WHO WILL STOP THE PAIN?

Part 2:

Canada Leads Research Revolution

Three months after breaking the fourth cervical vertebra in his neck
in a freak hockey accident at the age of 17, Kurt Gengenbach began
experiencing a new and spectacular kind of torment.

He started feeling pain in his left pectoral muscle -- a constant
burning, pinsand-needles sensation that slowly spread to his right
shoulder, across his chest, down into his abdomen and finally through
his legs and into his feet.

Gengenbach is a quadriplegic. He cannot move his arms or his legs. But
he can feel pain. His ankles feel as if they're bound in thick,
bone-crushing casts. A Kleenex against his bare shoulder can feel like
a blowtorch. The skin on his chest is so hypersensitive he can't
breathe deeply to relax when the pain hits, the way his therapist told
him to, because expanding his chest makes his skin stretch, and it's
torture. "Basically I'm paralyzed by pain," he says.

The tragic irony -- that a body that can't even move is still racked by
continuing pain -- is compounded, Gengenbach says, by the fact that
sometimes people don't believe him.

Some of his attendants know that just moving his arm or touching him
can be painful. "Others think, 'It can't hurt him that much,' and they
just kind of throw me around," the Toronto resident says. "They don't
believe it."

Canadian researchers are trying to stamp out once and for all the
skepticism faced by many who suffer severe, persistent pain. The
revolution in research Canadians are helping to lead is aimed at
showing just how real pain is.

Researchers are using high-tech imaging to show the human brain in the
act of processing pain. They're discovering how unrelenting, day-in
and day-out pain can change the brain's anatomy (pain shrinks the
brain in some areas) and how those abnormal changes can be reversed
with successful treatment. They're discovering just how often poorly
treated pain after surgery morphs into chronic pain that can last for
years.

In Quebec, 3,500 patients are being followed in what is believed to be
the largest registry of chronic-pain patients in the world -- a massive
undertaking that could unlock answers to one of the most universal of
all human experiences, including what factors predispose us to chronic
pain, and what perpetuates it.

The goal across this research spectrum is to reduce suffering and
banish the idea that pain that doesn't respond to treatment -- or that
seems wholly out of sync with any physical finding -- isn't genuine.

"There is a huge social change that is happening," says Dr. Fernando
Cervero, director of the Alan Edwards Centre for Research on Pain at
Mcgill University, one of the world's leading pain research centres.
"We are in a way leading, but also society is leading it. People are
saying, 'Why do we have to live with pain?' "

Scientists have long been searching for an objective way to measure
pain -- using heart rate, blood pressure, temperature changes, muscle
tension, and skin sweating. These physiological "markers" can work for
short, sharp pain, but not chronic pain.

Now, researchers are taking the first steps toward developing a tool
to detect pain based on patterns of human brain activity. The most
recent experiments involve functional MRIS. Normal MRIS take pictures
of the structure of the brain; FMRIS take a series of pictures showing
what activity is going on.

In a study reported in September, Stanford University School of
Medicine researchers put people inside the brain-scanning machines,
applied a heat probe to their arms, then looked at the brain patterns
both with and without heat. The brain patterns were recorded and
interpreted by computer algorithms to create a model of what pain -- in
this case, mild pain in a carefully controlled lab setting -- looks
like.

The next step is to see whether the same method can be used to measure
chronic pain.

"The issue of validation of pain is a critical one," said senior
author Dr. Sean Mackey, chief of the division of pain management at
Stanford.

"They don't feel like they've been believed, they feel as if their
physicians and friends and families think the pain is not real.
They're desperately looking for a way to prove to people that they do
have pain."

Mackey said he would like to think this technology isn't needed, that
doctors could and should be educated that pain is real, that it's a
"neurophysiologic phenomenon" -- that it is whatever the patient says
it is. For generations, the prevailing theory on how pain works was
straightforward: in response to injury or disease, special pain
receptors or nerve fibres in the skin, muscle, joints and other
tissues act like a shrill alarm. The alarm sends pain signals through
the spinal cord up into a pain centre in the cerebral cortex, where we
were thought to "feel" pain.

"The metaphor we use is ringing the bell," says Dr. Lori Montgomery,
medical director of the Calgary Chronic Pain Centre. Pull the cord and
the bell rings. That was the old model. More recent research tells us
that pain is much more complex than we ever imagined, she says.

"There are many nerve pathways, and many different mechanisms that
decide whether that alarm signal will make it to the brain or not."

Pain is a survival mechanism. Humans need to feel acute pain -- sudden
bursts of pain from an injury -- in order for the species to thrive.
Acute pain tells the brain something is wrong.

