Non-lethal arthrogryposis multiplex congenita presenting with cystic hygroma at 13 weeks gestational age.

Arthrogryposis is defined as multiple joint contractures, the aetiology of which is variable. Prenatal diagnosis has focused on diminshed fetal movement and detection of joint contractures on ultrasound. These findings usually do not become evident until 16 to 18 weeks of gestation. Although others (Baty, 1989; Hyett et al., 1997) have reported the diagnosis of arthrogryposis in the first and early second trimester by the presence of nuchal oedema, these reports have all focused on lethal conditions. We report on two female siblings with non-lethal arthrogryposis multiplex congenita. The diagnosis was suspected in the second pregnancy at 13.5 weeks when a large cystic hygroma was detected on ultrasound. Multiple joint contractures became evident at 18 weeks. We hypothesize that the aetiology may be secondary to delay in lymphatic maturation with development of a large cystic hygroma resulting in restriction of fetal movement during early joint formation. Further, the fact that the two female siblings had a similar pattern of facial and joint development, and that their parents are second cousins, suggests an autosomal recessive basis for this form of AMC.