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BioMed Central
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Chiropractic & Osteopathy
Open Access
Research
Neuro Emotional Technique for the treatment of trigger point
sensitivity in chronic neck pain sufferers: A controlled clinical trial
Peter Bablis
1
, Henry Pollard*
1,2
and Rod Bonello
1
Address:
1
Macquarie Injury Management Group, Macquarie University, Sydney, Australia and
2
Director of Research, ONE Research Foundation,
Encinitas, California, USA
Email: Peter Bablis - pb@universalhealth.com.au; Henry Pollard* - hpollard@optushome.com.au; Rod Bonello - rbonello@els.mq.edu.au
* Corresponding author
Abstract
Background: Trigger points have been shown to be active in many myofascial pain syndromes. Treatment
of trigger point pain and dysfunction may be explained through the mechanisms of central and peripheral
paradigms. This study aimed to investigate whether the mind/body treatment of Neuro Emotional
Technique (NET) could significantly relieve pain sensitivity of trigger points presenting in a cohort of
chronic neck pain sufferers.
Methods: Sixty participants presenting to a private chiropractic clinic with chronic cervical pain as their
primary complaint were sequentially allocated into treatment and control groups. Participants in the
treatment group received a short course of Neuro Emotional Technique that consists of muscle testing,
general semantics and Traditional Chinese Medicine. The control group received a sham NET protocol.
Outcome measurements included pain assessment utilizing a visual analog scale and a pressure gauge
algometer. Pain sensitivity was measured at four trigger point locations: suboccipital region (S); levator
scapulae region (LS); sternocleidomastoid region (SCM) and temporomandibular region (TMJ). For each
outcome measurement and each trigger point, we calculated the change in measurement between pre-
and post- treatment. We then examined the relationships between these measurement changes and six
independent variables (i.e. treatment group and the above five additional participant variables) using
forward stepwise General Linear Model.
Results: The visual analog scale (0 to 10) had an improvement of 7.6 at S, 7.2 at LS, 7.5 at SCM and 7.1
at the TMJ in the treatment group compared with no improvement of at S, and an improvement of 0.04
at LS, 0.1 at SCM and 0.1 at the TMJ point in the control group, (P < 0.001).
Conclusion: After a short course of NET treatment, measurements of visual analog scale and pressure
algometer recordings of four trigger point locations in a cohort of chronic neck pain sufferers were
significantly improved when compared to a control group which received a sham protocol of NET.
Chronic neck pain sufferers may benefit from NET treatment in the relief of trigger point sensitivity.
Further research including long-term randomised controlled trials for the effect of NET on chronic neck
pain, and other chronic pain syndromes are recommended.
Trial Registration: This trial has been registered and allocated the Australian Clinical Trials Registry
(ACTR) number ACTRN012607000358448. The ACTR has met the requirements of the ICMJE's trials
registration policy and is an ICMJE acceptable registry.
Published: 21 May 2008
Chiropractic & Osteopathy 2008, 16:4 doi:10.1186/1746-1340-16-4
Received: 12 May 2007
Accepted: 21 May 2008
This article is available from: http://www.chiroandosteo.com/content/16/1/4
© 2008 Bablis et al; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0
),
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Chiropractic & Osteopathy 2008, 16:4 http://www.chiroandosteo.com/content/16/1/4
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Background
Trigger points have been defined as discrete, hyperirritable
foci usually located within a taut band of skeletal muscle
[1]. The point is a well-circumscribed area in which pres-
sure produces a characteristic referred pain, tenderness
and autonomic phenomena [1]. Trigger points are consid-
ered an essential defining part of the myofascial pain syn-
drome, in which widespread or regional muscular pain is
a cause of musculoskeletal dysfunction [2], as well as
being associated with hyperalgesia, restriction of daily
function or psychological disturbance [3]. Upon clinical
presentation, trigger points are classified depending on
certain characteristics. An active trigger point is defined as
one with spontaneous pain, or pain in response to move-
ment. It is tender on palpation, and may present with a
referral pattern of pain, not at the site of the trigger point
origin. A latent trigger point is a sensitive spot that causes
pain or discomfort only in response to compression. Trig-
ger points are reported to occur more frequently in cases
of mechanical neck pain than in matched controls [4].
