Alternating magnetic fields (AMF) and linezolid reduce Staphylococcus aureus biofilm in a large animal implant model

We aimed to evaluate the effectiveness of alternating magnetic fields (AMF) combined with antibiotics in reducing Staphylococcus aureus biofilm on metal implants in a large animal model, compared to antibiotics alone. Metal plates were inoculated with a clinical MRSA strain and then implanted into thirty-three ewes divided into three groups: positive control, linezolid only, and a combination of linezolid and AMF. Animals had either titanium or cobalt-chrome plates and were sacrificed at 5 or 21 days post-implantation. Blood and tissue samples were collected at various time points post-AMF treatment. In vivo efficacy studies demonstrated significant biofilm reduction on titanium and cobalt-chrome implants with AMF-linezolid combination treatment compared to controls. Significant bacterial reductions were also observed in surrounding tissues and bones. Cytokine analysis showed improved inflammatory responses with combination therapy, and histopathology confirmed reduced inflammation, necrosis, and bacterial presence, especially at 5 days post-implantation. This study demonstrates that combining AMF with antibiotics significantly reduces biofilm-associated infections on metal implants in a large animal model. Numerical simulations confirmed targeted heating, and in vivo results showed substantial bacterial load reduction and reduced inflammatory response. These findings support the potential of AMF as a non-invasive treatment for prosthetic joint infections. •AMF combined with antibiotics significantly reduce biofilm on metal implants in vivo.•Experimental measurements validated numerical simulations of AMF heating on implants.•AMF combined with antibiotics reduced inflammation in large animal model.•AMF has potential as a non-invasive treatment for prosthetic joint infections.