Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
Clin Biomech (Bristol). 2022 Oct;99:105762. doi: 10.1016/j.clinbiomech.2022.105762. Epub 2022 Sep 9.
This study aimed to determine the kinematics of medial pivot total knee arthroplasty by comparing weight-bearing and non-weight-bearing deep knee bending and to evaluate the effect of the weight-bearing state on the kinematics.
The kinematics of 19 knees were investigated under fluoroscopy during squatting (weight-bearing) and active-assisted knee bending (non-weight-bearing) using two- to three-dimensional registration technique. Accordingly, range of motion, anteroposterior translation for the medial and lateral low contact points, axial rotation of the femoral component relative to the tibial component and kinematic pathway were evaluated.
There was no difference in range of motion between the two states. The medial anteroposterior translation showed no significant movement with no anterior translation in both the weight-bearing and non-weight-bearing from 0° to 90° of flexion. Regarding the lateral anteroposterior translation, a posterior translation was observed during weight-bearing, whereas a slight anterior translation from 0° to 30° of flexion and subsequent posterior translation were found in the non-weight-bearing. Femoral external rotation was observed in the weight-bearing, whereas femoral internal rotation was seen from 0° to 30° of flexion and subsequent femoral external rotation was observed in the non-weight-bearing. The kinematic pathway showed medial pivot motion and subsequent bicondylar rollback in the weight-bearing, whereas only medial pivot motion was observed in the non-weight-bearing.
The medial anteroposterior translation of the femur during deep knee bending showed no anterior motion in the two states. The lateral anteroposterior translation and femoral rotation were different in the mid-flexion range between the two states.
本研究旨在通过比较负重和非负重状态下的全膝关节置换术中的内侧枢轴屈膝动作，来确定内侧枢轴全膝关节置换术的运动学，并评估负重状态对运动学的影响。
采用二维到三维配准技术，在关节镜下研究了 19 例膝关节在深蹲（负重）和主动辅助屈膝（非负重）时的运动学。因此，评估了活动度、内外侧低接触点的前后平移、股骨相对于胫骨组件的轴向旋转以及运动学轨迹。
两种状态下的活动度没有差异。内侧前后平移在 0°至 90°的屈曲过程中没有明显运动，没有前向平移，在负重和非负重两种状态下均如此。至于外侧前后平移，在负重时观察到向后平移，而在非负重时，从 0°到 30°的屈曲过程中观察到轻微的向前平移，随后是向后平移。负重时观察到股骨外旋，而在 0°至 30°的屈曲过程中观察到股骨内旋，随后观察到股骨外旋。在负重时，运动学轨迹显示内侧枢轴运动，随后是双髁后退，而在非负重时仅观察到内侧枢轴运动。
在两种状态下，股骨在深度屈膝时的内侧前后平移都没有向前运动。在两种状态下，中屈曲范围的外侧前后平移和股骨旋转不同。