Patients may only become aware of pain when pressure is
applied to a muscular point of restriction or weakness.
The pathogenesis of trigger points is not clear, but it is
believed they arise from more than one cause [5]. Fischer
[5] has suggested that trigger points are due to the sensiti-
sation of nerves and the tenderness results from the
decrease in the pain pressure threshold. He further opines
that the tissue damage associated with injury causes the
release of inflammatory products that increase the sensi-
tivity of the nerve to stimulation. These substances
include bradykinins, 5-HT and prostaglandins, though a
recent study found tender points in the trapezius muscle
of patients with tension-type headache were not sites of
ongoing inflammation [6]. Trigger points are also thought
to arise from acute trauma or repetitive microtrauma, such
as lack of exercise, poor nutrition, postural imbalances,
vitamin deficiencies, sleep disturbances and joint prob-
lems [7]. One study suggests overloading of muscle fibres
may lead to involuntary shortening, oxygen and vitamin
deficiencies and increased metabolic demand on local tis-
sues [8], and trigger points have been suggested as
decreasing the extensibility and contractile efficiency of
muscles, and possibly causing muscle fatigue [9]. This is
yet to be confirmed by research.
Trigger points have been shown to be active in fibromyal-
gia [10,11], as well as somatic tenderness secondary to vis-
ceral dysfunction [2], migraine and other forms of non-
pathological headache [12], shoulder [13] neck [14] and
back pain [15]. Specifically, Rosomoff and co-workers
[15] demonstrated that approximately 97% of persons
with chronic intractable pain have trigger points, and of
these, 45% have a non-dermatomal referred pain. Further-
more, Rosomoff's team demonstrated that 100% of neck
pain sufferers possessed the presence of trigger points and
almost 53% of them had non-dermatomal referral [15].
However, it is worthy of note that no evidence describes
the prevalence of trigger points of the neck and face in a
normal population. Indirect evidence presented in the
equine model suggests there to be significant differences
between active trigger points and control points [16].
The diagnosis of a trigger point involves physical exami-
nation by an experienced therapist using a set of cardinal
signs (Table 1) [1]. There have been many studies focused
on the assessment of the reliability of detecting trigger
points. Lew et al. [17] found that both inter and intra-rater
reliability, using two highly trained examiners was poor,
while Gerwin et al [18] found that extensive training of
four clinicians together resulted in improved reliability for
the identification of trigger points. Reeves et al. [19] dem-
onstrated a moderate degree of intra and inter examiner
reliability in determining the location of trigger points. In
older studies values ranged from r = 0.68 to r = 0.86 [19].
In a study by Delaney and McKee [20], interclass correla-
tion co-efficient (ICC) revealed inter-rater reliability to be
high (values ranged from ICC = 0.82 to ICC = 0.92), and
intra-rater reliabilities to be high (values ranged from ICC
= 0.80 to ICC = 0.91) for the use of a pressure threshold
meter in measuring trigger point sensitivity.
In both clinical and experimental practice, a device such
as the pressure algometer would be of great value for reli-
able quantification of trigger point sensitivities, once
manually located. Fischer [5] demonstrated that the use of
algometry in the detection of trigger points was a reliable
procedure. He assessed the pressure threshold of deep ten-
derness in soft tissues, before and after various forms of
treatment such as physiotherapy and drug therapy. In
addition, Reeves et al. [19] reviewed studies that demon-
strated the reliability of the pressure algometer. He found
Table 1: The Cardinal Signs of a Trigger Point (adapted from Simons, Travell and Simons [1]).
Cardinal Signs of a Trigger Point
- Presence of a taut band in the target muscle
- A nodular point of tenderness
- A jump sign: Patient reacts to the application of digital pressure to the taut band or nodular point
- Referral of pain on the application of pressure to the taut band or nodule
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that an experimenter was able to reliably obtain similar
measurements on two occasions, as well as produce simi-
lar scores to independent experimenters. He also noted
that agreement was found between two experimenters
when locating unmarked trigger points and measuring
their sensitivity, but did stress the importance that experi-
menters were experienced and trained. In patients who
present to manual therapists, the use of algometry can be
used to reliably quantify the tenderness associated with a
trigger point and can be used to diagnose their location as
well as to qualify the degree of pressure sensitivity.
