Osteosarcoma knee LSBU

Description: Radiology case 454-3221 19 year old male with pain in the knee.
There is a lytic area which lies on the medial side of the proximal metaphysis of the right tibia. The lesion is not well demarcated over its whole boundary. The endosteal margin has a wide zone of transition between normal and abnormal bone. There is destruction of the overlying cortical bone, but the area is covered by the density of a lamellar periosteal reaction, which also extends over the diaphysis on its medial side. There is a general increase in density over the proximal metaphysis, which could be related to infiltrative sclerosis or a soft tissue extension outside the bone, another indication of a malignant bone tumour. The slight reduction in density of the medulla extending down the medial side of the diaphysis may indicate endosteal spread of the pathology, which is often under-read in plain film views.