What is Amniotic Band Syndrome?

Amniotic Band Syndrome is a group of congenital birth defects believed to be caused by entrapment of fetal parts (usually a limb or digits) in fibrous amniotic bands while in utero.

In other words: Before the baby was born the body parts that shows signs of ABS (arm, fingers, toes, etc.,) were caught up and entangled in string-like bands. This caused abnormalities that were present at birth.

What is Amniotic Band Syndrome?

Thanks to the http://fetalcarecenter.org for use of this image.

What Causes Amniotic Band Syndrome?

Amniotic Band Syndrome is not genetic (i.e. not inherited). It is extremely unlikely that ABS will affect a future pregnancy. To date, no prenatal factors have been associated with ABS.

The commonly accepted view is that ABS occurs when the inner membrane (amnion) ruptures without injury to the outer membrane (chorion), this exposes the baby to fibrous sticky tissue (bands) from the ruptured amnion which can float in the waters of the uterus, these fibrous tissues can entangle the baby reducing blood supply and causing congenital abnormalities. In some cases a complete “natural” amputation of a digit(s) or limb may occur before birth or the digit(s) or limbs may be necrotic (dead) and require surgical amputation following birth.

A strong relationship between ABS and clubfoot exists. A 31.5% of associated clubfoot deformity and ABS can be correlated with 20% occurring bilaterally. Other abnormalities found with ABS include: clubhands, cleft lip, and/or cleft palate, and hemangioma.


Effects of Amniotic Band Syndrome

What is Amniotic Band Syndrome?

Evan’s hand following two surgeries

With Amniotic Banding no two cases are exactly alike. There are several features that are relatively consistent: syndactyly (webbed digits), distal ring constrictions, deformity of the nails, stunted growth of the small bones in the digits, limb length discrepancy, distal lymphedema (swelling), and congenital band indentations. If a band wraps tightly around a limb, the limb can actually be completely amputated. If the band is across the baby’s face it can cause cleft palate. In a large number of cases the baby is also born with clubfeet. ABS is also the cause of numerous miscarriages, such as when a band becomes wrapped around the umbilical cord.

In this photo of Evan’s hand you can see the banding line from his wrist to his pinky finger, he also has a banding line around the wrist. This photo is after two operations that separated his webbed fingers (syndactyly). His three fingers are small, with abnormal finger nails, and missing some joints, there is also some lymphedema (swelling at the joint) of the index finger middle joint. There is poor circulation in the ring finger as there were no major arteries in it at the time of surgery. Even on a hot July day, if you hold Evan’s hand you can feel how much colder this finger is then the rest of his hand.

Read some of the ABS stories to see how each case is different.


Amniotic Band Syndrome – Alternative Names

Some of these are different names for ABS and some are other syndromes that are often confused with ABS.  Misdiagnosis is apparently common.

  • Amniotic Deformity, Adhesions and Mutilations
  • Amniotic band disruption complex or sequence
  • Amniotic bands and sheets
  • Annular constriction bands
  • Congenital ring constriction
  • Constriction Band Syndrome  and Amniotic Constriction Band Syndrome
  • Intrauterine amputation
  • Streeter’s dysplasia
  • TEARS (The Early Amnion Rupture Spectrum)
  • Congenital Transverse Defects or Deficiency
  • Limb-body Wall Complex

Treatment Options

Treatment depends on which body part the band was wrapped around and the severity of the abnormality it caused.

  • In Utero Surgery - has been performed to free limbs from amniotic bands that threaten to amputate limbs.   Results of the first surgeries of this type were published in the “Journal of Ultrasound in Obstetrics & Gynecology.”  It is the first minimally invasive treatment to correct a non-lethal fetal condition.  Check out these links:
  • Treating Syndactyly - Evan had two plastic surgeries to separate his webbed fingers. A great description of syndactyly and what surgery does can be found at HandWorld
  • Treatment of Congenital Amputation - The War Amps has a great program called Matching Mothers to connect families with similar amputations.
  • Growing Hands -Distraction Augmentation Manoplasty – The technique pioneered by Dr.  Cowen “grows” up to one inch of bone per month to create palms and lengthen fingers. A strange looking contraption of steel rods, pins, and screws is inserted through the existing bone. Screws are turned at an even rate several times a day to achieve growth of up to one millimeter a day. Turning the screws takes up slack and the body responds to this stress by growing bone.
    • Botei. com – One of Dr. Cowen’s patients – Josefa’s history; a girl that was born with missing fingers and toes. Explains the long treatment to reconstruct the fingers of her hands.
  • Treating Clubfoot- The Clubfoot Club (my other site) A strong relationship between ABS and clubfoot exists. A 31.5% of associated clubfoot deformity and ABS can be correlated with 20% occurring bilaterally. Clubfeet are now treated non-surgically using the Ponseti Method