While we don’t have a complete understanding of the etiology of idiopathic scoliosis, there is supporting evidence for an association between spondylolisthesis and the development of scoliosis, especially in the spine’s lumbar region. Keep reading to explore the association further.
Spondylolisthesis is a condition of spinal instability caused by one of the spine’s bones (vertebrae) slipping out of place. When the vertebrae move more than they should, a vertebra can slip out of alignment onto the bone below, introducing adverse pressure, and this can result in pinched nerves known to cause lower back and leg pain.
The human spine is made up of small bones called vertebrae. They are stacked on top of one another and are separated by intervertebral discs. When a vertebra suffers damage or is displaced, the effects can be felt throughout the spine. Before we move on to the specifics of spondylolisthesis, let’s touch on some basic spinal anatomy.
The Spine’s Structure
The structure of the spine is based on the function and health of its individual parts and bones called ‘vertebrae’. As mentioned, the vertebral bodies are stacked on top of one another, and the position and function of the vertebrae give the spine its natural alignment and curves.
The spine’s natural curvatures give it its strength, flexibility, and allow it to evenly distribute the mechanical stress incurred through movement.
The spine gives us balance, support, and allows us to maintain a straight upright posture. When there is an issue with a vertebra moving too much and slipping out of place, this starts to change the spine’s structure as the individual vertebra’s movement triggers effects that can be felt in other areas of the spine.
There are three main sections to the spine: cervical (neck), thoracic (middle back), and lumbar (lower back). Each section has a characteristic curvature, and when there is vertebral damage, movement, and/or slippage, the related spinal section’s curvature is compromised.
When the spine experiences a loss of its healthy curves, the body responds by putting in bad curves, and this affects the overall biomechanics of the spine.
There are a number of conditions that affect the vertebrae of the spine, and one such condition is spondylolisthesis.
What is Spondylolisthesis?
Spondylolisthesis is a condition of spinal instability because there is more movement of the vertebral bodies than there should be; this results in a vertebra slipping out of alignment with the rest of the spine.
The affected vertebra will press down against the next, introducing adverse pressure and tension on the vertebral body below. This can cause pinched nerves, which can lead to back pain and radiate pain into the legs.
The resulting misalignment weakens the spine, and while we don’t fully understand the etimology of idiopathic scoliosis, there is a significant amount of supporting evidence for the connection between spondylolisthesis and the development of abnormal sideways spinal curvatures.
While spondylolisthesis can develop higher up the spine, it most commonly occurs in the lumbar section, and this weakening of the lower spine contributes to the development of lumbar scoliosis.
Before we move on to the connection between spondylolisthesis and scoliosis, let’s take a look at some of the characteristics of spondylolisthesis: cause, symptoms, and treatment.
What Causes Spondylolisthesis?
As spondylolisthesis has several known causes, medical professionals have developed a 6-point classification system that addresses these different causes.
Type l: this form of the condition is also known as ‘congenital spondylolisthesis’, and this means people are born with it.
Congenital spondylolisthesis is caused by a defect in the vertebra’s articular processes (the part that controls the vertebral body’s movement).
This malformation usually happens in the lumbosacral junction, where the lumbar spine meets the sacrum (bone that connects the lumbar spine to the pelvis).
The defect in the area results in the last vertebra of the lumbar spine slipping forward over the sacrum.
Type ll: type II spondylolisthesis is also called ‘isthmic spondylolisthesis’ and is the most common type.
In this form, there is an issue with a particular section of a vertebra known as the ‘pars interarticularis’.
This form is further classified as Type ll A, B, or C and references the different vertebral damage that causes the condition to develop. These types commonly affect weightlifters, gymnasts, or people who have experienced trauma to the spine caused by an accident.
Overuse, hyperextension, and/or injury can lead to full or micro-fractures of the pars, and this can cause the affected vertebra to slip forward and out of alignment with the rest of the spine.
Type lll: as is the case with many other spinal conditions, the degenerative effects of aging can also be the cause of spondylolisthesis type III onset.
The intervertebral discs that cushion the vertebrae are commonly affected by aging. They can lose water and proteoglycan (the gel-like substance within). If this occurs, the discs can become flatter, providing less cushioning, and making them less able to handle shock and distribute mechanical stress throughout the spine.
When this happens, the facet joints of the vertebral bodies are brought closer together and are unable to effectively control movement.
As a result, the vertebrae become hypermobile, eventually leading to the forward-slip of a vertebral body; this is most common in women 50+ years of age.
Type lV: type IV spondylolisthesis is similar to a form of type II as it commonly involves a fracture; the difference is that the fracture involves the facet joints, rather than the pars interarticularis.
