Osteoid = a substance produced by cells that make new bone
Osteoma = a type of tumor that develops in bones
Osteoid osteomas are small, benign bone tumors. Osteoid osteomas most commonly occur in the legs, hands, fingers and spine. At the Spine Hospital at the Neurological Institute of New York, we specialize in osteoid osteomas of the spine.
The bones of the spine are called vertebrae, and osteoid osteomas tend to affect the posterior (rear) portions of the vertebrae. They can occur in vertebrae at any level: cervical (neck), thoracic (upper- and mid-back), lumbar (lower back), or sacral (base of the spine).
Osteoid osteomas do not grow larger than 1.5-2 centimeters, or about .75 inches. A related tumor type, osteoblastoma, is very similar, but is usually larger than 2 cm.
Osteoid osteomas are known for causing a constant dull, aching pain. The pain is not made worse with activity, and is very often relieved by NSAIDs (nonsteroidal anti-inflammatory drugs, like aspirin). It is often worse at night, sometimes even waking people from sleep.
Spinal osteoid osteoma may cause muscle spasms that produce scoliosis, or a bending and twisting of the spine. This is especially common with osteoid osteomas in the lumbar region. Scoliosis caused by muscle spasm is generally painful.
Some osteoid osteomas, however, cause no symptoms at all.
Causes and Risk Factors
The causes of osteoid osteoma are not yet understood. It is a relatively common bone tumor. It is more common in males than females, and equally common across races. Most people diagnosed with osteoid osteoma are in the first, second and third decades of life.
Tests and Diagnosis
The following tests may be used in the diagnosis of osteoid osteoma:
- X-ray: scan that uses invisible beams of electromagnetic energy to produce images of internal tissues, bones, and organs on film. Pain is generally present before the osteoid osteoma is visible on X-ray, so diagnosing these tumors often takes some time.
- CT (computed tomography) scan: uses a combination of X-rays and computer technology to produce detailed images of bones and soft tissues. CT scans can help pinpoint the extent of the tumor.
- MR (magnetic resonance) scan: uses magnets, radio waves, and computer technology to produce images of organs and tissues like the brain and spinal cord. MR scans may be able to rule out other diagnoses, but these scans alone are not useful in diagnosing osteoid osteoma.
- Biopsy: a procedure in which tumor tissue is removed for study in the laboratory. A biopsy can confirm the diagnosis of osteoid osteoma.
Spinal osteoid osteomas are often managed conservatively (non-surgically) when possible. In general, the pain caused by osteoid osteomas is particularly well-suited for treatment with NSAIDs. Many patients find lasting relief with this type of management, without any of the drawbacks or potential risks of surgery.
Some cases prove difficult to manage with NSAIDs. In these cases, surgery to remove the tumor relieves the pain. Recurrence rate of the tumor after surgery is low.
Spinal osteoid osteomas that cause muscle spasm and scoliosis should be effectively treated, by either measure, before the scoliosis develops into a structural problem.