What is Arthrogryposis?

Arthrogryposis multiplex congenital (AMC) is the congenital joint contracture in two or more areas of the body. “Arthrogryposis” comes from Greek, meaning "curving of joints." Children born with joint contractures have abnormal fibrosis of the muscle tissue, causing muscle shortening, and are unable to perform active extension and flexion in the affected joint or joints. Arthrogryposis is divided into three groups: amyoplasia, distal arthrogryposis, and syndromic. Amyoplasia is characterized by severe joint contractures and muscle weakness. Distal arthrogryposis mainly involves the hands and feet. Neurological or muscle disease forms of arthrogryposis are in the syndromic group.

What is Arthrogryposis?

Those with arthrogryposis often have every joint affected. In 84 percent, all limbs are involved; in 11 percent only the legs are involved; and, in 4 percent only the arms are involved. When affected, joints display typical symptoms. Range of motion can be different between joints because of the different deviations. Contractures in the joints can result in delayed walking development in the first 5 years, but severity of contractures do not necessarily predict eventual walking ability or inability. There are a few slightly more common diagnoses such as pulmonary hypoplasia, cryptorchidism, congenital heart defects, tracheoesophageal fistulas, inguinal hernias, cleft palate, and eye abnormalities

Arthrogryposis Causes

Any factor that curtails fetal movement may result to congenital contractures and arthrogryposis. However, its exact causes are unknown.

• Extrinsic factors: The malformations of arthrogryposis can be secondary to environmental factors such as decreased intrauterine movement, oligohydramnios (low volume or abnormal distribution of intrauterine fluid), and defects in the fetal blood supply.
• Intrinsic factors: Molecular, muscle- and connective tissue development disorders or neurological abnormalities.
• Molecular basis: More than 35 specific genetic disorders are associated with arthrogryposis. Most of those mutations are missense, which means the mutation results in a different amino acid.
• Muscle and connective tissue development disorders: A loss of muscle mass with an imbalance of muscle power at the joint can lead to connective tissue abnormality, causing joint fixation and reduced fetal movement.
• Neurological abnormalities: Up to 80 percent of the cases of the most severe forms of arthrogryposis are caused by neurological abnormalities, which can be either genetic or environmental.

Arthrogryposis Diagnosis

Diagnosis can be made prenatally in approximately 50 percent of fetuses with arthrogryposis. Routine ultrasounds can display a lack of mobility and abnormal positions of the fetus. A child can be diagnosed with arthrogryposis via physical examination, confirmed by ultrasound, MRI, or muscle biopsy.

Arthrogryposis Prognosis

Arthrogryposis is non-progressive, so with proper medical treatment, health can be stable or improve. Arthrogryposis cannot be cured, but with proper treatment, most children make significant improvements in their range of motion and ability to move their limbs, enabling full lives. Surgical intervention may also improve joint mobility and function.

Arthrogryposis Treatment

Arthrogryposis treatment includes occupational therapy, physical therapy, splinting, and surgery. The goals of these treatments are increasing joint mobility, muscle strength, and the development of adaptive use patterns that allow for walking and independence with activities of daily living. Since arthrogryposis includes many different types, the treatment varies between patients depending on the symptoms. Surgical techniques may also be used.

Mobility for Arthrogryposis

Some with arthrogryposis have difficulty walking, requiring a power wheelchair. Quantum Rehab® manufactures technologically-advanced power wheelchairs that meet the needs of those living with arthrogryposis.

Quantum’s TRU-Balance® 3 seating is adaptable to address individual seating needs, including contractures. Its drive controls can be mounted wherever needed for access by the user. These features and more allow Quantum to custom tailor a power chair to an individual’s arthrogryposis mobility needs.

For more information on Quantum’s unique power chair technologies, please click here.