Syndactyly refers to a congenital fusion of two or more digits and is caused by failure of differentiation of the tissues between the fingers at 5th-8th week of intrauterine life.
This could be classified as simple (only the skin and soft tissue) or complex (bony involvement, frequently there is also neurovascular involvement).
Traditionally, surgery was postponed until age 3-4 years but currently many surgeons do release at age 9 months to 1 year. Argument for delaying surgery is to avoid postoperative scarring, which may be more common in infants.
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