Prevalence of Osteonecrosis in Different Parts of the World

Osteonecrosis is a major increasing health problem all over the world. It is the final stage of a number of conditions leading to bone death [1]. It has undergone several name changes. Several synonyms used are osteonecrosis, idiopathic osteonecrosis, aseptic necrosis, and ischemic necrosis of bone. Aseptic necrosis was initially used to differentiate the condition of osteonecrosis from bone infections. Avascular or ischemic necrosis presumed a homogeneous etiology and pathogenesis. The term osteonecrosis describes the main common aspect of bone death and is more neutral in its assumption of causation [2].