A study of T2 mapping of medial femoral condyle cartilage in healthy knee joints

CAO Nana; WANG Li; WAN Yeda; GUO Lin; HU Peng; HE Anwei

doi:10.19300/j.2024.L20974

Abstract：Objective To investigate the differences in T2 values of cartilage between each layer of the weight-bearing and non-weight-bearing areas of the medial femoral condyle in healthy knees measured by T2 mapping,and to explore the value of MRI quantitative study of articular cartilage by dividing it into different layers and areas.Methods A total of 22 healthy volunteers(11 males and 11 females,mean age of 27.05±1.05 years)were prospectively enrolled.The sample included 38 knee joints(20 in the left knee and 18 in the right knee).The volunteers underwent sagittal MRI T2 mapping examinations of knee joints,the thickest part of complete articular cartilage in both weight-bearing and non-weight-bearing areas of the medial femoral condyle were chosen and the T2 values were measured.A total of 35 weight-bearing areas were obtained,while 37 non-weight-bearing areas were obtained.Analysis of variance test was used to analyze the T2 values of the superficial,intermediate,and deep layers of articular cartilages in the same region.Independent sample t-test was used to analyze the T2 values of each articular cartilage layer between the weight-bearing and non-weight-bearing region of the medial femoral condyle.Results The T2 values of each cartilage layer in the weight-bearing and non-weight-bearing areas of the femur medial condyle exhibited a successive gradient from large to small,with superficial layer followed by intermediate layer and then deep layer.There was no significant difference in T2 values between the superficial and intermediate cartilage layers in the non-weight-bearing areas(P>0.05),while there were significant differences in T2 values between the other two layers(all P<0.05).The T2 values in intermediate and deep layers of the weight-bearing area were lower than those in the non-weight-bearing area(all P<0.05),while the T2 values of superficial layer between the weight-bearing area and the non-weight-bearing area were not significantly different(P>0.05).Conclusion The healthy knee cartilage can be divided into three layers based on the difference of T2 values,with the weight-bearing area exhibiting lower T2 values.Therefore,it is feasible to investigate knee cartilage through stratification and subregional analysis.