Osteonecrosis is a disease caused by reduced blood flow to bones in the joints. With too little blood, the bone starts to die and may break down.
Osteonecrosis is also known as:
Osteonecrosis is most often found in the hips, knees, shoulders, and ankles. You may have osteonecrosis in one or more bones.
In people with healthy bones, new bone is always replacing old bone. This process keeps bones strong and also happens when children grow or if a bone is injured. In osteonecrosis, bone breaks down faster than the body can make enough strong, new bone. If you do not get treatment, the disease worsens and the bones in the joints break down. You may not be able to bend or move the affected joint very well, and you may have pain in the joint. If you want more info check out nonf.org