Pain Relief
Conditions
Keywords
nerve growth factor, repetitive transcranial magnetic stimulation, dorsolateral prefrontal cortex
Brief summary
The main purpose of the study is to assess the mechanisms of repeated sessions of repetitive trancranial magnetic stimulation (rTMS) applied on left dorsolateral prefrontal cortex on the development of pain in a prolonged muscle pain model.
Detailed description
This study aims to investigate whether i) rTMS of left DLPFC will reduce the severity and duration of experimentally induced muscle pain when a 5-day course of treatment is given immediately following an initial nerve growth factor (NGF) injection; ii) the analgesic effects of left DLPFC rTMS will be related to an improved cognitive network function as assessed by electroencephalography (EEG).
Interventions
DEVICERepetitive trancranial magnetic stimulation (rTMS) group
Repetitive trancranial magnetic stimulation is applied on the dorsolateral prefrontal cortex. The protocol consists on 20 minutes of 10Hz stimulation, 5 seconds on, 10 seconds off, at 110% RMT, for a total of 4000 pulses.
DEVICESham group
A sham coil is used to mimic the clicking sound of the trancranial magnetic coil and skin stimulation.
Sponsors
Aalborg University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
21 Years to 50 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy men and women * Speak and understand English.
Exclusion criteria
* Pregnancy * Drug addiction defined as the use of cannabis, opioids or other drugs * Previous neurologic, musculoskeletal or mental illnesses * Lack of ability to cooperate * History of chronic pain or current acute pain * Previous experience with rTMS * Contraindications to rTMS application (history of epilepsy, metal in the head or jaw etc.). * Failure to pass the TASS questionnaire (TASS = Transcranial Magnetic Stimulation Adult Safety Screen)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Pain relief | Change from baseline at 2 weeks | Pain on an 11-point numerical rating scale (0 = no pain, 10 = most intense pain imaginable) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Patient-rated Tennis Elbow Evaluation | Change from baseline at 2 weeks | The Patient-rated Tennis Elbow Evaluation will be used to assess average pain and disability of the injected arm |
| Attention network test | Change from baseline at 2 weeks | This task assesses cognitive function in 3 domains: alerting, orienting, and executive function |
| Muscle soreness | Change from baseline at 2 weeks | 7-point Likert scale; 0 = 'a complete absence of soreness', 1 = 'a light soreness in the muscle felt only when touched/vague ache', 2 = 'a moderate soreness felt only when touched/a slight persistent ache', '3 = 'a light muscle soreness when lifting or carrying objects', 4 = 'a light muscle soreness, stiffness or weakness when moving the wrist without gripping an object', 5 = 'a moderate muscle soreness, stiffness or weakness when moving the wrist', 6 = 'a severe muscle soreness, stiffness or weakness that limits the ability to move' |
| Cuff pressure algometry | Change from baseline at 2 weeks | The experimental setup consists of a tourniquet cuff, a computer-controlled air compressor and an electronic visual analog scale VAS (Aalborg University, Denmark). The cuff is connected to the compressor and wrapped around the leg. The pain intensity is recorded with the electronic VAS and sampled at 10 Hz. The 0 cm and 10 cm extremes on the VAS are defined as no pain and as maximal pain, respectively. The compression rate of the cuff is programmed on and controlled by a computer. |
| EEG recordings | Change from baseline at 1 weeks | we will record brain activity in the following conditions: eyes closed rest, performance of a computer-based cognitive task (ANT). |
| Pressure pain thresholds | Change from baseline at 2 weeks | Pressure applied to the surface of the skin using a handheld algometer. |
Countries
Denmark
Outcome results
None listed