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Background: The efficacy of transcranial direct current stimulation (tDCS) has been studied extensively. The cathodic (c-tDCS), anodic (a-tDCS), and bihemispheric stimulation have demonstrated efficacy in the management of the paretic upper extremity (UE) after stroke, but it has not been determined which stimulation polarity has, so far, shown the best results., Objective: To evaluate the available evidence to determine which tDCS polarity has the best results in improving UE motor function after stroke., Methods: PubMed, PEDro, Web of Science, EMBASE, and SCOPUS databases were searched. Different Medical Subject Headings (MeSH) terms were combined for the search strategy, to cover all studies that performed a comparison between different tDCS configurations focused on UE motor rehabilitation in people with lived experience of stroke., Results: Fifteen studies remained for qualitative analysis and 12 for quantitative analysis. Non-significant differences with a 95% confidence interval (CI) were obtained for c-tDCS versus a-tDCS (g = 0.10, 95% CI = -0.13; 0.33, p = .39, N = 292), for a-tDCS versus bihemispheric (g = 0.02, 95% CI = -0.46; 0.42, p = .93, N = 81), and for c-tDCS versus bihemispheric (g = 0.09, 95% CI = -0.84; .66, p = .73, N = 100). No significant differences between the subgroups of the meta-analysis were found., Conclusions: The results of the present meta-analysis showed no evidence that a stimulation polarity is superior to the others in the rehabilitation of UE motor function after stroke. A non-significant improvement trend was observed toward c-tDCS compared to a-tDCS., (© 2023 American Academy of Physical Medicine and Rehabilitation.)

Background: Although there are studies that have examined brain functional reorganization following upper-limb amputation, understanding of the brain changes that occur in people with lower-limb amputation is limited., Objective: To investigate modifications in the brain following lower-limb amputation., Methods: We included case-control studies that evaluate neuroplasticity in the central nervous system using neuroimaging techniques. A literature search was conducted using MEDLINE, CINAHL, Web of Science, Scopus, and Cochrane., Results: Eleven articles were included (total n = 204 people with unilateral lower-limb amputation). These studies showed an increase in cerebellar gray matter volume in prosthesis users, as well as a decrease in thickness of the premotor cortex, orbitofrontal cortex, temporo-occipital junction, precentral gyrus, visual areas, and somatosensory cortex. Regarding white matter, the trials observed a decrease in the integrity at the corona radiata, the connections between the premotor areas, the fronto-occipital fasciculus and the corpus callosum. In addition, a decreased functional connectivity between cortical and subcortical areas has been described., Conclusions: Lower-limb amputation causes changes in several brain structures that may occur in the absence of pain and regardless of prosthesis use. The modifications observed include thinning or loss of gray matter volume, decrease in the integrity of the white matter connections between brain structures and changes in the functional connectivity between cortical and subcortical areas., Level of Evidence: I., (© 2019 American Academy of Physical Medicine and Rehabilitation.)

Background: Subjects with lower limb amputation develop new motor control strategies to preserve balance when they experience unexpected perturbations. Most studies performed thus far have not aimed to discuss the possible differences in postural control between subjects with vascular unilateral transtibial amputation (UTA) and subjects with traumatic UTA., Objective: To analyze the automatic postural reaction in response to unexpected surface perturbations in a sample of subjects with traumatic and vascular UTA and to compare these observations with those for a group of healthy subjects., Setting: University department., Design: Observational study., Participants: A total of 9 men with traumatic UTA, 7 men with vascular UTA, and 10 control subjects without amputation., Intervention: Computerized dynamic posturography Smart EquiTest System version 8.0 was used to measure automatic postural responses in both groups., Main Outcome Measures: The motor control test was used to assess the participants' automatic postural responses to unexpected surface perturbations., Results: Latency scores showed that subjects with traumatic UTA coped with faster latencies under their sound limb than did the subjects with vascular UTA in medium backward and forward perturbations (medium-backward: P = .004; medium-forward: P = .037). In addition, the subjects with traumatic UTA also managed faster responses to medium-backward (P = .017 versus right control limb; P = .046 versus left control limb) and large-backward (P = .021 versus right control limb) and medium-forward (P = .012 versus right control limb; P = .043 versus left control limb) perturbations in their sound limb in contrast to control subjects. Weight symmetry showed that the subjects with traumatic UTA bore significantly more weight through their sound limb compared with the control subjects during medium and large backward translations (P = .028 and P = .045, respectively)., Conclusions: The subjects with traumatic UTA had a greater reliance on their sound limb, and they had faster latencies and more weight in the sound limb upon experiencing unexpected perturbations compared with the control subjects. Conversely, persons with vascular UTA experienced slower latency responses in the sound limb compared with persons with traumatic UTA., (Copyright © 2016 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.)