Cervical Spondylolisthesis: Causes, Symptoms, and Treatment

Cervical spondylolisthesis occurs when one vertebra in the neck slips forward or backward relative to the one beneath it, and it is far more common than most people realize. A large population-based study found that roughly 6% of adults had anterior (forward) slippage and about 9–13% had posterior (backward) slippage, with rates climbing as people aged.¹ The condition ranges from an incidental finding on imaging that causes no trouble at all to a significant source of neck pain, nerve compression, and even spinal cord dysfunction.

Why Vertebrae Slip in the Neck

The most common driver is plain age-related wear. The facet joints, small paired joints at the back of each vertebra that guide neck movement, gradually break down over decades. A propensity-matched study comparing people with degenerative cervical spondylolisthesis at C4/5 to controls found that patients with slippage had more severe facet joint degeneration, flatter (more horizontal) facet joint angles, and worse paraspinal muscle quality, yet their disc degeneration was similar to that of controls.² That distinction matters because it challenges the common assumption that bulging or worn discs are the main culprit. Facet joint shape and the muscles supporting the spine seem to play a larger role in letting one vertebra slide over another.

Trauma is a less frequent but more dramatic cause. A severe neck injury can fracture the bony bridges (pedicles) that connect the front and back portions of a vertebra, allowing immediate slippage. One case report documented traumatic lower cervical spondylolisthesis from bilateral pedicle fractures, treated successfully with minimally invasive percutaneous screw fixation and confirmed healed at 18 months.³ Car accidents, falls, and sports collisions are typical mechanisms.

A third, sometimes overlooked cause is prior cervical surgery itself. When a laminectomy removes bone from the back of the spine to relieve pressure on the spinal cord, it can inadvertently destabilize the spine. One study of patients who had multilevel cervical laminectomy for myelopathy found that about a quarter developed instability at one or more levels.⁴ A separate long-term follow-up found that segmental instability after laminectomy occurred in roughly 18% of patients and was much more likely when preoperative lordosis (the natural inward curve of the neck) was already reduced.⁵

How Common Is It, and Who Gets It

The population-based study mentioned above, drawn from a general Japanese population, reported that posterior spondylolisthesis prevalence increased steadily with age in both men and women, with men affected more often.¹ These numbers suggest that many people walking around with no neck complaints at all have a small amount of vertebral slippage visible on imaging. The clinical question is never simply whether slippage exists but whether it is producing symptoms or threatening the spinal cord.

On that front, the same study found that posterior spondylolisthesis was an independent predictor of degenerative cervical myelopathy, with people who had it facing roughly four times the odds of developing spinal cord dysfunction compared to those without slippage.¹ A narrower spinal canal also raised the odds. In other words, slippage alone does not guarantee problems, but the combination of slippage plus an already-tight canal raises the stakes considerably.

What Symptoms to Expect

Many people with mild cervical spondylolisthesis feel nothing at all, and the condition only shows up when imaging is done for another reason. When symptoms do appear, they tend to follow a recognizable progression.

Neck pain is typically the first symptom. A study tracking patients with degenerative cervical spondylolisthesis found that neck pain was the initial complaint in every case, though it often faded into the background once neurological symptoms took over.⁶ The pain is often described as a deep ache at the base of the skull or across the back of the neck, sometimes spreading to the shoulders.

If the slippage narrows the opening where a nerve root exits the spine, the next stage is radiculopathy: pain, tingling, numbness, or weakness radiating down one arm, following the pattern of the compressed nerve.⁷ A systematic review of 102 patients with degenerative cervical spondylolisthesis found that about half had neck or occipital pain, roughly a quarter presented with radiculopathy, and nearly two-thirds had myelopathy or combined myelopathy and radiculopathy by the time they were evaluated.⁸

Myelopathy, spinal cord compression, is the most concerning presentation. It tends to develop gradually: clumsy hands, difficulty with buttons or handwriting, an unsteady gait, and a feeling of heaviness or stiffness in the legs. One research group studying myelopathy from degenerative spondylolisthesis found that spinal cord compression occurred paradoxically in neck extension (tilting the head back) rather than flexion, caused by the disc bulging and the ligamentum flavum buckling into the cord from behind.⁹ This is the opposite of what you might intuitively expect, since the vertebra slips forward most during flexion. The same study found that patients with spondylolisthesis had significantly reduced range of motion in the affected segments and a loss of the normal lordotic curve at those levels.⁹

How It Is Diagnosed

Cervical spondylolisthesis is typically graded by how far the vertebra has slid. A commonly used threshold defines spondylolisthesis as displacement of more than 2 mm, with Grade 1 being 2–3 mm and Grade 2 being greater than 3 mm.¹⁰ These numbers are small, and measuring them accurately requires the right imaging technique.

Standard lateral X-rays and MRI are the usual starting point, but they can miss the diagnosis. Because the slippage often increases with movement, static images taken in a neutral position may show a spine that looks stable. Lateral flexion-extension X-rays, where images are captured with the neck bent fully forward and fully back, can reveal instability that standard views miss entirely.¹¹ CT scanning adds detail about facet joint orientation and bony anatomy. One study of 101 spondylolisthesis patients used CT-based grading to classify slippage patterns and correlate them with facet joint orientation at the slipped level.¹²

If myelopathy or radiculopathy is suspected, MRI is essential because it shows the spinal cord and nerve roots directly. However, as noted in the myelopathy research above, the cord compression may be positional, so dynamic MRI or a combination of static MRI with flexion-extension X-rays gives the clearest picture.

