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  • Brittle bone disease

  • 756.51 Osteogenesis imperfecta

  • Q78.0 Osteogenesis imperfecta

  • 5B: Impaired Neuromotor Development


  • Autosomal dominant genetic disorder that affects type I collagen resulting in osteopenia and frequent fractures that may be apparent in a newborn infant

Essentials of Diagnosis

  • Four types
    • Type I: Mild (most common)
    • Type II: Perinatal lethal
    • Type III: Progressive deforming
    • Type IV: Deforming with normal scleras
  • Types I and IV do not have fractures while in utero
  • Type II characterized by fractures in utero
  • Type III characterized by fractures at birth or as infant

General Considerations

  • Disorder results from type I collagen impairment that affects skin, bone, connective tissue of organs (including GI tract), and vascular system
  • Type I: fewer fractures after puberty; short stature and hearing loss as adult; blue sclera
  • Type II: usually results in death during infancy due to respiratory problems
  • Type III: usually non-ambulatory as an adult due to progressive deformities from multiple fractures over time; sclera affected; short stature, scoliosis
  • Type IV: short stature as adult, fractures continue as adult, but remains ambulatory; scoliosis; hearing loss; sclera unaffected


  • 1 in 20,000 births2
  • Infants
  • Males and females affected equally2

Signs and Symptoms

  • Fracture(s) at various times throughout lifespan (dependent on type of OI)
  • Blue sclera
  • Deafness at early age
  • Genu varum (bow legged)
  • Scoliosis
  • Kyphosis
  • Muscle weakness
  • Joint laxity
  • Brittle teeth

Functional Implications

  • May cause short stature or joint deformities that can interfere with function
  • May cause developmental delay due to immobility or casting associated with fractures
  • Weakness may limit function

Possible Contributing Causes

  • Inherited disorder

Differential Diagnoses

  • Child abuse
  • Juvenile osteoporosis
  • Temporary brittle-bone syndrome
  • Hypophosphatasia
  • Menkes syndrome
  • Steroid-induced osteoporosis

Laboratory Tests

  • DNA analysis
  • Collagen testing


  • Prenatal ultrasound
  • X-rays

Diagnostic Procedures

  • Chorionic villus sampling (CVS)
  • Amniocentesis
  • Skin punch biopsy

  • Chorionic villus sampling (CVS) is a prenatal test identifying chromosome abnormalities and other inherited disorders


  • Pamidronate

Medical Procedures

  • Surgical correction of fractures, such as intramedullary rod
  • Surgical correction of scoliosis

  • To hospital for surgical repair of fractures as needed
  • To geneticist for testing (especially if interested in offspring)
  • To occupational therapist
  • To orthosist
  • To orthopedic surgeon
  • To audiologist

  • Gross motor delay
    • Unable to sit independently
    • Unable to creep on hands and knees
    • Unable to stand at furniture
  • Decreased strength
  • Decreased ROM
  • Dependent ...

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