title: Effects of transcutaneous electrical nerve stimulation and therapeutic exercise on quadriceps activation in people with tibiofemoral osteoarthritis.
abstract: METHODS
  Blinded, randomized controlled trial.
  
  
  OBJECTIVE
  To determine if the combination of transcutaneous electrical nerve stimulation (TENS) set to a sensory level and therapeutic exercise would be more effective than the combination of placebo TENS and therapeutic exercises or therapeutic exercises only to increase quadriceps activation in individuals with tibiofemoral osteoarthritis.
  
  
  BACKGROUND
  Quadriceps activation deficits are common in those with tibiofemoral osteoarthritis, and TENS has been reported to immediately increase quadriceps activation. Yet the long-term benefits of TENS for motor neuron activation have yet to be determined.
  
  
  METHODS
  Thirty-six individuals with radiographically assessed tibiofemoral osteoarthritis were randomly assigned to the TENS and exercise, placebo and exercise, and exercise only groups. All participants completed a supervised 4-week lower extremity exercise program. TENS and placebo TENS were worn throughout the therapeutic exercise sessions, as well as during daily activities. Our primary outcome measures, quadriceps central activation ratio, and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were evaluated at baseline and at 2 weeks and 4 weeks of the intervention.
  
  
  RESULTS
  Quadriceps activation was significantly higher in the TENS with exercise group compared to the exercise only group at 2 weeks (0.94 ± 0.04 versus 0.82 ± 0.12, P<.05) and the placebo and exercise group at 4 weeks (0.94 ± 0.06 versus 0.81 ± 0.15, P<.05). WOMAC scores improved in all 3 groups over time, with no significant differences among groups.
  
  
  CONCLUSIONS
  This study provides evidence that TENS applied in conjunction with therapeutic exercise and daily activities increases quadriceps activation in patients with tibiofemoral osteoarthritis and, while function improved for all participants, effects were greatest in the group treated with a combination of TENS and therapeutic exercises.
  
  
  METHODS
  Therapy, level 1b-.
authors.affiliation: Department of Kinesiology, University of Toledo, Toledo, OH, USA. brian.pietrosimone@utoledo.edu
authors.forename: Brian G
authors.initials: BG
authors.lastname: Pietrosimone
authors.forename: Susan A
authors.initials: SA
authors.lastname: Saliba
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Hart
authors.forename: Jay
authors.initials: J
authors.lastname: Hertel
authors.forename: D Casey
authors.initials: DC
authors.lastname: Kerrigan
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Ingersoll
mesh_terms: D000704:Analysis of Variance; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D007537:Isometric Contraction; D008297:Male; D020370:Osteoarthritis, Knee / Q000503:physiopathology / Q000534:rehabilitation*; D010919:Placebos; D052097:Quadriceps Muscle / Q000502:physiology*; D016037:Single-Blind Method; D004561:Transcutaneous Electric Nerve Stimulation; D016896:Treatment Outcome
chemical_list: D010919:Placebos