When Your Child Has a Congenital Digital Deformity
Your newborn has been diagnosed with a congenital digital deformity. Congenital means present at birth. A digit is a finger or toe. Deformity means a problem with the shape or structure of a body part. This diagnosis may have left you scared or worried. But these problems are often very treatable. And your child will likely have fully functional hands and feet. For a thorough evaluation of your child’s hands or feet, you may be referred to an orthopedist, a doctor specializing in treating bone and joint problems. Your child may also see a hand or foot surgeon, or a plastic surgeon. Because many of these conditions run in families, you may also be referred to a genetic specialist. This is a person who studies inherited conditions.
A child with polydactyly has extra fingers or toes. Usually, a child has the extra digit next to the thumb, big toe, little finger, or little toe.
Causes: As a baby develops in the mother's uterus, the hand or foot starts out in the shape of a paddle. The paddle splits into separate fingers or toes. In some cases, too many fingers or toes form.
Diagnosis: The extra digit may be connected by skin, muscle, or bone. Your baby's healthcare provider may take an X-ray to see how much bone is involved. This determines how or if surgery is needed.
Treatment: Polydactyly is often treated with surgery to remove the extra digit or digits. If there is no bone involved, the extra digit may be tied off. If surgery is needed, the surgeon usually waits until the child is age 6 months or older. This makes the surgery safer for the child.
Long-term outcome: If polydactyly in the foot isn’t treated, the child may have a problem fitting into shoes. With or without treatment, the hand or foot usually works normally. With treatment, the hand or foot can look closer to normal. In some cases, the digit that was next to the extra one is smaller than usual.
A child with syndactyly has fingers or toes that are joined at the edges. This condition is sometimes called webbed fingers or toes. The child may have only a small space between two fingers or toes. Two fingers or toes may share skin but have separate bones and nails. Or the fingers or toes may be fused, so that they share bone and have one nail. In rare cases, a digit is missing completely.
Causes: As a baby develops in the mother's uterus, the hand or foot starts out in the shape of a paddle. The paddle later splits into separate fingers or toes. In some cases, fingers or toes fail to separate.
Diagnosis: The digits may be connected by skin, muscle, or bone. Your child's healthcare provider may take an X-ray to see how much bone is involved. This determines how surgery is done.
A hand with syndactyly that is functioning well doesn’t always need treatment. If surgery is done, the goal is to help the hand work better. If skin is needed, it may be taken from other parts of the body. If bone is needed, it may be taken from the foot or other areas. An occupational therapist or physical therapist specializing in hands can help prepare the child before and after surgery. After surgery, the child may be given a special device to wear while the hand heals.
A foot with syndactyly rarely requires treatment. The foot will often work normally without treatment. And surgery often can’t make the foot look completely normal.
Long-term outcome: Even if it’s not treated, syndactyly often doesn’t affect hand or foot function. If surgery is done to improve hand function, it is often very successful. But it’s difficult to make the hand look completely normal. Fingers that were fused are often smaller than usual. Talk with the healthcare provider about the cosmetic outcome you might expect for your child.
Overlapping or Underlapping Toes
This condition is often called “curly toes.” It often affects both feet. The little toes are commonly affected.
Causes: The cause may be a tight tendon in the foot pulling one toe under or over another one. The cause is not always known.
Diagnosis: This problem may be seen in a newborn. Most often, though, it is not noticed until the child starts to walk.
Treatment: Treatment focuses on moving the toes apart and aligning them correctly. This helps prevent problems with the foot later on. Treatment may include:
Toe spacers between the toes to hold them apart, or taping toes to hold them apart.
Splinting of the toes to straighten them or hold them apart.
Shoe inserts (orthotics) to help the toes align correctly.
Surgery to release a tight tendon and straighten the toes. Surgery is often not done until a child is older.
Long-term outcome: A child with this condition may have feet that work well even with no treatment. If a child has overlapping toes that are not treated, problems can develop later as the child starts walking. These problems include trouble fitting shoes, joint deformity, callus formation, or skin breakdown due to rubbing. With treatment, the child generally has good results.
Annular Bands (Amniotic Bands)
This painless condition appears as a deep crease on the skin of a newborn. Most commonly, bands make the digit look abnormal, but cause no other problems. In more serious cases, bands cut off blood flow (circulation) to the digit. This can cause the digit to be malformed. It can also cause tissue death resulting in loss of the digit.
Causes: Annular bands are thought to be caused by bands of amniotic tissue wrapping around a finger or toe while the baby is still in the womb.
Diagnosis: This problem is often noticed when the baby is examined at birth.
Treatment: If circulation to the digit is good and the digit works normally, treatment is not needed. If treatment is needed, surgery is done to release the band. The quality of blood flow to the digit helps determine the need for and the timing of surgery.
If blood flow to the digit is good, the surgeon will likely wait 3 to 6 months before doing surgery. This makes surgery safer for the child. During this waiting period, watch for signs of a circulation problem. These include skin color changes and the digit feeling cold to the touch.
If blood flow to the digit is poor, emergency or urgent surgery is needed to release the band and try to save the digit from tissue death. In some cases, surgery can't save the finger or toe. It then would need to be removed.
Long-term outcome: If released, the digit will most likely grow normally and catch up in size with the other digits. If a digit has full blood supply but is not released, it may work normally. But it will stay smaller than other digits.
June 21, 2018
Bass, Pat F. III, MD, MPH,Joseph, Thomas N., MD