青少年為手部受傷的主要族群，原因多源自於運動及職業傷害，受傷部位多以手指區域損傷為主。常見手部損傷的治療方式為支架固定和長時間的靜養，手術多為重度損傷者所需，因此評估靜養後患部的功能性和恢復程度對於治療者、患者而言皆有一定必要性。傳統進行評估的方式不外乎為實際動作測試，請求患者進行特定動作的同時進行觀察各項表現例如力量大小、動作範圍、持續時間等。
肌腱為手部受傷的主要部位，該損傷對手的功能性有著直接的影響。超音波彈性影像為一種廣泛用於測量軟組織機械特性的工具，在肌腱上亦有相關運用。相關研究已經將彈性影像用於測量運動狀態下的性能評估，觀察的目標多為較大的肌腱組織和易於測量的肌肉組織，在人體中相對細小的肌腱組織則較少討論。
為了瞭解手部肌腱在不同運動情況下的機械特性，此研究將使用高頻超音波彈性影像測量手指伸肌腱於手背的部分之性質於不同運動狀態下性質表現和使用外部震盪器產生低頻組織震動和高頻超音波換能器與超快速超音波成像系統來測量受試者進行手指伸展和手指彎曲時不同力道下手指伸肌腱的機械性質變化。另外將對豬隻後腿肌腱使用同樣測量方式在其進行拉伸測試時測量其機械性質的變化，以作為其動作性質的參考。實驗結果顯示人類手指在進行兩種不同的動作時，施力大小與其剪力波行進速度呈現性關係，又以手指彎曲的整體表現較為優秀且與動物實驗結果較為相似。動物實驗中的剪力波波速和肌腱的應力大小也有相同結果。此研究結果可以做為一般人進行該動作的超音波表現數據，作為病人在復健過程中恢復程度的參考指標。

Hand injuries mostly occur in youth group, usually resulted from exercise and working. The treatments of hand injury are usually the long-term rest with the fixation by splint except some acute injuries. To understand the effectiveness of therapy, evaluation of the hand functionality after resting is essential to the patient and therapist. Traditional way to evaluate the performance of the hand after injury is the motion test, patients perform a specific hand gesture to evaluate its performance like force value, range of motion, force duration etc.
Ultrasound elastography has been a reliable way to acquire the mechanical property of soft tissue, so are tendons. Previous researches have been utilized this technique to access tissue properties in different statements of movement. However, these tissues are the muscle and tendon with larger thickness in human, less topics are focus on small tendon.
Our study used high frequency ultrasound transducer and high frame rate ultrasound system to measure the shear wave velocity of the human digital extensor tendon in different movements and force value. Two movements of human finger are extension and flexion. We also measured the shear wave speed of porcine tendons during their tensile test as the reference of human test. External vibrator generated low frequency tissue vibration caused shear wave on the extensor tendon of human and the digital flexor tendon of porcine in our study. Results showed the linear relationship between the shear wave speed and stress of the tendon in animal test and the stress from loadcell reading in human test and animal experiment. The human result of finger flexion has less dispersion in data distribution and more likely to the animal result than finger extension. These results can be a reference to the patients for rehabilitation.

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