Current Evidence on and Clinical Implications of Vitamin D Levels in Pain and Functional Management of Knee Osteoarthritis: A Systematic Review

Background: Osteoarthritis is a common chronic disease that affects quality of life and increases public health costs. Knee osteoarthritis is a frequent form, marked by joint degeneration, pain, stiffness, and functional restrictions. Factors such as age, genetics, joint injuries, obesity, and vitamin D deficiency can affect knee osteoarthritis progression. While the exact link between vitamin D and osteoarthritis is still being studied, recent research indicates that low vitamin D levels might influence the articular cartilage’s structure and function, potentially accelerating osteoarthritis. This review aims to analyze the last decade of research on vitamin D’s role in osteoarthritis. Methods: A systematic review of the literature was conducted in accordance with the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). Relevant studies from the last ten years were included to evaluate the association between vitamin D levels and knee osteoarthritis. The inclusion criteria were studies examining the role of vitamin D in cartilage health and osteoarthritis progression and the potential clinical implications for disease management. Results: This review identified a variety of studies exploring the connection between vitamin D and osteoarthritis, with mixed findings. Conclusions: The relationship between vitamin D and knee osteoarthritis remains inconclusive, highlighting the need for further research. An updated evaluation of the literature is crucial for osteoarthritis management strategies and to potentially include vitamin D supplementation in therapeutic protocols.