Chronic Pain such as Complex Regional Pain Syndrome

The following was a letter written as a response to an enquiry posted on a Neuroscience Forum regarding a Chronic Shoulder Pain. However the principles outlined here can be applied to any body part.

It is about Chronic Pain as a syndrome and in particular it relates to Complex Regional Pain Syndrome(CRPS).

Many Chronic Pain syndromes overlap in their symptoms and treatment. Bearing in mind no two people are the same, and treatment is always individualised.

I am not a Functional Neurologist and I am a member of Australasian Association of Functional Neurology. This area is of particular interest to me as it has been and continues to be a very difficult puzzle to solve. In working with patients for over 35 years I still don’t know what I don’t know!

I do know that the more I learn the more I realise the vastness of knowledge yet to be learnt. I reserve the right to be wrong at all times. Meanwhile the modern understanding of Neurology is changing rapidly.

CPRS which used to be called Reflex Sympathetic Dystrophy is a formidable disease process and I often wonder how I would go if I had it. The old name more accurately describes part of the pathogenesis I think. More succinctly it is a presentation of both Centralised and Peripheral Pain.

The condition requires a herculean effort by the patient to get it under control. In my experience it takes a lot of intensive, well considered treatment. Success involves a dedicated patient and the ability of the practitioner to see the patient’s ‘bottom line’. i.e. what is important to them, what drives them, and to tailor the rehabilitation exercises to fit that. It could be that the phenotype (a person’s individual makeup,ie their Genes combined with their Environment) that suffers Centralised Pain is also one that involves a dysfunction of the Frontal and Limbic lobes causing a lack of motivation. Or maybe it’s just very hard to be motivated when you are in agony! So it’s important to keep the treatment specifically targeted. Make a difference early and use it to motivate.

Generally, as I said, I approach this as two coinciding problems of Central and Peripheral Pain.

Firstly lets consider the sore body part.

Apart from the incredible pain from touching the painful spot you should see evidence of Autonomic Nervous System aberrations, Dermatographia (mottled discolouration of the skin), prolonged Venous Flushing, Allodynia, smooth dry discoloured skin, inability to sweat and no body hair at the site of pain. There will likely be Hypereflexia, Hyperalgesia, weak muscles, cold hands and feet, they may suffer Insomnia, Hypertension, Depression, Fatigue and have decreased socialisation et cetera.

It is thought that an aberrant Somato-Somatic reflex at the spinal cord level is maintaining the Peripheral Pain, probably by overriding the ‘Gate’ ie disinhibition of the dorsal horn interneurons. This is old school chiropractic thinking but some current research suggests it is not far wrong. Anyway, what to do about it? Heidi Haavik, who wrote ‘The Reality Check’ tackles this concept well. Backed by her original neuroscience research, which I understand to increase the sensorimotor integration and re-establish the previously hardwired circuits, or to build new ones — nobody knows yet which it is. In the early days it was thought of as ‘Use it or lose it’. It turns out that that was more or less correct.

Anyway, stimulation of the receptors, will make receptors do their thing and begin to re-habituate the nervous system. Many repetitions are required to do this. Possibly multiple motor repetitions modulate thalamic pathways also — who knows!

Before stimulating these receptors it is necessary to ensure the O2, fuel and H2O is adequate.

In an old patient CoQ10 and Magnesium is a no-brainer. I use Magnesium 400 mg per day in the chelate form but it probably doesn’t matter what type you use as long as the as it is taken daily and CoQ10 @ 200mg per day. There may be many more useful supplements but I usually defer to others to assist with this.

The patient must be diet conscious or open to learning to achieve an excellent diet. Think Gut-Brain Connection. When the diet is free of additives, preservatives, colourings, fungicides, antibiotics and excipients the cells must be better able to function as they had evolved to do. Sugar is inflammatory and we don’t want that getting in the way of our treatment. Likewise adequate water intake is necessary to set them up for decent metabolism. Of course all this varies from patient to patient. O2 we deal with later.

These patients are always on a bucket full of drugs. Of course, the minimum is best, as you don’t want to be treating the medication. By the time they come to me they are usually well addicted to opiates (it only takes 40 mg daily for 90 days to establish a dependency, ironically its usefulness as an analgesic diminishes rapidly at that same time), and antidepressants.

This is tricky as I can’t interfere with medication as I am a non-prescribing physician. It is something that the patient must work out with their medical doctor by getting directions on how to alter their dosage according to the goal of reducing their medication. Regarding the Opiates, patches are a good change from tablets.

