- Most common noncancerous (benign) bone tumor, 40% percent of all benign bone tumors (9% of all bony tumors).
- Painless, solitary or mulitple, usually pediatric poulation, may grow in a child or adolescent.
- 1% has malignant degeneration of cartilage cap.
- Occurs when part of the growth plate forms an outgrowth on the surface of the bone. This bone outgrowth may or may not have a stalk (pedunculated or sessile).
- Around the knee is the most common location.
- Cartilage cap >1.5 cm raises concern for calignant transformation (chondrosarcoma).
Multiple hereditary exostosis aka (Osteochondromatosis) - AD disease, 3-5% malignant degeneration
Trevor's disease - osteochondroma of epiphysis