Survival factors in replantation and revascularization of the amputated thumb--10 years experience.

An unabridged series of 73 thumb amputations subjected to replantation or revascularization surgery in the years 1971 to 1980 has been examined in detail as a combined prospective and retrospective study to determine the factors playing a role in survival and failure. The causes of failure and complications are demonstrated. The overall failure rate was 27%. The factors influencing the outcome were: the injury--mechanical type and degree of amputation; the patient--age and amputation level; and the surgeon--frequency of utilization of vein grafts. The highest failure was seen in the complete amputation with avulsion/diffuse crush injury group (63%). Incomplete amputations had the lowest failure rate, particularly if the injury type was guillotine/local crush and at a level proximal to the metacarpophalangeal joint. Patients aged 11 to 20 years had a low failure rate (18%) whereas children under 5 years had a high failure rate (40%). Arterial thrombosis was the most frequent complication and cause of failure. The surgeon could modify the result by frequent use of vein grafts for arterial reconstruction and by reoperation for thrombotic complication. Five thumbs failed to revascularize at the primary operation and were removed at this primary operation.