Abstract
M.Tech.
The aim of this single blinded clinical trial was to determine the most effective myofascial dry
needle insertion time for the relief of active trigger points in the trapezius muscle. It was
hypothesised that at least one of the three time frames chosen in this study; namely 30 seconds, 1.5
minutes and until the patients pain referral ceased, would prove to be the most effective time to
increase the patients pressure tolerance and decrease their subjective perception of pain.
Thirty six patients who presented with bilateral active trapezius trigger points and who fell into the
inclusion-exclusion criteria of this study were recruited from in and around the University of
Johannesburg. Once selected for the study the patients, whose ages ranged from 18 to 40 years of
age, where randomly divided into two groups of eighteen. In this study each patient served as their
own control. The left and right sides where randomly assigned to either being the control side
(needled for 30 seconds) or the experimental side (needled for 1.5 minutes or until the pain referral
stopped). Because of this further randomisation, the two groups of eighteen were divided in to four
groups of nine:
Group one: Right side was the control and the left side was needled for 1.5 minutes.
Group two: Right side was the control and the left side was needled until the patients pain referral
ceased.
Group three: Left side was the control and the right side was needled for 1.5 minutes.
Group four: left side was the control and the right side was needled until the patients pain referral
ceased.
The patients received a once off treatment, where they were needled bilaterally with the control side
being needled for 30 seconds and the experimental side being needled for either 1.5 minutes or until
the pain referral stopped. The patients were required to come back for a follow-up assessment two
days later.
Objective measurements were obtained by using the algometer, which measured the pressure
threshold of the left and right trapezius before the needling treatment, immediately after the
treatment and on the two day follow-up visit. Three reading were taken at each time interval.
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Subjective measurements were obtained by using the visual analogue scale (VAS) and a subjective
pain and discomfort questionnaire which patients were required to complete before the treatment,
immediately after the treatment and at the two day follow-up visit. The data was statistically
analysed using the Kruskal Wallis Test and the Wilcoxon Signed Ranks Test.
For the inter-group analysis for average algometer readings, due to the small sample size, only group
one and group four showed statistically significant changes in the average algometer readings over
time. In group one the control side showed the greatest change, and in group four both the control
and the experimental (which was needled until the pain referral ceased) showed a change in average
algometer readings. Although the statistical evidence is inconsistent, there was a general trend of
improvement seen over all four groups in terms of the average algometer readings over time.
Subjectively it was seen that all four groups had a statistical decrease in the patients perceived pain
with the VAS, with group four showing the most significant change over the three time variables
(pre to post, post to follow-up and pre to follow-up). Group one had a statistical change from the pre
reading to the post reading. Group two had a statistical change from the pre reading to the follow-up
reading. Group three had a statistical change from the pre reading to the post reading.
It was noted from the subjective pain and discomfort questionnaire that the patients who where
needled for 30 seconds experienced a persistent stiffness and pain (although less than what they
experienced before) immediately after the treatment and on their two day follow-up visit. This
contrasted with the patients who were needled for 1.5 minutes and until the pain referral ceased
(which averaged at 1 minute for group two and four) who experienced more relief immediately after
the treatment and on the two day follow-up visit.
From these results it is seen that even though objectively both the 30 second time frame and the
longer time frame proved to increase pressure threshold, subjectively the patients who were needled
for the longer time felt more relief than those who were needled for the shorter time frame.