Improved Pain and Function With Triamcinolone Acetonide Extended-Release and Cryoneurolysis for Knee Osteoarthritis: Use of a New Real-World Registry

Abstract

Background: Knee osteoarthritis (OA) affects 19% of American adults aged more than 45 years and costs $27+ billion annually. A wide range of nonoperative treatment options are available. This study compared 6 treatments: cryoneurolysis with deep genicular nerve block (Cryo-Deep/Both), cryoneurolysis with superficial nerve block (Cryo-Superficial), intra-articular hyaluronic acid (IA-HA) injections, nonsteroidal anti-inflammatory drug injections (IA-NSAIDs), IA-corticosteroids (IA-CS) injections, or IA-triamcinolone extended release (IA-TA-ER) injections over 4 months for: (1) pain severity and analgesic use; and (2) physical function (from Knee Injury and Osteoarthritis Outcome Score for Joint Replacement).

Methods: Patients who had unilateral knee OA and received nonoperative intervention were enrolled in the Innovations in Genicular Outcomes Research registry, a novel, multicenter real-world registry, between September 2021 and February 2024. A total of 480 patients were enrolled. Both pain and functional outcomes were assessed at baseline, weekly, and monthly, which were analyzed by overall trend, magnitude changes pretreatment to post-treatment, and distribution-based minimally clinically important difference (MCID) score. Multivariate linear regressions with adjustments for 7 confounding factors were used to compare follow-up outcomes among 6 treatment groups.

Results: Use of IA-TA-ER injections was associated with the lowest pain, greatest pain reduction, and highest prevalence of patients achieving MCID relative to other treatments (P < .001). Deep/Both-Cryo and IA-CS were associated with a higher prevalence of achieving MCID than IA-HA, IA-NSAIDs, and Cryo-Superficial (P ≤ .001). Use of IA-TA-ER was also associated with the greatest functional score, improvement from baseline, and highest prevalence of patients achieving MCID than other treatments (P ≤ .003).

Conclusions: The IA-TA-ER appears to outperform other treatments in terms of pain relief and functional improvement for up to 4 months following treatment. In addition, outcomes in the novel cryoneurolysis and conventional IA-CS were similar to one another and better than those in IA-HA and IA-NSAIDs.

Keywords: intra-articular injections; joint pain; knee osteoarthritis; nonoperative management; patient-reported outcomes.