THE PAIN IN SPRAIN ...

BRUCE I. KODISH [*]

WHY DOES IT HURT? That's probably a question many people ask themselves when they suffer from back, neck or other pain. In some ways it's not a very useful question to consider for very long since the 'why' often implies a kind of awfulizing and catastrophizing attitude that can get in the way of finding solutions and getting on with your life.

On another broader level, however, that question may bring us to consider why anyone has pain. What possible biological purpose could there be for experiencing pain?

The answer to why we feel pain seems obvious at first. The ability to experience pain warns us and protects us from damage. It leads us to reduce or eliminate our discomfort. But although pain can be useful in this way, the pain warning system works far from perfectly.

Some people with serious illnesses like cancer may not feel any pain as their problems develop. Although not inevitable, pain often occurs in such cases at the end stage of the illness when it would no longer seem to serve as a useful warning. [1]

Other people, like soldiers in combat, accident survivors and disaster victims, may not feel immediate pain despite serious injuries. In the heat of the moment of dealing with the battle or the accident, attention may not focus on personal damage as much as on escaping with one's life or helping fellow soldiers or accident victims. [2]

Experiments with hypnosis and placebos like sugar pills also indicate that the amount of pain does not necessarily correspond with the extent of injury. The use of these approaches indicates that physiological states and tissue reactions may sometimes relate, in part, to suggestion, expectation and psychological state. [3)]

In other cases, some people are believed to have psychogenic pain. Such pain may be considered by some to have a psychological origin without tissue injury. The person is believed to be expressing internal conflicts and personal problems in the language of bodily distress. [4]

People may also experience pain long after an injury has healed, when damage is no longer impending or occurring. The phantom limb pains often experienced by people who have lost a limb are a good example of this type of process. Some chronic back and neck problems may also involve this kind of condition. This may have something to do with damage to nerves which can then become hyperexcitable, or to other nervous system mechanisms.

The phantom limb phenomenon also brings out the point that we often inaccurately locate the source of pain. You need not have had an amputation to experience referred pain, where pain is projected to - experienced in -- an area of the body other than the site of injury. [5]

As we grow up we learn to associate the site of an injury with a specific area of the skin that we can see or touch. We do this because we do not have visual and tactile experience with areas deep within our bodies or even deep in our muscles and joints. We may thus project or interpret input from such areas as coming from another part of the body (the skin) that shares a common nerve pathway, but with which we are more familiar. [6]

For example, pains felt in the muscles of the buttocks or down the thigh may have their actual source deep in the joints of the lower back. This can be confusing but, fortunately, referred pain patterns have been mapped out. This can help health professionals pinpoint the pain source.

In various ways, then, the pain warning system appears less than perfect. Nonetheless, there does remain some cause-effect relation between pain and injury. Pain can warn us that damage is impending or occurring. The changes that we observe in relation to the pain we feel can give us some indicators about what to do and what not to do. We can learn how to heed the messages of pain more carefully.

What 'Is' Pain?

Pain is not something in a bone, muscle, joint, etc. "The pain in sprain is mainly in the brain!" [7] In other words, your nervous system constructs the complex psycho-physical experience of pain. The International Association for the Study of Pain defines it as "an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage." [8]

A useful framework for understanding some of the more specific mechanisms of pain perception is the Gate Theory of Melzack and Wall, first formulated in the 1960s. [9]

According to the Gate Theory, messages from receptors sensitive to noxious input travel along certain nerve fibers into various transmitting cells in the spinal cord. These transmitting cells then send their own signals to higher levels of the nervous system/brain and to other cells that signal muscles to contract.

Transmitting cells are influenced not only by 'pain' input but also by the input of other sensory receptors from skin, muscles and joints. These other receptors are called mechanical receptors and convey signals related to touch, movement and other non-noxious stimulation.

Transmitting cells also get input from cells located in another part of the spinal cord that serve as the 'gates' of the theory. These gates can shut down or open up the transmission of potential pain messages.

Both the 'pain' and touch/movement messages branch into these gates, as well as to the transmitting cells. 'Pain' messages inhibit ('close') the gates and touch/movement messages facilitate ('open') the gates.

If a gate gets opened sufficiently by touch/movement signals, it will inhibit a transmitting cell from sending potential pain messages to higher levels, in spite of input indicating damage. In this way, a sufficient amount of peripheral touch and movement stimulation can reduce or prevent the experience of pain. This explains in part the effects of massage and movement (manipulation or exercise) as well as heat and cold in reducing pain.

