LAUSR

OBJECTIVES Describe associations between MRI markers with knee symptoms in young adults. METHODS Knee symptoms assessed using WOMAC scale during Childhood Determinants of Adult Health (CDAH)-knee study (year : 2008-10) and 6-9 year follow-up (CDAH-3; year : 2014-2019). Knee MRI scans, obtained at baseline, assessed for morphological markers (cartilage volume, cartilage thickness, subchondral bone area) and structural abnormalities (cartilage defects and bone marrow lesions (BMLs)). Univariable and multivariable (age, sex, BMI adjusted) zero-inflated Poisson (ZIP) regression models were used for analysis. RESULT Participants' mean age±SD in CDAH-knee and CDAH-3 were 34.95 ± 2.72 and 43.27 ± 3.28 years, with 49% and 48% females, respectively. Cross-sectionally, there was a weak but significant negative association between medial femorotibial compartment (MFTC) [ratio of mean (RoM)=0.99971084; 95%CI : 0.9995525-0.99986921; p< 0.001], lateral femorotibial compartment (LFTC) [RoM = 0.99982602; 95%CI : 0.99969915-0.9999529; p= 0.007], and patellar cartilage volume [RoM = 0.99981722; 95%CI : 0.99965326-0.9999811; p= 0.029] with knee symptoms. Similarly, there was a negative association between patellar cartilage volume (RoM = 0.99975523; 95%CI : 0.99961427-0.99989621; p= 0.014), MFTC cartilage thickness (RoM = 0.72090775; 95%CI : 0.59481806-0.87372596; p= 0.001) and knee symptoms assessed after 6-9 years. The total bone area was negatively associated with knee symptoms at baseline [RoM = 0.9210485; 95%CI : 0.8939677-0.9489496; p< 0.001] and 6-9 years (RoM = 0.9588811; 95%CI : 0.9313379-0.9872388; p= 0.005). The cartilage defects and BMLs were associated with higher knee symptoms at baseline and 6-9 years. CONCLUSION BMLs and cartilage defects were positively associated with knee symptoms, whereas cartilage volume and thickness at MFTC and total bone area were weakly and negatively associated with knee symptoms. These results suggest that the quantitative and semi-quantitative MRI markers can be explored as a marker of clinical progression of OA in young adults.