What is hip dysplasia?
Hip dysplasia is abnormal development of the hip joint that has a strong genetic component. The hip is a ball and socket joint. Affected animals have a normal joint at birth, but as the puppy grows and develops, the joint becomes slack which results in instability. Instability leads to partial dislocation of the joint and results in remodelling of the bone and abnormal shape of the hip and further instability. This leads to stretching of the joint tissues and abnormal loading of the joint resulting in inflammation, pain and damage to the cartilage, and even stress fractures in the bone underneath the cartilage. Damage to the joint cartilage progresses to irreversible arthritis in the hip.

Hip dysplasia typically affects large breed dogs such as Labradors, German Shepards and Rottweilers but can affect any breed of dog.

Does my dog have hip dysplasia?
The earliest signs of hip dysplasia are usually seen between 4 and 10 months of age. These can include stiffness after rest, difficulty getting up from a sitting / lying position reduced willingness to exercise (because of discomfort). A clinking sound can sometimes be heard from the joint itself as the dog walks. Dogs typically have there hind feet close together and walk with a short pottery gait and swaying of the hips. Dogs can appear to arch there back in an attempt to shift their weight on to the front legs.

How is a diagnosis made?
Manipulation of the hips reveals pain and characteristic instability. X-rays are useful to confirm the laxity and to show signs of early bony change / arthritis.

What can be done to treat hip dysplasia?
Unfortunately there is no way of making an affected joint normal. If left, the joints will remodel and eventually become stable, but arthritis will be present. Despite this many dogs (60% plus) with hip dysplasia / arthritis will be able to lead an active adult life style with little or no requirement for medication. It may take until approximately 18 months of age for this discomfort to subside.

It is very important that a dog’s weight is strictly controlled. Obesity will only add greater strain and abuse to an imperfect joint. Controlling your dogs exercise to levels that do not cause lameness can be very beneficial. Short frequent walks are better than long infrequent walks. Physiotherapy and hydrotherapy can help to build muscle mass.

Weight control and exercise modulation alone can be effective in many dogs. Some cases require anti-inflammatory medication, this is best used tactically as required rather than every day if possible.

Despite appropriate conservative management, the level of discomfort in some dogs may not be satisfactorily controlled, and consideration is given to surgical alternatives.

What are the surgical options?
In the juvenile (typically 6-10months old) if a diagnosis of hip dysplasia is made before significant cartilage damage occurs, surgery can be performed to improve the stability of the hip and try to limit the progression of arthritis (triple pelvic osteotomy).

In older dogs, total hip replacement is an option, and is aimed at restoring your dog to pain-free, mechanically sound, normal hip function.

Total hip replacement surgery involves removal of the abnormal ball (head of the femur) and socket (acetabulum) of the hip joint and replacement with prosthetic (artificial) implants. The new ball is made from cobalt-chromium metal alloy and the new socket from high-density polyethylene plastic. Following total hip replacement surgery, owners typically report their dog can do things they have not done since they were a puppy. Increase in muscle mass, improved hip motion and increased activity levels should be expected. The aim is for new artificial hip to work almost as well as a new hip.

An alternative surgical treatment to total hip replacement is Femoral Head and Neck excision Arthroplasty (FHEA)(removal of the femoral head). This prevents the abnormal painful head of the femur from contacting the abnormal painful hip socket and therefore provides pain relief. Scar tissue develops around the surgical site, holds the hip joint together and in some ways takes over the function of the old ball-and-scoket joint. This creates a false joint called psueod-arthrosis.

Total hip replacement is considered more reliable and more effective than FHEA in medium to large breed dogs but is a more involved surgical procedure and carries greater expense.

Is my dog a candidate for surgery?
The selection criteria for total hip replacement includes:
- Your dog has an abnormal hip that is causing significant pain and altered exercise tolerance.
- Your dog must be skeletally mature (finished growing). Generally this occurs by 12 months of age.
- The size and conformation of your dog’s hips are suitable for a Total Hip Replacement; this is determined by measurements taken from X-rays.
- Your pet is otherwise well and does not suffer from other conditions such as kidney failure, diabetes, pyoderma (infected skin) or recurrent cystitis (urinary tract infections)
- Non-surgical treatment methods (see below) have not worked.
- You are prepared risks of complications, and the associated cost, that may happen following Total Hip Replacement surgery.
 
A dog with arthritic hips that has pain-free, normal function is not a candidate for total hip replacement.

Which treatment option is most suitable for you and your dog depends on many factors. Conservative management is almost always the first option recommended. If this option is not effective then surgical options can be considered.

The best treatment option will be discussed with you in detail once we understand the needs of you and your dog, and once we have completed a thorough examination of your dog including gait evaluation, physical examination, X-rays, blood tests and or urine tests as appropriate.