Analysis of Synovial Fluid Metabolic Profile in Patients with Knee Osteoarthritis Using Spectroscopic Magnetic Resonance Metabolomics.

 The present study aimed to evaluate the metabolic profile of synovial fluid in patients with knee osteoarthritis (KOA) and its correlation with clinical data.  We collected synovial fluid samples from the knees of 50 subjects with KOA undergoing total knee arthroplasty from October 2019 to December 2020. For each patient, we evaluated the clinical data from the medical record, the radiographic osteoarthritis grade, and the preoperative fasting blood glucose levels. The samples underwent metabolomic analysis by 1H magnetic resonance spectroscopy, and we compared the spectra using multivariate and univariate analyses.  Most patients were female (66%). The subjects had an average age of 67.96 ± 7.08 years old and an average body mass index (BMI) of 32.51 ± 5.25 kg/m . Clinical and metabolic evaluations revealed that 88% of patients were hypertensive and presented higher levels of valine, arginine, and citrate than non-hypertensive subjects. Metabolomic analysis of synovial fluid cannot classify osteoarthritis patients per their clinical characteristics.