Abstract：
BACKGROUND: Constrained inserts in total knee arthroplasty (TKA) may offer additional stability, but can this insert type allow unrestricted movements or will the extra conformity cause kinematic conflict with the cam-post mechanism in deeper flexion? The objective of this study was to evaluate the weight-bearing kinematics of both traditional and constrained bicruciate stabilized (BCS) TKA inserts to determine if the rollback induced by the cam-post mechanism will work in unison with the constrained polyethylene insert.
METHODS: This study used previously published 3-dimensional model fitting techniques to compare weight-bearing flexion and femoro-tibial condylar motion patterns for 20 patients who had a traditional insert, 20 patients who had a constrained insert, and 10 previously published nonimplanted knees, all performing a deep knee bend activity while under fluoroscopic surveillance.
RESULTS: The results from this study indicate that subjects having a bicruciate stabilized TKA experienced similar postoperative kinematics for both constrained and unconstrained insert options, comparable to normal knees.
CONCLUSIONS: Subjects in this study having either a constrained or traditional insert experienced progressive rollback of both condyles, with the lateral condyle rolling more posterior than the medial condyle, leading to axial rotation. Although less in magnitude, these results were comparable to the normal knee in pattern, indicating that kinematic conflict did not occur for subjects having a constrained insert.
METHODS: This study used previously published 3-dimensional model fitting techniques to compare weight-bearing flexion and femoro-tibial condylar motion patterns for 20 patients who had a traditional insert, 20 patients who had a constrained insert, and 10 previously published nonimplanted knees, all performing a deep knee bend activity while under fluoroscopic surveillance.
RESULTS: The results from this study indicate that subjects having a bicruciate stabilized TKA experienced similar postoperative kinematics for both constrained and unconstrained insert options, comparable to normal knees.
CONCLUSIONS: Subjects in this study having either a constrained or traditional insert experienced progressive rollback of both condyles, with the lateral condyle rolling more posterior than the medial condyle, leading to axial rotation. Although less in magnitude, these results were comparable to the normal knee in pattern, indicating that kinematic conflict did not occur for subjects having a constrained insert.
摘要：
背景：全膝关节置换术（TKA）中的约束插入件可能会提供额外的稳定性，但是这种插入件类型是否允许不受限制的运动，或者额外的整合会导致与凸轮/支柱机构在更深的屈曲中的运动学冲突？这项研究的目的是评估传统和约束双交叉稳定（BCS）TKA插入件的承重运动学，以确定凸轮/支柱机构引起的回滚是否与约束聚乙烯插入件一致。
方法：本研究使用先前发表的三维模型拟合技术，比较了20名传统插入物患者的负重屈曲和股胫骨髁运动模式，20名患者有一个限制性的插入，和10个以前发表的非植入膝盖，所有在透视监测下进行深膝关节弯曲活动。
结果：这项研究的结果表明，患有BCSTKA的受试者在受约束和不受约束的插入选项中都经历了相似的术后运动学，相当于正常的膝盖。
结论：本研究中受约束或传统插入的受试者经历了两个髁的渐进回滚，外髁比内髁更向后滚动，导致轴向旋转。虽然幅度较小，这些结果在模式上与正常膝关节相当，表明具有约束插入的受试者不会发生运动学冲突。
方法：本研究使用先前发表的三维模型拟合技术，比较了20名传统插入物患者的负重屈曲和股胫骨髁运动模式，20名患者有一个限制性的插入，和10个以前发表的非植入膝盖，所有在透视监测下进行深膝关节弯曲活动。
结果：这项研究的结果表明，患有BCSTKA的受试者在受约束和不受约束的插入选项中都经历了相似的术后运动学，相当于正常的膝盖。
结论：本研究中受约束或传统插入的受试者经历了两个髁的渐进回滚，外髁比内髁更向后滚动，导致轴向旋转。虽然幅度较小，这些结果在模式上与正常膝关节相当，表明具有约束插入的受试者不会发生运动学冲突。
