types and radiological features of skeletal dysplasia by dr- passant abdul nasser

1. Skeletal Dysplasia

2. What the cause ?
• The condition is
caused by
defective genes
that either are
inherited from a
parent or mutate
randomly
during fetal
development.
Skeletal dysplasia is a
generalized structural
abnormality of bone
growth and modelling.
Bone modelling is a
consequence of osteoblast
and osteoclast activity and
growth / morphogenetic
factors are important in
development. The main
structural protein of bone
and cartilage is collagen.
Mutations in collagen
genes cause generalized
dysplasia.

3. When in doubt screen prenataly by
U/S
1 – look for frontal bossing
2- bone length
3 –leg foot relationship
4- axial shape of chest cage
5- rib thickness and curvature
6- foot clubbing or inversion

5. Skeletal dysplasia could be lethal !
So
How to classify !
What to look for to diagnose !

6. • The skeletal dysplasias are genetically heterogenous
and can be inherited as autosomal dominant,
• autosomal recessive,
• X-linked recessive,
• and X-linked dominant disorders,
• and rarer genetic mechanisms of disease including
chromosomal deletions/duplications,
• germline mosaicism,
• and uniparental disomy have been seen.

9. • Spondyloepiphyseal
- SED congenita
- SED tarda
• Spondylometaphyseal
- SMD kozlawski
• Craniometaphyseal
• craniodiaphyseal

10. Cleidocranial dysplasia.
Radiographs of skull (A, B)
show open fontanelles and
wormian bones (arrows, A)
and hot cross bone
appearance (arrow, B).
Radiograph of chest(C)
shows hypoplastic right
clavicle (arrow). Radiograph
of hand (D) shows
elongated second digit with
an accessory epiphyseal
centre (arrow) Radiograph
of pelvis (E) shows " chef-
hat " shaped femoral heads
(arrow) and widened pubis

13. • Achondrogenesis
• Thanatophoric dysplasia
• Asphyxiating thoracic
dysplasia
• Osteogenesis imperfecta
• Dysplasia epiphysialis
punctata

33. • Osteopetrosis
• Pyknodysostosis
• Osteopoikilosis
• Melorheostosis
• Osteopathis striata
• Sclerosteosis

70. MCHD

93. Shephered crook deformity

94. Poly ostotic fibdous dysplasia

98. Trevor fair-bank disease

99. Trevor fair-bank disease

103. Proximal femoral focal
defeciency (PFFD)