老年人六分鐘行走測試與下肢神經肌肉系統之相關性-膝關節本體感覺、單腳站立平衡、踝關節肌力、膝關節肌力及耐力

Abstract

背景及目的：過去六分鐘行走測試使用在心肺疾病患者心肺功能相關參數之評估，其具有良好的信度及效度。近年來亦使用在週邊血管疾病、神經系統疾病及老年人的有氧能力測試，更有學者用來評估下肢骨骼肌肉系統疾病患者，如退化性膝關節炎、人工膝關節或髖關節置患術後的治療成效。近年來有部分學者探討可能影響六分鐘行走距離的因素尚包括神經肌肉系統及骨骼系統，如肌力、平衡能力等參數，但相關的研究有限，且尚未有較完整而明確的定論。為探討六分鐘行走測試與神經肌肉系統的相關性，以六十五歲以上老人為對象，研究六分鐘行走距離與其膝關節本體感覺、平衡能力、下肢肌力、耐力的相關性，以期了解六分鐘行走測試之結果，於上述各因子中的代表性有多少？是運動控制能力居重？感覺能力居重？還是兩者兼併？希望藉以證實六分鐘行走測試結果與上述各神經肌肉系統因子的相關性，以利於此測試在臨床上評估及治療病人之應用。方法：本研究徵召90名六十五歲以上能獨立完成日常生活功能，並可不使用輔具獨立行走三十分鐘以上，沒有心肺系統、神經系統病變等疾病診斷及症狀之老年人。測試步驟及流程包含基本資料之收集、膝關節本體感覺（閉鎖鏈主動－主動膝關節角度配對誤差測試）、六分鐘行走測試、站姿平衡測試(睜眼、閉眼三十秒單腳站立平衡)、踝關節等速肌力測試（60°/秒、120°/秒）、膝關節等速肌力測試（60°/秒、120°/秒、180°/秒）、角速度180°/秒時之膝關節耐力的評估，每一個測試之間休息五分鐘。比較六分鐘行走測試總距離與人體測量學中各參數的相關性，及六分鐘行走測試總距離與神經肌肉系統參數，包括膝關節本體感覺、單腳站立平衡、踝關節肌力、膝關節肌力及耐力之相關性；並分析上述因子對六分鐘行走測試結果何者影響較大。結果：人體測量學部分，只有身高及年齡與六分鐘行走距離有低到中等程度的相關性（r=0.34-0.45，p=0.001），而睜眼及閉眼單腳站立平衡（r=0.52-0.60，p=0.001）及下肢肌力中踝關節（r=0.39-0.57，p＜0.001）與膝關節（r=0. 54-0.59，p=0.001）之肌力亦與六分鐘行走距離呈中等程度的相關性，其中睜眼單腳站立平衡比閉眼單腳站立平衡與六分鐘行走距離之相關性高，下肢肌力中的膝屈肌群相較於其他肌群又有更顯著的相關性。結論：六分鐘行走距離與平衡表現及下肢肌力有關，尤其是膝屈肌及睜眼單腳站立平衡能力的相關性較高。

Background and purpose: The 6-minute walk test had been used to assess the functional capacity in patients with cardiopulmonary disorders. Recently, the 6-minute walk test has popularly been used as a simple tool to evaluate patients’ aerobic capacity in patients with peripheral vascular disease, neurological disease, and musculoskeletal disorders. However, few literatures report the correlation between the 6-minute walk distance and commonly evaluated variables, such as muscle strength, endurance, standing balance…etc., as we assess patients with musculoskeletal disorders. The purpose of this study, therefore, is to investigate the correlations between the 6-minute walk distance and neuromuscular parameters, including knee proprioception (joint position sense), standing balance, and muscle function (including muscle strength and muscle endurance). Methods: 90 elderly volunteers were recruited. They are greater than 65 years old without any walking, cardiopulmonary or neurological disorders. All of them received the following assessments: knee reposition sense by closed chain in active-active test mode; one leg standing balance test (open and close eyes for 30 seconds); ankle muscle torque of dorsi-flexor and plantar flexor at 30º/s and 120º/s angular velocities; knee muscle torque of extensor and flexor at 60º/s,120º/s and 180º/s angular velocities; and knee muscle endurance at 180º/s, in addition to 6-minute walk test. Results: The correlation (r value) between the 6-minute walk distance and age, height, one leg standing balance, ankle muscle torque and knee muscle torque was to be -0.45, 0.34, 0.52-0.60, 0.39-0.57, and 0.54-0.59, respectively. The one leg standing balance with open eyes and knee flexor muscle torque showed greater correlation with the 6-minute walk distance than other variables. Conclusion: The 6-minute walk distance is probably one of assessment tools for the standing balance and knee flexor torque in the elderly subjects.