探討一創新之肌內效貼紮方法對下肢動態膝外翻於疲勞時期單腳落地與單腳蹲任務之影響

Abstract

背景: 動態膝外翻常用來描述動態任務中下肢的姿勢，髖、膝與踝關節於動態承重任務時為一閉鎖動力鍊，當出現較大之髖關節內收、內轉與膝關節外展動作時會導致動態膝外翻增加，過度動態膝外翻被認為與髕骨股骨疼痛症候群、髂脛束症候群與前十字韌帶損傷等膝關節傷害有關，而不足的髖關節肌肉力量與不正確之神經肌肉控制策略被認為是造成過度動態膝外翻的原因。相較於雙腳承重任務，單腳承重任務如單腳落地或單腳蹲等，較易出現較大之膝外翻角度或力矩，過去文獻也指出疲勞會增加肌肉的需求、改變神經肌肉控制策略並增加動態膝外翻，因此疲勞時期之單腳承重任務被認為有較高之膝關節傷害的風險。利用髖關節肌肉之肌力訓練與神經肌肉控制訓練能降低過度動態膝外翻的發生，但此兩種介入方式至少需要經過四至八周的訓練時間，且過去文獻無探討其於疲勞狀態下對於降低動態膝外翻的影響，因此，目前仍缺乏一有立即效果並且能於疲勞狀態下仍能避免過度動態膝外翻的介入方式。抗膝外翻貼紮為一創新之肌內效貼紮方式，於臨床被用於預防過度膝外翻的發生，但目前缺乏生物力學之實證。 目的: 探討一創新之肌內效貼紮方式(抗膝外翻貼紮)於疲勞時期單腳落地與單腳蹲之生物力學參數的影響。 方法: 本實驗共徵召十八名健康且有規律運動習慣之女性受試者，本實驗將會使用動作捕捉系統、力板與無線肌電圖紀錄關節動作、地面反作用力與臀大肌、臀中肌、股外側肌及股二頭肌之肌肉活化程度。受試者會以隨機順序接受貼有抗膝外翻貼紮與未貼抗膝外翻貼紮兩種貼紮狀況，分別於疲勞前與疲勞後進行連續三次之單腳落地與單腳蹲測試，完成疲勞前測試後，受試者會被要求反覆執行疲勞活動直至最大垂直跳躍高度下降20%並立即執行疲勞後測試。結果量測包含關節角度、關節力矩、達到穩定所需時間、於單腳落地與單腳蹲之下降與上升時期的最大與平均肌肉活化程度。 結果：在疲勞的狀況下，受試者在單腳落地瞬間有較大的髖內轉角度、較小的髖關節內轉的改變值，最大的膝關節屈曲、軀幹彎曲與往落地腳同側側彎的角度都有顯著增加。（落地瞬間髖內轉角度，p<0.001；髖內轉改變值，p<0.001；膝屈曲，p=0.034；軀幹彎曲，p=0.044；軀幹同側側彎，p=0.031）單腳落地時最大膝關節內收力矩在經過疲勞之後顯著下降（p=0.01），臀大肌、臀中肌、股外側肌與股二頭肌的最大與平均肌肉收縮程度皆顯著上升。受試者在接受抗膝外翻貼紮的情況下，其於單腳落地時的髖內收、髖內轉角度、膝外展的角度及力矩都有顯著減少（髖內收，p=0.004；髖內轉，p=0.008；膝外展角度，p=0.031；膝外展力矩，p=0.02），且落地過程中臀中肌與股外側肌的最大與平均肌肉活化程度也較低，重複量測雙因子變異數分析於下肢動作及肌肉收縮程度並未顯示疲勞與貼紮的交互作用。達到穩定所需時間在前後方向與內外方向於疲勞之後皆顯著上升 (前後方向，p=0.009；內外方向，p=0.031），而貼紮對於落地後達到穩定所需的時間並沒有顯著影響。 結論：疲勞影響單腳落地時的下肢與軀幹動作、姿勢穩定能力與肌肉活化程度，抗膝外翻貼紮於單腳落地時避免過度動態膝外翻發生並減少肌肉收縮程度，抗膝外翻貼紮效果為立即性且在疲勞狀態下仍具有效果。

