Rare group of genetic disorders mainly affecting bone; also known as brittle bone disease

Aetiology

• Defect of the maturation and organization of type 1 collagen (which accounts for most of the organic composition of bone)
• The majority of cases are autosomal dominant, rarer cases are autosomal recessive

Clinical features

• At least 8 types, of varying severity

Autosomal dominant

• Multiple fragility fractures of childhood
  • Can be mistaken for child abuse/non-accidental injury
  • Can be mistaken for osteopenia - can result from prematurity
• Short stature with multiple deformities
• Blue sclerae
• Dentinogenesis imperfecta
• Loss of hearing

Autosomal recessive

• Either fatal in the perinatal period or associated with spinal deformity

Investigations

• X-ray:
  • Bones tend to be thin (gracile) with thin cortices and osteopenic
  • Mild cases may have relatively normal x-rays with history of low energy fractures

Management

• No cure - only fracture fixation, surgery to correct deformities, bisphosphonates may have benefit in teenage years
• Fractures tend to heal with abundant but poor quality callus and are treated with splintage, traction or surgical stabilisation