- Causes of AVN
- Signs & Symptoms
- Related Resources
Avascular necrosis (AVN) of the hip, also called femoral head avascular necrosis, is most common. The thigh bone is called the femur and the head of the femur is called the femoral head. This head attaches to the socket in the pelvic bone forming the hip joint. Other areas that may be affected are the shoulders, knees, hands and feet. The bone breaks down and eventually collapses.
AVN of the hip could be caused by fracture, joint dislocation, certain medical conditions, excessive alcohol intake or long-term use of high-dose steroid medications. The causes of AVN and the treatment used are the same, irrespective of which joint or bone is affected. The condition can affect anyone but is mostly seen in people 30 to 50 years of age.
What are the causes of avascular necrosis?
In about one-fourth of cases, the cause of avascular necrosis (AVN) remains unknown. However, in other cases, it is a secondary condition that occurs when blood flow is reduced or cut off, which can be caused by:
- Trauma to bone or joint
- Steroid therapy (especially in young people)
- Cancer treatments involving radiation to or near the bone or joint
- Fatty deposits in blood vessels or even fat emboli (fat clots), which can block the blood vessels that supply the bone and joint
- Certain medical conditions can reduce blood flow to the bone, such as:
Risk factors for developing avascular necrosis include:
What are the signs and symptoms of avascular necrosis?
In the initial stages, avascular necrosis (AVN) may not have any symptoms. However, as the condition progresses, it presents itself with mild pain that increases in severity over time. While pain might only result from putting weight on it at first, eventually, the pain may arise even when you’re at rest. This is followed by a limited range of motion for the joint.
Pain from AVN of the hip typically centers on the groin, thigh or buttock. Though, other areas that may be affected include the shoulder, knee, foot and hand. Some people develop the condition on both sides (bilaterally), such as in both hips.
How is avascular necrosis diagnosed?
To diagnose avascular necrosis (AVN), your doctor will conduct a complete physical exam and advise the following tests:
- Blood tests to rule out rheumatoid arthritis, sickle cell anemia, human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS), lupus and coagulation profile
- X-rays, magnetic resonance imaging (MRI) and computed tomography (CT) scan
- Radionucleotide bone scan
- Bone biopsy
- Functional evaluation of bone (measuring the pressure inside the bone via surgical intervention)
How is avascular necrosis treated?
The treatment of avascular necrosis (AVN) aims to provide symptom relief and prevent the condition from worsening. Surgery may be done if needed.
Treatment for AVN of the hips could include:
- Nonsteroidal anti-inflammatory drugs to help relieve pain
- Osteoporosis medications, such as alendronate, may paradoxically slow down the progression of avascular necrosis if used in the right dose and frequency
- Cholesterol-lowering medication to reduce the amount of cholesterol in the blood, which may help prevent the blockage of blood vessels due to lipid plaques.
- Using blood thinners under supervision to prevent clots in the blood vessels supplying the bones
- Adequate rest and restricting physical activity
- Using crutches to decrease the stress over the joint
- Rehabilitation and exercises under the guidance of a physical therapist
- Electrical stimulation to stimulate new bone growth to replace damaged bones
- Stem cells from the bone marrow aspiration and concentration is a newer procedure.
- This may help in the early stages of avascular necrosis of the hip by potentially growing new bone.
- Research is underway to confirm the efficacy of this treatment.
Surgical procedures may be recommended for advanced disease and may include:
- Bone graft or transplant: A section of healthy bone from another part of the body is used to strengthen the area of the affected bone.
- Core decompression: Part of the inner layer of the bone is removed.
- Bone osteotomy (reshaping): A wedge of bone is removed from the joint to help reduce the weight on the damaged bone.
- Joint replacement: Done if the bone has collapsed or other treatments failed, the damaged parts of the joint are replaced with plastic or metal parts.
How is avascular necrosis prevented?
