Manage Your Pain: Practical and Positive Ways of Adapting to Chronic Pain - Michael K. Nicholas, Allan Molloy, Lee Beeston, Lois Tonkin (2012)

Chapter 1. What is Chronic Pain?

Summary:

There are important differences between chronic and acute pain.

• Chronic pain is long-term pain and acute pain is short-term.

• Chronic pain is just as real as acute pain, but it is not due to new harm or re-injury.

• Chronic pain is maintained by changes in the central nervous system.

• At present, these changes cannot be reversed although some medications can dampen the effects for some people.

• The focus with chronic pain is managing it, not relief.

• Managing chronic pain means learning how to keep active despite the pain.

• This can also mean tackling mood and sleep problems directly instead of waiting for pain relief first.

• A co-ordinated and consistent approach to managing chronic pain is recommended. This book should help you and your carers to take a consistent approach. 

It is quite likely that you and your family or friends have never really understood why your pain has gone on and on. After all, most people have pains which settle within hours or days. Without going into too much detail, it may help to briefly explain the difference between your persisting pain and the short-term pains everyone has at some time.

Pain may be divided into two main categories: acute and chronic

Acute pain is short-term pain. It doesn’t last very long – anything from a few seconds to a few hours or sometimes a few days or weeks. It is a type of warning signal that tells us something is wrong with our body, such as an injury. We may know what to do about it ourselves or we may go to our doctor about it. When the doctor has diagnosed what the underlying problem is, s/he will try to treat it. If the diagnosis is correct and the treatment successful the pain will be relieved fairly quickly. Sometimes acute pain will even be relieved without any medical treatment at all. An example of this would be acute back strain – in about 80% of cases this pain will ease off by itself within 2-3 weeks without any medical treatment (just reduced activity to begin with, followed by a gradual return to normal activities will be enough in most cases).

To re-cap, acute pain is short-lived and is normally relieved either by healing processes, some “hands on” physiotherapy or chiropractic treatments (where the therapist physically manipulates your muscles and joints, or applies heat or cold), some form of medical or surgical treatment, or just by taking a few simple pain killers like Paracetamol.

Chronic pain, on the other hand, is when pain persists for longer than expected. It can last for anything from 3 months to 30 or more years, despite treatment. Chronic pain is often called persisting pain and throughout this book the two terms will be used interchangeably. There is no fixed point at which acute pain becomes chronic – it is just pain which persists longer than might be expected. Mostly, we define pain as chronic after it has been present for 3–6 months, but this varies. For example, chronic back pain often starts with short-lived episodes which settle, only to recur within a few weeks or months. Over time, these episodes may become more frequent until the pain seems to be there almost every day. However, the intensity of chronic pain usually varies and people with chronic pain often describe having good days and bad days, depending on the level of pain.

If you think you are alone in having chronic pain, we can assure you that you are not. Studies around the world have shown that between 10-20% of the population have some form of chronic pain at any one time. In countries like Australia, the US and Europe the figures are close to 20%.

Causes of pain

There are two main types of pain that may become chronic

1. Nociceptive pain

This is pain due to tissue damage like a broken bone, a sprain, or a disease like arthritis. In the case of an injury, this pain normally settles as the tissue heals, but it can persist after healing and become chronic. Sometimes the pain may settle for a period then recur and over time become almost constantly present with fluctuating severity. When you get to this stage the pain is no longer acute and nor is it being caused by the original injury. Changes will have happened in your central nervous system (your brain and spinal cord). These are explained in the next sections.

2. Neuropathic pain

Neuropathic pain is increasingly recognised as a major type of pain and is due to damage to the nerves. This can be in an arm, the spinal cord or the brain. It can often confuse doctors and other health professionals as the pain may be present in an area that has no feeling (it may be numb, but you still feel pain). The pain can also cover an unusual area, such as when it is present in the distribution of more than one nerve. Strange sensations may be reported such as electric shocks, a sensation of water flowing over the part or the area being bigger or crushed. It may also be stabbing or shooting, burning or freezing, even when the rest of you feels normal.

Neuropathic pain is best understood as being due to changes occurring in the nerves of the central nervous system (that is, the spinal cord and brain) after an injury to a nerve. The injury can be to a nerve in your arm or leg, but the effects on the central nervous system can remain long after the original injury has healed. It is still real pain even though there may be no new damage seen on scans like MRI. Some cases can be thought of as like sunburn where the skin is painful and sensitive to clothes and a hot shower. Fortunately, with sunburn the skin heals and the sensitivity goes away. But with sensitivity due to nerve damage, it may not go away, especially if changes happen in the central nervous system. Another example would be to imagine when an amplifier on a music system is turned up, in this case the same electrical signal will produce more noise. Similarly, a car alarm that is more sensitive can be set off by the wind rocking the car slightly. Your doctor may talk about this pain as being due to an increased sensitivity in your pain nerves.

