Fetal surgery of extremity amniotic bands: An experimental model of in utero limb salvage in fetal lamb

BACKGROUND: Extremity amniotic band (EAB) syndrome can cause an intrauterine amputation as a result of a mechanical effect with progressive strangulation. The aim of the study is to assess the use of fetal surgery of EABs with risk of amputation in the ovine fetus. METHODS: Right limbs of fifteen 60-day-gestational age fetal sheep were ligated with silk suture at the infracondylar level. Left limbs were used for paired comparison. Fetuses were randomized into 3 groups: an early-repair group (n = 5), a late-repair group (n = 5), and a nonrepaired group (n = 5). The limbs of the 2 repaired groups underwent fetal release. The limbs obtained from at-term fetuses were analyzed morphologically, functionally, and radiologically. Statistical analysis with paired test was used to compare data. RESULTS: Nonrepaired limbs showed amputation or quasi amputation; the repaired ones did not. However, those late-repaired had significantly reduced passive ankle range of motion, shorter limb length, and mild residual changes. CONCLUSIONS: Intrauterine release of potentially severe EABs prevents limb amputation and leads to morphofunctional recovery. Early release shows better results. CLINICAL RELEVANCE: Intrauterine amputations caused by EABs in the human fetus might be avoidable by fetal surgery. LEVEL OF EVIDENCE: Level of evidence II.