Tuesday, April 10, 2012

The Viscerosomatic Reflex

http://www.ptonthenet.com/articles/Scientific-Balance-Training---Part-5-1843

Thus far in this article series, I have used the Survival Totem Pole to demonstrate the many different factors involved when training someone to improve their balance. We have looked at how sub-optimal function of the respiratory system, masticatory system, visual system, vestibular system and upper cervical spine can negatively affect a client’s ability to balance and may set them up for injury or further dysfunction if given inappropriate balance exercises.
VISCERAL RELATIONSHIPS AND BALANCE
As I’m sure you are well aware, the average person in the gym or physical therapy clinic today presents with musculoskeletal disorders, sub-optimal nutrition and frequently has functional deficiencies within their organ systems. Some of them are in physical therapy programs for injuries such as sprained ankles, hurt backs and fractures of the arms, legs or hip – all of which can be related to poor balance.
While it is certainly logical to think, “if you have poor balance, you need to do balance exercises,” such thinking only displays superficial logicThe human body is a highly integrated, holistic, cybernetic system – a system of systems. If we were simply just a collection of muscles and joints, or some form of sophisticated robot, balance exercises for poor balance approach might just work. But we are not merely a system of muscles and joints, and balance skills development in the absence of unwanted and unnecessary biomechanical stress can only come in concert with balance in the body at the segmental level, both structurally and neurologically. (I am purposefully emitting other systems such as the immune, circulatory, hormonal and limbic for ease of explanation.)
With this in mind, one of the first things someone should look for when assessing anyone with a balance disorder or poor ability to balance for any reason is the health and function of their viscera. While the topic of functional assessment of the viscera is far too vast for this article, I would like to briefly highlight just how potent a relationship exists between the visceral and musculoskeletal systems, and how easily a visceral disorder at subclinical levels can readily effect posture, retard ones ability to acquire balance skills or to simply maintain balance during simple balance tasks.
THE VISCEROSOMATIC REFLEX
I am sure you are all aware of the typical signs of a heart attack - shortness of breath, tightness in the chest and pain, commonly down the left arm. I am equally as sure that most females can tell you about the relationship between menstruation and low back pain. I am also sure many of you have had a significant bout of constipation along with low back or sciatic pain that miraculously disappeared upon completion of a much-needed bowel movement. Those of you that have had a kidney stone will likely remember the severe low back pain that often accompanies the passing of such stones. Others of you who have had a bladder infection probably experienced relief of your back pain after the infection cleared the body.
All of these are common everyday occurrences of viscerosomatic relationships. Yet today, very few health or exercise professionals pay any credence to the intimate neurological relationship that exists between soft tissues external to the thoracic, abdominal and pelvic cavities and those within them. In fact, on a number of occasions, I have had to provide references for some of my students that were being challenged by physiotherapists and other medical professionals for having suggested that there was a viscerosomatic relationship to pain because they didn’t believe such relationships existed!
So how do visceral pains produce musculoskeletal pains and how does this effect balance? Quite simply. As demonstrated belowpain felt in any tissue, be it arteriovascular, visceral, muscular, ligamentous, dermal or otherwise, has the potential to create the perception at a cortical level that all structures on the same sensory channel(s) of the spinal cord are experiencing pain as well.

