枢椎椎板螺钉治疗上颈椎不稳的临床研究

目的探讨枢椎椎板螺钉技术的临床应用和适应证。方法2004年10月至2008年12月,采用后路枢椎椎板螺钉技术治疗上颈椎不稳35例,男19例,女16例;年龄23～73岁,平均45岁。AndersonⅡ型和Ⅲ型齿突骨折19例,寰椎横韧带断裂1例,先天性游离齿突并寰枢椎不稳2例,寰椎骨折合并寰枢椎不稳7例,不典型Hangman骨折并C2-3不稳1例,C2-3创伤性不稳5例。患者均采用颈椎后路Vertex钉棒系统固定。结果35例患者共置入枢椎椎板螺钉68枚,术中无一例发生脊髓和椎动脉损伤。患者均获得随访,随访时间6个月～4年,平均25.5个月。随访时X线片均未见明显颈椎不稳、内固定失败及螺钉松动退出。11例患者螺钉穿出椎板背侧,但无症状出现。结论枢椎后路经椎板螺钉技术固定牢固,操作简单,相对安全,特别适用于C2椎弓根发育异常或骨折不能采用椎弓跟固定的患者。

Clinical application of C2 laminar screws technique for upper cervical spinal instability

Objective To explore the clinical outcomes and indications of C2 laminar screws technique.Methods From October 2004 to December 2008,35 cases with upper cervical spinal instability undergoing the C2 laminar screw fixation were reviewed.There were 19 males and 16 females,with a mean age of 45 years old（ranged 23 to 73 years old）. There were 19 cases for odontoid fracture,1 case for the rupture of Axis transverse ligament,and 2 cases for congenital loose odontoid process.7 cases for Jefferson fracture combined with atlantoaxial instability,5 cases for traumatic instability of C2-3,1 case for atypical Hangman fracture.All cases had the symptoms of atlantoaxial instability such as craniocervical junction pain,and were fixed with Vertex cervical internal fixation system.A total of 68 screws were placed,Hybrid constructs （a C2 translaminar screw combined with a C2 pars screw） were incorporated in 2 patients,and the patients were assessed both clinically and radiographically with postoperative computed tomographic scans.Results There were no intraoperative complications and no cases of neurological worsening or vascular injury from hardware placement.Computed tomographic scans demonstrated a partial dorsal laminar breach in 11 patients.None of these resulted in neurological symptoms. No patients were found to have a breach of the ventral laminar cortex.All the C2 laminar screws fixation were performed successfully,with a total of 68 screws inserted.There were no spinal cord and vertebral artery injury during surgery.There was no instability seen on these films with no evidence of hardware failure or screw loosening during the follow-up period in all patients.Conclusion Crossing C2 laminar screws provide the surgeon with an expanded armamentarium for fixation in the high cervical spine.This technique is straightforward and easily adopted.Posterior C2 laminar screw fixation is an efficient and reliable technique for it has the advantages of strong stability,relatively simple and safe operating,especially using a l