The following measures can help reduce the risk of avascular necrosis (AVN):
- Since low vitamin D levels are associated with AVN, discuss with your healthcare practitioner about routine monitoring of your vitamin D levels and supplementation
- Avoiding smoking
- Limiting alcohol consumption
- Keeping your cholesterol levels in check
- Monitoring steroid use with the help of the doctor
- Never using exotic supplements for muscle building because these may be contaminated with steroids
Health Solutions From Our Sponsors
Barney J, Piuzzi NS, Akhondi H. Femoral Head Avascular Necrosis. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021. https://www.ncbi.nlm.nih.gov/books/NBK546658/
Top What Causes Avascular Necrosis of Hip Related Articles
Bone CancerBone cancer is a rare type of cancer that occurs in cells that make up the bones. Primary bone cancer that arises in bone cells is different than metastatic bone cancer, which is cancer that arises in another part of the body and then spreads to the bones. Hereditary and environmental factors likely contribute to the risk of bone cancer. Signs and symptoms of bone cancer may include pain, the presence of a mass or lump, and bone fractures. There are different types of bone cancer (osteosarcoma, chondrosarcoma, Ewing's sarcoma, pleomorphic sarcoma, fibrosarcoma). Treatment for bone cancer may include surgical removal of the tumor, chemotherapy, radiation, and/or a stem cell transplant. The prognosis for bone cancer depends on the type of cancer and the extent of spread.
Bone Density ScanBone density scanning measures bone mineral density, which helps a doctor decide whether a person is at increased risk of an osteoporosis-related fracture. The following risk factors may suggest the need for bone density scanning: advanced age, poor health, low body weight or thin stature, personal history of fracture as an adult, low physical activity, RA, and use of birth control pills.
Bone Marrow Transplant Risks and Survival RateThe life expectancy, survival rate and quality of life after a bone marrow transplant have improved considerably with more accurate genetic matching with donors, following up transplantation with an antibiotic regimen to control infections, and improved post-transplant care, in general.
What Conditions Do You Need a Bone Marrow Transplant for?Diseases of the marrow and blood can be debilitating or fatal, but for certain diseases, a treatment method is to implant some healthy bone marrow from a genetically compatible donor into a patient in the hope it will grow and replace the diseased marrow. Often, the patient’s own cancerous marrow is destroyed prior to restoring the patient’s marrow with the new healthy donor cells.
What Is the Difference Between a Bone Scan and a CT Scan?A bone scan and a computed tomography (CT) scan are both used to diagnose various bone conditions. The specific use of a bone scan is to diagnose active bone diseases, such as osteoporosis, Paget’s disease or the spread of cancer into the bone. A CT scan is a high-resolution X-ray that gives detailed information about organ anatomy.
How Can I Improve My Bone Health? 8 Lifestyle TipsBones are the substance that forms the skeleton of the body. They provide a rigid framework to your body and help you move around. Though maintaining bone health is vital in all ages of life, it becomes more of a concern in older people and postmenopausal women because of the increased risk of bone loss.
How Do You Detect Bone Cancer?Cancer means an uncontrolled growth of cells in the body. The term bone cancer is used for any cancer that starts in the bones. This is also called primary cancer of the bones. Cancers that begin in one part of the body and spread to bones (metastasis) are not categorized as bone cancer.
How Painful Is Bone Marrow Donor Procedure?This procedure takes place under general anaesthetic, so you won't feel any pain while it's happening.
Is a Bone Scan the Same as an MRI?A bone scan is a nuclear imaging technology, whereas magnetic resonance imaging (MRI) uses magnetic waves to create a three-dimensional (3D) image of an organ. Therefore, they are different.
Super Foods for Your BonesWhat sweetener is loaded with calcium? These bone-building super foods can help stave off osteoporosis, and many of them will surprise you.
What Does Bone Pain From Cancer Feel Like?Bone pain from cancer can be due to any type of cancer that forms or spreads in the bone. It may be due to primary bone cancer or secondary bone cancer. Secondary bone cancer, also known as metastatic bone cancer, is the one that has spread (metastasized) from another organ to the bone.
What Is Difference Between Bone Marrow Aspiration and Biopsy?Bone marrow biopsy and aspiration are procedures usually performed together to collect and examine bone marrow for helping in diagnosis of blood disorders and other conditions.
Where Does Bone Cancer Usually Start?Bone cancer occurs when there is an abnormal multiplication of the bone cells. It can arise from any bone in the body. The most commonly affected bones are the pelvis (hip bone) and long bones in the arms and legs such as the humerus and femur bone. Bone cancer is rare.