Avascular necrosis can be described as a condition in which there is the death of bone tissues, as a result of a lack of the supply of blood. This condition is also referred to as osteonecrosis. It usually leads to tiny breaks in the bone, before the bone eventually collapses. Some of the risk factors for this disease include bone fractures, dislocation of the joints, alcoholism, and the consumption of high-dose steroids. This disease can also occur without an apparent cause. The femur is the most commonly affected bone in the body. Other body parts usually affected include the bones of the arm, forearm, knee, ankle and so on. Diagnosis is done through medical imaging. Examples of this include Computer tomography scan, MRI, and X-ray. A biopsy is also used, however, this is uncommon. Some of the treatment procedures for this disease include medication, stretching, surgery. Also, males are more affected than females. Patients are encouraged to stretch often but are told not to walk in the affected limb. Surgical procedures may involve processes such as decompression, osteotomy, bone grafts, or replacement of the joint. Statistics have shown that this disease is more prevalent in people between the ages of 30 to 50 years old. Stem cells and exosome are one of the potential ways of treating this disease. Scientists are working on ways to start using autologous bone marrow stem cells for the treatment of osteonecrosis.
What Are the Signs and Symptoms of Avascular Necrosis?
A lot of people don’t present with symptoms in the initial stages of the disease. However, patients start to feel pain, as the condition worsens. They might find it difficult putting weight on their joint. This disease can affect any bone in the body. Although, the disease mostly affects some specific part of the body like the shoulder, knee and the hip. The majority of the cases do affect multiple parts of the body at the same time. As mentioned earlier, the most affected part of the body is the thigh bone, also known as the femur. Below are some of the signs and symptoms of Avascular necrosis;
- Pain – The level of this pain is directly related to the severity of the disease. Patients feel more pain, as the disease progresses. They might not feel the pain initially until some pressure is applied to the affected bone. Eventually, the pain would increasingly worsen, as the disease progresses, even without having to apply any pressure on the affected part.
- Walking difficulties – Patients develop a difficulty in walking, as the disease progresses. Persons affected by this disease could also develop a limp as a coping mechanism for the pain and sometimes this persists after medical treatment and requires physiotherapy to gain a normal gait again.
- Stiffness of Joints – Due to the pain associated with avascular necrosis. Persons affected by this disease usually develop a coping mechanism. This coping mechanism could involve not using the affected joint and as a result, the joint could become stiff. This can also be treated with physiotherapy.
What Are The Causes Of Avascular Necrosis?
Avascular necrosis happens when there is a stoppage or interruption to the flow of blood to the bones. This reduction in the supply of blood to the bone can be caused by various reasons. Some of them include
- Trauma to the bone: Injuries such as a joint dislocation, can lead to the damage of the blood vessels in the joints.
- Radiotherapy: Patients undergoing cancer radiation treatment also tend to have a weakening of their bones and blood vessels.
- Other causes: There are some diseases that can lead to the development of avascular necrosis. Some of them include Sickle cell anemia, and Gaucher’s disease and so on. Some of them are as follows;
- Gaucher’s disease: This is a metabolic disease that causes the accumulation of fatty substances in the organs. This disease is hereditary, meaning it can be passed down from parents to their offspring.
- Sickle cell disease: This is blood disorder in which patients do have an abnormal hemoglobin. Their hemoglobin is sickle-shaped.
- Autoimmune diseases: These are diseases in which the immune system of the body fails to recognize the body tissues. It is an immune system disease in which the immune cells attack the tissues, causing various levels of injuries and damage. Some of these diseases might lead to the interruption of the supply of blood to the bones.
- Medications: There are some drugs that predispose patients to osteonecrosis. Examples of these drugs are the ones used in the treatment of cancer. This includes radiation and chemotherapy drugs
- HIV infection
- Inflammation of the pancreas
What Are The Risk Factors Of Avascular Necrosis?
There are some conditions that increase the risk of developing avascular necrosis. Some of these factors include the following;
- Steroid use: The consumption of high-dosage steroids is one of the prevalent causes of avascular necrosis. The exact reason behind this isn’t fully understood yet.
- Alcoholism: Drinking large units of alcohol on a regular basis, could lead to the accumulation of fat in the blood vessels. This would obstruct the flow of blood to the bones, eventually leading to avascular necrosis.
- Trauma: Injuries such as a joint dislocation, can lead to the damage of the blood vessels in the joints.
- Bisphosphonate use: Using bisphosphonate for a long time can lead to the increase in the density of bones. This might cause the osteonecrosis of the jaw. Although, this is a rare complication. It’s common in patients on drug treatment for multiple myeloma and breast cancer.
- Radiotherapy: Patients undergoing cancer radiation treatment also tend to have a weakening of their bones and blood vessels. In addition, patients that had undergone a renal transplant, have a high chance of developing avascular necrosis.
The Use Of Stem Cell Therapy In The Treatment Of Osteonecrosis
Scientists are working on ways to start using autologous bone marrow stem cells for the treatment of osteonecrosis. This procedure involves a minimally invasive decompression procedure. This treatment is suitable for patients at the early stage of avascular necrosis.
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