Foot Syndactyly: A Clinical and Demographic Analysis

SLR - July 2017 - Jana Balas

Reference: Kim JH, Kim BJ, Kwon ST. Foot Syndactyly: A Clinical and Demographic Analysis. Archives of Plastic and Reconstructive Surgery. 2016 November; 43(6).

Scientific Literature Review

Reviewed By: Jana Balas, DPM
Residency Program: MetroWest Medical Center, Framingham, MA  

Podiatric Relevance: Syndactyly of the foot is the second most common congenital foot anomaly. Isolated foot syndactyly occur four times more frequently than isolated hand syndactyly. However, despite its higher incidence, foot syndactyly has been less frequently discussed in the literature, as compared with hand syndactyly. This study presents a demographic analysis, clinical features, surgical technique and postoperative outcomes of foot syndactyly. The technique used by the surgeon in this study may be useful for foot and ankle specialists who treat this condition.

Methods: This was a retrospective chart review of 118 patients (155 feet) treated by a single surgeon in the Department of Plastic and Reconstructive Surgery. During a 25-year period between January 1990 and December 2014, these patients all underwent surgical correction for foot syndactyly. Clinical features evaluated were partial or complete, simple or complex and unilat­eral or bilateral involvement. Functional outcome and postoperative complications, such as web creep, flexion contrac­tures and angulation deformity, were assessed. The inter­digital triangular flap was designed to reconstruct the web space with methods originally described by Cronin in 1956. The dorsal triangular skin flaps were marked from the point of the metatarsal head dimple to the interdigital crease. The triangle was designed such that the ratio of the height to the base was greater than 1.5 so that it could reach the plantar inter­digital crease. A zig-zag incision was designed to place the tip of the triangle at the joint level. The remaining skin defect was then covered using a full-thick­ness skin graft (FTSG) harvested from the inguinal area. In cases of multiple web space involvement that required two or more operations, the next operation for the neigh­boring web space was delayed, with a mean interval of 9.5 months.

Results: Details of the demographic and clinical findings are discussed. Of the 118 patients with syndactyly (155 feet, 194 webs) who received surgery, only three patients developed postoperative com­plications. These included misaligned web creep requiring surgical revision, hypertrophic scar and a pressure sore of the heel that was resolved with conservative management. In addition, six of the 118 patients were referred from other hos­pitals due to secondary complications from syndactyly correc­tion. All of these secondary cases were successfully corrected by the afore­mentioned surgical methods.

Conclusions: The incidence of hand or foot syndactyly is known to be one in every 2,000 to 2,500, which makes syndactyly the second most common congenital limb malformation after poly­dactyly. Hand syndactyly frequently occurs in the third interdig­ital web space, while foot syndactyly most commonly occurs in the second interdigital web space. Isolated foot syndactyly is known to be more frequent than isolated hand syndactyly. Despite this higher incidence, there is less discussion of foot syndactyly in the literature. Foot syndactyly surgery using a dorsal skin flap and a sufficient FTSG may be necessary for better post­operative outcomes and lower complication rates.