What is osteoblastoma?

Osteoblastoma is a rare benign bone tumor that accounts for about 1 percent of all primary bone tumors in the United States. It affects twice as many boys as girls.

Similar to most primary benign bone tumors, osteoblastoma tends to form in the extremities, however it also often forms in the spine. It can also occur in any of the bones in the hands and feet.

Osteoblastoma can be difficult to diagnose because it can manifest in different ways — as a slow-growing tumor or as a more aggressive tumor that invades surrounding tissue and bone. It may also occur in conjunction with an aneurysmal bone cyst, another benign tumor.

Osteoblastoma is also closely related to osteoid osteoma, a more common benign bone tumor, but differs in that an osteoblastoma can grow larger than an osteoid osteoma and it has different symptoms.

If an osteoblastoma is located on or in the spinal column, it can cause scoliosis and neurological symptoms.


It is not known what causes osteoblastoma.

Signs and symptoms

Symptoms of osteoblastoma include:

  • Sustained pain (which is less likely to respond to over-the-counter common pain relievers like Tylenol or ibuprofen)
  • Swelling and tenderness
  • Pinched nerve (nerve compression) in the spine

Testing and diagnosis

The clinical course of osteoblastoma can make it difficult to diagnose. The tumor can grow slowly or quickly, and its symptoms and clinical features can be confused with other tumors such as osteoid osteoma, giant cell tumor of bone and fibrous dysplasia.

If your child has been referred to an orthopaedic specialist, your child’s diagnostic evaluation begins with a thorough medical history and physical examination.

At Children’s Hospital of Philadelphia (CHOP), clinical experts use a variety of diagnostic tests to diagnose osteoblastoma, including

  • X-rays, which produce images of bones.
  • Magnetic resonance imaging (MRI), which uses a combination of large magnets, radiofrequencies and a computer to produce detailed images of organs, soft tissues, muscles, ligaments and other structures within the body. Your child is exposed to no radiation during an MRI.
  • Computed tomography (CT) scan, which uses a combination of X-rays and computer technology to produce cross-sectional images ("slices") of the body.
  • EOS imaging, an imaging technology that creates 3-dimensional models from two planar images. Unlike a CT scan, EOS images are taken while the child is in an upright or standing position, enabling improved diagnosis due to weight-bearing positioning.
  • Needle biopsy, which is a procedure where a doctor places a small needle through the skin and into the lesion to withdraw a small sample of the abnormal tissue. The tissue is analyzed to confirm any findings.

In addition to diagnosing the specific type of cancer, these tests will also help determine the size and location of the tumor, and stage of the cancer. All of this information is crucial in determining the best treatment option for your child.


There are many treatment options available for bone and soft tissue tumors, and some children will need a combination of these therapies. At CHOP, experts at the Bone and Soft Tissue Tumor Program take a team approach to treatment. Orthopaedic and other specialists collaborate to provide your child with individualized care and the best possible outcomes.

Our program is led by Kristy L. Weber, MD, and Alexandre Arkader, MD, nationally renowned surgeons who specialize in treating bone and soft tissues tumors, limb-sparing surgery and reconstructive surgery.

Surgical treatment may include:

  • Intralesional curettage, which involves scraping out the bone to completely remove the tumor
  • Intraoperative adjuvants — such as cryotherapy (liquid nitrogen), phenol (a chemical) or cauterization (burning the tumor bed) — which are used to remove microscopic tumor cells
  • Bone grafting, a surgical procedure to replace missing bone with artificial graft material or cadaver bone

Depending on the size and location of osteoblastoma removed, your child may be able to return home that day or may spend one night in the Hospital.

Surgical safety

Though surgery for malignant tumors is highly effective, we understand that any surgery can be a stressful experience for children and families. At CHOP, we offer a wealth of resources about how to prepare your child for surgery and what to expect during surgery.

Additionally, we employ numerous best practices before, during and after surgery to decrease the risk of infection and increase positive outcomes. For more details about safety protocols at Children's Hospital of Philadelphia, see safety in surgery.

Follow-up care

After surgery for osteoblastoma, your child will return for check-ups one to two weeks after surgery, then again at three and six months post-surgery.

Osteoblastoma can reoccur in about 10 percent of cases — even after being successfully treated — so it is important for your child continue to be seen regularly by one of the physicians at the Bone and Soft Tissue Tumor Program.

During follow-up visits, X-rays and other diagnostic testing of the tumor site or other areas may be recommended to closely monitor your child’s health.

If your child’s osteoblastoma affected his spine, he may need additional treatment from CHOP’s Spine Program or the Division of Orthopaedics.

At CHOP, we offer ongoing support and services for your child and family at our Main Campus and throughout our CHOP Care Network. Our team is committed to partnering with parents and referring physicians to provide the most current, comprehensive and specialized care possible for your child.

If your child needs continued monitoring into adulthood, he can continue to see some of the same doctors who treated him. CHOP’s Bone and Soft Tissue Tumor Program works closely with Penn Medicine. For families who live farther away and need continued monitoring, our clinical professionals will help your child transition to adult care near home.


Long-term outcomes for children with osteoblastoma are good. 

Reviewed by Kristy L. Weber, MD, FACS, Alexandre Arkader, MD

Providers Who Treat Osteoblastoma

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