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Alternative Names: Avascular Necrosis of Bone.
Osteonecrosis is the destruction of a bone (necrosis) often due to an inadequate supply of blood to a bone. It most commonly affects the joints and bones of the hips, knees and shoulder. It often occurs as a result of bone injuries or in conjunction with other diseases and conditions.
Incidence; Causes & Development
Osteonecrosis is a common progressive disorder that can occur at any age, but is more frequently seen in people between 30 and 60 years of age. Osteonecrosis of the hip is slightly more common in men while Osteonecrosis that affects the knees is seen three times more often in women. It is also more common in those people with rheumatic diseases (e.g., rheumatoid arthritis, systemic lupus erythematosus), steroid users (such as cortisone), alcoholics, diabetics, and skin divers who have experienced a rapid reduction of air pressure (bends).
Osteonecrosis is the death of bone tissue associated with various diseases. A common cause is trauma that can cause a dislocation or fracture of the neck of the femur bone. Bones may also be affected by the use of certain drugs such as corticosteroids (glucocorticoids), or radiation and chemotherapy used in treating cancer patients. Osteonecrosis may also be a complication of kidney transplantation, sickle cell disease, alcoholism and other disorders.
Osteonecrosis is a slowly progressive disease frequently caused by a reduction of blood flow to a bone causing the bone to crack and eventually collapse. This condition usually occurs as the result of other diseases, injuries or conditions.
Signs & Symptoms
Pain is the primary symptom. It is a chronic and mild pain, usually occurring when standing, walking or lifting. The pain becomes worse when weight bearing activities exert pressure on the bones or joints. The pain may progress, eventually occurring while at rest or even disturbing sleep. Other symptoms include muscle spasms, joint stiffness and limitation of motion. Osteonecrosis most commonly affects the head of the femoral bone but may also involve the head of the humerus bone, the round protruding area at the end of the femur bone (condyles), the shin bone (distal tibia) and ankle (talus).
Diagnosis & Tests
X-rays can be helpful in diagnosing Osteonecrosis and determining the extent of bone damage.
Symptoms of the following disorder may be similar to those of Osteonecrosis. Comparisons may be useful for a differential diagnosis:
Osteopetrosis is a combination of several rare genetically caused symptoms grouped together as one disorder. It can be inherited as either a dominant or recessive trait and is marked by increased bone density, brittle bones, and in some cases skeletal abnormalities. Although symptoms may not initially be apparent to people with mild forms of this disorder, trivial injuries may cause bone fractures due to abnormalities of the bone. The dominantly transmitted form is milder than the recessive form and may not be diagnosed until adolescence or adulthood when symptoms first appear. More serious complications occur in the recessive form which may be diagnosed from examination of skeletal X-rays during infancy or childhood.
The following disorders may be associated with the development of Osteonecrosis. They are not necessary for a differential diagnosis:
Vasculitis is a common disorder characterized by an inflammation of the blood vessel walls. This inflammation causes a narrowing of the inside of the vessel and can obstruct the flow of blood to the tissues (ischemia). The lack of blood may cause damage to the tissues (necrosis), possible formation of blood clots (thrombosis), or a weakening or ballooning which can possibly cause a rupture of the vessel wall (aneurysm). Osteonecrosis can occur in people with vasculitis when blood flow has been obstructed to the bone or joint.
Rheumatoid Arthritis is an inflammatory autoimmune disease in which the body's natural defenses against foreign agents (antibodies & lymphocytes) attack healthy joints. This disorder is characterized by a lack of appetite (anorexia), fatigue, painful and deformed joints, early morning stiffness chiefly in the hands, knees, feet, jaw, and spine. People with Arthritis are at increased risk of also developing Osteonecrosis.
Lupus (also known as SLE or Systemic Lupus Erythematosus) is an inflammatory connective tissue disease that can affect many parts of the body including the joints, skin and internal organs. Lupus is a disease of the body's immune system, most often striking young women between the ages of 15 and 35 years. People who have Lupus are also at increased risk of developing Osteonecrosis.
Legg-Calve-Perthes Syndrome is a rare disease affecting the hip joint. Abnormalities in bone growth early in life may result in permanent deformity of the hip joint several years later. Osteonecrosis of the femoral head is often seen in those people with Legg-Calve-Perthes Disease.
Gaucher's Disease is an inherited disease of lipid metabolism caused by the failure to produce the enzyme glucocerebrosidase. It is the most common of the 14 known lipid storage disorders which includes Tay-Sachs, Fabry's Disease, and Niemann-Pick Disease. There are three types of Gaucher's Disease Type I, II and III. All three are characterized by the presence of Gaucher (lipid-laden) cells in the bone marrow and other organs such as the spleen and liver. Bone deterioration (Osteonecrosis) is a major symptom of this disease and can affect any part of the body.
