骨膜下剥离显露法在寰椎椎弓根螺钉固定术中的应用

Application of the subperiosteal exposure method for atlas pedicle screw fixation

[目的]分析评估经寰椎后弓侧块（椎弓根）螺钉固定术置钉过程中利用骨膜下剥离显露法（subperiosteum exposure method,SEM）保护寰椎后弓周围的重要血管和神经的有效性和安全性。[方法]自2009年6月~2013年6月,回顾性分析利用经寰椎椎弓根螺钉固定术治疗寰枢椎脱位患者76例,男47例,女29例;年龄5~64岁,平均40.1岁。寰椎置钉均采用经寰椎椎弓根固定技术,共置入螺钉152枚,置钉过程中,均采用SEM保护寰椎后弓上的椎动脉（vertebral artery,VA）和后弓下方的静脉窦与C2神经根。术后给予X线片、CT评估融合状态。JOA评分评估功能恢复情况。[结果]所有患者均成功完成手术,平均手术时间161 min（90~240 min）;平均出血量279 ml（150~450 ml）。置钉过程中无脊髓损伤,无椎动脉出血。静脉窦出血3例,应用明胶海绵压迫后止血,静脉窦出血率为4.0%。其中70例患者获得随访,平均随访时间22.7个月（6~84个月）。随访过程中无C2神经支配区域的枕部麻木或疼痛;无椎动脉损伤的症状和体征;无螺钉松动、移位,平均植骨融合时间4.6个月（3~9个月）;JOA评分从术前的（8.83±2.77）分提高到术后的（13.69±3.25）分（P〈0.05）。[结论]在经寰椎椎弓根螺钉固定术中,SEM提供了有效可行的保护寰椎后弓上下重要血管和神经的方法,成为寰椎后弓手术操作中重要的辅助技术。

[ Objective] To analyze the effectiveness and safety of the subperiosteal exposure method （SEM） for the atlas screw technique via the posterior arch and lateral mass （pedicle） . [ Methods ] Seventy - six patients （47 males, 29 females ; mean age, 54. 5 years ; age range, 5 - 64 years） with atlantoaxial dislocation were analyzed retrospectively between June 2009 and June 2013. All patients underwent atlas pedicle screw fixation with the screws inserted via the atlas pedicle. A total of 152 screws were inserted. The SEM was used to protect the vertebral artery （VA） superior to the C1 posterior arch, and venous sinus and C2 nerve root inferior to the C1 posterior arch during insertion of the screw. [ Results] The surgery was successful in all the patients. The average operative time was 161 min （range, 90 -240 min）, and the average blood volume was 279 ml （ 150 -450 ml） . There were no incidents of spinal cord injury or VA bleeding. Venous sinus bleeding occurred in 3 cases （rate of bleeding, 4. 0% ） , and the bleeding was stopped with gelatin sponge. Seventy patients achieved follow - up; the average follow - up period was 22.7 months （6 -48 months） . There were no occurrences of occipital neuralgia in the distribution of the C2 nerve root, vertebral artery injury, or loosening of screws. The average period of bone fusion was 4. 6 months （3 - 9 months）, and the average preoperative Japanese Orthopedic Association score of （8. 83 ± 2. 77） increased to （ 13.69 ± 3.25 ） （P 〈 0. 05 ） postoperatively. [ Conclusion] SEM is effective and feasible to protect the important vessels and nerves surrounding the C1 posterior arch during atlas pedicle screw fixation, and therefore, has become an important assistive technology for the atlas pedicle screw technlque.