Purpose: A retrospective study of 17 fractures of the cervical spine in patients with ankylosing spondylitis is reported. The purpose of this study was to search for risk factors of fracture in ankylosing spondylitis an to assess treatment outcome.

Material and methods: Seventeen patients treated between 1982 and 2201 were reviewed with a mean follow-up of five years. There were three women and fourteen men, mean age 60 years at trauma. Fifteen patients underwent surgery and two were treated orthopaedically.

Results: This group of patients with ankylosing spondylitis with fracture of the cervical spine was homogeneous: age 60 years, disease duration 30 years, fracture due to fall. The fracture was at the C6/C7 level in 47% of the patients where the lever arm is the greatest and also a level that is difficult to explore, explaining the late diagnosis in 35% of the patients. Sixty percent of the patients were in Frankel classes D or E and 23% in classes A or B. Anterior fixation was used for 14 patients, posterior fixation in one. A long osteosynthesis involving several levels was used in all cases. Major kyphosis had developed in three patients after fracture which was not recognised initially; at fixation, an anterior wedge graft was inserted in the fracture line for correction. Mean correction was 20° with good restoration of the lordosis and rehorizontalization. Bone healing was achieved in all operated patients without loss of the reduction of the kyphosis at last follow-up. The neurological status did not worsen in any patient. Anterior fixation was insufficient to reduced an old fracture-dislocation in one patient who required posterior decompensation. Orthopaedic treatment was used in two patients: the first (Frankel A) died at two months and the second healed with a 10° aggravation of the cervical kyphosis. All the Frankel A and B patients in this series died.

Conclusion: All patients with severe neurological involvement died. The anterior approach, used alone, provided good stabilisation of the cervical spine. For the patients without neurological involvement, reduction of the cervical kyphosis should be associated with a stabilisation procedure in case of fracture with kyphosis.