Avascular necrosis of the hip (also called osteonecrosis or aseptic necrosis) is a painful condition that occurs when the blood supply to the head of the femur (thighbone) is disrupted, leading to tiny breaks in the bone, causing it to collapse. Although it can occur in any bone, osteonecrosis most commonly affects the hip and, in many cases, both hips are affected by the disease.
Causes of avascular necrosis
Avascular necrosis can be caused by disease, or by severe trauma, such as a fracture or dislocation, that affects the blood supply to the bone. It can however also occur without trauma or disease with some possible causes including excessive alcohol use, oral or intravenous steroids, radiation or chemotherapy, HIV, clotting disorders, and others.
Symptoms of avascular necrosis
There are usually no symptoms in the early stages with avascular necrosis however, as the damage worsens you may experience pain, limping and limited range of motion in the groin. If avascular necrosis is not treated, the joint deteriorates, leading to severe arthritis.
Diagnosing avascular necrosis
To diagnose avascular necrosis, Dr Singh will go through all your medical history, followed by a physical examination. Your medical history is compiled by asking you questions about your hip pain, any medications you may be taking, and prior injury and other bone and joint problems you may have. The physical examination will evaluate your range of motion and Dr Singh will observe how you walk, sit, bend, and move which all assist with your assessment and diagnosis.
If avascular necrosis is suspected, Dr Singh will usually ask for x-rays and possibly a bone scan. This helps confirm the diagnosis and assess the severity of your condition so that it can be treated effectively. Dr Singh may also request an MRI or other tests to see soft tissue in the area.
Treating avascular necrosis
Treating avascular necrosis involves managing the weakened bones and addressing the underlying cause. Depending on the severity, several treatment approaches may be used including conservative approaches to manage your pain symptoms:
- Medications: Nonsteroidal anti-inflammatory drugs (NSAIDs) can help relieve pain and reduce inflammation. If AVN is caused by an underlying condition such as lupus or sickle cell disease, medications to manage those conditions may also be prescribed.
- Physiotherapy: Exercises can help improve joint function and reduce pain. Physiotherapy may also include range-of-motion exercises, stretching, and strengthening exercises.
- Electrical stimulation: A technique called pulsed electromagnetic field therapy (PEMF) may help stimulate the growth of new bone tissue.
- Rest and activity modification: Reducing stress on the affected bone can help prevent further damage and in some cases, using crutches or a walker may be necessary.
- Surgery: If AVN is diagnosed in the early stages, surgery may be an option to preserve the joint and prevent further damage. Procedures such as core decompression, bone grafting, or joint replacement may be necessary in more advanced cases.
- Osteotomy: This is a procedure where the bone is cut and realigned to relieve stress on the affected area.
The choice of treatment depends on the stage of AVN, the size and location of the affected bone, and the patient’s overall health. It is important to seek medical advice and treatment as soon as possible to prevent further damage to the bone and joint.
