Particulate wear debris osteolysis, acute urinary retention and delirium as late complications of hip arthroplasty.

Intrapelvic mass formation as a result of particulate wear debris induced osteolysis is a recognised late complication of cementless total hip arthroplasty. Clinical presentation typically involves hip and/or leg pain resulting in functional impairment, and obstructive urinary symptoms developing 3-20 years after surgery. An acute confusional state has never been described in this scenario. We report the case of an 86-year-old gentleman with a diagnosis of dementia brought to our emergency department with an acute confusional state. Abdominal imaging revealed a distended bladder, a large pelvic mass and a lytic lesion within his right acetabulum. Cytological and microbiological examination of fluid obtained with radiologically guided aspiration of the mass was negative for neoplasia and infection.