Evaluating Plasma Biomarker Concentrations in TKA Patients with Different Injection Histories- Madigan Research Day 2026

M Feldman, J Dobrich, R Frenette, F Say, L Gillette, Z Colburn, J Dannenbaum, M Bedrin

Abstract accepted for poster presentation at Madigan Research Day 2026

Background: Intra-articular injections are frequently used in the management of joint conditions prior to total knee arthroplasty (TKA). However, their impact on systemic inflammatory and immunological biomarkers remains unclear. This study aimed to evaluate plasma cytokine and chemokine profiles in TKA patients with varying histories of joint injections.

Methods: Peripheral blood samples were collected from 41 TKA patients categorized into three groups based on injection history: no prior injection (None, n=10), injection within six months (<6 mo, n=14), and injection more than six months prior to surgery (>6 mo, n=17). Plasma was isolated and analyzed using the Bio-Plex Pro Human Immunotherapy Panel, which quantifies 20 cytokines and chemokines. Biomarkers with more than 10% missing or out-of-range (OOR) values were excluded. Statistical comparisons of demographic characteristics and biomarker concentrations were performed using ANOVA, Kruskal-Wallis tests, and two-way ANOVA controlling for sex. False discovery rate (FDR) adjustments were applied to account for multiple comparisons.

Results: Demographic analysis revealed significant differences in sex distribution across groups (Fisher's exact test, p=0.0017), while age, race, and ethnicity showed no significant differences. Of the 20 biomarkers analyzed, seven were excluded due to high percentages of missing or OOR values. Statistical analysis of the remaining biomarkers revealed no significant differences across groups after FDR adjustment. However, several biomarkers, including IL-2, IL-18, and MCP-1, approached significance across multiple tests.

Conclusion: This study provides insights into the potential effects of joint injection history on systemic inflammatory biomarker profiles in TKA patients. While no significant differences were observed, trends in specific biomarkers suggest avenues for further investigation into the immunological impact of intra-articular injections.