Posterior screw-rod fixation fusion for the treatment of atlantoaxial dislocation due to rheumatoid arthritis

Abstract

Objective To investigate the clinical effect of posterior screw-rod fixation fusion for the treatment of atlantoaxial dislocation due to rheumatoid arthritis. Methods From January 2011 to December 2015, 15 patients with atlantoaxial dislocation due to rheumatoid arthritis were treated, including 6 males and 9 females, aged 35 to 75 years (mean 55 years). All cases were evaluated about the difficulty of relocation by extension-flexion X-ray and treated with posterior screw-rod reduction, fixation and autogenous bone grafting under general anesthesia. Atlantodental interval (ADI) was measured and collected before and after surgery. Visual Analogue Scale/Score (VAS), American Spinal Cord Injury Association (ASIA) and Japanese Orthopaedic Association (JOA) scores were comprehensively used to evaluate the clinical effect. 1 week, 3, 6, 12 months postoperatively and the annual review of the X-ray and CT were checked, in order to evaluate the reduction, internal fixation and bone graft fusion. Results All patients were reducible dislocation and successfully performed the posterior screw-rod fixation fusion surgery. The patients were followed up for 3 to 24 months (average, 15 months). Atlantoaxial solid bony fusion was obtained from 3 to 6 months. ADI reduced from preoperative 6.3±1.7 mm to postoperative 2.2±0.8 mm, VAS score reduced from preoperative 5.4±2.7 to postoperative 1.7±1.0, ASIA motor score improved from preoperative 82.3±15.6 to 95.3±4.5 at 6 months after the surgery, JOA score increased from preoperative 13.8±2.9 to 15.5±1.4 at 6 months after the surgery, and the statistical significance was revealed between preoperation and postoperation. Nine cases were in D grade of ASIA, 3 cases improved from D to E grade after surgery, 2 cases reached E grade in the other 6 cases after 6 months, 2 cases recovered to E grade after 12 months and other 2 cases in D grade got uniformity after surgery. Well internal fixation and no redislocation were found on X-ray and CT during follow-up period. Conclusion Atlantoaxial dislocation because of rheumatoid arthritis was numerously reducible genre. Posterior screwrod fixation and autogenous bone grafting can gain satisfying clinical efficacy. Key words: Cervical atlas; Axis; Dislocations; Arthritis, Rheumatoid; Spinal fusion