xray2000

Pattern recognition of the
shoulder
By Florence Davidson
SORSA-RSSA 2013
Contents
• A method and terminology used for pattern
recognition of the appendicular skeleton
• Overview normal anatomy: shoulder
• Common projections for trauma
• Interactive clicker session: shoulder & cervical
spine
Cardinal rules
• Correct patient (identity and anatomy)
• Sufficient diagnostic quality (anatomy demonstrated,
exposure, whether repeat or supplementary views
needed)
• Radiographer comments must only be made on visible
radiographic appearances- if the medial end of the
clavicle is omitted from an AP shoulder projection, it is
impossible to comment on the normality of the SC
joint.
• All images relating to the examination must be viewed
(Snaith: 2005)
Pattern recognition of the skeleton:
1. Bones
Trace around the cortex (edge) of every bone
The bony outline should be smooth (any
breaks in the presence of trauma= a fracture)
Check the trabecular pattern which should
have a smooth and regular appearance- look
for any black (lucent) or white (sclerotic) lines
which may indicate separation or overlapping
of bone fragments.
Pattern recognition of the skeleton:
2. Joints
• Look carefully at all the components of a joint
for alignment of the articular surfaces, in
particular the edge of joints.
Pattern recognition of the skeleton:
3. Soft tissues
• Check for any evidence of soft tissue swelling,
disruption of fat planes or presence of any
foreign material. Sometimes soft tissue
changes may be the only clue to subtle injury.
(Snaith: 2005)
Review approach
Review approach
Features
Anatomy and laterality
Identify abnormality
Describe fracture type
Intra/extra-articular
Position
Displacement/angulation-direction
Once you have the elements above, assemble in a succinct way
(Snaith: 2005)
Paediatric fractures
• Many variations
• Differ from adults due to elasticity of
children’s bones
• Radius and ulna most commonly injured with
buckle (Torus #)
• When # involves epiphyseal plate, Salter
Harris classification is used
• Sufficient for radiographers to ID # as
metaphyseal or epiphyseal
Some “terms”:
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Cortical bone (cortex)
Periosteum
Trabeculae
Mineralisation
Intra, extra and periarticular
Fat pad
Lucent
Sclerotic
Anatomy of the shoulder
• The glenohumearal joint has a great range of motion.
• The glenoid fossa is small and the joint capsule is lax making it
prone to subluxation and dislocation.
Robin Smithuis and Henk Jan van der Woude
Anterior view
Posterior view
Normal appearance
• AP
• Humeral head not
symmetrical
• Looks like the head of a
walking stick
• The articular surfaces of the
humerus and the glenoid
parallel to each other.
Raby et al: 1995
Normal AC JOINT:
3-5mm (up to
7mm)
Normal shoulder: internal rotation
Normal shoulder: external
rotation
Figure 4.3.
The Y view.
The humeral
head
overlies the
centre of the
glenoid (G).
The Y is
formed by
the j junction
of the
scapular
\ blade,
coracoid (C)
and
acromion
(A).
Raby et al:
1995
Raby et al: 1995
http://www.wikiradiography.com/page/I
maging+Shoulder+Dislocations?t=anon
Shoulder pathologies
• Dislocations: Anterior most common
• Subluxations: AC joint
• Fractures: Clavicle # most common in children,
scapula # are rare, elderly commonly #
proximal humerus
• Soft tissue: calcification of tendons
Dislocations: Anterior (most common)
http://www.wikiradiography.com
http://www.wikiradiography.com
Dislocations: Posterior (only 5%)
Raby et
al:1995
Figure 4.19. Posterior dislocation. Y view. The!
humeral head lies behind the glenoid (the centra of
the Y).
http://www.wikiradiography.com/photo/8178
625/poaterior+shoulder+dislocation
http://image.wikifoundry.com/image/1/KikuxU
0zw9CTWoMCXU5HIg241164
Calcific tendonitis
Pattern recognition of the
cervical spine
Contents:
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Normal anatomy & radiographic anatomy
Fracture prevalence
Projections & pattern recognition
Soft tissue structures
Pathomechanics
Stability
Classification of trauma
Fracture prevalence
• # C5/C6 common (most injuries due to hyper
flexion)
• # infrequent in children <8yrs (likely to involve
C1/C2)
• Neurological damage occurs in about 40% of
cases (due to burst # or facet joint dislocations)
(Nunn)
• One third of injuries occur at the level of C2, and
one half of injuries occur at the level of C6 or C7.
