- 期刊
運動誘發疲勞對膝關節外翻角度與額狀面膝關節能量吸收之影響
Effect of Exercise-Induced Fatigue on Knee Valgus Angle and Frontal Plane Knee Joint Energy Absorption
摘要
異常的下肢關節力學和神經肌肉控制的改變增加運動員下肢傷害的風險，而前十字韌帶傷害機轉已被證實與生物力學因子有關。動態膝關節外翻為髖關節內收、髖關節內旋和膝關節外展的組合，被認為是非接觸性前十字韌帶損傷情況下常見的下肢對齊方式，著地時過大的膝關節外翻角度是導致前十字韌帶受傷的主因。運動引起的疲勞會導致肌肉骨骼損傷，並降低運動參與時間和身體能量效益。然過去針對運動誘發疲勞著地時對膝關節生物力學的研究結果尚無定論，且大部分研究聚焦於矢狀面關節活動面。本研究目的在探討運動誘發疲勞時執行側向切入動作對膝關節外翻角度與額狀面能量吸收之影響。招募12名大學運動員，以疲勞前及疲勞後兩種情境執行側向切入動作成功共3次。疲勞協定程序包括原地直膝垂直跳及疲勞自覺量表。以動力學逆過程方法計算下肢關節力矩、關節作功與關節功率。研究結果顯示：側向切入著地瞬間，疲勞後對膝關節外翻角度顯著增加；除外，髖關節最大角速度、垂直分力峰值、向後分力峰值、髖關節外展力矩及膝關節總作負功量等參數，運動誘發疲勞後皆顯著大於誘發疲勞前。本研究結論認為運動誘發疲勞後會顯著改變額狀面下肢生物力學表現，尤其是在膝關節能量吸收方面。較大的膝關節額狀面能量吸收可能會增加前十字韌帶負荷。因此，本研究建議在肌肉疲勞後應避免進行過度的額狀面切入動作以降低前十字韌帶損傷風險的可能性。
並列摘要
Abnormal lower extremity joint mechanics and altered neuromuscular control increase the risk of lower extremity injuries in athletes. The mechanism of anterior cruciate ligament (ACL) injury is associated with biomechanical factors. Dynamic knee valgus, which is recognized as a common lower extremity alignment in non-contact ACL injury situations, is the combination of hip adduction, hip internal rotation, and knee abduction movements. Excessive knee valgus angle during landings was one of the main factors for ACL injuries. Exercise-induced fatigue contributes to musculoskeletal injury, as well as reducing participation time and body energy efficiency during exercise. However, the effects of exercise-induced fatigue to the knee joint during landing have not been clearly established; most studies focus on the biomechanics of lower extremity in the sagittal plane. The purpose of the study was to determine the effects of exercise-induced fatigue on knee valgus angle and frontal plane lower extremity energy absorption during a side-cutting task. Twelve male collegiate athletes were recruited. Three successful trials of a side-cutting task were obtained during pre- and post-fatigue. The fatigue protocols included vertical jumping and rating of perceived exertion. The inverse dynamics method was used to calculate the joint moment, joint work, and joint power of lower extremity. Results indicated that the knee valgus angle, peak hip angular velocity, peak vertical ground reaction force, peak posterior force, hip abduction moment, and total knee negative work were significantly greater in post- than in pre-fatigue condition. We conclude that muscle fatigue might significantly alter the biomechanics of lower limbs in the frontal plane, especially in the knee energy absorption. Greater frontal-plane energy absorption in the knee joint during landing might increase the ACL loading. Therefore, this study suggests that athletes should avoid excessive frontal-plane cutting movements after muscle fatigue to decrease the risk of ACL injury.