What is Avascular Necrosis (AVN)?

Avascular mortification may be a sickness ensuing from the temporary or permanent loss of blood offer to the bone. Without blood, the bone tissue dies which can cause the bone to collapse. If AVN involves the bones close to a joint, it should cause collapse of the joint surface. Although death will occur in any bone, it most frequently affects the ends of long bones. It will have an effect on one joint at a time, 2 or more joints at a similar time or completely different|completely different} joints at different times.

The amount of incapacity that results from avascular mortification depends on many factors:

  • What part of the bone is affected;
  • How big a neighborhood is involved; and
  • How effectively the bone rebuilds itself.

Normally, bone endlessly breaks down and rebuilds—old bone is torn away and reabsorbed, and replaced with new bone. This method keeps the skeleton sturdy and helps it to take care of a balance of minerals.

Within the course of avascular necrosis, however, the bone tissues break down quicker than the body will repair them. If the sickness progresses and therefore the bone collapse, the joint surface might break down and cause pain and inflammatory disease. It’s vital for AVN to be diagnosed and treated as shortly as attainable.

What causes AVN?

AVN from developmental hip abnormalcy (DDH) may be a results of treatment however it doesn’t mean that your doctor did something wrong. The circulation to an infant’s hip is of course weak as a result of the blood  comes in from blood vessels below the hip because the blood supply can’t are available in through the joint surface at the highest of the ball. If the hip is separated, the blood vessels are kinked from the dislocation.

Generally the blood vessels clean up once the hip is force down from the separated position and replace into the articulatio spheroidea. AVN is a lot of common once plenty of force is needed to place the hip back to the joint or once an extreme position of the hip is employed to carry the hip within the joint. Rarely, the blood offer is broken throughout surgery, however the same old cause is just putting the hip back to the joint.

The International Hip abnormalcy Institute (IHDI) is learning the frequency of AVN to examine if there area unit ways in which to seek out a lot of risk factors therefore we are able to find higher ways in which to avoid AVN.

AVN is caused once the blood offer is interrupted and enough blood doesn’t get to the bone. Blood travels to the bone through blood vessels. Enough blood cannot get to the bone if blood vessels get blocked by fat or air, if they become too thick or too thin, or if they get too weak.

Several things will cause this to happen. Some cancers have this impact on blood vessels and bone. a number of your child’s treatments can also have this impact. Corticosteroids (prednisone) in high doses and radiation to a joint are also conducive factors, although we tend to not utterly perceive why. Sadly, it’s not forever attainable to work out specifically what caused the matter.

What are the symptoms of AVN?

In the early stages of AVN, patients might not have any symptoms. Because the illness progresses, most patients experience joint pain— at 1st, putting weight on the affected joint and later even when resting. Pain typically develops bit by bit and will be gentle or severe.

If avascular necrosis progresses and therefore the bone and encompassing joint surface collapse, pain might develop or increase quickly. Pain is also severe enough to limit the patient’s vary of motion within the affected joint. the amount of your time between the primary symptoms and loss of joint perform is totally different for every patient. It ranges from many months to over a year. If your kid has pain within the joints, he or she ought to see the doctor. The sooner AVN is diagnosed, the simpler it’s to treat.

How is AVN diagnosed?

Early stages of AVN might look normal on an X-ray, thus your doctor might want your kid to possess a resonance imaging (MRI) scan, a bone scan, or a computed axial tomography (CT) scan. Early signs of AVN are best seen with an magnetic resonance imaging. Later stages of AVN may be seen with an X-ray.

What happens once AVN occurs?

When an adult hip loses its blood offer, the hip sometimes deteriorates quickly and causes severe inflammatory disease. In kids between the ages of five and twelve years, the condition is termed Legg-Calvé-Perthes illness and therefore the results are variable betting on severity and treatment. Loss of circulation during this 5-12 year age bracket will cause collapse of the ball so it’s flat rather than spherical. Flattening of the ball during this age bracket limits activities and ends up in early inflammatory disease.

AVN in infants and really young kids doesn’t act something like AVN once the age of six years, therefore there is also some confusion after you search AVN on-line and see what happens to adults or slightly older kids. once AVN happens in babies or young kids, the hip stays spherical and eventually recovers its blood offer, however the temporary loss of circulation will injury the expansion plate of the higher finish of the thigh bone. Because the kid grows, the leg on the affected facet is also shorter, or the neck of the thighbone is also short and causes a limp.

A bigger downside that usually goes along side AVN is incomplete reduction of the hip. There’s no have to be compelled to treat the AVN at a young age, however incomplete reductions have to be compelled to be corrected whether or not there’s AVN or not.

How does one know that they have AVN?

