Index
They are a protrusion that grows into the soft tissue of a spinal disc in the bony tissue of the adjacent vertebrae.
They are also known as Schmorl’s hernias or herniated discs and are especially common in patients who have previously suffered from minor degeneration of the spine.
Symptoms
They usually do not cause symptoms, but reflect that the wear on the spine has been produced over time.
When most hernias are associated with typical lumps, bulges, and extrusions that can put pressure on nerves and cause back pain and sciatica, this type of hernia breaks through the plate that covers the disc and goes directly to the bone.
In the late 1920s they were discovered by the pathologist Schmorl who described and studied them to determine their origin.
Growth place
They are typically found in the thoracic or lumbar spine just in the middle or lower back and are often not a major finding, as they are quite common.
Are they painful?
Not all of them are painful. But like the outer part of the disc, structural failure can cause the inner part of the disc to push in or through the outer part, which is commonly known as a herniated disc.
Ultimately, not all herniated discs are painful because not all can put pressure on a nerve or other sensitive structure, but the damage occurs to one degree or another.
In a Schmorl’s nodule, when the endplate cracks, some of the internal material from the disc nucleus breaks through the bone, like walking on a frozen pond and breaking your heel through ice and water seeping out.
Typically, the white area surrounding Schmorl’s node is the one that becomes inflamed and can cause pain, which is felt deep in the back and does not radiate down the legs like a typical herniated disc. It can be painful for a few years, and then eventually subside.
Painful Schmorl’s nodules cases
There are studies that indicate that Schmorl’s nodules that produce symptoms can be very painful and significantly affect the quality of life of the patient.
Damage to the end plate can cause a loss of pressure on the inner part of the disc and increased stress on the outer part, therefore, damage to the end plate can cause a series of mechanical and biochemical events that lead to degeneration and chronic back pain .
A node that has been chronic for a time, without inflammation and then modest changes occur around the node along with a typical herniated disc at that level, is highly suspicious for disc infection.
One pathway for bacteria to enter the disc is associated with hernias that extend part of the end plate. With a Schmorl nodule, there is already a path from the disc, through the end plate, and into the bone.
Any subsequent hernia, either from injury or age-related degeneration, can provide a direct connection, leaving the disc vulnerable to a rapidly progressing, pathological, deforming type of degeneration due to bacterial infection.
Even without infection, the inner part of the disc, when in contact with the blood supply within the bone, can cause a significant immune response that produces high levels of swelling.
Activating pain-producing chemicals called cytokines in the morning, getting better at noon, and getting worse again in the afternoon and evening.
If Schmorl’s node is not painful, it can produce symptoms if the nucleus keeps the hernia further in the bone marrow. Once the nucleus is in contact with the blood, an inflammatory immune reaction can lead to pain and further structural damage to the bone and disc.
Effects of Schmorl’s nodules
When performing follow-up imaging studies, most nodes are stable. However, some studies indicate that in about a year and a half, 26% will increase in size and about 13% will show type 1 changes in the area surrounding the nodule.
It is also indicated that these active hernias can increase the risk of vertebral fractures in 10% of cases.
Like medical changes, invasion of the bone marrow produces microfractures as the bone surrounding the marrow is destroyed.
Microfractures can produce deep, sharp pain and can increase inflammation.
Causes
Most can form after a heavy load incident or trauma that forces the nucleus to become part of the disc through the endplate rather than the outer part of the disc.
The outer part of the disc is normally more resistant to sudden forces than the end plate, especially in young individuals.
Gymnasts show a high level of Schmorl’s nodules, because when there is an injury that affects the spine in these upward and downward directions, these protrusions can occur.
Sometimes they show edema or a clear area around the nodule. Edema can resolve in as little as 6 months or it can persist for a few years.
In some cases, they are factors that can make the endplate and / or bone weaker and less resistant to structural failure, such as bone disease, degeneration, tumors, or disc infection .
Treatment for Schmorl’s nodules
An acute nodule that is symptomatic can be treated similarly to vertebral compression fractures.
Initial conservative measures often consist of pain and / or anti-inflammatory medications, bed rest, and lumbar support.
Heat and ice can be used accordingly and after the initial swelling has subsided, some find spinal traction devices beneficial.
Chiropractic adjustments and a strengthening of the supporting muscles through a good physical therapist can provide solutions.
However, if these conservative treatments fail, nerve blocks and percutaneous vertebroplasty or kyphoplasty may be considered for relief before fusion.
Despite these treatments, a small percentage of patients will have back pain that will not respond to typical therapies and will need to undergo an MRI scan that will indicate if there is a Schmorl’s nodule surrounded by bone inflammation.
In these cases, the treatment must be changed and the most effective option is vertebroplasty, especially when you encounter osteoporosis.
Studies on the use of this injection have reported that 80% of cases are successful.
