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Surface mechanomyography and electromyography provide non-invasive indices of inspiratory muscle force and activation in healthy subjects.

ABSTRACT: The current gold standard assessment of human inspiratory muscle function involves using invasive measures of transdiaphragmatic pressure (P_di) or crural diaphragm electromyography (oesEMG_di). Mechanomyography is a non-invasive measure of muscle vibration associated with muscle contraction. Surface electromyogram and mechanomyogram, recorded transcutaneously using sensors placed over the lower intercostal spaces (sEMG_lic and sMMG_lic respectively), have been proposed to provide non-invasive indices of inspiratory muscle activation, but have not been directly compared to gold standard P_di and oesEMG_di measures during voluntary respiratory manoeuvres. To validate the non-invasive techniques, the relationships between P_di and sMMG_lic, and between oesEMG_di and sEMG_lic were measured simultaneously in 12 healthy subjects during an incremental inspiratory threshold loading protocol. Myographic signals were analysed using fixed sample entropy (fSampEn), which is less influenced by cardiac artefacts than conventional root mean square. Strong correlations were observed between: mean P_di and mean fSampEn |sMMG_lic| (left, 0.76; right, 0.81), the time-integrals of the P_di and fSampEn |sMMG_lic| (left, 0.78; right, 0.83), and mean fSampEn oesEMG_di and mean fSampEn sEMG_lic (left, 0.84; right, 0.83). These findings suggest that sMMG_lic and sEMG_lic could provide useful non-invasive alternatives to P_di and oesEMG_di for the assessment of inspiratory muscle function in health and disease.

SUBMITTER: Lozano-Garcia M

PROVIDER: S-EPMC6240075 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Surface mechanomyography and electromyography provide non-invasive indices of inspiratory muscle force and activation in healthy subjects.

Lozano-García Manuel M Sarlabous Leonardo L Moxham John J Rafferty Gerrard F GF Torres Abel A Jané Raimon R Jolley Caroline J CJ

Scientific reports 20181116 1

The current gold standard assessment of human inspiratory muscle function involves using invasive measures of transdiaphragmatic pressure (Pdi) or crural diaphragm electromyography (oesEMGdi). Mechanomyography is a non-invasive measure of muscle vibration associated with muscle contraction. Surface electromyogram and mechanomyogram, recorded transcutaneously using sensors placed over the lower intercostal spaces (sEMGlic and sMMGlic respectively), have ...[more]

PMID: 30446712

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Project description:BackgroundThere is currently no objective and accurate clinical assessment of reticular neuromuscular control in healthy subjects or patients with upper motor neuron injury. As a result, clinical dysfunctions of neuromuscular control could just be semi-quantified, efficacies and mechanisms of various therapies for neuromuscular control improving are difficult to verify.MethodsFourteen healthy participants were required to maintain standing balance in the kinetostatics model of Gusu Constraint Standing Training (GCST). A backward and upward constraint force was applied to their trunk at 0°, 20° and 25°, respectively. The multiplex recurrence network (MRN) was applied to analyze the surface electromyography signals of 16 muscles of bilateral lower limbs during the tests. Different levels of MRN network indices were utilized to assess reticular neuromuscular control.ResultsCompared with the 0° test, the MRN indices related to muscle coordination of bilateral lower limbs, of unilateral lower limb and of inter limbs showed significant increase when participants stood in 20° and 25° tests (P < 0.05). The indices related to muscle contribution of gluteal, anterior thigh and calf muscles significantly increased when participants stood in 20° and 25° tests (P < 0.05).ConclusionsThis study applied the dynamical network indices of MRN to analyze the changes of neuromuscular control of lower limbs of healthy participants in the kinetostatics model of GCST. Results showed that the overall coordination of lower limb muscles would be significantly enhanced during performing GCST, partly by the enhancement of neuromuscular control of single lower limb, and partly by the enhancement of joint control across lower limbs. In particular, the muscles in buttocks, anterior thighs and calves played a more important role in the overall coordination, and their involvement was significantly increased. The MRN could provide details of control at the bilateral lower limbs, unilateral lower limb, inter limbs, and single muscle levels, and has the potential to be a new tool for assessing the reticular neuromuscular control. Trial registration ChiCTR2100055090.

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Dataset Information

Surface mechanomyography and electromyography provide non-invasive indices of inspiratory muscle force and activation in healthy subjects.

Publications

Surface mechanomyography and electromyography provide non-invasive indices of inspiratory muscle force and activation in healthy subjects.

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