Refinement of Surgery for Postaxial Polysyndactyly of the Toes

Abstract

Purpose Treatment for polysyndactyly of the toes aims at cosmetic improvement but the lateroplantar rotation of the new fifth toe remains challenging. This study evaluated our novel surgical procedure for postaxial polysyndactyly of the toes. Materials and Methods Patients with postaxial polysyndactyly involving the fourth, fifth, and sixth toes treated in 2007 to 2017 with a minimum follow-up duration of 1 year were retrospectively investigated. Our aims of surgery for this condition were to avoid excessive lateroplantar rotation of the new fifth toe by using a proximally elongated plantar “shark-fin flap” and to make the tip of this toe appear to be naturally pointing inward by using the dog-ear component of the flap on the tip of the toe. The excess skin of the shark-fin flap was grafted onto the lateral surface of the fourth toe. Lateroplantar rotation of the fifth toe in these patients was compared with that in photographs of the feet of 96 normal 4-year-old children. Results A total of 11 feet in 10 patients (6 male, 4 female; mean age 1.3 years) were analyzed. Syndactyly between the fourth and fifth toes was complete in 3 feet, incomplete at the level of the distal interphalangeal joint of the fifth toe in 5, and incomplete at the level of the proximal interphalangeal joint of the fifth toe in 3. Lateroplantar rotation of the fifth toe, evaluated by the mean angle between 2 intersecting lines extending from the proximal nail fold of the third and fifth toes, was 25 ± 10° in normal feet and 0 ± 12° in operated feet with polysyndactyly. The absolute left-right difference in this angle was 7 ± 5° in normal children and 22 ± 12° in patients with polysyndactyly. Valgus deformity of the new fifth toe improved in all patients during a mean postoperative follow-up of 3.8 years. Conclusions Using our procedure, no excessive lateroplantar rotation has been observed when the tip of the fifth toe is inclined inward using a dog-ear flap component. This procedure could be useful in patients in whom the cosmetic outcome is a priority.