The estimated magnitude and direct hospital costs of prosthetic joint infections in the United States, 1997 to 2004.

To estimate the number and cost of prosthetic joint infection hospitalizations in civilian US hospitals, we analyzed the 1997 to 2004 National Hospital Discharge Survey for the 996.66 International Classification of Diseases discharge code (infection or inflammatory reaction secondary to internal joint prosthesis). The annual number of such hospitalizations averaged 17 589 from 1997 to 2000 and 29 225 from 2001 to 2004. The annual adjusted diagnostic-related group cost for such infection increased from $195 million to $283 million (1997-2004). The mean diagnostic-related group reimbursement ($9034 per hospitalization) did not vary over time or by comorbidity. The nearly doubled number of prosthetic joint infection-related hospitalizations may have been caused by an increased implant rate, changes in patient population, implant procedures, or causative organisms.