Aim: To determine the cost of medical treatment of infection following total joint replacement (TJR) of the hip or knee. With this information, and obtaining the current costs of antibiotics, antibiotic loaded cement and laminar flow theatres, we aimed to calculate the relative cost- benefit of these prophylactic strategies to prevent infection

Method: Fifty two patients who were admitted to The Canberra Hospital (TCH) for treatment of infection at following total joint arthroplasty between January 1996 and January 2001. A detailed cost analysis of treatment costs following infection was performed. All ward, theatre, prosthesis, investigation, pharmaceutical, allied health and medical costs were collated to produce a total cost of treatment. Current costs of prophylactic antibiotics, antibiotic cement and laminar flow theatres were obtained from suppliers. Costs were calculated for different combinations of prophylactic measures using the rates of deep periprosthetic infection reported through the Swedish Arthroplasty Registry.

Results: There were 41 deep infections and 13 superficial. The average cost for the 54 patients for the in hospital treatment of infection was $41,215. The cost of treating a superficial infection with antibiotics alone averaged $17,663. The average cost of a two stage revision procedure for deep periprosthetic infection was $79,623. Assuming a hospital volume of 150 cases per year, the use of prophylactic intravenous antibiotics, the use of laminar flow and the combined use of antibiotics and laminar flow were significantly cost effective. The addition of antibiotic loaded cement was marginally cost ineffective in combination with either or both of intravenous antibiotics or laminar flow.

Conclusion: The in hospital costs for the treatment of infection after TJR in the Australian setting have been addressed for the first time. Past studies have underestimated the cost of treatment. With this information, we have shown that the combinations of laminar flow and intravenous antibiotic for prophylaxis against infection in TJR are justified on a purely financial cost benefit basis.