Arthrogryposis: Joint contractures that develop before birth and are evident at birth. With arthrogryposis there is a lack of the normal range of motion in one or more joints. In normal embryonic development, joints can be seen moving by 8 weeks of gestation. This motion of joints is essential to the proper development of the joints and structures around them. Limitation of joint motion before birth leads to joint contractures and arthrogryposis. Prenatal limitation of joint mobility can result from neurologic deficits, muscle defects, connective tissue defects, and fetal crowding (in which there is not enough room for the fetus to move around freely in the womb).