SC and Avascular Necrosis


This series will focus on breaking down and understanding each of the complications that might develop from sickle cell, so that you can know how to prevent it, and how to catch it early.

What is Avascular Necrosis?

Avascular Necrosis (AVN), government name osteonecrosis, is defined as death of the bone due to reduced or limited blood supply to the bone tissue. The necrosis (or death), leads to a thick scar tissue developing, which then prohibits any further healing of the bone, leading to joint pain and loss of function.

The joints most often affected by AVN (in decreasing order of incidence) are the hip, knee, shoulder, ankle/foot (talus), wrist and elbow. This is because these sites are more prone to have less collateral (smaller veins) that can provide circulation to the affected area, and usually only have a single large blood vessel that delivers circulation. Sickled cells find it quite easy to clump up this one blood vessel, and the risk for AVN is developed.

Risk Factors: AVN occurs in individuals of all ethnicities; although those with sickle cell diseases are more prone to this complication. It is more common in men than women (ratio of 8:1), and develops most often in middle age. With SCD, patients develop AVN from age 12, and once you have developed it, there is an increased chance for getting AVN in the future. Alcohol use puts you at risk for AVN.  Also, patients who are on dialysis, have lupus, or who routinely use steroids (like in the treatment of acute chest syndrome, and pulmonary hypertension, are at an increased risk of getting AVN). More than 50% of patients diagnosed with AVN require surgery 3 years after.

What Causes AVN in Sickle Cell?: When in crises, sickled cells float around clumping up in various parts of the body. This leads to tissue starvation and pain. The bone is a living structure, and requires blood circulation to provide oxygen and energy to all the cells. The arteries and veins are responsible for providing this nutrition. In the bone structure, there is usually only one vein and one artery that delivers blood to a certain area, and once this is clogged up by sickled cells, there are no alternate routes. This leads to death of the bone. Osteoblasts and osteocytes come in to curtail the spread of infection, and a thick scar tissue is developed on the blackened, dead area. This means that no healing or repair can be done once the sickle cells leave and circulation is restored. As a result, that part of affected bone is PERMANENTLY dead, and is unable to function normally.

How do you know if you have AVN? The main sign of AVN is pain in the bone that is there regardless of whether or not you are in crises. Usually this pain is in the joint between the hip and thigh bone, and can be felt when walking. There might be tenderness in other surrounding areas. You might find yourself unable to have a normal range of motion in the affected side. You might find yourself unable to bend over and tie your shoes. In some people, AVN is so advanced that you might have a slight limp or clicking in movement. In addition, if the bone compresses the nerve, there might be some numbness, tingling or lack of sensation in the affected extremity.

AVN of the hip sometimes shows up on an X-ray as a blackened area. However, unless your doctor suspects AVN he won’t routinely order this X-ray for you. You have to ask for it.  In other parts of the body, the AVN might be so microscopic that it won’t show up on an X-Ray. CT scans or Bone scans are also used, but are not sensitive enough tests. This is why it’s important to ask for an MRI of the affected area. Although MRIs are expensive and there is an increased risk of radiation, they are the most effective with diagnosing AVN.

How do you treat it? There are 7 stages of AVN and the treatment plan is based on what stage of AVN you are in, whether it is symptomatic, and the severity of symptoms.

Joint/Hip Replacement: Since AVN affects the joints or hip, the dead section is completely removed and a metallic joint is placed in that works just like the dead bone should. Doctors tend not to be aggressive in suggesting Joint Replacement until AVN is in its advanced stages. This is because once you have a hip or joint replacement, you have to have another surgery every 10 years to replace the hardware. And you know every time you go under the knife, there is a risk of complications like infection and hardware rejection.

Core Decompression: The orthopedic surgeon will drill a hole into the affected bone that takes a chunk of the dead necrotic area out. This leads to less pressure on the bone. The thought is that this will then allow the bone to regenerate on its own, since the scar tissue has been removed and blood circulation has been restored. This often works in intermediate stages, promotes healing and provides relief from the pain. It is 35-95% successful in treating AVN patients, especially those in pre-collapse.

