Your Pet - Animal Health Trust

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Your Pet
Registered charity no: 209642
H I P DY S P L A S I A
&
Your Pet
H I P DY S P L A S I A
The Animal Health Trust is an
internationally recognised centre of
excellence in the field of veterinary
medicine.
It has pioneered many breakthroughs in
relation to improving the prevention,
diagnosis and treatment of animal disease
and injury and is entirely dedicated to
improving the health and welfare of cats,
dogs and horses.
As a registered charity we receive no
government funding and rely on
charitable support in the form of legacies
and donations to enable us to continue
our valuable work. You can help us in
the following ways:
•
•
•
•
Becoming an AHT Friend
Making a donation
Buying AHT merchandise
Remembering us in your Will
To find out more
Telephone:
Fundraising Department on 08700 502380
Email: [email protected]
Visit our website: www.aht.org.uk
Animal Health Trust
Lanwades Park
Kentford
Newmarket
Suffolk
CB8 7UU
the science behind animal welfare
Animal Health Trust
Animal Health Trust
the science behind animal welfare
DOG_NEW_HIPDYSPLASIA.qxp
3/3/05
3:16 pm
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Your Pet
H I P DY S P L A S I A
What is hip dysplasia?
The hip, or coxofemoral joint, is a ball-and-
features and partly by environmental factors
such as nutrition, bodyweight and exercise.
socket joint comprising a cup-shaped socket
Therefore, the radiograph simply records the
and the head of the thigh bone or femur, which
physical end-result of a variety of causes and, at
is roughly spherical. These are held in place by
present, this is the best tool for screening dogs
soft
the
for hip dsyplasia. Although different assessment
surrounding muscles. The term ‘hip dysplasia’ is
criteria are used in different countries,
used to describe hip joints which are loose
discussions between interested parties are on-
and/or ill-fitting, many of which will develop
going in an attempt to provide some
osteoarthritis as the dog ages. In the young
international standardisation.
tissues
and,
to
some
extent,
puppy, the skeleton is fairly soft and any laxity
radiographed by the owner’s veterinary surgeon
and the radiographs are submitted to the BVA
where each film is examined by 2 veterinary
How are hip radiographs taken?
surgeons from its panel of expert scrutineers.
Radiographs are taken when the dog is lying on
Nine anatomical parameters are examined
its back with its hind legs extended and rotated
from each hip joint and allocated a score,
inwards so that the thigh bones are parallel. The
ranging from 0 (perfect) to 6 (worst). The scoring
advantage of this position is that it can be
scheme allows dogs within a breed to be
reproduced consistently on different occasions,
compared with each other, and dogs should
although a number of other projections may be
only be used for breeding if their hip score is
continue to cause bony remodelling and the
employed
supplementary
well below the average score for that breed. It
production of arthritic new bone.
information. Sedation or general anaesthesia
is also helpful to consider the hip scores of the
How can hip dysplasia be diagnosed?
are necessary to allow accurate positioning
parents, grandparents and siblings when
Certain clinical signs such as pain on rising or
without the need for the animal to be held. The
selecting a dog or bitch for breeding. Dogs
abnormal gait can lead to a suspicion of hip
radiographs must be identified accurately with
should only be used for breeding if their hip
dsyplasia but it must be confirmed with an X-
the dog’s Kennel Club registration number, the
score is well below the average score for that
ray. However, many dogs with hip dysplasia
date and a right/left marker.
breed.
show no clinical signs until later in life, when
What is the Kennel Club Hip Dysplasia
Scoring Scheme?
Ruth Dennis
arthritis has developed. If they have been used
for breeding, hip dysplasia genes will have
In the UK an assessment scheme is run under
R.C.V.S. Recognised Specialist in Radiology
been passed to their offspring. The condition is
the joint auspices of the Kennel Club and the
European Specialist in Veterinary Diagnostic
a disease which is governed partly by genetic
British Veterinary Association (BVA). Dogs are
Imaging
or incongruity of the hip joint will result in an
abnormal
conformation.
As
the
animal
matures, this abnormality becomes permanent
as the skeleton hardens. Even following skeletal
maturity (at about one year of age) abnormal
stresses on the bones and soft tissues can
to
provide
MA VetMB DVR DipECVDI MRCVS