经口前路寰枢椎侧块关节融合器的力学稳定性评价

目的　评价经口前路寰枢椎侧块关节融合器在前路经口寰枢椎复位固定钢板（TARP）及后路寰枢椎椎弓根钉棒（后路C1-C2钉棒）固定下的力学稳定性，为临床应用提供理论依据。  方法　采用自行设计的经口前路寰枢侧块关节融合器，将6具新鲜上颈椎标本，随机分为完整对照组(M)、前路TARP+髂骨块组(A1)、前路TARP+cage组(A2)、后路C1-C2钉棒＋髂骨块组(B1)、后路C1-C2钉棒＋cage组(B2)。 利用Motion Analysis, co.6 Eagle系统对屈伸、侧屈、旋转方向运动范围（ROM）进行测量，并行统计学分析。  结果　相同固定方式组间比较，cage组比髂骨块组运动范围更小，屈伸方向稳定性依次为A2＞B2＞A1＞B1， 其中A1与A2比较， 有显著性差异（P=0.0125）， B1与B2比较， 有显著性差（P=0.0132）；相同置入物组间比较， 前路TARP与后路C1-C2钉棒固定力学稳定性无显著性差异(P>0.05)。  结论　寰枢椎融合术中使用cage比髂骨块具有更好的三维稳定性、理论上能够提高寰枢椎融合率，减少并发症。

Biomechanical evaluation of stability of implantation of transoralatlantoaxial lateral mass fusion cage

Objective　To evaluatethe biomechanical properties of the fusion cage combined with Type ⅢTransoralAtlantoaxial Reduction Plate(TARP) system and posterior C1-C2 pedicle screw-rods system. Methods　6 fresh-frozen human cervical spines were used for study in five different groups. Range of motion (ROM) in flexion-extension, left-right bending, and axial rotation was recorded by Motion Analysis, co.6 Eagle.    Results　According to the anatomic data, the ring shape of the cage was feasible and the parameters: 3.5 mm height, 6 mm inner diameter, and 12mmouter diameter. The cage was made of Poly Ether EtherKetone(peek).The difference in stiffness between the TARP and C1-C2screw-rods was not statistically significant in the same implant groups. The ROM of cage groups was smaller compared with ilium groups and the difference in flexion-extension was statistically significant.　Conclusions　TARP system fixation or pedicle screw-rods fixation was significantly stiffer than the iliumgroup in atlantoaxial fusion. Moreover, smaller postoperative complications render it to have a better prospect of clinical application in clinical practice.