Biomechanical parameters of the elbow stretch reflex in chronic hemiparetic stroke. Exp Brain Res 2019 Jan;237(1):121-135
Date
10/26/2018Pubmed ID
30353212Pubmed Central ID
PMC6402810DOI
10.1007/s00221-018-5389-xScopus ID
2-s2.0-85055706853 (requires institutional sign-in at Scopus site) 14 CitationsAbstract
We sought to determine the relative velocity sensitivity of stretch reflex threshold angle and reflex stiffness during stretches of the paretic elbow joint in individuals with chronic hemiparetic stroke, and to provide guidelines to streamline spasticity assessments. We applied ramp-and-hold elbow extension perturbations ranging from 15 to 150°/s over the full range of motion in 13 individuals with hemiparesis. After accounting for the effects of passive mechanical resistance, we modeled velocity-dependent reflex threshold angle and torque-angle slope to determine their correlation with overall resistance to movement. Reflex stiffness exhibited substantially greater velocity sensitivity than threshold angle, accounting for ~ 74% (vs. ~ 15%) of the overall velocity-dependent increases in movement resistance. Reflex stiffness is a sensitive descriptor of the overall velocity-dependence of movement resistance in spasticity. Clinical spasticity assessments can be streamlined using torque-angle slope, a measure of reflex stiffness, as their primary outcome measure, particularly at stretch velocities greater than 100°/s.
Author List
McPherson JG, Stienen AHA, Schmit BD, Dewald JPAAuthor
Brian Schmit PhD Professor in the Biomedical Engineering department at Marquette UniversityMESH terms used to index this publication - Major topics in bold
AdultBiomechanical Phenomena
Chronic Disease
Elbow
Electromyography
Female
Humans
Male
Middle Aged
Movement
Paresis
Range of Motion, Articular
Reflex, Stretch
Stroke
Torque
