Avascular Necrosis (Osteonecrosis): Symptoms, Causes, Diagnosis & Treatment — Complete Guide
Updated: 3 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026
Quick Answer: What Is Avascular Necrosis?
Avascular necrosis, also called osteonecrosis, is the death of bone tissue caused by a loss of blood supply, which can make the bone weaken and collapse. The hip is most often affected, and it is linked to joint injuries, long-term high-dose steroids and heavy alcohol use. MRI and CT can catch it early, and treatment can stop the damage.
What the research says
Higher steroid doses carry a higher risk of osteonecrosis. In a meta-analysis of 57 studies (23,561 patients), osteonecrosis incidence was 6.7% with corticosteroid treatment above 2 g (prednisone-equivalent); each 10 mg/day increase was associated with a 3.6% increase in the osteonecrosis rate, doses above 20 mg/day carried a higher incidence, and people with lupus showed a positive correlation between dose and incidence. (Mont et al., J Arthroplasty, 2015) [3]
Adding a second treatment to core decompression lowers the chance of progression. In a meta-analysis of 20 studies covering 2,123 hips (768 treated with core decompression alone, 1,355 with core decompression plus another treatment), stage progression occurred in 20% of the combination group versus 36% with core decompression alone (OR 0.32, 95% CI 0.16–0.64), with lower odds of collapse (OR 0.32, 95% CI 0.17–0.61) and of conversion to total hip arthroplasty (OR 0.35, 95% CI 0.23–0.55) and no serious adverse events, although the studies were markedly heterogeneous. (Zhu et al., Bone Joint Res, 2021) [4]
Bone marrow stem cells plus core decompression may help early-stage hips, but the evidence is still weak. Across 16 reports (583 hips with added bone marrow cells, 468 with core decompression alone), later total hip arthroplasty was needed in 22.5% versus 42.3% (P = 0.001), though the authors describe the data as heterogeneous and poor. (Zhang et al., J Am Acad Orthop Surg, 2020) [5]
At a Glance
Aspect | Key Facts |
Also known as | Osteonecrosis |
What happens | Bone tissue dies from lack of blood supply, leading to tiny breaks and possible collapse |
Most common age | 30–50 years (anyone can be affected) |
Most common site | Hip (groin, thigh, or buttock pain); also shoulder, knee, hand, foot |
Early symptom | Often none — pain typically starts when putting weight on the joint |
Top risk factors | Joint trauma, high-dose steroids (prednisone), heavy alcohol use, radiation therapy |
Best early test | MRI and CT scan (X-rays usually normal in early stages) |
Treatment goal | Prevent further bone loss |
Main treatments | NSAIDs, blood thinners, rest/crutches, core decompression, bone graft, osteotomy, joint replacement |
Prevention | Limit alcohol, low cholesterol, monitor steroid use, don't smoke |
What Is Avascular Necrosis?
Bone is living tissue, and like every living tissue in your body, it depends on a constant supply of blood. When that supply is interrupted or reduced, the affected bone tissue begins to die. This condition is called avascular necrosis, meaning "death of bone without blood" — the medical synonym is osteonecrosis.
The process is gradual. It can take months to years for the starved bone to weaken, develop tiny breaks, and finally collapse. By the time symptoms appear, the damage is often already advanced — which is why understanding the risk factors matters so much.
Anyone can be affected. But the condition is most common in people between the ages of 30 and 50.
What are the symptoms of avascular necrosis, and why do they sneak up?
Some people have no symptoms in the early stages of avascular necrosis. This silent start is exactly what makes the condition tricky — the bone is dying long before you feel anything.
As the condition worsens, affected joints hurt only when putting weight on them. Eventually, the pain persists even when you're lying down. Pain can be mild or serious, and it usually develops gradually.
Symptom Stage | What Happens |
Early | Often no symptoms at all — the bone is already being damaged |
Worsening | Joint hurts when putting weight on it (standing, walking) |
Advanced | Pain even when lying down; pain can be mild or severe |
Where the pain shows up depends on the joint. Avascular necrosis of the hip usually centers on the groin, thigh, or buttock. Besides the hip, the shoulder, knee, hand, and foot can be affected.
