Complete versus incomplete nonviable amputations of the thumb. Comparison of the survival rate and functional results.

81 patients with 84 complete (55) or incomplete (29) nonviable amputations of the thumb were studied to compare the survival rate and functional results between the two groups. 3 of these patients had bilateral thumb amputations. Of the 55 completely amputated thumbs, 43 survived (78 percent), while of the 29 incomplete nonviable amputations, 25 were salvaged (86 percent). Excluding patients with an amputation at the level of or distal to the interphalangeal (IP) joint, motion at the IP joint which did not exceed 40 degrees flexion even when a secondary procedure was done, did not show a statistical difference between the 2 groups. Average two-point discrimination was 14 mm for patients with complete amputations and 11 mm for patients with incomplete nonviable amputations. We conclude that incomplete nonviable amputations of the thumb are associated with a higher survival rate and better sensibility than complete thumb amputations, while motion at the IP joint does not differ between the two groups of patients.