Spinal injuries in patients with previous ankylosing spondylitis were reviewed retrospectively. Fractures frequently occurred as a result of minimal trauma and were associated with severe neurologic deficits in 75% of cases. A characteristic fracture pattern was seen radiographically, and appeared to result from the altered biomechanics of the ankylosed spine. Although the fractures were markedly unstable, nonoperative treatment was uniformly successful in achieving union. The incidence of complications and mortality in this group was significantly lower than that reported in other studies, and the authors attribute this to conservative management within a spinal cord injury unit.