Image above: Viscerosomatic and Somatovisceral Reflexes. Due to the organization of the spinal cord, pain sensations from skin, muscles and other tissues external to the viscera are delivered to the grey matter of the spinal cord via spinal nerve roots. Visceral sensation is delivered to the gray matter via sympathetic nerves. Upon entering the spinal cord at Lamina I and V, pain impulses from spinal nerves (skin, muscles, ligaments, etc.) converge with pain impulses from viscera and are sent to the brain via a common interneuron. It is because of the convergence upon a common ascending interneuron that pain perception at the cortical level is often not localized to the specific tissue responsible for generating the pain impulses. It is this mechanism that is responsible for the commonly experienced musculoskeletal pains secondary to visceral pains such as left arm pain during heart attack (Ref. Correlative Neuroanatomy 20th Ed. J. deGroot & J.G. Chusid. Pub. Lange 1988
Due to the organization of the spinal cord, pain sensations from skin, muscles and other tissues external to the viscera are delivered to the gray matter of the spinal cord via spinal nerve roots. Visceral sensation is delivered to the gray matter via sympathetic nerves. Upon entering the spinal cord at Lamina I and V, pain impulses from spinal nerves (skin, muscles, ligaments, etc.) converge with pain impulses from viscera and are sent to the brain via a common interneuron. It is because of the convergence upon a common ascending interneuron that pain perception at the cortical level is often not localized to the specific tissue responsible for generating the pain impulses. It is this mechanism that is responsible for the commonly experienced musculoskeletal pains secondary to visceral pains such as left arm pain during heart attack.
VISCEROSOMATIC REFLEXES AND BALANCE TRAINING
Now that you understand the basic neuroanatomy of the viscerosomatic reflex, I would like to point out just how such reflexes can impair a client’s ability to balance and/or learn a new balance skill. To make the explanation more visual, please refer to the image below. To the left of the spinal column, you see the sensory innervation of the small intestine (T5-T9) and the large intestine (T9-L3). When ever there is pain, be it from inflammation secondary to use of medical drugs, food allergy or intolerance, bacterial or parasite infection, gas build-up, constipation or trauma, the pain will be interpreted by the brain as coming from both the dermatomal segments and myotomal segments which correlate with the origin of the pain impulses; there may be a spread of pain inputs over a greater number of segments due to connecting fibers in the sensory system of the spinal cord. The result of such insults in the small intestine (as demonstrated here) may be seen as both pain in the respective regions of the abdominal wall (viscerosensory reflex) or a pain response in the correlating muscles of the abdominal wall (visceromotor reflex) (see diagram of spinal column).
A visceromotor reflex may produce muscle spasm ranging from very mild to very severe. In acute appendicitis for example, the abdominal wall may become rigid and board-like. The abdominal muscles may also respond with pain inhibition. What is critical to understand regarding balance training is that the abdominal wall serves vital functions as a stabilizer of the entire torso, including the pelvis. Regardless of the source of visceromotor reflex, any such reflex inhibiting key stabilizer muscles (particularly of the core region) will serve to alter recruitment pathways, destabilizing the spine and relevant joint complexes at a segmental and potentially a gross level. Attempting balance training, strength training or any functional activity that requires motor skills development in the presence of visceromotor reflexes strong enough to modulate efficient and balanced recruitment of the segmental and gross stabilizer system can only serve to perpetuate faulty recruitment pathways, increase the likelihood of ligament stress and joint inflammation and further inhibition of local and regional stabilizers and prime movers.
This is far more common than people realize. Consider the fact that 85 percent of Americans are on at least one prescription medical drug, many of which cause inflammation of the stomach, small intestine and cause constipation.Additionally, BioHealth Diagnostics of San Diego, California shows that between 50 and 60 percent of all white skinned people are gluten intolerant. The quantity is thought to be  approximately 40 percent for those of eastern origin. This means that half of our population could be suffering from periods of currently unquantifiable stabilizer deficiency.
While a comprehensive explanation of assessment of the stabilizer system is beyond the scope of this article, it is safe to say that anyone taking medical drugs with the side effect of inflammation and/or constipation, anyone with a visceral dysfunction or anyone with digestion or elimination problems is at greater risk of injury and faulty motor programming – especially when exposed to balance challenges by those unskilled at a comprehensive assessment of the visceral and motor systems. Additionally, those that have distention of the upper or lower abdominal wall should be held suspect for possible viscerosomatic reflexes.
At the CHEK Institute, we suggest elimination of all grains except corn, rice, buckwheat and millet for a trial period of no less than two weeks. During this time, my staff, my students and I have all seen dramatic improvements in a client’s ability to stabilize their joints and learn a variety of new motor skills! Once the grains, allergens, sources of food intolerance and/or inflammation are removed from the body, normalizing sensory-motor inputs and outputs to and from the spinal cord, the abdominal wall and any somatic structures related to the problem, the viscerosomatic reflex usually corrects itself and begins functioning more optimally (below).
