Osteomyelitis represents an inflammatory process with a bacterial infection involving bone. Refractory osteomyelitis refers to failure to heal or recurrence despite adequate surgical and antibiotic therapy. Bacteria can get to bone following an injury or via the bloodstream from an infection in another part of the body and then travel to a bone. HBOT enhances oxygen-dependent leukocyte killing through the production of hydrogen peroxide and superoxide by providing increased oxygen tension in the hypoxic tissue. Optimal tissue oxygen tension enhances osteogenesis and neovascularization to fill the dead space with new bone and soft tissues. HBO has also been shown to enhance osteoaclastic activity to remove bony debris. Synergistic effects of HBO on bone healing with bone morphogenic protein (BMP) were also demonstrated. HBO has also been shown to potentiate the antimicrobial effects of aminoglycosides, and possibly sulpha drugs and vancomycin, in the killing of susceptible bacteria