Sunday, September 2, 2012

Anterior Pelvic Tilt (A Paradox, A Question, Some Possible Answers)

In this post I will cover anterior pelvic tilt, back pain, why your tight hamstrings may be trying to save you, why trying to counteract pelvic tilt with strength exercises may not work, open scissor posture and how the diaphragm could be the culprit. But first, the question.

Why do some people have excessive anterior pelvic tilt and lordosis when standing but when then go into 4-point kneeling quadruped they are able to get their spine into neutral, and sometimes when they lay on their back the spine is nearly flat? But when you return to standing they can't tilt their pelvis, they can't achieve a neutral position, they are locked in anterior tilt and hyper-lordosis.

If it was a structural issue they wouldn't be able to tilt their pelvis in 4-point kneeling and the back wouldn't go flat in supine. If it is a 'tight' muscle, why is that muscle not tight when they are on the floor?

I have observed this over and over again. As a background, I deal with a lot of people with lower back pain, but not all the people I have observed this in have back pain, but most do. I also see this mainly in women, again, mainly because I probably see more women with back pain and in classes, but also I just don't see this anterior pelvic tilt in many men.

But first things first.

What is anterior pelvic tilt?

Pelvis rotates down and forward, lower back becomes 'excessively' curved
If we consider a level pelvis to be neutral, then if it tilts down and forward it is no longer neutral, anterior pelvic tilt (APT), if it tilts the other way the pelvis has gone posteriorly and the lower back can end up flat. You can also get a paradoxical lumbar curve without the pelvis moving, the curve goes the wrong way, I have observed this in men, according to Pavel Kolar (prague school, www.rehabps.com, Dynamic Neuromuscular Stablization -DNS) this is caused by hip dysplasia. (I will say no more about this).

A couple of things to consider:

  1. If the anterior pelvic tilt isn't accompanied by any back pain or movement restriction is it really a problem?
  2. Some people have genetics that pre-dispose them to APT, this is most commonly seen in sprinters, therefore it may have an advantage for certain movements. Also be careful when looking at sprinters and some people, it may look like they have excessive APT or lumbar curve due to the size of their glutes. The glutes give the illusion of a large lumbar curve, but when you look at the lumbar spine in isolation it is  'neutral'.
What causes APT & hyper-lordosis?

As stated above it could genetics. Two other obvious scenarios: if someone is 8 months pregnant or is carrying an extra 2 stone on their gut then the reason for the APT are obvious and no amount of 'corrective' movement or breathing will make a difference.

In the women I mainly observe this in it could due to several reasons

  1. Cultural: stick out your bum, push out your chest and suck your abs in to exaggerate your attributes!
  2. Lifestyle: women wearing high heels, changes the whole kinetic chain, weight is shifted forward at the foot and everything above compensates. To be fair to the women I have observed this in aren't always big high heel wearers.
  3. A compensation or protective mechanism: If flexion is painful then the body compensates by going into extension to spare the spine and avoid the pain. But why does it go so far into extension, if neutral is also pain free?
All these can result in the classic Janda lower crossed syndrome - tight erector spinae, weak abdominals, weak glutes and tight hip flexors. However, why aren't the erector spinae tight when laying down, they can easily do a knee hug stretch, and some clients can even do core work in supine with a neutral spine, but in the plank or press up position they typically drop back into hyper-lordosis.

In standing, the pelvis tilting down can also be accompanied by the ribs going up or flaring. This results in something that the DNS folks call open scissor posture, and the point where the scissors are pivoting and where the most pressure is occurring is typically in the lumbar spine.

Open scissors posture: the front of the scissors is the pelvis and ribs moving away from each other. The pivot point is in the lumbar spine - ouch!

Toe Touches and Hip Hinging

Using the SFMA there are four scenarios, they can touch their toes (multi segmental flexion in the SFMA parlance) and it is either painful or not, they cannot touch their toes and it is painful or not painful.

The painful scenario is most obvious, flexion causes pain, they are forward flexion intolerant and are avoiding flexion because it hurts. I don't actually see the painful scenario that much in the APT clients, more typical is they can't touch their toes and it is not painful or you ask them to touch their toes and they put their hands on the floor - they are mobile...too mobile.

To the hip hinge, there are three scenarios I see

  1. They do the hip hinge, and the APT corrects itself into a normal lordosis, this doesn't happened that often, however much you coach
  2. They go into even more hyper-lordosis, with the lordosis extending up into their thoracic spine. Typically see this with the mobile Yoga types
  3. As soon as they hinge, their lumbar spine goes into flexion and rounds. They have the hip mobility of a breeze block. Therefore, they need to increase hip mobility, but not in the hip hinge position standing, because they just don't get it in this position. In this case taking them to the floor and doing a rocking squat could be a starting point, with the hips unloaded, and in this position their body doesn't have to worry about the ankle and all the other joints trying to keep them upright.
Glutes

You can try to get the person with APT to squeeze their glutes. I normally demonstrate this, as when I squeeze my glutes my pelvis tilts in quite a big way. Normally 2 things happen when they try to squeeze their glutes

  1. Nothing happens, they squeeze but there is no glute contraction. If they have back pain or hip pain the glute may be inhibited, they have glute amnesia (listen to audio lecture with McGill and Liebenson where McGill states they have now proved this in the lab, www.movementlectures.com )
  2. The glutes contract but the pelvis doesn't move, the APT is not being caused by the glutes not working.
All the standing glute work in the world trying to strengthen these muscles doesn't work in these cases. RDLs and Good Mornings and all that don't do anything,the glutes don't fire, or they do fire and the APT remains. And the client still has APT, excessive lordosis and is still moving through their lumbar spine.

