Birth defects of the fingers and toes can occur while the baby is developing in the womb. For example, the baby may have very few fingers or toes. Or she may be born with extra fingers or toes.

In amniotic band syndrome, defects of the hands, fingers, and toes (and other abnormalities) occur when parts of the body become constricted by thin strands of tissue from the amniotic sac. The amniotic sac contains the amniotic fluid that surrounds the developing fetus in the womb. The strands wrap around the fetus, like strings or rubber bands, trapping parts of its body and restricting its growth.


Polydactyly is the presence of extra fingers or toes. The little fingers or the thumbs of the hands and feet are the most frequently duplicated. The extra finger or toe may be just a bulge of fleshy tissue, or it may be fully functional and have its own nerve endings, bones, and joints.




Syndactyly consists of the appearance of an interdigital web between the fingers or toes (the fingers are fused). In syndactyly, the fingers or toes do not spread, resulting in a webbed hand or foot. In simple syndactyly, the soft tissues fuse together. In complex syndactyly, the bones and soft tissues fuse together.

Both polydactyly and syndactyly can occur alone or as part of a genetic syndrome, such as Apert syndrome.

Before birth, doctors can sometimes diagnose these defects during an ultrasound .

After birth, doctors often take x-rays and may do other imaging tests to determine which bones are affected. When the defects appear to run in the child’s family or if doctors suspect that the child has a genetic syndrome, they also examine the child for other physical abnormalities and take a blood sample for genetic testing.

Treatment of finger and toe defects

  • Surgery

  • Prosthesis

Surgery may be done to separate the syndactyly of the fingers or toes and improve function. Surgery may be done to remove an extra finger or toe.

Some children who are missing a finger or toe need a prosthesis, an artificial device that replaces the missing body part.