An osseous hemangioma is a benign (noncancerous) tumor made up of abnormal blood vessels that grows within bone. These are among the most common benign bone tumors, accounting for about 1% of all primary skeletal tumors. The vast majority are found by accident on imaging done for something else entirely and never cause symptoms.
Where Osseous Hemangiomas Develop
About 75% of osseous hemangiomas grow in the spine or skull. The spine is by far the most common location, and vertebral hemangiomas show up in roughly 10% to 26% of adults depending on the imaging method used and the size of the lesions counted. A study published in the European Spine Journal found them in 26% of individuals studied, suggesting the true prevalence is higher than older estimates.
The remaining cases appear in the shoulder blade, ribs, collarbone, pelvis, and occasionally the long bones of the arms and legs. When long bones are involved, the tibia and femur are the most frequent sites, with the lower extremities accounting for about 73% of those cases.
What Causes Them
The exact cause is still unknown. Two leading theories point to either a congenital origin (something present from birth) or a response to trauma, though neither has been proven. In some reported cases, a prior injury to the area preceded discovery of the tumor. Inside the bone, the growing mass of blood vessels triggers a cycle of bone breakdown and rebuilding, reshaping the surrounding bone into distinctive patterns that doctors can recognize on scans.
Why Most People Never Have Symptoms
The overwhelming majority of osseous hemangiomas are completely silent. You could have one in your spine for decades and never know. They turn up as incidental findings when you get a CT scan or MRI for back pain, a car accident, or another unrelated problem. Reading “hemangioma” on your radiology report can sound alarming, but these lesions almost never require treatment.
Fewer than 2% of vertebral hemangiomas ever cause symptoms. When they do, it typically means the tumor has grown aggressively enough to expand beyond the bone and press on nearby nerves or the spinal cord. Symptoms in those rare cases can include dull, aching back pain at the level of the tumor, numbness or tingling below that level, progressive weakness in the legs, and difficulty walking. These aggressive hemangiomas tend to have less fat content and more blood vessel density than the typical harmless ones.
How They Look on Imaging
Osseous hemangiomas have distinctive appearances that usually make them easy for radiologists to identify. On a CT scan of the spine, they produce two classic patterns. Viewed from the side, thickened vertical bone stripes create what’s called a “corduroy” pattern, like the ridged fabric. Viewed from above in cross-section, those same stripes appear as scattered dots, known as the “polka-dot sign.” Both patterns result from the tumor replacing normal bone and leaving behind reinforced vertical columns.
On MRI, typical hemangiomas appear bright on both T1 and T2 sequences because of their high fat content. This brightness is one of the key features that separates them from more concerning bone lesions. Hemangiomas in the skull produce their own signature: a “sunburst” or “sunray” pattern on CT, where bony spicules radiate outward from the center of the tumor like the spokes of a wheel.
Telling Hemangiomas Apart From Cancer
In people with a history of cancer, distinguishing a hemangioma from a bone metastasis matters enormously. Typical hemangiomas are straightforward to identify, but atypical ones with less fat can mimic the appearance of cancer on standard MRI. Specialized imaging techniques, including chemical-shift imaging and fat-suppressed sequences, can differentiate the two with accuracy above 90%. This distinction prevents unnecessary radiation or chemotherapy for what turns out to be a harmless growth.
Types of Osseous Hemangioma
Under a microscope, osseous hemangiomas are classified into two main types based on the size of their blood vessels. Capillary hemangiomas contain small, tightly packed vessels filled with red blood cells. Cavernous hemangiomas have larger, dilated blood-filled spaces, sometimes with blood clots forming inside them. The cavernous type is more common in the spine. This distinction matters mainly to pathologists; for most patients, the behavior of the tumor and its location are more relevant than its microscopic subtype.
Treatment for Symptomatic Cases
If your hemangioma was found incidentally and isn’t causing problems, the standard approach is simply to leave it alone. No follow-up imaging is typically needed for a classic-appearing vertebral hemangioma.
For the small number of cases that do cause pain or neurological symptoms, several treatment options exist. Vertebroplasty or balloon kyphoplasty involves injecting bone cement into the affected vertebra to stabilize it and relieve pain. Ethanol injection works by destroying the lining of the blood vessels inside the tumor, cutting off its blood supply and causing it to shrink. Radiation therapy can also be used to reduce the tumor’s size and relieve pressure on nerves. Radiofrequency ablation uses heat to destroy the abnormal tissue.
When the tumor causes significant nerve compression, especially with progressive leg weakness, surgical decompression becomes necessary. This involves removing part of the vertebral arch to relieve pressure on the spinal cord, sometimes combined with removal of the tumor itself. How completely the tumor is removed affects the chance of it coming back. One study found a 20% recurrence rate after partial removal, while complete removal of the entire affected vertebral segment resulted in no recurrences. After vertebroplasty alone, the four-year recurrence rate was about 5.4%.
Long-Term Outlook
For the vast majority of people, an osseous hemangioma is a permanent but completely harmless part of their skeleton. It will not transform into cancer. Even in the rare aggressive cases that require treatment, outcomes are generally favorable once the pressure on nerves is relieved. Recurrence rates vary by treatment approach, ranging from around 5% after cement injection to 14% to 27% after partial surgical removal, but complete resection offers the lowest risk of the tumor returning.