Overview
Necrosis means the death of tissue. Avascular necrosis (AVN) is a condition resulting from the death of tissue in the bone. This damage to the bone tissue is due to a lack of proper blood supply. Avascular necrosis can result from an injury or from being more alcoholic or can also be due to the corticosteroid medication to treat some other health problem.
Generally, men are more prone to get AVN than women. AVN is more common in the age group of 30-60. The person with avascular necrosis has to undergo treatment. If untreated, the joints have the chance to collapse and bones can lose their shape. Generally, hips get more affected by AVN.
The other names for Avascular Necrosis(AVN) are Osteoarthritis, Ischemic bone disease, Aseptic necrosis, Osteonecrosis, and Bone infarction.
Associated Anatomy of Avascular Necrosis
Bone tissue of the body
Alternate Name of Avascular Necrosis
The other names for Avascular Necrosis(AVN) are Osteoarthritis, Ischemic bone disease, Aseptic necrosis, Osteonecrosis, and Bone infarction.
Avascular Necrosis Causes
Although the correct reason for AVN is not known, in most cases, Avascular necrosis is caused by one or a combination of the following factors:
- Injury: The main reason for Avascular necrosis is slowing down or lack of blood supply to the bone tissue of the injured site.
- Alcohol consumption: People who consume more alcohol have a higher risk of developing Avascular necrosis.
- Smoking: People who smoke have a higher risk of getting infected with Avascular necrosis.
- Blood vessels deposited with fat: Fat deposition in the blood vessels can lead to a lack of blood supply to the bones of the affected organ.
- Disease: Diseases like Legg-calve Perthes disease can cause AVN
- Medication: Taking high doses of medications like corticosteroids, as a treatment of any chronic disease for a prolonged time can cause AVN.
- Less common factors: There are a few other factors which are less common and can be a cause of AVN are listed below
- Bends disease, decompression sickness
- Gaucher’s disease
- Chemotherapy or medications (containing bisphosphonates) to treat cancer
- Infection by Human Immunodeficiency Virus (HIV)
- Sickle cell anaemia
- Lupus
- Pancreatitis
- Organ transplant
- High cholesterol
Avascular Necrosis Symptoms
Early-stage Avascular necrosis rarely causes any symptoms. In most cases, symptoms may occur as the pain becomes invasive. In the initial stages, the pain will be mild. When you do some work by using the affected area, the pain will be moderate to severe. Then, it starts to hurt more often in the affected joint. The final stage is when the condition worsens and the joint of the affected bone collapses and becomes immovable.
Avascular Necrosis Diagnosis
Doctors diagnose Avascular necrosis by inquiring about the patient’s medical history, signs, symptoms, and a physical examination, followed by diagnostic imaging tests. The doctor checks your joint by moving it to different positions and checks for the response. To conclude whether it is due to AVN or any other problem, imaging may be done.
- MRI and CT scan - This can reveal early stages of bone tissue death by AVN.
- X-Ray - This can reveal the only later stage of AVN. The early stage of AVN appears normal in the X-Ray
- Bone scan - Using a tracer based technique, defective bone tissue can be detected.
Avascular Necrosis Treatment
The Avascular necrosis treatment usually depends on the patient’s overall health condition and severity of disease conditions and includes factors such as age, area affected, cause of the AVN, and severity of AVN.
Hip bones and knee bones are most commonly affected in the case of AVN. The other less commonly affected bones include the ankle, feet, hands, wrist, and shoulder.
Some common treatment options include:
- Medications like anti-inflammatory non steroids like ibuprofen, naproxen sodium
- Medications for osteoporosis
- Blood thinner and cholesterol controlling drugs
- Electrical stimulation to bring bone reformation
- Exercise guided by Physiotherapists and proper rest
Surgery Options in the Advanced Stage of AVN
In the advanced stage of avascular necrosis, surgery is recommended. Some of the options are:
- Graft or bone transplant (especially kidney transplant)
- Osteotomy or reshaping of the bone
- Replacement of the affected joint
- Core decompression (Removal of the inner layer of the bone enables new bone tissue formation)
- Stem cell treatment (Stem cells taken from the affected joint can rejuvenate and form new tissues).
Risk Factors of Avascular Necrosis
- Bisphosphonate use - The use of bisphosphonate for treating cancer increases risk of AVN.
- Alcohol consumption - Excessive use of alcohol and smoking can induce formation of fats in blood vessels
- Trauma - Injury can result in reduced blood supply to the blood vessels
- Steroid use - Usage of corticosteroid for a long time or its high dosage can affect the blood supply by fat deposition.
Possible Complications of Avascular Necrosis
The possible complications of advanced Avascular necrosis are as follows:
- Persistent pain
- Broken bone
- Joint dislocation can happen if untreated
Avascular Necrosis Preventions
Some of the following measures may help lessen the risk of developing Avascular necrosis:
- Avoid smoking and consuming more alcohol
- Consult your doctor in case of taking corticosteroids
- Keep your cholesterol levels under control.
Epidemiology of Avascular Necrosis
The estimated incidence of Avascular necrosis is high in men compared to women. Avascular necrosis is highly prevalent in young adults and elderly people (aged between 30 and 60).
Expected Prognosis of Avascular Necrosis
Fortunately, recent advancements in diagnostic procedures, treatment options, and medication have drastically reduced the number of new cases of Avascular necrosis and its associated complications.
Natural Progression of Avascular Necrosis
Avascular necrosis doesn’t spread to other organs of the body. With time AVN of the affected site causes severe pain. The patient has to get medical treatment if not, it leaves the affected bone broken, immovable or joint dislocated.
Pathophysiology of Avascular Necrosis
Avascular necrosis is characterized by the death of bone tissue mostly resulting from trauma or injury.