Femoral head necrosis (FHN) is a condition in which the blood supply to the femoral head is compromised. This leads to cell death in the marrow and the bone, and interferes with the normal activity of osteoblasts and osteoclasts, and loss of the structural integrity of the femoral head. The treatment of the FHN is an unresolved orthopedic problem and multiple approaches are used for its management. HBO therapy makes oxygen available to marrow cells and facilitates the bone remodeling processes through edema reduction and angioneogenesis stimulation