The study analyzed the global burden of osteoarthritis (OA) in adults aged 55 years and older based on data from the Global Burden of Disease 2021 study. In 2021, the incidence reached 7.94 million cases (ASIR 30,395.11 per 100,000), the prevalence 594.35 million cases (ASPR 30,395.11 per 100,000 000) and DALY 16.05 million (ASDR 1,075.70 per 100,000). Since 1990, all indicators have increased significantly, with the highest burden in regions with a high sociodemographic index (SDI). Women had higher rates than men, the rising incidence peaked at ages 55–59, and risks increased in more recent birth cohorts. Globally, 35.8% of DALYs attributed to OA were associated with high BMI (≥ 25 kg/m²), with high-income North America having the greatest burden. Forecasts predict an increase in ASIR by 9%, ASPR by 14% and ASDR by 12% by 2050. The study emphasizes the need to prevent risk factors such as high BMI.