l
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HEALTH CARE * LES SOINS
Chronic pain and the search for alternative treatments Brian Goldman, MD
This is the last article in a threepart series on chronic pain (the first two appeared in the June I and June 15 issues). Here, Dr. Brian Goldman looks at some of the nondrug treatments being used to treat chronic pain. W r ould x
Hippocrates
be
satisfied with the way today's physicians treat chronic pain? Probably not. Nothing we do is entirely free of harm, our surgical treatments often fail to work and the drugs we prescribe may produce harmful side effects. Although conventional treatments, from orthopedic surgery to neurosurgery and psychotherapy, do have roles to play in treating chronic pain, none is a panacea. This is causing a growing number of physicians to seek alternative methods of treatment. "Alternative therapy" is, of course, a medical cussword. To some doctors it means potentially useful but untested; to others, quackery. There are numerous alternative therapies for treating chronic pain, everything from chiropractic to transcutaneous electrical nerve stimulation and acupuncture. Brian Goldman, a Toronto emergency physician, is a CMAJ contributing editor. 508
CAN MED ASSOC J 1991; 145 (5)
Acupuncture, which generally involves the insertion of hair-like needles into the body's "trigger points," produces an aching sensation and also causes stimulation of specific nerve fibres. This apparently sends the brain a signal, causing it to release pain-relieving endorphins. "The name of the game for pain is to produce a mild ache, not at the painful site but somewhere in the body," says Dr. Bruce Pomeranz, a neurophysiologist at the University of Toronto who has been studying the use of electroacupuncture to treat chronic pain. "It's not unlike the ache you get when jogging." With electroacupuncture, an electrical current is applied to the acupuncture needles to intensify the effect; Pomeranz has developed a device that produces acupuncture's effect without using needles, and patients can use it in their homes. He says electroacupuncture produces its best results in patients with osteoarthritis, although it has helped ones with aches in the back, head and neck. "There doesn't seem to be any pains that aren't helped," he says. Dr. John Loeser disagrees. "I think it's a relatively innocuous treatment with low health hazards that lacks any kind of scientific validity whatsoever," the director of the Multidisciplinary Pain Cen-
ter at the University of Washington in Seattle says. "It may provide benefit to people with certain types of musculoskeletal disorders, but those who say it is a treatment with specific beneficial effects should produce the evidence. "All of the studies done show acupuncture has a mild analgesic effect which is unlikely to be of major benefit for most people. It also has a tremendous psychologic effect because there is a treating person and a treating technology. Studies looking carefully at these issues have simply failed to demonstrate that this is a very effective method of treating people with chronic pain." Pomeranz says many studies are being ignored by the sceptics. "We know a lot more about how electroacupuncture works than about a lot of standard medical procedures," he contends. "For example, we don't know how gaseous anesthetics work but we use them all the time because empirically they work." As the acupuncture debate continues, an east-west meeting of the minds is taking place at the Gunn Pain Clinic in Vancouver. Here, a Canadian physician has fused oriental acupuncture with western concepts of neurophysiology to produce a pain-management technique that is surprising-
ly effective. LE I er SEPTEMBRE 1991
Intramuscular stimulation (IMS) was developed in Vancouver in the early 1970s by Dr. Chit-Chan Gunn, then a staff physician at the Workers' Compensation Board of British Columbia (WCB), where he had become interested in the plight of workers disabled by severe back pain. Gunn and his colleagues studied patients with low back pain who did not return to work and compared them with patients who did. They found a subtle, reproducible difference. Patients unable to resume work had numerous skeletal muscles whose fibres were shortened and tender when palpated; those who returned to work tended to have normal skeletal muscles. This observation was the first piece in a puzzle that led to Gunn's discovery of IMS. In 1973, the WCB asked him to write a report on acupuncture. He observed the technique in China, but was unimpressed. "The Chinese doctors did not have a physiological basis to explain acupuncture - they were more or less using it as a recipe from a cookbook." The board then sent Gunn to New York City to train in electromyography (EMG). On his return, he inserted EMG needles into the muscles overlying traditional acupuncture points to study the electrical activity; at times he used an electrical current to stimulate the region. "As we were sticking needles into certain points, such as the motor point or muscle-tendon junction, we found that the muscles began to relax," recalls Gunn. "I was really astonished when I treated a patient at the WCB who had low back pain for months. When I did an EMG examination followed by stimulation through the needle, the man came to me the next day and said that his pain was completely gone and he was returning to work. Incidents like that convinced me this was a technique worth studying." SEPTEMBER 1, 1991
"The name of the game for pain is to produce a mild ache, not at the painful site, but somewhere in the body. " -
Dr. Bruce Pomeranz
