title: Effect of Pulsed Wave Low-Level Laser Therapy on Tibial Complete Osteotomy Model of Fracture Healing With an Intramedullary Fixation.
abstract: BACKGROUND
  Fractures pose a major worldwide challenge to public health, causing tremendous disability for the society and families. According to recent studies, many in vivo and in vitro experiments have shown the positive effects of PW LLLT on osseous tissue.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the outcome of infrared pulsed wave low-level laser therapy (PW LLLT) on the fracture healing process in a complete tibial osteotomy in a rat model, which was stabilized by an intramedullary pin.
  
  
  METHODS
  This experimental study was conducted at Shahid Beheshti University of Medical Sciences in Tehran, Iran. We performed complete tibial osteotomies in the right tibias for the population of 15 female rats. The rats were divided randomly into three different groups: I) Control rats with untreated bone defects; II) Rats irradiated by a 0.972 J/cm(2) PW LLLT; and III) Rats irradiated by a 1.5 J/cm(2) PW LLLT. The right tibias were collected six weeks following the surgery and a three-point bending test was performed to gather results. Immediately after biomechanical examination, the fractured bones were prepared for histological examinations. Slides were examined using stereological method.
  
  
  RESULTS
  PW LLLT significantly caused an increase in maximum force (N) of biomechanical repair properties for osteotomized tibias in the first and second laser groups (30.0 ± 15.9 and 32.4 ± 13.8 respectively) compared to the control group (8.6 ± 4.5) LSD test, P = 0.019, P = 0.011 respectively). There was a significant increase in the osteoblast count of the first and second laser groups (0.53 ± 0.06, 0.41 ± 0.06 respectively) compared to control group (0.31 ± 0.04) (LSD test, P = 0001, P = 0.007 respectively).
  
  
  CONCLUSIONS
  This study confirmed the efficacy of PW LLLT on biomechanical strength, trabecular bone volume, callus volume, and osteoblast number of repairing callus in a complete tibial osteotomy animal model at a relatively late stage of the bone healing process.
authors.affiliation: Department of Anatomical Sciences and Biology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Atarodalsadat
authors.initials: A
authors.lastname: Mostafavinia
authors.affiliation: Department of Anatomical Sciences and Biology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Masteri Farahani
authors.affiliation: Department of Orthopedic Surgery, Akhtar Hospital, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Mohammadreza
authors.initials: M
authors.lastname: Abbasian
authors.affiliation: Paramedical School, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Mohammadmehdi
authors.initials: M
authors.lastname: Vasheghani Farahani
authors.affiliation: Department of Anatomy, Medical Faculty, Zanjan University of Medical Sciences, Zanjan, IR Iran.
authors.forename: Mohammadjavad
authors.initials: M
authors.lastname: Fridoni
authors.affiliation: Medical School, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Sara
authors.initials: S
authors.lastname: Zandpazandi
authors.affiliation: Department of Statistics, University of Qom, Qom, IR Iran.
authors.forename: Seyed Kamran
authors.initials: SK
authors.lastname: Ghoreishi
authors.affiliation: Department of Anatomical Sciences and Biology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Mohammad Amin
authors.initials: MA
authors.lastname: Abdollahifar
authors.affiliation: Medical School, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Ramin
authors.initials: R
authors.lastname: Pouriran
authors.affiliation: Department of Anatomical Sciences and Biology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Bayat
keywords: Biomechanical Phenomena; Histology; Low-Level Laser Therapy; Osteotomy; Rats; Tibial Fracture