Metaphyseal Chondrodysplasia

Characteristics

 

Short limbed dwarfism, normal trunk and spine

 

Metaphyseal changes of tubular bones

- normal epiphyses

- metaphysis adjacent to physis very broad and mildly scalloped

- resembles healing rickets

 

X-ray

 

Metaphyseal chondrodysplasia hipsMetaphyseal chondrodysplasia

 

Sclerosing bone deformity

- usually incidental finding on xray

 

Erlenmeyer Flask Deformity

 

Pathology

 

Defect in proliferative and hypertrophic zones of physis

Autosomal recessive

 

Types:

 

Jansens (Rare)

- most severe

- defect PTHrP (AD)

- extensive calcification

- retarded

- very short

- striking bulbous metaphyseal expansion long bones

 

Schmid's

- more common, less severe

- present later (AD)

- defect type X collagen

 

McKusick

- associated immune defects

 

Clinically

 

Hips

- coxa vara

 

Knees

- genu valgum

 

DDx

 

Rickets

- normal blood tests

 

Metaphyseal Dysplasia

AKA Pyle's Disease

 

No dwarfism (c.f. chondrodysplasia)