Arthrogryposis Multiplex Congenita

Arthrogryposis multiplex congenita (AMC) is a multietiologic congenital syndrome resulting from decreased fetal movement and defined by joint contractures involving 2 or more body regions. The 6 major etiologic categories include neuropathic abnormalities, muscle abnormalities, connective tissue abnormalities, uterine space limitations, intrauterine vascular compromise, and maternal disease. Prenatal US most commonly detects joint contractures during the second or third trimester, although first-trimester findings such as increased nuchal translucency or congenital anomalies may suggest the diagnosis earlier. In cases where fetal movement is not assessed, diagnosis may be delayed until birth. Careful attention to imaging findings is essential when evaluating any pregnancy in which decreased fetal movement is reported or AMC is suspected.