The Relationship Between Low Back Pain and Posture

Some people think that the reason you have lower back pain is that some part of your body is out of whack, imbalanced, or crooked.

The theory, which is widespread, is that your biomechanics (the position or movement of some part or parts of your body) cause your symptoms.

Maybe you sit or stand slouched like your spine is made of Silly Putty. That’s why you hurt.

Or maybe your hip flexors are too tight or hamstrings are inflexible or your abdominals are weak or your gluteal muscles are lazy.

Or maybe you have Upper Crossed Syndrome or Lower Crossed Syndrome.

Or maybe you have all of those things going on.

It makes some intuitive sense to conclude that if something is “malaligned” you could hurt from excessive pressure, tension or torsion – squishing, pulling or twisting.

But more likely, the unusual postures or movements are correlated with low back pain rather than a cause of it. These things often appear together so it’s easy to conclude, for example, a client’s super tight hip flexors must be the root of her complaint.

And as a clinician, you want or need something concrete to work with and abnormal biomechanics is that thing. If you can see or measure the problem, you have something to work on.

Something to fix.

And, after a few weeks of diligent work, the client feels better, and the measurements are better, well, you conclude it must have been the out-of-whack body.

I was giving a talk once and this issue came up, it always does, and an attendee interrupted me, almost yelling, “I know that when I see someone with a big, fat low back curve or their shoulder is way up higher than the other, I know that’s problem! So don’t tell me it doesn’t matter!”

Of course, I’m not saying biomechanics don’t matter (and I didn’t say it in the lecture either). When the force levels are high, position and movement influence how those forces are absorbed. So, yes, biomechanics has a role – more on this later.

But there are plenty of examples of people with less than ideal posture or movement who can function, some at a high level, without symptoms.

And the research on linking posture and lower back pain is weak at best.

• There’s no significant difference in the lumbar curve between men who have no back pain, moderate back pain or severe back pain.[source]
• Awkward positions in work environments are not more likely to cause back pain. [source]
• Just because one leg appears longer than the other doesn’t mean you’ll be more likely to have low back pain. [source]
• In people with and without back pain (600 subjects), there were no differences in several biomechanical factors including the lumbar curve, leg length difference, hamstring flexibility or iliopsoas flexibility. [source]

So, what do we do with this?

Well, abnormal, faulty, or whacky (however you want to describe it) biomechanics could be thought of as a risk factor. Kind of like how obesity is a risk factor for diabetes.

Obesity doesn’t cause diabetes but when it is present along with other factors, your chances of getting the disease go up.

Likewise, when something about your posture is out-of-whack enough combined with a high force, high speed or repetitive movement, your chances of developing low back pain go up.

But, do we ignore less than ideal biomechanics and just press on? Do we try to tweak your posture or movement to get you to line up with a pre-defined “ideal”? What if we can’t do that? What if your body is built in such a way that you just won’t ever have a “normal” position or movement? Are you destined to a lifetime of pain and trouble?

As with most things in life, the answer is not a clear black and white answer.

Let’s back up and look more closely at the assumption underlying the theory that abnormal biomechanics causes low back pain.

We’ll use a standing posture since this is a commonly assessed item. Let’s assume you have a larger than normal low back curve or lordosis and you have low back pain.

The lordosis is the curve in your lower back. This curve changes from standing to sitting to lying down. In other words, your lumbar curve is not a fixed curve. In the image below, you can see how the curve changes – gets bigger or smaller – based on how a person stands.

Example of lumbar lordosis

Because of this increased curve, the joints in your lower back could experience more pressure than a curve that is not so pronounced. The increased pressure could lead to pain much in the same way that leaning on a bent wrist for a long enough time will hurt.

So, the answer would be to reduce the curve, redistribute the pressure, and voila, you hurt less.

But, a “normal” lumbar curve can range from 20 to 60 degrees. So what seems like an increased lordosis may actually fall in the normal category. [source, source]

And, visual inspection – estimating the curve by just looking at you – is known to be poor between observers. [source] This means that if I look at a person’s low back and conclude that he or she has an increased lordosis, you will likely disagree.

To top it off, there’s a greater tendency for you to have a reduced lordosis if you have back pain. [source]

But, in some people, making postural changes or improving flexibility, for example, seems to reduce symptoms.

Most likely, here’s what’s happening.

We all have an inherent amount of strength – soft tissue, muscle, bone, ligament, tendon, cartilage, etc. Think of this more like your body’s bank account.

Some of us have an idea of how strong we are by how much weight we can lift, push, pull, carry, squat, throw, etc. The stronger you are, generally, the easier everyday life becomes. If you can squat 150lbs above your body weight, then taking a flight of stairs is unlikely to hurt.