Trigger points are potential outcomes of dysfunction in a
region, and conventional treatment is based around the
release of this taut band of skeletal muscle. Manual ther-
apy [21], chiropractic treatment [1,22], electric therapy
[23], local anaesthetic [24] and active therapy [25] have
all been claimed to provide relief of trigger point sensitiv-
ity. Injection therapies involved the use of local anaes-
thetic and saline, while it is postulated that massage and
myofascial release aim to increase local circulation,
improve mobility and relieve subcutaneous tightness. Fur-
thermore, the presence of trigger points has been fre-
quently associated with signs and symptoms in addition
to pain [26], and these syndromes may be in found in dis-
orders associated with chronic psychosocial factors [27].
Whilst it is likely the pathogenesis has at least a partly cen-
tral mechanism, most approaches to the management of
the trigger point phenomenon utilise only peripheral
approaches to the points themselves.
Therapy for trigger points requires an approach that
enhances the central inhibition through pharmacological
or behavioural techniques, and reduces the peripheral
inputs to the maintenance of the reflexes by utilising phys-
ical therapies such as exercise [28], needling and digital
pressure [29]. Offenbacher & Stucki [30] have also sug-
gested that a combined approach to therapy would be
warranted for patients exhibiting myofascial (as well as
other) symptoms in conditions such as fibromyalgia. It
was the specific aim of this research to investigate whether
a new mind body technique called Neuro Emotional
Technique (NET) could significantly relieve pain sensitiv-
ity of trigger points presenting in a cohort of neck pain suf-
ferers.
This study investigated the effects of Neuro Emotional
Technique (NET) on the sensitivity of trigger points pre-
senting in regions of the neck including the suboccipital
region, levator scapulae region, sternocleidomastoid
insertion region and temporomandibular region, in a
cohort of chronic neck pain sufferers. The results of the
study could provide useful information or the treatment
of cervical pain and related psychosocial problems.
Methods
This study received ethics approval from the Macquarie
University Ethics Committee, reference number:
HE24AUG2007-D05403.
Participants
This research was performed in a private practice setting in
Sydney, Australia. A convenience sample of sixty consecu-
tive participants was recruited from new patients present-
ing during the period between February 2005 and June
2005. Every third consecutive chronic neck pain partici-
pant was allocated to a blinded control group to eliminate
selection bias. This protocol resulted in 40 participants
allocated to the treatment group and 20 allocated to the
control group. Sequential allocation was concealed from
the participants. Participants provided informed written
consent prior to participating in the project.
All participants presenting with chronic cervical pain
(greater than 3 months duration) as their primary com-
plaint were invited to participate. Cervical pain was
defined as pain located from a horizontal line drawn at
the level of the 1
st
thoracic vertebrae to a horizontal line
drawn at the level nuchal line of the occiput, and laterally
to the lateral border of the trapezius muscles. Those par-
ticipants who did not have neck pain and headache, or
have acute cervical pain were excluded from the study, as
were participants under 18 years of age, or had undergone
recent surgery or were suffering any concurrent pathology.
Pre-Treatment Protocol
All participants underwent a standard patient evaluation
that included an interview, a questionnaire and a standard
physical examination. This provided information for each
participant in terms of age (years), sex, cause of injury (i.e.
motor vehicle accident), and duration of pain (months).
In addition, participants were evaluated for the presence
of cardinal signs of a trigger point (See Table 1) at four
specific areas. The four areas of trigger points specifically
targeted were the belly of the suboccipital (S) muscle,
levator scapulae (LS) insertion, sternocleidomastoid
(SCM) insertion and the belly of the masseter muscle
(referred to as the temporomandibular (TMJ) region)
(Figures 1, 2, 3).
