The Inflamma-type: a patient phenotype characterized by a dysregulated inflammatory response after lower extremity articular fracture.

Synovial fluid was collected from 113 patients who had suffered tibial plateau (n = 48), tibial plafond (n = 29), or rotational ankle fractures (n = 36). Concentrations of IL-1ß, IL-1RA, IL-6, IL-8, IL-10, and MMP-1, -3, and -13 were quantified using multiplex assays. A cluster analysis of synovial fluid biomarker concentrations was performed. Patient demographics, fracture type, Injury Severity Score (ISS), Charlson Comorbidity Index (CCI), and biomarker concentrations were compared between clusters. A subset of patients demonstrated a dysregulated inflammatory response after articular fracture including elevated pro-inflammatory cytokines and degradative enzymes previously linked to the development of post-traumatic osteoarthritis.