Article

OBJECTIVE: To investigate the effects of antispastic drugs baclofen and
tizanidine on reflexes and volitional tasks. DESIGN: Double-blind,
placebo-controlled, crossover, before-after trial, pilot study. SETTING: Research
laboratory in a rehabilitation hospital. PARTICIPANTS: Men with chronic (>6mo)
motor incomplete spinal cord injury (N=10) were recruited for the study.
INTERVENTIONS: Tizanidine, baclofen, and placebo were tested in this study.
Agents were tested in separate experimental sessions separated by >1 week. MAIN
OUTCOME MEASURES: Reflex and strength were measured before and after the
administration of a single dose of each intervention agent. Electromyographic and
joint torque data were collected during assessments of plantar flexor stretch
reflexes, maximum contraction during motor-assisted isokinetic movements, and
maximum isometric knee extension and flexion. RESULTS: Reduced stretch reflex
activity was observed after the administration of either tizanidine or baclofen.
We observed that tizanidine had a stronger inhibitory effect on knee extensors
and plantar flexors whereas baclofen had a stronger inhibitory effect on the knee
flexors. The effects of these drugs on strength during isometric and isokinetic
tasks varied across participants, without a consistent reduction in torque output
despite decreased electromyographic activity. CONCLUSIONS: These results suggest
that antispastic drugs are effective in reducing stretch reflexes without
substantially reducing volitional torque. Differential effects of tizanidine and
baclofen on reflexes of flexors and extensors warrant further investigation into
patient-specific management of antispastic drugs.
CI - Copyright (c) 2014 American Congress of Rehabilitation Medicine. Published by
Elsevier Inc. All rights reserved.

Langue : ANGLAIS