The Potential Role of Zilretta in Reducing Intra-Articular Effusions.

Background: Osteoarthritis pain results from articular cartilage degeneration that leads to the breakdown and ulceration of the joint surface accompanied by hypertrophic bone changes with osteophyte formation. Steroids are commonly used to treat osteoarthritis pain. Case Report: An 81-year-old female with a medical history of bilateral knee osteoarthritis presented to the outpatient physical medicine and rehabilitation clinic for management of chronic bilateral knee pain and effusion. The patient had historically been managed with short-acting steroids, viscosupplementation, and deep genicular radiofrequency ablation. After changing providers, the patient underwent a series of image-guided intra-articular injections with the steroids Kenalog (triamcinolone) and Zilretta (triamcinolone acetonide extended-release injectable suspension) and was also treated with Monovisc (hyaluronic acid viscosupplementation). In addition, the patient underwent cryoneurolysis treatment (iovera° [Pacira BioSciences, Inc]). Injections were administered bilaterally when indicated, while cryoneurolysis was limited to the left knee. A substantial reduction in aspirated effusion volume was observed following Zilretta injections, with 92.6% and 88.1% reductions in aspirate volume in the patient's left and right knees, respectively. Conclusion: Steroids have anti-inflammatory properties that reduce pain and improve function in patients with osteoarthritis, but steroid use for chronic effusion management also needs to be considered. Given our patient's knee effusion reduction after Zilretta injection, research is needed to confirm the ability of Zilretta to effectively reduce chronic effusion.