A 13 year old boy, known to have hemophilia, came with a swelling over the left cervical region since two weeks. The swelling was hard, non-tender and with no skin erythema or local rise of temperature.
The contrast enhanced CT scan of the neck shows a well-defined, multiloculated, expansile lytic lesion with thin internal septae arising from the medullary cavity of the posterior aspect of the left first rib. There is post-contrast enhancement.