Autosomal dominant osteochondrodysplasia.
Synopsis
short-limb dwarfism identifiable at birth
craniofacial anomalies
- large head
- depressed nasal bridge
- frontal bossing
- megalencephaly
- midface hypoplasia
- recurrent otitis media in infancy and childhood
- conductive hearing loss
- low nasal bridge
- foramen magnum stenosis
trunk anomalies
- narrow chest
- upper airway obstruction
- normal trunk length
- platyspondyly
- vertically shortened small square ilia (Rx)
- lumbar kyphosis in infancy
- exaggerated lumbar lordosis during childhood and adulthood
- congenital spinal stenosis due to short pedicles, especially lumbar
- progressive interpediculate narrowing in lumbar spine
- dysplastic ilium
- narrow sacroiliac groove
limb anomalies
- limb rhizomelic shortening
- short limb bones with metaphyseal flaring
- generalized joint laxity
- flat rooted acetabulae
- bowing of legs
- rhizomelic shortening
- rhizomeli dwarfism
- short femoral neck
- short femora (femoral shortening)
- metaphyseal flaring
- limited elbow and hip extension
- brachydactyly
- trident hand
- hydrocephalus, occasional
- hypotonia in infancy and early childhood
- small foramen magnum
- brain stem compression
- cevical cord damage
- cardiac arrhythmia
delayed motor development
Microscopy
heterozygous achondroplasia
- well-organized physeal plate
- retarded physeal plate
homozygous achondroplasia
- markedly retarded and dosrganized physeal plate
Etiology
FGFR3 germline mutations
- 80% cases new mutations
- 99+% of the mutations are FGFR3, G380R (134934.0001)
- Paternal age effect
Case records
See also