Avascular Necrosis of the Femoral Head

Avascular necrosis of the femoral head means that part of the ball of the hip joint (the femoral head) dies because it does not get enough blood for a long time. “Avascular” means “without blood supply,” and “necrosis” means “tissue death.”

Avascular necrosis (AVN) of the femoral head happens when the blood supply to the ball part of the hip joint slowly gets blocked or damaged. Without enough blood, the bone cells die, the smooth round head of the femur becomes weak, and the surface can collapse. When this happens, the hip becomes painful, stiff, and often develops early osteoarthritis. Common risk factors are long-term or high-dose steroid use, heavy alcohol use, hip injury, sickle cell disease, clotting problems, and some autoimmune or metabolic diseases.[1]

Doctors also call this problem osteonecrosis of the femoral head, femoral head osteonecrosis, or just hip osteonecrosis. All these names describe the same idea: bone cells in the femoral head die from poor blood flow, and over time the round ball can weaken, flatten, and collapse.

In early stages, doctors try to protect the bone with activity changes, medicines, and bone-supporting treatments. In later stages, when the bone has already collapsed, surgery such as core decompression, bone grafting, or hip replacement is usually needed. The main treatment goals are to relieve pain, slow or stop the collapse of the femoral head, keep hip movement normal, and delay or avoid total hip replacement, especially in younger patients.[2]

When the femoral head collapses, the smooth joint surface becomes uneven. This causes pain, stiffness, and finally hip osteoarthritis. In more than 75% of all avascular necrosis cases in the body, the femoral head is the bone that is affected.

This disease often happens in adults who are in their 30s to 60s, but it can also occur in younger people, especially after injury or in some blood diseases. Both men and women can get it, and many people have both hips involved (bilateral disease).

Anatomy and blood supply of the femoral head

The hip joint is a “ball and socket” joint. The ball is the femoral head at the top of the thigh bone (femur). The socket is part of the pelvis, called the acetabulum. The surfaces are covered with smooth cartilage that lets the hip move easily.

Small blood vessels run up the neck of the femur and enter the femoral head. These are mostly tiny arteries that come from around the hip joint. If these vessels are blocked, narrowed, torn, or compressed, less blood reaches the bone cells in the femoral head.

When blood flow is not enough for some time, bone cells die, and the bone becomes weak. The body tries to repair the damage, but if the weak area is large, the round surface of the head can crack and sink (collapse). Walking on this weak bone makes the damage worse and leads to arthritis.

Types of avascular necrosis of the femoral head

Here “types” are simple ways doctors group this disease.

• Traumatic avascular necrosis – This type happens after a clear injury, such as a hip fracture or hip dislocation, which damages the blood vessels supplying the femoral head.

• Non-traumatic avascular necrosis – This type appears without a big injury. It is linked to things like long-term steroid medicine, heavy alcohol use, blood diseases, or unknown (idiopathic) causes.

• Early-stage (pre-collapse) avascular necrosis – In these stages the femoral head is still round. X-rays may look normal, but MRI already shows dead bone. Pain is often present but the joint surface is not yet broken.

• Late-stage (post-collapse) avascular necrosis – In these stages part of the femoral head has collapsed, the joint is irregular, and arthritis changes are visible on X-ray. Pain and disability are usually severe.

• Unilateral avascular necrosis – Only one hip is affected. This is more common after trauma on one side.

• Bilateral avascular necrosis – Both hips are affected, often with non-traumatic causes like steroids or alcohol. Doctors check the other hip carefully, even if it is not yet painful.

Causes

Each “cause” is a condition or factor that can damage blood supply or bone metabolism in the femoral head.

1. High-dose or long-term corticosteroid use
   Medicines like prednisone, taken in high doses or for a long time, are one of the most common non-traumatic causes. Steroids can change fat metabolism inside bone and blood, leading to fat build-up, small clots, and blocked vessels in the femoral head.

2. Heavy alcohol use
   Drinking large amounts of alcohol for many years can cause fatty deposits in blood vessels and damage bone cells. This raises the pressure in the bone and reduces blood flow, increasing the risk of femoral head necrosis.

3. Traumatic hip fracture
   A break in the neck of the femur can tear the small arteries that run to the femoral head. Even with good surgery, the blood supply may not recover fully, which can lead to avascular necrosis months or years later.

4. Traumatic hip dislocation
   When the ball of the hip pops out of the socket, the surrounding blood vessels can be stretched or torn. If the joint stays dislocated for a long time before reduction, the risk of permanent blood-flow loss and necrosis is higher.

5. Sickle cell disease and other hemoglobin disorders
   In sickle cell disease, red blood cells change shape and block small vessels, especially under low oxygen. These repeated blockages can cut off blood to the femoral head and cause AVN at a young age.

6. Systemic lupus erythematosus (SLE)
   People with lupus have both disease-related blood-vessel problems and usually receive high-dose steroids. Together, these factors make AVN of the femoral head more likely.

7. Gaucher disease
   In this metabolic disorder, abnormal storage cells accumulate in bone marrow and disturb blood flow. The femoral head is one of the common sites where bone infarction and osteonecrosis occur.

8. HIV infection and antiretroviral therapy
   Patients with HIV, especially those on some antiretroviral drugs or steroids, can develop lipid problems and clotting issues. This combination increases the risk of non-traumatic AVN of the femoral head.

9. After organ or bone marrow transplant
   Transplant patients often use high-dose steroids and other medicines that affect blood vessels and bone health. AVN of the femoral head is a known complication after kidney, liver, or bone marrow transplantation.

10. Coagulation and thrombophilia disorders
    Inherited or acquired conditions that make the blood more likely to clot (for example, antiphospholipid syndrome or factor V Leiden) can cause tiny clots in femoral head vessels and lead to necrosis.

11. Hyperlipidemia and metabolic syndrome
    High cholesterol and triglycerides, obesity, and metabolic syndrome can thicken vessel walls and encourage fat emboli. This worsens micro-circulation in the femoral head and increases AVN risk.

