Syndactyly Classification

• Syndactyly is the most common congenital hand anomaly
• Acrosyndactyly: fusion of distal parts of the digit with proximal fenestration
• Isolated syndactyly has an autosomal dominant inheritance with variable penetrance
• Frequency of syndactyly: thumb-index (5%), index-middle (15%), middle-ring (50%), ring-little (30%)

Type                  Characteristics
Simple              Soft tissue alone
Complex          Soft tissue and bone
Incomplete      Partial connection between digits
Complete         Complete connection between digits
Complicated   Extensive soft-tissue abnormalities or a hodgepodge of abnormal bones