0521779407-16 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 21:18
1096 Osteogenesis ImperfectaOSTEOGENESIS IMPERFECTA
JAY R. SHAPIRO, MD
history & physical
History
■heritable disorder of connective tissue with mutations in type I col-
lagen in 90%: in 10% protein defect not identified
➣Usually dominant mutations, rare recessive or “mosaic” pattern
of inheritance
■multiple fractures: vertebral bodies, extremities
■first fractures at birth, may be delayed until first decade or later
■fracture incidence falls at puberty, increases in 50s
■positive family history in 65% of cases: new mutation in 35%Signs & Symptoms
■Patient appearance (phenotype) highly variable
■No defined relation of severity or phenotype to genotype
■Clinical classification: 4 major types have collagen mutations
➣Type I: Mild, little deformity, blue sclerae, dominant inheritance
➣Type II: Perinatal lethal shortly after birth, pulmonary insuffi-
ciency, severe skeletal deformities, “beaded” ribs from fractures,
“broad bone” extremities
➣Type III: Severe, progressive, fractures at birth, marked skeletal
fragility with deformities upper and lower extremities, scoliosis,
height 3 feet, wheelchair-bound, frequently white sclerae, scol-
iosis, “helmet” skull, blue or white sclerae, dentigenesis imper-
fecta
➣Type IV: Moderately severe skeletal fragility with long-bone
deformities, prominent scoliosis. Blue sclerae in childhood,
lighter scleral hue in adults. Usually use aids to ambulate because
of deformities.
➣Type V: Moderate to severe bone fragility, white sclerae, calcifica-
tion of forearm interosseous membrane, history of hyperplastic
callus after fractures, no collagen mutation
➣Type VI and VII (presumed) reported in single publications only,
no collagen mutation
■Diagnosis may be apparent at birth, especially if type II, III or IV:
multiple fractures, short limbs, pulmonary insufficiency, x-rays show
healing (prenatal) fractures of ribs and extremities
■Short stature, especially with more severe disease