The patient underwent surgery under general and caudal anesthesia. Lavage and biopsy of the cystic lesion were taken. The epiphyseal end of the cavity was bone grafted (from iliac bone) and the rest of the cavity was filled with bone cement.

Microscopic findings were: multiple fibro-osseous and fibro-collagenous tissue fragments showing bony trabeculae with interspersed bone marrow, variable-sized blood-filled spaces separated by fibrous septae with acute and chronic inflammation comprised of neutrophils, lymphocytes, plasma cells, histiocytes and multinucleated giant cells. No evidence of granuloma or malignancy is seen in the sections examined.

The radiological and histopathological features were compatible with aneurysmal bone cyst.

Acknowledgement:

• Thanks to Dr. Royeen Dehzad, Orthopedic surgeon for providing the surgery details.

• Thanks to Dr. Jamshid Jalal, consultant Histopathologist for providing the pathology details.