Patient Preferences for Surgical Treatment of Knee Osteoarthritis A Discrete-Choice Experiment Evaluating Total and Unicompartmental Knee Arthroplasty

Background: Total knee arthroplasty (TKA) is a common treatment for end-stage knee osteoarthritis but is associated with increased complication rates compared with unicompartmental knee arthroplasty (UKA). UKA offers better functional outcomes but is associated with a higher risk of revision. The purpose of this study was to apply good-practice, stated-preference methods to quantify patient preferences for benefit-risk tradeoffs associated with arthroplasty treatments for end-stage knee osteoarthritis. Methods: A discrete-choice experiment was developed with the following attributes: chance of complications, functional ability, awareness of the knee implant, and chance of needing another operation within 10 years. Patients included those aged 40 to 80 years with knee osteoarthritis. A pivot design filtered respondents into 1 of 2 surveys on the basis of self-reported functional ability (good compared with fair or poor) as measured by the Oxford Knee Score. Treatment-preference data were collected, and relative attribute-importance weights were estimated. Results: Two hundred and fifty-eight completed survey instruments from 92 males and 164 females were analyzed, with 72 respondents in the good-function cohort and 186 in the fair/poor-function cohort. Patients placed the greatest value or relative importance on serious complications and rates of revision in both cohorts. Preference weights did not vary between cohorts for any attribute. In the good-function cohort, 42% of respondents chose TKA and 58% chose UKA. In the fair/poor-function cohort, 54% chose TKA and 46% chose UKA. Conclusions: Patient preferences for various treatment attributes varied among patients in a knee osteoarthritis population. Complication and revision rates were the most important factors to patients, suggesting that physicians should focus on these areas when discussing treatments. The proportion of patients who chose UKA suggests that the current trend of increased UKA utilization is aligned with patient preferences.