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from the American Academy of Orthopaedic Surgeons

Diseases & Conditions



Staying Healthy


Osteoblastoma is a benign (noncancerous) bone tumor. It is a rare tumor that often develops in the bones of the spine, as well as the legs, hands, and feet.

Adolescents and young adults are most often affected by osteoblastoma. The tumors typically appear between the ages of 10 and 30 years, and they are twice as common in males as in females.

Because osteoblastomas destroy healthy bone and can grow to a large size, treatment always involves surgery to remove the tumor.


Osteoblastoma is a slow-growing tumor that dissolves normal, healthy bone and makes a new type of abnormal bone material called osteoid. This osteoid bone material builds up around normal bone. Because the osteoid bone is weaker than normal bone, the area surrounding the tumor becomes more vulnerable to fracture. A bone weakened by an osteoblastoma can break with just a minor injury.

At their largest, osteoblastomas are usually over 2cm (1 inch) in diameter.

Although osteoblastoma is considered a benign tumor, it is locally aggressive. This means that it usually:

  • Destroys normal bone
  • Causes pathologic fractures (breaks in the bone that are caused by a disease rather than an injury)
  • Grows back after surgical treatment


The cause of osteoblastoma is not known.


Because osteoblastomas are slow-growing, the patients will typically have symptoms for about 2 years before the tumor is detected.

  • The most common symptoms of an osteoblastoma include a dull aching pain that gets worse over time. Taking non-steroidal anti-inflammatory drugs (NSAIDs), like ibuprofen, may help relieve pain. Night pain is not typical.
  • If the tumor is located in an extremity (arm or leg), the patient may experience swelling, weakness, or a limp.
  • If the tumor is located in the spine, the patient can experience back pain, neck pain, or nerve pain, as well as neurologic symptoms in the arms or legs, such as numbness, weakness, or pain. Osteoblastoma of the spine can also cause muscle spasms, which can result in scoliosis, a sideways curve of the spine. Fortunately, this curve usually resolves after the osteoblastoma has been treated.
osteoblastoma that caused spinal curve

 (Left) Normal lumbar (lower) spine anatomy. (Center) A magnetic resonance imaging scan of an osteoblastoma in the lower back that has caused a scoliosis curve. (Right) The same osteoblastoma shown in a computerized tomography scan.

Doctor Examination

Medical History and Physical Examination

There are many aspects to the doctor's examination. Before a physical examination, your doctor will talk with you about your general health, as well as your symptoms, to get a good history of the problem.

During the physical examination, your doctor will look for tenderness over the bone and check your range of motion in the painful area.


Your doctor will order imaging and tissue tests to diagnose osteoblastoma.

X-rays. X-rays provide images of dense structures, such as bone. Results from the X-rays will help your doctor determine whether more imaging scans are needed.

x-ray and mri of osteoblastoma

(Left) An X-ray of an osteoblastoma on a patient's ring finger. (Right) An MRI scan of the same osteoblastoma shows the tumor mass in greater detail.

Other imaging tests. Your doctor may also request computerized tomography (CT) scans, magnetic resonance imaging (MRI) scans, or bone scans to help further define the tumor. These scans can provide more detail, especially of soft tissues. They can also provide cross-sectional images.

A CT scan or MRI scan will show your doctor more precisely where the tumor is located and what its specific characteristics are.

Biopsy. A biopsy is often necessary to confirm an osteoblastoma diagnosis. In a biopsy, the doctor takes a tissue sample of the tumor and examines it under a microscope. Your doctor may give you a local anesthetic to numb the area and take a sample using a needle. Biopsies can also be performed in the operating room with a small surgical procedure.

Osteoblastoma and Osteoid Osteoma

Osteoblastoma is closely associated with another benign bone tumor: osteoid osteoma. Both tumors form abnormal osteoid bone material, and both occur more frequently in younger people, particularly males.

These are the key differences between the two types of tumors:

  • Osteoblastomas are usually over 2cm (1 inch) in size. Osteoid osteomas are smaller than osteoblastomas, and they do not grow.
  • Pain from osteoid osteoma often worsens at night, but it can be relieved with NSAIDs, like ibuprofen. Osteoblastomas do not typically cause night pain, and the pain does not respond as well to NSAIDs.
  • Osteoblastoma requires surgery to remove the growing tumor. Osteoid osteoma does not require surgery if the associated pain can be managed with NSAID treatment.


Treatment for osteoblastoma requires surgery. Most commonly, surgery involves scraping out the tumor (curettage) and filling the hole with bone graft material.

Curettage and Bone Grafting

In this procedure, the tumor is scraped out of the bone.

  • In some cases, the hole is filled with a bone graft — this is bone taken from a donor (allograft) or from another bone in your body (autograft).
  • Your doctor may also use a bone graft substitute or bone cement to fill the hole.
  • Sometimes, your surgeon may need to support the bone using plates and screws

Spine Tumors

Treatment for tumors in the arms and legs is usually straightforward; however, there may be more challenges when the tumor is located in the spine.

After a tumor is removed from the spine, a spinal fusion may be needed to support the area. Spinal fusion is essentially a "welding" process. The basic idea is to realign and fuse together the weakened spinal bones so that they heal into a single, solid bone.

En Bloc Resection

In some cases, the best surgical option is to remove the entire tumor and reconstruct the bone. This is most common for:

  • A large, destructive tumor
  • Cases with multiple recurrences (meaning, the tumor has grown back after removal more than once)


If the osteoblastoma cannot be safely removed with surgery, your surgeon may consider:

  • Cryotherapy (freezing the tumor)
  • Radiofrequency ablation (burning the tumor)

Radiation Therapy and Chemotherapy

These treatment options are not recommended for osteoblastoma except in rare circumstances. For example, if the tumor is located in the spine and the surgeon cannot safely remove the entire tumor, radiation therapy is sometimes recommended.


How long it will take to return to daily activities depends on where the tumor was located and which procedure you had to remove it. Your doctor will provide you with specific instructions to guide your rehabilitation.

Osteoblastoma returns in approximately 15 to 25% of patients. The likelihood of the tumor coming back is related to how well it can be completely removed without causing damage to normal structures.

If the tumor does come back, it can be treated using the same methods. Your doctor will talk to you about all the options.

Last Reviewed

April 2024

Contributed and/or Updated by

Alexandra Kathleen Callan, MD, FAAOSRajiv Rajani, MDRobert H. Quinn, MDOwen Ala, MD

Peer-Reviewed by

Thomas Ward Throckmorton, MD, FAAOSStuart J. Fischer, MD

AAOS does not endorse any treatments, procedures, products, or physicians referenced herein. This information is provided as an educational service and is not intended to serve as medical advice. Anyone seeking specific orthopaedic advice or assistance should consult his or her orthopaedic surgeon, or locate one in your area through the AAOS Find an Orthopaedist program on this website.