Osteoclastoma proximal tibia LSBU

Description: Radiology case 454-3182 2 cases
Painless swelling of the knee in a young woman. There is a lytic process in the tibia. Note that the expanding lesion extends to the joint and is in a mature skeleton. Its centre of radius is not in the middle of the bone, the involvement is asymmetrical. The endosteal margin anteriorly and inferiorly is well-defined with a narrow zone of transition, but posteriorly is ill-defined with a wider zone of transition from abnormal to normal bone.
40 year old woman with vague pain / discomfort in left knee. There is a lytic process in the tibia with slight expansion of the upper metaphysis, more on its lateral side. The medial end-plate of the tibia is depressed with some irregularity that resembles a past fracture depression. The density is non-homogeneous lower density with many strands of bone crossing it and giving a multiloculate appearance. The lesion is very well-defined with a narrow sclerotic endosteal margin. The cortex is thinned from below, but no lamellar cortical reaction is seen. There are incidental osteophytes at the articular margins of the patella.