Recurrent intrapelvic cyst complicating metal-on-metal cemented total hip arthroplasty

Spontaneous intrapelvic masses causing vascular compression raise the suspicion of a neoplasm or infection. We present a patient who developed a recurrent intrapelvic cyst 14 years after a McKee-Farrar total hip arthroplasty which presented as acute onset of lower limb swelling, threatening the vascularity of the limb. This cyst recurred three times, and the patient finally needed revision total hip arthroplasty. The most probable cause of the recurrence was the cement and metal wear debris. Such cysts have been described in the literature, but to the best of our knowledge, this is the only report that describes it complicating a metal-on-metal prosthesis.