Pharmacokinetic study of cefodizime and ceftriaxone in sera and bones of patients undergoing hip arthroplasty.

The study was carried out to determine the concentrations of cefodizime (single 2-g intravenous [i.v.] dose) and ceftriaxone (single 2-g i.v. dose) in the sera and bones of 42 patients (18 women and 24 men) undergoing hip arthroplasty. The concentrations of cefodizime and ceftriaxone in cancellous and cortical bone appear to be related to the free levels in serum but not to the total levels in serum, so the concentrations of cephalosporins in bone must be compared with the free concentrations in serum. Both drugs diffuse well into bone, with concentrations exceeding the MIC at which 90% of the major pathogenic infecting organisms are inhibited.