Labbé David R, Li Di, Grimard Guy, de Guise Jacques A, Hagemeister Nicola
Laboratoire de recherche en imagerie et orthopédie (LIO), Centre de recherche du Centre hospitalier de l'Université de Montréal (CHUM), Tour Viger, 900, rue Saint-Denis, Local R11.326, Montreal, QC, H2X 0A9, Canada.
École de technologie supérieure, Montreal, Canada.
Knee Surg Sports Traumatol Arthrosc. 2015 Aug;23(8):2330-2338. doi: 10.1007/s00167-014-3056-8. Epub 2014 May 15.
The purpose of the study was to demonstrate the feasibility of a new measurement system using micro-electromechanical systems (MEMS)-based sensors for quantifying the pivot shift phenomenon.
The pivot shift test was performed on 13 consecutive anterior cruciate ligament-deficient subjects by an experienced examiner while femur and tibia kinematics were recorded using two inertial sensors each composed of an accelerometer, gyroscope and magnetometer. The gravitational component of the acquired data was removed using a novel method for estimating sensor orientations. Correlation between the clinical pivot shift grade and acceleration and velocity parameters was measured using Spearman's rank correlation coefficients.
The pivot shift phenomenon was best characterized as a drop in femoral acceleration observed at the time of reduction. The correlation between the femoral acceleration drop and the clinical grade was shown to be very strong (r = 0.84, p < 0.0001).
The present study demonstrates the feasibility of quantifying the pivot shift using MEMS-based sensors and removing the gravitational component of acceleration using an estimation of sensor orientation for improved correlation to the clinical grade.
本研究的目的是证明一种使用基于微机电系统（MEMS）的传感器来量化轴移现象的新测量系统的可行性。
由一名经验丰富的检查者对13名连续的前交叉韧带损伤患者进行轴移试验，同时使用两个惯性传感器记录股骨和胫骨的运动学数据，每个传感器由一个加速度计、陀螺仪和磁力计组成。使用一种估计传感器方向的新方法去除采集数据中的重力分量。使用Spearman等级相关系数测量临床轴移分级与加速度和速度参数之间的相关性。
轴移现象的最佳特征是复位时观察到的股骨加速度下降。股骨加速度下降与临床分级之间的相关性非常强（r = 0.84，p < 0.0001）。
本研究证明了使用基于MEMS的传感器量化轴移以及通过估计传感器方向去除加速度的重力分量以改善与临床分级相关性的可行性。
