Speakers - 2027

Title: Gene expression biomarkers in the peripheral blood for postoperative pain prediction prior to knee or hip arthroplasty

Abstract

Osteoarthritis (OA) is a major source of pain, disability, and socioeconomic expenditures worldwide. Chronic postoperative pain after joint replacement is observed in 10-40% of patients with OA. Therefore, identification of the causes that affect the outcome of arthroplasty would permit a more accurate selection of patients and provide them with more accurate anticipations.

Methods: We examined peripheral blood of 31 hip and 50 knee OA patients undergoing joint replacement surgery and 26 healthy volunteers. Patients were tested before and 6 months after surgery. Pain was assessed using VAS index and neuropathic pain questionnaires DN4 and PainDETECT. Functional activity was evaluated by WOMAC. Total RNA isolated from whole blood was used in expression studies for cathepsin S, interleukin (IL)-1β, tumor necrosis factor (TNF)α, and cyclooxygenase (COX)2 genes using quantitative real-time RT-PCR.

Results: After 6 months’ post-surgery pain complaints were obtained from 38.7% patients with hip OA and 34% patients with knee OA. Patients with knee and hip OA who developed POP demonstrated significantly higher cathepsin S gene expression compared with painless subjects prior to surgery. In addition, patients with knee OA who developed POP demonstrated significantly higher expression of IL-1β and TNFα compared with painless subjects while no significant differences in the expression of proinflammatory cytokines were observed in both subsets of patients with hip OA.

Conclusion: Cathepsin S gene expression measured in the peripheral blood prior to surgery might serve as a prognostic biomarker of postoperative pain development in patients with knee and hip OA. Differences in prognostic value of IL-1β and TNFα gene expression measured in the peripheral blood prior to surgery might indicate that destruction of the hip and knee in OA is caused by different pathophysiological mechanisms.