CONTRIBUTION OF THENAR FLAPS FOR DISTAL TISSUE LOSS OF THE LONG FINGERS: 86 CASES

Abstract

Purpose of the study: Distal amputation of the long fingers with loss of dorsal or volar tissue may leave bone exposed requiring fingertip reconstruction to restore sensorial and tactile function. Several methods have been proposed for fingertip reconstruction. Among the methods the most widely used, thenar flaps predominate because of they are reliable and easy to perform but especially because of the very high-quality tissue function achieved.

Material and methods: We report a series of 86 patients who presented an amputation of a long finger during a 4-year period (January 1998 to December 2002). A tenar flap was constructed within 24 of the operation. Mean patient age was 26 years; 80% of the accidents were occupational accidents; tissue loss was caused by sharp instruments in 72% of the cases; three-quarters of the cases involved the left non-dominant hand; the greatest damage was to the middle finger in 58% of cases. Loss of dorsal tissue was noted for 80% of the amputations. Trunk anesthesia was used for all patients to achieve cover with a thenar flap with a proximal pedicle in 80%. The flap was weaned from its blood supply at 18 days on average.

Results: Outcome was assessed with three criteria at mean follow-up of one year. Subjectively, 80% of patients were satisfied with the operation. Permanent flexion of the distal interphalangeal joint was totally absent in 70% of patients. Using the British Medical Research Council, sensibility was scored S3 in 60% and S2 in 40%.

Discussion: Described as early as 1926, the thenar flap is a novel method for achieving a cutaneous cover very close to the anatomic fingertip. Several drawbacks have nevertheless been formulated, namely permanent flexion of the distal interphalangeal joint, cutaneous sequelae at the donor site, and the «blind» nature of the flap which can be devoid of sensitivity. Analyzing the results obtained in our series showed that harvesting a flap in the middle of the thenar zone avoiding the medial region which raises the risk of a cheloid scar, the risk of distal interphalangeal flexion can be avoided by starting active-passive rehabilitation exercises as early as possible. At two months, the fingertip starts gaining sensitivity via the periphery.

Conclusion: Thenar flaps are reliable, easy to perform flaps which provide an attractive solution to the reconstruction of long fingers.