Practical Science on Movement and Pain
Practical Science on Movement and Pain
A few weeks ago I went back East to visit family. One of the highlights of the trip was going to the U.S. Open with my brother Eric to watch some tennis. When we were growing up together we spent most of our summers playing tennis, and usually capped them off with a trip to the U.S. Open. Good times. John McEnroe, Ivan Lendl, Boris Becker. For some reason my brother’s favorite player was Gene Mayer. Anyone remember Gene?
Anyway, my brother told me that his shoulder had been hurting for a few weeks and that he was considering going to the doctor to get an MRI. I immediately groaned and told him not to do that. I also called him a butthead. He said he wasn’t necessarily going to get surgery, but there was no harm in just finding out “what was going on inside the shoulder.”
I said “oh yes there is potential harm”, and then I reminded him that I actually write a blog about pain, which makes me kind of a big deal on the subject. He didn’t seem to care about that.
Fair enough. My brother knows better than anyone that I’m just “some guy.” But I wanted him to understand that many doctors, even a doctor in a white coat with MRI results in his hands, is just “some guy” too.
I have written before about how MRI results can be a very poor way to find the cause of chronic pain. And there is growing concern, backed by evidence, that MRIs are overused and can actually lead to worse outcomes than if they had not been done at all. Here’s the deal.
Many studies have shown that almost no matter where you point an MRI on a body, you can find something wrong there, even parts that are completely free of pain. Here’s a tour of the major joints as seen through the eyes of a magnetic resonance imaging machine.
In one famous study, MRIs were performed on subjects who did not have back pain. Fifty two percent of the subjects had at least one bulging disc or other MRI abnormality for which surgery is sometimes recommended. Given these findings, the authors stated that: “the discovery by MRI of bulges or protrusions in people with low back pain may frequently be coincidental.” In a similar study, MRIs on individuals who had never suffered from low back pain revealed that one third had a substantial spinal abnormality and 20% under the age of 60 had a herniated disc.
In a study of pain free hockey players, seventy percent were found to have abnormal pelvis or hip MRIs, and fifty four percent had labral tears. The author stated that “this study shows the limitations of depending too heavily on an MRI. A surgeon may see something in the image, but it isn’t causing a problem.”
In this study, researchers examined forty four volunteers, age 20-68, with no history of knee pain. Sixty percent showed abnormalities in at least three of the four regions of the knee, causing the authors to conclude that “meniscal degeneration or tears…are highly prevalent in asymptomatic individuals.”
In this study, researchers found that 23% of people with asymptomatic shoulders had a rotator cuff tear. They considered this percentage to be “astonishingly high” and concluded that “rotator cuff tears must to a certain extent be regarded as “normal” degenerative attrition, not necessarily causing pain and functional impairment.”
Here’s a study that looked at the shoulders of pain free overhead athletes, who are notorious for having their shoulders pretty much ripped to shreds. (BTW – My brother played four years of tennis at the University of Virginia and even played a little on the pro satellite tour in Spain. Not too shabby!) Researchers noted that 40% of dominant shoulders had findings consistent with partial or full thickness tears of the rotator cuff, as compared with 0% of the nondominant shoulders. But neither shoulder hurt and none of the athletes had any pain or problematic symptoms 5 years after the study.
OK, so MRIs don’t tell the whole story. But doctors must know this right? And a little information, even if it it’s not definitive, can’t hurt right?
That makes sense in theory, but in practice, it seems that many doctors often assign too much importance to abnormal findings on an MRI. There are several recent articles discussing this.
For example, here’s a quote from a New York Times article describing a troublesome dynamic associated with the use of MRIs:
. . . patients who are in pain often demand scans hoping to find out what is wrong, doctors are tempted to offer scans to those patients, and then, once a scan is done, it is common for doctors and patients to assume that any abnormalities found are the reason for the pain.
. . .
“A patient comes in because he’s in pain,” said Dr. Nelda Wray, a senior research scientist at the Methodist Institute for Technology in Houston. “We see something in a scan, and we assume causation. But we have no idea of the prevalence of the abnormality in routine populations.”
. . .
“Every time we get a new technology that provides insights into structures we didn’t encounter before, we end up saying, ‘Oh, my God, look at all those abnormalities.’ They might be dangerous,” said Dr. David Felson, a professor of medicine and epidemiology at Boston University Medical School. “Some are, some aren’t, but it ends up leading to a lot of care that’s unnecessary.”
In a separate NYT article, the authors discuss how many doctors, such as Dr. James Andrews, a well known sports medicine orthopedist, are taking a stand against what they perceive to be a massive overuse of MRIs. When Dr. Andrews scanned the shoulders of 31 healthy pain free professional baseball pitchers, he found abnormal shoulder cartilage in 90 percent of them and abnormal rotator cuff tendons in 87 percent. Dr. Andrews stated that: “If you want an excuse to operate on a pitcher’s throwing shoulder, just get an M.R.I.”
And there is now some research showing that the early use of an MRI as a diagnostic tool for back pain may make outcomes worse. In this study, it was found that MRIs were associated with increased likelihood of disability.
Why would that be? One possibility, as discussed above, is that misinterpretaiton of the meaning of an MRI can lead to unnecessary treatments such as surgeries. The other is that MRI results can act as a nocebo (the opposite of placebo) or otherwise create fear that makes pain and disability worse.
Pain is bascially an action signal that your brain creates to encourage you to fix a perceived danger in the body. The brain considers an enormous amount of information in deciding what constitutes a danger and what action is necessary, including the sensory data from the tissues, past memories, emotions such as fear, the availability of social and medical support, and future physical demands. And guess what, the brain will also consider whether some guy in a white coat tells you you have a bulging disc. That is likely to increase your pain.
Here’s a nice quote by pain researcher Lorimer Moseley, from his Ted Talk called Why Things Hurt, talking about why he hates to see doctors’ offices displaying those plastic spinal models that show a bulging red disc:
Any piece of credible evidence that they are in danger should change their pain … And they are all walking into a hospital department with models like this on the desk: … it messes with your brain. It cannot not mess with your brain.
The problem is that “finding out what is in going on the tissues” can really scare people about the condition of their body, which can make pain and disability worse. I have many clients who have been told that they have scoliosis, their knee is “bone on bone”, they have a bulging disc, or the “neck of an eighty year old.” Even though none of these facts have any real meaning, they make a very strong impression that becomes a permanent part of a person’s self image. It’s a lifelong nocebo. Thanks doc!
MRIs are obviously useful and sometimes completely necessary tools that can be used to accomplish a great many good things. But like any tool, they can be abused, and it seems that there is currently an epidemic of MRI abuse.
Keep that in mind Eric! And for crap’s sake just go get a massage, do some yoga, see if it helps. Butthead.