Wednesday, 28 June 2017

About Pain

The Pain System #4 - Some more of the science

"Stress biology is concerned with the physiological mechanisms and behavioural strategies that enable organisms to survive or maintain homeostasis” “Pains prime adaptive purpose is to powerfully motivate the organism to alter behaviour in order to aid recovery and survive” 

(Gifford 1998)

This blog is an appendix to the previous three blogs on pain response and sensitisation. It is intended to give some more detailed background on how the brain in particular manages pain.

Part 1: How our Tissue Responds to Pain

Part 2: Amplifying Pain - Central Sensitisation

Pain 3: Shark Attack, It's all in the Mind

The basic function of pain is:

  • To protect you.
  • To alert you to danger - often before you are injured or badly hurt.
  • To makes you move and think differently
  • VITAL for healing

Pain is a normal response to what your brain judges to be a threatening situation.

The basic pain mechanism involves
Input / stimulus (the nerve endings in tissue) => process and evaluate (the spinal cord and brain) => output / response (the whole body). “We need a system that is able to monitor health of organisms own body and provide appropriate recovery response if damage occurs” (Gifford 1) Is Pain is all in your mind? Well, yes. The following areas of the brain are involved in evaluating pain inputs and formulating responses:
  • area for organising and preparing movement.
  • area for concentration and focus.
  • area for problem solving and memory.
  • fear, fear conditioning and addiction area.
  • sensory discrimination area.
  • area for stress response, autonomic regulation and motivation.
  • movement and cognition area.

Following a potentially painful stimuli the evaluation and response also involves many different systems of the body:
  1. The Sympathetic nervous system - this increases heart rate, mobilises energy stores ready for movement and releases adrenaline into the body.
  2. The Motor (muscle) system is very important e.g. remove limb from flame, limp, run away, hide, prevent movement of area under threat. As we have seen, one problem is once trained the body tends to maintain these patterns after the stimulus has gone.
  3. The Pain system itself - this lets you know what is going on i.e. you feel pain
  4. The Endocrine system - Mobilises energy stores and suppresses any processes that are not vital to save energy (growth, repair processes, inhibition of inflammation, and inhibition of the immune system)
  5. The Immune system - responds later and fights invaders, sensitises neurones, makes us sleepy to promote healing.
  6. The Parasympathetic system - also responds later, it nourishes cells and heals tissue.

These systems are designed to work really hard for short periods in a threatening situation. They are the same systems that are activated when your body is under acute stress and are responsible to flight / fight responses. In the same way that prolonged stress which maintains long term activity in these systems is is undesirable, pain for a prolonged time causes sustained activity in these systems which causes over-sensitisation.

Persistent, chronic pain:

All pain is real but some pain persists after healing has occurred. This is termed persistent pain or chronic pain. In these situations the brain concludes that a threat remains and you still need protection. The brain can experience similar sensitisation to that described for the spinal chord in blog #2. The pain ignition nodes in the brain increase their sensitivity so less stimulus from the spinal cord activates them. They can even start firing with no stimulus from the spinal cord. The brain also creates more sensors in the pain ignition nodes and produces more chemicals to activate the sensors. This can be particularly powerful when it occurs in the part of the brain that deals with memory - you can relive the pain even though there is no danger to respond to. For example people with whiplash can feel pain when the car ahead stops even though they are not themselves stopping suddenly. The brain areas devoted to different body parts or functions start to overlap making you sensitised to pain in different areas of the body to where the stimulus originally occurred. This is conceptually similar to the chemical flooding of the dorsal horns in the spinal cord. The longer the pain persists the more advance these changes become. When the brain is sensitised it's not just pain that is persistently produced. Other protective systems also increase their sensitivity:

  • The Sympathetic Nervous System makes you more aware and vigilant - as if you have turned a CCTV onto your body.
  • The Endocrine system directs more energy to muscles for flight or fight.
  • The Motor system keeps muscles constantly activated ready for fight or flight.

These systems then send signals to the brain in a self-perpetuating feedback loop. With a sensitive system inputs unrelated to tissue damage are judged as dangerous and can cause pain. You won’t know there is no damage or that its just your brain decided dangerous. It just hurts. Your thoughts are real. Real chemicals are released and real nerve impulses occur. Thought processes alone are powerful enough to maintain a pain state.

