Ankylosing spondylitis and trauma: the medicolegal implications. A comparative study of patients with non-specific back pain.

Ankylosing spondylitis (AS) arising as a result of injury was reported by five of 113 hospital patients who completed questionnaires on the historical and symptomatic features of their disease. Identical questionnaires were given to a group of 51 patients with non-specific back pain (NSBP) attending an orthopaedic clinic. Five of these patients developed their first symptoms after trauma. A further four patients with ankylosing spondylitis believed that their disease was initiated by injury, however, x-ray photographs showed that they had already developed AS at the time of their injuries. It is suggested that injury does not cause AS but brings it to the patient's attention, possibly through immobilisation, in 7% of hospital cases.