Chronic pain doesn't serve the same survival function. It can occur
when the alarm gets stuck "on," even after the fire is out. The nerves
keep shooting pain signals up to the brain, as if the tissues were
still being damaged. The bell is ringing for no apparent reason,
Calgary's Montgomery says, "or there may be a reason, but we don't
understand what it is."

Not only do the pain signals spontaneously fire, they'll now respond
to stimuli, says Dr. Mary Lynch, director of the Pain Management Unit
at the Queen Elizabeth II Health Sciences Centre in Halifax. Things
that shouldn't be harmful -- even a light touch -- can cause
excruciating pain.

But what happens when there is no physical explanation, no "organic
basis" to account for the pain?

"You can take a picture of somebody's spine and it looks absolutely
normal and perfect, and yet they have horrible pain. So where is the
pain?" asks renown pain researcher Dr. Ronald Melzack, professor
emeritus of psychology at McGill University.

"That's the pain we need to start concentrating on."

Pain, he says, used to get three pages in the medical textbooks. Pain
was a sensation, he says, "it didn't mean suffering." Nearly 40 years
ago, Melzack helped put a language to pain with the McGill Pain
Questionnaire, a tool now used the world over to assess pain. It
consists of 78 pain descriptors -- words such as pounding, drilling,
quivering, stabbing, shooting, exhausting, sickening, suffocating -- to
try to describe suffering. Each is rated on a five-point scale -- the
higher the pain score, the greater the pain.

But it was his "gate control" theory of pain that revolutionized pain
science.

In 1965, Melzack and his colleague, MIT neuroscientist Patrick Wall,
published a theory that challenged the idea that there was a one-way,
skin-to-brain "pain pathway."

Instead, their gate-control theory argued that nerve cells in the
spinal cord act like miniature gates that can block pain signals from
getting through and up into the brain, or allow them in.

Melzack once explained it this way: "If you are playing hockey and get
kicked in the shin, your gates are often closed because your brain
isn't interested in pain at that time." (Kurt Gengenbach once skated
an entire game of hockey on a broken ankle. He didn't realize the bone
was broken until he took his skate off.)

"On the other hand, " Melzack said, "if you have a slight stomach ache
and you learn that a friend has just died of stomach cancer, suddenly
the gates are opened, and you may have terrible abdominal pain."

Melzack has expanded his hypothesis since. He says humans are born
with genetically determined neural networks, which are pain-processing
programs in our brains that can be influenced by mood, emotions,
memories and other sensory experiences.

This "neuromatrix" can be activated by an injury or illness, he says.
But it can also go off spontaneously.

Experts say that how we think about pain can affect how we feel pain
and, for some, the urge is to "catastrophize" the pain -- "this pain
will never go away, I will never be able to handle this."

Attention can also have a significant impact on pain and pain
processing, says Dr. Catherine Bushnell, professor of anesthesia at
McGill University in Montreal and president of the Canadian Pain Society.

In studies of healthy volunteers who were subjected to experimental
pain -- heat not hot enough to cause a blister but hot enough to
activate the person's pain system -- Bushnell's team has found that
people rate their pain higher when they're focusing on it. "When
you're distracted, you feel less pain."

Emotions modulate pain differently, she says. When people experience
positive emotions, "they still feel pain, they still rate it with the
same intensity, but it bothers them less, it's less unpleasant," says
Bushnell. "These are ways that you can engage in and work on your own
therapy."

For 12 years, Kurt Gengenbach watched helplessly as pain took over his
body, as more and more parts started hurting.

Gengenbach was paralyzed during a senior high school hockey game, when
he went in for a hit, lost the edge of his skate and slammed headfirst
into the boards.

Today he suffers from neuropathic pain. With a spinal cord injury,
sensory nerves at the level of the injury are also damaged, causing
changes in their electrical signalling. Some of those damaged nerves
get stuck in the "on" setting, so the pain signals keep firing.

Gengenbach has been living with pain for 22 years. "You don't get used
to it, you just learn to deal with it," he says. The most difficult
thing, he says, is frustration with people not understanding the pain.

He has a medicinal marijuana licence. Marijuana helps control his pain
by controlling the muscle spasms. Yet, some of his attendants refuse
to hold his pipe for him, saying they have a right to work in a
smoke-free environment. Gengenbach has disposable surgical masks that
would cover their face entirely. He takes only one puff at a time from
a small bowl pipe. The amount of smoke, he says, is miniscule.

At night, he sometimes lies awake in agony. He can see his pipe next
to his bed when he turns his head, but he can't reach out and grab it.
It's right there, right beside him. "I can see it. But I can't get
it.

"I sometimes beg for the ability to make someone feel my pain for five
or 10 seconds," he says. "I feel bad for saying that. . . . It's very
hard for people to understand.

"My pain dictates my life much more than my disability ever has."