title: C2 Nerve Field Stimulation for the Treatment of Fibromyalgia: A Prospective, Double-blind, Randomized, Controlled Cross-over Study.
abstract: BACKGROUND
  Fibromyalgia is a condition characterized by widespread chronic pain. Due to the high prevalence and high costs, it has a substantial burden on society. Treatment results are diverse and only help a small subset of patients. C2 nerve field stimulation, aka occipital nerve stimulation, is helpful and a minimally invasive treatment for primary headache syndromes. Small C2 pilot studies seem to be beneficial in fibromyalgia.
  
  
  METHODS
  Forty patients were implanted with a subcutaneous electrode in the C2 dermatoma as part of a prospective, double-blind, randomized, controlled cross-over study followed by an open label follow up period of 6 months. The patients underwent 2 week periods of different doses of stimulation consisting of minimal (.1 mA), subthreshold, and suprathreshold (for paresthesias) in a randomized order. Twenty seven patients received a permanent implant and 25 completed the 6 month open label follow up period.
  
  
  RESULTS
  During the 6 week trial phase of the study, patients had an overall decrease of 36% on the fibromyalgia impact questionnaire (FIQ), a decrease of 33% fibromyalgia pain and improvement of 42% on the impact on daily life activities and quality. These results imply an overall improvement in the disease burden, maintained at 6 months follow up, as well as an improvement in life quality of 50%. Seventy six percent of patients were satisfied or very satisfied with their treatment. There seems to be a dose-response curve, with increasing amplitudes leading to better clinical outcomes.
  
  
  CONCLUSIONS
  Subcutaneous C2 nerve field stimulation seems to offer a safe and effective treatment option for selected medically intractable patients with fibromyalgia.
authors.affiliation: Department of Neurosurgery, University Hospital Antwerp, Belgium. Electronic address: mark.plazier@uza.be.
authors.forename: Mark
authors.initials: M
authors.lastname: Plazier
authors.affiliation: BRAI(2)N, Sint Augustinus Hospital Antwerp, Belgium.
authors.forename: Jan
authors.initials: J
authors.lastname: Ost
authors.affiliation: Department of Physical Health and Rehabilitation, University Hospital Antwerp, Belgium.
authors.forename: Gaëtane
authors.initials: G
authors.lastname: Stassijns
authors.affiliation: BRAI(2)N, Sint Augustinus Hospital Antwerp, Belgium; BRAI(2)N, Department of Surgical Sciences, Section of Neurosurgery, Dunedin School of Medicine, University of Otago, New Zealand.
authors.forename: Dirk
authors.initials: D
authors.lastname: De Ridder
authors.affiliation: School of Behavioral and Brain Sciences, The University of Texas at Dallas, USA.
authors.forename: Sven
authors.initials: S
authors.lastname: Vanneste
mesh_terms: D018592:Cross-Over Studies; D004311:Double-Blind Method; D004567:Electrodes, Implanted; D005356:Fibromyalgia / Q000628:therapy*; D006801:Humans; D017060:Patient Satisfaction; D010865:Pilot Projects; D011788:Quality of Life; D011795:Surveys and Questionnaires; D004561:Transcutaneous Electric Nerve Stimulation / Q000379:methods*; D016896:Treatment Outcome
keywords: C2 stimulation; Central sensitization; Fibromyalgia; Greater occipital nerve stimulation; Placebo-controlled