ObjectiveTo investigate the effectiveness of dorsal pentagonal flap for reconstruction of the web space in congenital toe syndactyly. MethodsBetween January 2009 and June 2014, 10 patients with congenital toe syndactyly were treated for web space reconstruction with dorsal pentagonal flap. There were 6 boys and 4 girls with the average age of 42 months (range, 8 months to 9 years). The congenital toe syndactyly located at the left foot in 5 cases, the right foot in 4 cases, and both feet in 1 case; 7 patients had polydactyly and 1 patient had brachydactylia. During followup, the toe function and web space appearance, web space depth, and web space gradient were observed to evaluate the effectiveness. ResultsAll 13 flaps survived and incisions healed by first intention. Ten patients were followed up 6-50 months (mean, 26 months). The skin color and texture in 13 reconstructed web spaces were close to normal web space. In 9 patients undergoing web spaces reconstruction of single foot, the abduction angle of toes was (42.879±3.703)° at the injured side, showing no significant difference when compared with the normal side [(45.922±2.657)°] (t=-2.004, P=0.062); the web space depth was (1.881±0.266) cm at the injured side and was (1.631±0.202) cm at the normal side, showing significant difference (t=2.248, P=0.039); and the web space gradient was (42.733±3.421)° at the injured side and was (41.189±5.593)° at the normal side, showing no significant difference (t=0.707, P=0.490). The web space appearance, web space depth, and web space gradient were close to those of the normal web space in 1 patient undergoing bilateral web spaces reconstruction. ConclusionWeb space reconstruction with dorsal pentagonal flap is easy to perform with reliable blood supply and low re-operated rate. The cosmetic and functional results are satisfactory.