The patients' perceived pain levels were assessed via a 100
mm visual analog scale (VAS) while the examiner pal-
pated and verified the existence of the trigger point. Partic-
ipants were asked to score the intensity of the pain using
a metal slider with a graduated 10-centimetre rule. Partic-
ipants were asked to rate their pain with zero (0) being no
pain and ten (10) being the worst pain they could imagine
by sliding the ruler to the point that represented their pain
on the scale 0 to 10. Gallagher reports a 13 mm difference
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on the VAS represents the smallest measurable change in
pain severity that is clinically important [31].
Furthermore, a pressure gauge algometer (PGA: Pain
Diagnostics & Thermography Inc, 17 Wooley Lane East,
Great Neck, NY 11021, USA) was used on the location of
the trigger point to assess the amount of pressure the
patient could sustain before the patient registered the
pressure as being painful. These assessments were per-
formed before and after the intervention. The pain thresh-
old meter or PGA consists of a rubber disc with a surface
of exactly 1 cm
2
that is attached to a force (pressure)
gauge. The gauge is calibrated in kilograms and pounds.
According to Smyth [32], the use of the device with a 1
cm
2
disc rather than other larger sizes at its tip has been
called more suitable for the assessment of deep muscle
trigger points.
The participants had the use of the PGA explained to them
using the protocol of Fischer [33], and also the location of
the pain. Following the explanation, the point of maxi-
mum tenderness was determined and marked with indel-
ible ink. Once marked, the pressure threshold was
determined using a control point in a non- painful muscle
in an unrelated area. The control point was taken as the
equivalent point on the opposite side of the body if not
tender; if tender another soft tissue non-tender point was
identified. Once determined, the practitioner guided the
tip of the gauge between the finger and the thumb to
avoid slipping by rounded contours. It was applied per-
pendicular to the long axis of the structure on which it was
placed (Figures 4, 5, 6, 7).
In addition, all participants were asked to rate the inten-
sity of the pain at the trigger point location on the appli-
cation of progressively increasing increments of pressure
(0.45 kg/2.54 cm2 (1 lb/inch 2) at 0.45 kg (1 lb) every one
second [34]). The practitioner used a PGA to score the
pain. The PGA measures the depth of depression of the
muscle during the application of pressure through the
device by the practitioner. Utilising this protocol, the
practitioner was able to determine the gross amount of
depression for a given pain score [34].
Sternocleidomastoid insertion trigger point regionFigure 3
Sternocleidomastoid insertion trigger point region.
Levator scapulae insertion trigger point regionFigure 2
Levator scapulae insertion trigger point region.
Suboccipital and temporomandibular trigger point regionFigure 1
Suboccipital and temporomandibular trigger point region.
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After participants were assessed for the cardinal signs of a
trigger point (Table 1) both groups received their assigned
intervention protocol. The control group received sham
NET protocol, whilst the treatment group received NET
protocol. Participants returned for re-assessment three
days post intervention (See Figure 8).
NET Treatment Protocol
After assessment, participants in the treatment group
underwent the NET protocol as outlined by Walker [35].
The detailed first 12 steps of the NET protocol used in this
study are shown in Additional File 1. Neuro Emotional
Technique, often described as a complementary and alter-
native medicine modality, was administered during the
study as a technique designed to incorporate central and
peripheral components to alleviate the effects of distress-
ing stimuli [36]. Developed by Walker [35], NET has been
described as a 15 step, multi-modal intervention that
incorporates principles of several health disciplines,
including cognitive behavioural psychology, traditional
Chinese medicine pulse assessment, and a feedback tech-
nique called the muscle test [37]. A major goal of NET is
to achieve a reversal (or extinction) of classically condi-
tioned distressing emotional responses to trauma related
stimuli, stimuli that have the characteristic ability to
reproduce or augment pain and other signs of disease
without the original stressor(s) being present. This objec-
tive is similar to treatments of standard cognitive behav-
ioural therapy for traumatic stress, such as exposure
therapy [36]. NET differs from such treatments in that it
supposedly engages the energy system as it is conceived in
the traditional Chinese medical model [38]. This entails
the patients touching the relevant pulse point on the wrist
that is determined to be involved in the body's stress reac-
tion to the given stimuli (Fig 9.) Using principles of tradi-
tional Chinese five-element theory [39], the therapist
helps the patient identify the particular pulse point using
an application of major energy channels, or 'meridians',
that contain specific emotional qualities. In the NET
framework it is thought that the engagement of the body's
energy system in the cognitive-emotional processing of an
event facilitates a resolution to the event [40]. NET aims
to help patients become less physiologically reactive to
distressing stimuli and to become more competent in
choosing alternative responses. NET is intended to be a
Suboccipital region pressure gauge algometer applicationFigure 4
Suboccipital region pressure gauge algometer application.
