Failure of internal fixation of displaced femoral neck fractures in rheumatoid patients. We reviewed the records and radiographs from 10 hospitals to identify 50 patients with rheumatoid arthritis (RA) who had sustained 52 femoral neck fractures. Most patients were female (88%), elderly (mean age 66 years) and had had severe polyarticular disease for a mean duration of 16 years. Over half had taken systemic corticosteroids, nearly all were severely osteopenic but few had rheumatoid changes in the hip. Of the 20 fractures treated by internal fixation 12 had complications including nonunion (5), osteonecrosis (5), infection (1), and intertrochanteric fracture (1). Only one of the nine undisplaced fractures required reoperation, but seven of the 11 displaced fractures had revision surgery. Twenty fractures were treated by primary total hip arthroplasty with only one early complication. The other 12 fractures had been treated by hemiarthroplasty (9), hip excision (1) or non-operatively (2). Our results suggest that, in elderly rheumatoid patients, severely displaced femoral neck fractures should be treated by total hip replacement. 