[Outcome of femoral osteochondritis dissecans of the knee].

Osteochondritis dissecans is a radiological entity, corresponding to a juxta-articular bone fragment separated from the rest of the epiphysis by a radiolucent zone. Diagnosed prior to closure of the femoral growth plate, the abnormal image generally disappears without leaving any sequelae. No aggressive treatment is therefore indicated. The course of osteochondritis detected after closure of the femoral growth plate is different: the sequestrum always evolves spontaneously towards separation from the epiphysis to become an intra-articular foreign body. Osteochondritis in adults also predisposes to early osteoarthritis. Fixation of the sequestrum while it is still in place clearly protects the knee form osteoarthritic deterioration and should be proposed without hesitation whenever a periosteochondritic fissure is observed.