[Anterior vertebral reconstruction of the thoracic and lumbar spine using Hall-Dwyer instrumentation with distraction].

The Hall-Dwyer instrumentation was used in 64 patients presenting with anterior lesions of the spine. The system was applied on the vertebral bodies; it included Dwyer screws and staples and the Hall rigid rod. Manual distraction on the rod returned normal intervertebral spaces. Results are presented according to the aetiology. In fractures (15 cases) the mean kyphosis was reduced from 24 degrees to 6 degrees. When posterior ligaments were damaged, a complementary posterior osteosynthesis was necessary to provide stability. In kyphosis (5 cases) the kyphosis was reduced from 52 degrees to 21 degrees. At 24 months follow-up, the angular loss was 1 degree. In tumors (36 cases) a corporectomy was performed in 33 cases and a total vertebrectomy in 3 using methylmethacrylate or bone graft for reconstruction. A good postoperative stability was observed in all patients. In discopathies (5 cases) bony fusion was observed in all cases. Distraction improved the intervertebral height and the lumbar lordosis. Lastly the instrumentation was used in 3 patients with Pott's disease. One injury of the aorta was observed at removal of the instrumentation 18 months later. Mechanical complications occurred: rupture of the head of the screw (1 case), sliding of the rod in the eyelet with loss of correction (2 cases), fractures of the rod (1 case) or screws (5 cases). These complications suggest the magnitude of load applied on the material.