Abstract
An experimental model that uses a static positioning frame, pressure-sensitive film, and a microcomputer-based videodigitizing system was used to measure the contact areas and pressures in a group of wrists in their “normal” state, after ligament sectioning, which resulted in stage III perilunate instability and then following different types of simulated carpal fusions. Compared with a normal wrist, there is an overall decrease in load in the lunate fossa and a significant increase in load in the scaphoid fossa in the wrist with stage III perilunate instability. Scaphoid-trapezium-trapezoid and scaphoid-capitate fusions transmitted almost all load through the scaphoid fossa. Scaphoid-lunate, scaphoid-lunate-capitate, and capitate-lunate fusions all distributed load more proportionately through both scaphoid and lunate fossae. The positioning of the carpal bones within a limited carpal fusion was also found to affect the load distribution in the wrist. The scaphoid-lunate, scaphoid-lunate-capitate, or capitate-lunate fusions, with attention to the relative carpal alignment within the limited fusion seem to offer more promise for treatment of perilunate instability biomechanically than the scaphoid-trapezium-trapezoid or scaphoid-capitate fusions.
Original language | English |
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Pages (from-to) | 120-128 |
Number of pages | 9 |
Journal | Journal of Hand Surgery |
Volume | 15 |
Issue number | 1 |
DOIs | |
State | Published - 1990 |