One more pattern worth knowing: some people develop avascular necrosis on both sides — in both hips or both knees. If you've been diagnosed in one joint, the matching joint deserves attention too.
When to See a Doctor
The rule is simple: see your healthcare professional for ongoing pain in any joint. Seek immediate medical attention for a possible broken bone or dislocated joint — trauma is one of the main triggers of avascular necrosis, and prompt care protects the blood supply to the bone.
What causes avascular necrosis by cutting off blood supply to bone?
Avascular necrosis occurs when blood flow to a bone is interrupted or reduced. The underlying chain is always the same — starve the bone of blood, and the tissue dies. What differs is how the flow gets blocked.
Cause | How It Cuts Off Blood Flow |
Joint or bone trauma | An injury, such as a dislocated joint, can damage nearby blood vessels |
Radiation therapy | Radiation can weaken bone and harm blood vessels |
Fatty deposits in blood vessels | Fat (called lipids) can block small blood vessels, reducing flow to bones |
Certain diseases | Sickle cell anemia, lupus, antiphospholipid syndrome, and Gaucher disease, among others, can lessen blood flow to bone |
Sometimes the cause of non-traumatic avascular necrosis is not fully understood. In these cases, genetics combined with overuse of alcohol, certain medicines, and other diseases likely play a role.
Risk Factors: Who Should Watch Their Bones
Several factors raise the odds of developing avascular necrosis. The most important ones:
Trauma. Injuries such as hip dislocation or fracture can damage nearby blood vessels and reduce blood flow to bones.
Steroid use. Long-term use of high-dose corticosteroids, such as prednisone, is a common cause. The reason isn't fully known, but experts believe corticosteroids can increase lipid levels in the blood, reducing blood flow. Damage appears to worsen with repeated courses of high-dose steroids.
Heavy alcohol use. Having several alcoholic drinks a day for several years can cause fatty deposits to form in blood vessels — blocking the routes that feed the bone.
Bisphosphonate use. Long-term use of bone-density medicines might contribute to osteonecrosis of the jaw — a rare complication seen in people treated with high doses for cancers such as multiple myeloma and metastatic breast cancer.
Certain medical treatments. Radiation therapy can weaken bone. Organ transplants — especially kidney transplants — are also associated with avascular necrosis.
Associated medical conditions include pancreatitis, Gaucher disease, HIV/AIDS, systemic lupus erythematosus, sickle cell anemia, decompression sickness (diver's disease or the bends), and certain cancers such as leukemia. If you have one of these conditions, mention it to your doctor whenever joint pain appears.
What are the complications of avascular necrosis?
Untreated, avascular necrosis worsens. Eventually, the bone can collapse. The damaged bone also loses its smooth shape, which can lead to early and severe arthritis — painful joint damage years before arthritis would normally appear.
This is the central message of this condition: the earlier it is found, the more options you have for keeping the joint.
Which tests diagnose avascular necrosis?
During a physical exam, a healthcare professional will press around the joints, checking for tenderness. They may also move the joints through different positions to see if the range of motion is lessened.
Because many conditions cause joint pain, imaging tests pinpoint the source. The key insight: not all imaging sees avascular necrosis equally.
Test | What It Shows |
X-rays | Reveal bone changes in the later stages — usually show nothing in early stages |
MRI and CT scan | Detailed images that catch early changes indicating avascular necrosis |
Bone scan | A small amount of radioactive material injected into a vein travels to injured or healing bone, showing up as bright spots on the imaging plate |
If your X-ray looks normal but your risk factors and pain pattern suggest avascular necrosis, an MRI or CT scan is the test that will reveal what the X-ray misses.
How is avascular necrosis treated, from medicines to joint replacement?
The goal of treatment is to prevent further bone loss. Your care team matches the approach to how advanced the condition is.
