A Quantitative MRI Research For Changes Of Quadriceps Tendon And Patellar Ligament In Osteoarthritis Of Knee

Objective:To investigate any difference between the quadriceps tendon and patellar tendon of the knee osteoarthritis(KOA)by a quantitative MRI technique-T2mapping.Further understanding differences in the biochemical structure of the quadriceps tendon and patellar ligament of the knee,and to provide the image basis for the evaluation of the correlation between the degeneration of the quadriceps tendon and the patellar ligament.Subjects and Methods:MRI was used to perform scans of the knee joint in normal volunteers,in the participants with knee joint symptoms and in patients scheduled for total knee replacement surgery.Normal routine knee scans along with quantitative T2mapping sequences were scanned for all the subjects.The subjects were divided into three groups:Group A-Normal control group,Group B-Symptomatic knee group and Group C–patients scheduled for total knee replacement surgery.The Functool software in ADW4.6 workstation was used to perform pseudo color processing on the original T2 mapping image.Maximum area of the quadriceps tendon was displayed on the sagittal image,thus the latter was used for evaluation.The quadriceps tendon in the scanned field were divided into three subregions(PQT,MQT,DQT).In all three locations,an area of 50mm~2 was manually selected along with three continuous point each of 1mm~2 as region of interest(ROI),which were measured as T2 values.The maximum area of the patellar ligament was displayed on the sagittal image,and the patellar ligament in the scanned field were divided into three subregions(PPL,MPL,DPL).The specific measurement method was the same as the quadriceps tendon.SPSS 21.0 software was used to analyze the differences in the T2 values between all three groups by single factor variance analysis of the quadriceps tendon and patellar ligament,as well as the difference of the T2 values between the quadriceps tendon and the patellar ligament in the three groups.P<0.05 was considered statistically significant.Results:(1)Quadriceps tendon:(1)There was no significant difference in the T2value of quadriceps tendon in the Groups A,B and C(P>0.05),and there was no significant difference on pairwise comparison(P>0.05).(2)In group A,there was a significant difference in the T2 value between PQT and DQT,MQT and DQT(P<0.05),and there was no significant difference in PQT and MQT(P>0.05).In group B,there was a significant difference in the T2 value between PQT and DQT(P<0.05).There was no significant difference in T2 value between PQT and MQT,MQT and DQT(P>0.05).In group C,there was a significant difference in the T2value between PQT and DQT(P<0.05).There was no significant difference in T2value between PQT and MQT,MQT and DQT.(2)Patellar ligament:(1)There was a significant difference in the T2 value of patellar ligament in the Groups A,B and C(P<0.05),and there was a significant difference on pairwise comparison(P<0.05).(2)In group A,the T2 values of PQT,MQT and DQT were not statistically significant on pairwise comparison(P>0.05).In group B,the difference of T2 value of PQT,MQT and DQT was statistically significant on pairwise comparison(P<0.05).In group C,there was no significant difference in T2 value of PQT,MQT,DQT on pairwise comparison(P>0.05).Conclusions:There are differences in the internal structure of the quadriceps tendon.The proximal quadriceps tendon contains more collagen and water.The T2 values of the quadriceps tendon didn't change at KOA.KOA occurred with degeneration of patellar ligament.The degenerative process of the patellar ligament at KOA is inconsistency and simultaneity.