Extended-release triamcinolone provides prolonged relief for patients who failed standard corticosteroid injection for knee osteoarthritis; a pragmatic retrospective study.

Objective: Identify if extended-release triamcinolone has a longer duration of action in a cohort of patients who have had limited duration of relief from prior corticosteroid injection. Design: Retrospective analysis of patients with knee osteoarthritis. Setting: Academic outpatient musculoskeletal practice. Subjects: One hundred and fifty patients (age 67.5 ​± ​13.7, 68.2% female) with knee osteoarthritis who had subjectively insufficient relief from a standard corticosteroid injection. Methods: Ultrasound-guided knee injections of extended-release triamcinolone were administered to all patients by experienced practitioners. The primary outcome measure was comparative duration of subjective relief from extended-release triamcinolone, compared to the patients' duration from their prior standard corticosteroid injection. The secondary outcome was the duration of relief from extended-release triamcinolone. Results: Patients reported 7.1 ​± ​8.7 additional weeks of relief from extended-release triamcinolone (t ​= ​6.50, p ​< ​0.001), with lower Kellgren-Lawrence score being the only factor associated with increased comparative duration of relief (B ​= ​-2.39, p ​= ​0.042). No factors were associated with duration of pain relief from extended-release triamcinolone. Conclusions: This retrospective study suggests that injection of extended-release triamcinolone is associated with prolonged pain relief in patients who have had insufficient duration of pain relief from a standard corticosteroid injection. Those with lower Kellgren-Lawrence grades were more likely to have an increased comparative duration of relief.