Levator scapulae insertion region pressure gauge algometer applicationFigure 5
Levator scapulae insertion region pressure gauge algometer
application.
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brief, time-limited intervention. Several recent publica-
tions have discussed the use of NET for conditions such as
hypothyroidism [41] and polycystic ovarian related infer-
tility [42]. In the only clinical trial, investigators demon-
strated a significant decrease in phobic symptoms
following a brief course (2–3 visits) of a variation of NET
[43,44].
Participants were asked to return 3 days later for assess-
ment of the pain level using the VAS and to determine the
status of the four cardinal signs of a trigger point using the
PGA.
Control Treatment Protocol
After the initial assessment, participants in the control
group underwent the sham NET protocol. This included
an information session, painless palpation of trigger
points and administration of a sham NET protocol. Partic-
ipants were asked to return 3 days later for assessment of
the pain level using the VAS and to determine the status of
the four cardinal signs of a trigger point using the PGA.
The assessments were performed by a chiropractor
(number one) and the treatment was provided by another
chiropractor (number two). The results of the study were
tabulated by a third chiropractor. Chiropractor number
one was unaware of the assignment of subjects to groups.
Statistical Analysis
The results were analysed using parametric statistics
because, within each treatment group, each of the
dependant variables exhibited uni-modal frequency dis-
tributions that did not differ significantly from normal
distributions. In all cases the threshold probability for sig-
nificance was 0.05.
Several different statistical methods were adopted. Data
analysis of group participation was performed using anal-
ysis of variance (ANOVA). The experimental design for
this project is split-plot, with patients allocated to treat-
ments and assessments made on each patient pre and post
treatment. As only two assessments were involved, the
split-plot analysis is equivalent to a Students t-test of dif-
ferences (pre-post for VAS scores and post-pre for PGA
measurements. We used GenStat (Payne et al, 2008) for
these analyses, with the package testing for treatment var-
iances automatically before testing for means.
Results
Participants
The average age for participants was 44.1 yrs old (S.D. =
11.7 yrs), with 56% female participants in the treatment
group and 55% in the control group. The average duration
of pain for all participants was 21.0 months (S.D. = 20.5
months). The severity of pain (an average of VAS scores
across trigger points) for patients arriving at the clinic was
8.8 (S.D. = 0.51). There were no significant differences
between the two groups for any of these variables (see
Table 2 for details).
Comparison of control and treatment groups
At all four trigger points, the average change in both VAS
scores and PGA measurements for the treatment group
was strongly significantly different (P < 0.001) from that
for the control group. The mean changes for the two
groups are presented in Table 3. In every case, there was
strong evidence (P < 0.001) of unequal sample variances,
and hence, for the t tests of equal means, variances were
Temporomandibular region pressure gauge algometer appli-cationFigure 7
Temporomandibular region pressure gauge algometer appli-
cation.
Sternocleidomastoid insertion region pressure gauge algom-eter applicationFigure 6
Sternocleidomastoid insertion region pressure gauge algom-
eter application.
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estimated separately for each group. (This form of the t
test is sometimes called the Satterthwaite t test.) Relative
changes to VAS and PGA have been shown in Figures 10
and 11. Scatter plots of raw data is presented for the reader
to visualise the variation between individuals for both the
VAS and PGA outcome measures (Fig 12 and 13).
