Analysis of the correlation between media meniscus displacement index and medial tibiofemoral articular cartilage damage

Abstract

To investigate the correlation between the medial meniscal indentation index (MDI) and medial tibiofemoral articular cartilage damage more than 3 degrees in patients aged 40 to 60 years old with suspected or complicated knee osteoarthritis at non-weight-bearing position, and to determine the predictive threshold. From June 2016 to June 2020, a total of 308 patients who underwent initial knee arthroscopic exploration for chronic knee pain were collected. The age ranged from 36 to 71 years old with an average of(56.40±1.82) years old, including 105 males and 203 females. And patients with extra-articular malformations (abnormal force lines), a history of trauma, inflammatory arthritis and other specific arthritis were excluded. Finally, 89 eligible cases were obtained, aged from 42 to 60 years old with an average of (59.50±0.71) years old, including 45 males and 44 females. The degree of cartilage damage in the medial compartment of the knee joint was recorded, which was divided into two groups(≥degree 3 and<degree 3) according to Outer-Bridge classification system. The possible risk factors were determined by univariate analysis in the age, gender, affected sides, body mass index (BMI), synovial thickening grade, meniscus injury and MDI of 2 groups. Then, the independent risk factors for cartilage injury of more than grade 3 were determined by further binary Logistic regression analysis. If MDI was taken as an independent risk factor, receiver operating characteristic (ROC) analysis was performed to confirm whether it had diagnostic value for cartilage damage of above degree 3 and calculate the critical value of MDI. A total of 89 eligible patients were obtained. Univariate analysis showed age, BMI, MDI and meniscus injury may be the independent risk factors for cartilage damage of more than 3 degrees, further binary Logistic regression analysis confirmed that MDI[OR=1.66, 95%CI(1.64, 1.69), P=0.01]and BMI [OR=1.58, 95%CI(1.17, 2.15), P=0.03] were independent risk factors for cartilage injury of more than degree 3 in enrolled patients. ROC analysis showed that MDI had more diagnostic value than BMI, and the critical value was 0.355 with a sensitivity of 89.1% and a specificity of 88.2%. In doubt or accompanied by 40 to 60 years old patients with knee osteoarthritis, the MDI measured by non-weight-bearing knee MRI has predictive value for cartilage injury of more than degree 3 in medial tibiofemoral joint, and the critical value for diagnosis of cartilage injury of more than degree 3 is 0.355.