The entire system of gating and transmission cells also receives inhibitory and facilitating input from the cerebral cortex and inhibitory input from the brainstem. The existence of these higher-level inputs provides a way to begin to explain how beliefs, attitudes, anxiety, hypnosis, etc., can influence the experience of pain.

The Chemistry of Pain

The nervous system reactions discussed above are mediated by a complex chemistry. This bio-chemical aspect relates not only to how we deal with pain but also to how we think, feel and act in general.

Chemical messengers called neuropeptides are necessary for the transmission of signals from one nerve cell to another. These neuropeptides are related to hormones. They affect and are affected by other organ systems of the body, including the immune system. The neuropeptides and the hormones can be considered the communication molecules of the organism.

Around 1970, scientists gradually became aware of the possible existence of receptors on nerves and other organs for these kinds of chemicals. Receptors for morphine, a powerful plant-derived pain killer, were discovered in various sites in the brain and in other organs.

Scientists reasoned that, if such receptors existed, they did not evolve in order to fit the morphine molecule. There must be some naturally occurring substance in our brains similar in structure to morphine. Eventually, several such substances, which work not only for the pain control but also for the cardiovascular and other systems, were discovered and given the name endorphins for endogenous (inner) morphine.

Endorphin receptors exist in the 'gate' areas of the spinal cord. In the brain, endorphin receptors are wide-spread, although they are particularly concentrated in the limbic system (especially involved with emotions) and in an area in the midbrain. This last area sends powerful inhibitory signals to the spinal cord. It has many connections with other areas of the brain and may account for some of the effects of placebos and hypnosis since electrical stimulation of this area results in wide-spread pain reduction. [10]

This undoubtedly is part of a larger complex system that affects pain perception. It can be affected, in turn, by disease and injury, drugs, sensory-motor stimulation, anxiety, expectations, learning and personality, among other factors.

The neurological circuits and neurochemical connections discusssed here are related to what you do and how you think and feel. They likely evolved because they enhanced our ancestors' ability to survive -- to mobilize themselves to fight or flee from danger and further damage. Each one of us has inherited what Melzack and Wall call these "natural resources in the brain." [11]

The Experience of Pain

You don't need to understand these neurological and neurochemical connections in great detail. It is sufficient to know that they exist and that your experience of pain is intimately related to them. Let us look more closely at your nervous system experience of pain (what you do and feel) shown in the following illustration. (12)

Let's start at Level I. Something happens in your lower back. Let's say that you bend forwards unexpectedly and a bone, disc, joint, ligament, muscle or nerve suddenly gets stretched, compressed, or even injured to some degree (there may or may not be injury).

At Level II, the immediate sensory impact, nerve fibers in your back can be stimulated in response to the sudden mechanical pressure or pull. If injury has occurred, chemicals resulting from inflammation may stimulate nerve receptors. However, at this point, you do not yet have an experience of pain. The arrow from II to III stands for the nervous system processes in the spinal cord and brain involving the gate cells, transmitting cells, etc.

Level III represents the even more complex nervous system processes of your non-verbal experience (what you later call "pain"). If you feel some discomfort in your back or in some other part of your body right now, just notice it. If not, for the purpose of experiment (you are a personal scientist after all!), pinch your finger. What do you feel? Whatever words you then say about it, such as "ouch!" or "it's painful!" etc., are not the experience itself.

Distinguishing your non-verbal pain experience from the way that you talk about it, and learning to observe your pain and other symptoms better, can help you deal more effectively with your symptoms.

With Level IV, we arrive at the verbal level. At this level you describe your experience in words, i.e., "flickering, sharp, dull," etc. Your words may involve judgments and conclusions about your experience, i.e., "dreadful, unbearable, vicious," etc., or "Hmm, perhaps that's a warning, better change how I'm sitting."

What you describe and talk about at Level IV partly depends upon the stress or injury at Level I and your Levels II and III processing of it. How you talk about the pain also reflects how you evaluate your previous experience. For example, you might say things like "How stupid to injure my back again" or "Another onset, too bad! What's the best way to deal with it now?" Which general attitude may be more constructive in the long run?

According to general semanticists, Level IV is not something 'mental' apart from the physical. Rather, your interpretation or evaluation involving language qualifies as a nervous system event as much as what happens on Levels II and III.

Your Level IV interpretation is also not the linear end point of some pain-causing stimulus. Rather, the entire experience of pain, like most other human experiences, is very much part of an ongoing process of circular causation.

This circular or cyclic process of causation is shown in the looping arrows on top of the diagram that go from the 'higher' to 'lower' levels of reacting. In practical terms, this means that your evaluation of your back pain (the meaning you give to it), which includes how you talk about it to yourself, can shape your ongoing behavior and your experience of pain. This means, among other things, that anticipating pain may make you more sensitive to it.