Altered muscle activity:

When you are in pain your brain alters your muscles activity. With pain being a warning sign for danger your body firstly increases activation of muscles to ready you to take action - flight or fight. This reaction is to aid protection of the whole body from further threat.

It also changes how your muscles work to help protect the local tissue where the pain is top prevent further damage. These changes cause bracing / splinting of the area by increasing the tension of muscles around the pain, and altering the movement of the whole area to reduce the load on the painful area (such as limping, or grasping the area). This works through taking load off the injured tissue by putting more load through surrounding tissue.

In the short-term these are all a positive strategy by your brain to protect your body. In the long term it becomes a hindrance not a help. 

Long term over-activation of these muscles makes them feel stiff and tight. This tightness can then change how you use other muscles. Smaller muscles who's role is to control and stabilise stop working as effectively as they perceive the larger muscles to be doing their job.

This altered muscle activity will then change how you move, feel and hold yourself.

So in rehabilitating any injury you need to address these changes in muscle activity. This is done with traditionally stretches and strengthening activities as well identifying and addressing threats and fears that are making your muscle system work so hard to protect you.


Gifford L, (1998) Topical Issues in Pain 1. Physiotherapy pain Association

Butler D.S, Moseley L.G (2013) Explain Pain, Noigroup Publications. 

Mense S, Gerwin R D, (2010) Muscle Pain - Understanding the mechanisms, Springer

Melzack R, Wal P.D (2008) The Challenge of Pain, Penguin Books.

Thursday, 1 June 2017

Glutes - the new core?

I qualified as a physiotherapist in 1998 which seems a long time ago now. It was right on the cusp of a new era of physiotherapy treatment. During my training I spent a lot of time electrocuting people with various strange looking machines with the goal of curing all injuries and getting rid of all pain.

Whilst I was becoming a qualified practitioner learning my trade in the health service and studying for a Master’s degree these machines were being pushed aside in favour of the next trend - suddenly all ailments could be cured not by electricity but simply by ‘activating your core’.

A new muscle was introduced to our lexicon. The ‘transversus abdominus’ the magic cure all for back, knee and shoulder pain. Just get the patients to lie on their back and work this muscle in a very specific and magical way and all would become well with the world.

I set about my job of activating patient’s cores with great gusto, armed with my new argot - “zip and hollow”, “tuck in”, “gently pull your core into your spine”. It had to be just right or it wouldn’t work.

Once your patient's core was activated they were then shown how to challenge it using a very specific and precise series of exercises. We even had a gadget to measure whether the patient was perfectly working the core.

The result of all this precise deep abdominal activation was, well, not a lot.

I then started reading the research it was all based on - a few studies by some Australians - and realised that there were significant flaws in their arguments. Further reading found that there were many ways to work the muscles around the back and many of them far more enjoyable and effective than the strange ritualistic exercises we had been prescribing.

For me the final nail in the coffin came with a study published a few years ago showing that whilst exercise does help to reduce lower back pain no particular type of exercise is any better than any other (study).

What next? A period of sober self-reflection, perhaps challenging ourselves and our assumptions as medical practitioners?

Or instead, how about a new wonder muscle? The Glute.

Suddenly all my patients had weak, underactive, lazy glutes that just weren’t firing.

The cause for all these deactivated bums? Too much sitting. So you poor runners with your ITB, shin splints and achilles pain had all better get your glutes firing. Squeeze squeeze squeeze. You’d better clam and bridge for all you’re worth.

So everyone got better, right? Guess what?  Results were sketchy. Some patients recovered, others did hundreds of clams and bridges daily with no change to their symptoms.

So I shouldn’t bother with glutes exercises, or core, or Physiotherapists for that matter?

Well, not quite. All these muscles are important and may need looking after but they aren’t a cure for all pain and ailments.

The largest bum muscle, gluteus maximus, is a powerful muscle that helps power you forward when you run. The faster you run the harder the glute has to work. This is why sprinters tend towards a rather large behind.

The deeper gluteus muscles (medius and minimus) support and stabilise the pelvis as you run so when you land on one leg they provide the scaffolding to keep the leg steady to enable you to push off.  

So they are really important?

Yes…... but as part of a whole system. They work with other muscles, fascia, tendons, bones, joints, and nerves.  These other tissues and muscles all have their own part to play. Strengthening the glutes in isolation will rarely do very much.

In clinic I often see patients with ongoing issues after being treated by several other physios. They arrive confused and frustrated with their problems. Like many others they have been told that the cause of their problems is a weak core, glutes or both and have then engaged with their prescribed exercises for sometime with little benefit.

