7. Borders of lesion determine its growth rate. 1A, sharp sclerotic; 1B, sharp lytic; 1C, ill-defined

8. Patterns of bone destruction. A: it determine lesion's growth rate. B:geographic type :uniformly affected area within sharply defined borders, giant cell tumor. C: moth-eaten :rapidly growing infiltrating lesions, myeloma. D: permeative type :round cell tumors, Ewing sarcoma. Note: almost imperceptible destruction of metaphysis of femur by a tumor that has infiltrated medullary cavity and cortex and extended into surrounding soft tissues, forming a large mass.

9. Types of periosteal reaction. uninterrupted indicates a benign process, interrupted reaction indicates a malignant or aggressive nonmalignant process

10. Types of matrix chondroid calcifications. A: Schematic B:Enchondroma displays a typical chondroid matrix. C: Chondrosarcoma with characteristic chondroid matrix.

11. Soft tissue mass. Radiographic features of soft tissue extension characterizing malignant or aggressive bone lesions and benign processes

13. Radiographic features