title: Spared Primary Motor Cortex and The Presence of MEP in Cerebral Palsy Dictate the Responsiveness to tDCS during Gait Training.
abstract: The current priority of investigations involving transcranial direct current stimulation (tDCS) and neurorehabilitation is to identify biomarkers associated with the positive results of the interventions such that respondent and non-respondent patients can be identified in the early phases of treatment. The aims were to determine whether: (1) present motor evoked potential (MEP); and (2) injuries involving the primary motor cortex, are associated with tDCS-enhancement in functional outcome following gait training in children with cerebral palsy (CP). We reviewed the data from our parallel, randomized, sham-controlled, double-blind studies. Fifty-six children with spastic CP received gait training (either treadmill training or virtual reality training) and tDCS (active or sham). Univariate and multivariate logistic regression analyses were employed to identify clinical, neurophysiologic and neuroanatomic predictors associated with the responsiveness to treatment with tDCS. MEP presence during the initial evaluation and the subcortical injury were associated with positive effects in the functional results. The logistic regression revealed that present MEP was a significant predictor for the six-minute walk test (6MWT; p = 0.003) and gait speed (p = 0.028), whereas the subcortical injury was a significant predictor of gait kinematics (p = 0.013) and gross motor function (p = 0.021). In this preliminary study involving children with CP, two important prediction factors of good responses to anodal tDCS combined with gait training were identified. Apparently, MEP (integrity of the corticospinal tract) and subcortical location of the brain injury exerted different influences on aspects related to gait, such as velocity and kinematics.
authors.affiliation: Center of Pediatric Neurosurgery, CENEPE-RehabilitationSão Paulo, Brazil; Movement Analysis Laboratory, Department of Rehabilitation Sciences, University Nove de JulhoSão Paulo, Brazil.
authors.forename: Luanda A Collange
authors.initials: LA
authors.lastname: Grecco
authors.affiliation: Movement Analysis Laboratory, Department of Rehabilitation Sciences, University Nove de Julho São Paulo, Brazil.
authors.forename: Claudia Santos
authors.initials: CS
authors.lastname: Oliveira
authors.affiliation: Department of Electronics, Computer Science and Bioengineering (DEIB), Politecnico di MilanoMilano, Italy; IRCCS San Raffaele PisanaRome, Italy.
authors.forename: Manuela
authors.initials: M
authors.lastname: Galli
authors.affiliation: PostGraduate Program-Interactive Process of Organs and Systems, Health Sciences Institute, Federal University of Bahia Salvador, Brazil.
authors.forename: Camila
authors.initials: C
authors.lastname: Cosmo
authors.affiliation: Movement Analysis Laboratory, Department of Rehabilitation Sciences, University Nove de Julho São Paulo, Brazil.
authors.forename: Natália de Almeida Carvalho
authors.initials: Nde A
authors.lastname: Duarte
authors.affiliation: Center of Pediatric Neurosurgery, CENEPE-Rehabilitation São Paulo, Brazil.
authors.forename: Nelci
authors.initials: N
authors.lastname: Zanon
authors.affiliation: Departments of Neurology and Neuroscience, Burke Medical Research Institute, Weill Medical College of Cornel University White Plains, NY, USA.
authors.forename: Dylan J
authors.initials: DJ
authors.lastname: Edwards
authors.affiliation: Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital, Massachusetts General Hospital, Harvard Medical School Boston, MA, USA.
authors.forename: Felipe
authors.initials: F
authors.lastname: Fregni
keywords: cerebral palsy; gait training; motor evoked potential; neuromodulation; non-invasive brain stimulation