< 1.25 m in adult
1. Proportionate dysplasia
- mucopolysaccharidoses
- Morquio's, Hurler's, Hunter's
2. Dysproportionate dysplasia
- short trunk / SED
- short limb / achondroplasia & MED
Mucopolysaccharidoses
- Morquio's, Hurler's, Hunters
Cleidocranial Dysplasia
Severe OI
Severe Osteopetrosis
Hypophosphatasia
Hypophosphataemia
A. Short trunk
- SED
- Kniest's syndrome
- Metatropic dysplasia
B. Short limb
- Achondroplasia / Pseudoachondroplasia
- MED
- Diastrophic dysplasia
Rhizomelic - proximal
Mesomelic - middle
Acromelic - distal
Dysproportionate dwarfism
- short limbs, normal trunk
Characteristics
- coxa vara, genu varum
- radial and tibial bowing
- radial head dislocation
- metaphyseal flaring with inverted V shaped distal femoral physis
- Square iliac wings
Problems
- spinal problems i.e. stenosis
- coxa vara / genu varum
Dysproportionate dwarfism
- short limbs, normal trunk
Characteristics
- irregular delayed ossification at multiple epiphyses
Problems
- coxa vara, genu valgum
Dysproportionate dwarfism
- short trunk
Characteristics
- similar to MED but involves spine
Problems
- coxa vara / genu valgum
- spine (kyphoscoliosis / platyspondyly / ondontoid hypoplasia /atlanto-axial instability)
Characteristics
- metaphyseal changes with normal epiphyses
- can look like rickets
Problems
- coxa vara / genu valgum
Engelmann Disease
Characteristics
- diffuse sclerotic thickening of cortex
Trevor's Disease
Characteristics
- epiphyseal osteochondroma
- affects one joint only
- often ankle
- often medial
Proportionate dwarfism with complex sugars in urine
Morquio's syndrome
- AR
- presents 18 months to 2 years with waddling gait
- keratan sulphate in urine
- normal intelligence
Hurler's
Hunter's
Diaphyseal aclasia / multiple osteochondromas
Fibrous dysplasia
Ollier's
Maffucci's