On the topic of other practitioners, I have always encouraged their use provided they do not interfere with my program. Many therapies can be a useful source of stimulation if nothing else. There are plenty out there that

can enhance the process. Psychologists, pain clinics, acupuncturist’s and massage have all been useful. Especially the psychologist/counsellor as this area tackles the problem from a different direction and can help keep the patient on the program. Cognitive Behavioural Therapy is known to make a difference. Probably by affecting the Limbic system. The graduated exposure to a noxious/frightening stimulus is, I think, little different to graduated increases in sensory-motor input. Possibly by altering the stimulus threshold or by setting new circuits.

Back to Sensory-Motor integration.

Specific Spinal Adjustments to free the spine of fixations is a regular requirement. It is now well known that Adjustments stimulate the frontal lobe of the brain. This is essential and actually gives us the edge over other practitioners that don’t understand the importance of a subluxation free spine with enhanced S-M integration. Use light trigger point pressure/therapy if it is not too painful. Likewise try stripping the neurovascular bundle gently with a slippery thumb to stimulate the Sensory Afferent and Visceral Efferent nerves, IF it is well tolerated. In the beginning it won’t be! When you do this and the patient is still very sore afterward, you overdid it and probably ruined the therapeutic effect of the rest of your consultation. It is probable that Central Sensitisation is maintained by ongoing Peripheral nociceptive afferent input such as mechanical stimulation! Start gently. I like to use a Heart Rate Monitor (Pulse Oximeter) to monitor this type of therapy. If the rate goes up — we back off. Remember these patients have had so much pain they consider suicide daily! Hence the antidepressants — they are useful, until your treatment starts to work and the patient can see that, at last, there is someone who is helping them move toward normality rather than just managing their disability.

After care exercises are the most important part of your treatment! This is when the patient treats themselves as you have directed. They do the work but you get the credit, it’s a strange world. The best patient I have had was a nurse who did four hours of exercises daily for the first three months and managed to halve her medication! It was a great start to her treatment. She is now pain free after 10 years of pure 24/7 agony. Remember we are thinking of increasing the sensory-motor integration of the affected part.

MUSCLE AND JOINT MOVEMENT.

Try Shoulder rolls-as big a movement as possible, 30 times forward and the same backwards, as fast as possible, done six times daily. Do both shoulders, in the same direction and in the opposite direction. Mix it up. Use Isometric, isotonic and Range Of Motion shoulder exercises. Work towards push-ups and pull ups. Start push-ups against the wall and gradually work to using a bench top, then desk, then floor. You get the idea. It’s all about movement. Stimulate the muscle spindles, golgi tendon organs, ruffini…… but not the Free Nerve Endings,ie pain receptors. So don’t let them ‘go through the pain ‘ this will just neuroplastically reinforce the already well habituated noxious pain pathways and attenuate the desired transmission of the other desired receptors. The research says a new noxious pain is not connected to the already established centralized pain but Pain Is A Bad Thing. New injuries slow up the therapeutic process and prolong the treatment period.

TEMPERATURE

Get hot and cold packs and apply them for a couple of minutes, swap them around, apply them alternately, mix it up, the brain likes novelty. Perform twice daily.

VIBRATION

Use a tuning fork on bony prominences and the skin. Have them use anything that vibrates and apply it to the shoulder area. Have the patient concentrate on each activity and feel the quality of the stimulation. I don’t mean to be “airy fairy” here. Concentration on the activity is necessary at the cortical level which we will discus soon. Even when doing exercises, thinking about the exercises reinforces the value of them. Its a Mindfulness thing.

CORTICAL considerations.

Now we approach the ‘dark side’. I shall refer you to 3 articles which I found useful.

1 Spinal Presynaptic Inhibition in Pain Control. Neuroscience 2014

2 Kinaesthetic Neurons in the Thalamus of Humans with and without Tremor. Exp. Brain Res. 2003 150 85–94

3 Complex Regional Pain Syndrome : Mystery Explained, Lancet Neurology Nov 2003.

On the topic of information, the literature agrees that a well-informed patient is more likely to continue treatment and gain success. I suggest you give this discourse to your patient.

Why do multiple people damage their limbs and only 1% develop CPRS?.

