Ankylosing spondylitis: experience in surgical management of 21 patients.

Between 1976 and 1984, twenty-one patients with ankylosing spondylitis were treated surgically. Eight patients with rigid thoracic kyphosis underwent a two-stage combined procedure. The average correction was 36 degrees. Eight patients underwent a single-stage lumbar osteotomy with Harrington compression instrumentation. The average correction was 31 degrees. Five patients presented with stress fractures and back pain. All underwent combined anterior and posterior surgery. The average correction was 9 degrees. Two patients underwent anterior decompression for progressive paraplegia. Both showed improvement in neurologic function. At follow-up, all but one patient had improvement in pain and spinal alignment. There have been no deaths or persistent neurologic problems from these procedures.