Hypoalgesic Effect of Electrical Current and Cervical Manipulation
Condition: Pain
Study type: Interventional

Summary: 
      This study evaluates the hypoalgesic effect of the TENS application associated with joint
      manipulation of the cervical region in healthy individuals. One group had both active
      treatments, the other group received both placebo treatments, the third and fourth group
      received only one of the two treatments actively and the other placebo
    

Detailed description: 
      Transcutaneous Electrical Nerve Stimulation (TENS) and Cervical Joint Manipulation (CJM) are
      often used for pain treatment.

      TENS also promotes analgesia by activating a descending pathway, which originates in the
      periaqueductal grey (PAG) and in the rostroventromedial medulla (RVM) to inhibit the
      excitability of nociceptive neurons in the dorsal horn of the spinal cord.

      Joint manipulation generates a series of stimuli within the central nervous system through
      the activation of proprioceptors located in the joint capsule or muscles, stimulates the PAG,
      causing pain inhibition by activation of non-opioid descending inhibitory pathways
    

Intervention name(s): Application of TENS; CJM; Placebo TENS; Placebo CJM
Intervention type(s): Device; Device; Device; Device
Intervention description(s): The subject's skin will be cleaned with mild soap and water. Two square self-adhesive electrodes (5x5cm) will be placed 1 cm below the olecranon of the ulna and 10 cm above the radiocarpal joint of the dominant hand, maintaining the PPT measurement region between two electrodes. Two identical TENS units will be used: an active and a placebo (Neurodyn Portable TENS, IBRAMED). The active unit will be applied with the patient in a supine position at a high frequency of 100 Hz, and pulse duration of 100 µs. Strong but comfortable intensity as dictated by each subject will be applied for 20 minutes. Participants will be asked about the intensity of TENS every 5 minutes, and if the intensity has faded, the intensity will be increased again to a strong but comfortable level.; The examiner 3, who is responsible for cervical joint manipulation, will enter the room and stand at the head of the patient. Using the middle phalanx of the second finger of one hand, the examiner will apply pressure laterally on the joint processes of C6 and C7 vertebrae; the examiner will cradle the patient's opposite side with the other hand and then perform an ipsilateral inclination towards the C6, C7 segments, followed by a contralateral rotation to the tissue barrier to perform a high-velocity low-amplitude manipulation (thrust). If the patient does not experience joint cavitation during the maneuver, two more attempts will be made. If no sound occurs on the third attempt, the joints will be considered manipulated.; The application of placebo TENS will be at a frequency of 100 Hz and pulse duration of 100 µs for 30 seconds. After the initial 30 seconds, the current amplitude will gradually decrease over 15 seconds until it reaches zero value. Participants will be informed that TENS can cause a slight tingling sensation or any sensation during the procedure. They will be asked every 5 minutes if they are comfortable, without increasing intensity as in the active TENS group; Placebo CJM will be performed using an identical position to the active manipulation, however, for only 15 seconds, as proposed by some authors that have used placebo group in their studies. The examiner shall not exert tension in the joint capsule of the segment to ensure the placebo effect. The maneuvers will be carried out by a physiotherapist with more than 5 years of experience in manual therapy. The active or placebo manipulation will be performed on the right or left side according to randomization.
Other intervention name(s): Transcutaneous Electrical Nerve Stimulation (TENS); Cervical Joint Manipulation; Placebo Transcutaneous Electrical Nerve Stimulation (TENS); Placebo Cervical Joint Manipulation
Allocation: Randomized
Intervention model: Factorial Assignment
Intervention model description: The participants will be randomly allocated into 4 groups: (G1) active TENS and CJM, (G2) placebo TENS and CJM, (G3) placebo TENS and active CJM, (G4) active TENS and placebo CJM.
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Basic Science
Keywords: TENS; cervical manipulation; pressure pain