Gunn believes many patients with chronic pain have tender, shortened muscles because of an occult neuropathy of the segmental nerves that supply the affected skeletal muscles. The theory is consistent with Cannon's Law, a long-forgotten rule of physiology that states a neuropathy causes in this case, the end organs muscles to become more sensitive or tender. Gunn believes that during IMS the needle creates a current that makes up for the loss of muscle stimulation. Gunn has been asked to teach IMS to physicians in more than a dozen countries, and is just beginning to gain recognition from North American doctors. Once a month, he teaches his technique to pain specialists at the University of Washington. "I think it's a very interesting and provocative theory," says Loeser. "Since we've had Dr. Gunn down here, there isn't any question in my mind that patients benefit from the strategies that he uses to treat them, but not all patients. Nothing works for all patients." If today's doctors are to get a handle on chronic pain, they will probably have to develop novel theories like the one proposed by Gunn. However, that means more research is needed, and there simply aren't many researchers interested in this field. It's not a popular subject like heart disease and cancer, even though chronic pain causes more disability than cancer and heart disease combined. Some research is being done, -
mostly by psychologists and neurophysiologists. Ronald Melzack, PhD, a McGill University researcher, is exploring the complex and mysterious relationship between chronic pain and the brain. "To me, the biggest challenge lies in understanding how the brain works," he says. "We've got to understand it better if we're going to understand chronic pain. Almost all the research goes on at the level of the spinal cord, or maybe as high up as the brainstem, but above that lies a thalamus and a great big complicated cortex. We have got to start understanding that part of the brain, yet many people shy from it because it is such a complex problem." Where does one begin to look at the brain's role in creating or perpetuating chronic pain? The answer, says Melzack, is to find a clinical example in which the patient still feels pain even though the broken body part has been surgically amputated. He was first moved by the suffering of patients with phantom-limb pain more than 35 years ago. He was curious enough to spend much of his career studying the phenomenon. Phantom limb is a misnomer, because any missing body part can cause "phantom pain." When the spinal cord is cut, for instance, many patients experience a phantom body below the lesion. Women who undergo mastectomies may feel a phantom breast. Some patients with phantom bladders constantly feel the need to CAN MED ASSOC J 1991; 145 (5)
509
"Explanations for phantom-limb phenomena must, I believe, be sought in the brain. " -
Ronald Meizack, PhD
urinate. The phenomenon is far from rare - in some series, it occurs in more than 9 5% of patients who undergo amputation. Even children born without limbs may experience the sensation. Are they fantasizing? Melzack says no, because the phantom limb described by the children is usually deformed. If phantom-limb experiences are fantasies, why don't the children fantasize about intact limbs? The McGill researcher is fascinated by the uncanny way the phantom limb is incorporated into the person's sense of physical self. For example, a quadriplegic who experiences phantom phenomena in the lower body may experience moments when the hips feel as if they are being extended. "Explanations for phantom-limb phenomena must, I believe, be sought in the brain," Melzack wrote recently. In the past, most researchers believed that maintenance of a sense of the physical self results from learned behaviour. Melzack suggests we're born with it. "It seems more likely that a genetically built-in matrix of neurons for the whole body produces characteristic nerve-impulse patterns for the body and the myriad somatosensory qualities we feel," he wrote. He envisions a network of neurons whose synapses, interconnections and spatial distribution are predetermined by genetics. He calls this a "neuromatrix," whose cells and connections are distrib512
CAN MED ASSOC J 1991; 145 (5)
uted throughout the brain. It is sculpted by sensory inputs; output signals are sent to the limbic system and other areas of the brain for further processing. Melzack refers to the resultant pattern of neuronal inputs and outputs as a "neurosignature." He hypothesizes that phantom-limb pain occurs because the neuromatrix, deprived of its usual modulating inputs from the periphery, produces an abnormal signature pattern that is the neurochemical equivalent of pain, or perhaps the memory of pain. "Sometimes it may even be a memory trace of a prior pain," he adds, and wonders whether the same process is at the root of other kinds of chronic pain. "I have proposed that there is a neuromatrix that underlies a great deal of pain. I have looked for ways to try and stop activity in that neuromatrix." In animal experiments, Melzack and his colleagues have shown that injections of lidocaine into appropriate areas of the brain, such as the limbic system, decrease the amount of experimentally induced pain experienced by the animal. This new way of thinking is already bearing fruit for patients with phantomlimb pain. "If people undergoing an amputation have the nerves from the limb to the spinal cord anesthetized before the amputation, for days if necessary, they have less of a chance of having phantom-limb pain than people who do not have similar blocks."