I do not say here that your back pain is just a matter of what you believe and how you behave. I do say that your experience of pain does not simply depend upon some immediate 'noxious' input. Your experience of pain, as indicated in the illustration, depends upon many levels of nervous system functioning. These levels can involve beliefs, attitudes, moods, attention, etc., as well as various drugs and other chemicals, and different types of sensory stimulation and movement, among other factors.

Many Paths to Feeling Better

In this article, I have touched on the fact that pain is not simply a function of injury. Many factors enter into whether and to what extent you will experience pain. Many influences bear on whether the 'gates' of the spinal cord will open or close to let nerve signals become painful experiences. Therefore, it is likely that many different kinds of treatment, working on different levels in different ways, can help you to feel less pain.

It is useful to know that there are many ways of dealing with your pain. The advantage of using activity-related (posture-movement) approaches to deal with activity-related pain is that you deal directly with a significant source of your back pain problem.

As I discuss in greater detail in Back Pain Solutions, non-damaging movement can often usefully reduce the chemical irritants that accumulate after a musculoskeletal injury to the back (or neck, etc.).

Properly guided movements (exercises) may also help resolve activity-related pain caused by shortened muscles and stiff joints.

Non-damaging movement also provides peripheral stimulation that can help open the spinal cord gates that turn off the further transmission of potential pain signals.

Improved posture-movement habits provide a non-irritating environment for the muscles and joints to heal without further damage.

In addition, doing something to take control of your painful symptoms in itself has positive benefits. Taking action for your own well-being provides a sense of efficacy and self-confidence. For one thing, it gets your attention away from simply dwelling upon your symptoms. As neurologist Barry Wyke has pointed out, you should not overlook the power of "ensuring cerebral disregard" (distraction). (13)

How you evaluate the pains you feel at a particular time can make a difference in your ongoing experience of discomfort or ease. It does seem that the pain in sprain is mainly (but not only) in the brain.

(*.) Bruce I. Kodish, Ph.D., P.T., practices physical therapy and teaches the Alexander Technique of posture-movement education in Pasadena, California. Co-author of Drive Yourself Sane: Using the Uncommon Sense of General Semantics, he serves as a Senior Editor of the General Semantics Bulletin and on the teaching staff of the Institute of General Semantics. Adapted from Dr. Kodish's most recent book, Back Pain Solutions: How to Help Yourself with Posture-Movement Therapy and Education, Extensional Publishing, 2001. The book applies general semantics to the problem of activity-related musculoskeletal pain. It is available from ISGS. Reprinted with permission of Extensional Publishing.

NOTES AND REFERENCES

(1.) Melzack, Ronald and Patrick D. Wall. 1982. The Challenge of Pain. New York: Basic Books, p.122.

(2.) Ibid, p.35.

(3.) Ibid, pp.41-47.

(4.) Ibid, pp.47-49.

(5.) Ibid, pp.124-127.

(6.) Cyriax, James and Patricia Cyriax. 1983. Illustrated Manual of Orthopaedic Medicine. London: Butterworths, pp. 10-1l.

(7.) Robert P. Pula, writer/teacher of General Semantics (lecture notes).

(8.) "IASP Pain Terminology" from Merskey, H. and N. Bogduk. 1994. Classification of Chronic Pain, Second Edition. IASP Task Force on Taxonomy. Seattle: IASP Press, pp.209-214.

(9.) See Melzack and Wall, pp.222-239.

(10.) Pert, Candace B. 1997. The Molecules of Emotion: Why You Feel the Way You Feel. New York: Scribner. Pert provides a firsthand account of the discovery of the endorphins and endorphin receptors. See also Rossi, Ernest Lawrence. 1986. The Psychobiology of Mind-body Healing. New York: W.W. Norton. Rossi discusses the implications of the existence of these communication molecules.

(11.) Melzack and Wall, p.402

(12.) The illustration and discussion are based on Alfred Korzybski's model of human evaluation presented in his article, "The Role of Language in the Perceptual Processes," in Alfred Korzybski Collected Writings 1920-1950, Collected and arranged by M. Kendig. Englewood, NJ: Institute of General Semantics. pp.683-720. This model is presented and discussed in Kodish, Bruce I. and Susan Presby Kodish. 2001. Drive Yourself Sane: Using the Uncommon Sense of General Semantics. Revised Second Edition. Pasadena, CA: Extensional Publishing.

(13.) Cyriax, James. 1978. Textbook of Orthopaedic Medicine: Volume One - Diagnosis of Soft Tissue Lesions. Seventh Edition. London: Bailliere Tindall, p.569.