Table 1 Sillence classification system for osteogenesis imperfecta
OI Type | Features |
|---|---|
Type I | Mildest form. Limited bone deformity and fragility. |
Type II | Lethal in perinatal period. |
Type III | Most severe form in patients who survive the newborn period. |
Type IV | Moderate severity. Spectrum of severity between types I and III. |
Additional OI types | Range in severity. Etiology is typically due to mutations in genes involved with collagen formation other than COL1A1 or COL1A2. |