David J Arpin1, Brenda L Davies1, Max J Kurz2. 1. Department of Physical Therapy, Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, NE, United States. 2. Department of Physical Therapy, Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, NE, United States. Electronic address: mkurz@unmc.edu.
Abstract
OBJECTIVE: To quantify the precision of the steady-state isometric control of the ankle plantarflexors musculature of individuals with multiple sclerosis (MS), and to evaluate if the precision is related to the mobility impairments. METHODS: Individuals with MS and healthy adults performed a submaximal steady-state isometric contraction with the ankle plantarflexors. The coefficient of variation was used to assess the amount of variability or error in the precision of the torques generated by the ankle plantarflexor musculature. The participants also walked across a digital mat at their preferred and fast-as-possible walking speeds, which recorded their spatiotemporal gait kinematics. RESULTS: The individuals with MS: (1) had reduced maximal voluntary torques at the ankle, (2) a greater amount of variability in the precision of the isometric ankle torques, (3) altered and more variable spatiotemporal gait kinematics, and (4) a greater amount of variability in the isometric ankle torques were related to a slower walking speed and cadence, shorter step length and a greater amount of gait variability. CONCLUSIONS: These results further fuels the impression that a reduction in control of the ankle joint musculature may be a key factor in the mobility and balance impairments seen in individuals with MS.
OBJECTIVE: To quantify the precision of the steady-state isometric control of the ankle plantarflexors musculature of individuals with multiple sclerosis (MS), and to evaluate if the precision is related to the mobility impairments. METHODS: Individuals with MS and healthy adults performed a submaximal steady-state isometric contraction with the ankle plantarflexors. The coefficient of variation was used to assess the amount of variability or error in the precision of the torques generated by the ankle plantarflexor musculature. The participants also walked across a digital mat at their preferred and fast-as-possible walking speeds, which recorded their spatiotemporal gait kinematics. RESULTS: The individuals with MS: (1) had reduced maximal voluntary torques at the ankle, (2) a greater amount of variability in the precision of the isometric ankle torques, (3) altered and more variable spatiotemporal gait kinematics, and (4) a greater amount of variability in the isometric ankle torques were related to a slower walking speed and cadence, shorter step length and a greater amount of gait variability. CONCLUSIONS: These results further fuels the impression that a reduction in control of the ankle joint musculature may be a key factor in the mobility and balance impairments seen in individuals with MS.
Authors: David J Arpin; Elizabeth Heinrichs-Graham; James E Gehringer; Rana Zabad; Tony W Wilson; Max J Kurz Journal: Hum Brain Mapp Date: 2017-05-09 Impact factor: 5.038
Authors: Awad M Almuklass; Leah Davis; Landon D Hamilton; Taian M Vieira; Alberto Botter; Roger M Enoka Journal: J Neurophysiol Date: 2018-01-03 Impact factor: 2.714
Authors: Chloe C Casagrande; Brandon J Lew; Brittany K Taylor; Mikki Schantell; Jennifer O'Neill; Pamela E May; Susan Swindells; Tony W Wilson Journal: Hum Brain Mapp Date: 2021-03-18 Impact factor: 5.038