Abstract
Objectives
The posterior tibial slope (PTS) has been widely studied because of its relationship with tibial translation, knee stability and possible injuries related to the anterior cruciate ligament. But there is no consensus on the normal and pathological values for PTS and the best referral axes.
Methods
In this study, 96 people with non-orthopedic disorder were evaluated trough 3-D computed tomography (CT) scan. The TS of the medial and lateral tibial plateaus were measured using techniques adapted from previous protocols with three referral axes: the proximal tibial long axis, the anterior and posterior cortices. The CT scan were evaluated with two independent observers.
Results
The averages and standard deviations of medial PTS (MPTS) in the three methods were 10.4 ± 2,8, 8,3 ± 2,8 and 5,9 ± 2,8, separately. The results of lateral PTS (LPTS) were 9,9 ± 3,3, 7,8 ± 3,1 and 5,7 ± 3,1. There was no significant difference between the male and the female. All the referral axes had high interobserver reliability, with greater value (0.829) for posterior cortice axe for medial TS and anterior cortice for lateral TS (0.861).
Conclusion
The mean value for posterior tibial slope in a small Brazilian sample is similar to other ethnicity described in the literature. Tibial slope measurements have a high degree of variability between different measurement methods, but all referral axes had a high interobserver reliability.