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Avascular Necrosis

Avascular necrosis results from the temporary or permanent loss of blood supply to the bones. Although it can happen in any bone, avascular necrosis tends to affect the ends of long bones such as the femur. Causes of avascular necrosis include injury or long-term use of steroid medicines or alcohol. As the disease progresses, symptoms can include joint pain, limited range of movement, and osteoarthritis.

 

Avascular Necrosis: An Introduction

Avascular necrosis is a disease resulting from the temporary or permanent loss of the blood supply to the bones. Without blood, the bone tissue dies and causes the bone to collapse. If the process involves the bones near a joint, it often leads to collapse of the joint surface.
 
Avascular necrosis is also known as:
 
  • Osteonecrosis
  • Aseptic necrosis
  • Ischemic bone necrosis.
     

Understanding Bone Rebuilding and Avascular Necrosis

The process of bone rebuilding takes place after an injury as well as during normal growth. Normally, bone continuously breaks down and rebuilds -- old bone is reabsorbed and replaced with new bone. The process keeps the skeleton strong and helps it to maintain a balance of minerals.
 
In the course of avascular necrosis, however, the healing process is usually ineffective and the bone tissues break down faster than the body can repair them. If left untreated, avascular necrosis progresses, the bone collapses, and the joint surface breaks down, leading to pain and arthritis.
 
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Written by/reviewed by: Arthur Schoenstadt, MD
Last reviewed by: Arthur Schoenstadt, MD