Review Question - QID 219779

In a patient with syndactyly (Figure A), clubfoot, and cleft lip/palate, amniotic band or constriction syndrome is the most likely associated condition from the answers listed (Answer 3).

Amniotic band syndrome (ABS) or constructive ring syndrome is a condition in which the amniotic membrane is disrupted, releasing free strands of amniotic tissue that can potentially adhere to, encircle, or even strangulate portions of the extremities, leading to appendage hypoplasia, syndactyly, or amputation. The distal extremities are frequently affected, with the hand being one of the most common locations. ABS is associated with syndactyly, clubfoot, cleft lip/palate, craniofacial defects, cardiac defects, and encephalocele. Due to highly varied presentations, treatment must be tailored to each individual.

Moran et al. completed a review detailing the diagnosis and management of ABS in the upper extremity. They concluded that the hand is the most commonly affected area, representing 55% or 200 of the 364 patients in their review. Additionally, they analyzed finger involvement and found that the long finger is most commonly affected (28%). However, the index and ring fingers are also frequently compromised 23% and 27% of the time, respectively. Ultimately, ABS is a nonfamilial condition that can cause debilitating limb malformations, and are associated with lymphedema and neurovascular compromise.

Foulkes et al. reviewed 71 cases of ABS, detailing birth year, sex, ethnicity, gestational and family histories, concurrent diagnoses, anatomic patterns of involvement, functional impairments, and surgical interventions. They concluded that, on average, patients had three affected limbs, with the most frequent expression occurring in the distal central digits of the upper extremities. Additionally, they found that 60% had abnormal gestational histories, 50% had concurrent diagnoses, and nearly one-third had clubfeet. Patients averaged 20% whole-body impairment and underwent approximately three reconstructive procedures, including distraction osteogenesis and free osteocutaneous transfer.

Figure A: This is a clinical image depicting syndactyly of the left foot

Illustration A: This is a pictorial representation demonstrating the incidence of extremity or digit involvement in ABS

Incorrect answers:
Answer 1, 2, 4, 5: These conditions are not associated with amniotic band syndrome.