When there is a fracture of a vertebra’s facet joint, the vertebral body’s front is separated from its back portion, causing it to easily slip forward and out of alignment with the rest of the spine.
Type V: type V spondylolisthesis is not as common as it’s caused by tumors pressing on the vertebrae and weakening them, which can lead to fractures splitting the vertebrae, potential slippage, and spinal instability.
Type VI: type IV spondylolisthesis is also known as ‘iatrogenic spondylolisthesis’, and the vertebral slippage is caused by an impairment of the parts that has been weakened by surgery.
So to summarize, spondylolisthesis can be caused by a birth defect, fractures, a defective pars interarticularis, degeneration due to overuse, strain, or age, tumors, or back surgery.
Now that we understand the many different potential causes of spondylolisthesis, let’s move on to exploring symptoms of the condition.
Spondylolisthesis Symptoms
People with spondylolisthesis can experience multiple symptoms, or none at all, depending on several factors such as age, cause, and severity level.
Common symptoms include:
- Back pain
- Feelings of stiffness in the back
- Tight leg muscles
- Sciatica pain
- The development of abnormal spinal curvatures
While the aforementioned symptoms can range in severity with some people not experiencing any noticeable symptoms, it’s always important to treat spinal conditions proactively; this prevents them from causing further damage or worsening as a person faces further age-related degenerative changes.
Treatment for Spondylolisthesis
When it comes to treating spondylolisthesis, there are two main approaches to choose between: traditional and functional.
A traditional approach would include a more general response of prescribing pain medications for those struggling with back and/or sciatica pain, steroid injections to reduce inflammation, alternating heat and/or ice application, and spinal-fusion surgery.
There is, however, another approach, a functional one, that is less invasive, more proactive, and actually addresses the underlying structural nature of the condition.
Here at the Scoliosis Reduction Center®, if one of our patient’s spondylolisthesis has caused a scoliotic curve to develop, first and foremost, we address the cause of the spondylolisthesis.
In fact, studies have shown that up to 48 percent of children with spondylolisthesis develop at least 5 degrees of scoliosis.
Once the cause of the spondylolisthesis is addressed accordingly, we move on to addressing the abnormal spinal curvature (scoliosis) that has developed as a result.
To do this, we combine multiple scoliosis-specific disciples such as chiropractic, therapy, rehabilitation, and corrective bracing.
We would customize a treatment plan that best addresses the individual characteristics of the patient and their condition, and we would integrate these treatment disciplines so they would complement each other and produce the best possible results.
We would work towards restoring as much of the spine’s healthy curves as possible, improving the strength and function of the spine, and achieving a curvature reduction.
Additional reading: What Is Multilevel Spondylosis?
What Exactly is the Connection Between Spondylolisthesis and Scoliosis?
Now, we know that in the most common form of scoliosis, adolescent idiopathic scoliosis (AIS), we don’t fully understand what causes it to develop.
We know that there are certain factors such as gender, familial prevalence, bone formation issues, and vestibular-system abnormalities that are thought to play a role, but we have yet to isolate one single-known cause.
Another theory on the etiology of idiopathic scoliosis is that spinal instability due to another source, such as spondylolisthesis, could be a factor, especially in the development of lumbar scoliosis (the most common site of spondylolisthesis).
This theory suggests that lumbar scoliosis can develop as the result of a ‘mechanical foundation issue’ of the lumbosacral junction.
As scoliosis involves a lot of uneven forces and results in an overall asymmetrical effect on the body, perhaps a condition that predisposes the spine to asymmetrical tendencies, as is the case when one of the spine’s lowest vertebrae slip forward, can lead to the development of scoliosis.
The increased incidence of scoliosis in people with spondylolisthesis has been well supported and documented.
Conclusion
The spine is extremely important for human anatomy. It helps us balance, bend, twist, and engage in a variety of movements. It also helps us stay upright and maintain good posture.
When a spinal condition develops, its effects can be felt throughout the body. This is because the spine also plays a role in facilitating communication between the brain and the rest of the body.
The spine is made up of individual bones called vertebrae, and the way these vertebrae connect and engage with each other and other parts of the spine dictate its overall health and function.
When something happens that compromises the spine’s stability, a number of issues can emerge.
Spondylolisthesis is a spinal condition that causes instability as a vertebral defect, injury, strain, degeneration, or tumors cause a vertebra to slip forward; this displacement affects the spine’s alignment and biomechanics as there is a shift that will be felt throughout.
Once that vertebra slips, that instability can cause scoliosis to develop in the area, most commonly the lumbar section of the spine.
Regardless of the initial cause, once a scoliotic curve develops, here at the Scoliosis Reduction Center®, we can help limit the fall out by working towards a curvature reduction, strengthening and stabilizing the spine, and restoring as much of the spine’s healthy curves as possible.
