手拇指腕掌關節退化性關節炎對於上肢疾病中重要議題之一，然而從臨床結果顯示，針對此關節的多樣治療方法仍有許多不適處。最大主因為現今對於手拇指腕掌關節生物力學特性沒有明確瞭解，所以本篇實驗目的要探討手拇指腕掌關節的基本接觸特性。
本研究提出大體實驗去探討手拇指腕掌關節在不同受力模組的接觸機械性質，實驗內容包含給予每一條影響腕掌關節的肌腱做不同的力量附載以及模擬大體做功能性捏力動作，從電腦斷層影像去取得拇指腕掌關節在力量負載下的骨頭幾何模型，再以此三維模型去計算在不同力量附載下拇指腕掌關節的接觸性質以及旋轉位移量化描述關節特性。
本篇結果顯示手拇指掌側肌腱造成腕掌關節接觸在掌側以及掌骨較小的位移量相反的背側肌腱則形成背側接觸以及較大的位移量。而在捏力實驗結果顯示，腕掌關節接觸在掌骨上的橈骨後側 (dorsal-radial) 區域，此為較不穩定的接觸情況。

The osteoarthritis (OA) of thumb carpometacarpal (CMC) joint is a critical disease in upper extremity. However, up to now, the clinical outcomes of various treatments for OA especially in thumb CMC joint were unsatisfactory. The insufficient knowledge of biomechanics for thumb CMC joint is one of main factors. Therefore, the purpose of this study is to investigate basic contact modes of thumb CMC joint.
The study used cadaveric experiments to investigate contact mechanics of thumb CMC joint with two loading modes including: loading the tendon individually and the simulation of lateral pinch function posture. The position of trapezium and metacarpal of CMC joint under loading were obtained from CT image. Three-dimensional biomechanical model was developed to calculate the motion pattern, translation and rotation of CMC joint under various loadings.
The results showed that palmar tendons (FPL, APB, and ADD) caused contact on palmar region with smaller displacement while dorsal tendons (EPL and APL) resulted in contact region on dorsal region with larger displacement. In lateral pinch, the main contact was on dorsal-radial region of trapezium which might indicate an unstable condition.

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