The Modified 3-square Flap Method for Reconstruction of Toe Syndactyly

Bandoh reported the 3-square-flap method as a procedure for interdigital space reconstruction in patients with minor syndactyly. We recently modified this flap design so that it could be used in the treatment of toe syndactyly involving fusion of the areas distal to the proximal interphalangeal joint. With our method, the reconstructed interdigital space consists of 4 oblong flaps (A through D). Flaps A and D are designed on the dorsal side, flap B is designed on the frontal plane of the interdigital space, and flap C is designed on the plantar side. Flaps A, B, and C are raised immediately below the dermis in a manner that allowed slight fat tissue to adhere to each flap. Flap D is freed to a degree minimally needed for dislocation, while leaving a thick subcutaneous pedicle. Flaps A, B, and C are each folded in 90 degrees; flap D is dislocated to the proximal plane of the reconstructed digit, followed by skin suturing. In this process, suturing is avoided between flaps A and C, between flaps A and D, and between flaps B and D. During the period of 2011 to 2015, we treated 8 patients of toe syndactyly involving fusion distal to the proximal interphalangeal joint. Cases of congenital syndactyly received surgery between the ages of 8 and 11 months. Using this technique, flap ischemia/necrosis was not observed. During the postoperative follow-up period, the interdigital space retained sufficient depth without developing any scar contracture. No case required additional surgery.