When Back Pain Isn't Just Back Pain: Red Flags Every PT Should Know

I've been practicing physical therapy for over 15 years, and I've probably evaluated a few thousand people with back pain in that time. The vast majority, we're talking 95%+, have mechanical issues. Muscle strains, disc problems, facet joint irritation, postural dysfunction. Things that respond well to PT.

But there's that other 5%. And those cases keep me up at night.

Early in my career, I missed one. Or rather, I didn't miss it exactly, I had a feeling something was off, but I didn't push hard enough. The patient eventually got the right diagnosis, but it took longer than it should have. That experience changed how I practice.

I'm writing this for two audiences: other clinicians who might benefit from a reminder about vigilance, and patients who need to understand when their pain warrants more investigation than a course of physical therapy.

The Problem with Pattern Recognition

Here's what happens when you see back pain every day: you get really good at recognizing patterns. Guy in his 40s, hurt his back lifting something heavy, pain worse with bending forward, probably a disc. Woman in her 60s, stiff in the morning, pain with extension, likely facet arthritis.

Pattern recognition is incredibly useful. It's also dangerous.

Because when you see the same thing day after day, it's easy to assume the next person fits the same pattern. And usually they do. But not always.

I've learned to ask myself with every new evaluation: "What am I missing? What would make this NOT just another mechanical back pain case?"

Red Flags I Actually Screen For

There are standard red flag questions every PT learns in school. But honestly, the way they're taught, as a checklist you run through during the initial eval, doesn't capture how this actually works in practice.

Here's what makes me concerned:

Age and onset:

• First episode of significant back pain after age 50 with no clear mechanism
• Gradual onset that's progressively worsening over weeks or months
• Pain that started after seemingly minor or no trauma

Pain behavior:

• Severe night pain that wakes them up (not just uncomfortable sleeping, but actually waking from pain)
• Constant, unrelenting pain that doesn't change with position
• Pain that's getting progressively worse despite appropriate treatment
• Pain completely out of proportion to mechanism of injury

Associated symptoms:

• Unexplained weight loss (more than 10 pounds without trying)
• Fever or night sweats
• History of cancer, especially breast, prostate, lung, kidney, or thyroid
• Recent infection
• Immunosuppression or prolonged steroid use
• Bowel/bladder changes or saddle numbness (cauda equina, this is an emergency)

Response to treatment:

• No improvement whatsoever after 2-3 weeks of appropriate PT
• Getting worse despite treatment that should be helping
• Pain pattern doesn't make mechanical sense

None of these alone necessarily means something sinister. But combinations of them? That's when my antenna goes up.

The Cases That Stick With You

I'm not going to share patient stories, that's not appropriate, and these are real people dealing with serious health issues, not teaching examples.

But I will say that I've had a handful of patients over the years where I've had to say, "I think you need imaging before we continue treatment," or "I'm not comfortable treating you until we rule out other causes."

Sometimes I'm wrong and it turns out to be mechanical after all. That's fine, I'd rather be overcautious than miss something serious.

And a few times, my concerns were validated. Those are the cases that remind me why this vigilance matters.

The Tricky Part About Early Metastatic Disease

Here's something they don't really prepare you for in PT school: early metastatic disease to the spine can look a lot like mechanical back pain.

Someone with a history of breast cancer five years ago comes in with mid-back pain. It's tender to palpation over the thoracic spine. Hurts with certain movements. They're 55 years old, otherwise healthy.

Is it mechanical? Maybe. Could it be metastatic recurrence? Also maybe.

The safe call is imaging. But in our healthcare system, that's not always straightforward. Insurance might push back. The primary care doc might want to try conservative treatment first. The patient might be hesitant about radiation exposure or cost.

This is where clinical judgment and advocacy come in. If I'm concerned enough, I need to be clear and direct: "I think we need to rule out other causes before treating this as a mechanical problem."

Sometimes that conversation is uncomfortable. But it's necessary.

For Patients: When to Push for More Answers

Most back pain is benign and will improve with time, activity modification, and appropriate exercise. That's actually good news.

But you should advocate for further evaluation if:

• Your pain is severe and unrelenting, not relieved by any position
• You're waking up at night from pain (not just uncomfortable, but actual waking)
• You've lost weight without trying
• You have a history of cancer
• Your pain is progressively worsening over weeks despite appropriate treatment
• You have fever, chills, or feel systemically unwell
• You have new bowel/bladder problems or numbness in the groin area

If your PT or doctor is dismissive of these concerns, find someone who will listen. Trust your instincts, you know your body.

The Balance Between Vigilance and Reassurance

Here's the challenging part: I don't want to create unnecessary anxiety. The overwhelming majority of back pain is mechanical and responds well to conservative treatment.

If you're reading this and now worried that your back pain might be cancer, it's probably not. Serious pathology is rare.

But rare doesn't mean never. And the consequences of missing it are significant.

So the balance is: be informed, be aware of red flags, but don't catastrophize every ache and pain.

For clinicians, the balance is similar: maintain appropriate vigilance without becoming so paranoid that you're ordering MRIs for everyone.

Clinical judgment is knowing when to treat and when to refer. That judgment comes from experience, but also from staying humble enough to question your assumptions.

What I Tell New Grads

When I precept PT students or mentor new clinicians, I tell them this:

"Most of what you see will be straightforward. But stay curious. Ask yourself what you might be missing. Don't let pattern recognition make you complacent. And if something doesn't feel right, even if you can't quite articulate why, pause and reconsider."

The diagnostic process isn't just about checking boxes on a red flag list. It's about listening to patients, trusting your clinical intuition, and being willing to say "I'm not sure" when appropriate.

The Bottom Line

Physical therapy is incredibly effective for most musculoskeletal pain. But we're not just treating pain, we're screening for serious pathology and making appropriate referrals when necessary.

That's part of being a good clinician. Knowing what we can treat, and just as importantly, knowing when to refer out.

For patients: most pain is benign. But if your pain has concerning features or isn't responding to appropriate treatment, advocate for further evaluation. You're not being difficult, you're being smart.

For clinicians: stay vigilant. Trust your instincts. And when in doubt, refer.

The vast majority of the time, everything will be fine. But the times when it's not? Those are the cases that matter most.

Experiencing persistent pain that's not improving with treatment?
At Spectrum Therapeutics of NJ, we take a thorough approach to evaluation and won't hesitate to refer for further testing when appropriate.

Spectrum Therapeutics of NJ
601 Hamburg Turnpike, Suite 103
Wayne, NJ 07470

Phone: (973) 689-7123
Email: spectrum@spectrumtherapynj.com
Web: spectrumtherapynj.com

Good physical therapy includes knowing when you need more than physical therapy.