Dog - Hip Dysplasia

I have been told that my dog has hip dysplasia but there is no lameness. Can the diagnosis be correct?

Hip dysplasia is a deformity of the hip which occurs during growth. The hip joint is a ball and socket joint. During growth both the ball, (which is the head of the femur or thigh bone) and the acetabulum, (the socket in the pelvis), have to grow at equal rates if the joint is to function.

With hip dysplasia this does not occur. The result is laxity (loose-ness) of the joint, which is soon followed by degenerative joint disease – arthritis, the reaction of the body in an attempt to stabilise the ‘loose’ hip joint.

The degree of lameness that occurs is usually dependent on the extent of these arthritic changes and may not be directly correlated with the x-ray appearance of the hip joint. Therefore although your dog may appear to have loose joints on x-ray, at present when moving he may be completely sound. However radiograph (x-rays) indicating laxity are an indication that sooner or later arthritic change will occur.

What causes it?

Hip dysplasia is said to be multifactorial and polygenic. This in other words means that although hereditary, more than one gene is involved. Factors including weight, rate of growth, type of food, amount of exercise etc. are involved.

Since it is hereditary I presume it is more prevalent in some breeds of dogs than others?

Yes, although most breeds of dog can be affected it is predominantly seen in larger dogs. German Shepherd Dogs, St Bernards, Labradors, Labrador Retrievers and Old English Sheepdogs are among the most commonly affected breeds. However, it should be remembered that mongrels can also be affected.

What symptoms should I look for?

Weakness and pain in the hindlegs are the usual clinical signs. The dog appears wobbly behind and is reluctant to rise from a sitting position. This can be seen in puppies a few months old but is most common in dogs aged one to two years.

Dogs with mild hip dysplasia on x-ray may develop minimal arthritis often with no clinical signs until they are quite elderly.

How is it diagnosed?

A hip x-ray (radiograph) will indicate that hip dysplasia is present but there may be no clinical signs. Usually the owner of a large breed dog will seek advice because the dog has difficulty rising. Clinical examination may reveal laxity of the hip joint but definitive diagnosis will be by radiography.

What is the treatment?

This depends entirely upon the clinical signs and the amount of discomfort shown by the dog. Initially anti-inflammatory drugs will probably be prescribed. Today there are very effective non steroidal anti-inflammatory drugs, (NSAIDs) that have minimal side effects. However just as NSAIDs with people, the choice of NSAID has to be made on an individual basis and sometimes various drugs may have to be tried before the most effective one is found for your dog.

Long term treatment with these drugs again depends upon the general health status of the patient and sometimes alternative treatments will be advised.

What are these and do they work?

The alternative to pain killers and controlled exercise is surgery, although in mild cases nutraceuticals, e.g. chondroitin, glucosamine and vitamins do help.

There are several surgical procedures available. These range from a total hip replacement, similar to the operation carried out on people, to a procedure called triple osteotomy which involves the shallow socket (acetabulum) of the hip joint being surgically deepened to provide more stability.

Each case has to be assessed individually in respect to the line of treatment to be recommended.

I hoped to breed from my dog. Is this advisable?

As already mentioned the condition is known to be inherited. In some breeds it is so prevalent that it would be hard to find an individual that did not show at least some radiographic signs of hip dysplasia.

In consequence in the UK the British Veterinary Association together with the Kennel Club run a scheme known as the BVA/KC Hip Dysplasia Scheme. The hips are x-rayed in a standard position, usually with the dog either deeply sedated or lightly anaesthetised. The x-rays (radiographs) are then submitted to a panel of experts and a score is awarded. The higher the score the worse the hips. In order to reduce the incidence of the disease in the more HD prone breeds the advice is to select a mate with a score lower than that of your dog. In this way you will be reducing the possibility of producing badly affected puppies rather than increasing it. Obviously in breeds in which the condition is not so common the responsible action is not to breed from affected dogs.

If I decide to breed is there anything else I can do to reduce the incidence of hip dysplasia?

There is evidence to indicate that dogs that grow very rapidly are more likely to have more severe hip dysplasia. Therefore it is suggested that feeding an adult type food to puppies of high risk breeds is worthwhile since it ensures that although nourished they grow more slowly. They still reach their full genetic body size but just not as rapidly. It is also important to avoid excessive exercise in the growing puppy particularly any climbing exercise. Therefore ban all running up and down stairs!

It is not necessary to treat your puppy as if handicapped but sessions of running or chasing thrown objects should be avoided during growth.

Is there anything else I ought to know?

If you wish to purchase a puppy from one of the HD prone breeds, it is always worthwhile ascertaining if the parents have been scored under the BVA/KC scheme and their respective scores. Bear in mind however that heredity is not the only factor involved and there is still a chance that parents with relatively low scores will produce some puppies with severe hip dysplasia.

Once you have gathered together all the relevant information, do not hesitate to contact us and we will do our best to advise you in the light of the evidence available.