Handbook of Genetic Counseling/Arthrogryposis

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Contracting[edit | edit source]

  • Acknowledge prior phone contact
  • What questions or concerns would you like to address today?
  • Overview of agenda for the session

Intake and Family History[edit | edit source]

  • Pregnancy and medical history
    • Maternal fever or viruses during pregnancy?
    • Oligohydramnios or unusually shaped uterus? (Crumply ears, thin or hyperextensible skin?)
    • Was the baby active throughout the pregnancy?
    • Any problems with hands, wrists, elbows, shoulders, knees, jaw, or back?
    • Any muscle weakness or hypotonia?
    • Has she had any muscle biopsies or other blood tests to rule out possible disorders?
  • Family history
    • Anyone else with club foot, joint dislocations, scoliosis?
    • Individuals who are short in stature?
    • Anyone with any muscular dystrophy, muscle disease, muscle weakness?
    • Anyone with cleft lip and/or palate, hearing loss, mental retardation?

Etiology[edit | edit source]

  • Condition describing the presence of multiple joint contractures at birth
    • Joint contractures are limitations in the range of motion of joints
    • May affect few or all joints to varying degrees
      • Includes hands, wrists, elbows, shoulders, hips, feet, and knees
      • Severe cases may include the jaw and back
  • Can be caused by anything that prevents normal joint movement before birth
    • When joint is not moved, extra connective tissue may grow around it and fix it in position
    • Tendons connecting to joint not stretched to normal length, making joint movement difficult
  • Four possible reasons for limitation of joint movement prenatally
    • Muscles do not develop properly (atrophy)
      • Muscle diseases, including congenital muscular dystrophies
      • Maternal fever during pregnancy
      • Viruses that damage cells transmitting nerve impulses to muscle
    • There is not sufficient room in the uterus for normal movement
      • Oligohydramnios
      • Abnormally shaped uterus that causes crowding
    • Central nervous system or spinal cord malformations
    • Tendons, bones, joints, or joint linings don't develop properly
  • May be environmental or genetic depending on cause of contractures
    • Genetic cause identified in about 30% of cases
    • Incidence is about 1 in 3000 live births

Causes of Arthrogryposis[edit | edit source]

  • Diagnosis usually made by ruling out other causes or syndromes
  • Cartilaginous abnormalities
    • Beal Syndrome
      • Linked to fibrillin locus on chromosome 5q23-31
      • Autosomal dominant
      • Crumpled ears, long slim limbs and fingers, frontal bossing, short neck
    • Antley-Bixer Syndrome
      • No confirmatory testing
      • Probably autosomal recessive
      • Crouzon syndrome-like appearance and midface hypoplasia
    • Distal Arthrogryposis Syndrome
      • Autosomal dominant with variable expression
      • Facial features usually normal
      • Arthrogryposis of hands and lesser extent feet
  • Physical constraint to movement
    • Oligohydramnios Sequence
      • Diagnosis made by clinical findings
      • Arthrogryposis usually involves knees and feet
      • Wrinkled skin, squashed nose, low-set ears, short neck
      • Often secondary to bilateral renal agenesis
    • Escobar Syndrome
      • Autosomal recessive condition
      • Thick skin folds keep joints in fixed position
      • Restrict joint motility in neck, axilla, antecubital, popliteal, and digital areas
  • Neurological Abnormalities
    • Trisomy 18 and Trisomy 13
      • Cause distal arthrogryposis
      • Causes severe mental retardation and facial dysmorphism
    • Smith-Lemli-Opitz
      • Autosomal recessive condition
      • Due to defect in cholesterol biosynthesis leading to severe MR and early death
      • Microcephaly, cryptorchidism, hypospadias, and arthrogryposis of hands
    • Zellweger Syndrome
      • Caused by genetic mutations at 7q11.23 and 1p22-21
      • Autosomal recessive inheritance
      • Severe hypotonia, brachycephaly, open fontanels, cryptorchidism, hypospadias, and distal arthrogryposis
    • Infantile Spinal Muscular Atrophy
      • Autosomal recessive and X-linked inheritance
      • Arthrogryposis occurs in 10-20% of neonates with SMA
    • Moebius Syndrome
      • Sporadic or autosomal dominant in some cases
      • Causes bilateral facial weakness and arthrogryposis in about 30% patients
    • Congenital Myotonic Dystrophy
      • Due to trinucleotide repeat expansion at 19q13
      • Autosomal dominant disorder
      • Marked body and facial hypotonia with arthrogryposis in lower extremities
    • Congenital Muscular Dystrophy
      • Inheritance pattern varies depending on type of muscular dystrophy
      • Hypotonia, muscle weakness, and distal arthrogryposis
      • Serum creatine kinase may be normal or elevated

