Arthrogryposis multiplex congenita (AMC) is a frequent sequence of congenital joint fixation. The major cause of arthrogryposis is fetal akinesia (decreased fetal movements), which could result from fetal abnormalities (e.g., neurogenic, muscle, and connective tissue abnormalities) or maternal disorders (e.g., infection, drugs, and trauma). AMC is characterized by reduced mobility of many joints of the body due to the overgrowth of fibrous tissue in the joints (fibrous ankylosis). The symptoms of arthrogryposis multiplex congenita vary widely among affected individuals depending on the disease type. In the most common form of the disease, the range of motion of the joints in the limbs is limited or fixed.
The disease occurs in 1/3000 live births and has been ascribed to either oligohydramnios or a variety of diseases involving the central nervous system, skeletal muscle, or spinal cord. Since neuronal degeneration and neuronophagia occur in the anterior horns, it has been hypothesized that the AMC of neurogenic origin could be related to acute spinal muscular atrophy (SMA type I, Werdnig-Hoffmann disease). Life span is usually normal, but it may be depend on the disease severity and associated malformations.