Simple bone cyst LSBU

Description: Radiology case 443-3181 4 year old boy, complaining of pain in the left hip.
There is a lobulated lytic lesion that expands the upper metaphysis of the left femur. The lesion is crossed by strands of dense bone that give it a multiloculate appearance. The endosteal margin of the lesion is well-defined with a narrow transition between normal and abnormal bone. The cortex is thinned from below, but appears thickened below the greater trochanter. There is no indication of lamellar newbone to indicate a cortical reaction. There is no record of a previous fracture and some of the appearance may be related to the fact that this bone is weight bearing with eccentric lines of force.