Bilateral coupling facilitates recovery of rhythmical movements from perturbation in healthy and post-stroke subjects

Effect of Object Texture and Weight on Ipsilateral Corticospinal Influences During Bimanual Holding in Humans

We tested the hypothesis that the ipsilateral corticospinal system, like the contralateral corticospinal system, controls the threshold muscle length at which wrist muscles and the stretch reflex begin to act during holding tasks. Transcranial magnetic stimulation was applied over the right primary motor cortex in 21 healthy subjects holding a smooth or coarse block between the hands. Regardless of the lifting force, motor evoked potentials in right wrist flexors were larger for the smooth block. This result was explained based on experimental evidence that motor actions are controlled by shifting spatial stretch reflex thresholds. Thus, the ipsilateral corticospinal system is involved in threshold position control by modulating facilitatory influences of hand skin afferents on motoneurons of wrist muscles during bimanual object manipulation.

Interlimb coupling in poststroke rehabilitation: a pilot randomized controlled trial

Background: The interlimb coupling, coordination between the limbs, gets hampered in post-stroke hemiparesis. Most of the poststroke motor regimes primarily focus on the more affected limb.Objectives: To develop an interlimb coupling protocol and assess its feasibility and effect on motor recovery, gait and disability among post-stroke subjects.Design: A pilot randomized controlled, doubled blinded trialSetting: A rehabilitation instituteMethods: 50 post-stroke (> 6 months) hemiparetic subjects (Brunnstrom recovery stage ≥ 3) were randomly divided into experimental (n=26) and control (n=24) groups. The 8-week experimental intervention (3 sessions of 1 hour each, per week) comprised activities demanding coordinated, alternate, and rhythmic use of the affected as well as the less-affected limbs. The outcome measures were feasibility of activities, Fugl-Meyer assessment (FMA), Rivermead visual gait assessment (RVGA), Functional ambulation category (FAC) and modified Rankin scale (mRS).Results: The experimental protocol was found to be feasible by the participants. Post intervention, the experimental group exhibited highly significant difference for FMA (mean difference = 7.12, 95% CI = 5.71 - 8.53, p < 0.001), RVGA reduction (mean difference = - 6.32, 95% CI = 7.51 - 5.13, p < 0.001), and median FAC enhancement (p < 0.001) in comparison to the controls. However, the median mRS level of experimental group did not change significantly (p = 0.056) when compared with the controls.Conclusions: The interlimb coupling training, a feasible program may enhance recovery of the upper and lower limbs and gait in stroke. Further definitive randomized trials are warranted to validate the present findings.

Correlation Between the Revised Brain Symmetry Index, an EEG Feature Index, and Short-term Prognosis in Acute Ischemic Stroke

PURPOSE

The present study aims to investigate the correlation between EEG features and short-term prognosis in patients who have experienced an acute ischemic stroke.

METHODS

The present study included 29 patients who had experienced an acute ischemic stroke and were treated at the Beijing Dongzhimen Hospital affiliated with Beijing University of Chinese Medicine between January 2010 and January 2012. Patients were evaluated using the revised Brain Symmetry Index (r-BSI), National Institutes of Health Stroke Scale, and Glasgow Coma Scale. Functional outcomes were assessed 21 days after admission using the Barthel Index and modified Rankin Scale. Two groups were created based on the Barthel Index (<60 vs. ≥60) and modified Rankin Scale (<3 vs. ≥3).

RESULTS

Significant differences were observed in r-BSI, National Institutes of Health Stroke Scale, and Glasgow Coma Scale scores between the two groups. Poor functional outcomes were associated with higher r-BSI and National Institutes of Health Stroke Scale scores as well as lower Glasgow Coma Scale scores in comparison with those obtained for patients with good prognosis. Logistic regression analysis revealed that r-BSI scores at admission exhibited significant negative correlation with Barthel Index scores (-2.070, P = 0.049) and significant positive correlation with modified Rankin Scale scores (2.256, P = 0.033).

CONCLUSIONS

The r-BSI may be a valuable prognostic tool in the prediction of short-term outcomes for patients who have experienced acute ischemic stroke.

SIGNIFICANCE

The early prediction of functional outcomes after stroke may enhance clinical management and minimize short-term mortality.

Efficacy and task structure of bimanual training post stroke: a systematic review

BACKGROUND

Bimanual training has been shown to be as effective as, but not superior to, unimanual paretic upper extremity (UE) training interventions in improving paretic UE function and use post stroke. However, it is still unclear whether different training interventions or task structures within bimanual interventions may differentially affect the outcomes.

OBJECTIVE

The objectives of this review were to (1) systematically determine the efficacy of bimanual training in relation to the International Classification of Functioning, Disability and Health model components and (2) explore the structure of current bimanual training interventions.

METHOD

A systematic review was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Eleven studies were accepted for review.

RESULTS

Three main types of bimanual training emerged: functional task training (FTT), bilateral training with rhythmic auditory cues (BATRAC), and robot-assisted training (RAT). Bimanual training is generally efficacious overall in improving paretic UE movement in individuals with subacute and/or chronic stroke as compared with other interventions. FTT, BATRAC, and RAT showed no significant differences compared with conventional therapy. Bimanual training may have greater proximal control benefits but fewer benefits in terms of subjects' perceived amount and quality of use as compared with constraint-induced movement therapy.

CONCLUSION

There were not enough data to draw any conclusions about the effects of bimanual task symmetry or commonality of goal.