MedlinePlus is a service of the National Library of Medicine (NLM), the world's largest medical library, which is part of the National Institutes of Health (NIH). It was built as an online health information resource for patients and their families and friends.
MedlinePlus presents high-quality, easy to understand, relevant health and wellness information that is trusted.
MedlinePlus at a Glance
- Offers information on health topics, human genetics, medical tests, medications, dietary supplements, and healthy recipes.
- Sourced from more than 1,600 selected organizations.
- Provides 40,000 links to authoritative health information in English and 18,000 links to information in Spanish.
- In 2018, 277 million users viewed MedlinePlus more than 700 million times.
Osteonecrosis
Osteonecrosis is a disease caused by reduced blood flow to bones in the joints. In people with healthy bones, new bone is always replacing old bone. In osteonecrosis, the lack of blood causes the bone to break down faster than the body can make enough new bone. The bone starts to die and may break down.
You can have osteonecrosis in one or several bones. It is most common in the upper leg. Other common sites are your upper arm and your knees, shoulders and ankles. The disease can affect men and women of any age, but it usually strikes in your thirties, forties or fifties.
At first, you might not have any symptoms. As the disease gets worse, you will probably have joint pain that becomes more severe. You may not be able to bend or move the affected joint very well.
No one is sure what causes the disease. Risk factors include :
- Long-term steroid treatment
- Alcohol misuse
- Joint injuries
- Having certain diseases, including arthritis and cancer
Doctors use imaging tests and other tests to diagnose osteonecrosis. Treatments include medicines, using crutches, limiting activities that put weight on the affected joints, electrical stimulation and surgery.
NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases
