. et al. (2003) J American
Podiatric Medical Association, 93 (2): 97-103
• DeFrino Pf. et al. (2002) Foot Ankle Int.
2002;23(6):496-502.
ACKNOWLEDGEMENTS
Thanks are due to Novel Munich and the practice of
Dr. med. Kinast, Prof. Hamel, Dr. med. Reisner in
Munich for their support.
90% of the patients were satisfied with the surgical
outcome. Hallux valgus and intermetatarsal angles
were significantly reduced (Fig. 1). Postoperatively,
the maximum force was significantly higher in the
hallux, toes and medial metatarsals regions for the
operated foot as well as the contralateral foot. In the
same regions, the contact areas were larger in both
Fig. 2: overview of the significant pedobarographical
parameters of the operated foot.
Fig. 1: Intermetatarsal angle and hallux valgus
angle before and after surgery.
THE IMPACT OF EXERCISING ON SCHOOL CHILDREN WITH VALGUS HEEL AND
FLATFEET
Jitka Baďurová, Hana Samsonová
Faculty of Technology, Thomas Bata University in Zlín, Czech Republic
Institute of Protein and Leather Technology
INTRODUCTION
Flatfeet and valgosity are two of the most
frequent illnesses associated with children's feet. (1)
These two illnesses are closely related. It has been
generally observed that flatfeet are a manifestation
linked to valgosity.
Currently, these illnesses are commonly treated
by passively prescribed commercially produced
orthopedic inserts. The problem is that many
functionally normal feet are treated unnecessarily,
while a number of serious flatfoot cases are treated
insufficiently. (2)
Since the inserts passively support the
longitudinal arch, the muscles in the foot are flaccid.
(3) Therefore, it was decided to begin a study, which
would focus on the importance of exercise and the
training of foot muscles to maintain a healthy foot.
EXPERIMENTAL
In January 2004 were measured (using the Pedar
system) second + third grade children’s feet from
basic school in Zlin. In total we had 93 subjects, 35
children were suffering from valgus heel and almost
one third of those from flatfoot as well. During the
next 3-month the 35 ill subjects underwent special
training focused on the revitalization of muscles in the
feet. After this training they were again measured on
the Pedar.
With the use of Novel software we divided the
sensorial insole into four masks and evaluated the
change of mean peak pressures.
First we compared the foot pressures of the ill
group with the other subjects examined. And second,
we evaluated the changes in pressure among children
suffering from valgosity and flatfeet before and after
training.
We presumed that the improvement of valgosity
and flatfoot would be indicated by the shift of the load
on the sole from medial to lateral sides. And it was
proven to be true in almost 70% of tested subjects,
who underwent foot muscle training.
On the other hand, regarding the comparison of
peak pressures between valgous subject and subjects
with negative determination of valgosity and flatfoot,
it cannot be said, that there is any difference in loading
the sole.
CONCLUSION
Without a doubt, the development of children's
feet can be affected and corrected by suitably selected
foot muscle training and vice versa. The acquired
results, however, describe only a short period, which
does not enable us to prove the real affects of
exercising. Definitive conclusions will only be
possible to formulate after a longer experiment period.
REFERENCES
1. Hlavaček, P., Šťastná, P., Majerová, V.: Frequency
of occurrence of disturbances on children feet, PZTM/23. VÚT Brno, FT Zlín, (2000)
2. Dungl, P: Orthopedics and traumatology. Praha :
AVICENUM (1989)
3. Pavlis, S.: Flat foot, Ústav zdravotnej výchovy,
Bratislava, 1992. ISBN 80-7159-007
THE PROBLEM OF FOOTWEAR FOR WOMEN IN THE FINAL TERM OF
PREGNANCY.
Martina Cernekova, Petr Hlavacek
Institute of Protein and Leather Technology, Faculty of Technology, Tomas Bata University
in Zlín, Czech Republic
INTRODUCTION
Improvements to diagnostic and measuring
instruments have enabled the performance of such
studies and the monitoring development in situations
and conditions in ways not previously possible. One
such typical example is the change in the movement of
women during pregnancy. The idea for conducting this
study was to determine at which point during
pregnancy does stability in movement change and
whether it is possible to affect this problem with
suitable footwear. At the same time, the goal was to
test whether wearing special prophylactic footwear for
diabetics applies during this period. The Institute of
Protein and Leather Technology has long worked on
the development and testing of this footwear.
During the working hypothesis, we began from known
studies, from which it appeared that over the course of
pregnancy, the joints of the lower limbs and the pelvic
joint become less strong and flexible as a result of the
action of pregnancy hormones. Loosening of the hip
and knee joints as well as changes in the spine also
occur. The foot of a pregnant woman is anatomically
adapted to a certain weight, but the weight increases
during pregnancy. All of these factors result in
walking becoming uncertain and with increasing
stages of pregnancy, it becomes even more difficult.
Shoe wear for women during pregnancy is a
chronically neglected problem. This demonstrates that
in the case of footwear, fashion is the most powerful
factor subjecting the predominant sector of the
population even though this may be linked with
discomfort and inconvenience.
EXPERIMENTAL
Naturally, in the first term of pregnancy, it is
unnecessary to speak of special footwear
requirements; not until the second term does the
gradual inclination begin to manifest itself for women
toward comfort and this reaches a peak in the third
term. For our experiment, 9 subjects were selected on
the basis of a recommendation by the treating
physician from the Gynaecological – Obstetrics Ward
of the Bata Hospital in Zlín. The average age was
28.33 year, the average weight at the beginning of the
third term was 68.5 kg and up to the birth, their weight
increased on average by 8.7 kg.
Walking shoes of a derby cut were selected for testing.
The upper consisted of leather and the lining was
textile. An inserted insole was of foam latex with a
stabilizer heel and the sole was made of rubber.
Closing the footwear was resolved by lacing or a
Velcro system. The tested footwear was in number
size ranges from 230 to 265.
