Aseptic bone necrosis (ABN), also called avascular necrosis or osteonecrosis, is where bone and marrow die in the absence of an infective agent. It can affect any bone, and half of cases show multiple sites of damage, but primarily affects the joints at the shoulder, knee, and hip. Grays illustration of a human femur, a typically recognized bone. ... Grays Anatomy illustration of cells in bone marrow. ... An infection is the detrimental colonization of a host organism by a foreign species. ... The human upper arm Grays Fig. ... For other uses, see Knee (disambiguation). ... Bones of the Hip In anatomy, the hip is the bony projection of the femur, known as the greater trochanter, and the overlying muscle and fat. ...

The condition shows necrosis anywhere in the bone. Damage within the length of the bone is usually asymptomatic. Necrosis in the epiphysis or in the bone joints, which extends into adjacent cartilage is more serious. All dead bone cells are, eventually, reabsorbed and replaced. But new bone is soft, may misshape or fracture under pressure producing malformed joint surfaces and hence pain and mobility problems, afflictions such as arthritis. These joints must be treated surgically, by replacement. Necrosis (in Greek Νεκρός = Dead) is the name given to unprogrammed death of cells and living tissue. ... Cartilage is a type of dense connective tissue. ... Arthritis(from Greek arthro-, joint + -itis, inflammation) is a group of conditions that affect the health of the bone joints in the body. ...

It can be caused by a number of conditions that damage bone cells, including fractures, vascular compression, hypertension, vasculitis, thrombosis, the use of corticosteroids, and damage from radiation. For other forms of hypertension see hypertension (disambiguation). ... In medicine, vasculitis (plural: vasculitides) is a group of diseases featuring inflammation of the wall of blood vessels. ... Thrombosis is the formation of a clot or thrombus inside a blood vessel, obstructing the flow of blood through the circulatory system. ... In physiology, corticosteroids are a class of steroid hormones that are produced in the adrenal cortex. ... Radiation in physics is a process of emission of energy or particles. ...

It can also be found in divers, around 5% of professional divers develop ABN, as a consequence of inadequate decompression. Such decompression may be sufficient to prevent decompression sickness, but produces nitrogen bubbles that block blood circulation in some bone areas. A famous non-diving sports person with this condition is cyclist Floyd Landis, one of the top contenders for the 2006 Tour de France. Scuba divers. ... Decompresion has several meanings: in physics, decompression is the release of pressure and is the opposition of compression in medicine, scuba diving and aviation, decompression can refer to a sickness in scuba diving, decompression can refer to a stop, a chamber, a buoy, a trapeze, tables or a computer in... Decompression sickness (DCS), divers disease, the bends, or caisson disease is the name given to a variety of symptoms suffered by a person exposed to a reduction in the pressure surrounding their body. ... General Name, Symbol, Number nitrogen, N, 7 Chemical series nonmetals Group, Period, Block 15, 2, p Appearance colorless Atomic mass 14. ... This road bicycle is built using lightweight, shaped aluminium tubing and carbon fiber stays and forks. ... Floyd Landis (October 14, 1975, Farmersville, Lancaster County, Pennsylvania) is a professional road bicycle racer. ... The 2006 Tour de France is the 93rd Tour de France. ...

Avascular necrosis is especially common in the hip joint. A variety of methods are now used to treat avascular necrosis, the most common being the total hip replacement, or THR. However, THRs have a number of downsides including long recovery times and short life spans. THRs are an effective means of treatment in the geriatric population, however doctors shy away from using them in younger patients due to the reasons above. A new, more promising treatment is metal on metal resurfacing. It is a form of a THR, however in this procedure, only the head of the femur is removed as opposed to a THR in which the entire neck is removed. Metal on metal resurfacing is still experimental in America but has been endorsed in Great Britain as an excellent alternative to a THR. Some doctors also prescribe medicines such as Fosamax which are believed to increase the rate at which new bone replaces the dead bone, thus preventing collapse (specifically of the hip) due to AVN. Hip replacement is the most successful, cheapest and safest form of replacement surgery. ... Alendronate (Fosamax) is a bisphosphonate drug used for the treatment of osteoporosis (see Maturitas 2004; 48: 179-192). ...