Three common examples of chronic neuropathic pain are:

(1) Shingles

Shingles occurs after an infection with the chickenpox virus. Despite healing of the acute skin rash, the pain may continue in the same area for many years particularly in the elderly. They report often symptoms of the skin being sensitive and painful if touched for example with clothing or bed covers. The pain may be described as burning, stabbing and shooting. The pain can become suddenly severe with no warning and without any further injury. This is called a paroxysm. Surgical attempts have been made to cut out the pain by removing skin and deep tissue but the pain usually remains in the same site. There are a number of treatments for this and some may be successful in reducing the pain. These treatments seem to work best when they are started as soon as possible after the onset of the pain. If the pain cannot be adequately relieved then the approaches in this book should be tried to manage the pain.

(2) Phantom Limb Pain

In some situations it may be medically necessary for a foot or arm to be amputated for example to control infection or after major injury. Patients may wake up with the pain in their leg or arm and think that the operation had not been done. This is more likely if pain was present before surgery. Phantom limb pain may also be felt in the legs after spinal cord injury. Motorcyclists and water-skiers who suffer spinal cord injuries after an accident often describe this pain as crushing with electric shock sensations, as well as hot or cold sensations despite the limb usually being numb. Effective methods of reducing (but not curing) phantom limb pain are now available and these can help some (but not all) of the people with this pain. In addition, many of the coping strategies described in this book can be very helpful in managing these types of pain, but they do need a lot of practice to be effective.

(3) Complex Regional Pain Syndrome (CRPS)

This is often a very puzzling pain as it can arise in an arm or leg after an injury (like a sprained ankle or crushed hand) or no specific injury (some patients recall just bumping into something). Often there is nothing found on scans of the painful area, but yet the skin in that area can be obviously different, with swelling and colour changes being common. The person affected often reports the affected area sweats more and alternates being burning and freezing. The pain can be aggravated by even light pressure (the touch of bedsheets or a shoe, for example) and it can spread, starting in one arm and spreading to the other. This type of chronic pain can become very disabling as any movement of the affected part can make the pain worse. As a result, people with CRPS often end up avoiding the use of the affected arm (or leg) and over-using the other limb, which can then become a problem too. Some medications for neuropathic pain can help, especially if taken soon after the diagnosis is clear, but it is also very important that you start moving the affected limb as soon as possible, despite the pain. This takes courage and confidence. The methods described in this book can be very helpful in getting started and keeping going. The good news is that many of the symptoms of CRPS can be well-controlled by these methods.

Many chronic pain conditions involve both nociceptive and neuropathic elements

Many people with chronic pain have had an injury and for some reason the pain associated with that injury (or injuries) has never really gone away – or not for long – even though healing from injuries is more or less complete after about 3 months. The reason for this is not fully understood, but many scientists now believe that chronic pain is due changes in the central nervous system (that is, the spinal cord and brain) even though no actual nerve damage can be found. The main change is in the ways in which the central nervous system responds to stimulation from the rest of the body. This change is called central sensitization and we described it in the neuropathic pain section above. It is now thought that central sensistization can happen not only when a nerve is damaged (or cut, like a spinal cord injury), but also following an injury that is less specific and does not involve obvious nerve injury (like a sprain).

Putting it simply, when the central nervous system becomes sensitized it activates signals like those that follow an injury regardless of whether a new injury has happened or we have just put pressure on the skin. These signals can be interpreted by our brain as pain and we react accordingly. Unfortunately, our brain may not be able to tell the difference between a new injury and pressure on the skin. The pain you feel is still real but the cause is not due to a new injury or noxious stimulus.

However, the presence of sensitization is difficult to diagnose as it does not show up on scans. Unfortunately, even if such a process is thought to be present curative treatment options are presently limited, but we are now much more confident that these problems can be managed and their impact on our lives greatly reduced. This is the key message of this book. These processes are described more fully in Chapter 3.

Patients often want to know what type of pain they have. However, in many cases it is currently impossible to be really sure, especially if elements of both types are present. The point can also be made that if the pain can’t be relieved the realistic treatment options are the same, namely, to learn to live with it.

Taking a new perspective on chronic pain

In many cases there may be no clear explanation as to why the pain is persisting. But unless you have certain diseases (such as rheumatoid arthritis), it will be true to say that chronic pain is not a warning signal of new damage. Even if you do have something like rheumatoid arthritis an increase in pain severity doesn’t always mean there has been new damage. If a disease is causing your persisting pain, your doctor should be able to diagnose it and advise you on a suitable treatment. The most obvious disease of concern would be cancer. Your doctor should be able to clarify this for you. If cancer is diagnosed and appropriate treatments are undertaken good results are often obtained, especially if it is picked up early.