12. Smoking
    Smoking damages blood vessel lining, increases blood viscosity, and lowers oxygen delivery. These changes may contribute to femoral head ischemia, especially when combined with other risk factors.

13. Chemotherapy and cancer-related treatment
    Some chemotherapy drugs and radiation around the pelvis damage bone marrow cells and small vessels. Over time, this damage can lead to osteonecrosis of the femoral head in cancer survivors.

14. Radiation therapy to the hip or pelvis
    Radiation can cause scarring and narrowing in bone blood vessels and weaken the bone matrix. This radiation-induced injury may produce AVN months or years after treatment.

15. Legg–Calvé–Perthes disease in childhood
    This pediatric disorder is itself a form of avascular necrosis of the femoral head. Children who had Perthes disease can later have deformity and early degeneration of the same hip in adult life.

16. Decompression sickness (“the bends”)
    In divers or workers exposed to compressed air, nitrogen bubbles may form in blood and block small vessels, including those supplying the femoral head. This can cause multifocal AVN.

17. Pancreatitis and high blood lipid levels
    Severe inflammation of the pancreas can cause fat particles and inflammatory mediators to enter the bloodstream, damaging micro-circulation and sometimes leading to bone necrosis.

18. Idiopathic (unknown) causes
    In many patients, even after detailed tests, no clear cause is found. These cases are called idiopathic AVN. Doctors still think that hidden problems in blood clotting or fat metabolism may be involved.

19. Short-term but intense steroid courses
    Even relatively low or short courses of oral steroids have sometimes been linked with AVN in sensitive people. This shows that some individuals may have special susceptibility in their bone or blood-vessel biology.

20. Combined risk factors (for example, steroid plus alcohol)
    Often more than one risk factor is present, such as a person with autoimmune disease who uses steroids, drinks heavily, and smokes. These combined stresses greatly increase the chance of femoral head necrosis.

Symptoms

1. Deep hip or groin pain
   The most common symptom is a deep aching pain in the hip or groin. It often starts slowly and may be felt in the front of the hip crease. The pain comes from pressure inside the dying bone and irritated joint structures.

2. Pain that worsens with weight-bearing
   Pain usually becomes stronger when the person stands, walks, climbs stairs, or runs, because the weak femoral head is loaded. Rest or lying down often makes the pain better in early stages.

3. Pain that can radiate to thigh, buttock, or knee
   Many people feel pain not only in the groin, but also spreading to the front of the thigh, the buttock, or even the inner side of the knee. This is because nerves from the hip joint share pathways with these areas.

4. Limp while walking
   Because putting full weight on the affected hip is painful, patients often develop a limp. Sometimes family or friends notice that the person is limping before the patient fully understands the problem.

5. Stiffness and reduced range of motion
   The hip becomes stiff over time. Movements like bending the hip, rotating it inward, or spreading the legs apart become limited and painful as the joint surface becomes irregular.

6. Pain with certain movements (twisting, crossing legs)
   Activities such as sitting cross-legged, turning in bed, or twisting while standing can trigger sharp pain. These movements press damaged parts of the femoral head against the socket.

7. Mechanical symptoms (catching, locking, or clicking)
   When the joint surface becomes uneven or fragments of bone and cartilage are loose, patients may feel catching, locking, or a painful click during motion.

8. Night pain or rest pain in later stages
   In advanced disease, pain may appear even at rest or at night. This can disturb sleep and is often a sign that the femoral head has collapsed and arthritis has developed.

9. Difficulty standing for a long time
   Many patients cannot stand for long periods without pain. They may need to change position often or use support, especially when the hip is in the same posture for a long time.

10. Difficulty climbing stairs or walking uphill
    These actions put extra load on the hip joint. People with femoral head AVN often report early difficulty with stairs or ramps before flat walking becomes very painful.

11. Reduced walking distance
    Over months, many patients notice that they can walk shorter distances before needing to stop due to hip pain or fatigue. This limits daily activities and work.

12. Weakness of hip muscles
    Pain and disuse can cause the hip muscles, especially the abductors on the side of the hip, to weaken. This contributes to an unstable gait.

13. Positive Trendelenburg sign
    When standing on the affected leg, the pelvis may drop on the opposite side because the hip abductor muscles cannot hold it level. This clinical finding is called a positive Trendelenburg sign and is often seen in painful hip conditions.

14. Minimal or no symptoms in very early disease
    In some people, early AVN is found by chance on imaging when they are checked for another reason. The hip can look normal on X-ray and feel almost normal, even though MRI already shows dead bone.

15. Progressive disability and reduced quality of life
    As the disease advances, pain, stiffness, and limp together make many daily tasks hard, such as working, running, or even simple household activities. This long-term disability greatly affects quality of life.

Diagnostic tests

Doctors combine history, physical exam, and different tests to diagnose avascular necrosis of the femoral head and to see how severe it is.

Physical exam tests

1. Gait observation and limp assessment (Physical exam)
   The doctor watches how the person walks, looking for a limp, short stance on the painful leg, or use of a cane. A painful, shortened weight-bearing phase suggests hip joint problems such as AVN.

2. Inspection of posture and leg length (Physical exam)
   The hips, pelvis, and spine are inspected while the patient stands. In advanced disease, leg length difference or pelvic tilt may be seen, which can come from femoral head collapse or muscle imbalance.

3. Palpation of hip and groin (Physical exam)
   The examiner gently presses around the front of the hip and groin. Local tenderness here, along with deep joint pain on movement, supports that the hip joint, not the spine or knee, is the main source of pain.

4. Range of motion testing (Physical exam)
   The doctor bends (flexes), straightens (extends), rotates, and abducts the hip. In AVN, internal rotation and abduction are often limited and painful, especially near the end of the movement range.

