A case of osteochondritis dissecans complicating Legg-Calvé-Perthes' disease is reported. Despite four years of conservative treatment in an ischial-bearing caliper a part of the fragmented femoral head failed to unite with the rest of the epiphysis and has persisted as an intra-articular loose body.

Freehafer (1960) listed the indications for surgical removal of this fragment in such cases: 1) persisting symptoms; 2) dislocation of the loose fragment into the joint with secondary arthritic changes inevitable; 3) a mechanical block to movement of the hip.

Since our patient had a relatively symptomless hip with a full range of movement, surgical removal of the loose body was not advised. The prognosis for this hip is nevertheless guarded, and surgery can be reserved for the above indications or for reconstructive procedures should they be required in the future.