Background:Patients with knee osteoarthritis (OA) who do not achieve adequate pain relief and functional improvement with a combination of non-pharmacologic and pharmacologic therapies are recommended an arthroplasty as an effective option to relieve severe pain and functional limitations. However, some patients are reluctant to undergo surgical interventions, and clinicians may choose to avoid or delay surgery due to safety risks and/or the financial cost. It is of interest to understand if the use and perception of surgery differs between countries, however, few published data exist.Objectives:To demonstrate how surgery and the use of surgical procedures differs across Japan, United States of America (US) and 5 major European countries (EU5) and to evaluate patient perception towards surgery.Methods:Data were drawn from the Adelphi OA Disease Specific Programme (2017-18), a point-in-time survey of primary care physicians (PCP), rheumatologists (rheums), orthopaedic surgeons (orthos) and their OA patients. Patients with physician-diagnosed knee OA were included and segmented into two categories: had previous surgery (PS) and never had surgery (NS). A Fisher’s exact test was performed on the two groups. Physicians reported on patient demographics; whether patients had undergone surgery; type of surgery; success of surgery; how success was defined; and reasons for wanting to delay surgery. Patients reported their willingness to undergo surgery; reasons for not wanting surgery; how successful their surgery was; and how they defined this success.Results:Physician/patient reported data were available for 302,230 (Japan), 527,283 (US) and 1487,726 (EU5) patients with diagnosed knee OA. Patients were categorised by their physicians as mild (40% Japan; 34% US; 24% EU5), moderate (49% Japan; 49% US; 56% EU5) or severe (9% Japan; 17% US; 19% EU5). Patients in Japan were more likely to be female (78% vs 54% US; 58% EU5), older (73 vs 65 US; 66 EU5) and have a lower BMI than patients in the US and EU5. Obesity and diabetes were much less prevalent among patients in Japan. One in ten patients in Japan had undergone a surgery (10%), far fewer than in the US (22%) or EU5 (17%). When surgery was performed, this was more likely to be a total joint replacement (TJR) in Japan, whereas in the EU and US, arthroscopic washout was more commonly performed.For over half of Japanese patients (56%), successful surgery was more likely to be defined as having no more pain (vs. 35% US; 14% EU5). Improved mobility and a reduction in pain were also commonly reported reasons. Physicians (in each region) were more likely to suggest pain reduction, rather than no pain, and improved mobility as markers of success. Patients in Japan were much more likely to say they would not agree to surgery if recommended by their doctor, or were unsure (84% vs. 68% US; 62% EU5). The main reason for patient reluctance in Japan was fear of surgery, whereas in the US and EU5 the main reason given was that surgery was not needed. This finding was also evident among physicians in Japan, who frequently reported that patient reluctance was a key reason for delaying surgery. Physicians in Japan, do however, report that patient request was one of their main triggers for recommending surgery (45% vs 20% US; 16% EU5).Conclusion:Although surgery can be an effective option for those with OA who have exhausted other treatment options, some patients are reluctant to undergo surgery out of fear, especially in Japan, possibly due to the higher patient age. Physicians aiming to delay surgery were driven by patient reluctance in Japan, whereas cost to patient was a bigger factor in the US and EU5. The higher level of TJR vs. other surgery options among patients in Japan may suggest physicians are looking for higher levels of efficacy.Disclosure of Interests:Naoshi Fukui Speakers bureau: Pfizer, Consultant of: Pfizer, Philip G Conaghan Speakers bureau: Abbvie, Novartis, Consultant of: AstraZeneca, BMS, Eli Lilly, EMD Serono, Flexion Therapeutics, Galapagos, Gilead, Novartis, Pfizer, Kanae Togo Shareholder of: Pfizer, Employee of: Pfizer, Nozomi Ebata Shareholder of: Pfizer, Employee of: Pfizer, Lucy Abraham Shareholder of: Pfizer, Employee of: Pfizer, James Jackson: None declared, Jessica Jackson: None declared, Mia Berry: None declared, Hemant Pandit Paid instructor for: Bristol Myers Squibb, Consultant of: Johnson and Johnson, Grant/research support from: GSK