An economic analysis of aseptic revision hip arthroplasty: calculation of partial hospital costs in relation to reimbursement.

INTRODUCTION: Aseptic loosening is one of the most common intermediate and long-term complications after total hip replacement (THR). These complications cause suffering and require expensive revision surgery. Little concrete data on direct costs are available from the hospital's, moreover operating department's perspective. We here provide a detailed analysis of the costs of THR revision and relate them to reimbursement underlying the German diagnosis-related groups (DRG) system. MATERIALS AND METHODS: Major cost parameters were identified using for orientation the cost matrix of the German Institute for Hospital Reimbursement (InEK GmbH). We then retrospectively analysed the major direct costs of aseptic revision THR in terms of contribution margins I and II. The analysis included a total of 114 patients who underwent aseptic revision from 1 January 2009 to 31 March 2012. Data were retrieved from the hospital information system and patient records. All costs of surgery, diagnostic tests, and other treatments were calculated as purchase prices in EUR. The comparative analysis of direct costs and reimbursements was done for DRG I46A and I46B from the hospital's, especially treating department's rather than the society or healthcare insurance's perspective. RESULTS: The average direct cost incurred by the hospital for a THR revision was 4,380.0. The largest share was accounted for surgical costs (62.7 % of total). Implant and staff costs were identified as the most important factors that can be influenced. The proportion of the daily contribution margin that was left to cover the hospital's indirect cost decreased with the relative cost weight of the DRG to which a patient was assigned. CONCLUSION: Our study for the first time provides a detailed analysis of the major direct case costs of THR revision for aseptic loosening from the provider's perspective. Our findings suggest that these revision operations could be performed cost-beneficially by the operating unit. From an economic perspective, cases with higher cost weights are more favorable for a hospital. These results need to be confirmed in multicenter studies.