Manual orthopedic tests

5. Trendelenburg test (Manual test)
   The patient stands on one leg while the doctor watches the pelvis. If the pelvis drops on the opposite side or if there is marked pain, the test is positive. This shows weakness or pain in the hip abductors, commonly seen in hip osteonecrosis and arthritis.

6. FABER (Patrick) test (Manual test)
   FABER stands for Flexion, ABduction, External Rotation. The ankle of the tested leg is placed on the opposite knee, forming a “figure-4,” and gentle pressure is applied. Pain in the hip or groin during this maneuver suggests hip joint pathology such as AVN.

7. FADIR test (Manual test)
   FADIR means Flexion, ADduction, Internal Rotation. The hip is bent to about 90 degrees, brought toward the midline, and rotated inward. This test compresses the femoral head in the socket. Pain may indicate intra-articular disease, including AVN and femoroacetabular impingement.

8. Resisted muscle strength testing (Manual test)
   The examiner asks the patient to push or pull against resistance in different directions (for example, lifting the leg or moving it outward). Weakness and pain, especially in abductors and flexors, give information about functional impact of the disease.

Lab and pathological tests

9. Complete blood count (Lab test)
   A complete blood count (CBC) looks at red cells, white cells, and platelets. It helps find blood disorders like sickle cell disease or leukemia, which can be linked with AVN or need to be ruled out.

10. Lipid profile (Lab test)
    Tests for cholesterol and triglycerides can show hyperlipidemia or metabolic syndrome. These conditions are associated with higher risk of femoral head necrosis and may also guide preventive treatment.

11. Coagulation and thrombophilia panel (Lab test)
    Blood tests such as PT, aPTT, and special assays for thrombophilia help detect clotting disorders. Finding abnormal clotting tendency supports a vascular cause for otherwise “idiopathic” AVN.

12. Autoimmune and inflammatory markers (Lab test)
    Tests like ANA, anti-dsDNA, ESR, and CRP help identify autoimmune diseases such as lupus and measure inflammation. These conditions and their treatments are strongly related to non-traumatic AVN.

13. Hemoglobin electrophoresis (Lab test)
    This test looks at the types of hemoglobin in the blood. It helps diagnose sickle cell disease and other hemoglobinopathies, which are important causes of AVN in younger patients.

14. Histopathological examination of bone (Pathological test)
    In some cases, a sample of bone (biopsy) is taken during surgery. Under the microscope, pathologists see dead bone cells, empty spaces, and repair tissue. This confirms osteonecrosis and can show its extent.

Electrodiagnostic tests

15. Electromyography (EMG) (Electrodiagnostic test)
    Although not used to diagnose AVN directly, EMG can help when there is doubt whether weakness and pain come from nerve disease or from the hip joint. Normal EMG with clear hip findings supports a joint source like AVN.

16. Nerve conduction studies (Electrodiagnostic test)
    These tests measure the speed and strength of signals in peripheral nerves. They are mainly used to rule out neuropathy or radiculopathy when symptoms are confusing, helping to focus attention back on structural hip problems if nerves are normal.

Imaging tests

17. Plain X-ray of the pelvis and hip (Imaging test)
    X-rays are often the first imaging test. In early AVN, X-rays may look normal, but later they can show sclerosis (whiter areas), cysts, and the “crescent sign,” which indicates a subchondral fracture, and finally collapse of the femoral head.

18. Magnetic resonance imaging (MRI) of the hip (Imaging test)
    MRI is the most sensitive and specific imaging tool for early AVN. It can detect bone marrow changes before X-rays change, show the size and location of the necrotic area, and is central to modern staging systems such as ARCO.

19. Computed tomography (CT) scan of the hip (Imaging test)
    CT uses X-rays to create detailed cross-sectional images of bone. It is especially good for visualizing subchondral fractures and the exact shape of the femoral head when planning surgery in advanced stages.

20. Radionuclide bone scan (bone scintigraphy) (Imaging test)
    A small amount of radioactive tracer is injected, and a camera records how bone takes it up. Areas with reduced or altered uptake can show AVN in earlier stages, though MRI has largely replaced bone scan in many centers.

Non-pharmacological treatments (therapies and other options)

1. Reduced weight-bearing and activity modification
Your doctor may ask you to use crutches, a walker, or a cane and to avoid running, jumping, or heavy lifting. This lowers the load on the damaged femoral head and may slow bone collapse in early AVN. The idea is to give the bone time to repair and remodel itself while reducing pain from mechanical stress. [1][2]

2. Structured physical therapy for hip mobility
Gentle, guided stretching and range-of-motion exercises help keep the hip moving. A physiotherapist teaches safe movements that do not overload the joint but prevent stiffness and muscle shortening. This can reduce pain, improve walking pattern, and delay secondary osteoarthritis. The therapist monitors pain and changes the program as AVN progresses. [2]

3. Hip and core muscle-strengthening training
Strengthening the hip abductors, extensors, and core muscles helps the body hold the pelvis steady while walking. Strong muscles share some of the load so the damaged bone is less stressed. Exercises are usually low-impact, such as bridges, side-lying leg raises, and core stability moves under supervision. [2][3]

4. Weight management and healthy body mass
Carrying extra body weight increases the force passing through the hip in every step. Losing even a small amount of weight can lower joint load and pain. A balanced, calorie-controlled diet plus safe exercise supports gradual weight loss and improves overall bone and heart health at the same time. [3]

5. Smoking and alcohol reduction counseling
Smoking damages blood vessels and alcohol in high amounts is a strong risk factor for AVN. Stopping smoking and reducing or avoiding alcohol can improve blood flow to bone and may reduce progression risk. Counseling, support groups, and medicines to help stop smoking can be part of the plan. [1]

6. Treatment of underlying diseases (steroids, clotting, autoimmune)
Doctors try to lower steroid doses, switch to steroid-sparing drugs, or treat clotting disorders and autoimmune diseases more safely. Better control of sickle cell disease, lupus, or other conditions can reduce repeated vascular damage in the femoral head. This is medical disease management but is still a non-surgical way to slow AVN. [1][2]

