Necrosis is the term used for denoting tissue death in the body. Death of tissue can occur due to insufficient blood supply or complete cut-off from blood supply. It can occur due to radiation, sudden injury and exposure to chemicals. The damage caused by necrosis is irreversible. If the tissue death occurs in the bone it is known as Avascular necrosis. It can cause tiny fractures inside the bone which may eventually cause bone collapse.
Blood supply to particular section of a bone would stop leading to avascular necrosis. In some cases the joint of particular bone gets dislocated causing necrosis. This can occur due to prolonged use of steroids and alcoholism. Often, the hip joint is affected by avascular necrosis and sometimes it can affect the upper leg, upper arm or knee bones. Bone needs continuous blood supply since it is a living tissue. Any interruption of blood can cause death of bone tissue. Avascualr necrosis is also called as osteonecrosis or aseptic necrosis.
Symptoms :
Pain in the joint is the only symptom of avascular necrosis. In the initial stages there will not be any sign, but as the disease progresses, the joint may get affected causing intense pain while making movements. Avascular necrosis does not occur overnight. It is a process that happens gradually causing tissue death in the bone. It might take months together or sometimes even a year for tissue death on the bone. It can affect hip joints, shoulder, upper arm or leg and even your foot. Severe pain is felt in the groin or thighs and you can feel the pain in both sides of the body.
Causes :
When normal blood supply to the bone is restricted or slowed down it can cause avascular necrosis. This can happen due to sudden trauma or injury and due to dislocation of joint. People who undergo hip joint surgery are prone to develop avascular necrosis. People who are taking chemo therapy for cancer can develop avascular necrosis since radiation can weaken the bones and joints interrupting regular blood supply.
Chronic (long term) use of corticosteroids is likely to cause avascular necrosis. Over consumption of alcohol can deposit fat particles into the blood vessels thus restricting normal blood flow to the bones. Inflammation on the arteries and blood clots inside can restrict blood supply to the bone leading to avascular necrosis. Certain medical conditions like Gaucher’s disease, pancreatitis, HIV infection and other autoimmune disorders can cause necrosis in bones.
Risk Factors :
Anyone can develop avascular necrosis, but is common in age group of 30-50 years. People who are alcoholic or involved in binge drinking, people who use steroid drugs for long duration and those who take osteoporosis medications like biphosphonates are prone to develop avascular necrosis. Certain medical issues like lupus, HIV, diabetes and autoimmune diseases can trigger avascular necrosis. Undergoing cancer treatment, undergoing dialysis and kidney transplant surgery makes you prone to avascular necrosis.
Tests :
Your doctor will check the affected joint by gently applying pressure over it. He would look for tenderness of joint. He may order for imaging tests like X-ray or bone scanning to get clear picture of tissue death in the bone.
Read more on Osteoporosis
Treatment :
Bone loss that has already occurred cannot be reversed, but by giving timely treatment, you can prevent further damage to the affected joint and bone. Your doctor may prescribe NSAIDs like Aleve or Advil to get quick relief from joint pain and inflammation. Osteoporosis drugs like Fosamax or Binosto can be given to reduce bone loss. Cholesterol controlling medications is given to prevent blood clots in the blood vessels.
- Surgery :
For severe cases surgical procedures like bone transplantation, core decompression or osteotomy can be done. This method is effective in strengthening the affected bone. For some people, joint replacement surgery is done using plastic parts.
Home Remedies :
Your doctor may advice you to take complete rest if you have avascular necrosis. You should avoid putting extra pressure on the affected bone or joint to prevent further damage. Practice certain stretching exercises recommended by your therapist to improve the joint motion. Electrical current can be given on the affected bone to promote fresh bone growth.
Prevention :
One cannot prevent avascular necrosis but can reduce the risk factors like drinking excess of alcohol and reducing weight.