Measurement of changes to internal girth was
conducted according to the BL1 method developed at
the Institute of Protein and Leather Technology in
Zlín. Using this measurement, it was possible to
determine how fast and to what degree footwear is
capable of adapting to individual foot shapes, which is
critical from the standpoint of comfort when walking.
The footwear was given to the subjects after
determining the initial values of internal girth at the
location of greatest movement. This measurement was
considered to be zero and approximately after every
ten hours of wear, further measurements were taken.
The same procedure was repeated for a period of six
weeks. Measurement of tread pressure was conducted
on a PEDAR® instrument.
CONCLUSIONS
Footwear that respects changes in the foot and
movement activities of pregnant women has been
experimentally confirmed. In research conducted by
means of questionnaires, used footwear was very
highly evaluated also according to subjective feelings
during wear. Women indicated that during the use of
this footwear, there was a lessening of problems
related with pregnancy, such as foot and back pain and
foot swelling. This study is presented here as an
introduction and we will continue to be engaged in the
problem of suitable footwear for pregnant women and
to monitor the measured quantities for a greater set of
subjects
REFERENCES
Fuchs, Nemoci v těhotenství. Praha: Avicenum, 1985.
Bavor, et al, Foof Arch in Gravidity. Universitas
Caroline Prafensis 1977
Dráč, et al, Trvalé zmeny po tehotnosti. Martin,
Osveta, 1992
Čech, et al, Porodnictví I, II. Praha, Grada Publishing
1999
Dynamic calibration and frequency response of capacitive film printed
transducers
Nicola Paone, Lorenzo Scalise
[email protected], [email protected]
Università Politecnica delle Marche, Dipartimento di Meccanica,
via Brecce Bianche, 60131 Ancona, Italia
There is large interest towards the possible use of capacitive pressure sensors for the measurement
of contact pressure between hand and handle, during tests of hand-held vibrating tools; such an
interest is motivated by the actual limitations of existing measurement devices, which do not allow
the measurement of grip force during the vibration tests of tools, even if it is widely recognised that
such quantity has a relevant influence on the results (see for example the series of norms ISO-8662,
which states that the measurement of grip force during the test would be desirable).
In this context, the european project VIBTOOL - "Grip-Force Mapping for Characterisation of
Hand-Held Vibrating Tools"( http://mm.univpm.it/vibtool/intro.html ) is developing sensors for that
purpose, in the form of capacitive pressure sensor matrices and gloves. Such sensors are intended to
measure pressure distributions in static and dynamic conditions, so to allow computation of push
and grip forces and possibly to measure the dynamic inputs to the hand-arm system, so to open the
possibility of impedance and energy flux measurements.
Here we present the experimental study of the dynamic performance of a single sensor over a
matrix.
The experiments are conducted by impact hammer excitation, which is used to apply a known force
input to the sensor, by means of a small coupling plate made of steel. In order to measure Frequency
response Functions (FRF) it is necessary the simultaneous acquisition of input force and output
from the sensor; this requires the exact synchronization of the two analog-to-digital (ADC)
converters employed by the measurement systems. An external clock has been chosen to drive both
the 16 bit ADC of the spectrum analyser used to register the input force and the 8 bit ADC
employed by the capacitive sensor electronics; a simultaneous sampling rate up to 5kHz was
obtained, which is sufficient for studying the FRF in the band of 2.5 kHz. The time window length
was 1024 samples, no windowing was applied.
The data are post processed to compute averaged FRFs in terms magnitude and phase plots. The
data are grouped according to peak input pressure. FRF plots show that the sensor response is
highly damped and no resonance peaks are observed. Taking into account a -3 dB attenuation, the
frequency bandwidth is rather large, in the range of several hundred Hertz, with a linear phase shift.
Therefore the sensor proves to be suited to perform dynamic measurements in a range of
frequencies that includes a large variety of vibrating tools.
Acknowledgement: “This work has been financed (or partly financed) by the EU Commission,
within the research contract VIB-TOOL (contract n. G6RD-CT-2002-00843), coordinated by Univ.
Politecnica delle Marche and having partners National Research Council of Italy-CNR, National
Research and safety Institute for Prevention of Occupational Accidents and Diseases-INRS, Novel
GmbH, University of Southampton, Hauptverband der Gewerblichen Berufsgenossenschaften e.V.,
Breakers A/S.”
BIOMECHANICAL ASSESSMENT OF THE STRUCTURE AND FUNCTION OF
BIRKENSTOCK FOOTBED TECHNOLOGIES
Laura E. Bray (1,2), Howard J. Hillstrom (1,2), Esther H. Kim (2), Benjamin P. Heilman (2),
Jinsup Song (2)
1. Temple University School of Podiatric Medicine, Pennsylvania
2. Drexel University, Pennsylvania
The purpose of this study is to evaluate the
structure of Birkenstock footbed technologies
(sandals, clogs, and shoes) and their effect on foot
function. The vast majority of shoe biomechanics
research has been performed on athletic shoe gear
especially running shoes (Cavanagh 1987; Stacoff et
al. 1991; Stacoff et al. 2001; Mundermann et al. 2003;
Nigget al. 2003). Some investigators have indicated
that the structure of the shoe may have a profound
effect upon its function (Stacoff et al. 1991; Hillstrom
2002). To further confound this issue it appears that
the biomechanical function of the foot is also
dependent upon the foot’s structure (Song et al. 1996).
METHODS
Torsional Flexibility By Arch Height
R=0.792
9
8
7
6
5
4
Fulda
Arch Height
Arizona
Pronounced
3
Arizona
Sof t
A mixed effects analysis of variance (ANOVA)
was used to test for significant differences in torsional
flexibility amongst the shoe models. The ANOVA
yielded a P value <0.0001 for this comparison. The
Land’s End shoe was the most flexible and the
London was the stiffest as distinguished by
Bonferroni-Dunn testing.
Figure 1 displays the
The shoes under evaluation exhibited different
torsional flexibilities as well as plantar loading during
gait. More research is needed to understand the
relationship between shoe structure and foot function.
Iceland
RESULTS
DISCUSSION
Sant a Cruz
This study encompassed a biomechanical
assessment of the structure and function of nine shoe
models.