7. Assistive devices, canes, and shoe modifications
A cane in the opposite hand, a walker, or crutches can off-load the affected hip. Shoe inserts or small lifts can correct leg length differences or change load distribution. These simple tools often reduce limping and pain during daily activities and help prevent falls. [2][3]

8. Pain self-management education and pacing
Learning how to plan the day, break tasks into smaller parts, and rest before pain becomes severe helps people stay active without overloading the hip. Simple rules like “little but often,” avoiding long standing, and using chairs with arms can make daily life easier. Education keeps expectations realistic and reduces fear of movement. [3]

9. Heat and cold therapy
Warm packs can relax tight muscles around the hip, while cold packs can numb sharp pain after activity. People are taught to protect the skin with cloth, limit each session to about 15–20 minutes, and never sleep with heat on. This is a simple, low-risk way to manage day-to-day discomfort. [3]

10. Hydrotherapy and pool-based exercise
Exercising in water supports body weight and reduces joint load. Walking, gentle kicks, and leg lifts in chest-deep water can improve strength and mobility with less pain. Hydrotherapy is especially helpful for people who cannot tolerate land exercises because of severe hip pain. [2][3]

11. Shock-absorbing footwear and orthotics
Shoes with soft soles and shock-absorbing insoles reduce impact when the heel hits the ground. Custom orthotics may help align the leg and spread forces more evenly across the hip. This can modestly reduce pain during walking and daily standing tasks. [3]

12. Occupational therapy and workplace modification
An occupational therapist helps adapt the home and workplace to reduce hip strain. They may suggest raised chairs or toilets, grab bars, long-handled tools, and techniques to avoid deep squatting or kneeling. These changes protect the hip and support independence. [3]

13. Psychological support and chronic pain coping strategies
Living with long-term pain can cause anxiety, sadness, and sleep problems. Counseling, cognitive–behavioral therapy, and relaxation training help people cope better with pain, stick to treatment, and stay engaged in life. Good mental health supports better physical outcomes. [3]

14. Nutritional counseling for bone and vascular health
A dietitian can design a meal plan rich in calcium, vitamin D, protein, and colorful fruits and vegetables. This supports bone quality and reduces inflammation and cardiovascular risk factors like high cholesterol. Food changes also support weight control, which protects the hip. [3][4]

15. Pulsed electromagnetic field (PEMF) therapy
PEMF devices deliver low-energy electromagnetic waves to the hip. Some studies in osteonecrosis and delayed bone healing suggest that PEMF may stimulate bone cell activity and improve blood flow, which could slow progression in early AVN stages, though evidence is still limited and mixed. [4]

16. Extracorporeal shock wave therapy (ESWT)
ESWT uses focused sound waves delivered from outside the body to the affected hip region. Research in osteonecrosis of the femoral head shows that ESWT may reduce pain and improve function, possibly by stimulating new blood vessel growth and bone turnover, especially when combined with other therapies. [4][5]

17. Hyperbaric oxygen therapy
In hyperbaric oxygen therapy, the patient breathes 100% oxygen in a pressurized chamber. This greatly increases the amount of oxygen dissolved in the blood, which may improve oxygen delivery to damaged bone and support healing in early AVN. Studies in ONFH show pain relief and radiologic improvement in some patients, but access and cost can limit use.[5]

18. Platelet-rich plasma (PRP) as an adjunct to joint-saving procedures
PRP is made from the patient’s own blood and contains concentrated platelets and growth factors. When combined with core decompression, PRP may help bone regeneration and pain relief by stimulating angiogenesis (new blood vessel growth) and bone cell activity. Evidence suggests better pain and function outcomes compared with core decompression alone, but larger trials are still needed. [5]

19. Low-impact aerobic exercise program
Activities such as stationary cycling, gentle walking on flat ground, and elliptical machines can keep the heart and lungs strong without extreme hip loads. A tailored program maintains overall fitness and prevents muscle loss, which is important if surgery is later needed. Intensity is adjusted to keep pain at a tolerable level. [3]

20. Fall-prevention and home safety training
Because the hip is fragile, a fall can cause fracture or worsen collapse. Teaching people to remove loose rugs, improve lighting, use handrails, and practice balance exercises reduces fall risk. Simple safety changes protect both the damaged hip and the rest of the skeleton. [3][4]

Drug treatments

Important: Drug names, doses, and times below are general educational examples based mainly on FDA labels and published studies, not personal medical advice. Only a qualified doctor who knows the patient can choose the right drug and dose.[6][7]

1. Ibuprofen (NSAID pain reliever)
Ibuprofen is a non-steroidal anti-inflammatory drug (NSAID) that blocks COX enzymes and lowers prostaglandins, which cause pain and inflammation.[6] Typical adult doses for arthritis pain are 400–800 mg three or four times daily with food, at the lowest effective dose for the shortest time. It eases hip pain so patients can move and exercise. Main risks include stomach irritation or bleeding, kidney strain, and higher blood pressure. [1][6]

2. Naproxen (long-acting NSAID)
Naproxen is another NSAID used for long-lasting pain relief in hip AVN. It has a longer half-life, so doses such as 250–500 mg twice daily are often enough for steady relief.[6] It reduces swelling and stiffness but shares class risks: stomach ulcers, bleeding, kidney effects, and cardiovascular events, especially at high doses or long-term. Doctors often combine it with stomach-protecting strategies. [2][6]

3. Celecoxib (COX-2 selective NSAID)
Celecoxib is a COX-2–selective NSAID that aims to reduce joint pain and inflammation with a lower risk of stomach ulcers than some older NSAIDs.[7] For osteoarthritis, usual doses are about 100–200 mg once or twice daily. It can help AVN-related pain so that patients can tolerate physiotherapy. Side effects can include heart attack, stroke, fluid retention, and rare skin reactions, so cardiovascular risk must be considered. [2][7]

