Changes in radiocarpal loading characteristics after proximal row carpectomy.
OBJECTIVE
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 degrees of extension and 20 degrees 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.
Hogan
Christopher J
CJ
Department of Orthopedic Surgery, Naval Medical Center Portsmouth, Portsmouth, VA 23708, USA.
McKay
Patricia L
PL
Degnan
Gregory G
GG
D001696:Biomechanical Phenomena; D002348:Carpal Bones / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D012667:Lunate Bone / Q000503:physiopathology / Q000601:surgery; D011183:Postoperative Complications / Q000503:physiopathology; D016059:Range of Motion, Articular / Q000502:physiology; D021361:Scaphoid Bone / Q000503:physiopathology / Q000601:surgery; D016474:Weight-Bearing / Q000502:physiology*; D014955:Wrist Joint / Q000503:physiopathology*