None listed
Conditions
Brief summary
The purpose of this study is to i) determine whether a 5-day block of high frequency rTMS, delivered to the motor cortex, can be used to treat the pain, mechanical hyperalgesia, and disability associated with repeated intramuscular injection of human nerve growth factor (NGF) and ii) determine whether a 5-day block of high frequency rTMS, delivered to the motor cortex, reduces the motor cortical changes associated with the transition from acute to sustained pain. Three injections of NGF will be delivered and active or sham rTMS will commence 4 days post-injection. prevent the transition from acute to sustained pain associated with repeated intramuscular injection of human nerve growth factor (NGF).
Interventions
This study involved 8 experimental sessions across a 14-day period (Day -2, 0, 2, 4, 6, 8, 11, and 14). Progressive muscle soreness and mechanical hyperalgesia are induced via repeated NGF injections. A 5 µg (0.2 mL) bolus of recombinant human NGF is injected into the muscle belly of the right ECRB using a 1 ml syringe and disposable 27G needle. Injections are administered at the end of the test sessions on Days 0, 2, and 4. The injection site is located 1cm lateral and 5cm distal to the origin
This study involved 8 experimental sessions across a 14-day period (Day -2, 0, 2, 4, 6, 8, 11, and 14). Progressive muscle soreness and mechanical hyperalgesia are induced via repeated NGF injections. A 5 µg (0.2 mL) bolus of recombinant human NGF is injected into the muscle belly of the right ECRB using a 1 ml syringe and disposable 27G needle. Injections are administered at the end of the test sessions on Days 0, 2, and 4. The injection site is located 1cm lateral and 5cm distal to the origin of a line extending from the lateral epicondyle to the midline of the wrist crease. One experimenter administers all injections. The intervention is high frequency repetitive transcranial magnetic stimulation (rTMS) applied to the motor cortex (the ‘hotspot’) region dedicated to the right ECRB using a Magstim Super Rapid2 (Magstim Co. Ltd, Dyfed, UK) and a 70mm air cooled figure-of-eight coil. A total of 1200 stimuli are delivered at a frequency of 10 Hz, in 20 trains of 6 seconds (54-second inter-train interval). Stimuli are delivered at 90% of the participant's resting motor threshold. Active or sham rTMS are delivered following repeated intramuscular injections. Each rTMS session takes approximately 20 minutes. The rTMS protocol consists of one session per day for 5 consecutive days (Days 4, 5, 6, 7, and 8), with rTMS being delivered after all assessments are performed. Stimuli are delivered by the chief investigator, who is familiar with the use of TMS. A second researcher is present to monitor the participant and the fidelity of the intervention. The chief investigator's supervisors provide support outside of the lab.
Sponsors
Western Sydney University
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject)
Eligibility
Sex/Gender
All
Age
20 Years to 50 Years
Healthy volunteers
Yes
Inclusion criteria
-Healthy -No previous exposure to repetitive transcranial magnetic stimulation (rTMS) - Able to understand and speak English
Exclusion criteria
-Failure to pass the Transcranial Magentic Stimulation Safety Screen questionnaire -Cardiovascular disorders -Use of neuroactive drugs -Pregnancy -History of neurological illness -History of musculoskeletal illness -Previous exposure to rTMS -Contraindications to rTMS or TMS -Current acute pain or recent musculoskeletal injury -History of chronic pain
Outcome results
None listed