Syndactyly of upper limb. Morphogenesis, classification, and management

The distinction between primary and secondary syndactyly is made on the basis of their relation to the morphogenesis. The latter is associated with antecedent malformation which results in subsequent refusion of parts. Based on these considerations, a practical classification is suggested. The management of the various types of malformations is considered in relation to the complexity of the structures involved. Certain deformities require very early treatment in order to permit prehensile function to the developing infant, or to release the impaired part. It is desirable to complete all surgery before the child enters school. The severe complex syndactyly could rarely be solved by one operation. Normal appearance and function are rarely attained and, with growth, newer problems of imbalance and contracture appear. While rehabilitation of the hand is seldom needed for the children with cutaneous syndactyly, the severe deformities associated with complex syndactyly often require supervision in order to regain the potential function and simple dynamic splints are very helpful.