OCD/ Osteochondritis dissecans (neurological: canine obsessive compulsory disorder)

Osteochondritis Dessicans, or OCD, is a problem with the cartilage in a young dog. Separating the metaphysis and the epiphysis in a young growing dog are the growth plates, or epiphyseal plates, made of cartilage and bone-forming cells. Covering the outside surface of the epiphysis is a layer of cartilage, or articular cartilage, which helps to minimize friction and wear of the bone when the joint moves.

In a young dog, sometimes a piece of the articular cartilage will tear away from the epiphysis and form a flap. This is OCD. The flap may reattach to the bone on its own, or it may tear away, becoming a joint mouse in the joint cavity. This joint mouse can cause pain if it is not ground into small pieces and absorbed. The flap may remain unchanged, causing pain and arthritic changes to the joint.

There are three things associated with causing OCD. Trauma can cause damage to the cartilage resulting in OCD. Genetics are thought to predispose a dog to OCD. Diet for the growing dog is also thought to be a factor. Excessive weight gain, calcium supplementation, and an overly nutritious diet are all to be avoided.

The signs of OCD are usually noticed in a dog as early as 4 - 10 months or as late as 12 - 18 months. It occurs more frequently in males. Although it can occur in almost any joint (hock, stifle, and elbow), it most commonly occurs in the shoulder. It is first apparent as mild limping, the affected joint can stiffen after resting, and the limping is aggravated by exercise. If OCD is left untreated, arthritic changes in the joint may cause permanent lameness.

Radiographs usually aid diagnosis, but manipulation of the joint will generally cause a pain response. Radiographs should be taken of the opposite joint as well, since OCD often occurs bilaterally.

Once the problem is diagnosed, the course of treatment is generally to allow 4 - 6 weeks of rest and restricted activity to give the joint a chance to heal on its own. Medication is not advisable because it causes the dog to feel better and more like playing. It is uncommon for the joint to heal on its own, but it is certainly worth a try. Some vets advocate moderate exercise in order to help the flap break away and get ground down and absorbed. If, after 6 weeks of rest no improvement is seen, surgery is the only other standard option.

If the OCD occurs on the humerus - the long bone in the upper foreleg - then the surgery has an excellent chance for a full recovery. Surgery for OCD in the elbow, hock, or stifle has more unpredictable results. The surgical procedure consists of cutting away the cartilage flap, removing any loose unattached cartilage, and searching the joint in order to remove any fragments that have already torn away. Activity is restricted for 1 - 2 weeks after surgery, after which time normal activity may resume. Within a month the dog's shoulder should be as sound as it was at the time of the surgery, and should continue to improve thereafter. There may be some arthritis in the joint eventually, but it will not always become symptomatic.

Preventing OCD may not be possible, but there are many things thought to help. A diet minimizing rapid growth, supplementation with vitamin C, and shark cartilage have all been used by list members with varying degrees of success.