HOSPITAL-RELATED AND PATIENT-RELATED CHARACTERISTICS DETERMINING LENGTH OF HOSPITAL STAY FOR HIP AND KNEE REPLACEMENTS

Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are amo ng the most prestigious health care technologies. Their popularity has grown rapidly, and an increasing proportion of health care resources is allocated to them. We studied patient- and hospital-related factors that cause variation in a major determinant of hospital costs, the le ngth of hospital stay (LOS) for THA and TKA. We gathered data on 10,28 8 hip and 5,173 knee patients with primary or secondary arthrosis from the Finnish Arthroplasty Register, which we linked with the Finnish H ospital Discharge Register. Patient- and hospital-related variations i n LOS were explained using regression models. Of the patient-related f actors, complications caused the greatest prolongation of hospital sta y, but patient's age, gender, and charge category also influenced LOS. Hospital-related factors were major causes of LOS variation. In the h ospitals the average case-mix-adjusted LOS ranged from less than a wee k to 3 weeks. The number of arthroplasties performed in hospital was i nversely related to LOS. The within-hospital LOS figures for THA and T KA were strikingly similar and persistent.