经寰椎"椎弓根"螺钉内固定技术的临床应用

目的：探讨经寰椎“椎弓根”螺钉内固定技术的手术可操作性和临床疗效。方法：对42例寰枢椎脱位并有高位颈脊髓受压症状及体征的患者应用经寰椎“椎弓根”螺钉内固定技术治疗，术前均行X线、CT等影像学检查；术中在直视下行C1、C2置钉，复位固定，椎板后弓植骨。其中16例难复性寰枢椎脱位采用经口腔前路松解，一期后路经寰椎“椎弓根”螺钉复位固定融合。术后颈托固定3个月。结果：42例84枚螺钉均成功置入，复位固定满意。术后36例获3-42个月随访，平均18．6个月，患者均在3～6个月寰枢椎骨性融合，未发现螺钉松动、断钉和寰枢椎再移位现象。其中4枚螺钉穿入椎动脉孔内缘1mm，但无椎动脉损伤的临床表现。31例患者脊髓功能明显改善，5例好转。结论：经寰椎“椎弓根”螺钉内固定技术具有直视下置钉、短节段固定、术中复位、融合率高等特点，为寰枢椎脱位患者的治疗提供了一种较好的内固定术式。

Clinical application of pedicle screw instrument in atlas

Objective:To explore the surgical feasibility and clinical outcome of pedicle screw instrument in atlas.Method:42 cases with atlas dislocation followed by upper cervical spinal cord compression treated surgically with pedicle screw instrument via atlas were reviewed.Of these 16 cases with irreducible atlas dislocation were treated surgically with oral anterior soft tissue release combined with posterior reduction and pedicle screw instrument.Preoperative CT and radiograph as well as intraoperative screw placement and bone graft were administered in all cases.Cervical collars as external support were used.Result:A total of 84 screws were successfully placed in atlas.Of 42 cases,36 cases were followed up from 3 to 42 months(on an average of 18.6 months).Bony fusion were observed in all 36 cases within 3 to 6 months without the complications of internal fixation failure and redislocation of atlas.4 screws penetratied into medial rim of the vertebral artery foramen,but no vertebral artery injury was documented.Neurological recovery was improved significantly in 31 cases,better in 5 cases.Conclusion:Pedicle screw instrument in atlas has the advantages of direct screw placement,short- segment fusion,intraoperative reduction and high fusion rate,it is a better alternative for atlas dislocation.