A-vascular Necrosis (AVN)

Oxygen is essential to the viability of bone cells as well as to healing and rebuilding processes. Due to that- Hyperbaric Oxygen therapy (HBOT) might be suitable in treating patients suffering from AVN. 

What is AVN?

​A-vascular Necrosis, a non infectious necrosis, is a pathology that can occur due to several various illnesses or medical interventions. The pathology involves damage to the blood cells, ischemia and even necrosis if left untreated, which causes structural damage to the bone and a destruction of the joint within 3-5 years. It is wildly presumed that AVN is responsible for 10% of cases where patient ultimately will require a total hip replacement. On average, the symptoms will begin to show under the age of 40.

AVN is divided into four categories of severity:


  • Category 0- all the imaging testing comes back normal and the diagnosis is purely according to the histology.
  • Category 1- X-ray and CT are normal, but the histology and MRI demonstrate the injury.
  • Category 2- Imaging testing shows the injury but there isn’t evidence of a structural interference or collapsing of the joint.
    Category 3- Structural interference exists- flattening of the joint cap or a positive crescent sign.
  • Category 4- Flattening of the head of the joint along with a narrowing of the joint space, as well as other sings of osteoarthritis.

Treatments for AVN

​There are two acceptable treatments for AVN:


  • The conservative approach: bed rest, getting weight off the joint by the use of a crutch, and administering pain killers. Studies show that only 23% of patients treated conservatively saw any kind of significant clinical improvement.
  • The surgical approach: an operation to replace the joint.

HBOT Approach

Oxygen is essential to the viability of bone cells and to healing and rebuilding processes. In addition, HBOT has been known to reduce edema, decrease pressure within the bone, and improve the drainage inside the veins and to have an anti-inflammatory effect. Meaning- patients suffering from AVN can surely benefit from HBOT treatments.


The recommended treatment course is 40 treatments, five days a week, while monitoring the effectiveness of the treatment with clinical checkups and a repeat MRI.


A study conducted at the Rambam Medical Center in Haifa, Israel, by Professor Rise, showed that 81% of the patients who received HBOT had a repeat MRI that was once again normal, compared to a control group where only 17% of patients had a normal repeat MRI. In addition, HBOT is a safe treatment method which does not require any kind of invasive procedures/surgery to the joint or bone, and its effectiveness can simply and effectively be monitored by an MRI.

In conclusion, HBOT can in fact help patients suffering from AVN in cases where there is still no mechanical collapse of the joint or bone (AVN Category 0-2).