The bark of low back pain is usually much worse than its bite. The pain almost always makes it seem worse than it is.
MRI and x-ray for low back pain are surprisingly useless, because things like herniated discs aren’t actually that big a deal,1 most back pain goes away on its own,2 and trigger points (“muscle knots”) are common and can be alarmingly intense but aren’t dangerous. Most patients are much better off when they feel confident about these things. The power of justified, rational confidence is huge (see The Mind Game in Low Back Pain).
There are cases of low back pain that have alarming causes, but it’s rare. Once in a while back pain is a warning sign of cancer or an autoimmune disease. Or back pain could be associated with spinal cord damage. Or a few of other scary culprits.3 Over the age of 55, about one in twenty cases turns out to be a fracture, and one in a hundred is more ominous.4 The further you are from 55, the better your odds.
But how can you tell? It’s not always easy. This is a concise, readable guide to symptoms that need better-safe-than-sorry investigation with your doctor. (It’s basically just a plain English version of clinical guidelines for doctors.5) In other words, this article explains the difference between “dangerous” and “just painful” as clearly as possible. Tables, checklists, and examples ahead.
Back pain can suck the joy out of your days for week, months, even years. It can definitely be “serious” even when it’s not dangerous. I have worked with many truly miserable chronic low back pain patients, and of course the huge economic costs of back pain are cited practically anywhere the subject comes up. But your typical case of chronic low back pain, as nasty as it can be, has never killed anyone.
“Ominous” is medical jargon for “truly scary.” Cue Jaws theme music. Low back pain is ominous when it is caused by a spinal cord trauma, or a progressive disease that can maim or kill. Ominous causes of low back pain are rare, fortunately. But they are real. Awful things do happen, even the best doctors can miss them, and “alternative” health care professionals are even more likely to.
None of these are common. All of them usually cause serious symptoms that are easy to take seriously. Some of them can “fly under the radar” in early stages, but usually not for long. The names of the conditions link to carefully chosen articles from good sources.
|what is it?||major features|
|cancer||a tumor in or near the spine||Many kinds of cancer can cause many kinds of back pain, but some strong themes are: the pain grows steadily and is mostly unaffected by position and activity, worse with weight bearing and at night, and comes with other signs of being unwell.|
|cauda equina syndrome||pinching of the lowest part of the spinal cord||Hard to mistake for anything else: hard to pee, fecal incontinence, numb groin, weak legs. Caused by ruptured discs, trauma, cancer, infection.|
|spinal infection||infection in or near spinal structures||Hard to detect, often for a long time. Usually there’s a well-defined tender spot and then, eventually, deep constant pain, a rigid spine, sometimes fever and illness but not always.|
|abdominal aneurysm||ballooning of a large artery next to the spine||Pain may throb in sync with pulse. Mostly occcurs in people at risk of heart disease: older, heavier, hypertensive smokers and diabetes patients.|
|ankylosing spondylitis||inflammatory arthritis of spine and pelvis, mostly||Long term back pain starting well before middle age and progressing slowly and erratically, improves with activity but not rest, prolongued morning stiffness, possible involvement of other areas. More common in men.|
People understandably assume that the worst back pain is the scariest. In fact, pain intensity is a poor indicator of back pain ominousness,6 and some of the worst causes are actually the least painful (especially in the early stages). Pain intensity is a poor indicator of back pain ominousness & some of the worst causes are actually the least painful. For instance, someone could experience the symptoms of cauda equinae syndrome, and be in real danger of a serious and permanent injury to their spine, but have surprisingly little pain — even none at all in some cases!
Meanwhile, many non-dangerous problems can cause amazingly severe back pain. A muscle cramp is a good analogy — just think about how painful a Charley horse is! Regardless of what’s actually going on in there, muscle pain is probably the main thing that back pain patients are feeling. The phenomenon of trigger points — tiny muscle cramps, basically7 — could be the entire problem, or a complication that’s more painful and persistent than the original problem. It’s hard to overstate how painful trigger points can be, but they are not dangerous to anything but your comfort.
These two back pain scenarios might be medical emergencies. They do not necessarily mean something horrible is wrong, but it’s extremely important to make sure.
If you are experiencing true numbness10 around the groin and buttocks and/or failure of bladder or bowel control, please consider it a serious emergency — do not wait to see if it goes away. These symptoms indicate spinal cord injury or compression11 and require immediate medical attention. (Few people will have symptoms like this without having already decided it’s an emergency, but I have to cover all the bases here.)
And, of course, if you’ve had an accident with forces that may have been sufficient to fracture your spine, please seek thorough medical assessment promptly, including an X-ray to look for a fracture. You need an X-ray to ensure that your spine is not actually broken.
You shouldn’t worry about low back pain until three conditions have been met:
The presence of the big three does not confirm that something horrible is going on. It only means that you need to check carefully.
The story of actor Andy Whitfield is a disturbing and educational example of a case that met these conditions — for sure the first two, and probably the third as well if we knew the details. Whitfield was the star of the hit TV show Spartacus (which is worthwhile, but rated very, very R13) The first sign of the cancer that killed him in 2011 was steadily worsening back pain. It’s always hard to diagnose a cancer that starts this way, but Whitfield was in the middle of intense physical training to look the part of history’s most famous gladiator. Back pain didn’t seem unusual at first, and some other symptoms may have been obscured. Weight loss could have even seemed like a training victory at first. It was many long months before he was diagnosed — not until the back pain was severe and constant. A scan finally revealed a large tumour pressing against his spine.
Don’t confuse threat and risk. Working at the edge is a risk. But then again, so is walking out your front door.
“Red flags” are signs or symptoms that something medically ominous may be going on. A red flag is not a diagnosis. Red flags only indicate a need to look more closely. Check off all that apply … hopefully none or few or only the least alarming of them!
