When we think of low back pain, an image immediately manifests itself; a slumped over, poor postured individual who has pain bending forward. This is correct in a lot of ways. But what if just as much low back pain came about from standing 'too' straight? Or holding too much of an erect posture? We don't associate low back pain with these kind of positions, we always assume it's a case of slumping, slouching and bending poorly. In terms of low back pain, it is imperative that we recognise both flexion based low back pain (slumping, bending, sitting pain), and extension based low back pain (pain with standing, arching back and lying flat). These two presentations are treated completely differently and need completely different, structured rehab programs. And so for today, we will enter the world of extension based low back pain.
What is it?
When we arch our lower backs, we go into a position called lumbar 'extension.' Lumbar extension is a fantastic way to unload our intervertebral discs of our spine, however the downfall of too much extension is that it has a tendency to cause facet joint compression. These joints are pushed together in extension, and when this happens for prolonged periods of time, we develop pain. Our paraspinal muscles of the lower back also activate more in extension and are prone to overuse in someone who has a natural tendency to stand, move, or exercise in extension.
Nb: Lumbar 'Lordosis'
What causes it?
We all have postural variations which are normal for ourselves. No posture is good or bad, and our best posture is our next posture; meaning we should be continually moving and changing, rather than staying static. At times though, our natural tendency to overextend our lumbar spine can be detrimental, causing pain. Dr Janda first talked about the contributing factors of extension based pain, outlining them succinctly with her explanation of 'lower crossed syndrome.' This theory has stood the test of time, and works relatively well most of the time, helping to explain why someone is in a position of overextension and pain.
To summarise, often one will have:
- Tight and overactive paraspinal muscles.
- Weak and underactive anterior core muscles.
- Tight and overactive hip flexor muscles.
- Weak and underactive gluteal muscles.
What types of injuries are associated with extension based back pain?
There are many different structures that could be causing the pain. They range from facet joint irritation, to muscular spasm. Commonly, a stress fracture or sponylisthesis will be caused from overextension, as can a spondylolisthesis. Spinal canal stenosis can be associated with extension as well.
How do I 'fix' it?
Most importantly, if it's not broke, don't fix it. If there is no pain associated with an overextended lumbar spine, then there is no need to worry about it. If low back pain is present, it would be worthwhile trialling some specific rehab exercises to help unload the structures being overloaded with the associated extension.
Some great examples are:
- Hip flexor stretching
- Paraspinal muscle stretching
- Anterior core strength work - resisting extension
- Gluteal strength work.
For specifics on any of the exercises, it's best to give the clinic a call to go through a structured rehab process.
That about wraps it up for today. I could talk about extension based back pain all day, and have a library of exercises to help, especially with strength, but for now, it's up to you to get onto it as soon as possible.