A rare case report of fibrous dysplasia with aneurysmal bone cyst-like changes of femur and innominate bone

Abstract

Fibrous dysplasia (FD) is a common disorder of the skeletal system in which normal bone deposition and remodelling are disturbed and are replaced by anomalous fibrous tissue of varying stages. The age of presentation may vary depending on the genetic penetration and severity of the disease. Aneurysmal bone cyst (ABC) is a non-aggressive neoplastic pathology wherein there is the presence of blood-filled intramedullary cystic lesions and resultant aneurysm-like dilatation of the involved bone that may be a standalone true neoplasm or ABC-like changes associated with other lesions. Concurrence of FD with ABC-like changes is an uncommon entity with most of such cases involving the craniofacial location. To the best of our knowledge, only two cases of appendicular skeleton FD with ABC could be found in the literature, and neither of them is from the Indian subcontinent. Herein, we report one such case of appendicular FD with concomitant ABC-like changes presenting in the adolescent age group. Prompt and accurate diagnosis guides further surgical management and helps in avoiding inadvertent complications.