Determining the need for hip and knee arthroplasty: The role of clinical severity and patients' preferences

BACKGROUND. Area variation in the use of surgical interventions such as art hroplasty is viewed as concerning and inappropriate. OBJECTIVES. To determine whether area arthroplasty rates reflect patient-re lated demand factors, we estimated the need for and the willingness to unde rgo arthroplasty in a high and a low-use area of Ontario, Canada. RESEARCH DESIGN. Population-based mail and telephone survey. SUBJECTS. All adults aged greater than or equal to 55 years in a high (n = 21,925) and low (n = 26,293) arthroplasty use area. MEASURES. We determined arthritis severity and comorbidity with questionnai res, established the presence of arthritis with examination and radiographs , and evaluated willingness to have arthroplasty with interviews. Potential arthroplasty need was defined as severe arthritis, no absolute contraindic ation for surgery, and evidence of arthritis on examination and radiographs , Estimates of need were then adjusted for patients' willingness to undergo arthroplasty. RESULTS. Response rates were 72.0% for questionnaires and interviews. The p otential need for arthroplasty was 36.3/1,000 respondents in the high-rate area compared with 28.5/1,000 in the low-rate area (P<0.0001), Among indivi duals with potential need, only 14.9% in the high-rate area and 8.5% in the low-rate area were definitely willing to undergo arthroplasty (P=0.03), yi elding adjusted estimates of need of 5.4/1,000 and 2.4/1,000 in the high- a nd low-rate areas, respectively. CONCLUSIONS. Demonstrable need and willingness were greater in the high-rat e area, suggesting these factors explain in part the observed geographic ra te variations for this procedure. Among those with severe arthritis, no mor e than 15% were definitely willing to undergo arthroplasty, emphasizing the importance of considering both patients' preferences and surgical indicati ons when evaluating need and appropriateness of rates for surgery.