What Is Mild Retrolisthesis and How Is It Treated?

Retrolisthesis on a scan report means one bone of the spine sits slightly behind the one beneath it, and “mild” means the shift is small. For most people that makes it a finding to understand rather than an emergency, and treatment usually starts with exercise and pain control, not surgery.¹ A backward slip also may not be simple damage. It can be one way the spine adjusts as posture changes with age.²

What Your Scan Report Is Describing

Retrolisthesis is a backward slip; a forward slip is called anterolisthesis, and your report may use spondylolisthesis as the general term for either. The shift is measured in millimetres, from the back edge of one vertebra to the back edge of the one below. In one group of older adults with neck problems, shifts under 2 mm were classed as mild, 2 to 3.4 mm moderate and 3.5 mm or more severe.³ Cutoffs vary between doctors and between the neck and lower back, so ask what yours used.

The line on your report names the level, such as L4-L5 or C4-C5, meaning the bones above and below the slip. Words like “grade 1” or “mild” point to a small slip. The slip is often listed next to disc degeneration or arthritis, but those are separate observations. Your doctor’s interpretation matters more than the label alone.

Backward slips are common at the lowest lumbar level, L5-S1. About 23% of people having surgery for a herniated disc there had one.⁴ In the neck, slips in older adults cluster at the C3/4 and C4/5 levels.⁵ Retrolisthesis is seen in every age group and becomes gradually more common with age.⁶

The millimetre figure depends on which images were measured and where the lines were drawn, so a single number is best treated as an approximate snapshot. A slightly different figure on a follow-up scan does not by itself mean the slip has changed.

Each type of scan shows different things. An X-ray shows bone outlines well, so it is the simplest way to see one vertebra sitting behind another. A CT gives a more detailed picture of the bones and is often used when surgery is being considered. An MRI shows discs, nerves and the spinal canal, which is why it is often the scan ordered for pain, and the one where a slip turns up by chance.

Is It Causing Your Pain

As the upper back rounds and the body leans forward with age, a backward slip may shift the body’s centre of gravity back to keep balance.⁷ People with retrolisthesis tend to have a flatter lower back curve, and the slip may compensate when the pelvis can’t tilt enough.⁸⁹¹⁰

Many people picture a slipped bone as about to slide out of place. A mild slip is usually stable, though bending or standing X-rays are needed to check that. Pain levels depend more on nerves and discs than on the millimetres of shift.

In people with a herniated disc at L5-S1, having a retrolisthesis did not mean worse pain or function.¹¹ In the same group, the slip was not linked to more disc wear or arthritis.¹² So a mild slip found alongside other problems is often not the main source of pain.

Scans of people with no pain at all often show disc wear, arthritis and small slips, so an abnormal-looking scan does not prove that finding is the source of symptoms. Clinicians try to match the scan with your symptoms and examination before blaming any one finding. If your pain doesn’t match the level of the slip, a nearby disc or joint may be the better explanation.

Your own pain pattern helps here. Pain felt mainly in the back, which may spread to the buttocks, usually points to the joints, discs and muscles of the spine. Pain that travels past the knee or into the hand, sometimes with tingling, points more toward nerve irritation, a separate problem from the slip itself. Describing when it hurts, where it travels and what eases it is often more useful to your clinician than the scan wording.

Numbness or weakness running down a leg or arm suggests a pinched nerve. Leg pain and heaviness when walking that eases on sitting can signal narrowing of the spinal canal. Report these symptoms, and seek urgent care for loss of bladder or bowel control.

Tests Your Doctor May Order

The usual test is a pair of X-rays taken while bending forward and backward, often listed as flexion-extension X-rays.¹³ You stand sideways to the plate, bend forward, then lean back. Each image takes seconds and needs no preparation.

Bending X-rays can miss movement. Comparing a standing X-ray with a lying-down MRI picked up slipping in about 61% of people with lumbar slips, versus about 21% with bending X-rays.¹⁴ X-rays taken while sitting slumped, compared with CT or MRI, caught about 8 in 10 slips that worsened, versus about 6 in 10 with standard side X-rays.¹⁵

The two positions can differ because standing loads the spine, so a loosely held vertebra can sit further back than it does lying down. An MRI is done lying down, which can make a slip look smaller or even hide it. When comparing reports, ask whether each image was taken standing or lying.

