Polydactyly and Syndactyly of the Hand

Polydactyly is a duplication of the fingers, and syndactyly is fusion of the fingers. These are the most common hand anomalies seen in the newborn. Both polydactyly and syndactyly can occur in isolation or as part of a syndrome. Polydactyly is classified based on the radial to ulnar location of the duplicated digit. Syndactyly is described as simple or complex based on the involvement of abnormal soft tissue or bony connections between the fused digits. Advances in genetics and molecular biology have increased our understanding of the pathophysiology of both conditions. Both polydactyly and syndactyly of the hand are typically identified at birth or shortly thereafter. When these anomalies are present, the presence of other congenital abnormalities and syndromes should be considered. Most congenital polydactyly and syndactyly problems can be managed surgically to improve hand function and appearance.