title: Efficacy of intrathecal baclofen on different pain qualities in complex regional pain syndrome.
abstract: BACKGROUND
  Complex regional pain syndrome (CRPS) is characterized by severe debilitating chronic pain. Patients with CRPS may experience various pain sensations, which likely embody different pathophysiologic mechanisms. In this study, we evaluated the differential effects of central γ-aminobutyric acid (B) receptor stimulation on the different pain qualities in CRPS patients with dystonia.
  
  
  METHODS
  The 10 pain qualities of the neuropathic pain scale, dystonia severity, and changes in use of antinociceptive drugs were evaluated every 3 months for a period of 1 year in 42 CRPS patients with dystonia receiving titrated doses of intrathecal baclofen (ITB) treatment in an open design.
  
  
  RESULTS
  Using a linear mixed model analysis and controlling for global dystonia severity and the use of supplemental analgesics, we found a significant improvement in global intense pain, sharp pain, dull pain, and deep pain during the first 6 months. After this period, the scores leveled off despite further improvement of dystonia and continued ITB dose escalation.
  
  
  CONCLUSIONS
  γ-Aminobutyric acid (B) receptor stimulation by ITB exerts differential antinociceptive effects on specific pain qualities in CRPS patients with dystonia.
authors.affiliation: Department of Neurology, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, the Netherlands. A.A.van_der_Plas@lumc.nl
authors.forename: Anton A
authors.initials: AA
authors.lastname: van der Plas
authors.forename: Monique A
authors.initials: MA
authors.lastname: van Rijn
authors.forename: Johan
authors.initials: J
authors.lastname: Marinus
authors.forename: Hein
authors.initials: H
authors.lastname: Putter
authors.forename: Jacobus J
authors.initials: JJ
authors.lastname: van Hilten
mesh_terms: D000328:Adult; D001418:Baclofen / Q000008:administration & dosage / Q000627:therapeutic use*; D020918:Complex Regional Pain Syndromes / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D004421:Dystonia / Q000150:complications; D005260:Female; D058785:GABA-A Receptor Agonists / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D007278:Injections, Spinal; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D009125:Muscle Relaxants, Central / Q000008:administration & dosage / Q000627:therapeutic use*; D010045:Outpatients; D059408:Pain Management / Q000379:methods; D010147:Pain Measurement / Q000187:drug effects; D016037:Single-Blind Method
chemical_list: D058785:GABA-A Receptor Agonists; D009125:Muscle Relaxants, Central; D001418:Baclofen