Five Birkenstock sandals (Santa Cruz,
Iceland, Arizona Soft, Arizona Pronounced, and
Fulda), one clog (Boston), and one shoe (London)
were included. A New Balance walking shoe (573)
and a leather oxford (Land’s End) were included for
comparison. Shoe sizes spanned from 36 to 44
(European). Two experiments were performed in this
study: (1) torsional flexibility assessment of the right
shoe of each model and (2) in-shoe plantar pressure
assessment during comfortable cadence locomotion.
The torsional flexibility assessment was
performed with a custom jig in an Instron 4201
structural testing machine. The slope of the angle
versus moment curve served as the torsional flexibility
about the long axis of each shoe model.
Ten healthy subjects (6 female, 4 male) with
flexible pes planus feet were include. The Pedar inshoe system measured plantar pressures in each shoe
condition. A mask was developed (Multimask) to
analyze peak pressures, forces, and pressure–time
integrals beneath the hallux, first metatarsal
phalangeal joint (MTPJ), and second MTPJ.
inverse relationship between torsional flexibility and
arch height of the five sandals studied. The higher the
sandal’s arch height the lower its torsional flexibility.
Torsional Flexibility
INTRODUCTION
Figure 1: Inverse relationship of torsional flexibility
(°/N-m) versus arch height of Birkenstock sandals.
The highest arch height sandal is on the right.
P values
Hallux
1st MTPJ
2nd MTPJ
Peak Pressure
0.0408
<0.0001
0.0191
Maximum Force Pressure-time Integral
0.0094
0.0019
<0.0001
0.0005
0.1584
0.0353
Table 1: P values for peak pressure, maximum force,
and pressure-time integral across the nine shoe
models at the hallux, first MTPJ, and second MTPJ.
REFERENCES
Cavanagh, P. R. Foot Ankle 7(4): 197-217, 1987.
Hillstrom, H. et al. Gait And Posture 12(2), 2002.
Mundermann et al. Clin Biomech 18(3): 254-62, 2003.
Nigg et al. J Biomech 36(4): 569-75, 2003.
Song, J et al. JAPMA 86(1):16-23, 1996.
Stacoff et al.Med Sci Sports Exerc 23(4):482-90,1991.
Stacoff et al Med Sci Sports Exerc 33(2):311-9, 2001.
CASTING METHODS AND PLANTAR PRESSURE
‘THE EFFECTS OF CUSTOM MADE FOOT ORTHOSES ON PLANTAR PRESSURE DISTRIBUTION’
Nick Guldemond (1a), Pieter Leffers (2), Antal Sanders (1b), Hans Emmen (1b), Nicolaas
Schaper (1c), Geert Walenkamp (1a)
1. a) Orthopaedic Surgery, b) Rehabilitation Medicine, c) Internal Medicine. University Hospital
Maastricht, The Netherlands
2. Fac. Medicine, Dept. Epidemiology, Maastricht University, The Netherlands
BACKGROUND
Custom-made foot orthoses are widely used to
treat various problems of the feet. No publications
regarding differences in plantar pressure distribution
resulting from different casting methods for the
construction of custom-made foot orthoses have been
found.
METHODS
Four casting methods were used for construction
of accommodative and functional orthoses for the feet
of ten healthy women. Two foam box techniques were
used: A) accommodative full weight bearing method;
B) functional semi-weight bearing subtalar joint
neutral-position method. Also two suspension plaster
casting techniques were used: C) accommodative
casting; D) functional subtalar joint neutral position
(Root) method. Their effect on contact area, plantar
pressure and walking convenience was evaluated on a
treadmill in standard shoes with the Novel Pedar
Insole-system®. For each orthosis 45 steps were used
to estimate contact area and peak pressures. Walking
convenience was scored on a ten-point scale.
Walking convenience in the shoe was better
rated than with orthoses (p ≤ 0.05). There were no
differences in appreciation of walking convenience
between orthoses A, B and C (p ≥ 0.20). Orthoses D
had the lowest appreciation (p ≤ 0.004).
CONCLUSIONS
The four casting methods resulted in differences
between orthoses with respect to contact areas but
only slight differences in peak pressures. In
comparison with plaster casting, foam box techniques
lead to accommodative and functional orthoses with
similar plantar pressure patterns and better walking
convenience.
RESULTS
Compared to shoes without orthosis, all orthoses
increased the total contact area, mean: 21.5 cm2
(17.4%). The mean increase in the medial mid foot
region was 12,9 cm2. Differences in contact areas
between orthoses, for total plantar surface and medial
mid foot, were statistically significant (p ≤ .015),
except between orthoses A-B and A-C (p ≥ .057).
Peak pressures for the total plantar surface with
orthoses were lower than without orthoses, mean: -7,3
N/cm2 (22.8%). Among orthoses, only the difference
between orthoses A and B was statistically significant
(p = .008). Differences between orthoses for the fore
foot were small (≤ 1,0 N/cm2) and none of them were
statistically significant (p ≥ .083): figure 1. All
orthoses increased peak pressures in the toe regions.
All orthoses produced shorter gait lines
compared to the shoe without insole (figure 2). The
gait lines of the shoe without insole and
accommodative orthoses are more medially located
compared to functional orthoses.
Figure 1: Peak pressure curve for metatarsal 3 region.
Figure 2: Gait lines or ‘centre of pressure’ paths.
PLANTAR PRESSURES AND FOOT GEOMETRY IN ATHLETES
OF DIFFERENT ETHNIICITY
Uwe G. Kersting(1), Jason Gurney (1), Dieter Rosenbaum(2)
1. Biomechanics Lab, Dept. of Sport & Exercise Science, University of Auckland, New Zealand
2. Movement Analysis Lab, Orthopaedic Dept., University Hospital Münster, Germany
INTRODUCTION
METHODS
Twenty-nine male elite Rugby League players
participated in this study. Their average age, body
height and body mass index were 22.0 +/- 2.8 y, 182.3
+/- 5.7 cm, 29.9 +/- 2.3 kg/m2 respectively (mean +/standard deviation).
