Osteoid Osteoma: What is it and how is it treated?

Osteoid osteoma is a benign bone tumor. It occurs most often in the long bones of the lower limbs (legs) and mainly in the femur, but can occur in the bones of the hand and sometimes in the lower vertebrae. It occurs extremely rarely in the bones of the head and face.

Osteoid osteomas are very small tumors that are no larger than 1.5 cm in diameter. They usually occur in adolescence or young adulthood and are more common in men than women. These tumors, while causing pain locally in the bone, do not worsen the bone.

Osteoid osteomas in children can deform or stimulate the bone and make it larger or longer if they are located in areas of the bone growth zone. If they are close to joints they can lead to swelling of the joint or collection of fluid in the joint. They do not extend beyond the bone and do not metastasize.

What is the cause of osteoid osteoma?

Osteoid osteoma is caused when certain cells divide uncontrollably resulting in a small mass. This mass is poor quality bone, which replaces healthy bone. However, it is not known why this disorder occurs.

What are the symptoms of osteoid osteoma?

The most common symptoms are the following:

• Mild or acute pain, worsening at night
• The pain usually goes away with an anti-inflammatory drug
• Lameness (i.e. difficulty walking)
• If the tumor is in the spine, scoliosis and pain from muscle spasm or sciatica may occur.
• If the tumor is in the bone growth zone, growth may be affected
• Near muscle atrophy
• Bone curvature

The symptoms may be similar to those of other illnesses, so you should always consult your doctor.

How is osteoid osteoma diagnosed?

• The patient’s history is needed
• Clinical examination by the doctor
• Blood tests: General blood and biochemical test
• X-rays of the diseased bone
• X-ray computed tomography
• Brain scans
• Bone scan

How is osteoid osteoma treated?

The treatment is determined by the Orthopedist and depends on:

• Age
• The general health of the body
• The extent of the tumor
• The patient’s resistance to various drugs or therapeutic techniques

Traditionally the osteoid osteoma is surgically removed by the Orthopedist with various surgical techniques, depending on the case.

Recently, the ablation of the tumor with transdermal radiofrequency is being performed by a radiotherapist. This technique is applied under general anesthesia and with simultaneous computed tomography. With this method, radio frequencies are injected under the skin with a needle, in order to destroy the tumor cells. This method is minimally invasive and has successfully replaced surgery, but does not apply to tumors in the spine.

What is the long-term prognosis of a patient with osteoid osteoma?

The prognosis is generally excellent, although it varies from person to person and depends on:

• How active the tumor is
• Tumor’s behavior in treatment
• The age and state of health of the patient

Most of these tumors are successfully treated. They may, however, recur, which requires regular monitoring of the patient with osteoid osteoma. The manner and frequency of monitoring should be determined by the physician.

Advisors: Aikaterini Deli, doctor Georgia Karachristou, doctor Susana Gazi, MD, doctor, Rheumatologist