Study on the correlation between old ACL injury with medial meniscal tears and posterior slope of tibial plateau / 中华骨科杂志

ABSTRACT

Objective To explore the correlation between old anterior cruciate ligament (ACL) injury with medial menis-cal tears and posterior slope of tibial plateau. Methods Between July 2014 and February 2016, retrospective analyzed 177 pa-tients diagnosed with old ACL injury (injured to surgery time>3 months) who has been underwent arthroscopic treatment. 93 pa-tients included in this study contained 65 male and 28 female,the average age was (32.36±4.50) years old (ranged from 21 to 44 years). All patients were diagnosed with ACL rupture and no associated medial meniscus tear by MR examination at the time of in-jury and before operation. Posterior slope angle of tibial plateau was measured via MR. The patients were divided into two groups according to the presence of medial meniscus tear by preoperative MR examination. Statistical analysis was employed to analyze the difference between the two groups of patients's age, body mass index (BMI), posterior slope angle of tibial plateau, gender and side. The patients were divided into group of posterior slope of tibial plateau ≥10° and posterior slope of tibial plateau<10° re-spectively. Statistical analysis was employed to analyze the incidence of concomitant medial meniscus tear between the two groups. Result All 93 patients in this study were followed up for the average of 8.63 ± 3.74 months. 51(51/93, 55%) patients were com-firmed of concomitant medial meniscus tear and 42 (42/93, 45%) patients without medial meniscus tear through MR and arthro-scope. There was no statistical difference between two groups in age (t=0.843, P=0.843), gender (χ2=1.027, P=0.338), BMI (t=0.568, P=0.571) and side (χ2=0.110, P=0.438). There was a certain correlation between the medial meniscal tears and posterior slope angle of tibial plateau in this group and the values were considered statistically significant ( r=0.602, P=0.000). Posterior slope angle of tibial plateau of medial meniscus tear group (10.51°±2.83°) was significantly higher than that in non medial menis-cus tear group (7.39°±4.62°). Values were considered statistically significant .71.15%(37/51) of the patients showed medial meniscus tear in the group of posterior slope of tibial plateau ≥10° , however, only 34.14%(14/42) patients indicated medial meniscus tear in group of posterior slope of tibial plateau<10°, and the difference was statistically significant(χ2=12.677,P=0.000). Con-clusion There is a certain correlation between old ACL injury with medial meniscal tears and posterior slope angle of tibial pla-teau. With the continuous increase of ACL injury time, high posterior slope angle of tibial plateau (≥10°) is more likely to increase the incidence of medial meniscus tear.