Dysbaric osteonecrosis is a term used to describe aseptic or avascular bone necrosis due to ischemia caused by gas bubbles, although the exact mechanism is still a matter of controversy. Typically it is a disease of deep-sea professional divers but affects more often recreational divers as well. Most commonly are affected long bones of arm and leg. The symptoms develop after a delay lasting from several months to several years after decompression. Diaphyseal damages are painless. Pain and disability are related to the damage of joints. Possible are fracture and deterioration of head of humerus or femur. There has been no satisfactory conservative treatment so far. Surgical treatment is aimed to removal of necrotic bone, bone transplantation or joint immobilization. The best prevention of dysbaric osteonecrosis is recompression therapy in all cases of decompression sickness.
HBOT is usually provided in long series of up to 120 exposures, if not even longer. HBOT increases partial pressure of oxygen in tissues, thus preventing further deterioration of bone cells, causes vasoconstriction, thus lessening edema and enhances perfusion, stimulates neoangiogenesis, osteogenesis and lessens pain.