Take the person into a supine 2 leg bridge, but be careful, at the top of extension you can see their lumbar spine actually going into more lordosis with no glute involvement. And at the start of the movement, watch, their lumbar spine flattens, they have gone into posterior pelvic tilt, but check, the glutes may still not be working. They can get into PPT in supine with no glute activation.

To really isolate the glute action here, try the one leg glute bridge aka cook hip lift. This is humbling for many people, hug one knee in and then bridge up, see how far they get with no lumbar spine help.

There are quite a few videos on youtube showing the cook hip lift, here is one 

Tight Hamstrings?

Typically if the person can't touch their toes they tend to think they have tight hamstrings.

However, in nearly every client I can think of, as soon as you lay them on their back and get them to do a straight leg raise (ASLR in the FMS) they can easily achieve 70 degrees, and most women are getting 90 degrees. And if they have 70 degrees or less, they nearly always get more range of movement with simple passive help. This shows two things, when their hamstrings are unloaded in a supine position they show normal range of movement, and if it can be passively increased immediately could it be something on the front of the thigh that doesn't have the strength to life the leg up.

I find people want to stretch their hamstrings for 4 reasons

  1. Someone told them their hamstrings were tight, like a physio
  2. They can't touch their toes - see above why in most cases the hamstrings are not short
  3. They actually feel tight all the time
  4. They want to stretch because they like it, they are good at it, and everyone has always told them more flexibility is a good thing
In the back pain client the tight hamstrings may actually be protecting them. If someone has lower back pain and finds forward flexion painful then

"If the hamstrings are tight and short they effectively prevent pelvic tilting." (Chaitow et al, 2002)
 and

"In this respect, an increase in hamstring tension might well be part of a defensive arthrokinematic reflex mechanism of the body to diminish spinal load." (Vleeming et al, 1997 quoted in Chaitow, 2002)
 So the tight hamstrings are preventing movement that may cause pain. I would personally say that the hamstrings are actually contracting all the time rather than being 'tight'. And if they have normal ROM supine then they definitely aren't tight, your body is doing what it can to protect your spine when you stand up, if it has no other option it uses the hamstrings. These people also typically get hamstring cramping in a glute bridge.

Extension, Centration and The Mind

Normally when I ask a person with APT to lean back in standing (multi segmental extension) they can do it and there is no pain, and all sorts of McKenzie extension positions don't make any difference to pain in those with back pain (pain could stay the same, go away, get worse, or not be a problem on that particular day). On that note, it is surprising the amount of back pain patients who have had facet joint injections when extension doesn't hurt but flexion does.

If we take the person to half kneeling hip flexor stretch position we have taken out any influence from the ankle and knee joint. In this position, it is quite normal to see the hip not extending properly, the glute not firing and the lower back going into more lordosis and increasing APT, as well as the person feeling a big stretch on the front of the thigh. Is the lower back compensating for lack of hip extension?

Also, it is important to note that the person in APT doesn't feel like they are in APT, they feel normal. In the case of forward flexion back pain, has the body gone into extension to avoid pain and over compensated. Even with or without pain, has the body decided this is the default postural position, it believes it is centred. It could be compensating for head forward posture or ankle restriction or a whole host of things in the chain, but it thinks this is normal. To use Weingroff core pendulum analogy, the pendulum had swung into flexion, so the body overreacted and swung the pendulum too far into extension.

But this is only happening in a loaded position, note that when the spine isn't being loaded by gravity in standing it can go back to neutral. The brain is in control. The person has what Kolar and the DNS guys would call 'body blindness'. In the movement system Feldenkrais they talk about a Homunculus in your mind, a little version of you in space, your body has an image of where you are in space, and it may not match reality, you need to reset the system.

In the standing loaded position.

"internal forces developed by our own muscle are often more detrimental than external forces..external forces are decisive in what way external forces apply on our system." (DNS course notes)
You get told to strengthen your core or back or posterior chain, but strengthen what? In standing we're making the position worse, we need to take the person into unloaded positions or more 'primitive' postures if you will. If we change the function we may be able to change the structure (Lewit, Kolar) with the right exercise.

Its not a strength issue or a muscle issue, its a motor control issue. Having said that, there might be one muscle you need to work on first.

