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Updated: Sep 16, 2026

Method to Measure Tone of Axial and Proximal Muscle
Published on: December 14, 2011
Axial loading induces rotation of the proximal carpal row bones around unique screw-displacement axes
M Kobayashi1, M Garcia-Elias, L Nagy
1Department of Orthopedics, Mayo Clinic, Rochester, MN 55905, USA.
Abstract:
The changes in carpal bone alignment secondary to the application of an axial compressive load through the major wrist motor tendons while the wrist is kept in neutral position (isometric loading) have been investigated on 13 fresh cadaver specimens using a biplanar radiographic method of kinematic analysis. The scaphoid, lunate and triquetrum rotate an average of 5.1, 4.2, and 3.8 degrees, respectively, around different screw displacement axes, all implying flexion, radial deviation and supination. Based on these findings, a new interpretation of the mechanism by which the wrist remains stable under physiologic loads is provided.
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