Who knew? There are really only 3 ways to to hurt my lower back. And I’ll bet the same goes for you. In this post I’ll give you an overview. And in subsequent posts we’ll dive a bit deeper into each of them. In this post we’ll cover why a “diagnosis” is often unhelpful. But first I’ll explain what those three ways are.
The 3 ways to hurt my lower back
This is not just conjecture. This is mechanically sound reasoning, demonstrated in the laboratory of Dr Stuart McGill of the University of Waterloo in Canada. Dr McGill has spent a long career examining living and dead tissue in the laboratory, testing it under different conditions of “load”, establishing what the mechanisms of damage are.
1. Peak Load
Put a sudden large load on a “tissue” (muscle, disc, tendon bone etc.). If that load is more than it can cope with at one time, it will fail/tear. Or part of it will tear/snap/break. That’s peak load. As far as your lower back is concerned, the load can either be exerted by you lifting something very heavy; that’s internal peak load. Or by being kicked/punched in the back (external load). Another version of internal peak load is sneezing. As a one-off load, if it’s too great and applied too suddenly, something’s going to give.
2. Sustained Load
If you exert a relatively modest force on a tissue for a prolonged period of time, eventually it’ll fail. Why do balloons spontaneously burst when they’ve been inflated for a while? When that moment of failure occurs will depend on three things.
- The health/strength of the tissue initially
- How big the load is
- For how long the load is exerted
A classic example here is sitting – if you spend hours sitting, that’s sustained load.
3. Cumulative Load
If you place the same load on the same tissue repeatedly it may fail too. Especially if you don’t give that tissue time to recover and adapt in-between loads. One of these days it’s going to tear. Arguably, degenerative change is due to cumulative load; lots of repeated loading without the tissue being given a chance to recover in between loads.
Why loading is more relevant than a diagnosis
Diagnoses are frequently wrong. And clinicians rarely agree. You could get 2 different diagnoses on the same day. So if you’re looking for a definitive diagnosis which explains why you have pain, it could be futile. Because that situation produces different symptoms in different people. Lots of people who have no lower back pain at all have disc prolapses, degenerative changes etc. You may have severe pain one day and be fine the next. How can that be? Because it’s unlikely that a day is enough time for a physical derangement in your back to suddenly heal. Getting a different diagnosis from different clinicians is unhelpful, and even stressful. And remember – stress aggravates pain.
The function of pain is to act as a warning system. If there’s sufficient loading for your nervous system to be concerned, it’ll give you a shot of pain. Fortunately, usually before you injure yourself. So, the next day you could be absolutely fine, so long as you didn’t actually damage the tissue.
It’s vital to work out what kind of loading has contributed to your back pain. Peak, sustained or cumulative, or any combination of them. We’ll look at each of them in more detail very soon.
But meantime, we’ve just covered the 3 ways to damage your lower back – peak, sustained and cumulative load. And the fact that knowing your mechanism of damage is more helpful than a formal diagnosis.