Readmissions after Diagnosis of Surgical Site Infection Following Knee and Hip Arthroplasty

CONTEXT: Surgical site infection (SSI) after total hip and knee arthroplasty is a common postoperative complication. We sought to determine readmission rates and costs for total hip and knee arthroplasty complicated by SSI. DESIGN: The Thomson Reuters MarketScan database was searched for patients who underwent knee or hip arthroplasty in 2007. From these data, patients who received a diagnosis of SSI and were readmitted after diagnosis were identified. SETTING: A population of 31 to 45 million individuals receiving insurance coverage. Patients who underwent knee or hip arthroplasty who experienced a hospitalization for SSI in the year after surgery were analyzed. OUTCOME MEASURES: Total readmission rates and costs per readmission at 30, 60, and 90 days and 1 year after diagnosis of SSI. RESULTS: Of the 76,289 case patients with hip or knee replacement in 2007, 1,026 (1.3%) had a hospitalization for SSI within the year after surgery. Among these patients, 310 (30.2%) were subsequently rehospitalized in the year after initial hospitalization specifically due to SSI-related issues. These rehospitalizations were associated with a mean hospital stay of [Formula: see text] days and a median cost of $20,001 (interquartile range [IQR], $14,057-$30,551). A total of 517 subjects had a subsequent "all-cause" hospitalization during the year after SSI. These rehospitalizations were associated with a mean hospital stay of [Formula: see text] days and a median cost of $19,870 (IQR, $13,913-$29,728). CONCLUSIONS: Readmissions during the year after SSI diagnosis accounted for 1,072 hospital admissions and cost over $25.5 million. These readmissions are costly and might be a future target for decreased reimbursement.