Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.
J Knee Surg. 2022 Jul;35(8):828-837. doi: 10.1055/s-0040-1718681. Epub 2020 Oct 27.
The preservation of the posterior cruciate ligament in cruciate retaining (CR) total knee arthroplasty (TKA) designs has the potential to restore healthy knee biomechanics; however, concerns related to kinematic asymmetries during functional activities still exist in unilateral TKA patients. As there is a limited data available regarding the ability of the contemporary CR TKA design with concave medial and convex lateral tibial polyethylene bearing components to restore healthy knee biomechanics, this study aimed to investigate in vivo three-dimensional knee kinematics in CR TKA patients during strenuous knee flexion activities and gait. Using a combined computer tomography and dual fluoroscopic imaging system approach, in vivo kinematics of 15 unilateral CR TKA patients (comparison of replaced and contralateral nonreplaced knee) were evaluated during sit-to-stand, step-ups, single-leg deep lunge, and level walking. The patient cohort was followed-up at an average of 24.5 months ( ± 12.6, range 13-42) from surgical procedure. Significantly smaller internal knee rotation angles were observed for the contemporary CR TKA design during step-ups (2.6 ± 5.8 vs. 6.3 ± 6.6 degrees, < 0.05) and gait (0.6 ± 4.6 vs. 6.3 ± 6.8 degrees, < 0.05). Significantly larger proximal and anterior femoral translations were measured during sit-to-stand (34.7 ± 4.5 vs. 29.9 ± 3.1 mm, < 0.05; -2.5 ± 2.9 vs. -8.1 ± 4.4 mm, < 0.05) and step-ups (34.1 ± 4.5 vs. 30.8 ± 2.9 mm, < 0.05; 2.2 ± 3.2 vs. -3.5 ± 4.5 mm, < 0.05). Significantly smaller ranges of varus/valgus and internal/external rotation range of motion were observed for CR TKA, when compared with the nonoperated nee, during strenuous activities and gait. The preservation of the posterior cruciate ligament in the contemporary asymmetric bearing geometry CR TKA design with concave medial and convex lateral tibial polyethylene bearing components has the potential to restore healthy knee biomechanics; however, the study findings demonstrate that native knee kinematics were not fully restored in patients with unilateral asymmetric tibial polyethylene bearing geometry CR TKA during functional activities.
保留交叉韧带在保留交叉韧带（CR）全膝关节置换术（TKA）设计中有可能恢复健康的膝关节生物力学；然而，在单侧 TKA 患者中，功能活动期间的运动学不对称仍然存在相关问题。由于关于具有凹面内侧和凸面外侧胫骨聚乙烯衬垫组件的现代 CR TKA 设计恢复健康膝关节生物力学的能力的数据有限，因此本研究旨在研究剧烈膝关节弯曲活动和步态期间 CR TKA 患者的体内三维膝关节运动学。使用计算机断层扫描和双荧光透视成像系统的组合方法，对 15 例单侧 CR TKA 患者（比较置换和未置换的对侧膝关节）在从手术开始平均 24.5 个月（±12.6，范围 13-42）的时间内进行了评估坐站，步上，单腿深蹲和水平行走。在步上（2.6±5.8 vs. 6.3±6.6 度， < 0.05）和步态（0.6±4.6 vs. 6.3±6.8 度， < 0.05）期间，对于现代 CR TKA 设计，观察到较小的内部膝关节旋转角度。在坐站（34.7±4.5 vs. 29.9±3.1 mm， < 0.05；-2.5±2.9 vs. -8.1±4.4 mm， < 0.05）和步上（34.1±4.5 vs. 30.8±2.9 mm， < 0.05；2.2±3.2 vs. -3.5±4.5 mm， < 0.05）期间，测量到较大的近端和前股骨平移。与非手术的膝盖相比，在剧烈运动和步态中，CR TKA 的内翻/外翻和内/外旋转运动范围明显较小。在具有凹面内侧和凸面外侧胫骨聚乙烯衬垫组件的现代非对称承载体几何形状 CR TKA 设计中保留后交叉韧带有可能恢复健康的膝关节生物力学；然而，研究结果表明，在功能活动期间，单侧非对称胫骨聚乙烯衬垫几何形状 CR TKA 的患者并未完全恢复自然膝关节运动学。
