title: Focal hand dystonia: individualized intervention with repeated application of repetitive transcranial magnetic stimulation.
abstract: OBJECTIVE
  To examine for individual factors that may predict response to inhibitory repetitive transcranial magnetic stimulation (rTMS) in focal hand dystonia (FHD); to present the method for determining optimal stimulation to increase inhibition in a given patient; and to examine individual responses to prolonged intervention.
  
  
  METHODS
  Single-subject design to determine optimal parameters to increase inhibition for a given subject and to use the selected parameters once per week for 6 weeks, with 1-week follow-up, to determine response.
  
  
  METHODS
  Clinical research laboratory.
  
  
  METHODS
  A volunteer sample of subjects with FHD (N = 2). One participant had transcranial magnetic stimulation responses indicating impaired inhibition, and the other had responses within normative limits.
  
  
  METHODS
  There were 1200 pulses of 1-Hz rTMS delivered using 4 different stimulation sites/intensity combinations: primary motor cortex at 90% or 110% of resting motor threshold (RMT) and dorsal premotor cortex (PMd) at 90% or 110% of RMT. The parameters producing the greatest within-session increase in cortical silent period (CSP) duration were then used as the intervention.
  
  
  METHODS
  Response variables included handwriting pressure and velocity, subjective symptom rating, CSP, and short latency intracortical inhibition and facilitation.
  
  
  RESULTS
  The individual with baseline transcranial magnetic stimulation responses indicating impaired inhibition responded favorably to the repeated intervention, with reduced handwriting force, an increase in the CSP, and subjective report of moderate symptom improvement at 1-week follow-up. The individual with normative baseline responses failed to respond to the intervention. In both subjects, 90% of RMT to the PMd produced the greatest lengthening of the CSP and was used as the intervention.
  
  
  CONCLUSIONS
  An individualized understanding of neurophysiological measures can be an indicator of responsiveness to inhibitory rTMS in focal dystonia, with further work needed to determine likely responders versus nonresponders.
authors.affiliation: Program in Physical Therapy/Rehabilitation Science, Department of Physical Medicine and Rehabilitation, University of Minnesota, Minneapolis, MN. Electronic address: tjk@umn.edu.
authors.forename: Teresa Jacobson
authors.initials: TJ
authors.lastname: Kimberley
authors.affiliation: Program in Physical Therapy/Rehabilitation Science, Department of Physical Medicine and Rehabilitation, University of Minnesota, Minneapolis, MN.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Borich
authors.affiliation: Program in Physical Therapy/Rehabilitation Science, Department of Physical Medicine and Rehabilitation, University of Minnesota, Minneapolis, MN.
authors.forename: Rebekah L
authors.initials: RL
authors.lastname: Schmidt
authors.affiliation: Program in Physical Therapy/Rehabilitation Science, Department of Physical Medicine and Rehabilitation, University of Minnesota, Minneapolis, MN.
authors.forename: James R
authors.initials: JR
authors.lastname: Carey
authors.affiliation: Program in Physical Therapy/Rehabilitation Science, Department of Physical Medicine and Rehabilitation, University of Minnesota, Minneapolis, MN.
authors.forename: Bernadette
authors.initials: B
authors.lastname: Gillick
mesh_terms: D000328:Adult; D020821:Dystonic Disorders / Q000534:rehabilitation*; D019054:Evoked Potentials, Motor / Q000502:physiology; D005260:Female; D006225:Hand; D006236:Handwriting; D006801:Humans; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000503:physiopathology; D026741:Physical Therapy Modalities; D050781:Transcranial Magnetic Stimulation / Q000379:methods*
keywords: Clinical; Dystonia; Focal dystonia; Rehabilitation; Transcranial magnetic stimulation