Some of these red flags are much less red than others, especially depending on the circumstances. For instance, “weight loss” is common and often the sign of successful diet! (Well, at least temporarily successful, anyway. ) Obviously, if you know of a harmless reason why you have a red flag symptom, it isn’t really a red flag (duh!). But every single actual red flag — in combination with severe low back pain that’s been going on for several weeks — is definitely a good reason to get yourself checked out.
Most people who check off an item or two will turn out not to have an ominous cause for their low back pain. But why not check?
Sorry I have to use the C word — I know it’s kind of a bummer. But C happens.
A few cancers in their early stages can be hard to tell apart from ordinary back pain — a bone cancer in the vertebrae, for instance — and these create a frustrating diagnostic problem. They are too rare for doctors to inflict cancer testing on every low back pain patient “just in case.” And yet the possibility cannot be dismissed, either! It’s an unsolveable problem.
Most cancers and ominous problems will inevitably start to cause other, distinctive, ominous symptoms, and it won’t be long before someone catches on that there’s more going on than just back pain. Being “freaked out” about persistent back pain poses a genuine threat: it can make low back pain much worse.So it truly is an extraordinary circumstance for back pain to be ominous without causing other symptoms that raise the alarm.
Meanwhile, it’s extremely common for non-life-threatening low back pain to be alarmingly severe and persistent — to have a loud bark! Your doctor may not appreciate how true this is, and may over-react to all persistent low back pain, even without other red flags. In most cases, you shouldn’t let them scare you. Being “freaked out” about persistent back pain is the real threat: it can make low back pain much worse, and much more likely to last even longer (a tragic irony).
This is an unholy combination of factors: the exact same symptoms can have either an extremely rare but serious cause, or an extremely common but “harmless” cause that can be greatly aggravated by excessive alarm!
The good news is that it’s easy enough to diagnose cancer if you look for it, so the answer to the dilemma is to simply do the testing when the time is right, but not before. There’s every reason to screen for cancer when the conditions merit it — that is, when the red flags appear in combination with persistent, severe pain.
Pain on the right side of the back is not particularly worrisome, no. Same with the left. There are two main kinds of back pain that occurs only on one side:
Most of the anatomy of the low back and abdomen is symmetrical. Some of the guts are not symmetrical, and only some of those are plausible causes of right-sided back pain. Here’s some of the key anatomy to consider:
By now you should be getting the idea that there the side of the pain on its own doesn’t tell us much, and most of the one-sided sources of pain are viscera that usually cause more abdominal pain. In other words, the only reason to worry about right or left lower back pain is if it is otherwise worrisome: if you have other significant non-back symptoms, or red flags from the lists earlier in this article.
I am a science writer, former massage therapist, and assistant editor of ScienceBasedMedicine.org. I have had my share of injuries and pain challenges as a runner and ultimate player. My wife and I live in downtown Vancouver, Canada. See my full bio and qualifications, or my blog, Writerly. You might run into me on Facebook and Google, but mostly Twitter.
Wednesday, February 24, 2016 — Added a bunch of further reading suggestions.
Wednesday, January 13, 2016 — Added a substantial new section about left and right low back pain.
Monday, January 11, 2016 — More editing, more! Added some better information about pain being a poor indicator, and the role of myofascial trigger points. This article has become extremely busy in the last couple months — about 4,000 readers per day, as described here — so I am really polishing it and making sure that it’s the best possible answer to people’s fears about back pain.
Wednesday, January 6, 2016 — Added table of worst possible causes of back pain. Miscellaneous editing and organizing.
Wednesday, May 8, 2013 — More editing and minor improvements. Added the barking dog image. Made the article more “shareable,” with new metadata for social media sites.
Tuesday, February 19, 2013 — Edits and miscellaneous minor improvements. Added one red flag.
Saturday, April 16, 2011 — Added some clarification about the position of symptoms of cauda equina syndrome, and a personal footnote related to that scary scenario.
Monday, October 12, 2009 — Added important and reassuring information about the chronicity of low back pain. See “Prognosis for patients with chronic low back pain: inception cohort study”.
Wednesday, July 8, 2009 — Publication.
This Australian study concluded that “prognosis is moderately optimistic for patients with chronic low back pain,” contradicting the common fear that any low back pain that lasts longer than 6-9 weeks will become a long-term chronic problem. This evidence is the first of its kind, a rarity in low back pain research, a field where almost everything has been studied to death. “Many studies provide good evidence for the prognosis of acute low back pain,” the authors explain. “Relatively few provide good evidence for the prognosis of chronic low back pain.”
Their research differs from past studies of chronic low back pain, which tended to focus on patients who already had a well-established track record of long-term problems (in other words, the people who had already drawn the short straw before they were selected for study, and are likely to carry right on feeling rotten). Instead they studied new cases of chronic low back pain, and found that “more than one third” recovered within nine more months. This evidence is a great foundation for more substantive and lasting reassurance for low back pain patients.BACK TO TEXT
In the vast majority of patients with low back pain, symptoms can be attributed to nonspecific mechanical factors. However, in a much smaller percentage of patients, the cause of back pain may be something more serious, such as cancer, cauda equina syndrome, spinal infection, spinal compression fractures, spinal stress fractures, ankylosing spondylitis, or aneurysm.BACK TO TEXT
Marvelously progressive, concise, and cogent guidelines for physicians on the treatment of low back pain. These guidelines almost entirely “get it right” in my opinion, and are completely consistent with recommendations I’ve been making for years on PainScience.com. They are particularly to be praised for strongly discouraging physicians from ordering imaging tests only “for patients with low back pain when severe or progressive neurologic deficits are present or when serious underlying conditions are suspected.”BACK TO TEXT