Achondroplasia

Symptoms:

• Typical appearance of achondroplastic dwarfism is apparent at birth
  • short stature
  • short limbs, proximal extremity (upper arm and thigh)
  • large appearing head
  • may be associated with clubfoot
  • skeletal (limb) abnormalities
  • Abnormal hand appearance (trident hand) with a three part hand made up of the thumb, second and third finger, and fourth and fifth finger; fingers 2 & 3 and 4 & 5 are separate.
  • marked kyphosis and lordosis (spine curvatures)
  • waddling gait
  • prominent (conspicuous) forehead (frontal bossing)
  • Marked curvature of the back
  • increased inward curve of lower back making the buttocks appear more prominent (lordosis)
  • increased outward curve of upper back making back appear slightly hunched (kyphosis)
  • head appears disproportionately large for body
  • hypotonia
  • polyhydramnios (present when affected infant is born)

Notes: A family history of achondroplasia should alert parents to the possibility of having an affected child. Typical appearance of achondroplastic dwarfism is apparent at birth.

Signs and tests:

Examination of the infant shows increased front-to-back head size (occipital-frontal circumference). There may be signs of hydrocephalus associated with enlargement of the chambers within the center of the brain (ventricular dilatation).

Tests that identify achondroplasia include:
X-rays of the long bones (see bone X-ray) can demonstrate achondroplasia in the newborn.