Polydactyly, ie, the presence of extra fingers or toes is a common
condition. Oftenly the extra digits are incompletely formed and lack proper muscular connections and, hence, are useless. This condition is usually bilateral. Polydactyly is inherited as a dominant trait.
Ectrodactyly means absence of a digit. This deformity is usually unilateral.
Brachydactyly means abnormal shortness of fingers or toes. This anomaly is usually inherited as a dominant trait and is generally associated with a short stature.
Syndactyly (fused digits) is the most frequent congenital anomaly of the limbs. It is more frequent in the foot than in the hand. This condition is inherited as a simple dominant or simple recessive trait. In most of the cases this anomaly is present as cutaneous syn-dactyly in which adjacent digits are fused simply by a skin web because this web failed to break down during development. Such digits can be easily separated surgically. However, in a more severe form of syndactyly, called osseous syndactyly, the bones of adjacent digits are fused together.