Avascular Necrosis means death due to a lack of blood supply to the tissues. According to a reliable source in India, we get about 16,000 new cases of avascular necrosis every year, which sooner or later will require total hip replacement surgery. The average age for patients with avascular necrosis is around 32 yrs. The most common joint affected by avascular necrosis is the hip.
The disease has been known by different names:
- Aseptic necrosis
- Ischemic bone necrosis
- Bone infarction
Avascular Necrosis occurs in bones due to a lack of blood supply followed by the death of tissue whose blood supply has been compromised. The bone will eventually collapse. The effect of Avascular Necrosis may be severe to very severe depending on which bone is involved. Avascular Necrosis may originate in the hip, arm, shoulder, knees, and even ankles.
How Avascular Necrosis does present?
May not produce any symptoms until disease progression starts:
- mild or severe pain of the affected area
- in case of hip, groin pain radiating down to the knee
- pain while or inability to bear weight on that leg
- limitation or loss of movement
- resting pain during a later stage
Causes and Risk Factors for Avascular Necrosis:
As stated above, Avascular Necrosis is attributed to the loss of blood supply to the bone or joint. This may be due to:
- Too much alcohol intake
- Prolonged consumption of corticosteroids
- Legg-calve Perthes disease
- Idiopathic spontaneous avascular necrosis of knee called spunk or sonc
- Decompression sickness and caisson disease (rapid discharge of nitrogen into the blood)
- HIV infection
- Bisphosphates to treat bone cancer
- Exposure to chemotherapy or radiation therapy
- Gaucher’s disease
- Post organ transplant, especially kidney transplant
- Sickle cell anaemia
How is Avascular Necrosis diagnosed?
- Medical History
- Physical Examination
- CT Scan
- Bone Scan – A radioactive substance is injected and scans taken, avascular necrosis of any bone within the body can be diagnosed in just one scan.
- Bone marrow pressure
How is Avascular Necrosis treated?
The treatment method is decided based on:
- Patient age
- Underlying cause
- Which bone is involved
- The extent of damage
- Achieving pain management
- Achieving joint mobility
- Prevent disease progression
Let’s look at the Management plan:
- Medication Management – If the detection is early
- Statins for reducing cholesterol
- Blood thinners
- Physical Therapeutic Management
- Limit weight bearing on the affected leg
- Use of walkers, callipers or crutches for the same
- Passive or active exercises for maintaining range of motion
- Electrotherapy for bone growth enhancement
- Surgical Management – If medically not manageable
- Core Decompression – The procedure is carried out by drilling holes in the area of dead bone near the joint. This process reduces pressure, allows for increased blood flow, and slows or stops bone destruction. This procedure prevents arthritis, bone collapse, and even joint replacement at a later stage.
- Bone Grafting – Another healthy bone with intact blood supply is taken and grafted at the site of bone decompression. Sometimes a synthetic bone graft is used for the purpose. A very good example is Vascularized Fibula graft at the neck of femur avascular necrosis with intact blood supply.
- Osteotomy – Here the necrosis bone is cut, curated, and reestablished after reshaping it at the position with maximum biomechanical advantage.
- Total Hip Replacement – If the damage is extremely severe and the age of the patient is less, this is the choice of treatment to attain total joint mobility and functional independence.
- Avascular necrosis of the jaw is treated with medical management by removing the necrosed part followed by antibiotics and mouthwash.
As the age of onset of the disease is very young even medically managed patients may, in the long run, need surgery. After management, most patients spend an active and independent life with a few cautions and contraindications. Likely, osteoarthritis of the involved joint may eventually develop.
Preventing Avascular Necrosis:
- Limited and supervised consumption of corticosteroids
- Reduce alcohol intake
- Quit smoking
- Keep your weight in check
- Visit your doctor regularly
For Avascular Necrosis of the jaw:
- Brush and floss daily
- Immediate consult on signs of redness or pain
This bit must have added information to your gen base about avascular necrosis. Keep updating!!
Dr. Rajesh Verma, Director & Senior Consultant – Orthopaedics, Spine Surgery, Dharamshila Narayana Superspeciality Hospital, Delhi & Narayana Superspeciality Hospital, Gurugram