Cross-finger Flap to the Thumb: Quest for an Alternate Donor

Abstract

Background Distal thumb injuries are managed by multiple local and regional flaps. The cross-finger flap (CFF) is one versatile flap used to cover such defects. The donor finger to the thumb is classically described to be the index finger (IF). However, with the index finger being the second most important finger, it causes further debilitation of the already injured hand. Our aim was to find an alternate donor finger to spare the index finger. Methods and Materials A prospective observational study was conducted on 10 patients with distal thumb injuries who were admitted between November 2018 and July 2019. Ring finger (RF) was used as donor for CFF in all the cases. The subjects were assessed for first web space angle, Kapandji score, total range of movement (TRM) of long fingers, and global hand function using Michigan hand outcome questionnaire (MHQ) after flap division. Results There was no first web contracture and TRM of IF remained unaffected. However, TRM of RF was significantly reduced. But this being a relatively unimportant finger, there was no significant reduction in global hand function, as evaluated by the MHQ score. Conclusion The ring finger is a good alternative for index finger as donor for CFF to the thumb, because it provides adequate tissue along with comfortable positioning and easy maintenance of local hygiene. Moreover, it preserves global hand function by sparing the IF.

Keywords

• cross-finger flap
• donor finger
• ring finger
• thumb injury
• thumb reconstruction