Skeletal Dysplasias

Question 1

what is skeletal dysplasia?

Answer 1

medical term for short stature (dwarfism is no longer used)

Question 2

what causes skeletal dysplasia?

Answer 2

due to a genetic error resulting in abnormal development of bone and connective tissue
- can be hereditary or sporadic

Question 3

is the short stature caused by skeletal dysplasia proportionate or disproportionate?

Answer 3

can be either
proportionate = limbs and spine proportionally short
disproportionate = limbs proportionally shorter or longer than spine

Question 4

what is the commonest form of skeletal dysplasia?

Answer 4

achondroplasia

Question 5

how is achondroplasia inherited?

Answer 5

80% are sporadic but some are autosomal dominant

Question 6

what does achondroplasia cause?

Answer 6

disproportionately short limbs with a prominent forehead and widened nose
joints are lax
normal mental development

Question 7

what are some symptoms of other skeletal dysplasias?

Answer 7

can be associated with:

• learning difficulties
• spine deformities
• internal organ dysfunction
• craniofacial abnormalities
• skin abnormalities
• tumour formation (haemangiomas)
• joint hypermobility
• atlanto-axial subluxation
• spinal cord compression (myelopathy)
• intrauterine or premature death

Question 8

how is skeletal dysplasia managed?

Answer 8

• genetic testing of child and family
• deformity correction (including scoliosis)
• limb lengthening
• growth hormone therapy