Control group
For the control group, the change in mean VAS scores was
significantly different from 0 (P = 0.003) at the SCM trig-
ger point. However, the difference, 14 mm, was only just
clinically important; the 95% confidence interval (CI) for
this difference was (5 mm, 22 mm). None of the other
seven mean changes was significantly different from 0.
Treatment group
For the treatment group, all eight individual changes were
strongly significantly different from 0 (P < 0.001). The
mean change in VAS scale for S was 7.6 (95% CI: 7.3, 7.9),
LS was 7.2 (95% CI: 7.0, 7.4), SCM was 7.3 (95% CI: 6.5,
8.1) and TMJ was 6.9 (95% CI: 6.1, 7.7). The mean change
in PGA readings for S was 5.8 (95% CI: 5.6, 6.0), LS was
5.8 (95% CI: 5.7, 6.0), SCM was 5.9 (95% CI: 5.7, 6.1)
and TMJ was 5.8 (95% CI: 5.4, 6.3).
Correlation coefficients
Improvement at one particular trigger point was not asso-
ciated with similar improvements in the same subject for
any other measurement-trigger point combinations.
There were no significant pair-wise correlations amongst
the eight improvements (i.e., both VAS and PGA measure-
Trigger Point study – CONSORT FlowchartFigure 8
Trigger Point study – CONSORT Flowchart.
Trigger Point CONSORT Flowchart
Assessed for eligibility
(n= 60 participants)
Enrollment
Excluded (n= 0)
Randomisation
Allocated to NET protocol (n=40)
Received allocated intervention
(
n=40
)
Allocated to control (n=20)
Received allocated intervention
(
n=20
)
Lost to follow up (n=0)
Lost to follow up (n=0)
Analysed (n= 40) Analysed (n= 20)
Follow Up Period
– 3 days
Analysis
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ments and the four trigger points; P values > 0.05; Pearson
Correlation Test).
Discussion
Recordings of visual analog scale significantly decreased
in sensitivity, and pressure algometer readings signifi-
cantly increased after a single NET treatment. In this
cohort, the use of an NET based cognitive restructuring
and meridian correction protocol, which purports to iden-
tify an initial causative issue of the presenting pain and
dysfunction, had the ability to produce good improve-
ments in simple muscle pain outcomes in the short term,
in a small cohort of chronic neck pain sufferers. As a part
of the NET protocol psychosocial components of the
physical condition are considered. For example, emotion
and memory associated with any relevant traumatic event
is considered important in the recall of the painful experi-
ence, as investigated with the NET process. Participants
are encouraged to reflect with direct referential statements
on the variables whilst also considering the presenting
symptoms. The technique does not incorporate a "talk it
out therapy" or attempt to provide any psychoanalysis
during the process.
Pain is a complicated, individual and variable experience
[41]. Pain can alter in different conditions so it is impor-
tant to assess pain under standardised conditions. Pain
should be assessed: in the same location, on the same type
of tissue (muscle) in a similar area of sensitivity (neck has
a different sensitivity to a back or a knee), by the same
practitioner using the same method of assessment
[4,40,42]. Patient factors such as attitude, sex, cultural role
and age must be recognised in studies such as this, in
which participants record their own levels of pain [44].
Algometry is used to measure the sensitivity of pain or
pressure [4]. Algometer instrumentation can include man-
ual and electric models. The use of any experimental
instrument including the PGA must be tested for validity
and reliability between examiners and between perform-
ances of the same examiner. The PGA used in this study
has been tested against itself, palpation, pressure plates
with reliable results [17,18]. However, the above is based
on the assumption that the tester is trained in the applica-
tion of the PGA otherwise issues associated with the rate
of pressure application [45-47] the determination of an
end point based on a verbal patient response [45,46] and
the possible sensitisation of a selected landmark based on
repeated measures may all alter the accuracy of the out-
come.
This study used the PGA in near optimal conditions. Chi-
ropractor one, who used the PGA in the assessment of the
trigger points had been routinely using the PGA for several
years in a similar fashion to the use described in this study
and was thus highly trained in the operation of the PGA.