I suppose a particular mix of chemical, psychological and neurological factors favour chronic pain, which is probably a disinhibition of the thalamo-cortical pathways leading to habituation and further disinhibition at the

spinal cord level. This neurological imbalance and compromised lifestyle very quickly affects the PreFrontal Cortex which upsets the ANS and a further bunch of signs and symptoms develop. Probably, from an epigenetic perspective, the sympathetic system was probably very over active for a long time. Think Sympathetic Dominance and all that it entails, ie the chronic windup of the Mesencephalic Reticular Formation. Perhaps the habituated Centralised Pain is a similar ‘wind up’ involving the Anterior Cingulate Circuits?

Lateral Pain System. The Somatotopic representation of the shoulder on the primary somatosensory cortex (S1) is small and bounded by the elbow and trunk.

Some research suggests that the misery that has befallen the injured shoulder has contracted it’s Somatotopical representation due to decreased movement but recruited and expanded the number of neurones used for the awareness of Pain at the Anterior Cingulate Cortex. That is, the Brain has neuroplastically changed. It has learnt or rather, habituated the pain sensation, just like learning to play a guitar, juggling or riding a bike.

How do we ‘unlearn’ the ability to ride a bike? By NOT getting back on one and by using the body in similar but different ways!!

To change this painful shoulder neurophysiology, stimulation of both the ipsilateral elbow and the associated truncal areas must be achieved to regain the S1 property. Try strapping a pen to the elbow and have the patient draw on paper in detail for 20 minutes twice per day. They are to aim at becoming expert at this. The idea being that increasingly fine motor control of the elbow will steal back adjoining neurones of S1. This requires 100’s of repetitions to achieve. Check the development of these drawings to ensure compliance. Likewise, for the trunk, strap a laser light to the a.c. joint and stick a maze to the wall. ‘Balance Concepts’ have these for sale. Start close in until it is achievable and then move away and repeat until fine control is achieved. This must be taught and repeated at home.

Medial Pain System. Excitation of the Anterior Cingulate Cortex area 24 (awareness of Pain and unpleasantness) can swamp/inhibit? Area 32 (emotional expression of pain and happiness) leading to a push-pull nociceptive control. So happy thoughts can trump pain as can thoughts relating to motor activity. Of course the vestibular System also connects to the ACC so spinning can decrease pain, likewise sound stimulation of the utricle (100Hz) and saccule (500Hz) or caloric stimulation.

Beautifully elucidated by George Kukurin using the Tone Pacer App.

Possibly the sound stimulation also affects the Inferior Colliculus to alter feed forward activation to the Thalamus? Possibly decreasing disinhibition. What a mind bender!

So I think,

Ipsilateral stroking of a painful area and simultaneously stroking another non painful area can trick the brain into reducing the pain level by ‘disowning’ the painful spot. I use my fingers or a soft nylon brush for 2mins repeated 3 times. For example stroking a sore knee and the ipsilateral elbow.

What’s happening here is very interesting.

Consider one area of pure sensory stimulation (of the elbow), ie a shifting light touch sensation and the other area (the sore knee) which is also experiencing a shifting light touch, but combined with pain, must also normally be simultaneously interpreted at the higher cortical levels. This is especially enhanced if there is visual recognition ie watching what is happening (increased emotional salience from the amygdala). Also the effect is possibly amplified by a cognitive awareness of the ‘strangeness’ of the therapy which involves the Anterior Cingulate Cortex.

With chronic pain, cognition and other higher order functions are compromised to a measurable degree, possibly because there is over expression of pain pathways at the partial expense of other circuits. If ‘Fires together Wires together‘ and ‘Use it or Loose it’ applies then anyone in severe unrelenting pain is going to diminish their usual focus being cognition and awareness of the moment (being distracted) to the misery of increased nociception.

With ipsilateral repetitive stroking by another person, as a source of multiple stimulation, already scant cognitive resources are further forced to operate. Done repetitively this associated new novel plasticity eventually dominates and the pain circuits start to lose their synaptic reinforcement while the newer increasingly prominent stimulus gains greater cortical representation.

It appears, under these conditions, the brains default is to prioritise the pure signal ie the light touch stimulation of the non painful area. Probably because it is less effort to focus on the uncomplicated sensory input. Just like swamping the sensorium by vigorously rubbing a sore spot after hurting it. Or using a TENS machine on a sore joint reducing the pain sensation by replacing it with electrical sensation.

This might be similar to Mirror Box Therapy in that the observed normal joint movement or stroking the skin is ‘attended to’ at the expense of the cortical representation of the abnormal or painful joint. This is considered to be reduced ‘ownership’ of the affected part.

