title: Stimulated muscle force assessment of the sternocleidomastoid muscle in humans.
abstract: The aim of this study was to configure a force assessment device and determine potential testing protocols for quantitative evaluation of human neck muscles. The study design consisted of non-randomized control trials, with repeated measures; data from 12 normal subjects were obtained. Several apparatuses were designed, constructed and tested, i.e. single or short trains of supramaximal stimuli were used to activate sternocleidomastoid muscles in a seated position with strain gauges (6.2% variability with double-pulse stimulations) or in supine positions with load cells (5.2% variability with similar activation). Using a final configuration, maximum elicited peak forces were 1742 +/- 323 g for single-pulse and 3976 +/- 484 g for double-pulse stimulations (n = 12). There were no significant differences in maximum recorded peak torques between sessions per individual. Yet, detectable muscle activities were simultaneously recorded in the contralateral sternocleidomastoid muscles. This non-invasive, quantitative assessment approach has novel value for determining treatment efficacy, disease progression, and/or approach has novel value for determining determining treatment efficacy, disease progression, and/or relative distribution of muscle strength in patients with abnormal neck muscle function.
authors.affiliation: Department of Surgery, University of Minnesota, Minneapolis, MN 55455, USA.
authors.forename: J
authors.initials: J
authors.lastname: Hong
authors.forename: J H
authors.initials: JH
authors.lastname: Falkenberg
authors.forename: P A
authors.initials: PA
authors.lastname: Iaizzo
mesh_terms: D004558:Electric Stimulation / Q000295:instrumentation / Q000379:methods*; D004576:Electromyography; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D009334:Neck Muscles / Q000294:innervation* / Q000502:physiology*; D010808:Physical Examination / Q000295:instrumentation* / Q000379:methods*; D013314:Stress, Mechanical; D019415:Torque