The electronic device, not used in this protocol, has been
described as being superior to non-electronic algometric
devices as such devices can control the rate of pressure
application and minimise examiner reaction as well as
calibrate itself [48]. The use of a highly trained individual
minimised the risk of error from these sources but did not
Table 2: Baseline comparisons of control and treated groups of patients
Control (n = 20) Treatment (n = 40)
Mean SEM
1
Mean SEM P for comparison
Age (years) 41.2 2.37 45.6 1.90 0.180
Time with pain (months) 19.5 3.59 21.7 3.57 0.700
Severity of trigger point pain on presentation (VAS) 8.9 0.08 8.8 0.09 0.374
SEM: Standard error of mean
Acupuncture pulse points used at the wristFigure 9
Acupuncture pulse points used at the wrist. From Walker
1996 [34] (Used with permission).
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eliminate it [49]. Despite early support, the ongoing utili-
sation of pressure algometry in manual therapy warrants
further research into the validity, effectiveness and best-
use principles of such an instrument.
This study represented a first small step into creating a
body of clinical literature on the usefulness of NET treat-
ment in chronic neck pain patients with trigger point
pain. The result of this study is encouraging for the man-
agement of trigger points and suggests psychosocial varia-
bles may have a beneficial effect on the intensity of trigger
points. This view is supported by the work of others [50-
53]. This contrasts with the usually described mechanisms
of trigger points that are more local or spinal in nature
[54,55]. However, if this research is reproducible it is still
unknown which component of NET is useful for painful
trigger points. It maybe that some, or all, components are
useful.
Limitations
No sample size was calculated prior to the commence-
ment of this research project. Whilst the validity and reli-
ability of NET treatments is far from proven, this study
establishes data that may be used in power calculations of
future studies to ensure that the sample sizes are large
enough to detect a worthwhile and statistically significant
effect.
No outcome measures were used to measure patient neck
pain, neck disability or global overall improvement as the
focus of this study was the resolution of the trigger points.
It is recommended that future studies specifically include
neck pain and a co variable and use appropriate outcome
measures such as the Neck Disability Index [56] or the
Patient-Specific Functional Scale [57]. In this trial we used
patient perceived pain levels and the amount of sustaina-
ble pressure via algometer readings at the trigger point site
to denote the level of activity of the trigger points. How-
ever, more extensive and clinically relevant outcome
measures will be required for use in the interpretation of
the effectiveness of this intervention in neck pain in the
clinical setting.
With regard to the ratio of treatment to control partici-
pants, the 2:1 ratio of allocation was chosen for two prag-
matic reasons. The first was to better estimate the effect of
Table 3: Changes to trigger point sensitivity in control and
treatment groups.
CONTROL (n = 20) TREATMENT (n = 40)
Mean SEM Mean SEM
VAS Subocc 0.02 0.05 7.6 0.16
Lev/Scap -0.03 0.06 7.2 0.11
SCM 0.14 0.04 7.6 0.24
TMJ 0.13 0.07 7.3 0.28
PGA Subocc 0.09 0.04 5.8 0.09
Lev/Scap 0.05 0.05 5.8 0.08
SCM 0.06 0.04 5.9 0.11
TMJ 0.08 0.05 5.8 0.23
VAS: visual analog scale; PGA: pressure gauge algometer readings;
Subocc: suboccipital trigger point location; Lev/Scap: levator scapulae
insertion trigger point location; SCM: sternocleidomastoid trigger
point location; TMJ: temporomandibular trigger point location)
Relative changes to visual analog scale scoresFigure 10
Relative changes to visual analog scale scores. (VAS: visual analog scale; PGA: pressure gauge algometer readings; Sub-
occ: suboccipital trigger point location; Lev/Scap: levator scapulae insertion trigger point location; SCM: sternocleidomastoid
trigger point location; TMJ: temporomandibular trigger point location).
Chiropractic & Osteopathy 2008, 16:4 http://www.chiroandosteo.com/content/16/1/4
Page 10 of 12
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this preliminary investigation on the target tissues. The
second and possibly more important factor, was the ethi-
cal requirement to provide patients who presented with
pain the best treatment possible, and not a sham/control
pseudo treatment. Future studies could incorporate a
"waiting list" approach [58] to treatment rendered to the
control group after allocation and completion of "treat-
ment" rendered in the sham/control group and after
appropriate informed consent.