Background: Excessive dynamic knee valgus is a commonly seen lower extremity malalignment associated with many sports injuries, such as patellofemoral pain syndrome, iliotibial band syndrome and anterior cruciate ligament injuries. Excessive dynamic knee valgus was consisted of greater hip adduction, hip internal rotation and knee abduction during dynamic weight bearing tasks. Insufficient hip muscle strength and/or abnormal neuromuscular control may contribute to excessive knee valgus. Greater knee valgus angles and moments were observed during single-leg landing, and it was considered at higher risk of knee injuries when compared to double-leg landing. Previous studies reported that fatigue will further increase muscle demands, alter neuromuscular control and increase knee valgus. Hip muscle strengthening and neuromuscular control training are proved to be beneficial in decreasing excessive knee valgus, however, it will take at least 4 to 8 weeks to complete these two training regimes. A immediately effective and fatigue-resistant protocol to prevent excessive knee valgus is still lacking. A novel kinesio taping technique (anti-valgus taping) has been used to prevent excessive dynamic knee valgus in clinical practice, however, the efficacy of anti-valgus taping has not been examined with biomechanical evaluations to date. Purpose: The purpose of this study was to investigate the effect of a novel kinesio taping technique (anti-valgus taping) on lower extremity biomechanical parameters during single-leg landing and squatting under the influence of fatigue. Methods: 18 healthy female participants with regular exercise habit were recruited in this study. Vicon motion capture system with 8 infra-red cameras, an AMTI force plate and wireless EMG system were used to collect joint movements, GRF and gluteus maximus and medius, vastus lateralis and biceps femoris muscle activities. Two taping conditions were tested: with and without anti-valgus taping. Subjects performed three consecutive single-leg landing and squatting tests before and after fatigue in both taping conditions. After the pre-fatigue session, subjects were asked to perform and repeat the fatigue protocol until reaching a reduction of 20 % maximal vertical jump height. Outcome measures including: joint angles and moments, time to stabilization, peak and average EMG amplitudes during descending and ascending phase of single-leg landing and squatting. Two-way repeated measures ANOVAs (taping X fatigue) were used to compare outcome variables in single-leg landing and squatting respectively with and without anti-valgus taping, before and after fatigue. Results: After fatigue, participants landed with greater hip internal rotation at initial contact, lesser hip rotation excursion, greater peak knee flexion, trunk flexion and ipsilateral lean angles. (hip IR at IC, p<0.001; hip rotation excursion, p<0.001; knee flexion, p=0.034; trunk flexion, p=0.044; trunk ipsilateral lean, p=0.031) There were lower peak knee adduction moments after fatigue in single-leg landing. (p=0.01) EMG amplitudes of Gmax, Gmed, VL and BF increased at peak and average in the fatigue condition. With anti-valgus taping, participants landed with less hip adduction, internal rotation, knee abduction angles and moments (hip ADD angles, p=0.004; hip IR angles, p=0.008; knee ABD angles, p=0.031; knee ABD moment, p=0.02). There were lower Gmed and VL EMG amplitudes at peak and in descending phase with taping. Two-way repeated measures ANOVA revealed that there were no interactions between fatigue and taping on lower extremity movements and muscle activations. Time to stabilization (TTS) in both AP and ML direction increased after fatigue, but there were no differences in TTS between taping conditions. (main effect of fatigue: AP, p=0.009; ML, p=0.031) Conclusion: Fatigue influenced landing movements, postural stability and muscle activations. Anti-valgus taping reduced dynamic knee valgus and muscle activations during single-leg landing. The effects of anti-valgus taping on preventing excessive knee valgus were immediate and fatigue-resistant.