BALANCE TRAINING AND EMOTIONS
Emotions may be one of the biggest fundamental differences between humans and animals. Emotions can be incredibly healing or incredibly destructive to the body. For example, take a look at the posture of someone who is clinically depressed. I am also sure you are familiar with the fact that people who harbor too much anger, grief, pain or any other negative emotion are far more susceptible to illness and disease than those who do not have such emotions.
While the topic of emotions and their effect on the body is vast, I would merely like to state that, because the emotions have the power to heal or the power to kill, any client’s emotional status should be considered as part of an initial or follow-up assessment process. Most of us are familiar with phrases that our clients emit, such as “so-and-so makes me sick to my stomach,” or “so-and-so is a real pain in the ass.” Next time you are working with someone and you hear them make a comment with a self-destructive connotation three or more times in one training or rehabilitative session, look carefully at your evaluation and you may be surprised to find that they present problems in the exact areas they refer to as they vent their negative emotions.
Keep in mind our brief discussion on viscerosomatic reflexes as you listen to your clients, and you will begin to see more. You will, in fact, begin to see many interesting correlations between their emotional health, visceral health, hormonal health and musculoskeletal health and performance!
And remember, “He who is out of balance on the inside, is out of balance on the outside!
PELVIC INFLUENCE ON EQUILIBRIUM AND BALANCE
The pelvis is essential to postural stability of those structures above and below it. To appreciate the effect of pelvic disposition on craniocervical structures, imagine the body as a skyscraper with a pelvis for a foundation. Similar to a skyscraper with many segmental levels and a roof at its apex, the body has many segmental levels with the cranium at its apex. The removal of an eight of an inch from the anterior aspect of a skyscraper's foundation may not be as threatening to those on the first floor as it is to a window washer on floor 24, in the human body an anterior pelvic tilt of an eight of an inch may produce a substantial postural response 24 segments up at C0-C1. That region has great influence on our ability to balance and be balanced!
The physiological rest or neutral position of the pelvis is defined as the position in which the symphysis pubis and the anterior superior iliac spine lie in the same vertical plane. As the pelvis tips anteriorly, the body migrates anterior to the line of gravity. If the gravity line is posterior to the axis of rotation of a joint, the superior segment tends to rotate posteriorly in compensation. Because the sacrum is attached to the pelvis by ligaments, and is the foundation of the lumbar spine, any increase or decrease in pelvic inclination will affect the degree of lumbar lordosis. It is well supported throughout the literature that increased pelvic tilt (on a coronal axis) exaggerates spinal curvatures, where as decreased or posterior pelvic tilt straightens the spine. This is demonstrated below.
The forward disposition of the body concomitant with anterior pelvic tilt, is much more common than posterior pelvic tilt among athletes, with or without forward disposition of the body. The posterior pelvic tilt is most often a compensatory maneuver in patients having a disk herniation with posterior or posterolateral protrusion. Posterior pelvic tilt is becoming more commonplace due to the increasing numbers of seated workers.
The position of the pelvis, which rides on a ball and socket relationship with the femur, depends on muscular control from above and below. The relationship with the femur, depends on muscular control from above and below. The primary muscles producing anterior pelvic tilt are the psoas, rectus femoris, tensor facia lata, sartorius, and adductors from below and the erector spinae from above. Those muscles primarily producing posterior pelvic tilt are the hamstrings, gluteus maximus, the anterior fibers of the external oblique, and rectus abdominus. The static position of the pelvis will also be influenced by the resting length-tension relationships in these muscle groups. Once the balance of these muscles, which is crucial to synergistic function of the entire musculoskeletal system, is disturbed, a runaway process may begin. Davis’ Law applies to this process. Davis Law states: "If muscle ends are brought closer together, then the pull of tonus is increased, thereby shortening the muscle, which may even cause hypertrophy. If muscle ends are separated beyond normal, then tonus is lessened or lost, thereby "weakening" the muscle."
The anterior tilt of the pelvis shortens the muscles responsible for this movement, encouraging their hypertrophy, while the antagonists perpetually weaken when considered relative to optimal length/force relationships. Lewit and Janda both refer to this as the Lower Crossed Syndrome, which may induce an upper crossed syndrome. Unlike the skyscraper that will soon fall when its foundation is tampered with, the human body seeks to balance by way of righting mechanisms. The response to an anteriorly rotated, forward displaced pelvis is trunk extension toward the line of gravity. The head, in its attempt to level the eyes with the horizon, must come forward via combined neck flexion and upper cervical extension (below). Careful analysis will show that this patient in the above FHP ascribed to many potential musculoskeletal pain symptoms and a reduced capacity to acquire balance skills without greater risk of injury.


