OBJECTIVE: Motor evoked potential (MEP) amplitude and threshold are predictors of functional outcome in the early stages after stroke, and improvement in these parameters usually accompanies motor recovery. The aim of this study in patients with subcortical stroke was to determine whether there is a correlation between MEP amplitude and threshold and the degree of recovery of strength and dexterity in the affected hand. METHODS: MEP amplitude and threshold were measured on the affected and unaffected sides in 23 patients who had suffered a subcortical ischaemic stroke up to 23 years previously. Grip strength was measured using a hand-held dynamometer and dexterity was assessed using a modification of the McCarron test battery. RESULTS: Grip strength correlated with both MEP amplitude and threshold (r=0.49 and r=-0.54, respectively, P<0.05), whereas the McCarron score for motor dexterity did not correlate significantly with either of these MEP parameters. CONCLUSIONS: Grip strength and dexterity correlate differentially with MEP parameters of excitability and conduction in the corticospinal pathway after recovery in patients with subcortical stroke. Grip strength is dependent on restoration of corticospinal excitability and conduction whereas additional factors such as cortical reorganization may underlie recovery of motor dexterity.
OBJECTIVE: Motor evoked potential (MEP) amplitude and threshold are predictors of functional outcome in the early stages after stroke, and improvement in these parameters usually accompanies motor recovery. The aim of this study in patients with subcortical stroke was to determine whether there is a correlation between MEP amplitude and threshold and the degree of recovery of strength and dexterity in the affected hand. METHODS: MEP amplitude and threshold were measured on the affected and unaffected sides in 23 patients who had suffered a subcortical ischaemic stroke up to 23 years previously. Grip strength was measured using a hand-held dynamometer and dexterity was assessed using a modification of the McCarron test battery. RESULTS: Grip strength correlated with both MEP amplitude and threshold (r=0.49 and r=-0.54, respectively, P<0.05), whereas the McCarron score for motor dexterity did not correlate significantly with either of these MEP parameters. CONCLUSIONS: Grip strength and dexterity correlate differentially with MEP parameters of excitability and conduction in the corticospinal pathway after recovery in patients with subcortical stroke. Grip strength is dependent on restoration of corticospinal excitability and conduction whereas additional factors such as cortical reorganization may underlie recovery of motor dexterity.
Authors: Giovanni Di Pino; Giovanni Pellegrino; Giovanni Assenza; Fioravante Capone; Florinda Ferreri; Domenico Formica; Federico Ranieri; Mario Tombini; Ulf Ziemann; John C Rothwell; Vincenzo Di Lazzaro Journal: Nat Rev Neurol Date: 2014-09-09 Impact factor: 42.937
Authors: Eric T Wolbrecht; Justin B Rowe; Vicky Chan; Morgan L Ingemanson; Steven C Cramer; David J Reinkensmeyer Journal: Clin Neurophysiol Date: 2018-02-03 Impact factor: 3.708