4. Acetaminophen (paracetamol)
Acetaminophen reduces pain and fever but is not anti-inflammatory. It is often used as a first-line or background pain reliever, for example 500–1,000 mg every 6 hours up to a maximum daily dose according to local guidelines. It can be combined with or used instead of NSAIDs in people with stomach or kidney problems. High doses or alcohol use can damage the liver, so limits are important. [3]

5. Topical diclofenac gel
Diclofenac gel is an NSAID applied on the skin around the hip region. It delivers anti-inflammatory medicine locally with lower blood levels than tablets. This may give mild to moderate pain relief with less risk of stomach bleeding. People apply a measured amount several times daily to intact skin, avoiding broken areas. Skin irritation and rare systemic NSAID effects can still occur. [3][6]

6. Tramadol (weak opioid and SNRI-like analgesic)
Tramadol is a centrally acting pain medicine that weakly stimulates opioid receptors and blocks reuptake of serotonin and norepinephrine. It may be used for short periods in moderate to severe AVN pain when NSAIDs are not enough. Typical oral doses are 50–100 mg every 4–6 hours, up to a daily maximum, under close medical supervision. Side effects include nausea, dizziness, drowsiness, constipation, and risk of dependence and withdrawal. [3]

7. Alendronate (oral bisphosphonate)
Alendronate is a bisphosphonate that binds strongly to bone and inhibits osteoclasts, slowing bone resorption.[8] In AVN, it is sometimes used off-label to support the weakened femoral head and may reduce pain and collapse in early stages. Standard osteoporosis dosing is 70 mg once weekly on an empty stomach with water, staying upright afterward. Side effects include heartburn, esophageal irritation, rare jaw bone problems, and atypical femur fractures with long-term use. [4][8]

8. Zoledronic acid (IV bisphosphonate)
Zoledronic acid is an intravenous bisphosphonate that very strongly blocks bone resorption.[8] It is given as a slow drip, often once yearly for osteoporosis in standard practice. In AVN, it may be used off-label in some bone-preserving protocols, especially when oral drugs are not suitable. It can cause flu-like symptoms after infusion, low calcium, kidney impairment, and rare jaw osteonecrosis, so kidney function and calcium levels must be checked. [4][8]

9. Calcium and vitamin D combination drugs
Fixed-dose tablets combining calcium salts and vitamin D3 help ensure enough raw material and hormonal support for bone mineralization.[9] Typical adult doses might supply around 1,000–1,200 mg elemental calcium and 600–800 IU vitamin D daily, adjusted for diet. They do not cure AVN but support overall bone strength, especially when bisphosphonates or other bone drugs are used. Too much calcium or vitamin D can cause kidney stones or hypercalcemia. [4][9]

10. Enoxaparin (low-molecular-weight heparin)
Enoxaparin is an injectable anticoagulant that helps prevent blood clots by enhancing antithrombin activity. In AVN linked to clotting disorders or after surgery, it can improve venous flow and reduce thrombotic events. Typical prophylactic doses are once or twice daily subcutaneous injections based on weight and kidney function. Main risks are bleeding, bruising, and rare heparin-induced thrombocytopenia. [1][4]

11. Apixaban or similar DOACs (direct oral anticoagulants)
Direct oral anticoagulants like apixaban thin the blood by directly blocking clotting factors (such as factor Xa). They may be used when AVN is associated with deep vein thrombosis, atrial fibrillation, or other clotting problems. Doses are usually taken twice daily, adjusted for kidney function and indication. They do not treat AVN directly but help manage the vascular risk environment. Bleeding is the main side effect. [1]

12. Atorvastatin (statin for lipid and endothelial health)
Atorvastatin lowers LDL cholesterol and improves endothelial function by inhibiting HMG-CoA reductase. Some studies suggest statins may reduce steroid-related AVN risk by improving micro-circulation and lowering fat emboli, though evidence is not conclusive.[1] Usual daily doses are 10–80 mg. Side effects mainly include muscle aches, rare muscle breakdown, and mild liver enzyme elevations, so blood tests are needed. [4]

13. Pentoxifylline (hemorheologic agent)
Pentoxifylline makes red blood cells more flexible and reduces blood viscosity. In AVN, it is sometimes combined with other drugs to improve micro-circulation in the femoral head. Doses are usually 400 mg two or three times daily with food. Side effects include stomach upset, dizziness, and rare bleeding problems, especially when combined with other blood thinners. [1]

14. Cilostazol (antiplatelet vasodilator)
Cilostazol inhibits phosphodiesterase-3 and increases cAMP in platelets and blood vessel walls, causing less clotting and more vasodilation. It is mainly used for leg artery disease but may be considered off-label for some AVN patients with vascular problems. Typical doses are 100 mg twice daily. Common side effects are headache, palpitations, and diarrhea; it is avoided in certain heart diseases. [1]

15. Proton-pump inhibitors (e.g., omeprazole) for stomach protection
When long-term NSAIDs are necessary for hip pain, PPIs help reduce stomach acid and lower ulcer risk. Omeprazole doses are commonly 20–40 mg once daily. These drugs do not treat AVN but protect the digestive tract so pain management remains safer. Long-term use can slightly increase infection and fracture risk, so doctors aim for the lowest effective duration. [6][7]

16. Short-term oral corticosteroid taper for autoimmune flares (very cautious use)
Sometimes, a short course of steroids is required to control severe autoimmune flares that might otherwise worsen overall health. In AVN, doctors try to use the lowest possible dose and shortest course because steroids are a major cause of AVN. They may also add bone-protective drugs at the same time. Side effects include weight gain, mood changes, high blood sugar, and further AVN risk, so decisions are individualized. [1]

17. Disease-modifying drugs for underlying conditions (e.g., hydroxychloroquine)
For AVN driven by lupus or other autoimmune diseases, medicines like hydroxychloroquine or methotrexate control immune overactivity. Better disease control allows steroid doses to be reduced, which indirectly lowers further AVN damage. Doses and monitoring depend on the condition. Possible side effects include eye changes (with hydroxychloroquine) and liver or blood problems (with methotrexate), so regular checks are needed. [1]

