Hip joint hydatidosis after prosthesis replacement.

Hydatidosis is a rare parasitic disease caused by the Echinococcus tapeworm, which only occasionally affects the musculoskeletal tissues. In this article we describe the case of a patient who underwent a total hip replacement procedure for a pathological fracture of the femur neck. At the next histological examination it was shown to be a consequence of secondary bone hydatidosis. This clinical case is exceptional in that the infection spread to the cotyloid and femoral prosthesis components and, in the following years, caused repeated episodes of joint dislocation.