Aseptic necrosis is a condition in which bone tissue in a certain body part dies and breaks away because it does not receive a sufficient blood supply. Bone cell death usually occurs in large bones, such as the hip, shoulder, and knee, though smaller bones can also be affected. Aseptic necrosis can be caused by a number of environmental and genetic factors, especially direct trauma, alcohol abuse, and sickle cell anemia. The condition is progressive and can result in severe pain and debilitation if it goes untreated. Surgery is often necessary to graft healthy bone tissue to the affected area and promote healthy blood flow throughout the body.
Necrosis of bone tissue is usually the result of an injury that cuts off blood to a particular bone, as can occur with a fracture or dislocation. Blood supply can also be affected by fat deposits that build up in blood vessels after years of alcohol abuse. Corticosteroids can also lead to aseptic necrosis, though doctors are not sure exactly how they inhibit the blood supply. Other risk factors for aseptic necrosis include sickle cell anemia, lupus, blood clots, and familial history of bone or blood problems.
In many cases, there is no apparent cause of bone cell death. Doctors call such cases primary or idiopathic necrosis. Men are more likely than women to suffer from primary necrosis, and most instances appear in people over the age of 50. Older people are more likely to experience the condition since bones generally become more fragile and prone to degeneration as they age.
Most people who have the condition do not notice symptoms in the early stages. As larger numbers of bone cells die, an individual may notice pain and weakness in the affected area. The condition worsens over time, and eventually causes a loss of flexibility and mobility. It is possible for a bone to collapse completely in as little as five years, leaving the body part completely disabled. Early diagnosis and treatment of aseptic necrosis is vital to avoid permanent health problems.
If a doctor suspects aseptic necrosis, he or she can conduct x-rays, magnetic resonance imaging tests, and computerized tomography scans to get a clear picture of the bone and blood vessels. The doctor also tries to determine the underlying causes by conducting blood tests and asking patients about their medical histories and lifestyles. Treatment is usually geared towards the causes of aseptic necrosis to prevent further bone damage. A doctor may recommend that a patient stop using alcohol or corticosteroids, or receive treatment for anemia or other medical conditions.
Aseptic necrosis in its later stages is usually treated surgically. A surgeon can graft healthy bone tissue from a less essential part of the body onto the affected area. In many cases, it is necessary to realign bones to allow blood vessels to grow and function properly. If a bone is severely damaged, the surgeon may need to remove it completely and replace it with an artificial joint. Physical therapy and ongoing evaluations are important to ensure that patients fully recover.