18. Bisphosphonate alternatives (e.g., risedronate)
Risedronate is another oral bisphosphonate that slows bone breakdown in osteoporosis similar to alendronate. In AVN, it may be used off-label for bone support when alendronate is not tolerated. Weekly dosing is common. Side effects, precautions, and long-term risks are similar to other bisphosphonates, including stomach irritation and rare jaw bone problems. [4][8]

19. Short-term muscle relaxants (e.g., cyclobenzaprine)
When hip AVN causes muscle spasm in the lower back or thigh, a brief course of muscle relaxant can improve comfort and sleep. Cyclobenzaprine is usually taken at bedtime because it can cause drowsiness. These drugs do not affect the bone but help manage secondary muscle pain. Side effects include dry mouth, dizziness, and sleepiness, so driving and machinery use must be avoided. [3]

20. Local anesthetic injections (diagnostic and short-term relief)
In some cases, doctors inject a local anesthetic, sometimes combined with steroid, into the hip joint to confirm that pain is coming from the hip and to give short-term relief. This is mainly a diagnostic and temporary pain-control tool; repeated steroid injections are used cautiously in AVN. Potential complications include infection, bleeding, and temporary increase in pain. [2]

Dietary molecular supplements

Doses are typical adult ranges; people must always discuss supplements with a doctor or dietitian, especially if they take other medicines or have kidney, liver, or bleeding problems.[4][9]

1. Calcium supplements
Calcium is the main mineral in bone. When diet is low, supplements (often 500–600 mg elemental calcium once or twice daily) help reach a total of about 1,000–1,200 mg per day. This supports bone density around the weakened femoral head. Taken with meals, calcium reduces bone resorption but high doses can cause constipation, kidney stones, or interact with some drugs. [4][9]

2. Vitamin D3 (cholecalciferol)
Vitamin D3 helps the gut absorb calcium and supports bone and muscle function. Many adults use 800–2,000 IU daily, adjusted by blood levels. In AVN, correcting deficiency is important for overall bone quality, even though vitamin D alone does not cure AVN.[10] Too much can cause high calcium, nausea, and kidney problems, so levels should be monitored. [4][10]

3. Vitamin K2 (menaquinone)
Vitamin K2 activates proteins such as osteocalcin, which help bind calcium into bone rather than soft tissues.[11] Supplements (often 90–200 mcg/day for MK-7 in many products) may improve bone quality and reduce fracture risk in some studies. Vitamin K2 may work best when combined with vitamin D3 and calcium. It can interfere with warfarin and other vitamin K-sensitive blood thinners, so medical supervision is essential. [5][11]

4. Omega-3 fatty acids (fish oil, EPA/DHA)
Omega-3 fats have anti-inflammatory effects and may support bone metabolism.[12] Typical doses in supplements range from 500–1,000 mg combined EPA/DHA daily. Some research suggests omega-3 intake is linked with slightly better bone mineral density, but large trials show mixed fracture results.[12] Omega-3s can also support heart health, but high doses may increase bleeding risk in some people. [5][12]

5. Collagen peptides
Collagen peptides provide building blocks (amino acids) for cartilage and bone matrix. Daily doses are often 5–10 g taken as powder in water. They may support joint comfort and bone micro-architecture over time, especially when combined with vitamin C and protein. Side effects are usually mild, such as stomach upset. Collagen does not regrow dead bone but may help overall joint health. [5]

6. Curcumin (from turmeric)
Curcumin is a plant compound with anti-inflammatory and antioxidant properties. Doses in studies often range from 500–1,000 mg/day of standardized extract with enhanced absorption. In osteoarthritis, curcumin can reduce pain and inflammatory markers, sometimes with fewer side effects than NSAIDs.[13] It may help reduce hip pain and systemic inflammation, but can interact with blood thinners and cause digestive upset in some people. [5][13]

7. Vitamin C and E (antioxidants)
Vitamins C and E help protect cells, including bone and blood vessels, from oxidative stress. Vitamin C also supports collagen formation. Typical supplemental doses are around 200–500 mg/day vitamin C and 100–200 IU/day vitamin E, considering dietary intake. Balanced antioxidant intake may support bone and vascular health but very high doses are not advised without medical guidance. [5]

8. Magnesium
Magnesium participates in bone mineralization and vitamin D activation. Supplements of 200–400 mg/day may help if diet is low. Adequate magnesium supports muscle and nerve function, which helps with balance and fall prevention. Too much can cause diarrhea or, in kidney disease, dangerous high blood levels, so dosing should be cautious. [5]

9. Zinc
Zinc is important for bone and tissue repair. Low to moderate doses (for example 10–15 mg/day) may be used when deficiency is suspected. It supports enzyme activity in bone formation and immune function. High doses over long periods can cause nausea, interfere with copper, and weaken immunity, so more is not always better. [5]

10. L-arginine or L-citrulline
These amino acids are precursors for nitric oxide, a molecule that widens blood vessels. Supplements (often 2–6 g/day split doses) may improve micro-circulation, potentially supporting blood flow around the femoral head, though AVN-specific data are limited. Side effects can include stomach upset and low blood pressure, especially if combined with blood-pressure medicines. [5]

Regenerative, immunity-supporting, and stem-cell-related drugs

1. Teriparatide (PTH 1-34, bone-forming hormone analog)
Teriparatide is a recombinant parathyroid hormone fragment that stimulates bone-forming cells (osteoblasts) when given in small daily injections.[14] It is approved for severe osteoporosis and can improve bone quality and reduce fractures. In AVN, it is being studied off-label as a way to support bone repair around the necrotic zone. Typical treatment is 20 mcg once daily for up to 2 years. Side effects include nausea, leg cramps, and transient high calcium. [4][14]

