Chronic low back pain is a common condition, but pinpointing the exact source of the discomfort can be challenging for both patients and healthcare providers. Vertebrogenic Low Back Pain (VLBP) represents a distinct diagnosis, differentiating it from pain caused by muscles, spinal discs, or facet joints. This type of pain originates not from the disc itself, but from the vertebral endplates and the adjacent bone marrow. The vertebral endplates are thin layers of cartilage and bone that serve as the interface between the vertebral body and the cushioning intervertebral disc.
Understanding Vertebrogenic Low Back Pain
The pain associated with VLBP stems from structural damage to the vertebral endplates, which are highly innervated with pain receptors. These endplates act as a bridge, distributing weight and facilitating nutrient exchange between the vertebral body and the disc. Damage to this structure, often from degenerative changes or microtrauma, triggers a pain response.
The pain signal is transmitted through a specific nerve pathway within the bone called the basivertebral nerve (BVN). The BVN runs through the center of the vertebral body and branches out to provide sensory input to the endplates. When the endplates become irritated or damaged, the BVN is activated, sending persistent pain messages to the brain.
Patients with VLBP typically describe a deep, aching, or burning sensation centralized along the midline of the lower back. This discomfort is often aggravated by activities that put mechanical stress on the spine, such as prolonged sitting, bending forward, or lifting. Unlike sciatica, the pain generally does not radiate down the leg below the knee, remaining primarily in the lower lumbar region.
The Inflammation and Modic Changes Connection
The underlying cause of chronic VLBP involves pathological alterations in the vertebral bone marrow known as Modic changes. These changes are visible on Magnetic Resonance Imaging (MRI) and indicate different stages of inflammation and degeneration near the damaged endplates.
Modic Type 1 changes represent an active inflammatory phase characterized by bone marrow edema, or swelling. This type is associated with a high degree of vascularity and is strongly correlated with acute and severe pain due to inflammation irritating the basivertebral nerve. Over time, Type 1 changes may progress to the more chronic Modic Type 2 changes.
Modic Type 2 changes involve the replacement of normal, blood-rich bone marrow with fatty tissue, a sign of long-standing degeneration. While often considered less acutely painful than Type 1, Type 2 changes still correlate strongly with chronic low back pain and significant endplate damage.
Identifying the Source of Pain
Diagnosing VLBP requires a systematic approach to confirm that the vertebral endplates are the specific source of the discomfort. The primary tool for this identification is a specialized MRI scan.
An MRI is used to visualize the characteristic Modic changes, which indicate inflammation or fatty degeneration adjacent to the endplates. The presence of Type 1 or Type 2 Modic changes in a patient with chronic, non-radiating low back pain strongly suggests a vertebrogenic etiology. This imaging finding helps doctors differentiate VLBP from other causes, such as pain arising from the discs or facet joints.
In some cases, a diagnostic basivertebral nerve block may be used to confirm the pain source. This procedure involves temporarily numbing the BVN with an anesthetic agent to see if it provides substantial, short-term relief from the patient’s typical pain. A positive response from this provocative test offers strong confirmation that the BVN is the primary pain generator.
Targeted Interventions for Relief
Traditional treatments for chronic low back pain, such as physical therapy, anti-inflammatory medications, and epidural injections, often provide limited or temporary relief for true VLBP. Because the pain is specifically linked to the basivertebral nerve, the most effective therapeutic approach targets this nerve directly. Basivertebral Nerve Ablation (BVA) is a minimally invasive procedure designed for this purpose.
BVA, sometimes referred to as the Intracept procedure, involves using radiofrequency energy to heat and neutralize the basivertebral nerve within the vertebral body. This technique stops the nerve from transmitting pain signals from the damaged endplates. The procedure is typically performed in an outpatient setting using a transpedicular approach, which involves entering the vertebral body through a small channel created in the pedicle.
Clinical studies have demonstrated that BVA can lead to reproducible and statistically significant improvements in pain reduction and functional ability for carefully selected patients with chronic VLBP. This specific intervention represents a targeted solution for a condition that has historically been resistant to conventional care.