Unusual presentation of amniotic band syndrome

ABS refers to a spectrum of asymmetric nonembryologic disruptive abnormalities of various fetal parts involving limbs, the craniofacial region, and the trunk attributed to fibrous bands. Most authors agree with the hypothesis elaborated in 1968 by Torpin, who thought that ABS was caused by antenatal rupture of the amnion, leading to entrapment of fetal parts by fibroid bands. The prevalence of ABS is one in 1300 live births and is considered a sporadic event. Prenatal diagnosis of cases of ABS made in the past was based on sonographic visualization of either amniotic sheets or bands associated with fetal deformities. Although most of the anomalies associated with ABS are presented as a disruption of fetal body parts, including ring constriction of limbs, abdominal wall defects, anencephaly, encephalocele, calvarial and facial defects, scoliosis, and spina bifida, ABS infrequently has a different picture. We report on a rare and unusual case of ABS diagnosed at 16 weeks' gestation, causing extreme exaggeration of cervicothoracic lordosis.