Abstract: Objective To study the efficacy of posterior lamina internal fixation for the treatment of atlantoaxial dislocation with craniovertebral junction region malformation. Methods In April 2010 to November 2011, 12 patients suffered from atlantoaxial dislocation complicated with craniovertebral junction region malformation were treated at our department. All patients underwent posterior decompressed reduction and screw-titanium rod (plate) system internal fixation. CT thin layer scanning and 3D CT reconstruction were performed. Pre-and post-operative atlanto-dental interval (ADI), Chamberlain's line (CL) distance and McRae's line (ML) distance were measured. The degree of spinal cord compression was evaluated by cervicomedullary angle (CMA). Japanese Orthopaedic Association (JOA) score was used to assess the improvement of cervical medullary function. Electroneurophysiology was applied to detect nerve conduction function. Clinical effect of this surgical procedure was analysed. Results All patients were followed up for 4-20 months (mean 13 months). The differences of preoperative and postoperative ADI [(4.42 ± 2.91) mm vs (2.96 ± 2.08) mm], CL [(10.31 ± 3.80) mm vs (7.16 ± 3.19) mm], ML [(3.24 ± 2.92) mm vs (0.29 ± 2.36) mm], CMA [(127.83 ± 8.75)° vs (134.10 ± 8.38)°] and JOA [(9.75 ± 2.59) scores vs (14.83 ± 2.94) scores] were all statistically significant. In electroneurophysiological examination, preoperative waveform was abnormal in 10 cases, while 7 cases recovered to normal. Imaging examination showed bony fusion at bone grafting area, and no abnormal appearances after internal fixation. In follow-up period no complication occurred. Conclusion Posterior lamina internal fixation for the treatment of craniovertebral junction region malformation with atlantoaxial dislocation is safe, feasible and effective.

Key words: Dislocations, Atlanto-axial joint, Spinal fusion, Cervical vertebrae, Bone screws

摘要： 目的  观察经后路椎板内固定术治疗颅颈交界区畸形合并寰枢椎脱位的临床疗效。方法  对2010 年4 月-2011 年11 月诊断明确的颅颈交界区畸形合并寰枢椎脱位的12 例患者进行经后路减压复位螺钉-钛棒（板）系统内固定术。应用CT 薄层扫描及三维CT 重建术测量手术前后寰齿间距（ADI）、硬腭枕骨大孔线（CL）和斜坡枕骨大孔线（ML）上方距离，通过延髓脊髓角（CMA）评价脊髓受压程度，以日本骨科协会（JOA）17 分评分系统评价颈脊髓神经功能改善程度；神经电生理学方法监测神经传导功能，同时分析经后路减压复位螺钉-钛棒（板）系统内固定术治疗颅颈交界区畸形合并寰枢椎脱位的可行性。结果  共随访4 ~ 20 个月（平均13 个月）。与手术前ADI［（4.42 ± 2.91）mm］、CL［（10.31 ±3.80）mm］、ML［（3.24 ± 2.92）mm］、CMA［（127.83 ± 8.75）°］及JOA 评分（9.75 ± 2.59）相比，手术后ADI［（2.96 ± 2.08）mm］、CL［（7.16 ± 3.19）mm］、ML［（0.29 ± 2.36）mm］减小，CMA［（134.10 ± 8.38）°］及JOA 评分（14.83 ± 2.94）增加，治疗前后比较差异具有统计学意义（P < 0.05 或P < 0.01）。其中，手术前神经电生理学监测波形异常的10 例患者中7 例术后完全恢复正常形态。术后MRI 检查显示，颅颈交界区减压充分，无一例出现内固定松动或断裂；随访期间植骨获得骨性融合，未出现并发症。结论  经后路椎板内固定术治疗颅颈交界区畸形合并寰枢椎脱位临床疗效满意，手术安全、可行。

关键词: 脱位, 寰枢关节, 脊柱融合术, 颈椎, 骨螺丝