2. Denosumab (RANKL inhibitor biologic)
Denosumab is a monoclonal antibody that binds RANKL, stopping osteoclast formation and strongly reducing bone resorption.[15] It is given as a subcutaneous injection every 6 months for osteoporosis. In AVN, it may be used off-label in selected patients to stabilize bone around the femoral head, but evidence is still emerging. Side effects include low calcium, jaw osteonecrosis, and rebound bone loss if stopped suddenly without another bone drug. [4][15]

3. Romosozumab (sclerostin-blocking antibody)
Romosozumab blocks sclerostin, a protein that slows bone formation, leading to rapid increases in bone mass.[16] It is approved for high-risk osteoporosis and given monthly for 12 months. In theory, it might help rebuild bone in or near AVN lesions, but this is still experimental and must be used carefully because of possible cardiovascular risks in some patients. [4][16]

4. Autologous bone marrow aspirate concentrate (BMAC)
BMAC is made by concentrating a patient’s own bone-marrow cells, which include mesenchymal stem cells, and injecting them into the necrotic area, often combined with core decompression. The aim is to deliver cells and growth factors that can form new bone and blood vessels. Studies show improved pain and hip survival in some early-stage AVN cases, but techniques and long-term results vary. [5]

5. Mesenchymal stem cell (MSC) implantation
MSC therapy uses cultured or concentrated stem cells from bone marrow or fat tissue to seed the necrotic femoral head, sometimes with scaffolds. These cells can differentiate into bone and support blood vessel growth. Early clinical studies report promising hip preservation in young patients, but treatment is still experimental, costly, and not widely available. [5]

6. Platelet-rich plasma (PRP) as a regenerative biological agent
Beyond being a “procedure,” PRP is a concentrated biological drug made from the patient’s platelets. It delivers high levels of growth factors that can support tissue repair. When injected during core decompression, PRP may improve pain, function, and radiologic healing compared with surgery alone. Side effects are usually mild pain or swelling at the injection site, but methods are not standardized. [5]

Surgeries (Procedures and why they are done)

1. Core decompression
In core decompression, the surgeon drills one or more channels through the neck of the femur into the necrotic area. This lowers pressure inside the bone, improves blood flow, and creates tunnels where new blood vessels and bone can grow. It is usually done in early stages before collapse, often as day surgery, to relieve pain and delay or prevent joint destruction. [2][5]

2. Core decompression with bone graft or biologic augmentation
Here, after drilling, the surgeon fills the tunnel with bone graft (from the patient or a donor) and sometimes BMAC or PRP. The graft acts like a scaffold to support the weak femoral head and provide cells and growth factors. This combination may give better structural support and faster healing than drilling alone, especially in larger lesions. [5]

3. Vascularized bone graft (e.g., fibular graft)
In this more complex surgery, a piece of bone with its own blood vessel (often from the fibula in the leg) is transplanted into the femoral head. The graft brings a new blood supply and strong structural support. It is used mainly in younger patients with advanced but not fully destroyed hips. The operation is long and technically demanding but can preserve the native hip for many years. [2]

4. Proximal femoral osteotomy
An osteotomy reshapes and reorients the upper femur so that a healthier part of the femoral head carries most of the body weight. By turning the damaged area away from the main load zone, pain can improve and collapse may progress more slowly. This option is considered in selected younger patients with localized lesions and good remaining bone. [2]

5. Total hip arthroplasty (total hip replacement)
When the femoral head has collapsed and cartilage is badly damaged, total hip replacement is the most reliable way to relieve pain and restore function. The surgeon removes the damaged femoral head and acetabular cartilage and replaces them with artificial components. Modern implants can last many years, but in younger people, there is a chance that revision surgery will be needed later in life. [2]

Preventions

1. Avoid unnecessary high-dose or long-term steroids – Use the lowest effective dose and shortest duration, and ask about steroid-sparing options. [1]

2. Limit or avoid heavy alcohol use – High daily alcohol intake is a strong AVN risk factor; cutting down can reduce future damage. [1]

3. Protect hips from major trauma – Use seatbelts, safe sports techniques, and appropriate protective gear to avoid hip dislocation or fractures.

4. Manage lipid and cholesterol levels – Treat high cholesterol and triglycerides to lower fat emboli risk in the tiny hip vessels.[1]

5. Treat clotting disorders early – Work with specialists if you have thrombophilia or recurrent clots so blood flow to the bone remains good.

6. Stop smoking – Smoking narrows blood vessels and reduces oxygen delivery to the femoral head; quitting improves circulation.

7. Maintain a healthy body weight – Avoid both obesity and severe underweight, as both harm bone and joint health. [4]

8. Stay physically active with low-impact exercise – Regular walking, cycling, or swimming supports bone and muscle without overloading joints.

9. Monitor high-risk patients – People on long-term steroids, with sickle cell disease, HIV, transplant, or lupus should have early evaluation if hip pain appears. [1][2]

10. Regular bone health checks – DEXA scans, blood tests for vitamin D and calcium, and medication reviews help detect problems early.

Each of these steps cannot fully prevent AVN, but together they can significantly lower risk and slow damage. [1][4]

When to see doctors

You should see a doctor as soon as possible if you have deep groin, buttock, or thigh pain on one or both sides that worsens when you stand or walk, especially if you use steroids, drink a lot of alcohol, or have sickle cell or autoimmune disease. [1][2] Sudden inability to bear weight, a new limp, or loss of hip motion are warning signs that need urgent assessment. After a hip injury, any pain that does not settle within a few days also needs medical review. Early MRI and specialist referral can greatly improve the chance of saving the joint. [2][5]

What to eat and what to avoid

1. Eat calcium-rich foods – milk, yogurt, cheese, tofu with calcium, and leafy greens support bone strength. [4][9]

2. Include vitamin D sources – fatty fish, egg yolks, fortified foods, and sensible sun exposure help maintain vitamin D.