Subjects had to walk across a pressure
distribution platform (EMED AT, 2 sensors/cm2,
novel GmbH, Munich) at self-selected walking speed.
Five steps for each foot were recorded. Pressure
distribution data was analyzed using Multimask
software (novel, Munich) applying the PRC standard
mask extracting data for 11 areas of interest (total foot,
medial and lateral heel, medial and lateral midfoot,
metatarsal head 1, 2, 3-5 and the according toe areas).
Foot form measures were taken from the pressure
measurements using the novel foot geometry software
(novel, Munich). Group comparisons were carried out
using a one factor ANOVA with applying a nonparametric Wilcoxon test to verify significant
differences between groups.
The three subgroups did not show any significant
differences in age, body height, bodyweight related
parameters or foot length. Foot geometry values did
only demonstrate marginal differences between groups
which were not significant (Figure 1).
Foot Shape Index
0.35
0.3
Index []
0.25
0.2
0.15
0.1
0.05
0
T
E
M
P
Group
Figure 1: Foot shape index for the total (T) sample
and the three subgroups. No significant differences
were observed.
In Figure 2 peak pressures for the metatarsal areas are presented for the total sample and the three subgroups. Significantly higher peak pressures are shown
for Pacific Islanders when compared to Europeans.
Peak Pressures
1000
*
800
PP [kPa]
It is generally believed that foot types vary with
ethnicity (Hawes, 1994). Differences might have
genetic (Chapman et al., 2000) or environmental
causes. Quantitative information on the influence of
ethnicity on dynamic foot function is limited. Veves et
al. (1995) have identified differences in foot mobility
and plantar pressure distribution in black and white
American diabetic populations. Their results indicate
differences in dynamic foot function may be an
important consideration in clinical populations. To
identify the effects ethnicity might have on foot
function the comparison of samples from similar
backgrounds needs to be carried out.
The purpose of this study was to compare
different ethnicities i.e. European (E), Maori (M) and
Pacific Islanders (P) with regard to their foot geometry
and dynamic pressure distribution parameters.
M1
600
M2
400
M345
200
0
T
E
M
P
Group
Figure 2: Peak pressures for the metatarsal areas.
Group P demonstrated significantly higher pressures
(p<0.05) in the lateral forefoot as compared to group
E.
The present data did not reveal variations in foot
geometry for comparable samples from different
ethnicities. However, dynamic pressures did vary
between groups. Results were obtained from a
relatively small population. An extension of the
database will allow to identify ethnicity-based
differences in dynamic foot function.
REFERENCES
Chapman, C et al. J Med Genet, 37(9):680-683 2000.
Hawes, MR et al. Ergonomics, 37: 187-196, 1994.
Veves, A et al. Diabet Med, 12:585-589, 1995.
TEMPORAL CHARACTERISTIC OF FOOT ROLLOVER DURING BAREFOOT
JOGGING: REFERENCE DATA FOR YOUNG ADULTS
Anneleen De Cock (1), Dirk De Clercq (1), Tine Willems (2) and Erik Witvrouw (2)
1. Department of Movement and Sport Sciences, University of Ghent, Belgium
2. Department of Rehabilitation Sciences and Physiotherapy, University of Ghent, Belgium
INTRODUCTION
Foot-to-ground contact during stance phase
in locomotion is still difficult to analyse, especially
when the foot is regarded as a multi-segmental
structure. Plantar pressure measurements are very well
suited to quantify the interaction between the different
parts of the foot and the ground and a temporal
characterization is a first step for a general picture of
foot roll over.
METHODS
Plantar pressure data were collected from
220 healthy students. A footscan pressure plate
(RsScan International, 2m x 0.4m x 0.02m, 16.384
sensors, dynamic calibration with AMTI force plate)
was mounted in the middle of a 16.5m long running
track. The subjects ran at a speed of 3.3m/s (+/0.17m/s). According to the findings of SC Wearing et
al (1999) three valid stance phases were measured for
each side. For each trial, eight important anatomical
areas (medial en lateral heel, metatarsal I-V and the
hallux) were identified on the footprint. Besides total
contact time, initial contact, time to peak pressure and
final contact for the eight areas were calculated. A
subdivision of total contact time was made into four
phases: initial contact phase (ICP), forefoot contact
phase (FFCP), foot flat phase (FFP) and forefoot push
off phase (FFPOP). Intraclass correlation coefficients
(ICC) were calculated to investigate the reliability.
Effect of gender and asymmetry were investigated
with repeated measures ANOVA and an estimation of
size effect was made by calculating a squared partial
eta (ηp²) for each significant effect.
RESULTS
The temporal pressure variables were found to
be reliable (with ICC between 0.60 and 0.90) and
gender influence and asymmetry could be neglected
on group level. Duration of the four defined phases of
total contact time are given in figure 1.
DISCUSSION
First impact, indicated by time to peak
pressures underneath the heel areas, takes place during
ICP. Afterwards forefoot contact occurs in a lateralmedial way, indicating a fast initial pronation during
FFCP. The foot becomes flat and at the end of FFP the
lateral heel area followed by the medial heel area
leaves the ground at 44.9%, which is comparable to
the time of maximal pronation. This is followed by a
resupination during FFPOP, with peak pressure
occurring underneath the lateral part of the foot. This
resupination is necessary to make a rigid and
propulsive structure of the foot for push off. Later in
the FFPOP, a more central push off pattern, first M4,
M3 and M1 and at last over M2 occurs with a final
push off over the hallux.
ICP
FFCP
FFP
FFPOP
8.2%
11.3%
25.3%
55.1%
(±4.6)
(± 5.4)
(± 9.6)
(± 7.3)
Figure 1: Mean (± standarddeviation) timing of
important phases relative to total foot contact
(0.220ms ± 0.019ms).
CONCLUSIONS
The aim of the study was to establish a
reference data set on the temporal characteristics of
foot rollover during jogging. Four functional phases
were proposed and were indirectly coupled to foot
movements. However, it is obvious that plantar
pressure measurements should be combined with other
biomechanical evaluation tools to provide a more
complete functional picture of the foot unroll.
