Figure 5. Alterations in synovial fluid metabolism post-injury are associated with different injury types.

Metabolites that differ in abundance across ligament, meniscal, and ligament and meniscal injuries are associated with amino acid, lipid, and linoleate metabolism, respectively. Multiple amino acids, bolded, were detected in synovial fluid from participants with ligament injuries. Metabolites detected among meniscal injuries were related to lipid metabolism, specifically the carnitine shuttle and beta-oxidation (orange). Combined ligament and meniscal injuries were associated with linoleate metabolism, which is related to arachidonic acid metabolism and the generation of prostaglandins and eicosanoids (yellow).