Vibration, heat and ice can also be used contralaterally in this way but ‘hands on’ is better.

I suppose Parietal Areas 3,1 & 2 feed forward to area 5 which feeds to Areas 24/32 which projects to the Thalamus with inhibition of disinhibition of the nociceptive input and/or the limbic ‘do-loop’ pertaining to the neuroplastically facilitated nociceptive pain circuits. This is just my guess.

Contralateral stroking is less effective as the brain is better able to allocate attention to each area when using both hemispheres. The ability to maintain well developed pain circuits is easier. With the same reasoning stroking an area larger than the painful spot will also diminish the effect.

VISUALISATION

Is a powerful technique. Considering our reality is quite plastic it is not surprising. Twice daily have the patient visualise themselves doing a gymnastic routine, a ballet or a complicated and dynamic sport. Complete with a sense of pain-free satisfaction, grace, enjoyment and achievement. This will require practice but perseverance is to win.

I wonder if visualisation indirectly calms down/resets/inhibits the Superior Colliculus to decrease sympathetic activity?

Autonomic Nervous System

I’m sure you have done a complete neuro assessment and discovered a heap of “soft” Autonomic Nervous System signs. Each one can be used to access the nervous system and should be utilised. For example, there is bound to be significant discrepancy with bilateral Blood Pressure measurement done supine, sitting and standing.. Stimulation of the Vagus is to decrease sympathetic activation. I have used a ‘Tens’ type machine over the carotid body for this reason. Have a read about this type of thing in the following article: ‘Access to Vagal Projections via Cutaneous Electrical Stimulation of the Neck: fMRI Evidence in Healthy Humans: Brain Stimulation 2016’.

I routinely use stimulation of the Occulo-cardiac and Carotid Reflexes but using a finger pulse oximeter for checking the response with heart rate. Gargling and Breathing Exercises.

I have not yet done it but I see potential value in applying warm +7°C Pneumatic-Insulflation. I recommend to take cold showers, gulp, yes it is a very good way to stimulate the nervous system. Check out the Dutch ‘Ice Man’ on YouTube and try it yourself. What Wim Hof can do with his Autonomic Nervous System is fantastic.

It is thought the Mammalian Dive Reflex is initiated by Breath Holds and by facial contact with cold water. If you cover your face, especially the forehead and the area around the nose with a cold wet towel, the diving reflex will be activated and slow the heart rate relatively quickly. The Trigeminal nerve signals the brainstem which innervates the vagus nerve causing bradycardia and peripheral vasoconstriction. The colder the water, the faster the reaction. Temperatures above 21°C (70°F) do not elicit a response.

OXYGEN

Deep breathing in various breathing rhythms are all good value. I usually get the patient to do one minute of five seconds inspiration with five seconds expiration a few times daily. I show them the difference it makes using a Heart Rate Variability Monitor (Polar H7) and the Elite HRV App. Showing the difference of the before and after breathing metrics, after just one minute, is dramatic. It often shows a 20% change which proves just how dynamic and powerful breathing is on the Autonomic Nervous System. The Breath Pause (breathe out and hold, build to >1min) is no doubt stimulatory to the Prefrontal Cortex. Resisting the urge to breathe is very difficult for those with reduced PFCx functionality.

VESTIBULAR SYSTEM

The vestibular side of this treatment is also very important and it is a highly individual thing. As a general consideration it seems the vestibular system underpins many aspects of our nervous system. It must not be neglected and it’s another area where the more I learn the more I need to learn.

Initially the patients are drugged to the eyeballs which makes testing very difficult. When they first start all I do is a bit of provocative testing to see what happens. One leg stands, Fukada, Rhomburgs , Finger to Nose, Halmagi and Tandem Rhomberg give a fairly good idea of where they are at. Even just having them turn around three times quickly and record how long they take to recover is interesting. If it takes longer than six seconds to recover (vection to completely stop) then I would give them exercises to habituate for these tests. Eye rolling exercises are a general way to stimulate the the Vestibular system but ‘tolerance’ must be considered. Vestibulo-occular reflex and Gaze Stability testing is essential.

Lately I use a Force Plate Analysis System to compare and assess proprioception, visual and vestibular weakness, gaze stability testing (DVAT) and Videonystography.

As I hope you can see there is a lot of variability in the way to treat people with CPRS and understanding the basics is extremely important. While being creative is equally important.

I really have only scraped the surface of this topic.

Anyway what I have described above has worked for me in the past and I hope it is of some usefulness to you.

David