Effects of axial load on in vivo scaphoid and lunate kinematics using four-dimensional computed tomography

This in vivo study investigated the effect of axial load on lunate and scaphoid kinematics during flexion-extension and radial-ulnar deviation of the uninjured wrist using four-dimensional computed tomography. We found that applying axial load to the wrist results in a more flexed, radially deviated and pronated position of the lunate and scaphoid during flexion-extension of the wrist compared with when no load is applied. A larger pronation and supination range of the lunate and scaphoid was seen when the wrist was flexed and extended under axial load, whereas a larger flexion and extension range of the lunate and scaphoid occurred during radial-ulnar deviation of the wrist when axial load was applied.