寰枢椎后路固定补救方案的生物力学研究  

Biomechanical analysis of posterior atlantoaxial fixation

作　　者：金国鑫[1] 张磊[1] 阎崇楠[1] 刘齐[1] 王欢[1] JIN Guoxin;ZHANG Lei;YAN Chongnan;LIU Qi;WANG Huan(Department of Spine,Shengjing Hospital of China Medical University,Shenyang 110004,China)

机构地区：[1]中国医科大学附属盛京医院脊柱外科,沈阳110004

出　　处：《中国医科大学学报》2021年第1期25-29,共5页Journal of China Medical University

基　　金：辽宁省自然科学基金资助计划重点领域联合开放基金(2019-KF-01-09)。

摘　　要：目的研究寰枢椎后路补救方案治疗寰枢椎不稳的生物力学强度。方法利用新鲜尸体标本建立齿状突骨折模型,进行寰枢椎椎弓根螺钉(A组)和后路补救方案固定,双侧寰椎后弓螺钉+枢椎椎板钉(B组);左侧寰枢椎椎弓根钉+右侧寰椎后弓钉,枢椎椎板钉(C组);左侧寰枢椎椎弓根钉+左侧寰椎后弓钉,枢椎椎板钉(D组);双侧寰椎椎弓根钉+枢椎椎板钉(E组)。测量载荷下各方向活动度,并测量抗拔出力,比较生物力学强度。结果B组和E组对后伸的控制较A组弱(P<0.05)。左侧弯时,C组活动度降低50.5%,D组降低66%,与A组比较有统计学差异(P<0.05)。右侧弯时各组活动度均显著降低(P>0.05)。B组和C组左侧轴向旋转的控制活动度比A组大,B组右侧轴向旋转控制活动度与A组比较有统计学差异(P<0.05)。寰椎椎弓根螺钉的拔出力为718.2 N,后弓螺钉的拔出力为399.7 N。两者比较有统计学差异(P<0.05)。枢椎椎弓根螺钉拔出力为635 N,枢椎椎板螺钉拔出力为431.3 N,差异有统计学意义(P<0.05)。结论寰枢椎置钉困难时,左侧寰枢椎椎弓根钉+左侧寰椎后弓钉,枢椎椎板钉,双侧寰椎椎弓根钉+枢椎椎板钉可优先考虑,其次选择左侧寰枢椎椎弓根钉+右侧寰椎后弓钉,枢椎椎板钉。双侧寰椎后弓钉+枢椎椎板钉需要坚强外固定。Objective To determine the biomechanical stability of posterior atlantoaxial fixation.Methods We tested specimens in the intact,unstable,and fixated conditions.Specifically,the atlantoaxial ranges of motion and pullout strengths of the screws were assessed.The specimens were divided into five groups:bilateral atlantoaxial pedicle screws(group A);bilateral atlas posterior arch screw+axis laminar screw(group B);left side atlantoaxial pedicle screws with contralateral atlas posterior arch screw+axis laminar screw(group C);left side atlantoaxial pedicle screws with ipsilateral atlas posterior arch screw+axis laminar screw(group D).Angular motion was measured during testing,after which statistical analyses were performed.Results Groups B and E were weaker compared to group A with respect to atlantoaxial extension control(P<0.05).During left bending,the range of motion of group C decreased by 50.5%.Meanwhile,group D decreased by a statistically significant 66%compared to group A in the same regard(P<0.05).All groups showed decreased range of motion during right side bending(P>0.05).Groups B and C were weaker than group A(P<0.05)with respect to left axial rotation.Additionally,group B was weaker during right axial rotation.The pullout strength of the atlas pedicle screw,posterior arch screw,axial pedicle screw,and laminar screw were 718.2 N,399.7 N,635.0 N,and 431.3 N,respectively(P<0.05).Conclusion When screw implantation proves difficult,the following order of screw placement should be prioritized based on their respective biomechanical advantages:left side atlantoaxial pedicle screws+ipsilateral atlas posterior arch screws,axis laminar screws,bilateral atlas pedicle screws+axis laminar screw,left atlantoaxial pedicle screws+contralateral atlas posterior arch screw,and axis laminar screw.The combination of bilateral atlas posterior arch screw+axis laminar screw may require robust external fixation.

关 键 词：寰枢椎不稳 寰椎后弓螺钉 枢椎椎板钉 抗拔出力 

分 类 号：R68[医药卫生—骨科学]