REFERENCES
Wearing S.C. et al. Gait & posture10: 255-263, 1999
RELATIONSHIP BETWEEN GAIT BIOMECHANICS AND EXERCISE-INDUCED
LOWER LEG PAIN: A PROSPECTIVE STUDY ON RISK FACTORS.
T.M. Willems (1), E. Witvrouw (1), A. De Cock (2), D. De Clercq (2)
1. Department of Rehabilitation Sciences and Physiotherapy, Ghent University, Belgium
2. Department of Movement and Sport Sciences, Ghent University, Belgium
ABSTRACT
Exercise-induced lower leg pain is a common
and enigmatic overuse problem in athletes and
military populations (Beck, 1998). Especially runners,
track athletes and athletes participating in jumping
sports as basketball, volleyball and dancing are
diagnosed with exercise-induced lower leg pain.
Retrospective studies have noted excessive
dynamic foot pronation in subjects with a history of
exercise-induced lower leg pain (Viitisalo 1983;
Messier, 1988). In addition, static foot posture in
subjects with exercise-induced lower leg pain also
showed pronated foot alignment (Sommer, 1995).
However, one of the problems of retrospective
investigations is that of determining whether the
mechanics are a result or a cause of the subject’s
injury. Cross-sectional studies only allow clinicians to
establish relationships. Only longitudinal prospective
studies can determine cause. However, in literature,
we could not find any prospective cohort studies
which have established biomechanical intrinsic risk
factors of exercise-induced lower leg pain.
Therefore, the purpose of the current study was
to prospectively determine risk factors for exerciseinduced lower leg pain in order to increase knowledge
of the aetiology.
Subjects were 400 healthy undergraduate
physical education students. Lower leg alignment as
plantar-dorsiflexion range of motion, inversioneversion range of motion, position of the calcaneus
and flexion-extension range of motion at the first
metatarsophalangeal joint, was determined. 3Dkinematics combined with plantar pressure profiles
were collected during barefoot running at a speed of
3.33m/s. Video data were collected at 240 Hz using 7
infrared cameras (Proreflex) and Qualisys software.
For plantar pressure data a footscan pressure plate
(RsScan, 2m x 0.4m, 16384 sensors, 480 Hz, dynamic
calibration with AMTI) was used. After evaluation, all
sports injuries were registered by the same sports
physician during a certain period. During this period,
46 of the subjects developed exercise-induced lower
leg pain, of whom 29 subjects had bilateral
complaints. So 75 symptomatic lower legs, 35 left and
40 right were classified into the exercise-induced
lower leg pain group. As control group, bilateral feet
of 167 subjects who had no injuries at the lower
extremities were selected.
Cox regression analysis revealed that the gait of
subjects who will develop exercise-induced lower leg
pain has typical characteristics of a central heel
contact at first foot contact. In addition, at forefoot flat
and heel off, these subjects show a foot type, which is
more pronated and accompanied with more pressure
underneath the medial side of the foot. Resupination is
increased and the roll off does not happen across the
hallux, but more laterally, probably because of the
diminished support at the first metatarsophalangeal
joint.
The findings of this study suggest that effective
prevention and rehabilitation of exercise-induced
lower leg pain should include attention for gait
patterns and adjustments of foot biomechanics.
REFERENCES
Beck, Sports Med 26:265-279,1998.
Messier et al, Med Sci Sports Exerc 20:501-505,1988.
Sommer et al, Med Sci Sports Exerc 27:800-804,1995.
Viitasalo et al, Am J Sports Med 11:125-130,1983.
CHANGES IN PLANTAR SURFACE AREA UNDER
DIFFERENT LOADING CONDITIONS
Bill Vicenzino (1), Thomas G. McPoil (2), Mark W. Cornwall (2)
1. Sport Physiotherapy Program, University of Queensland, Brisbane, Australia
2. Gait Research Laboratory, Northern Arizona University, Flagstaff, Arizona, USA
INTRODUCTION
Previous research has been vague regarding the
importance of the amount of plantar surface area in
contact with the supporting surface with regard to the
development of foot pathology. Giladi et al (1985)
and Cowan et al (1993) have reported that low arches
are associated with a lower risk of overuse injury,
including stress fractures. Kaufman et al (1999),
however, have noted that low arches increase the risk
of stress fracture. Furthermore, Yen et al (1998) have
stated that high arches are more protective against
overuse injuries. Because of the ambiguity, it would
appear to be prudent to obtain plantar surface area data
when performing pre-season screening for athletes
involved with sports that require high levels of
endurance training. While the typical method to
obtain a footprint to obtain plantar surface area is
through the use of an imprinting system, this method
is messy and time-consuming. The use of a plantar
pressure system to obtain plantar surface area would
not only decrease the time required for footprint
collection but also reduce the time required for data
analysis. Thus, the purpose of this study was to
determine the change in plantar surface area with three
different loading conditions using the EMED pressure
platform for data collection.
The mean stance phase duration for walking was
.623 sec and the ICC (2,1) was .96. The mean support
phase for running was .308 sec and the ICC (2,1) was
.97. Descriptive statistics are presented in Table 1.
METHODS
Twenty volunteers, 5 men and 15 women, with
no history of lower extremity congenital or traumatic
deformity, or acute injury 6 months prior to the start of
the study consented to participate. The subject mean
age was 28.8 years (range of 23 to 53 years). Subjects
selected had at least a 10mm change in navicular drop
for at least one foot. Pressure data were collected as
each subject stood with 50% body weight on each foot
as well as while walking and running over a 12-meter
runway with the EMED platform positioned at the
midpoint. Subjects were allowed to use a self-selected
walking and running speed, which was monitored to
ensure consistency among all recorded trials. Pressure
data were collected over a 1-minute period for static
standing and five times for each foot while each
subject was walking and running.
Novel Percent
Mask and Multimask software was used to determine
the Arch Index (AI), as previously described by
Cavanagh (1987), for all trials.
