Amyoplasia in monochorionic monozygotic pregnancy following interstitial laser.

Amyoplasia is a specific form of arthrogryposis, without any genetic cause. Six to ten percent of amyoplasia cases are one of the monozygotic twins, with the other twin being normal. Failure of maturation of anterior horn cells (AHCs) due to ischemic injury has been postulated as the primary pathological change, leading to arrest in the development of muscle fibers supplied by the affected AHCs with the typical limb positioning seen in amyoplasia. Twin-to-twin transfusion syndrome (TTTS) is an important risk factor for ischemic injury in monozygotic twin pregnancies. We present a case of monochorionic diamniotic twin pregnancy with features of TTTS at 12 weeks who underwent interstitial laser followed by the development of lower limb akinesia in the surviving fetus. Possible causes of amyoplasia are discussed.