A 73-year-old female presented to her general practitioner with a complaint of difficulty with walking, and an inability to weight bear on her right side. She also complained of pelvic pain, and had noticed an abdominal mass centrally and on her right side. There was no history of vaginal bleeding, discharge or a change in bowel habits. The general practitioner suspected a possible gynaecological cause for her presentation, most likely fibroid uterus, and subsequently referred her to a gynaecologist for further work up. She also had a history of five previous hip replacement operations for severe osteoarthritis of her hip joints, three on her right and two on her left side. Her last surgery was for her 3rd right hip total arthroplasty. This last total hip replacement surgery was performed in a teaching hospital setting. There were postoperative complications, most significantly a cold right lower limb. For this she had undergone successful endovascular stenting of her right external iliac artery and was discharged home. Her current presentation was 6 months after the last surgery. Gynaecological examination revealed a firm non-tender right iliac fossa mass. Vaginal examination revealed mobile masses protruding into the pouch of Douglas. Ultrasound examination of the pelvis demonstrated extensive acoustic shadowing. A working diagnosis of possible retained swab with a granulomatous mass was entertained. Having now suspected a non-gynaecological aetiolgy for her presentation, plain film radiographs were requested. Supine pelvis and lateral hip radiographs (,) demonstrated superior migration of the femoral head component of the prosthesis into the right side of the pelvis as well as a dislocated acetabular component lying in the mid lower pelvis. On lateral view the dislocated acetabular component was situated in the region of the pouch of Douglas with its screws directed inferiorly. The patient was transferred to a teaching orthopaedic unit where she underwent emergency surgery for removal of the intrapelvic acetabular cup. It was postulated by the surgeons that her multiple revision surgeries and osteoporotic bone state predisposed her to protruso acetabuli prosthetica. Her surgery involved a laparotomy with a transperitoneal approach. In view of the extensive destruction of the acetabular bone salvage was done using a saddle prosthesis and a total femoral replacement. This was done at a different institute and thus a follow up radiograph was not available