Non-Surgical Treatment

For mild cases, particularly those involving only neck pain or modest radiculopathy, conservative treatment is the first step. This typically includes physical therapy to strengthen the deep neck muscles, gentle range-of-motion exercises, anti-inflammatory medications, and sometimes a soft cervical collar for short periods. Cervical traction, either mechanical or via specialized braces, can temporarily increase the space around compressed nerve roots and relieve radicular symptoms.

When radicular arm pain does not respond to physical therapy and oral medications, nerve root injections are an option. A retrospective study of fluoroscopically guided therapeutic selective nerve root blocks for cervical radicular pain found that about 60% of patients had a good or excellent outcome, with a significant reduction in pain scores and medication use at follow-up. About 30% of patients ultimately still needed surgery.¹³ Interestingly, a prospective randomized study comparing transforaminal steroid injections found no added benefit of the steroid itself over the local anesthetic alone, suggesting that the mechanical effect of the injection and the natural history of the condition may account for much of the improvement.¹⁴

Conservative treatment works best when the spondylolisthesis is low-grade, the spinal cord is not compressed, and symptoms are mainly pain rather than progressive neurological deficits. Once myelopathy appears, especially if it is worsening, the conversation shifts toward surgery.

Surgical Options

The surgical approach depends on where the compression is coming from and how many levels are involved.

For one- or two-level disease where the compression is mainly from the front (a bulging disc pushing into the cord or nerve root), the most established procedure is anterior cervical discectomy and fusion (ACDF). The surgeon removes the offending disc from the front of the neck, decompresses the nerve structures, and fuses the adjacent vertebrae together with a spacer and plate. A 10-year follow-up study comparing ACDF to cervical disc replacement (arthroplasty) for single-level disease found that both groups achieved satisfactory neurological improvement, with no significant difference in pain or disability scores between them.¹⁵ A systematic review and meta-analysis echoed this, concluding that there is no strong evidence favoring disc replacement over fusion at a single level, though arthroplasty preserves motion at the treated segment.¹⁶

When multiple levels need decompression, or when compression is primarily from behind, posterior approaches come into play. Laminectomy with fusion, using lateral mass screws and rods to stabilize the spine after the bone is removed, can address widespread cord compression while reducing the risk of the post-surgical instability discussed earlier.¹⁷ Laminoplasty, which hinges the lamina open rather than removing it entirely, is another posterior option that aims to preserve more of the spine’s natural anatomy. The choice between these techniques depends on whether the neck’s curvature (lordosis) is preserved, how many levels are involved, and whether instability is already present.

For traumatic spondylolisthesis without cord compression, minimally invasive posterior fixation with percutaneous pedicle screws can stabilize the fracture while sparing the surrounding muscles from the damage of a large open incision.³

Why Cervical Alignment Matters for Recovery

Surgeons increasingly pay attention not just to whether the cord is decompressed but to the overall alignment of the cervical spine after treatment. Two key measurements guide this: the C2–C7 sagittal vertical axis (SVA), which tracks how far forward the head sits relative to the lower cervical spine, and the mismatch between T1 slope and cervical lordosis (TS-CL). A meta-analysis of sagittal cervical parameters found that deviations beyond a C2–C7 SVA of about 40 mm or a TS-CL mismatch greater than roughly 15–20 degrees were associated with worse quality-of-life scores.¹⁸ Similarly, a study of symptomatic cervical spine patients found that both TS-CL and C2-C7 SVA were independent predictors of neck disability scores, even after adjusting for age.¹⁹

In practical terms, this means that simply removing the pressure on the cord without restoring good alignment can leave a patient with persistent neck pain and stiffness. If the head drifts too far forward of the trunk, the neck muscles have to work overtime to hold it up, which contributes to fatigue and pain. Surgical planning increasingly aims to correct alignment at the time of decompression, especially in multilevel cases.

Adjacent Segment Disease After Fusion

One long-term concern after any cervical fusion surgery is adjacent segment disease: accelerated wear at the spinal levels just above or below the fused area. When vertebrae are locked together, the segments next door absorb extra stress with every head turn and nod. A recent review found that patient age, pre-existing spinal degeneration, the type of instrumentation used, and how well alignment was corrected all influenced the risk of developing adjacent segment disease.²⁰ This is one of the theoretical arguments in favor of disc replacement over fusion at a single level: if you preserve motion at the treated segment, you might spare the neighbors. However, as noted earlier, the clinical data have not yet shown a clear long-term advantage for arthroplasty on this front.

For patients undergoing multilevel fusion, the risk is cumulative. The more levels fused, the more stress shifts to the remaining mobile segments. This does not mean fusion is the wrong choice when it is needed; it means that surgeons try to fuse only the levels that truly require it and to restore the best possible alignment so that the remaining segments share load evenly.

When Rheumatoid Arthritis Is Part of the Picture

Cervical instability is not always a degenerative or traumatic story. Rheumatoid arthritis (RA) deserves special mention because the inflammatory disease has a particular affinity for the upper cervical spine. A systematic review of cervical spine involvement in RA found that the prevalence of cervical disease in RA patients ranged from about 16% to 70%, depending on disease duration and severity, with atlantoaxial subluxation (slippage at the C1-C2 junction) being the most common abnormality.²¹

RA-driven cervical instability works through a different mechanism than degenerative spondylolisthesis. Instead of wear on the facet joints, the inflammatory process erodes the ligaments and bony structures that hold C1 and C2 together, allowing the top vertebra to slide forward on the one below. This can threaten the brainstem and upper spinal cord, making it potentially more dangerous than typical degenerative slippage lower in the neck. People with established RA, especially those with long-standing or poorly controlled disease, should have the cervical spine evaluated if they develop new-onset neck pain, electric-shock sensations with neck movement, or any of the myelopathy signs described earlier. Screening is especially important before general anesthesia, because intubation involves extending the neck, which can worsen atlantoaxial subluxation.