If you have been diagnosed with cancer and you are being treated for that you might still be experiencing continuing pain. In most cases analgesic drugs will help to ease this pain quite effectively, but you might still find the methods outlined in this book could be helpful. You would need to bear in mind that the book is mainly directed at people with non-cancer pain and so some sections may not apply to your pain. But, at the end of the day, pain is still pain, however it is caused.

Whatever the possible causes of chronic non-cancer pain, there is no way of curing these problems at present. In addition, the treatments which work for acute pain are often not helpful for chronic pain, and may even make matters worse in the long run. For example, while brief rest can help many acute pains, prolonged rest may simply make muscles and joints weaker. Long-term use of pain killers is not usually the answer either and often results in unwanted side-effects. Once physiotherapy has been adequately tried, persisting with it is unlikely to help, especially where the physiotherapist is doing things to you, like manipulation or electrical stimulation. Similarly with surgery, once it has been ruled out or tried without success, further surgery for the same chronic pain problem tends to be unsuccessful and, of course, runs more risks of making matters worse.

Once pain has become chronic (that is, lasted for more than a 3-6 months despite treatment), it is quite likely that the underlying physical problem will have become much more complicated than it was to begin with. Accordingly, a simple “cure” is most unlikely. In short, once a chronic pain problem has been thoroughly and competently investigated and treated – without success – it has to be accepted that there may be no cure for it available at present.

Whatever the original cause of your chronic pain, the persisting pain will probably have led to many changes in your daily life. For example, because of the pain you will probably do less and less of the things you did before your pain started. This will result in a loss of general fitness and strength in muscles and joints, making them stiffer. This, in turn will probably lead to more strain and pain whenever you do try to do things. For example, when their pain is more settled, many chronic pain sufferers try to catch up with all the housework or activities they haven’t been able to do for a few days. This will often aggravate their pain because they have over done things. Repeatedly experiencing aggravated pain whenever you try to be active can lead to feelings of discouragement and defeat.

As a result of doing less or having to give up some of the things that were important and/or enjoyable to you (such as your job, hobbies, sport, household chores etc.) you are likely find yourself feeling more depressed, isolated, irritable or more helpless than you can remember feeling in the past.

The sense of depression and helplessness may well be aggravated by the repeated failure of different treatments to help. The ongoing pain can, of course, add to these problems, making it even harder to cope. These feelings can also lead people to become more and more desperate in their search for a cure. This is a time when you are most vulnerable to claims of miracle cures – only to be let down yet again when they don’t work.

When Chronic Pain Becomes a Problem

Most people in pain try various types of medicines or drugs, especially pain killers. Unfortunately, while these can help to ease acute pain and may even help at times with chronic pain, as time goes on they are likely to help less and less as your body gets used to them. Even so, many people in chronic pain will go on taking the pain killers, perhaps feeling that it is all they can do. However, with long-term use many of these tablets will probably result in a number of unwanted effects, such as an upset stomach, tiredness, loss of concentration, and bowel problems. These problems can add to the suffering caused by chronic pain.

Eventually, in addition to having chronic pain, you can end-up with a number of other problems which all have the effect of causing you even more suffering. The diagram on the next page summarises many of these problems which often follow chronic pain. It is likely that you have experienced some or all of these problems at times because of your chronic pain.

It would seem, therefore, that if there is no cure for the underlying cause of chronic pain, dealing with some of the problems caused by the pain could help to at least reduce the total impact of the pain on you and your lifestyle. The approach outlined in this book is especially aimed at helping you to deal with these problems.

Our understanding of persisting pain has become increasingly complex and so has our approach to treating it. While people with persisting pain may once have been treated mainly with medication like analgesics (“pain killers”), it is now realised that these are often not enough. This is especially true when pain starts to affect many aspects of someone’s life – their home life, their work, their mood, their sleep, their recreation – all the things that go to make up the quality of someone’s life. Modern approaches to treating persisting pain usually involve dealing with most or all of these areas as well as the pain. This book describes an approach that involves drawing on the expertise of medical pain specialists, clinical psychologists, physiotherapists and nurses who try to work in a collaborative way with the person in pain and their general medical practitioner.

Of course, if you can take on board the approach outlined in the book yourself, you may not need to see all of these health professionals. Working with your general practitioner on putting the program into practice may be quite enough. However, you should be prepared for quite a long struggle, with many ups and downs along the way. It can take months, or even longer, to get the hang of this approach and then you have to keep doing it.

It is important to remember, that because the pain is chronic the approach described in the book will not cure or relieve the pain. But many people have found that by dealing with the problems caused by the pain, the pain troubles them less than it once did.