Thumb reconstruction with a wraparound free flap according to the level of amputation

We surgically treated 37 thumbs amputated distal or proximal to the metacarpophalangeal (MCP) joint using a wraparound free flap from the great toe for the reconstruction. We studied the functional results of the procedure according to the level of amputation and the fixation angle of the iliac bone block. The cases were divided into 2 groups: group 1, which comprised 25 cases with the level of amputation distal to the MCP joint, and group 2, which comprised 12 cases with the level of amputation at or proximal to the MCP joint. Opposition of the reconstructed thumb to the other fingers was completely possible in all cases in group 1. In group 2 opposition was completely possible in 6 cases in which the iliac bone block was fixated into the position of 30 degrees flexion and 45 degrees internal rotation; in the remaining 6 cases, in which the graft was fixated into the position of 30 degrees flexion and 30 degrees internal rotation, complete opposition of the reconstructed thumb to the ring and little fingers was not possible. We found that amputation of the thumb proximal to the MCP joint is not an absolute contraindication for the wraparound free flap reconstruction. We recommend fixating the iliac bone block into 30 degrees flexion and 45 degrees internal rotation to obtain better functional outcome in cases with amputation at or proximal to the MCP joint.