(in cm2)
Mean
Std. Dev.
Std. Error
.087
.092
.014
Static AI
.205
.067
.011
Walk AI
.268
.056
.009
Run AI
Table 1: Descriptive statistics for Arch Index.
The result of the ANOVA on AI was significant
(p<.0001) among standing, walking and running, but
not significant (p>.05) for differences between
extremities. The post-hoc analyses indicated that AI
was significantly different among all three different
loading conditions.
The correlation coefficient
between walking AI and running AI was .89.
Correlation coefficients between standing AI versus
walking AI and running AI were .634 and .635
respectively. The results indicate that while the
walking AI obtained from a pressure platform is
highly predictive of the same subject’s running AI, the
static AI is a poor predictor of both the walking and
running AI. While previous research has reported
similar correlations for AI between walking and
running, correlations between static standing were
more predictive of both walking and running than in
the current study. This result could be due to the fact
that the traditional method of using an inked mat for
obtaining a footprint may be more sensitive to the
plantar surface area while standing with a load of 50%
body weight than a pressure platform.
SUMMARY
The use of a pressure platform to obtain plantar
surface area data is more time-efficient and permits
more rapid data reduction. Based on the results of this
study, plantar surface data would only be collected
while walking, and not in static standing, to predict
running.
REFERENCES
Giladi et al, Orthop Rev 14:709-712, 1985.
Cowan, et al, Arch Fam Med 2:773-777, 1993.
Kaufman, et al, Am J Sports Med 27:585-593, 1999.
Yen, et al, Clin J Sports Med 8:187-194, 1998.
APPLICATION OF CENTRE OF PRESSURE TO INDICATE REARFOOT
INVERSION-EVERSION IN A SIMULATED SHOE SHOP SETTING
Sharon J. Dixon
School of Sport and Health Sciences, University of Exeter, Exeter, EX1 2LU, UK.
INTRODUCTION
METHODS
Pressure plate and movement data were recorded
for right and left sides for 16 rearfoot strikers. For
each subject, pressure data were collected for one
representative step for each foot while running at their
preferred running speed, as would typically occur in a
running store. The centre of pressure pathway was
characterised using deviation from a straight line from
the heel through the second metatarsal, with negative
values indicating a lateral location. Deviation from
this line (x) during the initial ground contact phase
was used to represent centre of pressure range of
motion (Figure 1).
In addition to the collection of pressure data,
rearfoot range of motion (ROM) was monitored
during the period from initial ground contact to peak
eversion using a Peak realtime system sampling at 120
Hz. Movement data were collected for five running
trials for each side of the body, with running speed
monitored to ensure comparable speed to that obtained
during the pressure data collection (±5%). The
relationship between rearfoot movement and centre of
pressure deviation was investigated by calculation of a
correlation coefficient. Subjects were also grouped as
having ‘high’, ‘medium’ or ‘low’ range of motion of
rearfoot movement, using the bottom 25%, middle
0
-5
COP_x (mm)
Pressure plates are increasingly used as a tool to
help in the choice of appropriate footwear for runners.
A typical procedure involves the collection of pressure
patterns for barefoot running and the use of these data
to categorise runners as ‘high’, ‘normal’ or ‘low’
pronators. Despite several investigations into possible
relationships between pressure data and rearfoot
eversion, strong evidence relating specific aspects of
pressure data to rearfoot movement is lacking (Dixon
and Turrell, 2001).
The aim of the present study was to investigate
whether quantitative analysis of centre of pressure
time history using pressure plate data obtained for
shod running revealed any relationship with the
amount of rearfoot eversion. It was hypothesised that
subjects exhibiting high total rearfoot movement
during the initial ground contact phase would also
show a large lateral-medial deviation of the centre of
pressure.
0
0.05
0.1
0.15
0.2
0.25
-10
-15
-20
-25
Centre of
pressure
ROM
-30
-35
time (s)
50% and top 25%. An ANOVA was used to test
whether there were significant differences in centre of
pressure ROM between these groups (p<0.05).
Figure 1: Typical centre of pressure latera-medial
deviation, indicating ‘x’ range of motion (ROM).
A significant correlation was identified between
the amount of rearfoot movement and centre of
pressure deviation (R=0.46, p<0.05). The comparison
of runners with ‘high’ (20.4±3.5º) and ‘low’ (9.9±0.8º)
total rearfoot movement revealed a significantly
greater amount of lateral-medial centre of pressure
deviation for the high pronators (20.4±8.7 mm,
compared with 15.0±2.7 mm).
Although the relatively low correlation
coefficient of 0.46 does not support the use of pressure
data alone to predict the amount of rearfoot inversioneversion movement, the difference detected between
high and low pronators provides support for the study
hypothesis. It is therefore suggested that centre of
pressure deviation has potential to differentiate
between those classified as high or low pronators,
providing a useful tool for the identification of runners
requiring specific footwear.
REFERENCES
Dixon and Turrell, J Sports Sci 20: , 2001.
CLINICAL PROFICIENCY OF DUTCH PODIATRISTS, PEDORTHISTS AND ORTHOTISTS
REGARDING PLANTAR PRESSURE REDUCTION
Nick Guldemond (1a), Pieter Leffers (2), Antal Sanders (1b), Nicolaas Schaper (1c), Geert
Walenkamp (1a)
1. a) Orthopaedic Surgery, b) Rehabilitation Medicine, c) Internal Medicine. University Hospital
Maastricht, The Netherlands University Hospital Maastricht, The Netherlands
2. Fac. Medicine, Dept. Epidemiology, Maastricht University, The Netherlands
BACKGROUND
There is limited information about differences
between disciplines regarding orthoses therapy.
Plantar pressure relief is a common treatment goal.
The first aim of this study was to evaluate the ability
of clinicians to identify locations with high bare foot
peak pressures (PP) and the competence to reduce
inshoe PP’s with foot orthoses.
