Anterolisthesis is a spinal disorder characterized by a dislocation of at least one vertebra relative to another. It occurs when an upper vertebral body, the main part of a vertebra, slips forward relative to the vertebra below. As it moves out of position, it can pinch the spinal nerves connected to the vertebrae involved in the displacement, and also potentially damage the spinal cord. This condition is graded by severity on the basis of how far forward a vertebra has slipped.
Fractures are the most common reason for anterolisthesis, although there can be other causes as well. This condition is most commonly observed with the fourth and fifth lumbar vertebrae, although it can arise in other regions of the spine. Patients can experience a variety of symptoms, depending on the location and severity of the anterolisthesis. Some common signs are numbness, tingling, abnormal sensations, loss of bowel or bladder control, pain in the spine or in the region innervated by the involved nerves, and difficulty controlling the legs.
Medical imaging studies are used to visualize the spine. The displaced vertebrae will be clearly visible in the images and a physician can measure to determine the degree of displacement. This will be taken into account, along with the results of a patient interview, when developing a treatment plan. If the patient has a history of spinal injuries or other problems, a doctor may feel that conservative treatment will not be enough to address the problem.
Conservative treatments for anterolisthesis consist of rest and gentle physical therapy. The patient may be put on bed rest to allow the spine to recover without strain and the healing process can be extended. If the injury is severe, a doctor may recommend skipping this treatment and proceeding to surgical options such as spinal fusion, where the displaced vertebra will be moved back into place and fused to a neighbor to hold it in alignment. Spinal surgery will fix the abnormal positioning of the vertebrae although it can come with serious risks including the risk of infection or permanent nerve damage.
When diagnosed with anterolisthesis, patients may find it helpful to ask about the available treatments and to get information about the risks and benefits of each. The doctor can also discuss possible recovery time and other issues that may be important for the patient to know about. Patients should be aware that while surgery can reposition the vertebrae, symptoms like pain and neurological problems can sometimes persist.
What Causes Anterolisthesis?
There are six main contributing factors for anterolisthesis: aging, traumatic injuries, repetitive stress fractures, congenital spinal problems, degenerative diseases and surgical side effects. Some people are more at risk for the condition than others.
Blunt Force Impacts and Injuries
One of the most common causes of anterolisthesis is a traumatic injury. Sudden, strong impacts can move vertebrae out of alignment and into an abnormal position. Several situations can lead to this type of injury:
- Car accidents
- Impacts from football, lacrosse basketball and other team sports
- Slips and falls
- Workplace accidents
- Impacts from falling objects
Severe trauma can go so far as to fracture a vertebra, causing it to slip out of place. Fractured vertebrae are weaker, so they’re more likely to have problems with anterolisthesis in the future.
Repetitive Trauma Injuries
Athletes can experience problems with anterolisthesis due to small but repetitive injuries to vertebrae. Young people are especially vulnerable to this type of damage because the spinal column and bones of the body are still in development. Here are some sports that can weaken vertebrae gradually:
These sports activities require athletes to stretch past comfortable limits, overextending their arms, legs or entire body. If the extreme movements continue, they can cause damage to the vertebrae and spinal alignment.
Age-Related Changes to the Spine
As people age, the cartilage of the spine loses water, gets thinner and becomes more vulnerable to damage. In this situation, cartilage doesn’t cushion vertebrae properly. Instead of a snug fit that holds bones firmly in place, vertebrae become “loose” and can slip out of place more easily. When this happens, seemingly minor injuries to the lower back that wouldn’t have caused problems before can now cause anterolisthesis.
While less common, sometimes anterolisthesis is caused by a degenerative disease:
Any disease that weakens the structure of bones or cartilage increases the chance of vertebrae moving out of place. Tumors can contribute to anterolisthesis if they increase in size. As they grow, they push vertebrae into incorrect positions.
Congenital Problems and Inherited Risk Factors
Some children are born with a misaligned spinal column. This condition puts them at risk for anterolisthesis later on. Scientists aren’t completely sure why some babies have this problem.
There are also inherited risk factors that can make certain people more likely to experience spinal issues as adults. They may have weaker vertebrae that are simply more prone to stress fractures or slippage.
Surgery can sometimes leave individual vertebra more vulnerable to slippage. At times, this is due to a medical error, and other times it’s merely a side effect of the type of surgery needed. If doctors have to remove a piece of bone or change its shape, the vertebrae may not fit together as closely as before.
What Is the Difference Between Anterolisthesis and Spondylolisthesis?
When one of your spinal vertebrae slips out of place, this is known as spondylolisthesis. Depending on the direction the vertebra moves, doctors sometimes refer to the condition by different names. When a vertebra slides forward, it’s called anterolisthesis. If a vertebra moves backward, the condition is referred to as retrolisthesis.
The symptoms are virtually identical in all cases. You can say that anterolisthesis and retrolisthesis are both types of spondylolisthesis.
Is Anterolisthesis Serious?
Anterolisthesis affects everyone differently. The degree it affects your life depends on the symptoms you’re experiencing, how intense they are and the original cause of spinal problems. Some people experience severe pain that makes it hard for them to work or care for children. Other people hardly notice any symptoms at all.
The good news is that the outlook for people who have anterolisthesis is very positive. Depending on the extent of slippage, recovery may only require physical therapy and exercises to strengthen your lower back muscles.
Surgery is generally used as a last resort. Many patients respond well to surgery, resuming their day-to-day activities in a few months. Surgery can prevent vertebrae from slipping in the future.
When Should Visit a Doctor for Anterolisthesis?
If you think you may have anterolisthesis, you should schedule an appointment with your doctor right away. This condition won't disappear on its own. The sooner you receive treatment, the sooner you can experience relief. Prompt treatment may prevent the condition from getting worse.
In rare situations, the nerve roots of the lower back can become compressed. This is a dangerous complication that can lead to paralysis. If you ever have trouble feeling your legs after an accident, call 911 immediately.