Effects of spinal cord stimulation on postural control in Parkinson's disease patients with freezing of gait
Abstract
Freezing of gait (FoG) in Parkinson's disease (PD) is an incapacitating transient phenomenon, followed by continuous postural disorders. Spinal cord stimulation (SCS) is a promising intervention for FoG in patients with PD, however its effects on distinct domains of postural control is not well known. The aim of this study is to assess the effects of SCS on FoG and distinct domains of postural control. Four patients with FoG were implanted with SCS systems in the upper thoracic spine. Anticipatory postural adjustment (APA), reactive postural responses, gait and FoG were biomechanically assessed. In general, the results showed that SCS improved FoG and APA. However, SCS failed to improve reactive postural responses. SCS seems to influence cortical motor circuits, involving the supplementary motor area. On the other hand, reactive posture control to external perturbation that mainly relies on neuronal circuitries involving the brainstem and spinal cord, is less influenced by SCS.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1 and 2.
Article and author information
Author details
Funding
Hospital das Clinicas, University of São Paulo Medical School
- Erich Talamoni Fonoff
Brazilian Council of Science and Technology
- Luis Augusto Teixeira
São Paulo Research Foundation
- Luis Augusto Teixeira
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: The study was approved by the department review board and in the ethics committee atHospital das Clinicas of University of São Paulo and registered in the national clinicalresearch database (CAPPESQ-HCFMUSP #12690213.0.0000.0068), which requires allparticipants to be previously instructed about the procedures and to give written informedconsent prior to study inclusion. Patients included in the present study participated in theclinical trial also registered in the clinicaltrials.gov (#NCT02388204). All experiments wereperformed in accordance with the Declaration of Helsinki
Reviewing Editor
- Amol Yadav, Duke University
Publication history
- Received: April 19, 2018
- Accepted: July 28, 2018
- Accepted Manuscript published: August 2, 2018 (version 1)
- Version of Record published: August 14, 2018 (version 2)
Copyright
© 2018, de Lima-Pardini et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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