Arthrogryposis Multiplex Congenita (Amyoplasia Congenita)

Key Features

• Consists of incomplete fibrous ankylosis (usually bilateral) of many or all joints of the body

• Affects both sexes equally and occurs in approximately 1 in 2000–3000 live births

Clinical Findings

• Upper extremity contractures usually consist of

  • Adduction of the shoulders

  • Extension of the elbows

  • Flexion of the wrists

  • Stiff, straight fingers with poor muscle control of the thumbs

• Common deformities of the lower extremities include

  • Dislocation of the hips

  • Extension contractures of the knees

  • Severe club feet

• Joints are fusiform and the joint capsules are decreased in volume due to lack of movement during fetal development

• Muscle development is poor and may be represented only by fibrous bands

Diagnosis

• Clinical

Treatment

• Passive mobilization of joints is the early treatment

• Removable splints combined with vigorous therapy are the most effective conservative treatment

• However, surgical release of the affected joints is often necessary

• Clubfoot associated with arthrogryposis is very stiff and nearly always requires surgical correction

• Knee surgery, including capsulotomy, osteotomy, and tendon lengthening, is used to correct deformities