Revision total knee arthroplasty complication rates in northern Illinois

A paucity of population-based data exist which describe the rapid growth of revision total knee arthroplasties, changes in patient characteristics, or the association of hospital volume with complication rates. We analyzed whether inpatient complications for 2986 revision knee arthroplasties done on patients admitted to 63 hospitals in northern Illinois from 1993-1999 were correlated with volume of revision total knee arthroplasties. Coded complication rates for hospitals with less than seven, seven to 14, or greater than 14 annual procedures were compared using logistic regression to control for clinical and demographic characteristics of patients, hospital teaching status, and the proportion of the hospitals' patients discharged to rehabilitation facilities. Revision total knee arthroplasties increased 59%, and the overall complication rate declined from 9.3% during 1993-1996 to 7.3% during 1997-1999 (p=.04). When compared with the lowest volume hospitals, medium-volume hospitals had higher complication rates, whereas the highest volume hospitals were not significantly different. The absence of volume-outcome effects may be related to the relatively high volume of primary knee arthroplasties done at almost all area hospitals, surgeon group coverage across multiple hospitals, and the small annual number of revision total knee arthroplasties done during these years.