An On-Top-Plasty Reconstruction for Complicated Radial Polydactyly.

The clinical presentation of radial polydactyly can vary greatly. Careful planning and appreciation of the anatomic subtleties provides alternative surgical options to improve patient outcomes. We present a case of a well-formed accessory web space thumb and a hypoplastic primary thumb. Rather than excising the accessory digit, we performed a spare-part, on-top-plasty reconstruction to replace the diminutive distal phalanx of the primary thumb. This novel case applied the principle of spare-part surgery to reconstruct a more aesthetic and functional reconstructed digit.