Osteochondrosis dissecans (OCD)
OCD, an inheritable, juvenile bone disease, occurs when there is a defect in cartilage growth. It is common in large breed dogs and can occur in multiple joints. The joint typically affected is the shoulder but this disease can also be found in the stifle (knee), tarsal (hock), and elbow joints. The clinical presentation of OCD can vary from subtle signs to obvious clinical discomfort. There is usually a mild, weight-bearing lameness that frequently occurs after exercise, first thing in the morning, or upon rousing from a rest. Occasionally, the diseased cartilage will break loose and create what is called a "joint mouse." If this happens, the animal is usually non-weight bearing on the affected leg.
The diagnosis is generally made from a combination of orthopedic exam, radiographs, and an exploratory surgery of the affected joint. As stated earlier, the symptoms of OCD can be vague and mimic other orthopedic problems, which make the diagnosis difficult to confirm. Many times, the radiographs will reveal an OCD lesion or show secondary signs such as joint effusion. Other times, exploratory surgery is needed to verify the diagnosis (especially in the elbow).
Treatment for OCD consists of surgical removal of any joint mice and curetting the area of the lesion. Curetting involves removing any diseased cartilage and stimulating new fibrocartilage to replace it. Since there is a high degree of developing degenerative joint disease (DJD), adjunctive treatment with anti-inflammatory drugs (such as Rimadyl) and chondroprotective agents (such as Cosequin) can be beneficial.
Below are images of OCD in the shoulder joint of different canine joints. The arrows denote the OCD areas.
Shoulder OCD
Intraoperative OCD of the shoulder
