title: The effects of low-intensity pulsed ultrasound on tendon-bone healing in a transosseous-equivalent sheep rotator cuff model.
abstract: OBJECTIVE
  The purpose of this study was to examine the effects Low-intensity Pulsed Ultrasound has on initial tendon-bone healing in a clinically relevant extra-articular transosseous-equivalent ovine rotator cuff model.
  
  
  METHODS
  Eight skeletally mature wethers, randomly allocated to either control group (n = 4) or treatment group (n = 4), underwent rotator cuff surgery following injury to the infraspinatus tendon. All animals were killed 28 days post surgery to allow examination of early effects of Low-intensity Pulsed Ultrasound treatment.
  
  
  RESULTS
  General improvement in histological appearance of tendon-bone integration was noted in the treatment group. Newly formed woven bone with increased osteoblast activity along the bone surface was evident. A continuum was observed between the tendon and bone in an interdigitated fashion with Sharpey's fibres noted in the treatment group. Low-intensity Pulsed Ultrasound treatment also increased bone mineral density at the tendon-bone interface (p < 0.01), while immunohistochemistry results revealed an increase in the protein expression patterns of VEGF (p = 0.038), RUNX2 (p = 0.02) and Smad4 (p = 0.05).
  
  
  CONCLUSIONS
  The results of this study indicate that Low-intensity Pulsed Ultrasound may aid in the initial phase of tendon-bone healing process in patients who have undergone rotator cuff repair. This treatment may also be beneficial following other types of reconstructive surgeries involving the tendon-bone interface.
authors.affiliation: Surgical and Orthopaedic Research Laboratories, Prince of Wales Clinical School, University of New South Wales, Sydney, NSW, 2031, Australia.
authors.forename: Vedran
authors.initials: V
authors.lastname: Lovric
authors.forename: Michael
authors.initials: M
authors.lastname: Ledger
authors.forename: Jerome
authors.initials: J
authors.lastname: Goldberg
authors.forename: Wade
authors.initials: W
authors.lastname: Harper
authors.forename: Nicky
authors.initials: N
authors.lastname: Bertollo
authors.forename: Matthew H
authors.initials: MH
authors.lastname: Pelletier
authors.forename: Rema A
authors.initials: RA
authors.lastname: Oliver
authors.forename: Yan
authors.initials: Y
authors.lastname: Yu
authors.forename: William R
authors.initials: WR
authors.lastname: Walsh
mesh_terms: D000818:Animals; D015519:Bone Density; D001842:Bone and Bones / Q000528:radiation effects*; D004195:Disease Models, Animal; D008297:Male; D017006:Rotator Cuff / Q000528:radiation effects / Q000601:surgery*; D000070636:Rotator Cuff Injuries; D012756:Sheep; D013710:Tendons / Q000528:radiation effects*; D014464:Ultrasonic Therapy; D014945:Wound Healing / Q000528:radiation effects*