title: Effects of Therapeutic Physical Agents on Achilles Tendon Microcirculation.
abstract: METHODS
  Controlled laboratory study.
  
  
  OBJECTIVE
  To measure Achilles tendon microcirculation (total hemoglobin [THb] and oxygen saturation [StO2]) before and after the application of a physical agent in asymptomatic participants, and to compare differences between application location and physical agent dosage.
  
  
  BACKGROUND
  Tendon microcirculation can be altered by superficial heating or cryotherapy.
  
  
  METHODS
  Fifty-one healthy adults (median age, 22 years; range, 20-34 years) were recruited and randomly assigned into 1 of 4 groups. Participants in each group received an intervention consisting of 1 of the following 4 physical agents: ultrasound (n = 12), interferential current (n = 14), low-level laser (n = 11), or vibration massage (n = 14). In each group, the selected intervention was applied at 2 different doses (ultrasound, 0.8 or 1.2 W/cm(2); laser, 5.4 or 18 J) or target locations (vibration and electrostimulation, calf muscle or Achilles tendon). For each participant, each dose or target location was randomly applied to 1 randomly selected lower leg (each leg receiving only 1 of the 2 options).
  
  
  RESULTS
  The StO2 values significantly increased after ultrasound at both doses (P<.008), and the THb value significantly increased for the higher dose only (P<.008). Both THb and StO2 values also significantly increased in response to vibration massage targeting the Achilles tendon (P<.008), and these values were greater than those resulting from the vibration massage applied to the calf muscle (P = .003 and .002, respectively). No significant THb and StO2 differences were found after the application of interferential current or low-level laser.
  
  
  CONCLUSIONS
  Tendon microcirculation increases after ultrasound and vibration massage intervention concentrated on the Achilles tendon. These modalities may be considered for the purpose of temporarily increasing microcirculation in the tendon.
authors.affiliation: School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University, Taipei, Taiwan.
authors.forename: Yi-Ping
authors.initials: YP
authors.lastname: Chang
authors.forename: Hongsen
authors.initials: H
authors.lastname: Chiang
authors.forename: Kao-Shang
authors.initials: KS
authors.lastname: Shih
authors.forename: Hsiao-Li
authors.initials: HL
authors.lastname: Ma
authors.forename: Leou-Chyr
authors.initials: LC
authors.lastname: Lin
authors.forename: Wei-Li
authors.initials: WL
authors.lastname: Hsu
authors.forename: Yung-Cheng
authors.initials: YC
authors.lastname: Huang
authors.forename: Hsing-Kuo
authors.initials: HK
authors.lastname: Wang
mesh_terms: D000125:Achilles Tendon / Q000098:blood supply*; D000328:Adult; D004599:Electric Stimulation Therapy; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D028022:Low-Level Light Therapy; D008297:Male; D008833:Microcirculation / Q000528:radiation effects*; D011897:Random Allocation; D014464:Ultrasonic Therapy; D014732:Vibration; D055815:Young Adult
keywords: interferential current; laser; ultrasound; vibration