Medicines for the Early Stages
Medicine Type | What It Does | Notes |
NSAIDs | Relieve pain (ibuprofen/Advil/Motrin IB, naproxen sodium/Aleve over the counter; stronger versions by prescription) | First-line symptom relief |
Osteoporosis drugs | May slow progression of avascular necrosis | Evidence is mixed |
Cholesterol-lowering drugs | Reduce cholesterol and fat in the blood to help prevent vessel blockages | Addresses the lipid-blocking mechanism |
Blood-vessel-opening medicines | Might increase blood flow to the affected bone | More study needed |
Blood thinners | Warfarin (Jantoven) may prevent clots in vessels feeding the bones | For clotting disorders |
Therapy
Rest is more powerful than it sounds: restricting physical activity or using crutches for several months to keep weight off the joint might slow the bone damage. A physical therapist can teach exercises to maintain or improve the range of motion in the joint.
Electrical stimulation is another option: electrical currents might encourage the body to grow new bone to replace the damaged bone. It can be applied directly to the damaged area during surgery, or delivered through electrodes attached to the skin.
Surgery and Other Procedures
Most people don't develop symptoms until avascular necrosis is advanced, so surgery is commonly recommended.
Core decompression. The surgeon removes part of the inner layer of bone. Besides reducing pain, the extra space inside the bone triggers the production of healthy bone tissue and new blood vessels.
Bone transplant (graft). A section of healthy bone taken from another part of your body is transplanted to strengthen the affected area.
Bone reshaping (osteotomy). A wedge of bone is removed above or below a weight-bearing joint to shift weight off the damaged bone — a move that can postpone the need for joint replacement.
Joint replacement. If the affected bone has collapsed or other treatments aren't helping, surgery replaces the damaged parts of the joint with plastic or metal parts.
Regenerative medicine treatment. Bone marrow aspirate and concentration is a newer procedure that may help avascular necrosis of the hip in early stages. During surgery, the surgeon removes a sample of dead hipbone and inserts stem cells taken from bone marrow in its place, which might allow new bone to grow. More study is needed.
How can avascular necrosis be prevented?
Avascular necrosis prevention focuses on keeping blood vessels healthy by limiting alcohol, keeping cholesterol low, monitoring steroid use and not smoking.
Limit alcohol. Heavy drinking is one of the top risk factors for developing avascular necrosis.
Keep cholesterol levels low. Tiny bits of fat are the most common substance blocking blood supply to bones.
Monitor steroid use. Make sure your healthcare professional knows about your past or present use of high-dose steroids — damage worsens with repeated high-dose courses.
Don't smoke. Smoking narrows blood vessels, which can reduce blood flow.
Frequently Asked Questions
What is the difference between avascular necrosis and osteonecrosis?
Avascular necrosis and osteonecrosis are the same condition — "avascular" means without blood vessels and "necrosis" means tissue death, so both names describe bone that dies from a lost blood supply. Avascular necrosis is the more common everyday term, while osteonecrosis is the broader medical term you'll see in records and imaging reports.
Who is most likely to get avascular necrosis?
Anyone can develop it, but it is most common in people between ages 30 and 50. Risk rises with joint injuries like hip fractures or dislocations, long-term use of high-dose corticosteroids such as prednisone, heavy alcohol use, radiation therapy, organ transplants, and conditions like sickle cell anemia, lupus, and decompression sickness in divers.
What are the first signs of avascular necrosis?
Often there are no signs at all in the early stages, which is why it can spread silently for months or years. The earliest typical symptom is joint pain when putting weight on it, progressing to pain even when lying down; hip involvement usually causes pain in the groin, thigh, or buttock, and the condition frequently affects both hips or both knees.
Can an X-ray detect avascular necrosis?
Usually not early on — X-rays typically show no problems in the early stages and only reveal bone changes later, after the damage has advanced. MRI and CT scans produce detailed images that can show the early changes indicating avascular necrosis, and a bone scan highlights injured areas as bright spots.
What treatments are available for avascular necrosis?
