LAUSR

Background: The literature suggests that women with knee osteoarthritis (OA) perceive greater disability and a lower functional level before total knee arthroplasty (TKA) and undergo surgery at a later stage of the disease than men, which could lead to worse postoperative outcomes (1). These differences have been attributed to differences in the interpretation of symptoms between men and women (2), yet little is known about expectations of the postoperative outcomes of TKA. Objectives: To compare the duration of symptoms before TKA and the preoperative expectations of postoperative outcomes of TKA between men and woman. Methods: Preoperative data from a multicenter cohort study on outcomes of primary TKA were used. Preoperatively, patients were asked to indicate the duration of symptoms to TKA (<1 year, 1-5 years, 5-10 years and >10 years). The Hospital for Special Surgery (HSS) Knee Replacement Expectations Survey was used to obtain information on expectations regarding postoperative pain relief, mobility and daily activities and improvement of quality of life (score range 0-100), with lower scores indicating higher expectations. In addition, the Knee injury and Osteoarthritis Outcome Score (KOOS), pain (Numeric Rating Scale, NRS), comorbidities and work-status were gathered. Differences between men and women regarding the duration of symptoms and preoperative expectations were examined by the means of the Chi-Square test and independent t-test and difference with the 95% Confidence interval (CI) respectively. Results: A total of 1543 patients, 556 men (mean age 71 (SD 8), 32.3% paid employment) and 987 women (mean age 71 (SD 9), 20.3% paid employment) were included. Women had more pain preoperatively than men, 5.3 (SD 3) versus 4.3 (SD 3) at rest and 7.1 (SD 2) versus 6.2 (SD 3) during activity, respectively. Furthermore, men scored better on each KOOS subscale compared to women. Overall the duration of symptoms was longer in men than women: <1 year: 11.3% versus 9.6%, 1-5 years: 38.8% versus 49.7%, 5-10 years: 18.3% versus 20.0% and > 10 years: 31.5% versus 20.7%. Finally, women had significantly higher expectations of postoperative TKA outcomes than men, 67.4 (SD 19) and 70.2 (SD 19), respectively (Mean Difference; 2.79, 95% CI 0.84-4.75). Conclusion: Preoperatively, men reported a longer duration of symptoms and had lower expectations of TKA outcomes than women. However, men seemed to perceive less symptoms and restrictions in daily activities despite a longer duration of symptoms. References [1] Katz JN, Wright EA, Guadagnoli E, Liang MH, Karlson EW, Cleary PD. Differences between men and women undergoing major orthopedic surgery for degenerative arthritis. Arthritis & Rheumatism: official Journal of the american College of Rheumatology. 1994;37(5):687-94. [2] Parsley BS, Bertolusso R, Harrington M, Brekke a, Noble PC. Influence of gender on age of treatment with TKA and functional outcome. Clinical Orthopaedics and Related Research®. 2010;468(7):1759-64. Disclosure of interests: None declared