Antibiotics in bone tissues. Methodological and practical aspects.

With regard to determination of antibiotic levels in bone, variance in results may be obtained as a consequence of type of the bones involved, degree of penetration of the drug used and of assay method performed. Measurements of antibacterial activity in bone from patients undergoing orthopaedic surgery were performed after preoperative treatment with doxycycline, lincomycin, clindamycin or cefuroxime. In performing the assay by the agar diffusion method, after extraction of the bone specimens in buffer according to classical systems, the concentrations of doxycyline were in the range of 0.05--0.6 microgram/g, clindamycin 0.4--4.9 microgram/g, lincomycin 1.7--2.9 microgram/g and of cefuroxine about 0.4 microgram/g. After electrophoresis in agarose-gel and followed by microbiological assay higher levels of these drugs were estimated possibly as a consequence of a diminution in the binding capacity of bone.