Quantitative magnetic resonance imaging of knee cartilage for the assessment of post-traumatic cartilage injury

In a case of knee trauma, a meniscus tear is one of the most frequent findings in magnetic resonance imaging (MRI). Due to literature, such meniscus tears can be connected with a traumatic injury of articular cartilage of tibial and femoral condyle. Thanks to the image provided contrast, MRI is the first method of choice to evaluate injuries of knee soft tissue structures - meniscus, Līgaments, and articular cartilage. In this study for qualitative cartilage, evaluation authors used standard FSE PD fat saturation and T2 mapping sequence. The abstract aim is to evaluate the condition of articular cartilage in subjects with a post-traumatic injury of the knee. Study period from October 1 until December 29, 2020. Riga City 1. Hospital, Department of Radiology, General Electric DISCOVERY 750W 3.0 T MRI system. The study includes 53 patients. Two groups: patients without meniscus tear (n=22) and individuals with a meniscus tear (n=31). Inter-rater-agreement (Kappa). In control group for lateral condyle cartilage 0.78 (95% CI 0.55–1.00), for medial condyle cartilage 0.91 (95% CI 0.76–1.00). In meniscus tear group for lateral condyle cartilage 0.75 (95% CI 0.51–1.00), for medial condyle cartilage 0.97 (95% CI 0.92–1.00). Unpaired T test for T2 relaxation time: FLM,p=0.26, FLL,p=0.3, FMM,p=0.25,, FML,p=0.08, TLM,p=0.54, TLL,p=0.9, TMM,p=0.53, TML,p=0.54. Groupe analysis by location: FLM,n=7(33.3%)/n=13(41.9%), FLL,n=3(14.3%)/n=11(35.5%), FMM,n=4(19.0%)/n=14(45.2%), FML,n=2(9.5%)/n=9(29.0%), TLM,n=1(4.8%)/n=8(25.8%), TLL,n=2 (9.5%)/n=5 (16.1%), TMM,n=1(4.8%)/n=7(33.3%), TML,n=2(9.5%)/n=5(16.1%). Inter-rater-agreement (Kappa) showed good and very good strength of agreement. Early cartilage damage such as edema - high T2 relaxation time values (above 40 m/sec) was present in both groups - early cartilage damage is not necessarily related to tear off the meniscus.  Statistical analysis didn't show a significant difference in cartilage T2 relaxation time between selected groups. However, the prevalence of high T2 relaxation time showed clear differences between selected groups.