The elbow (specifically the capitulum of the humerus) is the second most affected joint with 6% of cases; the talar dome of the ankle represents 4% of cases. Less frequent locations include the patella, vertebrae, the femoral head, and the glenoid of the scapula.The oldest case of OCD was identified on the temporo-mandibular joint of the Qafzeh 9 fossil. History
The condition was initially described by Alexander Monro (primus) in 1738. In 1870, James Paget described the disease process for the first time, but it was not until 1887 that Franz König published a paper on the cause of loose bodies in the joint. In his paper, König concluded that:
Trauma had to be very severe to break off parts of the joint surface. Less severe trauma might contuse the bone to cause an area of necrosis which might then separate. In some cases, the absence of notable trauma made it likely that there existed some spontaneous cause of separation.König named the disease "osteochondritis dissecans", describing it as a subchondral inflammatory process of the knee, resulting in a loose fragment of cartilage from the femoral condyle. In 1922, Kappis described this process in the ankle joint. On review of all literature describing transchondral fractures of the talus, Berndt and Harty developed a classification system for staging of osteochondral lesions of the talus (OLTs). The term osteochondritis dissecans has persisted, and has since been broadened to describe a similar process occurring in many other joints, including the knee, hip, elbow, and metatarsophalangeal joints.
X-rays are usually taken three months after the start of non-operative therapy; if they reveal that the lesion has healed, a gradual return to activities is instituted. Those demonstrating healing by increased radiodensity in the subchondral region, or those whose lesions are unchanged, are candidates to repeat the above described three-month protocol until healing is noted. Surgery
The choice of surgical versus non-surgical treatments for osteochondritis dissecans is controversial. Consequently, the type and extent of surgery necessary varies based on patient age, severity of the lesion, and personal bias of the treating surgeon—entailing an exhaustive list of suggested treatments. A variety of surgical options exist for the treatment of persistently symptomatic, intact, partially detached, and completely detached OCD lesions. Post-surgery reparative cartilage is inferior to healthy hyaline cartilage in glycosaminoglycan concentration, histological, and immunohistochemical appearance. As a result, surgery is often avoided if non-operative treatment is viable. Intact lesions
If non-surgical measures are unsuccessful, drilling may be considered to stimulate healing of the subchondral bone. Arthroscopic drilling may be performed by using an antegrade (from the front) approach from the joint space through the articular cartilage, or by using a retrograde (from behind) approach through the bone outside of the joint to avoid penetration of the articular cartilage. This has proven successful with positive results at one-year follow-up with antegrade drilling in nine out of eleven teenagers with the juvenile form of OCD, and in 18 of 20 skeletally immature people (follow-up of five years) who had failed prior conservative programs.