The Microbiome of Osteoarthritic Hip and Knee Joints: A Multicenter Investigation

Paired synovial fluid, tissue, and swab specimens were obtained and shipped to a centralized laboratory for testing. Following DNA extraction, microbial 16S rRNA sequencing was performed. Comparisons of paired specimens indicated that each is a comparable measure for microbiological sampling of the joint. Swab specimens were modestly different in composition and bacterial identification from synovial fluid and tissue. The five most abundant genera were Escherichia, Cutibacterium, Acinetobacter, Staphylococcus, and Pseudomonas. Although sample size varied, the hospital of origin explained a significant portion of variance (18.5%) in joint microbial composition, and corticosteroid injection within 6 months before arthroplasty was associated to elevated abundance of several lineages.