Classification of intertrochanteric fractures with computed tomography: a study of intraobserver and interobserver variability and prognostic value.

The purpose of this prospective study was to determine the level of interobserver and intraobserver agreement among orthopedic surgeons and radiologists when computed tomography (CT) scans are used with plain radiographs to evaluate intertrochanteric fractures. In addition, the prognostic value of current classifications systems concerning quality of life was evaluated. Sixty-one patients who presented with intertrochanteric fractures received open reduction and internal fixation with compression hip screw. Three orthopedic surgeons and 2 radiologists independently classified the fractures according to 2 systems: Evans-Jensen and AO (Arbeitsgemeinschaft für Osteo-synthesefragen). Fractures were initially graded with plain radiographs and then again in conjunction with CT. Results were analyzed using the (kappa) kappa coefficient. The 36-item Short-Form Health Survey was administered at baseline, 3 months, and 1 year, and results were correlated with fracture grade. Mean kappa coefficients when comparing radiography alone with radiography and CT scan were 0.63 for the AO system and 0.59 for the Evans-Jensen system. Both represent "fair" agreements. Mean overall interobserver kappa coefficients were 0.67 for radiologists and 0.57 for orthopedic surgeons. Radiologists also had higher intraobserver kappa coefficients. No significant relationships were found between follow-up Short Form Health Survey results and intraoperative grading of fractures. When these classification schemes are compared, interobserver agreement does not appear to change dramatically when information from CT scans is added. This may suggest that (1) more data have been provided by CT with greater possibilities for misinterpretation and (2) these classification schemes may not be comprehensive in describing fracture pattern and displacement. Finally, both systems failed to provide any prognostic value.