Osteotomy: This procedure involves rotating one of the joints, so that the joint is no longer resting on a dead, painful area. It is not as effective as core decompression, and as a result is rarely suggested.

Bone Graft: This involves melding a new piece of bone gleaned from a healthier part of the body, and grafting it unto the dead area, thereby promoting circulation and healing.  Bone graft is often done with core decompression and in small areas, is about 70-91% effective in mild to moderate AVN. This option is great because there is a possibility for complete bone healing, especially in the femoral head. In addition, there is a reduced risk of infection from hardware placed during joint replacement. However, the recovery time is longer than with joint replacement and there is less complete pain relief.

Pain Management: In mild AVN, the conservative treatment is pain management through NSAIDs like Motrin, Aleve or other pain-killers and analgesics. If the pain is under control, then you can engage in flexibility and joint exercises which might help to promote circulation to the bone.

Alternative Remedies: To prevent and treat AVN at home, it is recommended to:

  • Engage in activities and increase circulation in the bone like low impact exercises, walking, yoga, swimming
  • Take supplements that promote bone growth like calcium, vitamin D, and carao
Reference: Toffieri, J.K. & Gilliland, W. Avascular Necrosis: eMedicine Rheumatology. Published December 19, 2009.


  1. Good job on informing people! Unfortunately I was diagnosed with AVN at the age of 18 and by the time we caught it the disease had progressed to the point where a hip replacement was my only option. It was a very tough time for myself and my family especially. My surgery was during the middle of senior year of high school….a time that was supposed to be fun and exciting. Unfortunately I spent much of it in the hospital or at home recovering and getting physical therapy. I missed prom my senior trip, and a slew of other senior year activities. I’m doing a lot better now–physically and emotionally–I’ve finally come to accept my new hip and I’m more tolerant of the scar that the surgery left (before I couldn’t even glance at the right side of my body).

  2. Hi everyone, I was diagnosed with AVN in 2008. Doctors said I wouldn’t be able to walk in 2 years time and its been 6 years now and I’m still walking. My hip has been totally collapsed, I haven’t done any surgery but the power of God is keeping me. I’m 20 years old and God has my sickle cell under control.

  3. Hi everyone, just joining this awesome website. I was diagnosed with AVN in 2008 and doctors said in 2 years time I wouldn’t be able to walk. It has been six years now and I’m still walking despite the fact that my left hip has totally collapsed and I have not done an hip replacement. I am 20 years old, I’m a christian and believe so much in God because he has been keeping me healthy, keeping my sickle cell under control. Doctors said I wouldn’t live to see 5 years old but I’m here and I know that I shall live and not die to declare the works of the Lord. There is hope in God friends!

  4. Hello My daughter is 16 years old She has started she has started feeling the pain on both her hip and knee she is the 3rd Stage of AVN and her Doctors are telling me to control it with pain meds and slow down the Hip Replacement and that she is young and other parents are telling me to repalce it am getting confused and worried Please advise
    Desperate Mother

  5. Thanks for all your messages. I’m beginning to feel pain in my hip at 32. And everything I read on the internet has been nothing but scary. Also trusting God for complete healing

  6. Hi everybody, I’m a lady of 34 years and I just started feeling pain in my left hip, especially when I have seated for long and want to stand up, I feel the sharp pain and sometimes when am lying down and want to turn around on my bed I hear a sound from my hip bone.dont know what to do, I don’t want to limp

  7. Hello to All,

    My son is a sickle cell warrior and was recently diagnosed with AVN at the age of 11. Is there a support group that can assist us with this new diagnosis in the broward County area in Florida?

  8. Tanx for all your help am 31 and sometimes I feel a sharp pain in my waist but my problem is my younger sis.she started limping 8yrs ago and she is 20yrs now I want to know what can happen to her if operation is not done?

  9. Pls my daughter is only four and this pain just started at her hip while in crisis. She’s limping. I was told children that young are not likely to suffer AVN. Pls any comment on this

  10. Wow! I was encouraged reading all these. Am 38. My pain started when I was 36. I used walking aids for a year because I could not walk again on my own and no money to proceed for the surgery. I started walking again but I limp without the walking aid and surgery.


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