Arthrogryposis Multiplex Congenita (AMC)

Reports from the MHC data base

Report from the Questionnaire (PDF)
Report from the Observation Chart (PDF)

Codes

ICD-10: Q74.3
ORPHA: 1037

Estimated occurrence

1:4 500 live births

Etiology

There are more than 150 different diseases within this diagnosis and the genetic cause varies. The etiology may be classified as:

  • Muscular causes (various congenital muscular diseases).
  • Neurogenic causes (deformities of the central nervous system, loss of motor neurons in the spinal marrow, loss of peripheral nerves).
  • Connective tissue diseases.
  • Reduced mobility of the fetus owing to insufficient space in the uterus (lack of amniotic fluid, twin pregnancy, heart-shaped uterus).
  • Maternal illness during pregnancy.

General symptoms

Stiffness in several joints is the common denominator. The disease is not progressive; on the contrary treatment may result in improvement. It is common for these children to be born with one dislocated hip and a club foot.

Orofacial/odontological symptoms

The jaw-joints may also be affected, which results in a restricted ability to open the jaws. An overjet and open bite in the region of the front teeth, a narrow, high palate and a small lower jaw all occur. Many individuals have restricted oral motor skills, which affects their ability to suck, chew, swallow, and speak. Drooling and teeth grinding occur frequently.

Orofacial/odontological treatment

  • It is important that individuals with this diagnosis receive dental preventive treatment, with extra prophylactic care and information on oral hygiene from an early age.
  • When the jaws do not open properly, the function of the jaw joint should be investigated, and appropriate treatment thereafter prescribed (such as jaw-stretching exercises or surgery).
  • Regular check-ups of dental and jaw development. Orthodontist should be consulted when needed.
  • Teeth grinding should be followed up, and be managed with a splint when necessary.
  • Training in oral motor skills and extra stimulation in cases of eating disorders, speech difficulties and drooling.

Sources

  • The MHC database - The Mun-H-Center database on oral health and orofacial function in rare diseases.
  • The Documentation from the Ågrenska national competence centre for rare diseases.
Updated: 2017-09-12 13:37