Extracorporeal shockwave therapy in osteonecrosis of femoral head: A systematic review of now available clinical evidences

Zhang, Qingyu; Liu, Lihua; Sun, Wei; Gao, Fuqiang; Cheng, Liming; Li, Zirong

As is well-known, osteonecrosis of femoral head (ONFH) is a debilitating disorder with a considerably high incidence in the young and middle-aged (from the 20s to age 50), and consequently brings huge economic burden around the world. [1, 2] Approximately 20,000 patients were estimated to develop ONFH in America every year and another survey showed that the annul morbidity of ONFH in Japan was about 2.51/10,000. [3, 4] It is histologically characterized by insufficient supply of blood, death of osteocytes and bone marrow cells, and progressive structure damage of involved bones. Although osteonecrosis only affects the femoral head in most cases, osteonecrosis of other sites, for example, joints of knee, shoulder, wrist, elbow, and ankle also could be seen on clinic. The etiology of osteonecrosis is of various risk factors such as trauma, surgery of hip, corticosteroids, alcoholism, systemic lupus erythematosus, sickle-cell disease, and coagulopathy; [5] however, usually osteonecrotic lesions possess similar pathophysiological alteration.