Li Guoan, Zhou Chaochao, Li Sophia, Yu Jia, Foster Timothy, Bedair Hany
Orthopaedic Bioengineering Research Center, Newton-Wellesley Hospital/Massachusetts General Brigham, 159 Wells Avenue, Newton, MA, 02459, USA.
Department of Orthopaedics, Massachusetts General Hospital, Boston, MA, USA.
Knee Surg Relat Res. 2024 May 24;36(1):20. doi: 10.1186/s43019-024-00224-7.
Numerous research has reported that total knee arthroplasty (TKA) cannot reproduce axial tibial rotations of normal knees. The objective of this study was to measure the tibiofemoral articular contact motions and axial tibial rotations of TKA knees to investigate the mechanism causing the knee kinematics change of after TKAs.
Eleven patients with unilateral cruciate retaining (CR) TKA were tested for measurements of knee motion during a weight-bearing flexion from 0° to 105° using an imaging technique. The tibiofemoral contact kinematics were determined using the contact points on medial and lateral surfaces of the tibia and femoral condyles. Axial tibial rotations were calculated using the differences between the medial and lateral articulation distances on the femoral condyles and tibial surfaces at each flexion interval of 15°.
On femoral condyles, articular contact distances are consistently longer on the medial than on the lateral sides (p < 0.05) up to 60° of flexion, corresponding to internal tibial rotations (e.g., 1.3° ± 1.0° at 15-30° interval). On tibial surfaces, the articular contact point on the medial side moved more posteriorly than on the lateral side at low flexion angles, corresponding to external tibial rotations (e.g., -1.4° ± 1.8° at 15-30° interval); and more anteriorly than on the lateral sides at mid-range flexion, corresponding to internal tibial rotations (e.g., 0.8° ± 1.7° at 45-60° interval). At higher flexion, articular motions on both femoral condyles and tibial surfaces caused minimal changes in tibial rotations.
These results indicate that the axial tibial rotations of these TKA knees were mainly attributed to asymmetric articulations on the medial and lateral femoral condyles and tibial surfaces. The data can help understand the mechanisms causing axial tibial rotations of TKA knees and help improve implant designs for restoration of normal knee kinematics.
大量研究报告称，全膝关节置换术（TKA）无法重现正常膝关节的轴向胫骨旋转。本研究的目的是测量TKA膝关节的胫股关节接触运动和轴向胫骨旋转，以研究TKA术后膝关节运动学变化的机制。
使用成像技术对11例单侧保留交叉韧带（CR）的TKA患者进行测试，测量其在0°至105°负重屈曲过程中的膝关节运动。通过胫骨和股骨髁内外侧表面的接触点确定胫股关节接触运动学。在15°的每个屈曲间隔处，利用股骨髁和胫骨表面内外侧关节距离的差异计算轴向胫骨旋转。
在股骨髁上，直至60°屈曲时，内侧关节接触距离始终比外侧长（p < 0.05），这与胫骨内旋相对应（例如，在15 - 30°间隔时为1.3°±1.0°）。在胫骨表面，低屈曲角度时内侧关节接触点比外侧更向后移动，这与胫骨外旋相对应（例如，在15 - 30°间隔时为 - 1.4°±1.8°）；在中等屈曲范围时，内侧比外侧更向前移动，这与胫骨内旋相对应（例如，在45 - 60°间隔时为0.8°±1.7°）。在更高屈曲角度时，股骨髁和胫骨表面的关节运动导致胫骨旋转变化最小。
这些结果表明，这些TKA膝关节的轴向胫骨旋转主要归因于股骨髁和胫骨表面内外侧的不对称关节。这些数据有助于理解TKA膝关节轴向胫骨旋转的机制，并有助于改进植入物设计以恢复正常膝关节运动学。
