Posterior reduction and instrumentation with rod-screw construct for atlanto-axial dislocation: A single institutional study with 21 consecutive cases

Abstract

Atlanto-axial dislocation is one of the leading causes for occipito-cervical instability. This study aimed for investigating the clinical outcome of rod-screw construct rather than traditional posterior wiring for atlanto-axial dislocation. Twenty one consecutive atlanto-axial dislocation patients undergoing surgery in our institution from April 2008 to May 2011 were retrospectively reviewed. Posterior reduction and instrumentation between occipital/C1 lateral mass and C2 pedicle, and concomitant occipital-atlanto-axial fusion were achieved with polyaxial-screw and rod construct. Clinical outcomes and complications were analyzed postoperatively at 3, 6, and 12 months. The satisfactory repositioning and internal fixation of the atlanto-axial joint, rigid screw placement and successful atlanto-axial fusion were confirmed in the 20 cases during follow-up. One patient died of a secondary ischemic injury to the brainstem 12 days after operation. The exception was a pediatric patient with loosened screws at 3 months follow-up postoperatively. Importantly, clinical symptoms and neurological function were significantly improved in all 20 cases during each follow-up as compared to preoperative scenarios. In addition, we noted that ischemic injury and screw detachment may be the main surgical risks. This surgical procedure provided satisfactory reduction of the atlanto-axial joint with significant neurological improvement. Moreover, we successfully avoided complications of posterior wiring.