Surgical Stabilization Improves Survival of Spinal Fractures Related to Ankylosing Spondylitis

STUDY DESIGN. National registry cohort study. OBJECTIVE. The aim of this study was to investigate the effect of surgical stabilization on survival of spinal fractures related to ankylosing spondylitis (AS). SUMMARY OF BACKGROUND DATA. Spinal fractures related to AS are associated with considerable morbidity and mortality. Multiple studies suggest a beneficial effect of surgical stabilization in these patients. METHODS. In the Swedish patient registry, all patients treated in an inpatient facility are registered with diagnosis and treatment codes. The Swedish mortality registry collects date and cause of death for all fatalities. Registry extracts of all patients with AS and spinal fractures including date of death and treatment were prepared and analyzed for epidemiological purposes. RESULTS. Seventeen thousand two hundred ninety-seven individual patients with AS were admitted to treatment facilities in Sweden between 1987 and 2011. Nine hundred ninety patients with AS (age 66 ± 14 years) had 1131 spinal fractures, of which 534 affected cervical, 352 thoracic, and 245 lumbar vertebrae. Thirteen percent had multiple levels of injuries during the observed period. Surgically treated patients had a greater survival than those treated nonsurgically [hazard ratio (HR) 0.79, P = 0.029]. Spinal cord injury was the major factor contributing to mortality in this cohort (HR 1.55, P < 0.001). The proportion of surgically treated spinal fractures increased linearly during the last decades (r = 0.92, P < 0.001) and was 64% throughout the observed years. CONCLUSIONS. Spinal cord injury threatened the survival of patients with spinal fractures related to AS. Even though surgical treatment is associated with a considerable complication rate, it improved the survival of spinal fractures related to AS. Level of Evidence: 3