Closed reduction of spondylolisthesis. An experience in 22 patients.

Twenty-two patients with spondylolisthesis were treated by closed reduction techniques with posterolateral arthrodesis. Ages ranged from 6 to 30 years, with an average of 18 years. Six patients were treated in skeletal traction. Postoperatively, two patients were immobilized in an ambulatory extension brace, 15 patients in a body cast incorporating one thigh, and five patients in a body cast incorporating Hoffman iliac pins and lumbar spinous process wires attached to an outrigger on the plaster. At an average of 40 months follow-up (range: 12-80 months), preoperative slip angle averaged 33 degrees, postreduction 12 degrees, and at follow-up, 11 degrees. The percent slip preoperative averaged 50%, postoperative 43%, and at follow-up, 40%. Complications included transient L5 radiculopathy in two patients treated in skeletal traction and loss of correction requiring anterior interbody fusion.