Fibrous dysplasia of bone is a skeletal disease due to a specific mutation in the GNAS1 gene with a broad spectrum of clinical presentations ranging from isolated monostotic and polyostotic forms to associations with other extra-skeletal manifestations (McCune-Albright syndrome). The main complications are bone pain, deformities and fractures and sometimes cranial nerve compression and the development of bone sarcomas. Traumatologic surgery represents the principal approach in complicated lesions. Currently, the efficacy of pharmacological therapies is fairly limited. Cyclic administration of intravenous biphosphonates is the most effective approach to achieve symptomatic improvement and to lower the risk of fractures, although more evidence from well-designed randomized clinical trials evaluating the safety and efficacy of these treatments is still required. We present a case of polyostotic fibrous dysplasia of bone in a 19-year-old male.