后路寰枢椎椎弓根螺钉短节段内固定治疗齿状突骨折并寰枢椎脱位

Treatment of odontoid process fracture combining atlantoaxial instability by posterior short segmental internal fixation with transpedicular screws

目的 总结应用寰枢椎椎弓根螺钉内固定术治疗齿状突骨折并寰枢椎脱位的临床疗效.方法 2009年1月～2012年1月收治36例齿状突骨折并寰枢椎脱位患者,男24例,女12例,年龄23～68岁,平均46.3岁.AndersonⅡ型齿状突骨折27例,不稳定Ⅲ型9例,术前日本骨科协会（JOA）评分 6～11分,平均9.6分,影像学检查均伴有寰枢椎不稳或脱位表现.采用经寰枢椎椎弓根螺钉进行固定,并在寰椎后弓与枢椎椎板间植入自体髂骨.结果 患者均顺利完成手术,术中未发生椎动脉和脊髓损伤.共置入144枚椎弓根螺钉,术后随访12~36个月,平均20.8个月,所有患者寰枢椎复位均满意.术后三维CT检查发现3例寰椎椎弓根螺钉内倾角偏小,螺钉部分穿破椎动脉孔内侧壁,椎动脉造影未见椎动脉损伤.其余病例螺钉位置满意,植骨于术后6～9个月达骨性融合.术后3个月JOA评分11～17分,平均14.6分.所有患者术后颈部屈伸活动良好,轴向旋转功能有部分丧失,无神经症状加重、螺钉松动、断裂和寰枢椎失稳现象发生.结论 应用后路寰枢椎椎弓根螺钉短节段内固定治疗齿状突骨折并寰枢椎脱位,可使寰枢椎获得即刻的坚强固定,有利于植骨融合,可获得良好的临床效果.

Objective To summarize clinical effects of treatment of odontoid process fracture combining atlantoaxial insta- bility by posterior short segmental internal fixation with transpedicular screws. Methods 36 patients of odontoid process fracture combining atlantoaxial instability, with 24 males and 12 females, and with average age 46. 3 year-old from 23 to 68, were treated from January 2009 to January 2012. There were 27 cases of Anderson II odontoid process fracture and 9 cases of type m atlantoaxial instability among them. Japanese Orthopaedics Association （JOA） scores before operation varied from 6 to 11 points, average 9. 6 points. Radiation image examination showed that all had atlantoaxial instability or dislocation. The patients received transpedicular screws fixation through atlantoaxial vertebral arch pedicle, and self-ilium implantation between posterior arch of atlas and vertebra dentata lamina. Results All operations were completed smoothly, with 144 vertebral arch pedicle lag screws being placed in, and without vertebral artery or spinal injury. The patients were followed up 12 to 36 months after operation, averagely 20. 8 months, showing satisfactory atlantoaxial restoration. Three dimensional CT scan after operation found out that inner incline angles were smaller for 3 case, and vertebral artery medial walls were partially punctured through by the screws, but vertebral artery contrast images showed no vertebral artery injury. The screws were positioned satisfactorily for the other cases. Implantationed iliums achieved osseous fusion 6 to 9 months after operation. JOA scores 3 months after operation varied from 11 to 17 points, the average was 14. 6 points. The cervical flexion and extension performed well for all post-treatment patients, with partial loss of axial rotation function. NO phenomenons such as neural symptom increasing, screw becoming flexible or broken, or atlantoaxial instability occurred. Conclusion Treatment of odontoid process fracture combining atlantoaxial instability by posterior short segmental internal fixation with transpedicular screws can bring instant firm fixation to atlantoaxis, thus be good for fusion of implantationed iliums, and obtain well clinical effects.