The rectus abdominus inserts at the anterior surface of the xiphoid process and costal cartilages of the fifth, sixth, and seventh ribs whereas the external obliquus originates from the external surfaces of the lower eight ribs. The external obliquus inserts at the anterior half of the outer lip of iliac crest and the aponeurosis of the anterior abdominal wall, which is continuous with the rectus abdominus on its way to its origin at the pubic symphasis. These muscles form a suspensory support for the anterior pelvis while serving to support and protect the abdominal viscera. Their position provides a strong mechanical advantage for controlling pelvic inclination.
Whether induced from above or below, the abdominal musculature will transmit the strain of anterior pelvic disposition to the ribs and sternum. This will serve to load the accessory muscles of respiration, compressing the cranium and cervical spine with every breath. Compensation can only occur for a limited period before decompensation causes the individual to seek professional help. In such clients, any and all balance exercises must be controlled and aimed at improving dynamic posture, or improving the client’s ability to maintain an optimal instantaneous axis of rotation in any and all working joints.
Many patients with increased anterior pelvic tilt appear to have a potbelly. This occurs when the pelvic basin, tipping forward, is pouring its viscera onto the abdominal wall. This is further compounded as the pelvis displaces anteriorly on a transverse plane and coronal axis, such that the ribs are pulled caudal into an expiratory position. The diaphragm, in turn, lowers from its normal position between the eighth and ninth ribs, at the back, to a position as low as the last rib, at the back.
The abdominal viscera, relatively unsupported by nonphysiologic abdominal tone, are then pressed distally by the diaphragm, forcing them to merge with pelvic viscera. Evidence exists of visceral ptosis, altered positioning, and circulatory disturbance with concordant dysfunction. Viscerosomatic reflexes producing surface pain and/or visceromotor responses in muscles within relevant myotomes will reduce the functional capacity of the body during balance training or during any form of exercise that loads the body. The idiopathic headache can often be seen superimposed on the progressive total body postural dysfunction, concordant with aches, pains, lethargy, visceral congestion, and often misdirected use of analgesics; a situation which is compounded by the fact that most of the so called health foods sold in gyms today are really nothing more than candied garbage that stimulate the sympathetic branch of the ANS, encouraging a catabolic state in the body.
Many patients who complain of an inability to balance also complain of head, neck, and jaw pain and/or have a history of back pain. This, based on the above premise and the early observations of Dr. Lovett, is logical. The Munkfors investigation, a study of steel and forestry workers, produced objective data to confirm this interrelationship. Of 221 patients who had stiff neck or brachialgia, 85 percent had previously experienced lumbar spine problems. Of 56 patients who had never experienced stiff neck or brachialgia nearly 40 percent had no history of lumbar spine problems. The difference is statistically significant (P<0.001). It is unfortunate that worker's compensation, a significant number of physicians, and insurance companies inherently treat these conditions as entities.
A (true) short leg is often associated with unilateral anterior rotation of the ipsilateral innominate and is synonymous with pelvic torque. Walther refers to Strachan and Robinson, who, using electromyography, found that removing a 3/8 inch heel lift from the shoe of a standing subject produced an altered firing sequence of the muscles of mastication during chewing. Normal occlusal patterns were evident with the lift inserted, whereas patterns of severe malocclusion resulted from removing the lift.
Fonder demonstrated that malocclusion possesses the potential to distort not only the posture of the stomatognathic (upper) system but of the whole body, including the production of pelvic rotation. According to Lewit, the most frequently seen lesion in pelvic distortion is blockage at the craniocervical junction, often associated with psoas spasm. This is in accordance with De Jarnette, who states that any factor irritating the spinal muscles will attack the occiputal-atlas condyle area with greater force than any other. There is little doubt based on biomechanics alone, that pelvic tilt into any one or more of the three planes of motion will alter gait, increasing the likelihood of spraining ankles, straining ligaments in knees or around the pelvic girdle or falling due to reduced balance capacity as the speed of gait increases or change of direction demands are imposed, as is common in many group exercise classes and in sports training today.
Another important but seldom considered anatomical relationship is that of the central nervous system with the sacrococcgeal complex. The dura attaches to the sacrum and coccyx, and is very sensitive to tension and torsion. Should your client have had a fall in their medical history or any significant trauma to the lumbosacral or sacrococcygeal complex, a field of tension/distortion can become set into the dura and spinal cord. Because the body is exquisitely sensitive to any invasion of the CNS for obvious survival reasons, it will frequently attempt to buffer this tension field through the body, unwinding the tension by moving the pelvis spine and torso as needed under the upper cervical spine. This produces a postural dysfunction and loss of balance characteristics very much like that described above in the section on the upper cervical spine and it’s influence on balance (below).