Clinical Manifestations and Natural History[edit | edit source]

  • Wide variation in degree to which muscles and joints are affected
    • May be accompanied by other conditions tat complicate the picture
    • Outlook is generally very positive
  • Not a progressive condition
    • Substantial improvements seen with treatment
    • Most individuals are of normal intelligence and lead independent lives as adults
  • Possible features
    • Head and neck
      • Facial asymmetry
      • Micrognathia, notched chin, or malar hypoplasia
      • Immobile facies
      • Low-set posteriorly located ears or overfolded helices
      • High nasal bridge
      • Highly arched palate, cleft lip, or cleft palate
      • Eyes
        • Keratoconus
        • Downslanting palpebral fissures
        • Blepharoptosis, hypertelorism, or ophthalmoplegia
        • Retinopathy
      • Short neck, fused cervical vertebrae, and pterygia
    • Chest deformities
    • Inguinal hernia
    • Hand and foot
        • Overlapping fingers, tapered fingers, camptodactyly, or syndactyly
      • Clenched fists
      • Positional foot deformities or clubfoot
      • Single or bridged palmar creases
      • Absent or hypoplastic distal flexion creases
    • Extremities
      • Radial head dislocation, contractures, and limitation of motion
      • Affects shoulder, elbow, wrist, knee, ankle, and hip joints
    • Scoliosis and kyphosis
    • Microphallus and cryptorchidism
    • Elevated serum creatine phosphokinase
  • Occasional growth and mental retardation

Treatment/Management[edit | edit source]

  • First important to determine the cause
    • Influences prognosis, recurrence risk, and treatment
      • Definite diagnosis may not be possible in neonatal period
      • Important to separate neurological from non-neurological causes
    • MRI study for infants with neurological findings suggesting brain or spinal cord involvement
    • Chromosome analysis or genetic testing for those who appear to have genetic syndrome
  • Physical therapy
    • Helps improve muscle strength and range of motion
    • Includes stretching, strengthening, mobility training, and training in ADL skills
  • Casting or splinting
    • Splints can augment stretching to increase range of motion
    • Casting can improve foot position
    • Removable splint such as bi-valve cast or wearing splint at night often still allows motion and stretching
  • Surgeries
    • Usually considered supportive measure to other forms of treatment
    • Performed on ankles to put feet in weight-bearing position
    • Tendon transfers can sometimes improve muscle function

Psychosocial Issues[edit | edit source]

  • Parental concern over underlying cause of condition
  • Reaction to infant requiring braces, casts, or surgeries
  • Difficulty bonding with a child who looks different or requires special care
  • Guilt, depression, anger over new diagnosis
  • Concern for child's future

Support Resources[edit | edit source]

  • National Support Group for Arthrogryposis
Web: [1]
Email: info@avenuesforamc.com
  • NORD (National Organization of Rare Disorders)
Web: [2]

Arthrogryposis Multiplex Congenita Support Inc.

Web: [3]

References[edit | edit source]

  • Alfonson I, et al. "Arthrogryposis Multiplex Congenita." International Pediatrics (2000) 15:4;197-204.
  • "Arthrogryposis Multiplex Congenita." Multiple Congenital Anomaly/Mental Retardation Syndromes: US National Library of Medicine. http://www.nlm.nih.gov
  • "What is Arthrogryposis?" Published by AVENUES. http://www.avenuesforamc.com

Notes[edit | edit source]

The information in this outline was last updated in 2002.