Background and purpose: Several randomized trials have demonstrated the lack of effect of arthroscopic lavage as treatment for knee osteoarthritis (OA). These results have in turn resulted in a change in Swedish guidelines and reimbursement. We aimed to investigate the use of knee arthroscopies in Sweden between 2002 and 2016. Patient demographics, regional differences, and the magnitude of patients with knee OA undergoing knee arthroscopy were also analyzed.Patients and methods: Trends in knee arthroscopy were investigated using the Swedish Hospital Discharge Register (SHDR) to conduct a nationwide register-based study including all adults (>18 years of age) undergoing any knee arthroscopy between 2002 and 2016.Results: The total number of knee arthroscopies performed during the studied period was 241,055. The annual surgery rate declined in all age groups, for males and females as well as patients with knee OA. The incidence dropped from 247 to 155 per 105 inhabitants. Over 50% of arthroscopies were performed in metropolitan regions.Conclusion: We showed a dramatic decline in knee arthroscopy. There is variability in the surgery rate between males and females and among the regions of Sweden.