What is osteoid osteoma?
Osteoid osteoma is a common benign tumor that usually develops in the long bones of the leg — the femur (thigh bone) and tibia (shin bone) – but can occur in any bone. In 7-20 percent of cases, osteoid osteoma occurs in the spine.
Osteoid osteomas are generally small (less than 2 centimeters). However, they can cause reactive bone to form around them and produce significant pain.
While osteoid osteoma can occur at any age, it is more common between the ages of 5 and 25, and nearly three times as likely to affect boys as girls.
Osteoid osteoma is often confused with other diseases such as osteomyelitis, osteoblastoma, Langerhans cell histiocytosis, or a stress fracture. Your child’s doctor may need to perform specific imaging tests to ensure an accurate diagnosis.
It is not known what causes osteoid osteoma.
Signs and symptoms
Symptoms of osteoid osteoma include:
- Dull, aching pain that comes and goes during the day
- Sharp pain at night, when your child is at rest
- A limp
Testing and diagnosis
At Children’s Hospital of Philadelphia (CHOP), our clinical experts use a variety of diagnostic tests to diagnose osteoid osteoma in children, including:
- X-rays, which produce images of bones.
- Computed tomography (CT) scan, which uses a combination of X-rays and computer technology to examine bones and produces cross-sectional images ("slices") of the body.
- 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.
- EOS imaging, an imaging technology that creates 3-dimensional models from two flat 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.
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.
Many osteoid osteomas will resolve on their own, but it may take several years. If your child is experiencing pain, he may benefit from nonsteroidal anti-inflammatory medications or regular analgesics such as aspirin, Tylenol® or ibuprofen.
For children with pain that cannot be relieved by over-the-counter medications, a procedure may be needed.
The gold standard for treating osteoid osteoma is CT-guided radiofrequency ablation (RFA). This minimally-invasive, outpatient procedure is performed in the Interventional Radiology Suite at Children’s Hospital of Philadelphia.
Your child is given anesthesia, then doctors use CT-guided imaging to pinpoint the center of the tumor. A radiofrequency probe is then inserted into the tumor and heated to burn off the tumor. In most cases, one treatment is all that is necessary, but RFA can be repeated if needed.
The procedure takes about two hours, followed by a two-hour recovery period, then your child can return home. RFA is used in about 90 percent of patients with osteoid osteoma.
In rare cases, doctors may need to perform an open surgical procedure called intralesional curettage, which involves scraping out the bone to completely remove the tumor, and filling the space with bone graft material.
If your child’s osteoid osteoma affected her spine, she may need additional treatment to reinforce her spine. Surgeons in the Bone and Soft Tissue Tumor Program will work closely with spine surgeons to ensure the best outcome for your child.
Though surgery for 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.
No matter which treatment your child received, regular follow-up care is important. Ongoing care is recommended until healing has occurred and your child no longer experiences symptoms related to osteoid osteoma. Your child’s doctor will set up a schedule for follow-up visits.
At Children's Hospital of Philadelphia, we offer ongoing support and services for patients and families 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.
During follow-up visits, X-rays and other diagnostic testing of the tumor site are recommended to closely monitor your child’s health.
Children with osteoid osteoma have good long-term outcomes.
Recurrence of osteoid osteoma is rare, but if it occurs, the tumor can be retargeted with radiofrequency ablation.