Publication

Physical equilibrium of the normal wrist and its relation to clinically defined "instability"

Journal Paper/Review - Apr 1, 1995

Units
Keywords
PubMed
Doi
Link
Contact

Citation
Zdravkovic V, Jacob H, Sennwald G. Physical equilibrium of the normal wrist and its relation to clinically defined "instability". J Hand Surg Br 1995; 20:159-64.
Project
Type
Journal Paper/Review (English)
Journal
J Hand Surg Br 1995; 20
Publication Date
Apr 1, 1995
Issn Print
0266-7681
Issn Electronic
Pages
159-64
Publisher
Brief description/objective

The rotational stability of the proximal carpal row was tested on six unembalmed human cadaver hand specimens. The physiological load conditions were stimulated by loading the wrist flexor and extensor tendons. Pure torque was introduced to the lunate, scaphoid and triquetrum, one at a time, by means of a dynamometer wrench, forcing the bones loaded to perform a flexion-extension motion. A truly stable state of equilibrium could be found in the normal wrist only under axial load. A uni-directional coupling was observed through the scapho-lunate ligament as a counteraction to a tendency for the lunate to extend and the scaphoid to flex. The triquetrum and lunate moved together, showing close coupling in both directions. As conclusion: a stable wrist can be defined as one which, while being loaded within a physiological range of stress, does not deviate from a stable state of equilibrium (the ability to return to a single position when disturbed) at any point within the whole physiological range of motion.