Accessory Movement of the Lunate during Active Flexion and Extension Motion of the Wrist

Satoru Kai, Seiichi Yasumoto and Seiichiro Takahashi

This study investigated the accessory movement of the lunate in the volar-dorsal direction during active flexion-extension motion of the wrist. The right wrist of a healthy 50-year-old (right-handed) male was studied using an ultrasound diagnostic instrument to measure the wrist's continuous motion from (neutral to) flexion to extension (back to neutral). The distance between the dorsal plane of the radius and that of the lunate was measured in each image. The results showed that the lunate moved 0.5 mm dorsally during flexion, and it moved 1.5 mm in the palmar direction during extension. The authors hope that this study will serve as a frame of reference in the evaluation of a given mode of physical therapy prescribed for subjects with joint dysfunction.

Journal of Physical Therapy Science, Vol. 18 (2006) , No. 2 161-164

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