Radiology Cases Simple Bone Cysts LSBU

Description: The simple bone cyst is a benign unilocular lytic area in the proximal end of a long bone with a well defined and narrow endosteal margin. There is some expansion of the bone and thinning of cortex from below. This can occasionally give rise to a scalloped appearance appearance to some part of the cortex. The cyst is of low vascularity on isotope bone scanning with uptake only in the rim, unless a fracture has occurred. Fractures are often a presenting symptom. The thin rim of bone-cortex may fragment and pieces may fall through the semi-fluid contents of the cyst. This would be a diagnostic feature to distinguish simple cysts from solid tumours with a similar appearance.