title: Temperature change in human muscle during and after pulsed short-wave diathermy.
abstract: METHODS
  A time series design was used, with the dependent variable being gastrocnemius muscle temperature at a depth of 3 cm.
  
  
  OBJECTIVE
  To determine the rate of temperature rise and the rate of post-treatment temperature decline in skeletal muscle following the application of pulsed short-wave diathermy (PSWD).
  
  
  BACKGROUND
  Data on PSWD rate and longevity of heating are 20 years old and outdated. With the recent introduction of advanced diathermy equipment, results of our study would provide clinicians with much needed information regarding treatment duration.
  
  
  METHODS
  A 23-gauge thermistor was inserted into the center of the medial head of the anesthetized gastrocnemius muscle, 3 cm below the skin's surface of 20 subjects. The PSWD (27.12 MHz frequency) was applied using the following parameters: 800 bursts per second; 400 microseconds burst duration; 850 microseconds interburst interval; with a peak root mean square (RMS) amplitude of 150 W per burst and an average RMS output of 48 W. Temperature changes were documented every 5 minutes during the treatment and additionally at 5 and 10 minutes following treatment.
  
  
  RESULTS
  The average baseline and peak temperatures were 35.84 +/- 0.93 degrees C and 39.80 +/- 0.83 degrees C, respectively. Mean temperature increases were: 1.36 +/- 0.90 degrees C (5 min); 2.87 +/- 1.44 degrees C (10 min); 3.78 +/- 1.19 degrees C (15 min); 3.49 +/- 1.13 degrees C (20 min). After the treatment terminated, intramuscular temperature dropped 0.97 +/- 0.68 degree C in 5 minutes and 1.78 +/- 0.69 degrees C in 10 minutes.
  
  
  CONCLUSIONS
  PSWD is an effective modality if temperature elevation of deep tissue over a large area is the clinical objective.
authors: Brigham Young University, Provo, Utah 84602, USA.
authors: D O
authors: DO
authors: Draper
authors: K
authors: K
authors: Knight
authors: T
authors: T
authors: Fujiwara
authors: J C
authors: JC
authors: Castel
mesh_terms: D000328:Adult; D001831:Body Temperature; D005260:Female; D006801:Humans; D007866:Leg / Q000502:physiology; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D012780:Short-Wave Therapy; D014464:Ultrasonic Therapy