Vertebral hemangiomas are the most common benign tumors found in the spinal column. The vast majority of these vascular growths are harmless and do not cause any symptoms. Up to 20% of adults may have a vertebral hemangioma, but only a small fraction—less than 5%—ever become symptomatic or require medical attention. These lesions are usually discovered incidentally during imaging like MRI or CT scans performed for other reasons. In rare instances, a hemangioma can grow aggressively, leading to structural damage or compression of neurological structures that necessitate intervention.
What Exactly is a Vertebral Hemangioma?
A vertebral hemangioma is a non-cancerous growth composed of a proliferation of thin-walled blood vessels within the bone marrow spaces of a vertebra. These lesions are typically confined to the vertebral body, the main load-bearing segment of the spinal bone. They are considered slow-growing lesions arising from a localized overgrowth of native tissue. Hemangiomas are often classified into two main types: capillary (small, thin-walled vessels interspersed with bone tissue) and cavernous (larger, dilated vascular channels). The majority of these growths contain significant fat, which gives them a characteristic appearance on imaging and correlates with their inactive nature.
Factors Determining Aggressiveness and Risk
A hemangioma exhibits aggressive features when determined by its size, location, and cellular composition. Lesions with low-fat content and a high vascular component are often hypervascular and more likely to cause symptoms.
Mechanical Weakening and Expansion
The main mechanism through which a hemangioma becomes problematic is the mechanical weakening and expansion of the bone. As vascular channels proliferate, they erode the surrounding bony structure, leading to a loss of vertebral height or a pathological compression fracture. This structural instability can cause severe localized pain and may lead to spinal deformity.
Spinal Canal Compression
Another significant risk factor is the tumor’s expansion beyond the vertebral body into the spinal canal. This extension can directly press on the spinal cord or the nerve roots exiting the spine. Lesions in the thoracic spine are often of greater concern because the spinal canal is naturally narrower, making neurological structures vulnerable to compression. Pregnancy is also considered a potential risk factor for symptomatic progression, possibly due to increased blood flow or hormonal effects.
Recognizing Signs of Neurological Complication
When a vertebral hemangioma causes harm, symptoms typically relate to the compression of neural elements. The most common initial symptom is localized back pain, which can be severe and worsen with movement or activity. This pain may be distinct from typical mechanical back pain, sometimes presenting even at rest.
Radiculopathy and Myelopathy
As the tumor expands into the spinal canal, it can impinge upon the nerve roots, leading to radiculopathy. This manifests as radiating pain, numbness, or tingling sensations (paresthesia) that travel along the affected nerve, typically into the arms or legs. Compression of the spinal cord itself, known as myelopathy, is a more serious complication. Signs of myelopathy include muscle weakness, difficulty with coordination, and trouble walking.
In the most severe cases, particularly with aggressive growth in the lower lumbar region, a patient may develop cauda equina syndrome. This involves the loss of sensation in the saddle area and a loss of normal bowel or bladder control. Cauda equina syndrome constitutes a medical emergency requiring urgent decompression.
Monitoring and Intervention Strategies
Management of a vertebral hemangioma depends on whether it is causing symptoms or exhibiting aggressive growth. For the vast majority of asymptomatic lesions, no treatment is necessary, and the standard approach is observation. Regular follow-up imaging is usually unnecessary unless the patient develops new pain or neurological symptoms.
Pain Management and Stabilization
If a hemangioma causes pain without neurological deficit or significant instability, conservative management is attempted first, including non-invasive pain relief methods. When persistent pain relates to a vertebral compression fracture, vertebroplasty may be used. This minimally invasive procedure involves injecting bone cement directly into the fractured vertebra to stabilize the bone and provide pain relief.
Advanced Interventions
For aggressively growing or symptomatic lesions causing neurological compromise, targeted interventions are required. Preoperative embolization is often utilized for highly vascular tumors to block the blood supply and reduce the risk of excessive bleeding during surgery. Surgical decompression, such as a laminectomy, may be performed to relieve pressure on the spinal cord or nerve roots. For lesions that have significantly compromised the entire vertebra, a vertebrectomy followed by spinal reconstruction may be necessary. Radiation therapy is another option, used to stop tumor growth or as an adjuvant treatment after surgical resection. The choice of treatment is individualized based on the precise location, the degree of neurological deficit, and the overall stability of the spine.