Avascular necrosis (osteonecrosis)

Description

Avascular necrosis is the death of bone tissue due to lack of blood supply. Also called osteonecrosis, it can lead to tiny breaks in the bones and cause the bone to collapse. The process usually takes months and even years.

The fracture of a bone or a dislocated joint can stop the flow of blood to a section of the bone. Avascular necrosis is also associated with long-term use of high doses of steroids and a lot of alcohol.

Anyone can be affected. But the condition is more common in people between the ages of 30 and 50 years.

Symptoms

Some people have no symptoms in the early stages of avascular necrosis. As the condition worsens, the affected joints may hurt the one at the time of putting weight on them. Finally, you can feel the pain, even when you are lying down.

The pain can be mild or severe. It usually develops gradually. The pain associated with avascular necrosis of the hip may be based in the groin, thigh, or buttock. In addition to the hip, the shoulder, the knee, the hand and the foot can be affected.

Some people develop avascular necrosis in both sides, as in both hips and both knees.

When to see a doctor

Consult your health care provider for the continued pain in any joint. Seek immediate medical attention for a possible broken bone or a dislocated joint.

Causes

Avascular necrosis occurs when blood flow to a bone is interrupted or reduced. A reduced blood supply can be caused by:

  • The joint or bone trauma. An injury, such as a dislocated joint, it can damage the blood vessels nearby. Cancer radiation treatments also can weaken the bone and the damage of the blood vessels.
  • The fatty deposits in the blood vessels. Fats (lipids), you can block the small blood vessels. This can reduce the flow of blood to the bones.
  • Certain diseases. Medical conditions, such as sickle cell disease and Gaucher disease, may also decrease blood flow to the bones.

Sometimes, the cause of avascular necrosis is not the result of a trauma is not fully understood. Genetics combined with the excessive use of alcohol, certain medications and other illnesses that may play a role.

Risk factors

Risk factors for the development of avascular necrosis include:

  • The Trauma. Injuries, such as hip dislocation or fracture, you may damage nearby blood vessels and reduce the flow of blood to the bones.
  • The use of steroids. The use of high doses of corticosteroids, such as prednisone, is a common cause of avascular necrosis. The reason is unknown, but some experts believe that corticosteroids can increase the levels of lipids in the blood, reducing the blood flow.
  • Drinking too much alcohol. Having several alcoholic beverages per day, for several years can also cause fatty deposits to form in blood vessels.
  • The use of bisphosphonates. The long-term use of medications to increase bone density could contribute to the development of osteonecrosis of the jaw. This complication has occurred in some people treated with high doses of these drugs for cancer, such as multiple myeloma and metastatic breast cancer.
  • Certain medical treatments. Radiation therapy for cancer can weaken the bones. Transplants of organs, especially the kidney transplants, are also associated with avascular necrosis.

Medical conditions associated with avascular necrosis include:

  • Pancreatitis
  • Gaucher disease
  • HIV/AIDS
  • Systemic Lupus erythematosus
  • Sickle cell anemia
  • Decompression sickness, also known as divers of the disease or the bends
  • Certain types of cancer, such as leukemia

Complications

This is not, avascular necrosis worsens. Finally, the bone can collapse. Avascular necrosis also causes the bone to lose its soft form, possibly leading to severe arthritis.

Prevention

To reduce the risk of avascular necrosis and to improve the health in general:

  • Limit the consumption of alcohol. Excessive alcohol consumption is one of the main risk factors for the development of avascular necrosis.
  • Keep cholesterol levels low. Small pieces of fat are the most common substance to the blockage of blood supply to the bones.
  • To monitor the usage of steroids. Make sure that your health care provider about their past or present use of high-dose steroids. Steroid-related damage in the bone seems to get worse with repeated courses of high-dose steroids.
  • Do not smoke. Smoking narrows the blood vessels, which can reduce the flow of blood.

Avascular necrosis (osteonecrosis)

Diagnosis

During a physical exam, a health care provider of the press around the joints, checking for tenderness. You can also move the joints through different positions to see if the range of movement is less.

