Total hip replacement (THR) is often used for people suffering from the pain and dysfunction caused by arthritis of the hip. Infection of the hip prosthesis has been reported in about 1 percent of people who undergo THR. Exchange arthroplasty—surgical removal and replacement with another hip prosthesis—is often advocated, but this approach involves two major surgical procedures, often results in complications, and is costly.
Another approach is debridement (surgical cleaning and removal of infected tissue) of the infected prosthesis, but this is associated with high rates of reinfection. Nevertheless, debridement rather than replacement of a nonloosened, infected hip prosthesis is a better approach for elderly and frail elderly patients, concludes a study supported by the Agency for Healthcare Research and Quality (National Research Service Award training grant T32 HS00020).
The researchers found that debridement and retention of the infected prosthesis for these patients was associated with 2.2 to 2.6 more months in quality-adjusted life expectancy than replacement of the prosthesis in all groups. This is similar to the life expectancy gains with chemotherapy for non-small-cell lung cancer and the use of beta-blockers by men who have survived a heart attack, notes David N. Fisman, M.D., of Beth Israel Deaconess Medical Center in Boston.
Dr. Fisman and colleagues developed a model to simulate the initial management, clinical course, and later complications of an infected hip prosthesis to evaluate the cost-effectiveness of these two strategies—two-stage exchange arthroplasty or open debridement of the hip prosthesis followed by 6 weeks of antibiotic therapy—for managing infected THRs in hypothetical groups of 65-year-old men and women and frail 80-year-old men and women.
For 65-year-old men, a strategy of debridement and retention increased total lifetime costs by $3,600 and increased quality-adjusted life expectancy by 2.2 months, resulting in an incremental cost-effectiveness ratio of $19,700 per quality-adjusted life year (QALY) gained compared with initial hip replacement. Results were similar for 65-year-old women, for whom debridement and retention cost $21,800 per QALY gained. This same strategy for the frail elderly groups was associated with an incremental cost-effectiveness ratio of $500 per QALY for men and $8,200 per QALY for women.
For more details, see "Clinical effectiveness and cost-effectiveness of 2 management strategies for infected total hip arthroplasty in the elderly," by Dr. Fisman, Donald T. Reilly, Adolf W. Karchmer, and Sue J. Goldie, in the February 1, 2001 Clinical Infectious Diseases 32(3), pp. 419-430.