QUESTION: A patient's wrist fusion included insertion of a plate over the carpal bones, and resulted in asymptomatic extension deficits of index, middle, and ring fingers. Would you combine the impairment due to finger motion loss with that for the fusion?
ANSWER: It depends on which edition of the AMA Guides is used.
AMA GUIDES, FIFTH EDITION
Impairment for the wrist fusion would be determined using the final wrist (ankylosis) position. Figure 16-1b (5th, 437) provides the guides of wrist motion as 2 planes, (R/U). Using Figure 16-28 (5th, 467), a wrist in 10 degrees of extension (the ideal position for function) would have 21% upper extremity impairment (UEI), the impairment due to ankylosis (IA%). Using Figure 16-31 (5th, 469), a wrist fused in 5 degrees of ulnar deviation (the ideal position of function) would have 9% UEI. The two IA%'s...