occurs mainly in the 5–20-year old age group, but is also seen in the elderly following malignant change in Paget’s Disease. (bi-modial disease; i.e. found in young age more commonly and old age)
The tumour often arises in a metaphysis, most commonly around the knee. There is usually bone destruction with new bone formation, and periosteal reaction is present( ‘sunray appearance’) +/- Codman triangles
Osteosarcoma of the distal femur
- X-ray right knee (AP and lateral views) of a patient with osteosarcoma
- An ill-defined cloud-like lesion with a wide zone of transition (green overlay) is seen in the distal femur. An aggressive type of periosteal reaction known as a Codman triangle (C) is visible medially. Additional aggressive periosteal reaction seen posteriorly has produced a sunburst pattern (S).