Kono Kenichi, Inui Hiroshi, Tomita Tetsuya, Yamazaki Takaharu, Taketomi Shuji, Yamagami Ryota, Kawaguchi Kohei, Sugamoto Kazuomi, Tanaka Sakae
Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Department of Orthopaedic Biomaterial Science, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan.
Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Knee. 2020 Jun;27(3):878-883. doi: 10.1016/j.knee.2020.03.002. Epub 2020 Apr 13.
Many patients who undergo unicompartmental knee arthroplasty (UKA) have an expectation that their knee flexion would increase following its replacement. Additionally, the survival rate of mobile-bearing UKA (MB-UKA) is high. However, the effect on the patient's kinematics remains unknown. This study aimed to clarify the kinematic effect of MB-UKA knees during high-flexion activities by comparing the in vivo kinematics before and after surgery.
A squatting motion was performed under fluoroscopic surveillance in the sagittal plane before and after MB-UKA. To estimate the spatial position and orientation of the knee, a two-dimensional/three-dimensional registration technique was used. The femoral rotation and varus-valgus angle relative to the tibia and anteroposterior (AP) translation of the medial and lateral side of the femur on the plane perpendicular to the tibial mechanical axis in each flexion angle were evaluated.
Regarding the varus-valgus angle, the preoperative knees indicated a significant varus alignment compared with the postoperative knees from 10° to 60° of flexion. There were no significant differences in the femoral rotation angle, AP translation, and kinematic pathway before and after MB-UKA in the mid-flexion of the range of motion.
There were differences between the varus-valgus knee kinematics before and after MB-UKA, from 10 to 60° of flexion, but no difference from midrange of flexion to deep flexion. In addition, the rotational knee kinematics before and after MB-UKA was not significantly different.
许多接受单髁膝关节置换术（UKA）的患者期望置换后膝关节屈曲度会增加。此外，活动平台单髁膝关节置换术（MB-UKA）的生存率很高。然而，其对患者运动学的影响仍不清楚。本研究旨在通过比较手术前后的体内运动学，阐明MB-UKA膝关节在高屈曲活动中的运动学效应。
在MB-UKA手术前后，于荧光透视监测下在矢状面进行蹲踞动作。为估计膝关节的空间位置和方向，采用二维/三维配准技术。评估每个屈曲角度下股骨相对于胫骨的旋转、内翻-外翻角度以及在垂直于胫骨机械轴的平面上股骨内外侧的前后（AP）平移。
关于内翻-外翻角度，术前膝关节在屈曲10°至60°时与术后膝关节相比显示出明显的内翻对线。在运动范围的中屈曲阶段，MB-UKA手术前后的股骨旋转角度、AP平移和运动路径无显著差异。
MB-UKA手术前后，在屈曲10°至60°时膝关节的内翻-外翻运动学存在差异，但在中屈曲至深度屈曲时无差异。此外，MB-UKA手术前后膝关节的旋转运动学无显著差异。