Early treatment focuses on preventing further bone loss with NSAID pain relievers, cholesterol-lowering or blood-thinning medicines, rest, crutches, physical therapy, and electrical stimulation. When the condition is advanced, surgical options include core decompression, bone grafts, bone reshaping (osteotomy), joint replacement, and newer regenerative stem-cell procedures.
How do I prevent avascular necrosis?
Four habits protect the blood supply to your bones: limit alcohol, since heavy drinking is a top risk factor; keep cholesterol levels low, because fatty deposits commonly block the small vessels feeding bone; let your doctor know about any past or current high-dose steroid use; and don't smoke, since smoking narrows blood vessels and reduces flow.
How should you prepare for an avascular necrosis appointment?
Your healthcare professional might refer you to a rheumatologist (a doctor who specializes in disorders of the joints) or to an orthopedic surgeon.
What You Can Do
Make a list of your symptoms, including those that seem unrelated to the reason you scheduled the appointment, and when they began. Gather your key medical information, including other conditions you have and any history of injury to the painful joint. Write down all medicines, vitamins, or other supplements you take, including doses. And prepare your questions for the healthcare team.
Ask a relative or friend to come to the appointment with you, if possible, to help you remember the information you receive.
Questions to ask your care team
What's the most likely cause of my symptoms?
What tests do I need?
What treatments are available?
I have other health conditions. How can I best manage them together?
Don't hesitate to ask other questions.
What your doctor is likely to ask
Where's your pain?
Does a specific joint position make the pain better or worse?
Have you ever taken steroids such as prednisone?
How much alcohol do you drink?
Conclusion
Avascular necrosis is a condition that rewards early attention: bone dies when its blood supply is cut off, and the silent early phase means risk factors — joint trauma, steroids, alcohol, and certain diseases — deserve watchfulness long before pain arrives.
In this guide you've learned how to recognize the weight-bearing pain pattern, why MRI beats X-ray for early detection, how the treatment ladder runs from medicines and therapy to core decompression, bone grafts, and joint replacement, and the four prevention habits that keep your bones fed with blood.
If you're living with conditions like sickle cell anemia or lupus — both linked to avascular necrosis — the related guides on sickle cell disease and lupus on rinnit.com can help you understand your full health picture.
Have you experienced ongoing joint pain or long-term steroid use? Leave a comment below — your story may help another reader act sooner.
This article is for general informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional with any questions you may have regarding a medical condition.
Related Reading
Hip X-Ray: What It Shows, Views Taken and What to Expect explains the X-ray views used to check the hip joint.
References
Mayo Clinic Staff. Avascular necrosis (osteonecrosis) — Symptoms and causes. Mayo Clinic. July 28, 2025. https://www.mayoclinic.org/diseases-conditions/avascular-necrosis/symptoms-causes/syc-20369859
Mayo Clinic Staff. Avascular necrosis (osteonecrosis) — Diagnosis and treatment. Mayo Clinic. July 28, 2025. https://www.mayoclinic.org/diseases-conditions/avascular-necrosis/diagnosis-treatment/drc-20369863
Mont MA, Pivec R, Banerjee S, et al. High-dose corticosteroid use and risk of hip osteonecrosis: meta-analysis and systematic literature review. J Arthroplasty. 2015;30(9):1506-1512.e5. PMID 25900167. https://doi.org/10.1016/j.arth.2015.03.036
Zhu S, Zhang X, Chen X, et al. Comparison of cell therapy and other novel adjunctive therapies combined with core decompression for the treatment of osteonecrosis of the femoral head: a systematic review and meta-analysis of 20 studies. Bone Joint Res. 2021;10(7):445-458. PMID 34313452. https://doi.org/10.1302/2046-3758.107.BJR-2020-0418.R1
Zhang C, Fang X, Huang Z, et al. Addition of bone marrow stem cells therapy achieves better clinical outcomes and lower rates of disease progression compared with core decompression alone for early stage osteonecrosis of the femoral head: a systematic review and meta-analysis. J Am Acad Orthop Surg. 2020;28(23):973-979. PMID 32118614. https://doi.org/10.5435/JAAOS-D-19-00816
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