Fig. Ia Fig. lb VOL. 77-B, No. 6, NOVEMBER 1995 975 BRIEF REPORTS TRANSCHONDRAL FRACTURE DISLOCATION OF THE SHOULDER DERMOT COLLOPY, ALLAN SKIRVING Transchondral fracture-dislocations of the shoulder are rare. Accurate reduction and rigid fixation are required to ensure revascularisation and healing of the ischaemic fragment. We report the satisfactory outcome of a transchondral fracture dislocation of the shoulder seven years after inter- nal fixation. Case report. A 20-year-old man was catapulted from his motorcycle at 80 km/hour, and presented with severe pain in his right shoulder. On examination there was flattening of the shoulder contour with a posterior bulge and abra- sions. No active or passive movements were possible, but neurological examination was normal and the wrist pulses were palpable. Radiographs showed posterior dislocation of a supero- medial fragment of the humeral head (Fig. 1). This was confirmed by CT (Fig. 2). Through a standard deltopectoral approach, subscapu- laris and the anterior capsule were released from the lesser tuberosity, and the large osteochondral fragment, carrying about 60% of the articular surface, was found firmly wedged behind the posterior rim of the glenoid. When this had been dislodged, an anatomical reduction was achieved with fixation by two counter-sunk, 4 mm AO cancellous screws. Recovery was uncomplicated; after eight weeks the patient had regained a normal range of movement. A bone scan after six months was reported to show revascularisa- tion of the osteochondral fragment. Seven years later, the patient had no complaints, a full range of movement and worked as a labourer. Radiographs suggested revascularisation with no joint-space narrowing (Figs 3 and 4). D. Collopy, Orthopaedic Registrar Nuffield Department of Orthopaedic Surgery, Nuffield Orthopaedic Cen- tre, Windmill Road, Headington, Oxford OX3 7LD, UK. A. Skirving, FRCS, Clinical Associate Professor St John of God Medical Centre, 175 Cambridge Street. Wembley 6014, Western Australia. Correspondence to Mr A. Skirving. ©1995 British Editorial Society of Bone and Joint Surgery 0301-620X/95/6R38 $2.00 J Bone Joint Surg [Br] l995:77-B:975-6. Received 18 May 1994; Accepted 15 July 1994 Discussion. Osteochondral fracture-dislocation involving most of the articular surface of the humeral head is rare, but Wilson and McKeever (1949) described a similar injury in a young epileptic patient which was not diagnosed for 20 days. Excision of a fragment comprising one-third of the articular surface gave a very poor result. Blasier and Bur- kus ( 1988) described two cases of osteochondral fracture associated with posterior dislocation, but in one the frag- ment included the lesser tuberosity, allowing extra-articular