While assessment of such neuromechanical disorders is complex and beyond the scope of the personal trainer or strength coach, it is well within the field of the physical therapist, osteopath, chiropractor and those skilled in musculoskeletal medicine. The purposes of this comprehensive information is to inform the personal trainers and related exercise professionals as to why so many people have a hard time balancing on Swiss balls, balance boards and performing functional activities that require maintenance of ones center of gravity over their own base of support.The current approach to such clients in the exercise industry (and in much of the rehabilitation industry as well unfortunately) is to simply put people on machines that require no ability to balance at all.
Machine exercises are commonly pawned off as much safer for older people and people with poor balance. I believe this is a copout and only serves to maintain dysfunction in those who truly need a skilled approach to physical therapy, corrective exercise and posture and balance skills development. It is time for the exercise industry to step up to the demands of the clientele instead of pacifying the problem by lowering the value and challenge of the exercises to the lowest common denominator in the name of “not hurting anyone”, when in all reality, not learning to assess clients or use exercise skillfully is equivalent to maintaining the disease process. Left unattended the disease process always progresses!
THE SLAVE JOINTS AND BALANCE TRAINING
We are now at the bottom of the Survival Totem Pole, in the region of the slave joints. The slave joints consist of the hip, knee, ankle, foot, shoulder/arm complex and all the spinal joints between C3/4 and L/5-S1. The pubic symphysis and sacroiliac joints can be considered as intimate with the sacrococcygeal system because the pelvic girdle is a functionally closed chain. The reason these joints are called slave joints is because among those skilled at assessment of all the regions superior on the Survival Totem Pole, the slave joints merely serve as buffers willing to be sacrificed by the body in the name of supporting all structures and systems higher up on the totem pole.
While there are hundreds of books written on the assessment and treatment of the slave joints, the key feature regarding balance training is simply that we must remember any slave joint may become a source of pain. Pain, regardless of the source, produces inhibition in the nervous system and commonly results in weakness in the muscles sharing a direct neurological relationship as well as a reflex working relationship with the spinal segment(s) receiving noxious impulses. Therefore, for all the reasons I have mentioned above, after having provided your client with a skilled assessment of all systems superior on the Survival Totem Pole, be it by referral to a skilled medical professional or performed by yourself if you are adequately skilled and qualified, slave joints should be assessed and treated as individual problems with the potential to disrupt balance and hamper development of balance skills.
The medical system today is highly focused on treating the spot that hurts. It doesn’t take a genius to look at the statistics on musculoskeletal dysfunction and disease to see that this allopathic approach has done little at all to improve exercise technologies, reduce the incidence of orthopedic disorders, and certainly has done little if anything to improve balance in any sense of the word in today’s population!
There is a need for expert treatment of slave joints and there is are many ways that pain and dysfunction in these joints can result in poor balance and reduced ability to acquire balance skills, yet we must respect the hierarchical development of the human body and nervous system if long-term progress is to be achieved, or if we are to help our populations en masse with exercise of any type.
If you don’t possess the skill to assess and treat slave joint disorders then I will tell you what I tell all my students, “When in doubt, refer them out!” The last thing you want to do is throw someone into classes and/or expose them to exercises that challenge the balance mechanisms of the body without restoring optimal stability, posture and the functional capacity to balance and learn new balance skills.
In Part 6, the final installment of this article series, I will summarize the key points that have been covered thus far and give you an algorithm to help determine what type of balance training a client is best suited for based on their individual needs.

2 comments:

  1. Very interesting article. I have saved it for further reading and study so I can inform my readers about it more, especially how this relates to pelvic floor pain. www.mypelvichealth.ca

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  2. Thank you so much for this article! It was so informative on the viscerosomatic reflex, as there are not that many articles on this topic. The pictures and diagrams really helped.

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