gms | German Medical Science

Objectives/Interrogation: To investigate the validity, efficacy and safety of utilizing a reversed vascularized second metatarsal composite flap for Manske type IIIb and IV hypoplastic thumb reconstruction, without impairing the functions of the donor site.

Methods: An osteocutaneous flap containing a section of second metatarsus and its distal head was transferred in reversed position to reconstruct metacarpophalangeal joint with trapezium remnant or the base of second metacarpus, dorsalis pedis artery anastomosed to residual radial artery or the common digital artery; great saphenous vein to cephalic or opisthenar vein. Donor site was reconstructed by a split half of the third metatarsus. Various staged reconstructions were commenced months later. The thumbs were evaluated with grip, key-pinch and the skills in performing daily activities through a detailed VAS questionnaire.

Results and Conclusions: From May 2014 to Jan 2017, 15 patients, with 7 type IIIB, and 8 type IV thumbs were reconstructed. 13 metatarsal flaps had complete survival (86.7%). With average of 19.3-months follow-up, the reconstructed thumbs had pleasant appearance; The donor foot presented in good appearance without any sign of impaired function. X ray further evidenced good bone fusion in second and third metatarsal. Patients and parents have high recognitions and acceptance on the new thumb.

Reconstruction of an unstable hypoplastic (Manske type-IIIB and IV) thumb with use of a vascularized metatarsus is an effective alternative to pollicization of the index finger, especially when parents insist on saving the thumb at all costs.