Byline: Shizuo Jimbo (1), Yuji Atsuta (2), Tetsuya Kobayashi (2), Takeo Matsuno (2)
Neck pain (katakori) is a common symptom in adult Japanese people.
However, the pathophysiological aspect of this condition has not been
well documented to date. The purpose of this study was to investigate
the effects of tender point dry needling to the trapezius muscles and
the resultant changes in muscular hemodynamics.
"Neck pain" patients were defined as those complaining of dull pain
or discomfort mainly along the trapezius muscles without serious spinal
or shoulder disorders. We used near-infrared spectroscopy to monitor
the changes of oxyhemoglobin (oxyHb) and deoxyhemoglobin (deoxyHb) of
the trapezius muscles and a Visual Analogue Scale (VAS) to assess
subjective neck pain intensity. Experiment I: Nine subjects with "neck
pain" and four control subjects were recruited. Total hemoglobin (Hb)
and SdO.sub.2 [= oxyHb/(oxyHb + deoxyHb)] were measured before and
immediately after needling for 15 min. We compared these parameters and
VAS before and immediately after needling. Experiment II: Thirteen
subjects with "neck pain" were instructed to perform isometric
contraction of their trapezius muscles for 1 min the half-recovery time
of SdO.sub.2 (defined as T .sub.R) was measured. After that, all
subjects underwent needling. On the next day, we repeated the
measurements of T .sub.R after the same voluntary contraction of the
trapezius muscle in the same patients. We compared T .sub.R and VAS
before and on the day after needling.
Experiment I: All subjects with "neck pain" reported significant
pain relief (P = 0.0147) measured by VAS immediately after needling,
but total Hb and SdO.sub.2 exhibited no significant change after
needling. Experiment II: T .sub.R was shortened on the day after
needling in 10 of 13 patients (P = 0.0043), and neck pain was decreased
in 12 patients (P = 0.0158).
After dry needling, total Hb and SdO.sub.2 did not change in real
time, but T .sub.R was shortened on the next day. These results showed
that the shortening of T .sub.R would provide a measure by which to
assess the effectiveness of treatment for neck pain.
(1) Department of Orthopaedic Surgery, Rishiri Island Central Hospital, Hokkaido, Japan
(2) Department of Orthopaedic Surgery, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
(3) Department of Orthopaedic Surgery, Engaru-Kosei General
Hospital, 3-1-5 Ohdori-kita, Engaru-cho, Monbetsu-gun, Hokkaido,