Other scientists are looking at ways the nervous system may act to convert acute pain into chronic pain. When a person experiences acute pain after stubbing a toe, pain messages fire up the pain circuits and zip through spinal interneurons to the brain. Usually the pain circuits shut off, but with chronic pain they do not. "There is the intriguing possibility that chronic pain involves a learning process in the nervous system," says Pomeranz. "If you have repeated pain inputs coming into the nervous system, they in some way become engraved or carved in stone, so the pain persists long after the lesion is gone. The pain circuits are firing by themselves - they don't even need inputs from the diseased organ anymore." Pomeranz believes it may be possible to "unlearn" chronic pain, and thinks he may have found the neurochemical mediators to do this, the group of endogenous pain-relieving chemicals known as endorphins. "We've done some experiments recently showing that there is a memory in the endorphin system," he adds. Interestingly, the memory effect seems to occur only when the endorphins are released naturally by the body. If correct, his hypothesis could have far-reaching implications. "It means that the painrelieving system has a -memory, just like the pain itself. Any circuits that are used often enough become stronger. It is analogous to a muscle - if you work a muscle on a Nautilus machine, the first few times it hurts like hell. After a while, your strength increases and you have better muscles to show for it.?' Psychologists are also interested in learning the mechanisms of chronic pain, but instead of examining inherited factors they study it as a consequence of learning. It is known that the experience of pain is modified by emotions, LE I er SEPTEMBRE 1991
memories and learning. Psychologists are trying to tap into the brain circuits that modify pain. Dr. Patricia McGrath, a psychologist who researches pain in children, is director of the Child Health Research Institute at the Children's Hospital of Western Ontario in London, and a leading proponent of this new thinking. "Presumably, we all have the same wiring," she says. "What's different are the memories, emotions and experiences that each individual accumulates." McGrath wonders whether the seeds of chronic pain actually begin in childhood. As part of her research, she designed a simple experiment: she had a group of healthy children and a group with chronic pain keep diaries for 1 month. They recorded any pain felt. "A healthy child may experience four to six acute pains per month, and maybe one headache or stomach ache," says McGrath. "On the other hand, some of the children we see here for specialized pain problems will turn in diaries with as many as 20 to 30 pains in a month. Very few will be acute - most might be headaches and abdominal [pains]. "I was very surprised to see the numbers of 4- and 5-year-olds referred here for migraine headaches," she adds. "I'm equally surprised at the number of 12-year-olds who report that they have endured these relatively unpredictable bouts of headache for as long as 5 or 6 years. "What we start to see in the adolescent group are children who not only report headaches that started at age 6 or 7, but also a variety of limb pains, abdominal pains and back pains. To some extent, I think this group of children might be a subset of the adults who go on to have major chronic-pain problems. We need to identify them earlier in childhood, when we may be able to manage them more effectively." SEPTEMBER 1, 1991
"Most people like to be on the bandwagon. These days, chronic pain isn 't part of the bandwagon. " - Ronald Meizack, PhD
McGrath says it will take further research to determine why some children report more episodes of debilitating pain than others. "They are children who have, to some extent, been treated by the old assumption that when pain occurs, it's due to a disease," says McGrath. In this case, parents teach children to keep searching for a cause. They often drag these children from specialist to specialist in a futile attempt to find a broken part that does not exist. McGrath says that when the broken part isn't found, parents become even more anxious about their child's pain; the children sense the anxiety, and their headaches become worse. It's a vicious circle: more pain means more anxiety, and more anxiety means more pain. "We have parents seeking a cause and a cure, yet what we have is a chronic condition in childhood that's similar to the chronic pain we see in adults," says McGrath. "In fact, there is a multitude of contributing factors. No one single intervention nor magic pill exists. Unless we're smart and address each of the factors, we'll never get those children better." Fortunately, it's possible to help a substantial number of children with chronic pain. McGrath and her colleagues use a variety of nondrug therapies to treat children with recurrent headaches. They are teaching children to "unlearn" the anxiety that magnifies
