Neurological complications of ankylosing spondylitis

Thirty-three patients with ankylosing spondylitis with or without spinal neurological symptoms requiring surgical intervention were identified in a retrospective review of all cases of spinal disorders treated at the Mayo Clinic during the period from 1984 to 1989. Spinal fractures (traumatic or pseudoarthroses), progressive spinal deformity, rotary instability secondary to atlanto-occipital or atlantoaxial subluxation, and spinal stenosis with associated neurological deficit, pain, or spinal instability were the most common indications for surgery. Of the 41 operations performed, there were 17 cervical, 14 thoracic, and 10 lumbar procedures. Eight patients had two or more disorders at separate spinal levels that required surgery. Preoperative neurological deficits were recorded in 13 patients; these improved following surgery in nine and stabilized in four. This review emphasizes the fragility of the ankylosed spinal column and its inherent susceptibility to fracture with attendant neurological compromise. It also identifies the variety of spinal disorders observed in these patients and discusses their surgical management. The experience with this series suggests that thorough radiological evaluation, extreme caution with endotracheal intubation and with halo-vest applications, early surgical spinal immobilization, and aggressive postoperative mobilization of patients are necessary for a successful outcome. It is concluded that outcomes in these patients can be favorable when managed appropriately.