Amniotic Band Syndrome

  • Etiology: wide variety of deformities depending on what parts are trapped by amnion, exogenous theory – disruption of amnion early in pregnancy allows embryo/fetus/fetal parts to enter chorionic cavity and become tangled / entrapped by proteinaceous bands which disrupt tissue growth, endogenous theory – vascular insult
  • Imaging: asymmetric pattern, single or multiple defects
    — Head/face entrapment – acrania, aneencephaly, facial clefts, nasal deformities, asymmetric microphthalmos
    — Truncal entrapment – abdominal wall defects, rib clefting, congenital scoliosis, ambiguous genitalia, imperforate anus
    — Extremity entrapment – variable levels of limb amputation, variable levels of limb constriction with possible distal atrophy, lymphedema distal to the level of band constriction, clubfoot, phocomelia

Radiology Cases of Amniotic Band Syndrome

Radiograph of hand in amniotic band syndrome
AP radiograph of the hand shows the presence of the first proximal phalanx. All the other phalanges are absent.