is the common name for syndactyly
affecting the feet. It is characterised by the fusion of two or more digits of the feet. This is normal in many birds
, such as ducks
, such as frogs
; and mammals
, such as kangaroos
. In humans it is considered unusual, occurring in approximately one in 2,000 to 2,500 live births.
There are various levels of webbing, from partial to complete. Most commonly the second and third toes are webbed or joined by skin and flexible tissue. This can reach either part way up or nearly all the way up the toe.
This condition is normally discovered at birth. If other symptoms are present, a specific syndrome may be indicated. Diagnosis of a specific syndrome is based on family history, medical history, and a physical exam. Webbed toes are also known as "twin toes," "duck toes," and "tiger toes."
The exact cause of the condition is unknown. In some cases, close family members may share this condition. In other cases, no other related persons have this condition. The scientific name for the condition is syndactyly
, although this term covers both webbed fingers and webbed toes. Syndactyly occurs when apoptosis
or programmed cell death during gestation is absent or incomplete. Webbed toes occur most commonly in the following circumstances:
It is also associated with a number of rare conditions, notably: