R.S.D. Article # 2

Complex regional pain syndrome
The first question is: what do we call it? While many doctors may still use
the RSD label, there has been some agreement to change the name to reflect
new doubts about old theories. The disorder was once thought to be a
malfunctioning of the sympathetic nervous system, based on a reflex and
causing dystrophy. Some experts now believe this chronic pain may not be
related to the sympathetic nervous system at all, and may not be related to a
reflex, and they have succeeded in getting the name changed.

Now, the words "complex regional pain syndrome" (CRPS) encompass both what
used to be RSD and what used to be called causalgia. Under the umbrella of
CRPS, these two are distinguished because Type I includes no evidence of
nerve damage (RSD) and Type II has evidence of physical nerve damage
(causalgia).

"The term RSD has lost usefulness as a clinical designation because it has
been used so indiscriminately that it is no longer clear what it means,"
wrote conference participants in the journal Pain.

The disorder is increasingly being diagnosed in association with cumulative
trauma disorders, according to Howard Sandler, M.D., who heads an
occupational medicine firm in New York.

There are a variety of reasons why the diagnosis is surging, according to
Sandler, who wrote about it in a 1994 article for Occupational Hazards. Among
the reasons he offered: increased physician awareness of the diagnosis,
workers' compensation cost shifting, procedure-oriented medical practice,
absence of clinical practice guidelines and the growth of the pain center
industry.

To understand the industry surrounding pain, it is helpful to know more about
nerve blocks, one of the procedures often used as part of diagnosis or
treatment for RSD.

In a block, a doctor injects an anesthetic drug near one of the nerves
suspected of causing the pain. If the patient gets relief, the doctor may
assume this nerve is partly to blame. Some doctors believe nerve blocks can
confirm the diagnosis. Other doctors point to studies where patients
receiving a sham nerve block, or placebo, reported just as much pain relief
as those who received the real drug.

Whether or not you accept nerve blocks as a diagnostic tool, or a treatment
option, they are a growing cost in claims for chronic pain. A single "block,"
administered in a hospital, may cost $250. The doctor's fee may double that.
A course of treatment may require 20 blocks, for a cost of more than $10,000.

Most patients who have RSD have it in an arm or leg. Experts agree that
keeping that limb mobile is vitally important to treating this disorder. By
eliminating pain, the doctor hopes to help the patient keep moving the limb,
and often physical therapy is coordinated with the nerve blocks.

"Blocks or no blocks, one thing no one will disagree with is that the
hallmark of treatment is promoting full range of motion and active use of the
affected extremity," explained Edgar Steinitz, M.D., a Tacoma, Wash.,
physiatrist. Physiatrists are a special branch of medical doctors who focus
on rehabilitation. Steinitz pointed out that a treatment plan taking both
physical and psychological needs into consideration is the best way to
prevent disability.

Theory
The traditional theory of how RSD works holds that damage to a peripheral
nerve causes a malfunctioning of other nerve fibers. These fibers misfire in
some way, creating a burning pain, as well as an abnormally hot or sometimes
cold hand.

The misfiring fibers are part of what is called the sympathetic nervous
system, which is responsible for a host of body functions that people do not
consciously control. For example, the sympathetic system regulates the body's
temperature by constricting blood vessels. The sympathetic system has a twin
system, known as the parasympathetic. Every organ of the body is served by
both sets of nerves. Together, these twin systems regulate things such as how
fast the heart beats, how much we sweat, and how rapidly our intestines
digest our food. Taken together, the two are called the autonomic nervous
system.

Many prescription drugs take advantage of the autonomic system. Drugs to
lower blood pressure, for example, block the messages of the sympathetic
system to reduce the rate and force of the heart beat.

But, even though medicine understands some of what these nerves do, the
physiology of the nervous system, and the biochemistry of the tiny molecules
known as neurotransmitters, is turning out to be very complex. Some
researchers report evidence that damage to peripheral nerves can lead to
permanent changes in the central nervous system, and this may explain RSD
symptoms. This idea is known as the interactionist theory.

For years, doctors found that some patients with the symptoms of RSD could
get pain relief if the sympathetic nerves to their painful arm or leg were
blocked by an anesthetic or even removed in a surgery known as sympathectomy.
This is partly why the misfiring of sympathetic nerves is suspected of
causing the characteristic symptoms: burning pain, a hand or leg that swells
(edema), hypersensitivity to touch, and eventually, a wasting of the limb.

Now, this theory is being challenged by researchers who complain that much of
the "evidence" used to build it was the subjective reports of pain relief by
patients given nerve blocks. Many studies were done without taking into
account what is called the placebo effect.

One of the leading critics is Jose Ochoa, M.D., Ph.D., a neurologist and
professor at Oregon Health Sciences University in Portland. Ochoa has written
many articles on RSD, including a 1995 chapter for Neurology Clinics
expressing the view that much of what is diagnosed as RSD is actually a
psychological disorder known as somatoform expression.

Patients diagnosed with RSD are, in his words, "not a homogeneous population;
they have any of multiple possible disorders generating what on the surface
appears to be a specific clinical expression; a majority of them have neither
nerve injury nor other organic dysfunction to explain their symptomatology."

Patients with symptoms of RSD may have other treatable disorders, such as
diabetic neuropathy, tumors on nerves, nerve entrapment or spinal cord
disease. Ochoa warns that without proper neurologic diagnosis, these patients
can be harmed by useless therapy or by omission of proper investigation for a
health disorder other than RSD.

His views have been characterized as radical by some, but one author wrote
that traditionalists concede Ochoa's premise that current care of patients is
inadequate, but they dispute his blanket rejection of established pain
management patterns.

Understanding the controversy over RSD also requires understanding the
different specialists who may be treating it. Neurologists and
anesthesiologists are probably most likely to handle the disorder, but hand
surgeons and general orthopedists may also be involved. A physiatrist, such
as Dr. Steinitz who was quoted earlier, would coordinate a constellation of
therapists and look at a variety of options for treatment.

Each specialty may see the disorder through a different lens and try to treat
it with procedures in their arsenal. As Steinitz said earlier, an approach
that takes multiple theories into consideration and includes both physical
intervention and psychological evaluation, is the best.

"The pain community has a lot at stake here in terms of credibility, status
and income," wrote Stephen McAliley, the editor of Hippocrates' Lantern, a
newsletter on legal issues of medicine. In discussing the RSD controversy,
McAliley recommended that insurers always seek out an academic neurologist
for any review of an RSD claim. Yet, in all this discussion of finances, the
patient must not be forgotten.

Early treatment
Early and precise diagnosis, and treatment to keep a limb moving, are
essential to prevent the final disability, everyone agrees. But how to be
sure of a diagnosis is difficult. A typical patient who gets RSD might
develop it after an injury in which the limb was in a cast, or after surgery
for some other condition, such as carpal tunnel syndrome.

No one test will identify RSD, although there are some tests that are helpful
in ruling it out. A thorough medical history and a careful physical
examination are essential. The presence of objective signs and consistency of
symptoms are also important. Doctors may observe differences in skin
temperature or blood flow between the affected and unaffected limbs.

X-rays can be helpful by showing bone loss in the affected limb, but
sometimes these are not useful early in the course of the disorder. A special
test known as a triple-phase bone scan uses an injected substance to reveal
blood flow in the limb, and has been reported as helpful by some researchers
and misleading by others.

Nerve blocks have been a mainstay of diagnosis for many years, and are
routinely used to block pain in order to allow movement of the limb and
prevent atrophy. Because the doctor has no way to measure the pain relief,
except the patient's report, a successful block by itself does not confirm a
diagnosis. Taken together with the rest of the clinical picture, the block
results are enough for many doctors to diagnose the disorder.

Some of the treatments used include: a short course of oral steroids, given
early in the course of the disease; injections of anesthetic drugs to block
nerves suspected of causing pain; physical therapy to keep limbs moving and
prevent atrophy; psychological therapy; surgical cutting of sympathetic
nerves, called sympathectomy; and a multidisciplinary approach from a pain
clinic.

Almost all of these treatments can vary in effectiveness, depending on how
they are administered and how accurately the diagnosis was made in the first
place. There are many different ways to administer a nerve block, different
drugs and combinations, and different techniques for placing the needle. How
doctors reach a diagnosis, and how they administer blocks can make a
difference in the effectiveness of the treatment.

Conclusion
Does it seem as if no one agrees about anything in this diagnosis? Wrong.
They all agree that more objective information on pain would help.

Writing about Ochoa's radical suspicions of the traditional view, a group of
doctors writing in Hand Surgery Update express common ground with him.

"In this controversy, a commonality of purpose exists: promotion of
objectivity in the management of patients with pain." Comparing results
between therapies requires very careful focus that makes sure the patients
compared are apples to apples, not apples to oranges. When doctors have to
rely on patients' reports of pain as bad, very bad, or better, they have no
"objective" way to compare.

Even as the academics may argue about the syndrome, patients need treatment.
Doctors in exam rooms need to go ahead and use what treatments they have.

"Just because we do not yet know all of the reasons that cause this
hodge-podge of similar but varied manifesting disorders, and just because
many do not respond to blocks performed by anesthesiologists, and just
because a few have serious psychiatric problems or are embroiled in the
complexities of the workers' compensation system with secondary gain, does
not mean that we should overlook those who have a very serious and at times
devastating medical condition," says Steinitz, the rehabilitation doctor.

Employers may agree with Steinitz for a more pragmatic financial reason,
because they can save money by understanding that RSD is a possibility and
its management is complex.

"All risk managers and safety and health professionals should be aware of its
possibility and incorporate a sound approach to its proper identification and
management," Sandler advised in his article.
 
 
 

Article copyright © 1999. Medical Consultants Network, Inc. All rights
reserved.