title: Efficacy of botulinum toxin type a in the relief of Carpal tunnel syndrome: A preliminary experience.
abstract: OBJECTIVE
  Botulinum toxin type A has been shown to relieve primary headaches, myofascial pain and various neuropathic pains. Carpal tunnel syndrome (CTS) is a common disorder resulting from median nerve compression at the wrist. As reports of botulinum toxin A in the treatment of CTS were limited, this study set out to evaluate the safety and tolerability of botulinum toxin A and its effects on the relief of nerve entrapment and pain in patients with CTS.
  
  
  METHODS
  We conducted an open-label, prospective pilot study using 60 units of botulinum toxin A injected intracarpally in patients with primary CTS. Changes in median nerve conduction velocities, distal latencies, compound muscle action potentials and visual analogue scale (VAS) pain scores were evaluated for 3 months following injection. All adverse experiences, reported spontaneously or observed directly by the investigator, were recorded.
  
  
  RESULTS
  Five women aged 52.2 +/- 2.5 years with 1-2 years' history of CTS were enrolled. Botulinum toxin A was well tolerated and safe. No exacerbated hand weakness was observed in any of the patients. At 3 months, pain was lessened in three patients, remained static in one patient, and was aggravated in one patient. The VAS pain score showed a trend to improvement during the 3 months of follow-up, although it did not reach statistical significance (p = 0.2).
  
  
  CONCLUSIONS
  Our data suggest long-lasting antinociceptive effects of botulinum toxin A rather than electrophysiological restoration in patients with CTS. Intracarpal injection of botulinum toxin A was shown to be well tolerated and safe. A double-blind, placebo-controlled trial of botulinum toxin A in CTS is warranted since the current study may have been confounded by the placebo effect of intracarpal injection.
authors.affiliation: Department of Neurology, The Neurological Institute, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan. cptsai@vghtpe.gov.tw
authors.forename: Ching-Piao
authors.initials: CP
authors.lastname: Tsai
authors.forename: Chih-Yang
authors.initials: CY
authors.lastname: Liu
authors.forename: Kon-Ping
authors.initials: KP
authors.lastname: Lin
authors.forename: Kai-Chen
authors.initials: KC
authors.lastname: Wang
mesh_terms: D019274:Botulinum Toxins, Type A / Q000627:therapeutic use*; D002349:Carpal Tunnel Syndrome / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011446:Prospective Studies
chemical_list: D019274:Botulinum Toxins, Type A