舟狀骨是最容易發生骨折的腕骨，而其骨折引起的併發症大多都相當嚴重而且難以處理，大部份文獻所統計的主要受傷機制是”摔倒後撞擊外展的手腕”，然而其中的力學機制卻還沒有很明確的瞭解，因此本研究將針對這種情況，探討舟狀骨與周圍腕骨間的接觸力學情況。
使用三維有限元素模型，包含掌骨、腕骨、尺骨、橈骨以及周圍相關的軟組織。模擬分成主要兩部分：第一部分是先模擬主動的最大腕背側彎曲，而第二部分在最大腕背側彎曲完成後，加入外力去模擬撞擊地面所受到的反力。
結果顯示，在最大腕背側彎曲運動過程中，舟狀骨在乘受到一個明顯的彎矩並在腰部因斷面積較小而有較大彎矩應力值，而撞擊的外力則有效的增強這彎矩的效應。當地面反力從垂直橈骨方向改為沿著橈骨方向，舟狀骨除了彎矩還會受到相當大的壓應力。因此，推測舟狀骨骨折應該是由這兩種彎矩及外部力量所造成的。

The scaphoid is the most frequently fractured carpal bone and the complications associated with scaphoid fracture are severe. Several studies showed that the primary cause of scaphoid fracture is “fall on an outstretched hand”; however the mechanical mechanism remained unclear. Therefore this study investigated the contact mechanics of scaphoid and adjacent bones under wrist maximum dorsi flexion which is a similar posture of falling on an outstretch hand.
A three-dimensional finite element model was created in this study, including metacarpal bones, carpal bones, radius, ulna, and related soft tissues. The loading was divided into two stages: First, to mimic an active wrist maximum dorsi flexion. Second, after the active wrist maximum dorsi flexion was achieved external force load would apply on the wrist to simulate the external reaction force from the ground.
The result showed the scaphoid was under a bending moment during the active wrist maximum dorsi flexion and the external force enhanced this bending mode. And this bending moment induced high bending stress at scaphoid waist because of the cross section is smaller. When the direction of the external force changed from radial perpendicular to along the radius axis, a highly compressive stress appeared within the scaphoid. Therefore, scaphoid fracture might occur due to the bending as well as the large force.

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