This study was quasi-experimental; participants were
sequentially allocated into treatment and control groups.
Quasi-experiments are potentially prone to selection bias,
that is, unobservable effects that are either unknown to
the researcher or not easily measured which may ulti-
mately affect the study outcome. Randomised controlled
trials are the gold standard in evidence based research for
efficacy and causal relationship, whilst quasi-experimen-
tal studies provide evidence for clinical effectiveness and
Relative changes to pressure gauge algometer readingsFigure 11
Relative changes to pressure gauge algometer readings. (VAS: visual analog scale; PGA: pressure gauge algometer
readings; Subocc: suboccipital trigger point location; Lev/Scap: levator scapulae insertion trigger point location; SCM: sterno-
cleidomastoid trigger point location; TMJ: temporomandibular trigger point location).
Scatter plot of individual changes to visual analog scale scores in both the control and treatment groupsFigure 12
Scatter plot of individual changes to visual analog scale scores
in both the control and treatment groups.
Scatter plot of individual changes to pressure gauge algom-eter readings for both control and treatment groupsFigure 13
Scatter plot of individual changes to pressure gauge algom-
eter readings for both control and treatment groups.
Chiropractic & Osteopathy 2008, 16:4 http://www.chiroandosteo.com/content/16/1/4
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generalisability of results. In contrast to the evidence sup-
porting preferred use of RCT over quasi-experimental trial,
two recent meta-analyses presented evidence that non-
randomised trial data may not be inferior to that obtained
from RCTs [59,60]. They concluded that the value of the
trial rests largely on its real world validity, but this presup-
poses that the trial is till structurally sound as it would be
with an RCT.
Conclusion
Trigger points have been shown to be active in many myo-
fascial pain syndromes, and previous to this study, the
treatment of such trigger points supported the potential
use of central and peripheral approaches to relieve pain
and dysfunction associated with trigger points. Neuro
Emotional Technique was administered to provide partic-
ipants with a mind/body based treatment to relieve the
sensitivity of trigger points associated with their chronic
neck pain. It was found that after a short course of NET
treatment, visual analog scale and pressure algometer
measurements of four trigger point locations were signifi-
cantly reduced compared to pre-treatment. A sham NET
protocol did not produce significant changes in visual
analog scale or pressure algometer measurements. The
successful clinic based outcomes suggest that a mind body
approach to the management of trigger points with NET
should be considered in the management of trigger points
in neck pain sufferers. Further evidence is required for bet-
ter substantiation of the use in conservative management,
with randomised controlled trials for the effect of NET on
chronic neck pain, and other chronic pain syndromes rec-
ommended.
List of abbreviations
NET: Neuro Emotional Technique; ICC: Interclass correla-
tion co-efficient; S: Suboccipital; LS: Levator scapulae;
SCM: Sternocleidomastoid; TMJ: temporomandibular
region; VAS: Visual analog scale; PGA: Pressure gauge
algometer; CAM: complementary and alternative medi-
cine; ANOVA: Analysis of variance; SD: Standard devia-
tion; CI: Confidence Interval.
Competing interests
No funding was received in the preparation of this manu-
script.
PB: Is a research student of Macquarie University.
HP: is a part time employee of 'The ONE (Our Net Effect)
Research Foundation', a non-profit organisation. As an
employee of this organization his interest in this research
would relate to the foundation's mission statement: to
establish natural healing as a standardised care through
Neuro-Emotional Technique (NET) research, education
and public service.
RB: No competing interests.
Authors' contributions
* These authors contributed equally to this work
PB Conceived the idea of the study, wrote and edited the
manuscript
HP Conceived the idea of the study, wrote and edited the
manuscript.
RB Involved in data collection, reviewed and edited the
manuscript
All authors read and approved the final manuscript.
Additional material
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Click here for file
[http://www.biomedcentral.com/content/supplementary/1746-
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