Background: Many studies show gender and ethnic differences in healthcare utilization and outcomes. Patients' presurgical cognitions regarding surgical outcomes also may vary by gender and ethnicity and play a role in explaining utilization and outcome differences. However, it is unclear whether and to what extent gender and ethnicity play a role in patients' presurgical cognitions. Questions/Purposes: Do gender and ethnicity influence outcome expectations? Is arthroplasty-related knowledge affected by gender and ethnicity? Do gender and ethnicity influence willingness to pay for surgery? Methods: In a prospective, multicenter study we gave 765 patients an anonymous questionnaire on expectations, arthroplasty knowledge, and preferences before their consultation for hip and/or knee pain, from March 2005 to July 2007. Results: Six hundred seventy-two of the 765 patients (88%) completed questionnaires. Non-Hispanics and men were more likely to indicate they would be able to engage in more activities. Non-Hispanics and men had greater arthroplasty knowledge. Hispanics and women were more likely to report they would not pay for a total joint arthroplasty (TJA) relative to non-Hispanics and men. Conclusions: Sex and ethnic differences in patients presenting for their initial visit to the orthopaedists for hip or knee pain influence expectations, knowledge, and preferences concerning TJAs. Longitudinal study of relationships between patients' perceptions and utilization or outcomes regarding TJA is warranted.