A Narrative Review on Intra-Articular Injection Therapies for Knee Osteoarthritis: Current Evidence and Future Perspectives

Abstract: This narrative review summarises current evidence on intra-articular injection therapies for knee osteoarthritis. Knee osteoarthritis (OA) is a major global cause of disability, particularly among older adults, prompting growing interest in non-operative strategies that alleviate symptoms, preserve joint function, and delay surgical intervention. Established options including corticosteroids and hyaluronic acid, remain widely utilized for short and intermediate-term symptom relief. Regenerative approaches such as platelet-rich plasma (PRP) and mesenchymal stem cells (MSCs) have gained prominence due to their potential anti-inflammatory and reparative effects. Novel biologic agents, including exosomes, atelocollagen, and isolated growth factors, show promise in supporting tissue repair and modulating joint homeostasis. Given the wide variability in mechanisms, efficacy, and safety profiles, selection of treatment regimen should be individualized based on disease severity, patient goals, and regulatory considerations. Overall, intra-articular injection therapies represent a diverse and rapidly evolving component of knee OA management. Continued high-quality randomized trials and standardized treatment protocols are essential to support evidence-based clinical decision-making and optimize patient outcomes. Keywords: knee osteoarthritis, intra-articular injection, platelet-rich plasma, mesenchymal stem cells, exosomes, hyaluronic acid, prolotherapy