寰椎提拉螺钉术中复位治疗寰枢椎脱位

Surgical treatment with atlas drawing back reduction pedicle screws for reduction of atlantoaxial dislocation

目的总结应用寰椎椎弓根提拉螺钉结合枢椎椎弓根螺钉行后路提拉复位固定植骨融合术治疗寰枢椎脱位的疗效。方法2010年1月一2014年12月本院共收治27例寰枢椎脱位患者，均有不同程度的枕颈部疼痛和活动受限，并伴有神经功能障碍，美国脊髓损伤协会(ASIA)分级：B级2例，C级17例，D级8例； 日本骨科学会(J0 A )评分4~14分，平均8.3分。MRI示20例患者有不同程度的脊髓受压，其中8例脊髓受压节段髓内出现T2加权像高信号改z变。患者均为寰椎前脱位，术前均进行颅骨牵引，17例部分复位，10例不可复位。术前寰齿间距(A D I)4~15 mm，平均10.3 m m ;颈髓延髓角（C M A )im 0~135.70, 平均120.9〇〇均采用寰椎椎弓根提拉螺钉结合枢椎椎弓根螺钉行后路提拉复位固定植骨融合术，观察患者术后临床症状和神经功能改善情况及寰枢椎复位和植骨融合情况。结果所有患者均顺利完成手术，术中均未发生椎动脉和脊髓损伤。患者随访6~36个月，平均20个月。术后CT及MRI示寰枢椎序列重建满意，齿突区域脑脊液线清晰，脊髓无压迫。术后6个月随访时患者神经功能明显改善，2例B级患者提高至C级；17例C级患者中2 例提高至E 级，15例提高至D级；8例D级患者均提高至E 级。J0A评分10~17分，平均14.6分，平均改善率78.4%。术后ADI 2~4 m m ,平均2.6 mm; CMA139.2。~152.4。，平均144.6。。术后6个月随访时所有患者获得骨性融合；随访期间未发现螺钉松动、移位和断裂及寰枢椎再移位、失稳现象。结论寰枢椎脱位会造成寰枢椎不稳及脊髓受压，应用寰椎椎弓根提拉螺钉结合枢椎椎弓根螺钉后路提拉复位技术治疗可获得良好的临床效果。

Objective To summarize the clinical effect of the atlas drawing back reduction pedicle screw-rod combinedwith axis pedicle screw internal fixation with its intraoperative reduction and fusion in treatment of unreducible atlantoaxialdislocation. Methods From January 2010 and December 2014, the clinical and radiographic records of 27 atlantoaxialdislocation patients were analyzed retrospectively. All patients had different degree of pain and activity limitation, andaccompanied with neurological dysfunction. According to American Spinal Injury Association( ASIA ) grading system, 2patients were graded, as grade B, 17 grade C, 8 grade D. Japanese Orthopaedic Association ( JOA ) score before operation was4-14, mean 8.3. Preoperative MRI showed spinal cord compression in 20 patients, and T2WI high signal change was found in 8patients. All the patients had undergone skull traction before operation, and 17 patients were partially reduced, 10 not reducedat all. The preoperative atlantodental intervals ( ADIs ) were 4-15 mm, mean 10.3 mm. The preoperative cervico-medullaryangle ( CM A ) was 113.1° -135.7°, mean 120.9°. All patients were treated by the atlas drawing back reduction pedicle screw-rodcombined with axis pedicle screw reduction fixation and bone grafting fusion. The postoperative clinical symptoms, improvementof the neurological function, the atlantoaxial reduction condition and bone fusion were observed. Results All the surgerieswere performed successfully, and no intraoperative vertebral artery injury and spinal cord injury were noted. Postoperative-6-month CT and MRI showed that the cervical spine sagittal alignment was restored, and cerebral spinal fluid line was clearin the odontoid process area, and no spinal cord compression was found. All the patients were followed up for 6-36 months,mean 20 months. Neurological function was significantly improved after 6-month follow-up, 2 grade B cases recovered to gradeC; in 17 grade G cases, 2 recovered to grade E, and 15 recovered to grade D; 8 grade D cases recovered to grade E. Thepostoperative JOA score was 10-17, mean 14.6; the mean improvement rate was 78.4%. The postoperative ADI was reducedto 2-4 mm, mean 2.6 mm. The postoperative CM A was 139.2°-152.4°, mean 144.6°. Solid bony fusion was achieved in allpatients at postoperation 6 months, without loosening, displacement, or breakage of the screws and atlantoaxial instabilityor displacement. Conclusion Early surgical fusion is recommended for atlantoaxial dislocation causing instability and cordcompression. Good clinical results can be achieved by atlas drawing back reduction pedicle screw-rod combined with axis pediclescrew reduction fixation and bone grafting fusion.