title: Long-term follow-up of chronic spinal cord stimulation for medically intractable orthostatic tremor.
abstract: Orthostatic tremor (OT) is a rare form of tremor occurring in the legs when standing upright. Medical treatment frequently is unsatisfactory, thus in selected cases, surgical treatment, such as spinal cord stimulation (SCS) or thalamic deep brain stimulation has been proposed. We report the long-term results (follow-up (FU) 34-133 months) of SCS in four patients with medically intractable OT. Outcome was assessed by recording the time tolerated to stand still pre- and post-operatively and by a patient self-rating (PSR) scale (0 = poor to 6 = excellent). Furthermore, surface electromyography (EMG) recordings of different leg muscles were performed to estimate tremor activity with and without SCS post-operatively. With chronic SCS, all four patients showed an improvement of unsteadiness occurring in the presence of stimulation-induced paraesthesia of the legs. The mean standing time improved from 51 s (SD 47 s, range 4-120 s) pre-operatively to 220 s (SD 184 s, range 10-480 s) with SCS at last available FU. Tremor activity in the EMG of the anterior tibial muscle was reduced by 30-60 % with SCS compared with off SCS. PSR score was 4 or 5 in three patients and 3 in the other. In conclusion, SCS is an effective long-term treatment option in patients with otherwise intractable OT.
authors: Department of Neurology, Universitaetsmedizin Mannheim, University of Heidelberg, Mannheim, Germany. c.blahak@neuro.ma.uni-heidelberg.de.
authors: Christian
authors: http://orcid.org/0000-0001-8426-7703
authors: C
authors: Blahak
authors: Department of Neurology, Universitaetsmedizin Mannheim, University of Heidelberg, Mannheim, Germany.
authors: Tamara
authors: T
authors: Sauer
authors: Department of Neurology, Universitaetsmedizin Mannheim, University of Heidelberg, Mannheim, Germany.
authors: Hansjoerg
authors: H
authors: Baezner
authors: Department of Neurology, Universitaetsmedizin Mannheim, University of Heidelberg, Mannheim, Germany.
authors: Marc E
authors: ME
authors: Wolf
authors: Department of Neurosurgery, Medical School Hannover MHH, Hannover, Germany.
authors: Assel
authors: A
authors: Saryyeva
authors: Department of Neurology, Medical School Hannover MHH, Hannover, Germany.
authors: Christoph
authors: C
authors: Schrader
authors: Department of Neurosurgery, Medical School Hannover MHH, Hannover, Germany.
authors: Hans-Holger
authors: HH
authors: Capelle
authors: Department of Neurology, Universitaetsmedizin Mannheim, University of Heidelberg, Mannheim, Germany.
authors: Michael G
authors: MG
authors: Hennerici
authors: Department of Neurosurgery, Medical School Hannover MHH, Hannover, Germany.
authors: Joachim K
authors: JK
authors: Krauss
mesh_terms: D000368:Aged; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000502:physiology; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D062187:Spinal Cord Stimulation / Q000379:methods*; D016896:Treatment Outcome; D014202:Tremor / Q000628:therapy*
keywords: Long-term follow-up; Orthostatic tremor; Spinal cord stimulation