Spinal cord injury, spinal fracture, and spinal stenosis in ankylosing spondylitis.

The authors report a retrospective review of 105 patients with ankylosing spondylitis (AS) diagnosed over a 6-year period in Tucson, Arizona. In the series, there were 13 patients with spinal fractures and eight with severe spinal cord injury. Two patients with central cord contusion had no demonstrable cervical spine fracture. Injury was often trivial and dislocation at fractures sites was minimal, demonstrating the extreme fragility of these patients. Spinal stenosis, which has not previously been associated with AS, was documented in three cases. Pseudarthrosis, a destructive vertebral lesion that does not require surgical decompression or fusion, was found in four patients; this entity is believed to originate as a pathological or traumatic fracture. Atlanto-axial subluxation and basilar invagination associated with spinal ankylosis occurred in one patient. The study emphasizes the value of computerized tomography scanning of the spine for diagnosis, and halo-vest application as a nonoperative treatment for cervical immobilization. Early diagnosis and appropriate therapy to decompress, reduce, and immobilize unstable spinal lesions may result in reduction of the 29% mortality rate and 45% permanent neurological morbidity rate observed after spinal fracture in this series of AS patients. Because of the high operative complication rate observed, nonsurgical immobilization is the recommended treatment unless spinal dislocation or bone fragment displacement has occurred at the fracture site.