METHODS
Ten podiatrists (Pod), 10 pedorthists (Ped) and
11 orthotists (Ort) participated. Three patients
(A,B,C) with fore foot complaints indicated for foot
orthoses were examined by each clinician. Presumed
high PP regions could be marked through hatching an
illustration of a plantar aspect. The marked regions
were related to the location of the actual bare foot PP’s
measured with the Novel EMED SF-4® pressure
platform. Regression analysis was performed to assess
the relation between the percentage of markings per
discipline and the PP’s for 6 fore foot regions.
Totally, 186 orthoses were made. The effect of
the orthoses on PP’s was evaluated on a treadmill in
the patient’s own shoes with the Novel Pedar Insolesystem®. For each orthosis 30 steps were used to
estimate PP’s.
RESULTS
The regression coefficients (b) showed positive
and negative relationships between clinical methods of
high PP identification and quantitative PP
measurement (example fig. 1). One would expect
positive relations, since higher PP’s should result in a
higher percentage of markings. All b’s were not
statistically significant (p ≥.155). All adjusted
coefficients of determination (Adj. r2) were below
0.30 and most were smaller than 0.20 (table 1).
PP’s in the shoes with orthoses of both Ort and
Ped where significantly decreased compared to
orthoses of Pod for all patients, except for C left (p ≤
0.01): table 2. Regarding the right foot of A, orthoses
of Pod resulted in an increase of PP. There was no
statistically significant difference in PP’s between Ort
and Ped for any patient (p ≥ 0.14). For the left foot C
there was no statistically significant difference in PP’s
between all groups (p ≥ 0.22).
CONCLUSIONS
Orthoses of Ped and Ort achieved a greater peak
pressure reduction in the fore foot regions than
orthoses of Pod. The ability to distinguish between
locations with high and low PP’s through use of
traditional clinical methods is poor. This points
towards the merit of quantitative PP measurement for
clinical practice.
Figure 1: % of markings per discipline and PP’s for 6 regions
Pod
Ped
Ort
b
Adj. r2
b
Adj. r2
b
Adj. r2
Foot
A left
0.47
0.16
0.68
0.23
0.15
0.03
A right
-0.91 0.05
-1.62
0.04
-0.85 0.16
B left
0.96
0.29
0.73
0.01
0.07
0.14
B right
0.49
0.05
-0.26
0.23
0.01
0.25
C left
0.25
0.03
0.11
0.20
-0.28 0.03
C right
-0.44 0.11
0.10
0.24
0.43
0.05
Table 1: regression coefficients & adjusted coefficients of
determination
Pod
Ped
Ort
Md ∆ (±SD)
Md ∆ (±SD)
Md ∆ (±SD)
Foot
A left
-0.6 (±4,5)
-7.0 (±4,5)
-8.7 (±5,0)
A right
6.2 (±5,4)
-4.7 (±5,5)
-5.0 (±2,6)
B left
-0.6 (±2,7)
-6.3 (±2,7)
-6.0 (±3,6)
B right
-2.2 (±4,1)
-7.6 (±3,0)
-5.2 (±3,1)
C left
-15.1 (±3,7)
-12.2 (±6,0)
-16.5 (±6,6)
C right
-4.4 (±2,5)
-6.8 (±2,3)
-4.7 (±3,9)
Table 2: median (Md) PP reduction & standard deviations (SD).
VALIDITY OF THE PEDAR MOBILE SYSTEM OF VERTICAL FORCE
MEASUREMENT DURING A LONG-TERM PERIOD.
Henri. L.P. Hurkmans (1), Johannes. B.J. Bussmann (2), Ruud. W. Selles (2),
Herwin. L.D. Horemans (2), Eric. Benda (1), Henk. J. Stam (2), Jan. A.N. Verhaar (3)
1. Department of Physical Therapy
2. Department of Rehabilitation Medicine
3. Department of Orthopedic Surgery
Erasmus MC - University Medical Center Rotterdam, The Netherlands
200
BACKGROUND
s1
s2
150
s3
s4
s5
100
Force (N)
Objective measurement of weight bearing during
a long-term period is essential to gain insight in the
postoperative loading of the lower extremity of
orthopedic patients to avoid complications (Perren and
Matter, 1996; Siebert, 1994; Wirtz, 1998). This study
investigated the validity of measuring the vertical
force using the Pedar Mobile insole pressure system
during a long-term period by comparison with a
Kistler force plate. In addition, the validity of a new
sensor drift correction program (SeDriC) developed to
correct for offset drift in the Pedar signal, was
evaluated.
50
0
1
2
3
4
5
6
7
-50
Time (hours)
METHODS
Dynamic and static force data during loading and
unloading conditions were collected from 5 healthy
subjects every hour for 7 hours with the Pedar Mobile
system (PMS) and a Kistler force plate.
RESULTS
A mean offset drift of 14% was found after 7 h.
After applying the SeDriC program the Pedar system
showed a high accuracy for the second peak force (1.1
- 3.4% difference, p > 0.05) and step duration (-2.0 4.4% difference, p > 0.05). Less accuracy was found
for the first peak force (5 - 12% difference; p < 0.05
for the first three hours, p > 0.05 for the last four
hours), and consequently the linear impulse (5.5 - 11%
difference, p > 0.05).
CONCLUSION
Considerable offset drift was found after 7 h.
The Pedar Mobile system appeared to be a valid
instrument to measure the vertical force during a longterm period when using the developed drift correction
program described in this study.
REFERENCES
Perren and Matter, Swiss Surgery 2:252-258, 1996.
Siebert, Hip International 4: 61-68, 1994.
Wirtz et al, Z Orthop Ihre Grenzgeb 136: 310-316,
1998.
Figure 1: The absolute drift of Pedar force data for
the five subjects over 7 h, measured by the PMS
during swing phase of the dynamic measurements.
(A)
1000
F1
F2
Fy
Pedar
(N)
800
600
400
200
0
0
0.5
1
1.5
2
2.5
3
3.5
0
0.5
1
1.5
2
2.5
3
3.5
0
0.5
1
1.5
2
2.5
3
3.5
(B)
(N)
1000
Fy
Pedar corrected
800
600
400
200
0
(C)
1000
Fy
Kistler
(N)
800
600
400
200
0
Time (s)
Figure 2: Offset drift correction using SeDriC.
