Sex differences in clinical need, willingness, and surgeon recommendations for total knee arthroplasty: a cross-sectional study

OBJECTIVE: Females experience greater severity of knee osteoarthritis (OA) than males, but are disproportionately less likely to receive total knee arthroplasty (TKA). We examined whether sex differences in willingness to undergo TKA at surgeon consultation contributed to sex disparities. METHODS: This cross-sectional study was nested in a prospective cohort of knee OA patients referred to Alberta, Canada, hip/knee surgery clinics from 2014 to 2017. A pre-consult questionnaire assessed TKA appropriateness and contextual factors. TKA willingness was defined as responding 'yes' to "I would definitely consider having TKA now". Surgeon's reported their TKA recommendation (yes/no) postconsultation. Multivariable logistic regression models examined the association of patient sex with TKA willingness (yes/no) and multivariable log Poisson regression models assessed the association of willingness with receipt of a surgeon recommendation for TKA, stratified by sex. Models were adjusted for TKA appropriateness (need, psychological readiness, expectations, health status) and contextual factors. RESULTS: 2,035 participants were included (58.72% female; mean age 65.7 years [SD, 9.1]). Adjusting for TKA appropriateness and contextual factors, the odds ratio associated with a female versus a male being 'willing' was 0.67 (0.51 - 0.88). 1,518 (74.59%) participants were recommended TKA. The adjusted risk ratio associated with a 'definitely willing' individual being recommended TKA was 5.03 (95% CI 3.04 - 8.33) in males and 2.15 (95% CI 1.68 - 2.75) in females. CONCLUSION: Willingness to undergo TKA was associated with a higher likelihood of being recommended for TKA among males than females, raising concerns regarding bias.