The objective of the study was to assess scintigraphic patterns and femoral shortening after femoral neck fracture in order to select predictive parameters for late complications. Eighty-eight patients with osteosynthesized femoral neck fractures were followed for 2 years with regular scintigraphic evaluations and orthoradiographic measurements of femoral length shortening. Four different patient categories were identified with regard to the late outcome two different groups with uneventful healing and two different groups with late complications. Accordingly, a high scintigraphic uptake at 1 month may either point to an uneventful healing if combined with minor femoral shortening or indicate failure if combined with a high degree of femoral shortening. In contrast, low scintigraphic uptake may either reflect primary fracture healing if accompanied by minor femoral shortening or predict failure if a high degree of femoral shortening is present. Compared with using scintigraphy alone, combined scintigraphic evaluation and assessment of femoral shortening increased the accuracy for prediction of late failures from 80% to 93%. Early scintigraphic patterns after osteosynthesis of femoral neck fractures have to be validated with care. Radiographic assessment of femoral shortening, which is less invasive, gives better prognostic accuracy and should therefore be preferred for this purpose.