title: Cerebellar theta burst stimulation does not improve freezing of gait in patients with Parkinson's disease.
abstract: Freezing of gait (FOG) in Parkinson's disease (PD) likely results from dysfunction within a complex neural gait circuitry involving multiple brain regions. Herein, cerebellar activity is increased in patients compared to healthy subjects. This cerebellar involvement has been proposed to be compensatory. We hypothesized that patients with FOG would have a reduced ability to recruit the cerebellum to compensate for dysfunction in other brain areas. In this study cerebellar activity was modified unilaterally by either excitatory or inhibitory theta burst stimulation (TBS), applied during two separate sessions. The ipsilateral cerebellar hemisphere, corresponding to the body side most affected by PD, was stimulated. Seventeen patients with PD showing 'off' state FOG participated. The presence of FOG was verified objectively upon inclusion. We monitored gait and bimanual rhythmic upper limb movements before and directly after TBS. Gait was evaluated with a FOG-provoking protocol, including rapid 360° turns and a 10-m walking test with small fast steps. Upper limb movement performance was evaluated with a repetitive finger flexion-extension task. TBS did not affect the amount of freezing during walking or finger tapping. However, TBS did increase gait speed when walking with small steps, and decreased gait speed when walking as fast as possible with a normal step size. The changes in gait speed were not accompanied by changes in corticospinal excitability of M1. Unilateral cerebellar TBS did not improve FOG. However, changes in gait speed were found which suggests a role of the cerebellum in PD.
authors.affiliation: Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands. Arno.Janssen@radboudumc.nl.|Department of Otorhinolaryngology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands. Arno.Janssen@radboudumc.nl.
authors.forename: Arno M
authors.identifier: http://orcid.org/0000-0002-5337-2962
authors.initials: AM
authors.lastname: Janssen
authors.affiliation: Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Moniek A M
authors.initials: MAM
authors.lastname: Munneke
authors.affiliation: Department of Rehabilitation, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Jorik
authors.initials: J
authors.lastname: Nonnekes
authors.affiliation: Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Thomas
authors.initials: T
authors.lastname: van der Kraan
authors.affiliation: Department of Rehabilitation Sciences, KU Leuven, Louvain, Belgium.
authors.forename: Alice
authors.initials: A
authors.lastname: Nieuwboer
authors.affiliation: Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands.
authors.forename: Ivan
authors.initials: I
authors.lastname: Toni
authors.affiliation: Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands.|Department of Neurology, Maasziekenhuis Pantein, Boxmeer, The Netherlands.
authors.forename: Anke H
authors.initials: AH
authors.lastname: Snijders
authors.affiliation: Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Bastiaan R
authors.initials: BR
authors.lastname: Bloem
authors.affiliation: Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Dick F
authors.initials: DF
authors.lastname: Stegeman
mesh_terms: D000328:Adult; D000368:Aged; D002531:Cerebellum / Q000502:physiology*; D004185:Disability Evaluation; D005260:Female; D020233:Gait Disorders, Neurologic / Q000209:etiology* / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications*; D011597:Psychomotor Performance / Q000502:physiology; D011712:Pyramidal Tracts / Q000503:physiopathology; D012720:Severity of Illness Index; D013826:Theta Rhythm; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D034941:Upper Extremity / Q000503:physiopathology
keywords: Cerebellum; Freezing of gait; Freezing of upper limbs; Parkinson’s disease; Theta burst stimulation