Activity of fixed direct electrical current in experimental Staphylococcus aureus foreign-body osteomyelitis.

Fixed DC was compared to ceftriaxone, ceftriaxone with 200 μA fixed DC, or no treatment in a rat model of methicillin-susceptible Staphylococcus aureus foreign-body osteomyelitis. After 3 weeks, fewer bacteria were present in bones of the ceftriaxone group (5.71 log10 cfu/g [P = 0.0004]) and the ceftriaxone/DC group (3.53 log10 cfu/g [P = 0.0002]) than untreated controls (6.70 log10 cfu/g). Fewer bacteria were present in the ceftriaxone/DC group than in the ceftriaxone-alone and DC-alone groups (P = 0.0012 and 0.0008, respectively). There were also fewer bacteria on the implanted wires in the groups treated with ceftriaxone (5.47 log10 cfu/cm2 ) or ceftriaxone/DC (2.82 log10 cfu/cm2 ) than in the untreated controls (6.44 log10 cfu/cm2 [P = 0.0003 and 0.0002, respectively]). There were fewer bacteria in the ceftriaxone/DC rats than in the ceftriaxone-alone- and fixed DC-alone-treated rats (P = 0.0017 and 0.0016, respectively). Fixed DC with an antibiotic may be useful for treating foreign-body infections caused by S. aureus.