What is Hip dysplasia?
This is a condition where there is abnormal development of the hip joint. There is a genetic component to the condition but a puppy is born with normal hips and the abnormalities develop as the dog gets older. The condition leads to joint laxity (slackening of the soft tissues around the joint). The laxity can develop as early as 7 weeks of age. As the hip joint is a ball and socket joint, the two sides of the joint do not fit together properly (incongruent) and this leads to abnormal shaping of the joint. The ball flattens and the socket widens to become saucer-like. Secondary osteoarthritis develops as a result of this condition. The condition frequently affects both hips at the same time.
What causes hip dysplasia?
This condition has genetic (multiple genes are involved) and environmental components. The genetics are determined by the parents whereas environmental factors relate to anything other than the patient’s DNA, such as body condition, diet, etc. A patient will only develop hip dysplasia if it has the genetic programming. Environmental factors alone will not cause this condition.
What are the signs of hip dysplasia?
The most common sign is limping in the back legs. One or both legs may be affected. The signs can be very varied with some patients appear worse after rest and struggle to rise, whereas others may be lame during a walk. Some patients have a reduced tolerance to exercise and others have a swaying hind limb gait (wiggly bottom). This condition is seen predominantly in dogs but can also be diagnosed in cats. Many patients will present at 6-12 months of age. Older dogs can also present if the osteoarthritis is becoming debilitating. This condition may be present in some dogs and they show no obvious clinical signs. Hip dysplasia can be uncomfortable with young dogs showing pain due to stretching of the joint soft tissues which contain nerve fibres. Older dogs can show discomfort due to loss of cartilage in the joint.
We may become suspicious of this condition when certain clinical signs are seen such as lameness, stiffness after rest, an inability to jump etc. The definitive diagnosis is made when a combination of clinical examination, assessment under sedation / anaesthesia and radiography (x-ray) is performed.
Radiography can document the presence of hip dysplasia but correct positioning is required. Assessing a patient which is under sedation or anaesthesia also allows the surgeon to detect any laxity in the joint during hip manipulation.
Hip dysplasia treatment
Treatment is based on a patient’s clinical signs and severity of condition. Not all treatment options are appropriate for all animals and so it is our surgeons’ job to discuss with you the most appropriate treatment option for your pet.
Non-surgical / conservative management
If the clinical signs are mild or if the condition has been diagnosed incidentally, then this may be the most suitable option. The mainstay of this treatment is body weight control, exercise control and standardisation, physical therapy, anti-inflammatory pain killers and dietary supplements. With this management, we would hope for a long term improvement so if the positive results are only transient, other options may need to be discussed.
There are two types of surgical treatments. Procedures that alter the anatomy of the hip and others that save the limb but remove the hip joint, so called salvage procedures.
Anatomy altering surgery