Low interobserver reliability of radiographic signs predicting healing disturbance in displaced intracapsular fracture of the femoral neck

We determined the interobserver agreement of 3 radiographic signs previously shown to predict a disturbance in healing of femoral neck fractures. 6 orthopedic surgeons evaluated 32 radiographs for the presence of comminution of the femoral calcar, varus displacement in excess of 30 degrees and a small head fragment. They also classified the radiographs with Garden's method and determined the presence or absence of displacement. The kappa values were 0.2 for comminution of the calcar, 0.5 for varus displacement and 0.4 for a small head fragment. In the Garden classification, the kappa value was 0.4, increasing to 0.6 when divided into Garden 1-2 and 3-4. When the fracture was classified as displaced or undisplaced, the kappa value was 0.5. The strength of agreement of signs predicting a disturbance in healing was thus shown to be poor to moderate.