Refractory osteomyelitis is defined as acute or chronic osteomyelitis that is not cured after appropriate interventions. More often than not, refractory osteomyelitis is seen in patients whose systems are compromised. This condition often results in nonhealing wounds, sinus tracts, and, in the worst case, more aggressive infections that require amputation.
Mader and Niinikoski showed that hyperbaric oxygen therapy (HBOT) is capable of elevating oxygen tension in infected bone to normal or above normal levels. Since polymorphonuclear (PMN) function requires adequate oxygen concentration, this is a significant mechanism by which HBOT helps to control osteomyelitis, as demonstrated by Mader in the same study.
A unique mechanism by which HBOT is beneficial in osteomyelitis is in promoting osteoclast function. The resorption of necrotic bone by osteoclasts is oxygen-dependent. This has best been demonstrated in animal models of osteomyelitis.
Additionally, as previously mentioned, HBOT facilitates the penetration or function of antibiotic drugs. Other properties of HBOT previously discussed, such as neovascularization and blunting the inflammatory response, likely provide additional benefit.
Convincing animal evidence supports the use of HBOT in the treatment of osteomyelitis. Clinical studies are somewhat problematic, however, because osteomyelitis has so many different presentations that comparisons become difficult. This is compounded by the small study sizes found in the literature. However, these observations do suggest benefit of HBOT for refractory osteomyelitis in humans.
One specific subset of osteomyelitis that merits special attention is malignant otitis externa. This progressive pseudomonal osteomyelitis of the ear canal can spread to the skull base and become fatal. Davis et al published a study of 17 patients with malignant otitis externa, all of whom demonstrated dramatic improvement with the addition of HBOT to standard surgical debridement and antibiotic therapy.
Adapted from https://emedicine.medscape.com/article/1464149-overview#a11