Infection burden for hip and knee arthroplasty in the United States.

We quantified the current and historical incidence of periprosthetic infection associated with hip and knee arthroplasty in the United States using the Nationwide Inpatient Sample, as well as corresponding hospitalization charges and length of stay. The rate of infected knee arthroplasties was 0.92%, significantly greater than that of infected hip arthroplasties with 0.88%. Length of stay was significantly longer for infected hip (9.7 days) and knee (7.6 days) arthroplasties compared to uninfected procedures (hip, 4.3 days; knee, 3.9 days) (P < .0001). Hospitalization charges were also significantly greater for infected joint arthroplasties than for uninfected arthroplasties (hips, 1.76 times; knees, 1.52 times) (P < .0001). Urban-non-teaching hospitals experienced the highest burden of infection with 1.18% for hips and 1.26% for knees compared to rural (0.61% for hips and 0.69% for knees) and urban-teaching hospitals (0.73% for hips and 0.77% for knees). We found an increasing number of joint arthroplasties being diagnosed with periprosthetic infection.