Learning Curve of Internal Fixation for Nondisplaced Femoral Neck Fractures: A Cumulative Sum Analysis

Background: The purpose of this study was to determine whether there is a learning curve for internal fixation for nondisplaced femoral neck fractures using the cumulative sum (CUSUM) technique. We applied the CUSUM technique in monitoring performance of a single surgeon in internal fixation for nondisplaced femoral neck fractures. Methods: Fifty consecutive patients who underwent internal fixation for nondisplaced femoral neck fractures were evaluated retrospectively. Loss of fixation within 6 months postoperatively was considered as failure of treatment. Patients were stratified into the early experience group (cases 1 to 25) and the late experience group (cases 26 to 50). The CUSUM method was used to analyze the learning curve. Results: There was no failure of treatment during study period. The operation time became shorter with experience. Using the CUSUM analysis to plot the learning curve, there was no significant learning curve observed for multiple pinning for nondisplaced femoral neck fractures. Conclusions: The CUSUM analysis revealed there was no obvious learning curve to become proficient at internal fixation for nondisplaced femoral neck fractures, if technical principles were followed during the procedure.