A Schmorl’s node, also known as an intravertebral disc herniation, is a common finding in the spine. It often represents a benign condition. These nodes are essentially protrusions of disc material into the bony vertebral body. While they can occur at any age, they are frequently discovered incidentally during medical imaging for other reasons.
What Are Schmorl’s Nodes
A Schmorl’s node forms when the soft, gel-like inner material of an intervertebral disc pushes through a weak spot in the endplate and into the adjacent vertebral bone. Intervertebral discs act as cushions between the bony vertebrae of the spine, absorbing shock and allowing flexibility. Each disc is anchored to the vertebrae by cartilaginous endplates, which are part of the vertebral body.
The disc material herniates vertically, either upward or downward, into the vertebral body, unlike typical disc herniations that extend sideways into the spinal canal. This creates a small indentation or cavity within the bone. Schmorl’s nodes are a common incidental finding on imaging. They can occur anywhere in the spine but are most frequently seen in the lower thoracic and lumbar regions.
Why Do Schmorl’s Nodes Form
The exact mechanisms behind the formation of Schmorl’s nodes are not fully understood, but several factors contribute to their development. One significant factor is trauma, particularly sudden, forceful compression of the spine, which may cause the disc material to push into a weakened endplate.
Degenerative changes in the spine, often associated with age-related wear and tear of the spinal discs and endplates, also play a role. As people age, the endplates can weaken, making them more susceptible to these protrusions. Some individuals may have a genetic predisposition to weaker endplates or disc structures. Underlying conditions that weaken bone, such as osteoporosis, or conditions affecting spinal development like Scheuermann’s disease, can also contribute to their formation.
Identifying Schmorl’s Nodes
Most Schmorl’s nodes do not cause any noticeable symptoms. They are often found during imaging studies performed for unrelated conditions. If symptoms do occur, they typically present as localized back pain, which might worsen with activity. This pain can stem from inflammation in the affected vertebral endplate or bone due to the disc material’s herniation.
Diagnosis of Schmorl’s nodes primarily relies on imaging studies. X-rays can sometimes detect these nodes, but Magnetic Resonance Imaging (MRI) provides the most detailed view of the disc and surrounding bony structures. CT scans can also be used to visualize these lesions. An MRI can reveal the characteristic protrusion of disc material into the vertebral body, often appearing as a notch or bump.
Living With Schmorl’s Nodes
Asymptomatic Schmorl’s nodes typically do not require specific treatment and are generally benign. When a Schmorl’s node does cause pain, conservative management strategies are typically the first approach.
These strategies may include over-the-counter pain relievers, such as nonsteroidal anti-inflammatory drugs (NSAIDs), to manage pain and inflammation. Physical therapy can help strengthen back muscles, improve posture, and alleviate discomfort. Applying heat or ice to the affected area can also provide relief. Activity modification, which involves avoiding movements that worsen the pain, is another important aspect of managing symptoms. Surgery is considered only in very rare instances, primarily if conservative treatments fail and severe, persistent pain or neurological symptoms are present.