Bone
Non-neoplastic or metabolic disease
Osteogenesis imperfecta

Author: Nat Pernick, M.D. (see Authors page)

Revised: 3 October 2016, last major update August 2013

Copyright: (c) 2003-2016, PathologyOutlines.com, Inc.

PubMed Search: Osteogenesis imperfecta
Cite this page: Osteogenesis imperfecta. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/boneosteogenesisimperfecta.html. Accessed December 7th, 2016.
Definition / General
  • Also called brittle bone disease
  • One of the most common congenital connective tissue matrix diseases
  • Disease of type I collagen due to mutations in genes coding for alpha 1 - 2 collagen chains, usually autosomal dominant
  • A type of osteoporosis with marked cortical thinning and attenuation of trabeculae, plus other collagen related signs / symptoms
  • Skeletal abnormalities may be mild (reduced amounts of normal collagen) or severe/lethal (abnormal polypeptide chains cannot form collagen triple helix); associated with short stature and increased fractures (hundreds of minor / major fractures during childhood, usually in lower limb, often involving growth plate fragmentation around knees)
  • Blue sclera: due to translucent sclera and visualization of choroid
  • Hearing loss: sensorineural defect and impeded conduction due to abnormalities of middle ear bones
  • Dental imperfections: small, misshapen, blue - yellow teeth, due to dentin deficiency
  • Type I: usually acquired mutation, autosomal dominant, normal lifespan with increased fractures during childhood but decreasing after puberty
  • Type II: usually autosomal recessive, uniformly fatal due to extraordinary bone fragility with multiple intrauterine fractures; unstable triple helix
  • Type III: autosomal dominant or recessive, growth retardation, but otherwise like type I
  • Type IV: autosomal dominant, short stature, but otherwise like type I
Radiology Description
  • Nodules of cartilage at growth plate resembling a bag of popcorn
  • Marked swelling of distal femur
Gross Description
  • Cartilaginous nodules due to fragmentation of growth plate
Micro Description
  • Severe forms lack an organized trabecular pattern
  • Crowded osteocytes within bone (due to reduced collagen synthesis)
  • Large areas of woven bone
  • Less severe forms still have crowded osteocytes with thin lamellar bone