Cervical spine fractures in patients with ankylosing spondylitis: Importance of early management.

INTRODUCTION

Ankylosing spondylitis (AS) affects 0.5% of the population. Alteration of the biomechanical properties of the spine related to AS explains the high prevalence of traumatic vertebral fractures and risk of instability. At admission, 65% of patients present neurological signs. There are no reported studies regarding secondary neurological deterioration. The aim of this study was to evaluate the rate of secondary neurological deterioration before surgical treatment of spine fracture in a context of AS.

METHODS

This retrospective cases series consisted of patients admitted for traumatic cervical spine fractures or luxation in a context of AS between June 2007 and December 2012. Clinical status was evaluated using Frankel classification at time of trauma, at admission to the neurosurgery ward, as well as before and after surgery. Delay between trauma and admission, and between admission and surgery was recorded. Causes of morbidity, mortality and surgical management were discussed.

RESULTS

During the study period, seven patients were admitted for traumatic cervical spine fracture or luxation. All patients were autonomous before trauma. Between trauma and transfer to neurosurgery ward, the status of four patients worsened. Mean delay between trauma and admission was 12.9 days (range 1 to 60 days). Between admission to neurosurgery ward and surgical treatment, two more patients worsened and only two patients remained autonomous. Mean delay between admission and surgery was 15.7h (range 2 to 24h). Neurological deterioration was due to both deterioration during transfer despite immobilization with a rigid cervical collar and failure of X-ray to reveal any fractures, in two and three cases respectively. After surgery, clinical status remained unchanged in two patients, four patients improved, and one patient worsened. Two patients died from respiratory failure a few days after surgery due to neurological deterioration. Five patients had a delayed diagnosis (>24h).

CONCLUSION

Cervical spine fracture in AS is a serious condition with high instability. Our series emphasizes the necessity of early surgical treatment because of risk of secondary neurological deterioration in cases of delayed treatment. CT scan must be the gold standard for exploration of these patients.