Polydactyly

Dr. Greene's Answer

Often I’ve heard expectant parents say, “I’ll be happy as long as she has five fingers on each hand and five toes on each foot.” Extra fingers and toes, however, are relatively common and usually present no long-term problem. Polydactylism, or having one or more extra fingers or toes, is probably the most common abnormality of development found at birth.

Polydactylism is reported in about 1-2 per 1000 children. However, many of the simpler cases are taken care of in the nursery by the obstetrician or pediatrician and don’t show up in these statistics.

An extra finger or toe may be nothing more than a nubbin of soft tissue with no bone formation, it may be a full digit that forks off one of the five normal long bones of the hand or foot, or it may be a complete extra digit with its own extra long bone in the hand or foot — or almost any variation between these possibilities.

The most common form of polydactyly is a small, soft, extra finger that contains no bone. Many of these can be easily treated at birth by a physician who ties a suture tightly around the base. The extra digit falls off, and the normal-appearing hand or foot heals quickly.

If there might be bone in the extra digits, X rays should be obtained to give a clear picture of what is going on. In some instances, it is still difficult to decide which digit should be removed, and close observation of the function of the hands and feet as they develop can give the answer.

Complex polydactyly is usually not repaired until a child is one year old. Generally, the digit that is best aligned with the long bones is saved. When the other digit is removed, sometimes transferring tendons from the amputated digit will make the one that remains more normal. Sometimes a joint needs to be reconstructed, or a bony prominence shaved. If the case is complex, an orthopedic or plastic surgeon with expertise in hands and feet is preferred. Usually the results are excellent.

I’m glad to hear that your daughter is otherwise healthy and normal. Children with polydactyly should have a thorough physical examination to look for other abnormalities. There are over 30 rare congenital syndromes in which polydactyly is present. Most children with extra fingers or toes, however, are the wonderful normal, miracles that expectant parents can’t wait to meet.