Heat Transfer by Three Types of Packs and Its Implication on the Flexibility of the Lower Back
Condition: Physical Therapy Techniques
Study type: Interventional

Summary: 
      The purpose of this study is to compare the effects generated by the application of three
      different packs on the flexibility of the lower back of sedentary students. Method: Three
      sessions of 15 minutes of superficial heat through a hot pack (moist heat pack-MHP, seed
      pack-SP or gel pack-GP) were applied on the lower back. Pack and lower back temperatures and
      erythema were registered every 5 minutes. Schober test was performed before first session and
      after the third session.
    

Detailed description: 
      A different type of hot pack was applied in the lower back of each subject: moist heat pack
      (MHP) , seed pack (SP) or gel pack (GP) as directed by each manufacturer and in accordance
      with clinical practice for 15 minutes for 3 consecutive days. On day one, prior to the
      application of the pack, the initial evaluation of flexibility of the lumbar spine of each
      subject was recorded using Schober test. On day 3, after the application of each pack, the
      final evaluation of the flexibility of the lower back was performed using the same test.
      During the sessions, the temperature of the corporal area, the temperature of the pack and
      the pigmentation change of the corporal area were assessed every 5 minutes through a
      photographic record.The method used to assess the flexibility was the Schober Test. In order
      to perform the evaluation, the patient was placed in standing position with its bare feet
      slightly apart; two points were marked on the skin, one above the spinous apophysis S1 and
      another point, 10 cm above that mark. The patient performed a maximal trunk flexion without
      flexing the knees and the increase of the distance between the two marks was recorded. After
      this evaluation, the packs were applied on the lower back, wrapped in two layers of towels in
      order to avoid skin injuries by the heat. The temperature of the lower back and of each type
      of pack was recorded at minutes 0 (baseline measurement), 5, 10 and 15. Temperature was
      measured through a digital pyrometer at a set distance of 50 cm and it was held perpendicular
      to patient skin and the pack. The photographic record of the lower back of each subject,
      before and after each session of superficial thermotherapy, was recorded using a digital
      camera . The camera was placed perpendicular to the lower back, at a distance of 50 cm. The
      brightness of the photograph was taken into account so as not to affect the later analysis of
      the erythema. The erythema analysis of the lower back was performed with the freeware Picture
      Color Analyzer (Shizuoka, Japan; http://www.isao.com). The software measures the red color
      intensity of each pixel (attributing a value between 1 and 255) within the chosen area. The
      average red color value obtained in arbitrary units is the result of the following formula:
      Average red color = total red color value / (255 X number of pixels in the area).
    

Intervention name(s): moist heat pack; ;; seed pack; gel pack
Intervention type(s): Other; Other; Other
Intervention description(s): Three sessions of 15 minutes of superficial heat through a moist heat pack-MHP applied on the lower back.; Three sessions of 15 minutes of superficial heat through a seed pack-SP applied on the lower back.; Three sessions of 15 minutes of superficial heat through a gel pack-GP applied on the lower back.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Keywords: superficial heat; hot pack; thermotherapy; physiotherapy; Schober Test