Interpreting preoperative radiographs in displaced femoral neck fractures:: observer variability in evaluating signs of poor outcome

Objective To evaluate the reproducibility of four preoperative radiographic signs thought to be associated with negative prognosis in dislocated femoral neck fractures when treated with internal fixation. Setting University Hospital. Design Standard hip radiographs of ten patients with displaced subcapital femoral neck fractures were studied by five orthopaedic surgeons. The radiographs were studied twice; the second time on average 3 months after the first reading. Inter- and intra-observer reliability of four radiological parameters was estimated. Results Poor intra- and inter-observer reproducibility of all four signs tested was observed. Conclusions The decision to treat an intracapsular femoral neck fracture with either prosthesis or internal fixation has to be based on other variables than the preoperative radiographic signs evaluated in this study.