FEATURE STORY/ WHEN THE NERVOUS SYSTEM PANICS
study’s discussion section, “we assumed
that SMT-evoked supraspinal effects
would impact pain sensitivity at both
trigger points comparably.” The study
only showed significant changes at
the segmentally linked trigger point,
indicating segmental rather than
supraspinal mechanisms. Researchers
continue to examine whether SMT’s
effect is predominantly regional, general
or a combination of the two.
This study showed a significant
difference in pain thresholds in the
infraspinatus (as compared to the gluteus
medius) at 3 and 5 minutes, suggesting
that dry needle stimulation can evoke
short-term pain reduction within a
neurological segment.
This was not a surprise to Dr.
Srbely. He points out that the World
Health Organization’s list of diseases
and disorders that can be treated with
acupuncture is multi-systemic in scope.
If SMT proves to be an effective modulator of
C-Sens, this may open up a significant role in
our health care system for chiropractors as the
gate-keepers of clinical conditions associated
with C-Sens, such as myofascial pain syndrome.
Other Manual Therapies
S
pinal manipulative therapy is not the
only mechanism proposed to ease
C-Sens. Several other therapies
have also shown promise in this area.
Acupuncture
D
r. Srbely’s team performed a
very similar study in 2010 that
examined the effect of dry
needle stimulation of myofascial trigger
points, again by comparing trigger
points in the infraspinatus and gluteus
medius muscles. Rather than receiving
SMT, subjects in this study received
intramuscular dry needle puncture at a
right supraspinatus trigger point which is
neurologically linked to the infraspinatus
muscle at C5.
14
SPRING 2015
Controlled trials have shown significant
scientific support for acupuncture
treatment of conditions including colic,
headache, neck pain, low back pain,
stroke, morning sickness and depression.
“There must be a common mechanism
that is linking all of these conditions,”
Dr. Srbely says. “When I started digging
deeper into this, my hypothesis began to
emerge: central sensitization.”
Ultrasound
D
r. Srbely’s team performed
a similar study in 2008
which examined the effect of
ultrasound, again by comparing trigger
points in the infraspinatus and gluteus
medius muscles. Test subjects in this
study received low-dose ultrasound to
a right supraspinatus (C5) trigger point
while control subjects received a sham
ultrasound exposure.
Significant difference in pain
thresholds were found in the
infraspinatus (as compared to the
gluteus medius) at 1, 3 and 5 minutes,
demonstrating that ultrasound can
evoke short-term pain reduction within a
segment.
And More
I
f the above modalities are using gate
control to reduce C-Sens, it is very
possible that this same mechanism
may also be responsible for the
therapeutic effects observed with active
release therapy, massage therapy,
exercise, movement and more.
Remaining Research
Questions
W
hile there is now enough
research data to begin
connecting the dots, several
outstanding areas of research still
remain. These questions will need to
be understood in more depth before
chiropractors can use this research to
guide patient care or to make claims
for the effectiveness of SMT for specific
conditions.
Current research questions include:
∞∞ How should patients with C-Sens be
identified in the clinic? How should
their care differ? Do sensitized
patients require a gentler approach to
avoid aggravating their sensitivity to
pain input?
∞∞ Why might C-Sens affect some
patients more than others?
∞∞ How can we measure the degree of
central sensitization? This is important
both for clinicians caring for patients