Christopher J. Hogan, MD a * [MEDLINE LOOKUP] Patricia L. McKay, MD b [MEDLINE LOOKUP] Gregory G. Degnan, MD c [MEDLINE LOOKUP]
Purpose To document the changes in wrist loading that occur after proximal row carpectomy in a cadaver model.
Methods The normal radioulnar carpal pressure distributions of 7 cadaver wrists were measured using super-low-pressure-sensitive film. Proximal row carpectomies were performed and the loading characteristics re-evaluated.
Results In the lunate fossa the contact area increased 37%, the average contact pressure increased 57%, and the location of the contact moved radially 5.5 mm. With wrist motion between 40° of extension and 20° of flexion the volar/dorsal excursion of the lunate fossa contact point increased by 108%.
Conclusions Significant changes in radiocarpal loading occur after proximal row carpectomy. The increased radiocarpal excursion with wrist motion may explain the low incidence of radiocapitate arthritis in patients who have had proximal row carpectomy.
The Journal of Hand Surgery. November 2004 Volume 29 Number 6.