Which physical findings are characteristic of osteogenesis imperfecta (OI) type I?

Updated: Feb 24, 2020
  • Author: Manoj Ramachandran, MBBS, MRCS, FRCS; Chief Editor: Harris Gellman, MD  more...
  • Print

Type I OI is the mildest and most common form. Patients present with blue sclerae (often described as dark blue with a gray tinge), variable degrees of bone fragility, moderate bone deformity, and premature deafness. Height is usually normal. Exercise tolerance and muscle strength are significantly reduced, even with mild OI. Birth weight tends to be normal, though one or more bones may be fractured.

Fractures may occur for the first time at a later age (eg, when the child starts to walk). These fractures tend to heal well, though sometimes a hypertrophic callus response is seen. Fractures tend to decrease in frequency after puberty, but their frequency may increase later in life when age- and sex-related osteoporosis is superimposed. Over a lifetime, numbers of fractures can range from one to 60 or more.

People with OI have a high tolerance for pain. Old fractures can be discovered in infants only after radiographs are obtained for other reasons other than an assessment of OI, and they can occur without any signs of pain.

Involvement of the axial skeleton, in the form of scoliosis and kyphosis, is seen in 20% of cases. Dentinogenesis imperfecta is characteristic of OI type IB.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!