A typical baby with Arthrogryposis

Arthrogryposis, describes congenital joint contracture in two or more areas of the body. It derives its name from Greek, literally meaning "curving of joints" (arthron, "joint"; grȳpōsis, late Latin form of late Greek grūpōsis, "hooking").

Children born with one or more joint contractures have abnormal fibrosis of the muscle tissue causing muscle shortening, and therefore are unable to perform active extension and flexion in the affected joint or joints.

AMC has been 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. Types of arthrogryposis with a primary neurological or muscle disease belong to the syndromic group.

Signs and Symptoms

Often, every joint in a patient with arthrogryposis is affected; in 84% all limbs are involved, in 11% only the legs, and in 4% only the arms are involved.[4] Every joint in the body, when affected, displays typical signs and symptoms: for example, the shoulder (internal rotation); wrist (volar and ulnar); hand (fingers in fixed flexion and thumb in palm); hip (flexed, abducted and externally rotated, frequently dislocated); elbow (extension and pronation) and foot clubfoot and less commonly congenital vertical talus. Range of motion can be different between joints because of the different deviations. Some types of arthrogryposis like amyoplasia have a symmetrical joint/limb involvement, with normal sensations. The 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.

Intelligence is normal to above normal in children with amyoplasia, but it is not known how many of these children have an above normal intelligence, and there is no literature available about the cause of this syndrome. There are a few syndromes like the Freeman-Sheldon and Gordon syndrome, which have craniofacial involvement. The amyoplasia form of arthrogryposis is sometimes accompanied with a midline facial hemangioma. Arthrogryposis is not a diagnosis but a clinical finding, so this disease is often accompanied with other syndromes or diseases. These other diagnoses could affect any organ in a patient. 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.

Causes

Research of arthrogryposis has shown that anything that inhibits normal joint movement before birth can result in joint contractures. Arthrogryposis could be caused by genetic and environmental factors. In principle: any factor that curtails fetal movement can result in congenital contractures. The exact causes of arthrogryposis are unknown.

Diagnosis

Research on prenatal diagnosis has shown that a diagnosis can be made prenatally in approximately 50% of fetuses presenting arthrogryposis. It could be found during routine ultrasound scanning showing a lack of mobility and abnormal position of the foetus. There are other options for visualization of details and structures using techniques such as 4D ultrasound. In clinic a child can be diagnosed with arthrogryposis with physical examination, confirmed by ultrasound, MRI, or muscle biopsy.

Treatment

The treatment of arthrogryposis includes occupational therapy, physical therapy, splinting and surgery.[3] The primary long-term 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.[3] Only a few good articles exist in which a surgical technique that is used to treat arthrogryposis is described. These surgeries are explained below.

Epidemiology

Arthrogryposis is a rare condition. Some authors say the overall prevalence is one in 3000 and others say it is one in 11000-12000 among European live births. Congenital clubfoot is the most common single contracture and its prevalence is one in 500 live births.



References