their pain by using techniques such as biofeedback, relaxation training and visualization of stressful situations. McGrath says about 95% of children who learn biofeedback and relaxation training get fewer headaches. McGrath says children are much more open to these techniques than adults. "If somebody has endured pain a long time and has tried a variety of surgical and physical techniques that haven't worked, [he] would have low expectations that a nondrug treatment will work," she told CMAJ. "If I'm working with a 4-year-old, that child comes to me without a bias that only something 'powerful' like a drug, or surgery, or a machine, will reduce the pain. This makes them more open to a wide range of practical techniques for reducing pain." From my own experience as a physician, I know that is true. Many adult patients I see have more faith in pills and surgery than in other kinds of treatments, but if we're ever going to "cure the incurable," everyone pamust tients and doctors alike do some rethinking. More researchers are needed, but Melzack says few scientists are interested in chronic pain. "Most people like to be on the bandwagon," he muses, "because you get your research money and you get your promotions by being on the bandwagon. "These days, chronic pain isn't part of the bandwagon."CAN MED ASSOC J 1991; 145 (5)
513
~
~
~
~
~
~
~
~
HEALTH CARE * LES SOINS
Chronic pain and the search for alternative treatments Brian Goldman, MD
This is the last article in a threepart series on chronic pain (the first two appeared in the June I and June 15 issues). Here, Dr. Brian Goldman looks at some of the nondrug treatments being used to treat chronic pain. W r ould x
Hippocrates
be
satisfied with the way today's physicians treat chronic pain? Probably not. Nothing we do is entirely free of harm, our surgical treatments often fail to work and the drugs we prescribe may produce harmful side effects. Although conventional treatments, from orthopedic surgery to neurosurgery and psychotherapy, do have roles to play in treating chronic pain, none is a panacea. This is causing a growing number of physicians to seek alternative methods of treatment. "Alternative therapy" is, of course, a medical cussword. To some doctors it means potentially useful but untested; to others, quackery. There are numerous alternative therapies for treating chronic pain, everything from chiropractic to transcutaneous electrical nerve stimulation and acupuncture. Brian Goldman, a Toronto emergency physician, is a CMAJ contributing editor. 508
CAN MED ASSOC J 1991; 145 (5)
Acupuncture, which generally involves the insertion of hair-like needles into the body's "trigger points," produces an aching sensation and also causes stimulation of specific nerve fibres. This apparently sends the brain a signal, causing it to release pain-relieving endorphins. "The name of the game for pain is to produce a mild ache, not at the painful site but somewhere in the body," says Dr. Bruce Pomeranz, a neurophysiologist at the University of Toronto who has been studying the use of electroacupuncture to treat chronic pain. "It's not unlike the ache you get when jogging." With electroacupuncture, an electrical current is applied to the acupuncture needles to intensify the effect; Pomeranz has developed a device that produces acupuncture's effect without using needles, and patients can use it in their homes. He says electroacupuncture produces its best results in patients with osteoarthritis, although it has helped ones with aches in the back, head and neck. "There doesn't seem to be any pains that aren't helped," he says. Dr. John Loeser disagrees. "I think it's a relatively innocuous treatment with low health hazards that lacks any kind of scientific validity whatsoever," the director of the Multidisciplinary Pain Cen-
