title: Extracorporeal Shock Wave Therapy Accelerates Regeneration After Acute Skeletal Muscle Injury.
abstract: BACKGROUND
  Muscle injuries are among the most common sports-related lesions in athletes; however, optimal treatment remains obscure. Extracorporeal shock wave therapy (ESWT) may be a promising approach in this context, because it has gained increasing importance in tissue regeneration in various medical fields.
  
  
  OBJECTIVE
  ESWT stimulates and accelerates regenerative processes of acute muscle injuries.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  Adult Sprague-Dawley rats were divided into 4 experimental groups (2 ESWT+ groups and 2 ESWT- groups) as well as an uninjured control group (n ≥ 6 in each group). An acute cardiotoxin-induced injury was set into the quadriceps femoris muscle of rats in the experimental groups. A single ESWT session was administered to injured muscles of the ESWT+ groups 1 day after injury, whereas ESWT- groups received no further treatment. At 4 and 7 days after injury, 1 each of the ESWT+ and ESWT- groups was euthanized. Regenerating lesions were excised and analyzed by histomorphometry and immunohistochemistry to assess fiber size, myonuclear content, and recruitment of satellite cells.
  
  
  RESULTS
  The size and myonuclear content of regenerating fibers in ESWT+ muscle was significantly increased compared with ESWT- muscle fibers at both 4 and 7 days after injury. Similarly, at both time points, ESWT+ muscles exhibited significantly higher contents of pax7-positive satellite cells, mitotically active H3P+cells, and, of cells expressing the myogenic regulatory factors, myoD and myogenin, indicating enhanced proliferation and differentiation rates of satellite cells after ESWT. Mitotic activity at 4 days after injury was doubled in ESWT+ compared with ESWT- muscles.
  
  
  CONCLUSIONS
  ESWT stimulates regeneration of skeletal muscle tissue and accelerates repair processes.
  
  
  CONCLUSIONS
  We provide evidence for accelerated regeneration of damaged skeletal muscle after ESWT. Although further studies are necessary, our findings support the view that ESWT is an effective method to improve muscle healing, with special relevance to sports injuries.
authors.affiliation: Department of Cell Biology, University of Salzburg, Salzburg, Austria.
authors.forename: Angela
authors.initials: A
authors.lastname: Zissler
authors.affiliation: Department of Cell Biology, University of Salzburg, Salzburg, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Steinbacher
authors.affiliation: Department of Urology and Andrology, Salzburg General Hospital, Salzburg, Austria.
authors.forename: Reinhold
authors.initials: R
authors.lastname: Zimmermann
authors.affiliation: Department of Cell Biology, University of Salzburg, Salzburg, Austria.
authors.forename: Stefan
authors.initials: S
authors.lastname: Pittner
authors.affiliation: Department of Cell Biology, University of Salzburg, Salzburg, Austria.
authors.forename: Walter
authors.initials: W
authors.lastname: Stoiber
authors.affiliation: Department of Mathematics, University of Salzburg, Salzburg, Austria.
authors.forename: Arne C
authors.initials: AC
authors.lastname: Bathke
authors.affiliation: Department of Cell Biology, University of Salzburg, Salzburg, Austria.
authors.forename: Alexandra M
authors.initials: AM
authors.lastname: Sänger
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation / Q000502:physiology; D004195:Disease Models, Animal; D008096:Lithotripsy; D008297:Male; D008938:Mitosis / Q000502:physiology; D018485:Muscle Fibers, Skeletal / Q000502:physiology; D018482:Muscle, Skeletal / Q000293:injuries* / Q000502:physiology*; D017207:Rats, Sprague-Dawley; D012038:Regeneration / Q000502:physiology*; D032496:Satellite Cells, Skeletal Muscle / Q000502:physiology; D014945:Wound Healing / Q000502:physiology
keywords: healing enhancements; molecular biology; muscle regeneration