Syndactyly

Syndactyly is a term used to describe webbed or conjoined digits (fingers or toes). It may occur as an isolated finding or may be a symptom of a genetic syndrome. There are over 300 genetic syndromes that involve syndactyly, such as Apert syndrome and Saethre-Chotzen syndrome. There are many different ways to classify or group non-syndromic (isolated) syndactyly. Presently, researchers classify the different types of syndactyly based on how severe the syndactyly is, which digits are involved, how the trait appears to run through families, and whether an underlying gene mutation has been identified. Using this system, nine different non-syndromic types of syndactyly have been defined.

Syndactyly is caused by a mixture of genetic and environmental factors. In about 10-40% of individuals with syndactyly, there is a family history. Syndactyly can run through families in many different ways, depending on the underlying cause. When isolated, it can be inherited in an autosomal dominant, autosomal recessive, or X-linked recessive manner. Treatment usually involves surgery to separate the digits.