The Diaphragm and a possible answer


  
Breathing is the fitness concept de-jour at the moment, and I will cover it in more detail in another post. However, I think we need to explain exactly why breathing and the diaphragm is so important, especially when it comes to back pain. Firstly the diaphragm actually attaches to the lumbar spine and ribs, as well as many other structures and muscles in the abdomen and thorax (Chaitow, 2002), so it would seem we should train it like the other core muscles. Secondly, "the lower back is stabilised via intra abdominal pressure" (DNS notes). The diaphragm pushing down when you breathe in and helps to stabilise the spine. And in people with lower back pain this may be lost.

Nearly all the people who I have seen with APT and/or lower back pain demonstrate paradoxical breathing, which means their diaphragm and ribs move up when they breath in during normal relaxed breathing. When it should move down when they breathe in.


In a study by Kolar et al (2012, JOSPT) they scanned the diaphragms of people without back pain and compare them with those who had had chronic back pain for 6 months. In the MRI scanner, they did three things, 1) lay down normal breathing 2) then got the person to do isometric flexion of an arm 2) then isometric flexion of a leg.



(I have taken the image below from the paper, before anyone sues me, it is available on the internet for free). On the left is the diaphragm movement during normal breathing of a non painful subject, image B is the movement of the diaphragm in a person with chronic back pain.

Source: Kolar et al, JOSPT, vol 42, no.4, rehabps.com

But the key point is shown in the graph below, when the person is relaxed there isn't much difference between the back pain and non pain people, but as soon as the back pain people have to apply resistance the diaphragm shoots up, it becomes higher in the thorax and the amount it is moving is a lot less than in the non painful subjects.

Source: Kolar et al, 2012, JOSPT, vol 42 no 4. rehabps.com for full article
During strenous activity the breathing pattern in a person with back pain is altered. In a cross sectional view the front and middle of the diaphragm doesn't get recruited but the back part does, this basically pulls the spinal column up and forward causing shear forces which may make back pain worse. Also with the diaphragm higher you can surmise that intra abdominal pressure is lower and the spine is not as stable.

And this may cause the back to be unstable. Of course, there is always the possibility that the back pain caused this dysfunction and not the other way around.

"One possibility is the lack of postural diaphragmatic activation is substituted by excessive activation of the superficial lumbar paraspinal muscles, which may lead to hypertrophy and, eventually, result in lumbar hyperlordosis and/or anterior pelvic tilt. Future research should study this mechanism as possibly contributing to or even underlying the etiology of low back pain symptoms." (Kolar et al 2012:360)

Breathing incorrectly may cause the muscles in the back to become over-developed, until you addres the breathing issue those erector spinae may continue to be rock hard and switched on.

So the first port of call to resolve APT and back pain may well be breathing correctly. See the video below from Evan Osar (though he doesn't mention it all in the video this is essentially the DNS method, he does mention DNS and Kolar a fair amount in his book). This video basically covers what I woudl consider the first thing to do with someone who had APT and back pain. Note the three dimensional nature of the breathing. You will find that many Yoga disciples can easily breathe forward into their abdomen, but they will find it difficult to breathe into their back, which can really help stabilise the spine, relax the lower back and get the area into a more neutral position; all with nothing more than breathing. Simple, but easily missed in our rush to load up with weights.





In Summary

Hopefully this post has raised a few questions and given a few answers.

  • Firstly, trying to correct posture in standing with standard strength exercises may never work. You need to unload the system and reset it. And ask yourself why you are correcting it in the first place
  • The muscles just do what the brain tells them to do. The movements don't have to be complicated, they should be simple and slow to begin with, and can be quite high repetitions (15-20 reps, re-learn the motor pattern) This could be the DNS approach or a movement system like Feldenkrais or whatever exercises you find work best for you.
  • Start with breathing, the diaphragm influences spine position and stability
  • Free up muscles that are over- working, for example, 6-10 repetitions of the cat camel are proven to reduce viscosity of the muscles either side of the spine. Then progress to endurance and strength exercises like the bird dog.
  • You could then move onto more strength type moves, but stay in these more primitive positions to begin with, could be kneeling rocking squats, then cook hip lifts as well.
  • Half kneeling hip flexor stretch with core braced and back in neutral may be appropriate if your movement assessment highlights an issue.
  • The hamstrings are probably not tight and don't need stretching, they need to switch off, but they will only do that once other muscles are doing the job for them
  • The details matter
  • Breathing exercises can even be done in between sets of strength exercises, integrate into the training program
  • If somethings worth doing, do it everyday, I think Dan John said that.
The End at last

References

Chaitow L et al (2002) Multidisciplinary Approaches to Breathing Pattern Disorders. Churchill Livingstone
Kolar et at (2012) Postural Function of the Diaphragm in Persons With and Without Chronic Low Back Pain. Journal of Orthopaedic and Sports Physical Therapy. Vol 42, no 4
McGill & Liebenson From the Lab to the Trenches www.movementlectures.com
www.rehabps.com



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