AVN is known once treatment with a Pavlik harness, a cast, or surgery once the bone within the ball of the hip fails to seem on x-ray or fails to grow for an amount of 1 year. Once it will begin to seem, it’s completely different from the opposite hip. Tests like MRI, bone scans, or CT scans area unit wont to diagnose AVN in adults of in older kids with Legg-Calvé-Perthes illness, however these tests area unit seldom useful before the age of 5 years.

There’s no have to be compelled to diagnose AVN promptly in babies or young kids as a result of there’s no treatment. The main target of treatment during this age bracket must get on ensuring the hip stays within the socket as a result of the expansion disturbance from AVN takes time to indicate up and longer before treatment.

 this is often a nineteen month old girl who was treated with a Pavlik harness at age three months. She is sixteen months once treatment and therefore the bone that ought to be within the ball of each hips has not appeared, though there’s a faint look of some bone on the proper facet. Each hips are within the sockets and there’s no would like for a lot of treatment at this age. Eventually, she may have surgery if the form of the higher thigh becomes abnormal with growth. Compare this to the hips of the kid below.

This is a nineteen month previous boy who was treated with a Pavlik harness at the age of eight months. You’ll see that each hips have fashioned usually and therefore the bone within the ball of every hip is massive and spherical. This boy failed to develop AVN.

What are the treatment options for AVN?

Several treatments are offered that facilitate stop more bone and joint harm and facilitate to alleviate pain. To work out the foremost applicable treatment, the doctor considers the following:

  • Age of patient
  • Stage of cancer and in progress cancer treatments
  • Stage of avascular necrosis
  • Location and quantity of bone affected

The goal in treating avascular necrosis is to enhance the patient’s use of the affected joint and limit more harm to the bone.

Physical therapy

Your child’s doctor can in all probability advocate an analysis by a healer, who will show your kid ways in which to maneuver with additional comfort.

Decrease weightbearing

One of the foremost vital belongings you will do to slow the progression of AVN is to limit the number of weight or pressure placed on the joint. If the AVN affects the elbow or shoulder, you’ll have to be compelled to modification the sort of sports or different activities during which your kid takes half. for instance, swimming would be a far better activity than athletics.

Most often AVN affects the hips or knees. The doctor might advocate that your kid use crutches to limit the pressure or weight placed on the bone and joint. This slows harm to the bone and permits natural healing. Once combined with medication to cut back pain, weakened weight bearing may be efficient thanks to avoid or delay surgery.

Range of motion exercises

It is vital that your kid keep all joints versatile. Usually joint stiffness will occur before you even notice. Once AVN is diagnosed, the healer can show you exercises to form positive your kid doesn’t lose his or her vary of motion. If tightness has already occurred, your kid might have to check a healer on an everyday basis for a jiffy to stretch out. Staying versatile can facilitate retain movement in your child’s joints.

Strengthening exercises

The healer can advocate totally different exercises for keeping the muscles around your child’s joints sturdy. The stronger the muscles are, the higher in a position they’re to guard the joint.

Increase circulation

• Exercise can facilitate increase blood circulation to the joint. This promotes healing and conjointly relieves pain.

• Heat within the type of hot packs can also facilitate as a result of it causes additional blood to flow to the heated space. this can be restful and conjointly promotes healing. Your doctor or healer can talk over with you regarding the employment of warmth reception. Generally, heat before exercise makes exercise easier and results in higher movement.

Surgical choices

Core Decompression

Core decompression may be a surgery that removes the inner layer of bone. This might scale back pressure at intervals the bone and build associate degree open space for brand new blood vessels to grow. Generally a bit of healthy bone with sensible blood vessels is place into this space to hurry up the method. This procedure works best within the earliest stages of AVN. this could facilitate to alleviate pain yet as promote healing. When a core decompression, your kid mustn’t place lots of weight thereon bone for many weeks whereas it heals. The medical practitioner can teach your kid the way to use crutches.


An operation may be a surgery that involves eliminating a bit of bone, typically a wedge, to reposition the bone. this permits the avascular space connected less weight than an adjacent healthy space. A drawn-out recovery amount is required when this surgery and activity are restricted for 3-12 months.


Arthroplasty is usually referred to as a joint replacement. The morbid bone is removed and replaced with artificial components. This treatment is also required within the late stages of avascular necrosis and once the joint is destroyed.

  • Avoid activities that place lots of stress on the joints. Activities that stress the joints embody running, jumping, football, soccer, volleyball and different contact sports that “pound” on the joints. If {you are|you’re} undecided that activities or sports are alright to do, raise the expert or doctor. Activities that are sensible for joints with AVN embody swimming and cycling.
  • Be according to the exercises that are suggested.
  • Hear the joints! Rest them after they hurt.
  • Let the doctor or healer understand once symptoms modification.
  • Take pain or medicinal drug medications as prescribed.