A REVIEW OF HYPERBARIC OXYGEN THERAPY FOR AVASCULAR NECROSIS

Introduction: Avascular necrosis (AN) is the death of trabecular bone and bone marrow. Hyperbaric oxygen (HBO) treatment in the early stages of AN of the femoral head alleviates intraosseous pressure by increasing the tissue oxygen pressure, increases microcirculation by arranging the venous drainage, so is recommended for that patients' treatment plan. Recently, many clinical trials and experimental studies were conducted about the effects of HBO on AN. Aim: Current treatment modalities partially address a need for adequate remedy to this disease. Prosthetic surgery performed on patients due to AN may cause some medical problems in long term follow up. HBO treatment can bring a new modality option for AN. There is no much data on the efficacy of HBO therapy on disease healing and delay of implementation of prosthetic implants. The aim of this review was to evaluate and summarize the evidence for application of HBO as a treatment for AN. Methods: The study included 10 randomized studies found in databases including PubMed/MedLine, Science Direct, Web of Science, and Cochrane Central Register of Controlled Trials Databases. The keywords "hyperbaric* oxygen therapy" or "hyperbaric* oxygen treatment" and "avascular necrosis" or "aseptic necrosis" or "femoral head necrosis" were used, and no time frame was selected. Results: The studies covered in our work consisted of experimental, clinical, and case series assessments. Three were controlled, experimental studies, and seven were clinical trials, which are generally considered more valuable due to their power and study design. Studies were evaluated in three category title; primary outcomes, stage of disease and effectiveness. HBO therapy has been shown to be effective in all three categories. Conclusion: The incidence of patients with AN is increasing majorly due to some external factors, steroid and trauma. Although the existed literature is qualified, the number of articles about the effects of HBO on AN are still quite few in the electronic database. In order to evidently state the efficacy of HBO in AN, well designed, comprehensive, randomized studies are required.