ter at the University of Washington in Seattle says. "It may provide benefit to people with certain types of musculoskeletal disorders, but those who say it is a treatment with specific beneficial effects should produce the evidence. "All of the studies done show acupuncture has a mild analgesic effect which is unlikely to be of major benefit for most people. It also has a tremendous psychologic effect because there is a treating person and a treating technology. Studies looking carefully at these issues have simply failed to demonstrate that this is a very effective method of treating people with chronic pain." Pomeranz says many studies are being ignored by the sceptics. "We know a lot more about how electroacupuncture works than about a lot of standard medical procedures," he contends. "For example, we don't know how gaseous anesthetics work but we use them all the time because empirically they work." As the acupuncture debate continues, an east-west meeting of the minds is taking place at the Gunn Pain Clinic in Vancouver. Here, a Canadian physician has fused oriental acupuncture with western concepts of neurophysiology to produce a pain-management technique that is surprising-
ly effective. LE I er SEPTEMBRE 1991
Intramuscular stimulation (IMS) was developed in Vancouver in the early 1970s by Dr. Chit-Chan Gunn, then a staff physician at the Workers' Compensation Board of British Columbia (WCB), where he had become interested in the plight of workers disabled by severe back pain. Gunn and his colleagues studied patients with low back pain who did not return to work and compared them with patients who did. They found a subtle, reproducible difference. Patients unable to resume work had numerous skeletal muscles whose fibres were shortened and tender when palpated; those who returned to work tended to have normal skeletal muscles. This observation was the first piece in a puzzle that led to Gunn's discovery of IMS. In 1973, the WCB asked him to write a report on acupuncture. He observed the technique in China, but was unimpressed. "The Chinese doctors did not have a physiological basis to explain acupuncture - they were more or less using it as a recipe from a cookbook." The board then sent Gunn to New York City to train in electromyography (EMG). On his return, he inserted EMG needles into the muscles overlying traditional acupuncture points to study the electrical activity; at times he used an electrical current to stimulate the region. "As we were sticking needles into certain points, such as the motor point or muscle-tendon junction, we found that the muscles began to relax," recalls Gunn. "I was really astonished when I treated a patient at the WCB who had low back pain for months. When I did an EMG examination followed by stimulation through the needle, the man came to me the next day and said that his pain was completely gone and he was returning to work. Incidents like that convinced me this was a technique worth studying." SEPTEMBER 1, 1991
"The name of the game for pain is to produce a mild ache, not at the painful site, but somewhere in the body. " -
Dr. Bruce Pomeranz
Gunn believes many patients with chronic pain have tender, shortened muscles because of an occult neuropathy of the segmental nerves that supply the affected skeletal muscles. The theory is consistent with Cannon's Law, a long-forgotten rule of physiology that states a neuropathy causes in this case, the end organs muscles to become more sensitive or tender. Gunn believes that during IMS the needle creates a current that makes up for the loss of muscle stimulation. Gunn has been asked to teach IMS to physicians in more than a dozen countries, and is just beginning to gain recognition from North American doctors. Once a month, he teaches his technique to pain specialists at the University of Washington. "I think it's a very interesting and provocative theory," says Loeser. "Since we've had Dr. Gunn down here, there isn't any question in my mind that patients benefit from the strategies that he uses to treat them, but not all patients. Nothing works for all patients." If today's doctors are to get a handle on chronic pain, they will probably have to develop novel theories like the one proposed by Gunn. However, that means more research is needed, and there simply aren't many researchers interested in this field. It's not a popular subject like heart disease and cancer, even though chronic pain causes more disability than cancer and heart disease combined. Some research is being done, -
