The Effect of Abnormal Tibial Slope on Medial Meniscus Tear

Objective: To study the relationship between tibial plateau retroversion and medial meniscus injury, and further discuss and explore the abnormal anatomical factors. Methods: 36 patients who underwent knee surgery in overseas Chinese hospital from 2011 to 2022 were randomly selected and divided into groups A and B. Group A (28 cases) had definite medial meniscus injury, while group B (8 cases) had no medial meniscus injury and underwent other operations. All medial meniscus injuries met the diagnostic criteria and could be observed under arthroscopy. The tibial plateau caster angle (PTS) was measured on MRI, and the statistical significance was determined by two independent sample t-test and chi square test. The variables with statistical significance were analyzed by binary logistic regression. Finally, the independent risk factors of medial meniscus injury were determined, and the 0r value was calculated. P value <0.05 was considered statistically significant. Results: there were 28 knees in group A and 8 knees in group B. There was no significant difference in age, sex and BMI between the two groups (p>0.05). The main tear sites of medial meniscus were posterior horn tear (57,14%) and body tear (14.28%), and the tear types were complex tear (32.1%) and horizontal tear (21.4%). The average PTS of group A (8.69 °) was significantly higher than that of group B (6.22 °) (p<0.01). The results of binary logistic regression analysis showed that PTS was statistically significant (p<0.005), so we believed that the increase of PTS (OR=1.62, 95%CI, 1.086～2.403) was an independent risk factor for medial meniscus injury. Conclusion: PTS is higher in patients with medial meniscus injury. The abnormal anatomical structure of increasing retroversion is a risk factor for medial meniscus injury.