A: Pedar data before drift correction of the first 3
right steps of subject 2, at hr 1 ( ▬ ) and hr 7 ( ― ).
B: The same Pedar data after drift correction.
C: Kistler data of the third right footstep.
F1 = 1st peak force; F2 = 2nd peak force.
EVALUATION OF A CAPACITIVE PRESSURE SENSOR FOR JOINT CONTACT
STRESS MEASUREMENTS
Lorenzo Martinelli (1,2), Dieter Rosenbaum (1), Tommaso D'Alessio (2)
1.
2.
Movement Analysis Lab, Orthopaedic Department, University Hospital Münster, Germany.
Applied Electronic Engineering Department, University "Roma 3" Roma, Italy.
INTRODUCTION
Until nowadays various in vitro methods have
been developed in order to understand the mechanics
of articular joints, but none completely satisfies the
task. Capacitive mats have been used in a wide range
of applications, e.g. for knee joint loading analysis.
Due to the lack of knowledge of force and contact area
models of the ankle joint, a prototype sensor was
designed by Novel GmbH.
This study investigated the properties of the
capacitive sensor during different test procedures
simulating ankle stress patterns.
The AJP (Ankle Joint Pressensor) system
includes a capacitive sensor, PEDAR computer
interface and Pliance m-Expert software (v. 10.1.4).
The sensor is 1 mm thick, composed of 194 cells
2.5*2.5 mm, the sensitive area is 2.8*4.3 cm and 50
Hz is the maximum sampling frequency. It can detect
pressures in a range from 4.5 up to 250 N/cm2. The
test was carried out using a Zwick 005 material test
machine and custom loading surfaces (flat, cylindrical
& spherical; Fig. 1).
• Known forces were applied with 25 repetitions. The
cycle frequency was 1 Hz, 0.25 Hz and 0.1 Hz.
Both flat and spherical surfaces were used.
• Two spheres with 3 cm and 5 cm radius were used
to detect crinkling artefacts.
• Creep and hysteresis artefacts were investigated
respectively by applying a known force for five
minutes and running a cycle through three steps:
50 N, 100 N and 150 N. The cycle frequency was
0.25 Hz.
RESULTS
Due to the finite sensor resolution, the error in
the contact area detection was depending on the shape
of the surface applied. For the indentor B the error was
20% while for A it was 16%. Applying two semicircles (total area 3.3 cm2) the error dropped to 10%.
The error in force detection for a single loading cycle
was under 2%.
The force error in 25 cycles was under the 2%
for each load in all force ranges. The error did not
depend on the kind of surface used. The sensor did not
show a “memory effect” during cyclic loading.
The AJP did not appear to be affected by
crinkling artefacts, even if in the 3 cm radius plates the
force error increased to 15%.
Creep manifested in an overestimation of the
applied load of about 15% after 300 sec. The sensor
manifested hysteresis after the 8th cycle.
DISCUSSION
Figure 1: System set-up with spherical and cylindrical
indentors.
In order to investigate the AJP behaviour, the
following tests were carried out:
• Three loads, 50 N, 100 N, 150 N, were applied
using cylindrical indentors (A: 3.3 cm2, B: 0.9 cm2)
in different load configurations. Force and contact
area were recorded and errors were calculated.
The test validated the low error in force detection
of the AJP. Post-acquisition analysis showed that
contact area error could be significantly reduced using
masks during data acquisition. The new value range
was under the 10%. Creep artefact could be reduced
according to the procedure described by Arndt, 2003.
Due to the softness of the dielectric material the sensor
appears more suitable for stress detection within
irregular surfaces as joints. Further research is
required for compatibility analysis with ankle joint
prosthesis.
REFERENCES
A. Arndt, J Biomech 36:1813-1817, 2003.
PUBLICITY OF PRESSURE DISTRIBUTION (NOVEL).
Dr. Iveta Spodrina (1), Prof. Marcis Krumins (2), Dr. Med. Aivars Vetra (3)
1. Center of Prosthetics and Orthopaedics, Latvia
2. Riga Stradins University, Latvia
INTRODUCTION
In professional literature we can read articles and
reserches which are made about pressure distribution
methods – indications and aplications.We didn`t find
any facts or analysis about spetialists who send
patients to this investigation method.
MATERIAL AND METHODS.
To clear up we made a spetial inquiry which
helped us to find out how patints know about this
method ( we work with NOVEL emed adnd pedar
from the February of 2003 till the February of 2004 ),
and why they need special investigation. The range of
reasons and spectrum of problems were different. We
had 311 respondents which were investigated by emed
and pedar systems.
RESULTS
During 11 months 311 patients were investigated by
emed and pedar systems. 60 of them were sent by
traumatologists- podiatrists, 52 – by family doctors, 4
– by endocrinologists, 55 – by themselves( receiving
information from radio, professional articles, press ),
51 – by acquaintanceships( who were our patints
before ), 50 – time after time, 39-by trainers. We
evaluate the answers to our inquiary – where patients
receive the information about NOVEL systems and
how seriuos the information was. The point system
was used. 3 points – patient knows very well about the
system and why it mis necessary for him; 2 points –
knows something about pressure measuring, but truly
doesn`t know how it works; 1point – doesn`t know
nothing – only has specialists order. The main
problems were 44% - foot deformities, diabetic foot –
28%, congenital deformities – 15%, rheumatic
deformities 10%, others – 3%.
CONCLUSIN
The indices are very similar ( exepting
endocrinologists ).Mostly these methods are known by
doctors whose patients have “ foot problems “ and
patients with foot and walking problems. The
information about NOVEL system is notmisatisfactory
in Latvia. At last months the quantity of patients has
tendency to growing. We must inform the family
doctors ( seminars, articles )- they are alongside with
patient and must inform them about indications for
emed and pedar systems ( in our case sending utility
was 76% ).

emed scientific meeting 2004 - emed scientific meeting 2006

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