Arthrogryposis multiplex congenita is a collective term applied to a very large number of different syndromes characterised by non-progressive, multiple joint contractures present at birth.1 The joints usually develop normally in early embryonic life but as gestation progresses, movements are required to facilitate normal development. Where there are abnormalities that prevent this from occurring, such as neurological or connective tissue disorders or physical restriction, the condition forms. The muscles involved are partially or completely replaced by fat and fibrous tissue. The commonest form accounting for 40% of cases is amyoplasia.
Other associated problems include polyhydramnios, pulmonary hypoplasia, micrognathia, ocular hypertelorism and a short umbilical cord.
Epidemiology: It may occur to some extent in 1 in 3,000 live births. The condition is usually detected at birth or before by ultrasound examination. It is often secondary to other conditions. If they are X-linked this will produce a male preponderance but otherwise there is an equal sex incidence.
Causes: It can be due to environmental causes like lack of ability to move, single gene conditions or as part of a more complex disorder.2 There are 7 types of distal arthrogryposis classified as type I, type II and types IIA to IIE. Underlying neurological or myopathic disorders are very common.3
History can be examined in terms of family history, pregnancy and delivery:
Ask about family history of:
- Other affected children or members of the family
- Consanguinity increases the risk of rare recessive disorders
- Increasing parental age may increase risk, both mother and father
- A parent may have a mild form or have had infantile contractures
- Ask about miscarriages, possibly with fetal abnormalities
- Ask about maternal disease. This may include myotonica dystrophica that can produce a very severe condition but also myasthenia gravis and multiple sclerosis
Ask about the pregnancy and delivery:
- Infection with some viruses, including rubella and coxsackie can cause neuropathy
- Prolonged maternal pyrexia can produce contractures due to abnormal nerve growth and migration. This can also be produced by very hot baths, hot tubs and saunas in pregnancy.
- Drugs, including phenytoin and alcohol can impair fetal movements
- Oligohydramnios reduces fetal movements. A septate uterus or large fibroids can do the same
- An abnormal lie is common and this will complicate delivery
- There may have been amniotic bands or placental abnormality. A short cord or wrapped around a limb reduced mobility
- Multiple pregnancy restricts room to move
Examination Classical presentation of amyoplasia shows involvement of both upper and lower extremities with the lower extremities typically more involved. Abnormalities can include:
- Shoulders (adduction, internal rotation)
- Elbows (extension or fixed flexion)
- Wrists (deviation)
- Deformity of thumb and palm and rigid interphalangeal joints
- Hips (with dislocation of one or both sides)
- Knees (fixed extension or flexion)
- Rigid bilateral clubfeet /vertical tali
Other characteristic features include:
- Thin subcutaneous tissue and absent skin creases
- Symmetrical deformities, becoming more severe distally
- Rigid joints
- Congenital dislocation of the hip and sometimes knees too
- Atrophy or absence of groups of muscles
- Normal sensation
- Contractures, especially of distal joints
- Deformities of the limbs include pterygium, shortening, webs, compression often due to cord wrapping, absent patellae, dislocated radial heads, and dimples.
- Deformities of face and jaw include asymmetry, a flat nasal bridge, haemangioma, micrognathia and trismus.
- Scoliosis, genital deformity and umbilical or inguinal herniae are common
- There may be many other malformations of the skeleton, respiratory tract, urinary system and nervous system
- X-rays of all joints may show bony abnormalities including missing bones, skeletal dysplasias, scoliosis, ankylosis and fractures arising from difficult delivery. X-ray of spine and pelvis should always be included
- Ultrasound, CT and MRI may all be useful to assess muscle mass and abnormalities in other tissues like central nervous system
- If muscles are very flaccid, blood test for creatinine kinase may be revealing. Antiviral antibody may also show a cause
- Cytogenetic studies may be required
Management Physical therapy to improve the range of motion in and stretch surrounding tissues is very useful, especially in amyoplasia and distal arthrogryposis although in diastrophic dysplasia it may lead to ankylosis instead. It should be stared early.4 Splinting between times can correct deformity, especially in hands and wrists. Serial casting after physical therapy has achieved maximum usefulness with weekly changes of cast and gentle manipulation.5
Surgery is often needed to correct soft tissue contractures and joint deformities. It can also reduce and stabilise dislocated hips, correct foot deformities and stabilise spinal deformities. Anaesthesia can be a problem as some patients with are forms of arthrogryposis have malignant hyperpyrexia too.
Prognosis: About 50% with limb abnormalities from CNS disease die in the first year of life. Scoliosis is common and can appear at any age but needs correction before it becomes severe. The long term prognosis in terms of dependency is poor in many cases but for amyoplasia it is quite reasonable.6
- Hall JG; Genetic aspects of arthrogryposis.;Clin Orthop Relat Res 1985 Apr;(194):44-53.[abstract]
- Gordon N; Arthrogryposis multiplex congenita.;Brain Dev 1998 Oct;20(7):507-11.[abstract]
- Banker BQ; Neuropathologic aspects of arthrogryposis multiplex congenita.;Clin Orthop Relat Res 1985 Apr;(194):30-43.[abstract]
- Bernstein RM; Arthrogryposis and amyoplasia.;J Am Acad Orthop Surg 2002 Nov-Dec;10(6):417-24.[abstract]
- Smith DW, Drennan JC; Arthrogryposis wrist deformities: results of infantile serial casting.;J Pediatr Orthop 2002 Jan-Feb;22(1):44-7.[abstract]
- Sells JM, Jaffe KM, Hall JG; Amyoplasia, the most common type of arthrogryposis: the potential for good outcome.;Pediatrics 1996 Feb;97(2):225-31.[abstract]
- Chen H Arthrogryposis from emedicine
- www.tagonline.org.uk/ The Arthrogryposis Group, patient support
Acknowledgements EMIS is grateful to Dr Paul Hewish for updating this record from a original by doctoronline.nhs.uk. The final copy has passed peer review of the independent Mentor GP authoring team. ?EMIS 2005.