Abstract
BACKGROUND: Few studies reported treatment of unstable traumatic spondylolisthesis of the axis using posterior fixation without fusion. The aim of this study was to evaluate the results and feasibility of posterior fixation without fusion in treating unstable traumatic spondylolisthesis of the axis. METHODS: Eleven patients with traumatic spondylolisthesis of the axis were included in this study, and posterior fixation without fusion using screw-rod system was performed for them. The clinical outcomes were assessed using the Visual Analog Scale (VAS), the Neck Disability Index (NDI), and the Odom's grading system. Plain radiography was used to measure the displacement and angulation of C2-C3, and cervical lordosis. Plain radiography and computed tomography were also used to observe the bony fusions of fracture lines and postoperative spontaneous fusion of C2-C3. RESULTS: The mean follow up time was 24.6 months (range, 12-72 months). The VAS and NDI scores were significantly improved at the final follow-up compared with those before operation (P < 0.05), and according to Odom's criteria, 90.9% (10/11) of patients rated their level of satisfaction as excellent or good. The angulation and displacement of C2-C3, and cervical lordosis were significantly improved after operation compared with those before operation (P < 0.05), and at the final follow-up, and these radiological parameters were maintained. All patients achieved solid bony fusions of fracture lines. No operative segment instability was found in all patients during the follow-up period. Spontaneous fusion at bilateral C2-C3 facet joints was found in 11 cases, and anterior and/or posterior bony bridge of intervertebral bodies at C2-C3 was found in 9 cases. CONCLUSIONS: Posterior fixation without fusion may be a feasible and effective option for unstable traumatic spondylolisthesis of the axis.