经寰椎后弓上颈椎稳定性重建的解剖学研究

目的 通过解剖学测量,探讨经寰椎后弓螺钉固定重建上颈椎稳定性的解剖学基础.方法 测量39具干燥寰椎标本椎管内径宽度、螺钉进钉点后弓高度和宽度、寰椎椎动脉沟底后弓高度和宽度、经后弓螺钉固定钉道长度和侧块钉道长度、后弓固定与侧块固定进钉角度等解剖学数据.统计学分析所测量数据并对经寰椎后弓螺钉固定钉道长度与经侧块螺钉固定钉道长度两组数据配对student t检验,检验水准为α=0.05.结果 寰椎椎管内径宽度为(26.80±2.58)mm;进钉点寰椎后弓高度和宽度分别为(6.83±1.97)mm和(6.40±1.36)mm;椎动脉沟底后弓高度和宽度分别为(4.37±1.11)mm和(8.05±1.33)mm;经后弓螺钉固定钉道长度为(30.54±1.70)mm.进钉点置钉时钉道外倾角度为15°～20°、吻侧前倾角度为0°～5°.椎动脉沟底骨质高度小于颈椎常用螺钉直径3.5 mm的占25.6%(10具).经侧块螺钉固定钉道长度为(16.91±1.13)mm,进钉点置钉时钉道内倾角度为32.05°±6.03°、头侧前倾角度为5°.经后弓螺钉固定钉道长度与经侧块钉道长度两组数据配对student t检验统计分析结果显示差异有统计学意义(t=59.528,P＜0.001).结论 约有74.4%的人群可顺利经寰椎后弓螺钉固定完成上颈椎稳定性的重建,该技术不仅可使寰椎得到即刻、牢靠的稳定性,同时较寰椎经侧块螺钉固定技术具有较小的手术风险和操作难度,是一项具有推广价值的寰椎稳定技术.

Abstract：

Objective To investigate the anatomy of upper cervical vertebrae's stable reconstruction by poster arch of atlas screw by anatomic study. Methods To collect the anatomical data of 39 dry atlas with the average inner diameter of vessel of atlas, the average high and wide of the screw point of poster arch of atlas, the average high and wide of poster arch of atlas beneath the groove for vertebral artery, the tract length of poster arch screw, the tract length of lateral mass screw, the direction and angle of poster arch screw, and the direction and angle of lateral mass. Statistical comparison were performed with Student test between the tract length of poster arch screw and the tract length of lateral mass screw. Results The average inner diameter of vessel of atlas was (26.8±2.58) mm(21.7-31.0 mm). The screw point high and wide of poster arch of atlas were (6.83±1.97) mm and (6.40±1.36) mm respectively. The average high and wide of poster arch of atlas beneath the groove for vertebral artery were (4.37±1.11) mm and (8.05±1.33) mm respectively. The tract length of poster arch screw were (30.54±1.705) mm. The direction and angle of poster arch screw was 15°-20° incline laterally and 0°-5°incline cephalo. 25.6%(10 cases) patients with the diameter less than 3.5mm beneath the groove for vertebral artery. The direction and angle of lateral mass screw was 32.05°±6.03° incline medially and 5° incline cephalo. There were significant differences between the tract length of poster arch screw and the tract length of lateral mass screw(t=59.528, P＜0.001 ). Conclusion About 74.4% patients can reconstruct the upper cervical stable by poster arch of atlas screw. The technique can gain instant upper cervical stable, and reduce the risk of injury of blood vessel by over explore the atlas arch compare with the technique of lateral mass screw fixation of atlas. The technique is worth to promoting with its character of safe, easy perform and rigid fixation.

Anatomic study of upper cervical reconstruction by posterior arch of atlas

Objective To investigate the anatomy of upper cervical vertebrae's stable reconstruction by poster arch of atlas screw by anatomic study. Methods To collect the anatomical data of 39 dry atlas with the average inner diameter of vessel of atlas, the average high and wide of the screw point of poster arch of atlas, the average high and wide of poster arch of atlas beneath the groove for vertebral artery, the tract length of poster arch screw, the tract length of lateral mass screw, the direction and angle of poster arch screw, and the direction and angle of lateral mass. Statistical comparison were performed with Student test between the tract length of poster arch screw and the tract length of lateral mass screw. Results The average inner diameter of vessel of atlas was (26.8±2.58) mm(21.7-31.0 mm). The screw point high and wide of poster arch of atlas were (6.83±1.97) mm and (6.40±1.36) mm respectively. The average high and wide of poster arch of atlas beneath the groove for vertebral artery were (4.37±1.11) mm and (8.05±1.33) mm respectively. The tract length of poster arch screw were (30.54±1.705) mm. The direction and angle of poster arch screw was 15°-20° incline laterally and 0°-5°incline cephalo. 25.6%(10 cases) patients with the diameter less than 3.5mm beneath the groove for vertebral artery. The direction and angle of lateral mass screw was 32.05°±6.03° incline medially and 5° incline cephalo. There were significant differences between the tract length of poster arch screw and the tract length of lateral mass screw(t=59.528, P＜0.001 ). Conclusion About 74.4% patients can reconstruct the upper cervical stable by poster arch of atlas screw. The technique can gain instant upper cervical stable, and reduce the risk of injury of blood vessel by over explore the atlas arch compare with the technique of lateral mass screw fixation of atlas. The technique is worth to promoting with its character of safe, easy perform and rigid fixation.