Аваскулярный некроз кости: причины, симптомы и лечение.

Death of bone tissue due to interruption of the blood supply

In many cases, there is pain and discomfort in a joint which increases over time. It can affect any bone, and for in about half of affected people, multiple sites are damaged. Avascular necrosis most commonly affects the ends of long bones, such as the femur. Other common sites include the humerus (upper arm), knees, shoulders,

The main risk factors are bone fractures, joint dislocations, alcoholism, and the use of high dose steroids. HIV infection, Gaucher's disease, and Caisson disease (dysbaric osteonecrosis). Bisphosphonates are associated with osteonecrosis of the mandible (jawbone). The condition may also occur without any clear reason. In children, avascular osteonecrosis can have several causes. It can occur in the hip as part of Legg–Calvé–Perthes syndrome, and it can also occur as a result after malignancy treatment such as acute lymphoblastic leukemia and allotransplantation.

When AVN affects the scaphoid bone, it is known as Preiser disease. Another named form of AVN is Köhler disease, which affects the navicular bone of the foot, primarily in children. Yet another form of AVN is Kienböck's disease, which affects the lunate bone in the wrist.

Other treatments include core decompression, where internal bone pressure is relieved by drilling a hole into the bone, and a living bone chip and an electrical device to stimulate new vascular growth are implanted; and the free vascular fibular graft (FVFG), in which a portion of the fibula, along with its blood supply, is removed and transplanted into the femoral head. A 2016 Cochrane review found no clear improvement between people who have had hip core decompression and participate in physical therapy, versus physical therapy alone. There is additionally no strong research on the effectiveness of hip core decompression for people with sickle cell disease.

The amount of disability that results from avascular necrosis depends on what part of the bone is affected, how large an area is involved, and how effectively the bone rebuilds itself. The process of bone rebuilding takes place after an injury as well as during normal growth. and the joint surface breaks down, leading to pain and arthritis. Avascular necrosis of the hip was also identified in a routine medical check up on quarterback Brett Favre following his trade to the Green Bay Packers in 1992. However, Favre would go on to have a long career at the Packers. Another high profile athlete was American road racing cyclist Floyd Landis, winner of the 2006 Tour de France, the title being subsequently stripped from his record by cycling's governing bodies after his blood samples tested positive for banned substances. During that tour, Landis was allowed cortisone shots to help manage his ailment, despite cortisone also being a banned substance in professional cycling at the time. Rafael Nadal successfully continued his tennis career after having surgery for Mueller–Weiss syndrome (osteonecrosis of the navicular.)