Case study 1

Sarah arrived in clinic with ongoing lower back and bum pain that was stopping her enjoying running. She had seen a physio previously who had declared that her glute wasn’t working. She had been given the standard bridges and clams and worked hard at getting her glute to work. But the pain continued and she still struggled to run. Her logic was that despite all the work she had done she still had a ‘weak’ glute. Her glute whilst lying on her side was very strong but in the one leg stand position which is key for running this strength didn’t translate into a strong stable leg.

She underwent a rehabilitation program focusing on balance and control on one leg, working all the muscles including the glutes in a running relevant position. She improved quickly and then slowly built up her pain free running over time.  

Case Study 2

Like Sarah, Mary came to see me after having seen several other physios. She had pain in her hamstring tendon which kept flaring up when she did a bit more running especially downhill running. She had been told she had poor biomechanics on the injured side and needed to strengthen her glutes to correct this.

On assessment the hamstring muscle on that side was much weaker, following a previous tear, thus when running downhill the weak hamstring caused more load on the hamstring tendon. For Mary treatment was based around hamstring strength work and advice on building her running up and discussing technique when descending.

Case Study 3

John came to see me after nearly two years of pain and frustration following an accident which injured his knee. He had been prescribed many exercises including some of the standing  exercises described below,  but he had still not fully recovered.

He had ongoing changes to strength, control and balance through his injured leg but he was also struggling with the changes the accident had had on his overall fitness and lifestyle.

For John the key to progress was developing a greater understanding of injuries, damage and pain pathways alongside guidance as to how to build his fitness and physical cofidence back up to the level he once enjoyed. This included glutes exercises to address the reduced strength and control on the right leg, but this was only a part of the overall treatment plan.

For more information on how pain works see these previous blogs. (here, here, and here)

So how do I address the glutes when assessing and treating in clinic?

  • If I give a strength program to help reduce the risk of injury I will always include exercises to strengthen the glutes. Including some exercises that mimic how they will be used in the person's sport.
  • With any lower limb injury I will always assess how the glutes are working and if I have any concerns I will include glute strength exercises in any rehab program. But rarely is it just the glutes I want to target.
  • I will always tailor the glutes exercise I give to the specific needs, strength and ability of the patient.

So... what should you do?

I would recommend everybody to do some form of strength work as part of their training or even just as part of their life. Its pretty clear from research that all exercise is good for us and strength exercises are one part of this.

For people that do engage in sport evidence shows that strength work reduces injury risk and improves performance. For injuries evidence is also strong to show that exercises are one of the most useful tools we have to resolve the injury and reduce pain.

And when you engage in any strength program I would include some exercises to work the glutes.

So here are some different glutes exercises. I have split them into floor exercises and standing exercises that more closely mimic how we use the glutes when we run. I wouldn’t do all these exercises, just find two or  three exercises that you find challenging but not impossible. A combination of floor and standing exercises are good.

If you find 30 reps of an exercise is easy then you need to make it more challenging. I have suggested ways of doing this at the end of each exercise.

Floor Exercises

1) The Clam with variations. Find the one for you. You need to feel it working your glute and not cause any pain

Standard clam (feet together, lift the knee up an down) 

Standard clam with feet in air.

Reverse clam - (knees together, lift the top foot)

Reverse clam with feet and knees in air

To make harder add a resistance band around the knees for the standard clam and feet for reverse clam.

2) Side plank leg raises - a great exercise to work the ‘core’ and both glutes. These variations get progressively harder.

Side leg raise

Half side plank leg raise (on elbow)

Full side plank leg raise (on elbow)

Full side plank leg raise (on hand)

3) Front plank leg raise - extend hip by lifting foot up to ceiling (mainly works glute max as well as the ‘core’)

Standard leg raise

Elbow plank leg raise

Hand plank leg raise

Standing Exercises

1) Step up to balance

2) Side step up to balance

3) Single leg seated squat

4) Bulgarian split squat - drop hips down and bend knee (like your seating down)

Make these harder:

  1. Higher step (exercises 1 & 2)
  2. Lower seat (exercise 3)
  3. Add weights (kettlebell, weight plate, dumbbell, bar, rucksack with bags of sugar in!)
  4. Do the exercise very slowly and controlled (builds balance and control)
  5. Do the pushing up phase of each exercise as fast as possible (builds power)