The Electromyographic Activity of Thoracic Paraspinal Muscles Identified as Abnormal with Palpation

Abstract

We wish to amend results reported in our article on the electromyographic (EMG) activity of muscles underlying thoracic paraspinal sites detected as abnormal with palpation.1Fryer G Morris T Gibbons P Briggs A The electromyographic activity of thoracic paraspinal muscles identified as abnormal with palpation.J Manipulative Physiol Ther. 2006; 29: 437-447Google Scholar After further analysis of the EMG data files, it is now evident that the EMG recordings sampled where subjects were completely inactive (resting in the prone position) were affected by electromagnetic noise. Consequently, and contrary to our previous conclusion, these muscles were most likely inactive during resting conditions, which is consistent with the view of authorities in the field.2Basmajian JV New views on muscular tone and relaxation.Can Med Assoc J. 1957; 77: 203-205Google Scholar, 3Basmajian JV De Luca CJ Muscles alive: their function revealed by electromyography.5th ed. William & Wilkins, Baltimore1985Google ScholarWhen the data from these affected conditions (resting prone, press 1-3) were excluded from the split-pbt analysis of variance, a significant between-group effect was still evident (F2,31 = 4.65, P = .02), with a large between-group effect size (ηp2 = 0.23). ‘Reactivity’ of the nervous system to stimulation has been described as an important factor in muscle ‘tone’,3Basmajian JV De Luca CJ Muscles alive: their function revealed by electromyography.5th ed. William & Wilkins, Baltimore1985Google Scholar and it is possible that the muscles at these sites were inactive when relaxed, but abnormally reactive to stimuli, such as that produced from active and passive thoracic movement and, perhaps, palpation. Consistent with the conclusions in our article, deep muscles underlying these apparently abnormal sites appeared to have EMG characteristics that differed from adjacent regions, and further research is recommended. We wish to amend results reported in our article on the electromyographic (EMG) activity of muscles underlying thoracic paraspinal sites detected as abnormal with palpation.1Fryer G Morris T Gibbons P Briggs A The electromyographic activity of thoracic paraspinal muscles identified as abnormal with palpation.J Manipulative Physiol Ther. 2006; 29: 437-447Google Scholar After further analysis of the EMG data files, it is now evident that the EMG recordings sampled where subjects were completely inactive (resting in the prone position) were affected by electromagnetic noise. Consequently, and contrary to our previous conclusion, these muscles were most likely inactive during resting conditions, which is consistent with the view of authorities in the field.2Basmajian JV New views on muscular tone and relaxation.Can Med Assoc J. 1957; 77: 203-205Google Scholar, 3Basmajian JV De Luca CJ Muscles alive: their function revealed by electromyography.5th ed. William & Wilkins, Baltimore1985Google Scholar When the data from these affected conditions (resting prone, press 1-3) were excluded from the split-pbt analysis of variance, a significant between-group effect was still evident (F2,31 = 4.65, P = .02), with a large between-group effect size (ηp2 = 0.23). ‘Reactivity’ of the nervous system to stimulation has been described as an important factor in muscle ‘tone’,3Basmajian JV De Luca CJ Muscles alive: their function revealed by electromyography.5th ed. William & Wilkins, Baltimore1985Google Scholar and it is possible that the muscles at these sites were inactive when relaxed, but abnormally reactive to stimuli, such as that produced from active and passive thoracic movement and, perhaps, palpation. Consistent with the conclusions in our article, deep muscles underlying these apparently abnormal sites appeared to have EMG characteristics that differed from adjacent regions, and further research is recommended. The Electromyographic Activity of Thoracic Paraspinal Muscles Identified as Abnormal With PalpationJournal of Manipulative & Physiological TherapeuticsVol. 29Issue 6PreviewThe aim of this study was to compare the electromyographic (EMG) activity of deep muscles in the thoracic paravertebral gutter (PVG) detected as abnormal to palpation (AbPT) and reported as tender by the subject with muscles underlying nontender (NT), normal to palpation sites under various experimental conditions. Full-Text PDF ErratumJournal of Manipulative & Physiological TherapeuticsVol. 30Issue 8PreviewIn the July/August 2007 letter to the editor by Fryer et al, the author affiliations were incorrectly listed. The correct affiliations are below. Full-Text PDF