In the predominant facial form, called Nager acrofacial dysostosis, the
facial changes resemble strikingly those of the Treacher Collins syndrome:
malar hypoplasia, maxillomandibular hypoplasia, cleft lip or palate,
conductive hearing loss, and radial limb hypoplasia. Neonates may present
respiratory or feeding problems because of severe mandibular hypoplasia.
Upper limb malformation is a constant feature of Nager syndrome and ranges
from thumb hypoplasia to the absence of the radial ray. Intelligence is
usually normal. Neurologic: Hydrocephalus, agenesis of corpus callosum, polymicrogyria,
and spinal cord defects are reported. Airway: Absence of zygomatic arches associated
with hypoplastic malar region and frequent hypoplasia of the larynx and
epiglottis may contribute to the respiratory distress often observed in
these infants. Cardiac: Association with congenital heart defect is rare.
Musculoskeletal: Short stature, hypoplastic or aplastic radius, radioulnar synostosis.
Limited elbow extension. The presence of a hypoplastic or aplastic thumb is
almost characteristic of this condition. Other features include syndactyly,
clinodactyly, or camptodactyly. The humeri are often shortened. Cervical
vertebral deformities are frequent. Visceral: Association with Hirschsprung
disease has been suggested.