Osteoid osteoma is a noncancerous tumor in your long bones. This tumor often occurs in your shin and thigh bones. Providers diagnose these tumors with X-rays and bone scans. Osteoid osteomas may go away on their own. Providers also treat them with NSAIDs or surgery. Once treated, people with an osteoid osteoma usually live long, full lives.
An osteoid osteoma is a noncancerous (benign) bone tumor. Each tumor usually measures less than 1 inch across. These tumors don’t grow or spread anywhere else in your body.
Osteoid osteomas most often develop in the long bones of your body. These long bones include your shin (tibia) and thigh (femur) bones. Osteoid osteomas may also form in your:
This condition usually causes aching, dull pain that worsens at night. Healthcare providers treat osteoid osteomas with non-steroidal inflammatory drugs (NSAIDs) or surgery.
Osteoid osteomas usually form in people between the ages of 5 and 25. This condition affects three times as many men as women. But osteoid osteomas can affect anyone no matter their gender, ethnicity or race.
Osteoid osteomas make up about 10% of all benign bone tumors.
Osteoid osteomas and osteoblastomas are both types of benign bone tumors. But osteoblastomas differ in that they:
Researchers don’t know the exact cause of an osteoid osteoma. Causes of this benign bone tumor may include:
The main symptom of an osteoid osteoma is achy, dull pain. This pain often gets worse at night. Activity has no effect on the pain.
Other symptoms may include:
Symptoms of a tumor near your joint may include:
Your healthcare provider will first ask about your symptoms and do a physical examination. They may ask you questions about the pain, such as:
If your provider suspects an osteoid osteoma, they may suggest tests including:
X-ray: This diagnostic imaging test creates pictures of your bone. In an X-ray, an osteoid osteoma will appear as thickened bone that surrounds a small central core.
Three-phase bone scan: During a three-phase bone scan, your provider:
This scan helps your provider find the exact location of the tumor.
CT (computed tomography) scan or magnetic resonance imaging (MRI): A CT scan shows an image of your bone and can help identify an osteoid osteoma. An MRI is less accurate in showing an osteoid osteoma but can help rule out cancer.
Biopsy: During a biopsy, your provider removes a sample of the tumor. They look at this tissue under a microscope for signs of an osteoid osteoma. This biopsy also helps them to rule out other conditions.
Blood tests: Your provider may take blood tests to rule out an infection.
Osteoid osteomas may go away on their own. But these tumors may not disappear for years.
You can treat an osteoid osteoma with NSAIDs. NSAIDs can be nonprescription (aspirin, ibuprofen or naproxen) or prescription. NSAIDs help to relieve pain and may speed shrinkage of the osteoid osteoma. With this conservative treatment, symptoms usually end within 33 months (2.75 years).
Providers may suggest surgery to treat an osteoid osteoma. You will be asleep under general anesthesia or the area will be numb (regional anesthesia) during the surgery. The types of surgery include:
Curettage: During curettage, your surgeon removes the entire tumor. Your surgeon reaches the tumor through a cut in your skin.
CT-guided radiofrequency ablation: During minimally invasive radiofrequency ablation, your surgeon removes the tumor by heating it. Your surgeon will:
Usually, you need only one radiofrequency ablation treatment to remove the tumor.
You can’t reduce your risk of an osteoid osteoma. But you can look for the signs, so you can get prompt monitoring and treatment if needed.
What you can expect depends on what treatment you have.
Curettage: While curettage has a high success rate, complications may include:
CT-guided radiofrequency ablation: This procedure has a 90% success rate. But complications may include:
If you have curettage, you may need to stay in the hospital for a few days. After that, you may have physical therapy at home for several weeks before going back to work or school.
If you have radiofrequency ablation, you can usually go home that day. Most people can return to work or school in two or three days.
The outlook is very good. Osteoid osteoma can go away completely either with time, NSAIDs or surgery.
You can help to reduce complications after surgery if you:
A note from Cleveland Clinic
Osteoid osteoma is a noncancerous bone tumor. This tumor forms in your body’s long bones. Symptoms include pain that worsens at night, swelling and stiffness. Healthcare providers diagnose osteoid osteomas with X-rays and three-phase bone scans. Providers treat osteoid osteomas with non-steroidal inflammatory drugs (NSAIDs) or surgery. Osteoid osteomas can go away on their own over time or with treatment.
Last reviewed by a Cleveland Clinic medical professional on 02/04/2022.
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