Feasibility of partial A2 and A4 pulley excision: Effect on finger flexor tendon biomechanics

We investigated the effect of partial excision of the A2 and A4 digital pul leys, separately and in combination, on finger angular rotation and the ene rgy for finger flexion. Statistically significant decreases in angular rota tion resulted only after 50% and 75% excision of A2, A4, or A2 and A4 in co mbination. Work of flexion trends were weak and none of the changes were st atistically significant. Although optimal finger function relies on the int egrity of the A2 and A4 pulleys to maintain the efficiency of the digital f lexor system, these data suggest that the A2 and A4 pulleys can be excised up to 25%, either separately or in combination, without significant effects on angular rotation. Decreases in total angular range of motion after 50% and 75% pulley excision were small, even for combined pulley excision (9 de grees +/- 3 degrees and 15 degrees +/- 5 degrees [mean +/- SD], respectivel y), and may be clinically acceptable. Copyright (C) 1999 by the American So ciety for Surgery of the Hand.