When we encounter positions or activities, we take “withdrawals” from this physiologic bank account. We use some of the available strength (technically in the form of energy) to withstand the position or movement.

Rest replenishes the account.

After enough “withdrawals” though, you can become symptomatic. When the force demands exceed capacity enough, you’ll hurt.

If the “injury” is mild and you have some reserves in the “account”, you’ll recover more quickly than if the injury is more severe and your account is in the red.

If your physiologic bank account is somewhat low to start with, as it is after an injury, then your tolerance for certain positions or movements will be lower – you have less in the bank account to work with.

Coming back to high forces and biomechanics, the higher the force the less tolerance your body has as it uses a lot more of your bank account. So, optimizing the movement and position helps your body better adapt to those forces.

Keep in mind that what a pro athlete does for a warm-up might put another person in the hurt locker. “High force” is a relative term.

How To Improve

You can improve your situation though in a few ways.

One is by altering your position or movement just enough to decrease the size of the “withdrawal”. For low back pain, that might be using low back support when you sit. Or, maybe that’s improving your hip mobility to better distribute forces into your spine.

The second way is to increase your strength or, in a sense, make more deposits. This is not only muscle strength but especially other soft tissues like tendon, ligament, and cartilage (however, how you strengthen these tissues when injured is very different from how you address muscle weakness).

And another way is to decrease the withdrawals by altering your activity, position, or movement.

For example, an often-used method to treat lower back pain is the McKenzie Method.

In this system, the person with low back pain has to interrupt his or her activity to lie down on the floor and perform specific movements (this is also true of the Williams Flexion Exercises). The interruption of sitting, which is what most people do all day, is not insignificant.

By getting out of a sitting position, you decrease the “withdrawals” or the demand placed on the spine. And by doing a few movements, you add some “deposits”.

This happens in almost every type of active low back pain treatment method. Any method that asks you to alter your daily activity, perform certain exercises, stretches, or movements, is doing what I refer to as “pattern interruption”.

You reduce the physical demand by interrupting the typical activity, add movements or exercises to boost the “deposits” and the result is a relative increase in the “bank account” along with a reduction in symptoms.

Years ago, way more years than I would like to say, I focused mostly on biomechanics. I had assessment techniques that enabled me to measure almost any position and movement. I could define “normal”, identify unusual positions or movements, and create programs to address these problems.

Some of the treatment programs were quite elaborate and I felt good about how complicated everything was. If something is complicated and hard to understand, hard to use then you must be pretty smart and competent to use it , right?

And some people got better.

But as I studied and worked with this theory, I discovered that it’s almost impossible to change a person’s natural standing and movement in the short time people spent in rehab (As you get older, you learn how much you don’t know -hopefully – and why simpler is better.)

If you can change it, it usually takes a long time. You have to replace well established postural and movement habits with new ones. Think about how many people can’t keep a New Year’s resolution much less change the way they sit or stand.

And, oftentimes, when someone hurts, their position or movement is altered because of pain.

Eventually, I started thinking more about increasing capacity or strength first. It’s much easier and faster to improve a person’s strength since the majority of strength improvements in muscle and fascia come from learning. Your body figures out how to deliver more force faster.

I also realized that the best thing to do is to make the process as simple and as easy to understand as possible.

And, not surprisingly, as a person with low back pain gets stronger, movement improves, posture often improves, and pain decreases.

Most symptoms of lower back pain show up because of your inability to produce and/or absorb sufficient force and not because something is out of whack.

Having said that, I haven’t addressed the mental-emotional axis of pain which plays a large role in anyone who has had pain for more than about three months.

No, this doesn’t mean you’re faking it or making your symptoms up out of nothing.

What it means is that the mind controls all aspects of sensation and movement and something like worrying can increase your pain experience. So, keep that in mind as you search for answers about your own back pain.

It’s not all just physical.

But, that’s another article or three for another time.

Overcoming back pain, on the physical front, involves figuring out how to get stronger, even though you hurt, and doing that in such a way that you don’t get worse.

And that’s true for just about every other area of the body as well.

Thanks for reading.

If you like this article, why not share it with a friend? If you’re interested in coaching services, please contact my colleague Laurie Kertz Kelly for a free, 20-minute Strategy Session by, clicking here. To get my Secret Weapon to fight knee, hip & back pain and stiffness, subscribe for free today.

Doug Kelsey has been a physical therapist and human movement expert since 1981. He is formerly Associate Professor and Assistant Dean for Clinical Affairs at the University of Oklahoma Health Sciences Center and the author of several books. He has conducted over 250 educational seminars for therapists, trainers, physicians, and the public and has presented lectures at national and international scientific and professional conferences. His professional CV is here.