Abstract
Introduction
Optimal alignment of the tibial component in TKA is an important consideration. General agreement exists on the appropriate coronal alignment. However there is no consensus on sagittal alignment (posterior slope). Some surgeons target a fixed posterior slope (usually between 0 and 10 degrees), while others attempt to match the patient's intrinsic anatomy. The purpose of this study was to evaluate the tibial posterior slope in patients undergoing TKA.
Methods
13,586 CT scans of patients undergoing patient specific were analyzed. Three-dimensional reconstructions were performed and the posterior tibial slope was measured. Mean slope and ranges were determined.
Results
Mean tibial posterior slope was 7.2 +/− 3.7 degrees (range −5 to 25 deg.) 35% of patients had tibial slope measurements more than 3 degrees different from the mean slope of this population.
Conclusion
This study demonstrated a remarkable variability of tibial slope in patients undergoing TKA. This information may be useful to surgeons in determining “optimum” sagittal alignment of the tibial component for an individual patient. A patient with preoperative tibial slope very different from “average” may be at risk for sagittal malalignment of the tibial component. Additionally, large preoperative to postoperative changes in tibial slope may adversely affect knee kinematics and clinical outcome.
