Avascular Necrosis

Avascular necrosis or osteonecrosis is condition that result from temporary or permanent loss of blood supply to the bone.

Interruption of blood supply causes small breaks in the bone and eventually death of the bone.

Avascular necrosis may be caused by

• trauma,
• atherosclerosis,
• inflammation of blood vessels,
• poor blood circulation to the bone.

The most common cause of the disease is the long-term use of steroids.

It is most commonly seen in people in the age group of 30-60 years.

Treatment depends on the stage of necrosis. Avascular necrosis may have long-term effects. 

In the early stages of avascular necrosis, the condition remains asymptomatic. With the progress of the condition, it becomes painful.

Initially the pain is felt only when there is strain on the affected area. Pain become persistent over a period of time.

In the later stages of the condition, the bone and surrounding joint collapses, causing severe pain. Pain in the region may interfere with daily activities.

It may take few months to a year from the appearance of the first symptom to collapse of the bone.

Avascular necrosis is usually seen in

• hip bones,

and the pain is felt in

• thighs,
• buttocks,
• groin.

Loss of blood supply may also happen to

• shoulders,
• knees, hand,
• foot.

Avascular necrosis may happen on both the joints simultaneously, like both sides of hips.

Avascular necrosis is caused by loss of blood flow to a bone.

Blood supply to a region may be interrupted by

• Trauma to joints or bones that damages blood vessels. Radiation treatment also may cause weak bones and damage the blood vessel.

• Atherosclerosis or fat deposits on the walls of the blood vessel that reduce the flow of blood to the bones

• Certain conditions like Sickle cell anemia and Gaucher’s disease that reduces the blood flow to different regions including bones.

In some cases, the reason for interrupted or loss of blood flow is not known.

Making a diagnosis of Avascular Necrosis is done by several tests.

Physical examination helps to identify the tenderness in the joint, indicating loss of blood flow to the region.

Imaging tests help to locate the source of pain.

X-ray provides detailed images of the joints showing the changes in bone during the later stages of avascular necrosis.

MRI and CT scan also help to visualize the early changes in the bones due to avascular necrosis.

In bone scan, a radioactive material is injected into the blood vessel which helps to trace the structure of joints in the images. 

Treatment of Avascular Necrosis depends on the severity of bone loss. In the early stages of avascular necrosis medication and therapy helps in alleviating symptoms.

Some common medications used are

Non-steroidal anti-inflammatory medications (NSAIDs)

Are used to reduce pain and inflammation associated with the condition

Osteoporosis drugs

Indicated in slowing the progression of the disease

Cholesterol-lowering medications

Prevent the buildup of fat in the walls of the blood vessels, reducing the risk of avascular necrosis

Blood thinners

Prevents formation of blood clots in the blood vessels

Rest

Restricted physical activity that puts lesser strain on the affected bone or joint

Exercises

Physical therapy that improves the flexibility and strength of the joints. This also helps to improve the range of motion of the bones and joints.

Electrical stimulation

Electrical shocks stimulate the growth of new bones in the damaged area. The electrical stimulation is applied directly to the region using electrodes.

In advanced stages of the disease, surgery and other procedures are recommended. 

Core depression

Is a method in which the surgeon removes a small part from the inner region of the bone. This provides extra space for the movement of the bone and also stimulate the production of healthy tissues.

In a bone transplant

A graft from a healthy bone is transplanted in the affected area and this helps to strengthen the affected bone.

Osteotomy or bone shaping

Is a procedure in which a wedge-shaped bone is removed from the affected region to shift the weight off the damaged area.

In joint replacement

The damaged joint is replaced by metal or plastic parts. This is recommended when other conventional treatments are not helpful in controlling the symptoms.

Regenerative medicine treatment

Is a new procedure stem cells from the bone marrow are harvested from the bone marrow.

Risk of avascular necrosis can be prevented by

• Reducing alcohol use
• Managing cholesterol at optimal levels
• Monitor the use of steroid medications

Homeopathic remedies used for avascular necrosis include:

• Syphilinum,
• silicea,
• fluoric acid,
• aurum metallicum,
• symphytum,
• natrum sulph

Yoga and meditation improves overall health and help in reducing stress.

Consuming lot of fruits and vegetables in the diet is also helpful. 

Lifestyle modifications are necessary in order to cope with avascular necrosis.

Working with the physical therapist helps to improve the flexibility and strength of the affected joint.

It improves the range of motion and strength of the joints.

Having a healthy diet is important in improving overall health of the person. 

There are several risks and complications associated with Avascular necrosis.

Avascular necrosis worsens over a period of time.

Weak bones may collapse leading to severe pain.