If you recognize that question, you probably know this scenario: you’re sitting in a health care facility and, after telling your clinician about a pain in your back (or somewhere), they ask: how bad is it? 

As a pain physician, I always feel that the pain score (as it’s called) is a strange ritual. For one thing, a patient telling me they have “seven out of 10” gives me little to work with because while “seven” is a number, it isn’t an objective, replicable measure of pain. I ask patients to think of “10” as the worst pain they’ve ever felt or can imagine. But, as you might guess, because people's experiences and imaginations differ substantially, one patient might have a broken pinky, while another has a broken femur and both might (correctly and accurately from their perspective) report "seven out of ten" pain. 

If my job is to find and fix the cause of someone's pain, a pain score isn't helpful to me. Why, exactly, became more clear to me on a recent road trip, when I ended up at the Les Schwab Tire Center in Walla Walla, in Washington State's wine country.

Driving down Highway 12, I noticed a wvoooping sound coming from my Subaru’s back left side. Thinking a window or door was open, I pulled over and discovered that if I nudged the back left tire with my toe, the entire wheel wobbled. That seemed bad. I looked closer and noticed all the lug nuts were loose and that one nut and the stud behind it were missing entirely. So I jacked up the car, tightened the remaining four nuts and made my way to Les Schwab.

Leonel (a twentysomething mechanic whose starched white shirt was as crisp as his wit) listened carefully as I recounted the sound, my nudge test, diagnosis and field treatment. After pretending to be impressed by my mechanical skills, Leonel replied with a series of sensible questions:  when did it start (about 20 miles ago), had this ever happened before (no), when was the last time I’d had my tire looked at (about two weeks ago at Costco) and what I wanted to do (fix it). At no point did Leonel ask me how intense the sound was or the extent to which I felt the back left wheel pathology was affecting the rest of my Subaru or my life—on a scale of zero to 10. I suspect the idea never even crossed Leonel’s mind.

And why should it? My perception of the sound or the wheel pathology had no bearing on what Leonel was going to do. Leonel’s goal was to find and fix the problem.

After an hour or so, he called me back to his bay, where my Subaru was hoisted to eye level. A pathology report: he handed me the broken stud, used his pen light to show me where my wheel was damaged and explained why I needed to buy a new wheel.

Of course, back pain isn’t as straightforward as a tire problem. In my Subaru, the strange sound (a symptom) was a sure sign that something had gone wrong (damage). Yet many of my patients believe that because they have pain in their back, there must be damage in their back. In fact, the greater the intensity of their back pain, the more people are convinced that their back is damaged. Similar to what I expected of Leonel—my patients expect me to find and fix their back damage.

But back pain and back damage don’t necessarily go together. For example, a large-scale review showed that across 3,110 asymptomatic people, intervertebral disc degeneration was present in 27 percent of 20-year-olds ranging to 96 percent of 80-year-olds. Disc bulging was found in 30 percent of 20-year-olds to 84 percent of 80-year-olds. Yet none of these people reported any back pain.

Radiologists love this paper. When I order a lumbar MRI for a patient who has back pain, the radiologist often leaves me a brief note at the bottom of their report citing this study, suggesting that I should interpret the MRI results with “caution.” The radiologist is reminding me that an MRI doesn’t work like Leonel’s pen light—revealing at once the problem and how to fix it. Why? While back damage can certainly cause back pain, the presence of one doesn’t require the other. If someone can have back damage with no back pain, the pain they do have might be caused by something else.

What that “something else” is remains unclear, which puts me in a bind as a clinician because, like Leonel, to effectively fix a problem, I first must find it. This is where my training in psychiatry has proven helpful.

Depression and anxiety are markedly frequent among people with chronic pain: an analysis of 5,381 pain patients showed that a third had either depression or anxiety and that about half had both depression and anxiety. It could be that having back pain is depressing, but it could also be that depression can manifest as back pain or perhaps some types of depression and back pain share underlying causes. Patients insist I look at their back because that’s where it hurts. But, in some patients, I might be looking in the wrong place.

Consider that patients with chronic musculoskeletal pain who also have depression or anxiety aren’t typically helped by medications used to treat acute pain (e.g., opioids, NSAIDs), but many do respond well to medications that treat depression and anxiety. What this suggests is pretty obvious: depression and anxiety and pain all emerge from the brain and nervous system. So it makes sense that improving or restoring healthy brain function would improve a wide range of problems.

But how do I identify those patients? How could I more clearly define someone’s clinical problem to make my find-and-fix routine more effective?

There must be a better way to capture my patient's experience than "zero to 10." Such questions leave me feeling like I’m just kicking the tires on a much larger and complex problem.

This is an opinion and analysis article; the views expressed by the author or authors are not necessarily those of Scientific American.