Elbow Dysplasia in the Dog

Elbow dysplasia is an inherited disease that primarily affects medium to large breed dogs (although some small breeds may be affected). It usually affects both elbows in young dogs and can lead to lifelong osteoarthritis and pain in these joints.   It is a complex syndrome and can involve one or more of the following conditions:

1. Osteochondrosis OCD (a loose piece of cartilage within the joint)
2. Fragmentation of the coronoid process FCP
3. Ununited anconeal process UAP
4. Elbow incongruity (a step in the joint surface causes by a difference in growth of the 3 bones that make up the elbow joint)

The elbow is a complicated joint comprising of 3 bones – the ulnar, radius and humerus, which act like a hinge joint.  The elbow is a high motion joint and a normal forelimb gait is more dependent on the elbow joint than any other joints. In a normal joint, the bones must all grow together and fit perfectly with a smooth lubricated surface.  In a dysplastic elbow the bones may grow at different rates causing a step in the joint and ultimately excessive pressure on certain parts of the joint.  This can lead to fragments (chips) of bone breaking off.  These fragments can cause constant irritation rather like a piece of grit in a door hinge! This can lead to pain, further joint damage and secondary arthritis of the joint. 

Cause:

The development of elbow dysplasia is primarily dependent on the genetic make-up of the dog.   Growth rate, diet and the level of exercise in young dogs may influence the severity of the disease – but generally the dog has to have a genetic predisposition to elbow dysplasia to develop it. 

Symptoms:

Dogs with elbow dysplasia will often have a noticeable limp.  Signs may be seen as early as 4 months of age but usually are seen between 6-12 months of age, however elbow arthritis is also seen in older dog as a consequence of elbow dysplasia from a young age.If both elbows are affected, your dog may have a short stilted forelimb gait and may also seem lazy and unwilling to play, and seem stiff when rising.  Your veterinarian may notice some joint swelling and often extension and rotation of the joint will be painful. 

Diagnosis:

Often clinical signs in a young large breed dog are suggestive of elbow dysplasia, however x-rays are imperative for a diagnosis. Your dog will need to be sedated as high quality x-rays are needed.  Some conditions of elbow dysplasia may be readily visible eg OCD, UAP and incongruity of the joint, but FCP may rely on visualizing secondary arthritic changes to the joint. 

Treatment:

Treatment varies depending on the severity of the problem. Conservative treatment involves weight loss, control of exercise and anti-inflammatory medications to relieve pain and control inflammation.  In addition it may be beneficial to add in omega oils and glucosamine for additional joint support.  In some instances the body may make compensatory adjustments to the growth of the bones to minimise unequal growth. Surgical therapy may be indicated with more severe cases to either remove cartilage flaps (OCD), remove bone chips, or newer therapy involves actually cutting through the ulnar bone to relieve pressure on the joint! 

Prognosis:

Unfortunately regardless of the treatment, the disease is progressive and most dogs with elbow dysplasia will develop secondary arthritis with advancing age.  Obviously the severity will be dependent on the degree of elbow dysplasia.

Prevention:

As mentioned previously, elbow dysplasia has a hereditary basis. It is therefore imperative to screen at risk breeds with an elbow x-ray, prior to using them for breeding.  One x-ray is taken after the dog is one year of age and sent to a panel of radiologists, who examine the x-ray.  They will then grade the x-ray depending on the changes visible.  Dogs with elbow scores free from changes consistent with elbow dysplasia, should only be used for breeding.   Prior to buying a medium/large breed puppy this is a question you should always ask your breeder.