3. Choose lean protein – fish, poultry, beans, lentils, and low-fat dairy provide building blocks for bone and muscle.

4. Add colorful fruits and vegetables – berries, citrus, peppers, and leafy greens supply antioxidants that may reduce inflammation.

5. Use healthy fats – nuts, seeds, olive oil, and omega-3-rich fish support heart and bone health. [5][12]

6. Avoid or limit alcohol – high alcohol intake is strongly linked to AVN and weak bones; if you drink, keep it low and occasional. [1]

7. Cut down on sugary drinks and ultra-processed snacks – these add calories without nutrients and may worsen weight and inflammation.

8. Reduce very salty and fast foods – too much salt can increase calcium loss in urine and raise blood pressure.

9. Limit trans fats and deep-fried foods – they worsen vascular health, which is crucial for bone blood supply.

10. Avoid extreme crash diets – rapid weight loss can harm bone and muscle; aim for slow, balanced loss if needed. [4]

Frequently asked questions

1. Can avascular necrosis of the femoral head heal on its own?
In very early stages and small lesions, some healing may occur if blood flow improves and the bone is protected, especially with weight-bearing restriction and bone-supporting drugs. However, many cases progress, so regular monitoring and early treatment are important. [1][2]

2. Is AVN always caused by steroids or alcohol?
No. Steroids and heavy alcohol are common causes, but AVN can also follow hip injuries, sickle cell disease, clotting disorders, decompression sickness, and some autoimmune or metabolic diseases. In some people, no clear cause is found (idiopathic AVN). [1]

3. How is AVN of the femoral head diagnosed?
Doctors start with a history, physical exam, and X-rays. In early disease, X-rays can be normal, so MRI is the best test to detect early bone death and assess lesion size and stage. Sometimes CT scans or bone scans are used for detail. [2]

4. What happens if AVN is not treated?
Without treatment, the necrotic bone is likely to weaken and collapse. The femoral head becomes irregular, the cartilage wears down, and painful hip osteoarthritis develops. Eventually, walking becomes very painful and a total hip replacement is usually needed. [2][5]

5. Can exercise make AVN worse?
High-impact activities like running or jumping can speed up collapse and should be avoided. However, carefully chosen low-impact exercises and physiotherapy can protect muscles and joint function and are usually helpful. The key is to follow a plan made with your care team. [2][3]

6. Are bisphosphonates safe for AVN?
Bisphosphonates like alendronate and zoledronic acid are widely used in osteoporosis and have been tried in AVN to slow bone collapse.[4][8] They can help some patients but need careful dental, kidney, and calcium monitoring because of rare side effects such as jaw osteonecrosis and atypical femur fractures. [4][8]

7. Do supplements like vitamin D and K2 really help?
Vitamin D and K2 help the body handle calcium correctly and support bone quality.[9][11] They are most helpful if you are deficient or at high fracture risk. They do not “cure” AVN but can be an important part of an overall bone-health plan along with diet, exercise, and medical treatment. [4][9][11]

8. Are stem cell treatments for AVN proven?
Stem cell and BMAC therapies are promising in early studies, especially when combined with core decompression, with improved pain and hip survival in some series.[5] However, techniques vary, long-term safety and effectiveness are still being studied, and they are not yet standard everywhere. [5]

9. When is hip replacement my best option?
Total hip replacement is generally recommended when the femoral head has collapsed, the joint space is lost, and pain and disability remain despite non-surgical treatments. At this stage, hip-preserving surgeries are usually less successful, and replacement offers the best chance for strong pain relief and function. [2]

10. How long does a hip replacement last in someone with AVN?
Modern implants can often last 15–20 years or more, but younger or very active patients may need revision surgery in the future. Good weight control, muscle strengthening, and avoiding extreme activities help implants last longer. [2][5]

11. Is AVN common in young people?
Yes, AVN can occur in teenagers and young adults, especially after trauma, high-dose steroids, or in sickle cell disease and other blood or autoimmune conditions. Because younger patients want to avoid early hip replacement, early diagnosis and hip-preserving strategies are particularly important in this group. [1][2]

12. Can changing my diet stop AVN?
Diet alone cannot stop AVN because the main problem is blood supply inside the bone. However, a bone-healthy diet supports overall bone strength, helps with weight control, and can improve heart and vessel health, which indirectly supports treatment. [4][5]

13. How quickly does AVN progress?
Progression speed varies. Some small, early lesions stay stable for years, while others collapse within one or two years. Progression depends on lesion size, location, cause, and risk factors. Regular follow-up with imaging helps doctors time interventions correctly. [1][2]

14. Can I still work if I have AVN of the femoral head?
Many people continue working, especially in jobs where heavy lifting, prolonged standing, or repetitive squatting are not required. Occupational therapy and workplace adjustments can make work safer. In physically demanding jobs, modifications or temporary changes may be needed during treatment. [3]

15. What is the main goal of AVN treatment?
The main goals are to relieve pain, maintain or restore hip function, slow or prevent collapse of the femoral head, and delay or avoid hip replacement when possible, especially in younger patients. A personalized mix of lifestyle measures, drugs, and possibly surgery is used to reach these goals. [2][5]

Disclaimer: Each person’s journey is unique, treatment plan, life style, food habit, hormonal condition, immune system, chronic disease condition, geological location, weather and previous medical  history is also unique. So always seek the best advice from a qualified medical professional or health care provider before trying any treatments to ensure to find out the best plan for you. This guide is for general information and educational purposes only. Regular check-ups and awareness can help to manage and prevent complications associated with these diseases conditions. If you or someone are suffering from this disease condition bookmark this website or share with someone who might find it useful! Boost your knowledge and stay ahead in your health journey. We always try to ensure that the content is regularly updated to reflect the latest medical research and treatment options. Thank you for giving your valuable time to read the article.

The article is written by Team RxHarun and reviewed by the Rx Editorial Board Members

Last Updated: February 09, 2025.