If the slip barely changes between bending forward and leaning back, it is described as stable, which supports non-surgical care. If it moves noticeably, your clinician may look more closely, especially if you have leg symptoms or are considering surgery. Pain can limit how far you bend, which is one reason movement gets missed, so tell the technician what you can manage. Movement between images can steer a surgeon toward fusion, and how much a slip moved between standing and lying predicted how much back and leg pain improved after fusion surgery.¹⁶

Non-Surgical Treatment

Non-surgical care should be the first step for most degenerative slips, with or without nerve symptoms.¹⁷ Options include pain relievers and anti-inflammatories like ibuprofen, bracing, and flexion strengthening exercises.¹⁸ Physical therapy, steroid injections and pain medicines are reasonable for low-grade slips with leg pain.¹⁹ Anti-inflammatories help during flare-ups but carry stomach and kidney risks, so short courses discussed with your doctor are typical.

A physical therapy program starts with an assessment of your posture, strength and which movements hurt. You then begin with gentle activation of the deep abdominal and back muscles and progress from there. Home exercises most days for several weeks are typical. Flexion exercises that curl the trunk often feel better than arching.

Core stabilization exercises that train deep trunk muscles improved disability in people with low-grade slips when used alone.²⁰ They did not clearly reduce pain.²¹ Expect gains in what you can do before pain eases.

A brace or support belt limits bending and can reduce pain during flare-ups. Wearing one all day for long periods can leave trunk muscles weaker, so it is generally used for short periods or particular activities, while exercises build your own muscle support.

Epidural steroid injections place anti-inflammatory medicine near irritated nerves. Relief can be partial or short-lived; in one reported case it lasted only days.²² Keeping the spine aligned when sitting, standing and lifting can reduce lower back strain.²³

Improvement is often gradual, with fewer bad days and better tolerance for walking or sitting before pain disappears. If symptoms get worse, or new leg weakness appears, go back to your clinician rather than waiting out the full course.

Chiropractic and Spinal Manipulation

Forceful manipulation should be avoided for unstable or high-grade slips.²⁴ Cautious manipulation is not ruled out for low-grade slips without nerve deficits.²⁵ In one reported case, extension traction and manipulation reduced several lumbar backward slips with lasting pain relief over 13 months.²⁶ Gentle flexion-distraction tables are marketed to widen the canal and ease disc pressure.²⁷ Single case reports cannot show that most people will see slips reverse.

Chiropractors, physical therapists and osteopaths may all use hands-on techniques, but their training and methods differ. Spinal manipulation usually means a quick, controlled thrust that can produce a popping sound, and the sound is not a measure of success. Mobilisation is gentler, with slow, repeated movements, and is often chosen when a slip is present.

Before booking, ask whether they have reviewed your imaging and stability results, and whether they use gentle techniques rather than high-force thrusts. Ask what should happen if numbness or weakness appears, and how many visits they would do before reassessing.

New numbness, tingling or weakness in a leg or arm after treatment should be reported straight away. Pain that is clearly worse and doesn’t settle within a day or two is a reason to stop and be re-examined. Loss of bladder or bowel control, or numbness in the groin area, needs urgent medical care, not another appointment.

When Surgery Comes Up

About 90 to 95% of spinal canal narrowing can be treated by removing pressure on nerves without fusion.²⁸ Fusion is reserved for the roughly 5 to 10% of cases with clear instability before surgery.²⁹ Surgery may be discussed after months of leg pain despite therapy and injections, weakness that is getting worse, walking limited by leg symptoms, or movement on imaging tied to symptoms.

Decompression means the surgeon removes bone or thickened tissue pressing on the nerves so they have more room. The goal is mainly to relieve leg or arm symptoms, so it often helps those more than back pain. Because no hardware is placed, recovery is usually quicker than after fusion, though it varies by person.

Fusion joins two or more vertebrae so they heal into one piece, using screws and rods together with bone graft. The aim is to stop movement at a level that has been shown to be unstable. Recovery is longer than for decompression alone, and the fused level no longer bends.

Fusion stiffens a level, so neighbouring levels move more and can wear faster.³⁰ A backward slip can develop there, more likely with thin discs, more disc wear and weaker back muscles.³¹ Fusion also carries higher complication risks in older adults.³²

Useful questions for a surgeon: Is decompression alone an option? How was instability shown? What does recovery look like in weeks? How could fusion affect nearby levels?

Will It Get Worse

Backward slips often reflect slow posture change rather than sudden damage.³³ Forward lean of the upper body is linked to them.³⁴ Exercises that support upright posture and trunk strength are a reasonable focus. Related slips are more common over age 50, in women and in people with loose joints.³⁵

A slip that formed gradually often settles into a stable position as the discs and joints stiffen with age. The surrounding muscles and ligaments help hold the spine, so a stable mild slip may remain unchanged for years. Repeat imaging is usually only needed if symptoms change.

Regular walking keeps the muscles around the spine working, and strengthening the abdominal, back and hip muscles supports it in daily posture. A healthy weight reduces load on the lower back. Avoiding long stretches of slumped sitting takes strain off the discs.