Photo Credit: ChrisChrisW

The following is a summary of “Gut Microbiomics of Sustained Knee Pain in Patients With Knee Osteoarthritis,” published in the September 2024 issue of Rheumatology by Huang et al. 

Researchers conducted a prospective study to examine the association between gut microbes and sustained post-surgery knee pain in patients with knee osteoarthritis (OA). 

They recruited patients undergoing total knee replacement (TKR) for primary knee OA. Sustained knee pain, assessed at ≥1-year post-TKR, was defined using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Fasting plasma and fecal samples were collected for metabolomic profiling and microbial composition analysis via 16S rRNA sequencing. 

The results showed that among 20 patients with TKR, 10 had sustained post-surgery pain and 10 did not, matched by age, sex, and BMI (kg/m²). Analysis identified 13 bacterial taxa abundant in the pain group and 5 in the nonpain group (P < 0.05 for all). Plasma profiling of 622 metabolites found 18 taxa significantly correlated with 231 metabolites (P < 0.05 for all), with 30 metabolites explaining 29% of the variance between groups. Pathway analysis revealed significant enrichment in arachidonic acid metabolism, bile acid biosynthesis, and linoleic acid metabolism. 

The study concluded that gut microbes may significantly contribute to sustained knee pain in patients with knee OA after TKR, likely through inflammatory pathways, lipid metabolism, and central sensitization. 

Source: jrheum.org/content/early/2024/09/24/jrheum.2024-0361