A volar approach to on-top plasty for correction of radial polydactyly: a case series of 21 patients.

Correction of unequal radial polydactyly in which neither thumb duplicates possess both well-developed proximal and distal components, remains challenging. Current techniques using on-top plasty techniques require circumferential incisions, often resulting in postoperative swelling and dorsal scars. We described our experience using a volar approach to achieve better aesthetic and functional results. Twenty-one patients underwent this surgery between 2008 and 2018, with a mean follow-up of 5.1 years. The mean flexion-extension arc for the metacarpophalangeal joint was 75° and that of the interphalangeal joint was 43°. Mean percentage of key, tripod and tip pinch strength were 77%, 79% and 77%, respectively, when compared with the contralateral side. The Vancouver Scar Scale showed an average score of 1.2. We conclude from our study that the volar approach to on-top plasty is a good technique for the correction of unequal radial polydactyly, with good functional and aesthetic results.Level of evidence: IV.