Arthrogryposis can be literally translated from Greek as meaning, “curved joint”. The term encompasses a group of rare conditions that include joint contractures and often muscles that are developed abnormally. The severity can range from minor joint stiffness to the type where almost all the joints are involved. It typically affects the joints symmetrically and usually all extremities are affected in some variation. Muscles are usually weak, which further restricts movement.
The exact cause is not known. It is proposed that it may be failure of the nervous system to develop properly or a result of some type of obstruction that restricts movement of the fetus during development. Others hypothesize that decreased amniotic fluid or hyperthermia in utero may play a part. It is not considered a hereditary disease and yet a genetic cause is identified in about 30% of all cases.
Statistically it is a rare disease. In the United States, approximately 1 in 3,000 babies are born with arthrogryposis. It is more common in areas in the world that are isolated. Finland and the Bedouins in Israel are among two such populations.
There is no definitive method for diagnosing the disorder. It cannot be detected before birth, but is instead diagnosed in infants based on muscle biopsy, blood tests and other findings that help provide evidence while ruling out other disorders. The most common symptoms involve restricted movement in the shoulders, elbows, wrists, hands, hips, knees and feet. Scoliosis may be present, the face and jaw may be affected and growth may be delayed.
Hip and knee dislocation may be present, rigid joints and atrophy of the muscles or tendons which draw extremities into contracted positions. The hands and feet are typically more affected than the other joints. There is no loss of sensation, but deep tendon reflexes are often decreased or absent.
Treatment includes physical therapy to stretch and strengthen the muscles and occupational therapy to improve fine motor skills and help with activities of daily living. Splints may be worn at night to stretch the joints. Sometimes orthopedic surgery can correct more severely affected joints or tendon surgery may be done to improve mobility. Surgery is usually chosen if the result is expected to improve quality of life.
The disorder does not include any speech or cognition issues. Life span is usually expected to be normal depending on the severity of the deformities, the presence of any heart defects, central nervous system damage and whether or not it affects respiratory function. It affects both males and females equally and does not correlate with race.
It is not progressive. Therefore, the prognosis is that most individuals will be able to live an independent and productive life. Many famous people have had forms of arthrogryposis including activists, musicians, artists and athletes. Most individuals thrive despite the physical restrictions. For more information, contact Arthrogryposis Multiplex Congenita Support, Inc.