title: Application of local anesthesia inhibits effects of low-energy extracorporeal shock wave treatment (ESWT) on nociceptors.
abstract: OBJECTIVE
  Clinical studies of extracorporeal shock wave therapy (ESWT) provided conflicting results depending on the use of local anesthesia (LA).
  
  
  METHODS
  The present study investigated whether the biological effects of ESWT differ between application with and without LA.
  
  
  METHODS
  In 20 healthy subjects, ESWT was applied to the ventral surface of forearm skin, either after topical lidocaine pretreatment or without on the corresponding contralateral side.
  
  
  METHODS
  During and after ESWT ongoing pain, axon-reflex vasodilation (laser Doppler imaging), thresholds for pinprick, and blunt pressure were recorded.
  
  
  RESULTS
  The results indicate that increasing ESWT energy flux density led to increasing pain (P < 0.001). LA reduced ESWT-related pain (P < 0.02) and in parallel inhibited local axon-reflex vasodilation (P < 0.001). In addition, LA prevented ESWT-related drop in pressure pain threshold (P < 0.001).
  
  
  CONCLUSIONS
  This study provided evidence that ESWT dose-dependently activates and sensitizes primary afferent nociceptive C-fibers, and that both activation and sensitization were prevented if LA was applied locally. These results suggest that LA substantially alters the biological responses of ESWT.
authors.affiliation: Department of Trauma Surgery, University Medical Centre, Mainz, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Klonschinski
authors.forename: S J
authors.initials: SJ
authors.lastname: Ament
authors.forename: T
authors.initials: T
authors.lastname: Schlereth
authors.forename: J D
authors.initials: JD
authors.lastname: Rompe
authors.forename: F
authors.initials: F
authors.lastname: Birklein
mesh_terms: D000293:Adolescent; D000328:Adult; D000772:Anesthesia, Local; D000779:Anesthetics, Local / Q000627:therapeutic use*; D060733:Electromagnetic Radiation; D005260:Female; D006801:Humans; D008297:Male; D036421:Nerve Fibers, Unmyelinated / Q000378:metabolism / Q000528:radiation effects; D009619:Nociceptors / Q000378:metabolism / Q000528:radiation effects*; D010146:Pain / Q000188:drug therapy* / Q000209:etiology*; D017288:Pain Threshold; D011897:Random Allocation; D055815:Young Adult
chemical_list: D000779:Anesthetics, Local