Achondroplasia
Definition
Dysproportionate dwarfism
- short limbs and normal trunk
- rhizomelic
DDx
- physeal dysplasia (SED, MED)
Aetiology
FGF Receptor 3
- point mutation
- decreases endochondral ossification
- normal intramembraneous ossification
- FGFR3 is found in all pre-bone cartilage & in CNS
- FGFR3 inhibits chondrocyte proliferation in the proliferative zone