功能性電刺激應用於膝關節前十字韌帶之復健

Abstract

運動傷害常見之前十字韌帶斷裂會造成股四頭肌萎縮以及膝關節活動不穩定等情形。為避免患者在進行股四頭肌等速肌力訓練時產生脛骨前移的現象，本研究開發一套結合功能性電刺激之回授系統用以取代制式防脛骨前移裝置，以解決先前相關訓練效果不彰的現象。該回授系統之工作原理係利用等速肌力訓練儀所提供之角度、角速度、及力矩等信號做為膝關節屈肌電刺激強度與模式之根據，藉由屈肌適度的收縮以補償伸展時前十字韌帶的拉扯進而防止脛骨前移，以提高伸肌自主運動之復健訓練效果。 透過自行開發之側錄攝影裝置可觀察到受試者於股四頭肌等速肌力訓練時，使用功能性電刺激不但可達到與制式防脛骨前移裝置相似之防脛骨前移功效，且能改善先前膝關節活動範圍受限及力矩平順度減少的現象。此一系統將有助於運動員在受到類似傷害後能以最有效的復健方式提早回復到受傷前的最佳狀態。

Rupture of anterior cruciate ligament (ACL) in knee is a common sports injury which may cause knee instability and quadriceps atrophy. In order to prevent anterior translation of the tibia during isokinetic training exercises of the quadriceps, a feedback system incorporating functional electrical stimulation (FES) is implemented to replace conventional anti-shear devices. The feedback system modulates FES parameters according to angle position, angle velocity, and torque signals acquired from the isokinetic dynamometer system to induce moderate contractions of the hamstrings to compensate ACL dysfunction and to avoid anterior translation of the tibia during voluntary exercises of the quadriceps. The restriction of tibial anterior translation induced by the feedback system is confirmed by image processing techniques of captured knee joint images during quadriceps contractions, while better results in terms of range of motion and smoothness of torque curves were measured as compared to the conventional device. This new FES system will accelerate functional recovery of quadriceps in athletes who suffer from rupture of ACL by facilitating more efficient rehabilitation exercises of their quadriceps muscles.