mostly by psychologists and neurophysiologists. Ronald Melzack, PhD, a McGill University researcher, is exploring the complex and mysterious relationship between chronic pain and the brain. "To me, the biggest challenge lies in understanding how the brain works," he says. "We've got to understand it better if we're going to understand chronic pain. Almost all the research goes on at the level of the spinal cord, or maybe as high up as the brainstem, but above that lies a thalamus and a great big complicated cortex. We have got to start understanding that part of the brain, yet many people shy from it because it is such a complex problem." Where does one begin to look at the brain's role in creating or perpetuating chronic pain? The answer, says Melzack, is to find a clinical example in which the patient still feels pain even though the broken body part has been surgically amputated. He was first moved by the suffering of patients with phantom-limb pain more than 35 years ago. He was curious enough to spend much of his career studying the phenomenon. Phantom limb is a misnomer, because any missing body part can cause "phantom pain." When the spinal cord is cut, for instance, many patients experience a phantom body below the lesion. Women who undergo mastectomies may feel a phantom breast. Some patients with phantom bladders constantly feel the need to CAN MED ASSOC J 1991; 145 (5)
509
"Explanations for phantom-limb phenomena must, I believe, be sought in the brain. " -
Ronald Meizack, PhD
urinate. The phenomenon is far from rare - in some series, it occurs in more than 9 5% of patients who undergo amputation. Even children born without limbs may experience the sensation. Are they fantasizing? Melzack says no, because the phantom limb described by the children is usually deformed. If phantom-limb experiences are fantasies, why don't the children fantasize about intact limbs? The McGill researcher is fascinated by the uncanny way the phantom limb is incorporated into the person's sense of physical self. For example, a quadriplegic who experiences phantom phenomena in the lower body may experience moments when the hips feel as if they are being extended. "Explanations for phantom-limb phenomena must, I believe, be sought in the brain," Melzack wrote recently. In the past, most researchers believed that maintenance of a sense of the physical self results from learned behaviour. Melzack suggests we're born with it. "It seems more likely that a genetically built-in matrix of neurons for the whole body produces characteristic nerve-impulse patterns for the body and the myriad somatosensory qualities we feel," he wrote. He envisions a network of neurons whose synapses, interconnections and spatial distribution are predetermined by genetics. He calls this a "neuromatrix," whose cells and connections are distrib512
CAN MED ASSOC J 1991; 145 (5)
uted throughout the brain. It is sculpted by sensory inputs; output signals are sent to the limbic system and other areas of the brain for further processing. Melzack refers to the resultant pattern of neuronal inputs and outputs as a "neurosignature." He hypothesizes that phantom-limb pain occurs because the neuromatrix, deprived of its usual modulating inputs from the periphery, produces an abnormal signature pattern that is the neurochemical equivalent of pain, or perhaps the memory of pain. "Sometimes it may even be a memory trace of a prior pain," he adds, and wonders whether the same process is at the root of other kinds of chronic pain. "I have proposed that there is a neuromatrix that underlies a great deal of pain. I have looked for ways to try and stop activity in that neuromatrix." In animal experiments, Melzack and his colleagues have shown that injections of lidocaine into appropriate areas of the brain, such as the limbic system, decrease the amount of experimentally induced pain experienced by the animal. This new way of thinking is already bearing fruit for patients with phantomlimb pain. "If people undergoing an amputation have the nerves from the limb to the spinal cord anesthetized before the amputation, for days if necessary, they have less of a chance of having phantom-limb pain than people who do not have similar blocks."