Imaging tests

Many conditions can cause pain in the joints. Imaging tests can help identify the source of the pain. Tests may include:

  • The x-ray. They can reveal changes in bone that occur in the later stages of avascular necrosis. In the condition's early stages, X-rays usually do not show any kind of problems.
  • The magnetic resonance imaging and computed tomography. These tests produce detailed images that can show early changes in the bone that may indicate avascular necrosis.
  • Bone scan. A small amount of radioactive material that is injected into a vein. This travels to the parts of the bones that are injured or healing. It shows up as bright spots on the plate of the image.

Treatment

The goal is to prevent the loss of bone.

Drugs

In the early stages of avascular necrosis, certain medications may help relieve the symptoms:

  • Nonsteroidal anti-inflammatory drugs (Nsaids). Over-the-counter medications such as ibuprofen (Advil, Motrin IB, others) or naproxen sodium (Aleve) may help relieve the pain associated with avascular necrosis. Stronger anti-inflammatory drugs (Nsaids) are available with a prescription.
  • Medications for Osteoporosis. These types of medications can slow the progression of avascular necrosis, but the evidence is mixed.
  • Medications to reduce cholesterol. Reduce the amount of cholesterol and fat in the blood can help to prevent blockages in blood vessels that can cause avascular necrosis.
  • Drugs that open the blood vessels. Iloprost (Ventavis) could increase the flow of blood to the affected bone. More studies are needed.
  • A blood thinner. For coagulation disorders, blood thinners, such as warfarin (Jantoven), could prevent the formation of blood clots in the vessels that supply blood to the bones.

Therapy

Your health care provider may recommend:

  • Rest. The restriction of the physical activity or the use of crutches for several months, to keep the weight on the joint may help to reduce the damage to the bones.
  • Exercises. A physical therapist can teach you exercises to help maintain or improve the range of motion in the joint.
  • The electrical stimulation. The electrical currents that could encourage the body to grow new bone to replace the damaged bone. The electrical stimulation can be used during the surgery and is applied directly to the damaged area. Or may be administered through electrodes attached to the skin.

Surgical and other procedures

Because most of the people do not have symptoms until the avascular necrosis is advanced, your health care provider may recommend surgery. The options include:

  • Core decompression. A surgeon removes part of the inner layer of the bone. In addition to reducing pain, the extra space on the inside of the bone activates the production of healthy bone tissue and new blood vessels.
  • Bone transplant (graft). This procedure can help to strengthen the area of the bone affected by avascular necrosis. The graft is a section of healthy bone taken from another part of the body.
  • The remodeling of bone (osteotomy). A wedge of bone is removed above or below a weight-bearing joint, to help shift the weight of the damaged bone. The bone remodeling may help postpone the replacement of the joint.
  • The replacement of the joint. If the affected bone has collapsed or other treatments are not helping, surgery can replace the damaged parts of the joint with plastic or metal parts.
  • Regenerative medicine in the treatment. Bone marrow aspiration and concentration is a new procedure that can help to avascular necrosis of the hip in the early stages. During the surgery, the surgeon removes a sample of the dead hip bone and the insertion of the stem cells extracted from the bone marrow in his place. This could allow the new bone to grow. More studies are needed.

Preparing for your appointment

Your health care provider may refer you to a doctor who specializes in disorders of the joints (rheumatologist) or an orthopaedic surgeon.

What you can do

Make a list of:

  • Its symptoms, including those that may seem unrelated to the reason for which you scheduled the appointment, and when they began
  • Key medical information, including other conditions you have and the history of the injury of the joint that hurts
  • All the medications, vitamins, or other supplements you are taking, including dose
  • Questions to ask your provider

Ask a relative or friend to accompany you, if possible, to help you remember the information that you receive.

Some questions to ask your provider about avascular necrosis include:

  • What is the most likely cause of my symptoms?
  • What tests do I need?
  • What treatments are available?
  • I have other health conditions. How can I best manage them together?

Do not hesitate to ask other questions.

What to expect from your doctor

Your provider is likely to ask questions such as:

  • Where is the pain?
  • Makes a joint in a particular position to make the pain better or worse?
  • Have you ever taken steroids such as prednisone?
  • How much alcohol do you drink?
Symptoms and treatment of Avascular necrosis (osteonecrosis)