動作分析於音樂傷害之應用－－以大提琴學生演奏顫音時左上肢動作分析為例

Application of Motion Analysis to Studying Injury of Cello Students Playing Vibration-Sound

大提琴之顫音在技巧上經常被使用，且是每位學生每天都需練習；運用得當，可使音樂有感情；運用不當，不僅音色受損且使得學習者肌肉受傷，甚而斷送了音樂生涯。演奏顫音時，手指顫抖速度非常快，老師的示範，學生往往不得其門而入，以往有些學者以錄影機為工具，但所得資料僅影像形態，無法確切分析其手指振動頻率及手肘穩定度。手指振幅與手肘穩定度會影響音色，如振幅不一致，表示手指過於緊張，且協調不良；手肘之穩定度不夠，則可能影響肩部肌肉之緊張度及音色。今以電腦化三度空間動作分析儀，攝得資料，分析其顫音之手指振動頻率，手肘的穩定度， 以此資料作學生學琴技巧之參考及肌肉緊張度之分析，進而改進演奏者之姿勢，不僅減少音樂傷害且可增進音色。本研究個案對象為大提琴學生二十名，以電腦化動作分析儀分析大提琴學生於演奏顫音時，分析左手指的振動振幅及左手肘之穩定度，另以生物迴饋儀測量左肩肌肉之緊張度，以了解彼此之間之關係。統計方式以相關係數分析求出手肘穩定度與手指之頻率穩定度與左肩肌肉之緊張度彼此之關係，另以T test作學習五年以上及五年以下同年級學生分析，分析其手指振輻穩定度，左手肘穩定度及左肩部肌肉緊張度，求其學習時間長短之兩組有無統計學上意義之差異。兩組於左肩部肌肉之緊張度，並無統計學上之意義差別；但於頻率穩定度及左手肘穩定度，則有明顯差異且具統計學上意義，（P < 0.05）。另外相關係數分析得知手指振幅穩定度與左肘穩定度具統計學意義之相關（p < 0.05），左肩肌肉緊張度與振幅穩定度及左肘穩定度均無相關。本研究結果顯示學琴時間之長短，可影響技巧之表現，如手指振幅之穩定度及手肘穩定度則有顯著之差異。但於肩部肌肉緊張度，則並不因為學琴時間之長短而有顯著差異。由相關性分析得知手肘穩定度與手指振幅穩定度有統計學上意義之相關，由此得知一般老師在教導學生時常可藉由觀察肘度穩定度來促使學生顫音頻率穩定度增加，進而使音色表現得更好，在演奏中正確的姿勢不僅可減少音樂傷害也可增加琴藝。於統計得知，肌肉緊張度與肘度穩定度及振幅穩定度並無相關，此可能由於振幅穩定度及手肘穩定度較屬於技巧性，而肌肉緊張度除受姿勢影響外，亦受心理層面影響。動作分析儀比錄影機更能提供許多訊息，讓老師與學生都能體會姿勢有何不良之處，應如何校正，也可與老師之正確姿勢作一比較，可發現學生問題所在，再比較其主訴病痛，可推論其受傷之原因，進而減少音樂傷害的產生。

Cellists often employ the technique of playing vibration-sound, which influences the sound quality of string performance. The left hand does more finely coordinated and repetitive actions with the fingers, requiring equal amount of tension of the arm during playing. Left hand and arm problems are more commonly seen in younger cello players.We use three-dimensional motor analysis and biofeedback equipment to evaluate the technique of playing vibration-sound. Twenty cello students were enrolled and divided into two groups according to their grade and years of training. ≧5 years and <5 years) Data of wavelength of finger vibration, elbow stability and shoulder muscle intensity were collected. Statistical analysis by student-t test and correlation analysis showed no difference in shoulder muscle intensity between the two groups. There were statistical differene in wavelength of finger vibration and elbow stability (p＜0.05). The result of correlation analysis revealed strong correlation between left elbow stability and finger vibration wavelength. There was no correlation between shoulder intensity, elbow stability, finger vibration wavelength. This study showed that shoulder problems are mechanical in nature, resulting from different causes. The most frequent of which were excessive playing and poor posture, over practicing, using excessive tension in any of the involved muscle groups. The vibration wavelength of finger is that main factor of vibration quality. We can observe the elbow stability instead of inspecting vibration wavelength of the fingers. Three-dimensional motion analysis is better than video in teaching program of music students. It can provide scientific data for evaluating the posture, joint stability and joint speed of a musician during performance, which can shed light on the mechanism of musician's injury.