Other scientists are looking at ways the nervous system may act to convert acute pain into chronic pain. When a person experiences acute pain after stubbing a toe, pain messages fire up the pain circuits and zip through spinal interneurons to the brain. Usually the pain circuits shut off, but with chronic pain they do not. "There is the intriguing possibility that chronic pain involves a learning process in the nervous system," says Pomeranz. "If you have repeated pain inputs coming into the nervous system, they in some way become engraved or carved in stone, so the pain persists long after the lesion is gone. The pain circuits are firing by themselves - they don't even need inputs from the diseased organ anymore." Pomeranz believes it may be possible to "unlearn" chronic pain, and thinks he may have found the neurochemical mediators to do this, the group of endogenous pain-relieving chemicals known as endorphins. "We've done some experiments recently showing that there is a memory in the endorphin system," he adds. Interestingly, the memory effect seems to occur only when the endorphins are released naturally by the body. If correct, his hypothesis could have far-reaching implications. "It means that the painrelieving system has a -memory, just like the pain itself. Any circuits that are used often enough become stronger. It is analogous to a muscle - if you work a muscle on a Nautilus machine, the first few times it hurts like hell. After a while, your strength increases and you have better muscles to show for it.?' Psychologists are also interested in learning the mechanisms of chronic pain, but instead of examining inherited factors they study it as a consequence of learning. It is known that the experience of pain is modified by emotions, LE I er SEPTEMBRE 1991
memories and learning. Psychologists are trying to tap into the brain circuits that modify pain. Dr. Patricia McGrath, a psychologist who researches pain in children, is director of the Child Health Research Institute at the Children's Hospital of Western Ontario in London, and a leading proponent of this new thinking. "Presumably, we all have the same wiring," she says. "What's different are the memories, emotions and experiences that each individual accumulates." McGrath wonders whether the seeds of chronic pain actually begin in childhood. As part of her research, she designed a simple experiment: she had a group of healthy children and a group with chronic pain keep diaries for 1 month. They recorded any pain felt. "A healthy child may experience four to six acute pains per month, and maybe one headache or stomach ache," says McGrath. "On the other hand, some of the children we see here for specialized pain problems will turn in diaries with as many as 20 to 30 pains in a month. Very few will be acute - most might be headaches and abdominal [pains]. "I was very surprised to see the numbers of 4- and 5-year-olds referred here for migraine headaches," she adds. "I'm equally surprised at the number of 12-year-olds who report that they have endured these relatively unpredictable bouts of headache for as long as 5 or 6 years. "What we start to see in the adolescent group are children who not only report headaches that started at age 6 or 7, but also a variety of limb pains, abdominal pains and back pains. To some extent, I think this group of children might be a subset of the adults who go on to have major chronic-pain problems. We need to identify them earlier in childhood, when we may be able to manage them more effectively." SEPTEMBER 1, 1991
"Most people like to be on the bandwagon. These days, chronic pain isn 't part of the bandwagon. " - Ronald Meizack, PhD
McGrath says it will take further research to determine why some children report more episodes of debilitating pain than others. "They are children who have, to some extent, been treated by the old assumption that when pain occurs, it's due to a disease," says McGrath. In this case, parents teach children to keep searching for a cause. They often drag these children from specialist to specialist in a futile attempt to find a broken part that does not exist. McGrath says that when the broken part isn't found, parents become even more anxious about their child's pain; the children sense the anxiety, and their headaches become worse. It's a vicious circle: more pain means more anxiety, and more anxiety means more pain. "We have parents seeking a cause and a cure, yet what we have is a chronic condition in childhood that's similar to the chronic pain we see in adults," says McGrath. "In fact, there is a multitude of contributing factors. No one single intervention nor magic pill exists. Unless we're smart and address each of the factors, we'll never get those children better." Fortunately, it's possible to help a substantial number of children with chronic pain. McGrath and her colleagues use a variety of nondrug therapies to treat children with recurrent headaches. They are teaching children to "unlearn" the anxiety that magnifies
their pain by using techniques such as biofeedback, relaxation training and visualization of stressful situations. McGrath says about 95% of children who learn biofeedback and relaxation training get fewer headaches. McGrath says children are much more open to these techniques than adults. "If somebody has endured pain a long time and has tried a variety of surgical and physical techniques that haven't worked, [he] would have low expectations that a nondrug treatment will work," she told CMAJ. "If I'm working with a 4-year-old, that child comes to me without a bias that only something 'powerful' like a drug, or surgery, or a machine, will reduce the pain. This makes them more open to a wide range of practical techniques for reducing pain." From my own experience as a physician, I know that is true. Many adult patients I see have more faith in pills and surgery than in other kinds of treatments, but if we're ever going to "cure the incurable," everyone pamust tients and doctors alike do some rethinking. More researchers are needed, but Melzack says few scientists are interested in chronic pain. "Most people like to be on the bandwagon," he muses, "because you get your research money and you get your promotions by being on the bandwagon. "These days, chronic pain isn't part of the bandwagon."CAN MED ASSOC J 1991; 145 (5)
513
