iochemicals Associated With Pain and Inflammation are levated in Sites Near to and Remote From Active Myofascial rigger Points

Objectives: To investigate the biochemical milieu of the pper trapezius muscle in subjects with active, latent, or absent yofascial trigger points (MTPs) and to contrast this with that f the noninvolved gastrocnemius muscle. Design: We used a microanalytic technique, including neele insertions at standardized locations in subjects identified as ctive (having neck pain and MTP), latent (no neck pain but ith MTP), or normal (no neck pain, no MTP). We followed a redetermined sampling schedule; first in the trapezius muscle nd then in normal gastrocnemius muscle, to measure pH, radykinin, substance P, calcitonin gene-related peptide, tumor ecrosis factor alpha, interleukin 1 (IL-1 ), IL-6, IL-8, seroonin, and norepinephrine, using immunocapillary electrohoresis and capillary electrochromatography. Pressure algomtry was obtained. We compared analyte concentrations among roups with 2-way repeated-measures analysis of variance. Setting: A biomedical research facility. Participants: Nine healthy volunteer subjects. Interventions: Not applicable. Main Outcome Measures: Preselected analyte concentrations. Results: Within the trapezius muscle, concentrations for all anaytes were higher in active subjects than in latent or normal subjects P .002); pH was lower (P .03). At needle insertion, analyte conentrations in the trapezius for the active group were always higher pH not different) than concentrations in the gastrocnemius muscle. t all times within the gastrocnemius, the active group had higher oncentrations of all analytes than did subjects in the latent and ormal groups (P .05); pH was lower (P .01).