"Osteo" refers to bone. "Necrosis" is the medical term for dead cells. Osteonecrosis is the death of bone cells.
Osteonecrosis happens when something, such as a bone injury, interferes with blood supply to a bone
Osteonecrosis most often happens after a bone injury, but it can happen on its own
It's most common in the hip, knee, and shoulder
Osteonecrosis near a joint can cause arthritis in that joint
Symptoms include pain and trouble moving the nearby joint
Doctors do x-rays or MRI
Doctors treat osteonecrosis with pain medicine and physical therapy and sometimes do surgery
Early diagnosis may prevent the need for surgery
Osteonecrosis happens when there is:
Many people don't think of bone as living, growing tissue but it is. Because bones are living tissue, they need a blood supply to deliver oxygen and nutrition. Without enough blood, bones die.
Decreased blood flow to a bone can:
Injuries that break a bone or dislocate a joint sometimes tear blood vessels that feed the bone. If the blood vessels don't heal properly, your bone won't get enough blood.
Sometimes you get osteonecrosis without having an injury. This is more likely if you:
Symptoms of osteonecrosis include:
Other symptoms depend on where the problem is. If you have osteonecrosis in your hip, for example, you’ll have pain down your thigh or in your buttocks. If you have osteonecrosis in a leg bone, you’ll limp and have pain while standing or walking.
Doctors may suspect osteonecrosis if you broke a bone but keep having pain after the bone should have healed. They also suspect it if you have bone or joint pain for a long time for no apparent reason, particularly if you've been taking corticosteroids or drinking too much alcohol.
To see if you have osteonecrosis, doctors will do imaging tests, such as:
There is no specific treatment for osteonecrosis. Doctors try to make you feel better by having you:
If the osteonecrosis is caught early and is in just a small area, the bone may heal on its own with time.
Sometimes you'll need surgery. There are different types of surgery:
If you have severe damage, you may need a total joint replacement, such as replacement of your hip.