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Effects of Manual vs Instrument-assisted Manipulation on Electromyographic Activity and Sympathetic Nervous System

Not Applicable
Completed
Conditions
Healthy
Interventions
Other: Placebo
Other: Manual Manipulation
Other: Instrument-assisted Manipulation
Registration Number
NCT03736148
Lead Sponsor
Escola Superior de Tecnologia da Saúde do Porto
Brief Summary

This study evaluates the effects of manual and instrument-assisted cervical manipulation on electromyographic activity and sympathetic nervous system. Subjects were divided in four groups, one group was submitted to a manual cervical manipulation, other group was submitted to an instrument-assisted cervical manipulation, other group was submitted to a sham manipulation and another group served as control.

Detailed Description

The manual manipulation was applied over C3/C4, as the participants were positioned in supine with the cervical spine in a neutral position. Slight ipsilateral side flexion and contralateral rotation were introduced until tension was perceived in the tissues at the contact point. A high-velocity, low-amplitude thrust manipulation was directed upward and medially in the direction of the subject's contralateral eye.

The instrument-assisted manipulation was applied using a handheld Activator IV Adjusting Instrument. Contacts were made firm enough to prevent slipping of the rubber tip but not so firm as to load the spring, in consistence with customary clinical use of the instrument. The spring was then loaded by means of the instrument's trigger mechanism, and the impulse was delivered in an anterosuperior direction, over the posterolateral aspect of the vertebra on the right lamina-pedicle junction of C3.

The sham manipulation to the right C3/C4 segment was administered using the same 'set-up' as for the manual manipulation; however, once the barrier was engaged, the head was re-positioned to neutral with no thrust applied. The control group individuals were positioned supine for the same twenty minutes as the other groups and they received no manual contact.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
75
Inclusion Criteria
  • Asymptomatic individuals
  • Age above 18 years.
Exclusion Criteria
  • Presence of cervical pain
  • History of surgery and/neck trauma
  • Osteoporosis
  • Current use of anticoagulant therapy
  • Presence of dizziness and/or vertigo
  • Pregnancy
  • Cancer
  • Any other contra-indication to spinal manipulation.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
PlaceboPlaceboA placebo manipulation was applied on C3/C4 level, on the right side. The neck of th subject was placed in the pre manipulative position but no thrust was made. Then, the cervical was replaced in neutral position.
Manual ManipulationManual ManipulationA single manual manipulation was applied to C3/C4 level, on the right side.
Instrument-assisted ManipulationInstrument-assisted ManipulationA single instrument-assisted manipulation was applied to C3/C4 level, on the right side.
Primary Outcome Measures
NameTimeMethod
Change of electromyographic activity of biceps brachii after spinal manipulation10 minutes post intervention

The effect on basal electromyographic activity of biceps brachii was compared between manual manipulation, instrument-assisted manipulation, placebo and control. Muscle activity was evaluated before and 10 minutes after each intervention.

Sympathetic Nervous System activity through change in skin conductance values10 minutes post intervention

The effect on sympathetic nervous system was compared between manual manipulation, instrument-assisted manipulation, placebo and control. The endodermic activity amplifier Galvanic Skin Response (GSR100C) was used to collect the skin conductance values.

Change of electromyographic activity of upper trapezius after spinal manipulation10 minutes post intervention

The effect on basal electromyographic activity of upper trapezius was compared between manual manipulation, instrument-assisted manipulation, placebo and control. Muscle activity was evaluated before and 10 minutes after each intervention.

Secondary Outcome Measures
NameTimeMethod
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