(http://www.radiologyassistant.nl/en/p4902153514
6c5/spine-cervical-injury.html#i49021535369a6
Ligaments:
Although not demonstrated
radiographically, disruptions
are evidenced by alignment
and location of the osseous
structures supported by the
ligaments (Nunn)
McConnell et al: 2005
McConnell et al: 2005
An injury is considered unstable if 2 of
the 3 columns are disrupted
A patient with a suspected C/Spine
injury can be cleared:
http://www.radiologyassistant.nl/en/p490215
35146c5/spine-cervicalinjury.html#i49134bdbb8298
Projection: Lateral
Projections: Lateral
• Most detectable abnormalities will be visible
on lateral view.
• Trace 3 anatomical lines:
Projection: “Swimmers”
• To assess alignment of C7 with T1: “Is there
subluxation?”
Soft tissue signs
• The retropharyngeal/preveretebral soft
tissues can provide signs of cervical spine
injury.
• This image demonstrates normal
preveretebral soft tissues:
 C2 (Black arrows): The prevertebral soft
tissues at C2 should measure less than 7mm or
less than 50% of the width of the adjacent
vertebral body
 C6 (White arrows): The prevertebral soft
tissues at C6 should measure less than 22mm.
Or not be greater than the width of the
adjacent vertebral body.
These are guides only and must be interpreted
in the context of bony appearances,
mechanism of injury and clinical signs.
http://www.wikiradiography.com/page/Soft+Tissue+
Signs-+Cervical+Spine
Lateral:
• Vertebral bodies and
intervertebral discs should be
of uniform height at both the
anterior and posterior parts
(3mm difference can indicate
wedge compression fracture)
Lateral:
The normal relationship
between the anterior arch
of C1 and the odontoid
peg: not >3mm in the
adult
Raby et al
Projections: AP
• Assess superior & inferior end plates, spinous
processes, lateral masses
 SP in straight line (?bifid)
Raby
AP
Malalignment of SP?Facet joint dislocation
Raby
AP:
• Distance between SP should be equal
 Anterior cervical dislocation
Raby et al: 1995:
http://www.radiologyassistant.nl/en/p49021535146c5/spinecervical-injury.html#i49021535369a6
Projection: AP open mouth (C1/C2)
• Lateral masses of
C1 should not
overhang lateral
masses of C2
(Burst #?)
• Symmetric space
between
odontoid peg &
lateral masses of
C1 (? Rotation)
• Artefacts
mimicking #?
Jefferson fracture (burst
fracture of C1)
http://www.scientificspine.com/spinal-diseases/atlas-fracture.html
Axis (C2)
• Odontoid peg
• Hangman’s fracture
http://www.radiologyassistant.nl/en/p49021535146
c5/spine-cervical-injury.html#i49021535369a6
McConnell et al: 2005
Teardrop extension
fracture
Wedge compression
fracture
www.mdguidelines.com
Fracture spinous process
Raby et al: 1995: 106
References:
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Bontrager, K & Lampignano. 2005. Textbook of Radiographic Positioning and
Related Anatomy. St Louis: Elsevier Mosby
Mc Connell, J; Eyres, R & Nightingale, J. 2005. Interpreting Trauma Radiographs.
Oxford: Blackwell publishing
Moeller, T. 1999. Normal findings in Radiography. New York: Thieme Stuttgart
Raby, N; Berman, L 7 De Lacey, G. 1995. Accident & Emergency Radiology, A
survival guide. London: WB Saunders
Snaith, B. 2005. Radiographer comments in practice: Describing injuries. Synergy:
December
www.ceessentials.net
www.imageinterpretation.co.uk
http://www.radiologyassistant.nl/
www.radiopaedia.org
www.wikiradiography.com
www.xray2000.co.uk