title: Intramuscular botulinum toxin A (BtxA) in complex regional pain syndrome.
abstract: BACKGROUND
  Pain associated with complex regional pain syndrome (CRPS) is frequently excruciating and intractable. The use of botulinum toxin for relief of CRPS-associated pain has not been well described.
  
  
  OBJECTIVE
  To assess whether intramuscular botulinum toxin injections cause relief of pain caused by CRPS, and to assess the risks of this treatment.
  
  
  METHODS
  Retrospective chart review.
  
  
  METHODS
  Outpatient clinic.
  
  
  METHODS
  
  
  
  METHODS
  37 patients with spasm/dystonia in the neck and/or upper limb girdle muscles.
  
  
  METHODS
  Electromyography-guided injection of botulinum toxin A (BtxA), 10-20 U per muscle. Total dose used was 100 U in each patient.
  
  
  METHODS
  Local pain score on an 11 point Likert scale, 4 weeks after BtxA injections.
  
  
  RESULTS
  Mean pain score decreased by 43% (8.2 ± 0.8 to 4.5 ± 1.1, P < 0.001). Ninety-seven percent of the patients had significant pain relief. One patient had transient neck drop after the injections.
  
  
  CONCLUSIONS
  This is a retrospective study; it lacks a control group and therefore the placebo effect cannot be eliminated. This study does not provide information on the efficacy of this treatment after 4 weeks.
  
  
  CONCLUSIONS
  Intramuscular injection of botulinum toxin A in the upper limb girdle muscles was beneficial for short term relief of pain caused by CRPS in this retrospective case series. The incidence of complications was low (2.7%).
authors.affiliation: Hahnemann University Hospital, Philadelphia, PA , USA.
authors.forename: Siddharth
authors.initials: S
authors.lastname: Kharkar
authors.forename: Prakash
authors.initials: P
authors.lastname: Ambady
authors.forename: Venkatesh
authors.initials: V
authors.lastname: Yedatore
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Schwartzman
mesh_terms: D019274:Botulinum Toxins, Type A / Q000008:administration & dosage*; D020918:Complex Regional Pain Syndromes / Q000188:drug therapy*; D020821:Dystonic Disorders / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007273:Injections, Intramuscular / Q000379:methods; D008297:Male; D009465:Neuromuscular Agents / Q000008:administration & dosage*; D012189:Retrospective Studies; D013035:Spasm / Q000188:drug therapy*
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A