641 patients who underwent various operations after accidents or for orthopaedic treatment were treated prospectively with a single-shot dose of 750 mg cefuroxime. The infection rate was between 0,4 and 1,4% depending on the operation. Compared with the former treatment of 1,5 g cefuroxime, halving the dose did not cause any increase in the infection rate. In view of the statutory provisions (the Health Reform Law) and internal hospital budgeting, the prophylactically tested single dose of 750 mg is of great economic importance.