- Achondroplasia
- Asphyxiating thoracic dystrophy
- Campomelic dysplasia
- Chondrodysplasia punctata
- Chondroectodermal dysplasia
- Diastrophic dysplasia
- Mucopolysaccharidoses
- Pyknodysostosis
- Spondyloepiphyseal dysplasia
- Thanatophoric dysplasia
Approach to the DDX of skeletal dysplasias:
- Definition
— A skeletal growth disturbance of bone growth and structure that results in overall short stature
— Shortening of limbs or spine below third percentile for normal newborn - Types of limb shortening
— Rhizomelic – proximal appendicular skeleton – humerus, femur
— Mesomelic – middle appendicular skeleton – radius-ulna, tibia-fibula
— Acromelic – distal appendicular skeleton – metacarpals, metatarsals, phalanges
— Micromelic – entire appendicular skeleton - Lethal skeletal dysplasias due to short ribs leading to thoracic dysplasia
— Rhizomelic – thanatophoric dysplasia, achondrogenesis
— Mesomelic – campomelic dysplasia
— Acromelic – asphyxiating thoracic dystrophy, chondroectodermal dysplasia, short rib polydactyly - Non-lethal skeletal dysplasias
— Rhizomelic – achondroplasia, chondrodysplasia punctata, diastrophic dysplasia, spondyloepiphyseal dysplasia
— Mesomelic –
— Acromelic – pyknodysostosis - Shortened body portion
— Short limbed, normal trunk
—- Rhizomelic – proximal limb segments shortened – achondroplasia
—- Mesomelic – middle limb segments shortened
—- Acromelic – distal limb segments shortened
— Short trunk, normal limbed – chondrodysplasia punctata, spondyloepiphyseal dysplasia
— Short trunk and short limbed (Proportionate) – diastrophic dysplasia, mucopolysaccharidoses - Overview
— Achondroplasia – short limbed, normal trunk
— Diastrophic dysplasia – short limbed and short trunk
— Morquio syndrome (storage diseases) – short trunk
— Spondyloepiphyseal dysplasia – short trunk
— Chondrodysplasia punctata – short limbed