Force assessment of the stimulated arm flexors: quantification of contractile properties

J Med Eng Technol. 2002 Jan-Feb;26(1):28-35. doi: 10.1080/03091900110099558.

Abstract

The primary objective was to develop equipment and evaluate protocols for non-invasive assessment of contractile properties of human arm flexors. The research design consisted of a non-randomized control trial, with repeated measures. Data from six males and two females were gathered in a clinical research laboratory. The elbow flexor torque following motor point or direct nerve stimulation was measured in response to single pulses or short trains of electrical pulses. Length--tension relationships were determined; comparative data were obtained at the identified optimal muscle lengths. Twitch waveforms and peak torques following either type of stimulation were reproducible (within 10%). Peak torques following a 4-pulse small interpulse interval stimulation were nearly identical for motor-point activation and direct nerve stimulation (15.2+/- 6.6Nm for motor point stimulation; 14.5 +/- 6.6Nm for nerve stimulation). Average perceived pain indexes associated with 4-pulse stimuli were slightly higher following nerve stimulation (782 for nerve versus 6.23 for motor-point, n=8). A reliable methodology (motor-point stimulation) has been identified to perform stimulated force assessment of human arm flexors.

MeSH terms

  • Adult
  • Biomechanical Phenomena
  • Elbow / innervation
  • Elbow / physiology*
  • Electric Stimulation / instrumentation
  • Electric Stimulation / methods*
  • Electrophysiology / instrumentation*
  • Electrophysiology / methods
  • Female
  • Humans
  • Male
  • Muscle Contraction / physiology
  • Muscle, Skeletal / innervation
  • Muscle, Skeletal / physiology*
  • Musculocutaneous Nerve / physiology*
  • Pain / physiopathology*
  • Pain Measurement / methods
  • Posture
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Torque