Estimation of the posterior tibial slope on magnetic resonance images in Serbian population

Background/Aim. Preservation of an adequate posterior tibial slope (PTS) during total knee arthroplasty is crucial for the biomechanical stability and function of the knee joint. Studies that investigated anatomical features of the tibial plateau found significant gender and inter-population differences in all components of the PTS. The aim of this study was to establish reference values of PTS in Serbian population and to explore if there is any difference in the tibial plateau inclination between genders. Methods. We retrospectively reviewed 161 magnetic resonance images (MRIs) of the knee of adult patients examined in Medical Military Academy in Belgrade, Serbia, in a period from November 2011 to September 2014. Measurements of PTS components: medial tibial slope (MTS), lateral tibial slope (LTS), and coronal tibial slope (CTS) were performed through several steps, according to the suggestions in the recent literature. Obtained values for each tibial slope were compared between gender subgroups using appropriate statistical tests. Results. Mean values of each component of the posterior tibial slope for male vs. female subgroups were as follows: MTS 3.7° ± 2.8° vs. 5.1° ± 2.9°, LTS 4.2° ± 2.8° vs. 4.3° ± 2.7°, and CTS 3.9° ± 2.4° vs. 3.3° ± 1.9° respectively. The medial tibial slope was significantly higher in females than in males (p = 0.005). The mean value of the coronal tibial slope was greater in males without statistically significant difference (p = 0.105). Conclusion. This study demonstrated significant difference in MTS of the tibial plateau between males and females, being higher in the female subgroup.