Does central sensitization affect responses to genicular radiofrequency and intra-articular injection in elderly knee osteoarthritis patients?

Objectives: This study aimed to evaluate the effect of central sensitization level on treatment response in individuals older than 65 years who underwent genicular nerve radiofrequency and intra-articular injection treatments for knee osteoarthritis (OA).
Methods: In this retrospective cohort study, 37 patients were divided into two groups according to the Central Sensitization Inventory (CSI) score (CSI<40 and CSI≥40). All patients underwent genicular nerve radiofrequency ablation and intra-articular injection. Pain (NRS), functionality (WOMAC), walking capacity (6MWT), sleep quality (PSQI), and satisfaction levels were evaluated at baseline and at 1 and 3 months following the procedure. Variance and regression analyses were used for statistical evaluation.
Results: Significant clinical improvements were observed in all patient groups for the evaluated parameters (p<0.001). However, variance analysis for pain (F=22.566, p<0.001), function (F=15.283, p<0.001), sleep quality (t=–3.87, p<0.001), and walking capacity (F=13.301, p=0.001) showed lower scores in the CSI≥40 group compared with the CSI<40 group. Regression analysis confirmed lower responses in CSI≥40 patients: pain (β=–2.1; 95% CI: –3.1 to –1.1; p<0.001), function (β=–4.6; 95% CI: –7.2 to –2.0; p=0.001), walking (β=–24.6; 95% CI: –40.7 to –2.8; p=0.026), and sleep (β=–1.9; 95% CI: –2.9 to –0.9; p=0.001).
Conclusion: The presence of central sensitization significantly limits the clinical response to genicular radiofrequency ablation and intra-articular injection treatments in older patients with OA. Routine use of screening tools such as CSI in treatment planning may guide more effective and personalized approaches.

Keywords: Central nervous system sensitization, elderly, knee, osteoarthritis, radiofrequency ablation.