Orthopedic Surgery


Osteochondroma is one of the most common benign bone tumors in children, yet it is also one of the most silent. Because osteochondromas often display no symptoms, the tumors are generally only discovered when another problem is diagnosed. For many children, the tumors are never discovered.

Osteochondromas look like a bony projection on the external surface of a bone, like a bony mushroom on a stalk, usually near a growth plate. It can occur in any bone but is seen most often around the knee or the upper arm.

These tumors generally stop growing once a child stops growing. Most are found in patients younger than 20 years old and more often in males.

Osteochondromas are classified by stages and most of these tumors are stage I or II:

Cause of osteochondroma

It is unknown what causes osteochondromas. However, there is a theory these tumors may be the result of genetic abnormalities. Clinicians at The Children’s Hospital of Philadelphia are conducting research into this condition and its origins.

Symptoms of osteochondroma

Usually these tumors cause no symptoms. However, some can grow causing pain, deformity, growth disturbances and/or mechanical difficulties, depending on their location.

Diagnosing osteochondroma

At The Children’s Hospital of Philadelphia, clinical experts use a variety of diagnostic tests to diagnose osteochondroma, including:

In addition to imaging tests, a biopsy may also be necessary to confirm the diagnosis of osteochondroma. A biopsy is a short procedure where a sample of the growth is surgically removed and then tested for malignant and benign cells.

Your doctor will examine the tumor carefully to be sure it is not another type of tumor, such as a chondrosarcoma, which is cancerous.

Treatment of osteochondroma

If your child’s osteochondroma is fast-growing or affecting growth alignment, surgery may be necessary.

Though surgery for osteochondroma 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. See safety in surgery for details about safety protocols at The Children's Hospital of Philadelphia.

Treatment for osteochondroma is generally an en bloc resection, which is surgical removal of the entire growth and areas around the tumor. The tumor must be completely removed, leaving no remnants behind to ensure the tumor does not recur. The surgeon will be extremely careful not to harm the growth plate to ensure your child’s normal physical development after the operation.

Follow-up care

After surgery for osteochondroma, most patients can resume normal activities. However, in some cases, where the tumor was on a weight-bearing bone, your child’s physician may recommend restricted activity for your child to allow proper healing.

If the tumor caused no bone deformity or compromise of the growth plate, your child should follow-up with the doctor only if needed. If there are complications, your child should see a physician regularly to continue monitoring the condition.

Follow-up care and ongoing support and services are available 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.

Long-term outcomes

There is a 2-5 percent chance an osteochondroma will recur. The outcome and prognosis for osteochondromas after surgery is excellent.

In some cases, children with osteochondroma can develop hereditary multiple osteochondromas (HMO), previously called hereditary multiple exostoses (HME). The disorder is characterized by multiple osteochondroma growths and is inherited from one parent in 90 percent of cases. Because these genetic mutations run in families, it is advisable to have any siblings of the child with HMO to be examined by experienced medical professionals.


Contact us 

To make an appointment with the Division of Orthopedic Surgery at The Children's Hospital of Philadelphia, call 215-590-1527 or contact us online.

Reviewed by: Jason L. Katz, PA-C, MHS, ATC-R, and John P. Dormans, MD, FACS
Date: January 2013

  • Print
  • Share

Contact Us

Working Together
to Help Your Child

CHOP's Division of Orthopedic Surgery works closely with the Cancer Center to diagnose and treat children with benign and malignant tumors. Learn more about the Cancer Center at CHOP