寰枢椎椎弓根螺钉固定治疗创伤性寰枢椎不稳23例临床分析

Treatment of atlantoaxial instability with C_1-C_2 pedicle screw fixation and fusion with bone autografting:report of 23 cases

目的探讨寰枢椎椎弓根螺钉固定复位植骨融合治疗创伤性寰枢椎不稳的可行性。方法选取23例外伤所致寰枢椎脱位成年患者,男性16例,女性7例,年龄17～64岁,平均36.8岁;其中横韧带断裂5例,Anderson Ⅰ型齿状突骨折1例,Anderson Ⅱ型骨折11例,Anderson Ⅲ型骨折6例,均合并脊髓功能障碍。首先行颅骨牵引术力争寰枢椎复位,然后在气管插管全麻下实施颈后路寰枢椎椎弓根固定并自体髂骨植骨术。植骨面去皮质后,两块自体髂骨半板骨松质面铺于植骨床植骨。结果本组患者术中未发生椎动脉或脊髓损伤,术后随访8～25个月,神经功能获得改善;影像资料显示寰枢椎解剖关系恢复良好,螺钉位置好,术后无松动、断钉,植骨3个月椎体间达到稳定融合。结论寰枢椎椎弓根螺钉固定植骨融合治疗创伤性寰枢椎不稳是一种固定牢固,安全可靠的方法 。

Objective To explore the feasibility of C1-C2 pedicle screw fixation and fusion with bone autografting for treatment of atlantoaxial instability. Methods Twenty-three adult patients,16 males and 7 females with a mean age of 36.8 （ranging from 17 to 64）,with atlantoaxial dislocation in 2 h to 7 d （mean 18 h） after trauma were hospitalized in our department from January 2008 to December 2009. There were 5 cases having ligamentum transversum fracture,and 1 case of Anderson Ⅰ dens fracture,11 cases of Anderson II fracture,and 6 cases of Anderson Ⅲ fracture. All cases were accompanied with spinal cord dysfunction. After skull traction was carried out for 3 or up to 12 d until reset,these cases were treated with C1-C2 pedicle screw fixation and fusion with bone autograft under general anesthesia. The entry point of C1 pedicle screw in present technique was located on the vertical line through the central point of C2 lateral mass,and at least 3 mm under the superior rim of C1 posterior arch,15 in a medial inclination and 10 in a cephalic direction. The entry point of C2 pedicle screw was located in center of the medial-superior quadrant,30° in a medial in inclination and 30° in a cephalic direction. The screw diameter was 3.5 mm,and the screw length of C1 and C2 pedicle screws were 26 to 30 mm and 22 to 26 mm,respectively. The group of the patients were followed up for 8 to 25 months. Results No intraoperative complication such as injuries of vertebral artery or spinal cord occurred. During the follow-up,their clinical symptoms were improved to some extent. The postoperative X ray verified that not only the anatomic relationship between atlas and axis had restored well,but also all of pedicle screws were in a proper position without loosening,breaking or bending. The postoperative solid bone fusion was observed at 3 to 6 months after operation. Conclusion The approach of C1-C2 pedicle screw fixation and fusion with bone autografting is a good approach for atlantoaxial instability with immediate stability of the operative segments and postoperative solid bone fusion. It is an option for posterior surgical approaches to treat atlantoaxial instability.