Why You Probably Don't Need an MRI for Low Back Pain

When patients arrive at our Burlington clinic with low back pain, one of the most common requests we hear is, "Can you send me for an MRI?" The instinct makes sense. If something hurts, you want to see what's wrong. But for most low back pain, an MRI doesn't actually answer the question — and it often makes things worse.

What MRIs are actually good at

MRIs are essential for a specific subset of cases: suspected fractures, infections, tumours, severe nerve compression with progressive neurological loss, and pre-surgical planning. If your case has any of those red flags, imaging is the right call.

For routine low back pain, though, MRIs are overused. The image looks impressive, but the findings often don't match the pain.

The problem: pain-free people have abnormal MRIs too

Two decades of research is clear on this. If you took 100 middle-aged adults with no back pain at all and put them through an MRI scanner, here's roughly what you'd find:

• About 35 with disc bulges
• About 18 with disc protrusions
• About 8 with disc herniations
• Many more with degenerative changes, arthritis, and "abnormal" findings

Over 60% of pain-free adults have something on their MRI that would be flagged as abnormal. So when you have back pain and an MRI shows a herniation, the herniation may or may not be causing the pain. Often it's been there for years.

Why this matters for your care

Once a structural finding shows up on a scan, the conversation tends to escalate. Patients (and clinicians) start considering injections, prolonged rest, and even surgery — sometimes for findings that were never the actual driver of pain.

Most low back pain is functional. It comes from things that don't show up on imaging at all: tight or inhibited muscles, restricted joint motion, poor movement patterns, and ligaments under more stress than they should carry. None of those are visible on an MRI.

What works better

A thorough movement-based assessment finds the actual driver. Once we identify it — usually some combination of mobility limits, strength imbalances, and movement patterns that overload the back — we can address it directly.

Functional causes of back pain respond well to conservative care: physiotherapy, chiropractic, and targeted exercise. Most patients improve substantially without any imaging at all.

When you should get imaging

Imaging is appropriate if you have:

• Recent significant trauma
• Progressive weakness or numbness
• Bowel or bladder changes (this is urgent — go to the ER)
• Unexplained weight loss with back pain
• History of cancer with new back pain
• Pain that's clearly not improving with conservative care after a reasonable trial

If none of those apply, imaging probably isn't going to change the treatment plan. A proper assessment will.