Cost of joint replacement surgery for osteoarthritis: the patients' perspective

To address costs of total joint replacement surgery from the patients' perspective by determining patient out-of-pocket costs during the first year following joint replacement, and to explore whether health status presurgery or in the immediate 3 months postsurgery were determinants of costs. In light of the different outcomes experienced by patients with total knee replacement (TKR) and total hip replacement (THR), any differences in costs between the 2 groups were also explored.

Patients with osteoarthritis (OA) scheduled for primary unilateral TKR or THR surgery at 3 Sydney hospitals were approached. Patients completed questionnaires preoperatively to record expenses during the previous 3 months and health status immediately prior to surgery. Patients then maintained detailed prospective cost diaries and completed SF-36 and WOMAC Index every 3 months for the first postoperative year. Arthritis-specific cost inforrmation obtained in the diary included medications (prescription and nonprescription), visits to health professionals, tests (radiographs, scans, blood tests, etc), special equipment, alterations to house, and the use of private or community services.

Ninety-eight TKR and 76 THR patients provided cost details for their first postoperative year. For both THR and TKR patients, out-of-pocket costs fell considerably over the first postoperative year, and during the year the proportion of patients who experienced no out-of-pocket costs increased, as did the proportion who made no use of health services such as medical tests or visits to health professionals. Regression analysis for THR patients showed that pension status, preoperative SF-36 Physical Component Score, and 3-month postoperative WOMAC Function were significant independent predictors of postoperative costs. Regression analysis for TKR patients showed that presurgery WOMAC Stiffness and pension status were significant independent predictors of postoperative costs, indicating that those with greater stiffness had greater postsurgery costs and those on a pension had lower costs.

OA patients undergoing THR and TKR have substantial out-of-pocket costs presurgery, which fall dramatically over the first postoperative year. Poorer presurgery health status predicted greater expenditure during the first postoperative year, which might be taken into consideration when patients are making a choice about the timing of joint surgery.