Sickle Cell Disease is an inherited blood disease. Symptomatic of this disease are the "crisis periods" which often occur in conjunction with other infections. It is characterized by joint pain (arthralgia), fever, severe abdominal pain, vomiting, and damage to the head of the femur bone (osteonecrosis).
Polycythemia Vera is a chronic proliferative disorder of the bone marrow. It is characterized by an increase in the number of red blood cells (erythrocytosis) and hemoglobin concentration in the blood. Osteonecrosis can occur in Polycythemia Vera.
Caisson Disease, also called "Decompression Sickness" or the "Bends", is a disorder caused by the formation of nitrogen bubbles in the tissues and blood. This occurs from a very rapid reduction of air pressure after rising quickly from deep water with high atmospheric pressure, to normal air pressure. It is characterized by painful joints, bone deterioration (Osteonecrosis), chest tightness, giddiness, abdominal pain, vomiting and visual difficulties. In some with this disorder there may also be convulsions and paralysis.
Treatment & Prevention
Treatment of Osteonecrosis consists of diagnosing, treating or eliminating the underlying cause. Bones damaged or weakened by this disorder will usually heal and regenerate with appropriate treatment.
Limiting or avoiding alcohol, weight bearing activities, standing or walking may help in the recovery process. Bed rest and reducing stress to the affected area are helpful.
The pain associated with this disorder can be relieved with aspirin or non-steroidal anti-inflammatory drugs such as ibuprofen. Warm baths, heating pads and electric blankets may also be helpful in relieving the muscle spasms and pain associated with Osteonecrosis.
Surgery may be necessary when there is a dislocation, fracture or if the bone has collapsed. The most often used method of treatment for advanced Osteonecrosis of either the knee or hip is replacement of the affected area with a prosthetic joint.
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GLOSSARY
Abdomen (Abdominal)
That part of the body between the chest and the hips that contains the stomach, intestines, liver, bladder, pancreas and other organs.
Aneurysm
Localized enlargement of an artery.
Anorexia Nervosa (Anorexia)
An eating disorder characterized by excess control - a morbid fear of obesity leads the sufferer to try and limit or reduce their weight by excessive dieting, exercising, vomiting, purging and use of diuretics. Sufferers are typically more than 15% below the average weight for their height/sex/age and typically have amenorrhea (if female) or low libido (if male). 1-2% of female teenagers are anorexic.
Antibody (Antibodies)
A type of serum protein (globulin) synthesized by white blood cells of the lymphoid type in response to an antigenic (foreign substance) stimulus. Antibodies are complex substances formed to neutralize or destroy these antigens in the blood. Antibody activity normally fights infection but can be damaging in allergies and a group of diseases that are called autoimmune diseases.
Anti-inflammatory (Antiinflammatory)
Reducing inflammation by acting on body mechanisms, without directly acting on the cause of inflammation, e.g., glucocorticoids, aspirin.
Arthralgia
Severe throbbing or stabbing pain along a nerve in one or more joints.
Arthritis (Arthritic)
Inflammation of a joint, usually accompanied by pain, swelling, and stiffness, and resulting from infection, trauma, degenerative changes, metabolic disturbances, or other causes. It occurs in various forms, such as bacterial arthritis, osteoarthritis, or rheumatoid arthritis. Osteoarthritis, the most common form, is characterized by a gradual loss of cartilage and often an overgrowth of bone at the joints.
Autoimmune Disease (Autoimmune, Autoimmunity)
One of a large group of diseases in which the immune system turns against the body's own cells, tissues and organs, leading to chronic and often deadly conditions. Examples include multiple sclerosis, rheumatoid arthritis, systemic lupus, Bright's disease and diabetes.
Cancer
Refers to the various types of malignant neoplasms that contain cells growing out of control and invading adjacent tissues, which may metastasize to distant tissues.
Chemotherapy
A treatment of disease by any chemicals. Used most often to refer to the chemical treatments used to combat cancer cells. Chemotherapy is usually given in cycles: a treatment period followed by a recovery period, then another treatment period, and so on. Most anticancer drugs are given by injection into a blood vessel (IV); some are given by mouth. Chemotherapy is a systemic therapy, meaning that the drugs enter the bloodstream and travel throughout the body. Usually, a patient has chemotherapy as an outpatient (at the hospital, at the doctor's office, or at home). However, depending on which drugs are given and the patient's general health, a short hospital stay may be needed.
Chronic (Chronicity)
Usually referring to chronic illness: Illness extending over a long period of time.
Corticosteroid (Corticosteroids)
Steroid hormone produced by the adrenal cortex.
