Use of single-staged transmetatarsal trimmed great toe transfer for reconstruction of a thumb amputation at the carpometacarpal joint.

Background: Reconstruction for proximal thumb amputation at the carpometacarpal (CMC) joint level is extremely challenging. All thenar muscles are lost and other fingers might be lost or injured. Transmetatarsal trimmed great toe (TGT) transfer may be an option in such cases.

Methods: Between 2012 and 2018, 11 patients who had amputation of the thumb at the CMC joint level were reconstructed by transmetatarsal TGT transfer in a single stage. There were seven cases in which the right hand was affected and four cases in which the left hand was affected. Three cases involved a contracture scar at the thumb stump and required web space reconstruction. Average follow-up was 33.9 months (range: 12-76 months) RESULTS: All toe transfers survived. The average of static two-point discrimination (S2PD) was 14.6 mm; the average scores of the Quick Disabilities of the Arm, Shoulder, and Hand (quickDASH) questionnaire and the Michigan Hand Outcomes Questionnaire (MHQ) were 18.6 and 73.8, respectively. Two cases did not achieve opposition due to mispositioning of the neothumb. In nine cases achieving opposition, the Kapandji score ranged from 4 to 9, pinch ranged from 3 to 11 lbs, and grip ranged from 15 to 86 lbs. In the donor foot, three patients had neuroma and two had a new callus on the palmar side of the second and third metatarsal heads. The average foot and ankle disability index score was 91.6.

Conclusion: Single-staged transmetatarsal TGT transfer is safe and useful for thumb reconstruction at the CMC joint level. This reconstructive method is suitable for manual workers, especially in the developing countries.