Effectiveness of prior intra-articular corticosteroid injection in elderly patients with knee osteoarthritis undergoing progressive resistance training: a randomized controlled trial.

Objective: To evaluate the effectiveness of intra-articular injections (IAIs) with triamcinolone hexacetonide (TH) combined with a progressive resistance exercise program (PREP) in improving pain, function, muscle strength, and quality of life in elderly patients with knee osteoarthritis (OA).

Methods: Fifty-nine elderly individuals with knee OA were randomized into three groups: IAI with TH (IAI-TH) + PREP, IAI with saline solution (IAI-SS) + PREP, and IAI with placebo + PREP. The IAIs were administered once, one week before starting PREP, which was performed twice weekly for 12 weeks. Outcomes assessed at baseline and at 2, 6, and 12 weeks post-IAI included pain (Numerical Pain Scale - NPS), swelling, function (Western Ontario and McMaster Universities Osteoarthritis Index - WOMAC), quality of life (Short Form-36 - SF-36), performance tests (Six-Minute Walk Test - 6MWT, Timed Up and Go Test - TUGT, Short Physical Performance Battery - SPPB), and muscle strength (one-repetition maximum test - 1RM). Due to the COVID-19 pandemic, only 15 participants per group completed the study protocol.

Results: All groups showed significant intragroup improvements over time in pain, function, muscle strength, and quality of life. However, no statistically significant differences were found between the groups for any of the assessed outcomes. The bodily pain domain of the SF-36 and analgesic consumption were the only measures showing differences over time.

Conclusion: The combination of IAI-TH and a 12-week PREP (twice weekly) was not superior to IAI-SS or placebo combined with the same PREP in improving pain, function, or quality of life in elderly patients with knee OA. These findings highlight the role of exercise as a key therapeutic strategy, regardless of prior IAI. Future studies with larger sample sizes and long-term follow-ups are needed to better assess the role of intra-articular corticosteroid injections in OA rehabilitation.

Clinical trial number: ensaiosclinicos.gov.br (RBR-556md5g). Registered 27 October 2022.