Diabetes Mellitus (Diabetes, Diabetic, Diabetics)
A disease with increased blood glucose levels due to lack or ineffectiveness of insulin. Diabetes is found in two forms; insulin-dependent diabetes (juvenile-onset) and non-insulin-dependent (adult-onset). Symptoms include increased thirst; increased urination; weight loss in spite of increased appetite; fatigue; nausea; vomiting; frequent infections including bladder, vaginal, and skin; blurred vision; impotence in men; bad breath; cessation of menses; diminished skin fullness. Other symptoms include bleeding gums; ear noise/buzzing; diarrhea; depression; confusion.
Distal
Anatomically located further away from a point of reference, such as an origin or a point of attachment.
Enzymes (Enzyme)
Specific protein catalysts produced by the cells that are crucial in chemical reactions and in building up or synthesizing most compounds in the body. Each enzyme performs a specific function without itself being consumed. For example, the digestive enzyme amylase acts on carbohydrates in foods to break them down.
Hemoglobin
The oxygen-carrying protein of the blood found in red blood cells.
Immune System (Immune Response, Immunity)
A complex that protects the body from disease organisms and other foreign bodies. The system includes the humoral immune response and the cell-mediated response. The immune system also protects the body from invasion by making local barriers and inflammation. The process may involve acquired immunity (the ability to learn and remember a specific infectious agent), or innate immunity (the genetically programmed system of responses that attack, digest, remove, and initiate inflammation and tissue healing).
Ischemia (Ischemic)
Localized tissue anemia due to obstruction of the inflow of arterial blood. A decrease in the blood supply to a bodily organ, tissue, or part caused by constriction or obstruction of the blood vessels.
Kidneys (Kidney, Renal)
Bean-shaped organs, each about the size of a fist. They are located near the middle of the back, just below the rib cage. The kidneys are sophisticated reprocessing machines, each day handling about 50 gallons of blood to sift out about half a gallon of waste products and extra water. The waste and extra water become urine, which flows to the bladder through tubes called ureters. The actual filtering occurs in tiny units inside the kidneys called nephrons. Every kidney has about a million nephrons. In a nephron, a glomerulus -- which is a tiny blood vessel, or capillary -- intertwines with a tiny urine-collecting tube called a tubule. A complicated chemical exchange takes place, as waste materials and water leave your blood and enter your urinary system. The kidneys recycle chemicals such as sodium, phosphorus, and potassium and thus regulate their levels. Renal: Pertaining to the kidneys.
Lipid (Lipids)
Fat-soluble substances derived from animal or vegetable cells by nonpolar solvents (e.g. ether); the term can include the following types of materials: fatty acids, glycerides, phospholipids, alcohols and waxes.
Liver (Hepatic)
The largest and one of the most complex organs of the body, the liver is responsible for much of the metabolism of fats, proteins and carbohydrates. It is the site of much of the body's detoxification. It is connected very closely with digestion and the regulation of blood sugar, among many other functions. Found behind the ribs on the right side of the abdomen, it has many important functions such as removing harmful material from the blood, making enzymes and bile that help digest food, and converting food into substances needed for life and growth. Hepatic: Pertaining to the liver.
Metabolism (Metabolic, Metabolize, Metabolizes, Metabolizing)
The chemical processes of living cells in which energy is produced in order to replace and repair tissues and maintain a healthy body. Responsible for the production of energy, biosynthesis of important substances, and degradation of various compounds. Also defined as the sum total of changes in an organism in order to achieve a balance (homeostasis): Catabolic burns up, anabolic stores and builds up; the sum of their work is metabolism.
Necrosis
Death of one or more cells, or of a portion of a tissue or organ.
Red Blood Cell (Erythrocyte, Erythrocytes, RBC, Red Blood Cells)
Any of the hemoglobin-containing cells that carry oxygen to the tissues and are responsible for the red color of blood.
Rheumatoid Arthritis
A long-term, destructive connective tissue disease that results from the body rejecting its own tissue cells (autoimmune reaction).
Spleen (Splenectomy)
The largest organ of the lymphatic system in the body, located between the stomach and the diaphragm (the muscle below the lungs which provides the motion for breathing). It destroys old red blood cells, produces lymphocytes and plasma cells, and stores blood. It also has other as yet unknown functions. A splenectomy is the surgical removal of the spleen.
Steroid (Steroids)
Any of a large number of hormonal substances with a similar basic chemical structure containing a 17-carbon 14-ring system and including the sterols and various hormones and glycosides.
Syndrome
A medical condition characterized by a collection of related symptoms (what the patient feels) and signs (what a doctor can observe or measure).
Thrombosis
Formation of blood clots causing vascular obstruction.
Vasculitis
Inflammation and necrosis of blood vessels, including arteries, veins and capillaries. The damage may be due to infectious agents, mechanical trauma, radiation or toxins; often no specific causative factor is identified. It involves immune mechanisms such as deposition of circulating immune complexes and direct attack by circulating antibodies
X-rays (X-ray)
High-energy radiation used to take pictures of areas inside the body.
Last updated: Oct 18, 2009
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