Bone, Joint and Muscle Conditions
Amniotic Band Syndrome
What is amniotic band syndrome?
While babies are in the womb, a sac of fluid (amniotic sac) surrounds and protects them. In amniotic band syndrome, thin strands of tissue form inside this sac. The strands tangle around the baby, like strings or rubber bands, trapping parts of their body. Pressure from the strands can affect the way your baby forms.
As your baby grows, the strands make creases, or indentations, in their tissue. These creases are called amniotic bands. (They are also known as constriction bands or constriction rings.) Most bands affect only the outer layers of soft tissue, like the baby’s skin and the tissue just under their skin (subcutaneous tissue). Tighter bands may go as deep as the bone.
Bands happen most often around a baby’s arms or legs. Often, the bands go all the way around the limb. Some go only partway around (incomplete bands). Bands can also form around the head, face, chest or belly (abdomen). The exact effects depend on where the bands are and how early they began.
In the mildest cases, amniotic band syndrome causes a single, shallow crease on 1 limb. The crease can be seen, but it doesn’t cause problems with the way the limb works. Some children have multiple deeper bands.
In more serious cases, bands that compress blood vessels may reduce blood flow to parts of your baby’s body. This may limit growth or injure tissue as the baby develops. Bands can be so tight that the tissue past them cannot survive because it doesn’t get enough blood. These bands may cut off fingers, toes or other parts of the arms or legs before a baby is born (congenital amputation or intrauterine amputation). If bands injure but do not amputate your baby’s fingers or toes, the digits may heal together in the womb and cause a type of syndactyly (acrosyndactyly). Sometimes the digits are fused only at the tips.
Amniotic band syndrome is rare, and the cause is not known. This condition is known by many other names, including:
- Amniotic constriction bands
- Constriction band syndrome
- Congenital constriction rings
- Streeter anomaly
- Streeter bands
- Streeter dysplasia
If bands compress nerves, they may cause other problems. A band around a nerve that controls the lower leg and foot (peroneal nerve) is 1 cause of clubfoot.
If bands cross your baby’s head, face, chest or abdomen, they may cause more serious problems with your baby’s development. Bands around the head or face may cause encephalocele or cleft lip and palate. Bands around the abdomen may cause problems with internal organs, like kidney problems or gastroschisis. Bands that cross the chest may cause heart defects.
Amniotic Band Syndrome at Seattle Children’s
Each baby with amniotic band syndrome needs a treatment plan tailored to them.
At Seattle Children’s we bring together experts from:
We work as a team to evaluate your baby and make a treatment plan that meets their needs.
Our surgeons are experienced at performing surgeries to release bands and correct the effects of bands on the way your baby formed.
The doctors at Seattle Children’s also provide prenatal consultations if an ultrasound before birth shows that your baby may have amniotic band syndrome.
We have the largest group of board-certified pediatric radiologists in the Northwest. Our radiologists have special expertise using ultrasound to look for bone and joint changes so we can work with your child to help prevent future problems. If your child needs imaging that uses radiation, we use the lowest amount possible to produce the best image. We also have a 3D low-dose radiation X-ray machine, called the EOS, for safer full-body 3D images.
Complex conditions that affect your child’s bones, muscles and joints may affect other parts of their body too, from their nerves or lungs to their bladder. We connect you with the many types of Seattle Children’s experts your child needs – on the same day, in the same clinic whenever we can.
Symptoms of Amniotic Band Syndrome
The effects of amniotic band syndrome can vary widely. They depend on where the bands are and how early the bands formed during your baby’s development.
Your baby may have 1 or more of these:
- Creases, or indentations, around their finger, hand, arm, toe, foot or leg
- All or part of a limb missing
- Swelling (edema) because bands restrict the flow of blood or lymph
- A difference in the length of their arms or legs
- A gap (cleft) or other difference in their head, face, belly or chest
Diagnosing Amniotic Band Syndrome
Doctors can diagnose amniotic band syndrome by doing a physical exam when your baby is born. Your child may need an X-ray to see how a band affects deeper tissues under their skin. If a band is deep, your child may have an MRI (magnetic resonance imaging) scan or other imaging scan to see how the band affects their blood vessels and nerves.
Sometimes, but not usually, doctors can diagnose amniotic band syndrome based on what they see during an ultrasound before a baby is born. If this happens, talk with your healthcare team about what they can tell from the ultrasound and what it may mean for you and your baby. Our team at Seattle Children’s is happy to provide prenatal consultations to talk with you about your baby’s condition.
Treatment Options for Amniotic Band Syndrome
Treatment for amniotic band syndrome will be tailored to your baby and how the bands affect them.
If the bands are shallow and don’t cause any symptoms or health problems, your baby may not need any treatment. Even so, surgery may be an option to give the affected body part a more typical look.
Some babies need surgery – sometimes right after birth – to correct or prevent problems caused by the bands. The main concerns are that bands can reduce blood and lymph flow or press on nerves.
Surgery to Release Bands
If an amniotic band constricts a baby’s tissues, doctors perform surgery to release the band. The surgery requires careful work around the baby’s blood vessels and nerves. The exact method the surgeon uses will depend on details of your baby’s bands, like the number of bands, where they are and how deep and close they are.
Typically, the surgeon makes cuts (incisions) in the skin along the band. The surgeon removes extra or fragile skin that went down into the crease in your baby’s soft tissue.
Next the surgeon makes zigzag cuts in your baby’s skin above and below the band. This is called Z-plasty. It creates pointed flaps of skin. Then the surgeon gives a more normal contour to your baby’s soft tissue under the skin.
Finally, the surgeon brings the pointed flaps of skin together from above and below the band and closes the incisions. The zigzag method helps prevent scars that could restrict the tissue later. The doctor will want your child to come back for follow-up visits to make sure they are healing well.
The timing of surgery depends on the effects of the bands. Your baby may need urgent surgery in the days right after birth if:
- Bands press deeply on blood vessels or nerves
- They cause serious swelling (lymphedema) or other problems
If not, the doctor may recommend waiting to do surgery until your baby is at least 6 months old.
Most of the time, surgery for amniotic bands is done as day surgery. Based on how your baby is affected, they may need more than 1 surgery.
Other treatments will depend on your baby’s needs. They may include:
- Surgery to move affected bones into a better position (realignment surgery)
- Garments that apply pressure to control swelling (compression garments)
- Tools that help your child do things on their own (adaptive equipment)
- Prosthetics to replace missing body parts
If your baby has another condition linked to amniotic band syndrome – like syndactyly, clubfoot, cleft lip and palate or gastroschisis – they may need surgery or other treatment for this condition, too.
If you have questions about amniotic band syndrome treatment, call our Orthopedics and Sports Medicine Department at 206-987-2109. If you would like an appointment, ask your child’s primary care provider for a referral.
Providers, see how to refer a patient.