Department of Orthopaedic Surgery, University Hospital RWTH Aachen, Aachen, Germany.
Chair of Medical Engineering, Helmholtz-Institute Aachen, RWTH Aachen University, Aachen, Germany.
Biomed Res Int. 2018 Apr 23;2018:7189714. doi: 10.1155/2018/7189714. eCollection 2018.
The purpose of this study was to evaluate the approach of using an electromagnetic tracking (EMT) system for measuring the effects of stepwise, simulated knee injuries on patellofemoral (PF) and tibiofemoral (TF) kinematics.
Three cadaver knees were placed in a motion rig. EMT sensors were mounted on the patella, the medial/lateral femoral epicondyles, the tibial condyle, and the tibial tuberosity (TT). After determining the motion of an intact knee, three injuries were simulated and the resulting bony motion was tracked.
Starting with the intact knee fully extended (0° flexion) and bending it to approximately 20°, the patella shifted slightly in the medial direction. Then, while bending the knee to the flexed position (90° flexion), the patella shifted progressively more laterally. After transecting the anterior cruciate ligament (ACL), the base of the medial menisci (MM) at the pars intermedia, and the medial collateral ligament (MCL), individual changes were observed. For example, the medial femoral epicondyle displayed a medial lift-off in all knees.
We demonstrated that our EMT approach is an acceptable method to accurately measure PF joint motion. This method could also enable visualization and in-depth analysis of in vivo patellar function in total knee arthroplasty, if it is established for routine clinical use.
本研究旨在评估使用电磁跟踪（EMT）系统测量逐步模拟膝关节损伤对髌股（PF）和胫股（TF）运动学影响的方法。
将三个尸体膝关节置于运动学装置中。EMT 传感器安装在髌骨、股骨内/外侧髁、胫骨髁和胫骨结节（TT）上。在确定了完整膝关节的运动后，模拟了三种损伤，跟踪了由此产生的骨骼运动。
从完全伸展（0°屈曲）的完整膝关节开始，弯曲至约 20°，髌骨轻微向内侧移位。然后，当膝关节弯曲至屈曲位置（90°屈曲）时，髌骨逐渐向外侧移位。在前交叉韧带（ACL）、中间部的内侧半月板（MM）基部和内侧副韧带（MCL）切断后，观察到了各个变化。例如，所有膝关节的内侧股骨髁都出现了内侧抬起。
我们证明了我们的 EMT 方法是一种准确测量 PF 关节运动的可接受方法。如果 EMT 方法被确立为常规临床应用，它还可以用于可视化和深入分析全膝关节置换术中的髌骨功能。
