Healthy Subjects, Hyperalgesia, Pain Response
Conditions
Keywords
NGF-induced hyperalgesia, Exercise-induced ischemic pain, Pain modulation, NGF pain model
Brief summary
The purpose of this study is to investigate responses of pain and the maintenance of mechanical muscle hypersensitivity following an acute exercise-induced ischemic condition repeated over time in a prolonged NGF-sensitized muscle. Additionally, the influence of the pain modulating system on prolonged NGF muscle hypersensitivity caused by peripheral mechanisms and central mechanisms will also be investigated.
Detailed description
The hypothesis is that an ischemic conditioning in a NGF-sensitized muscle is able to facilitate pain responses and that over time the pain modulation system is responsible for a subsequent reduction in muscle sensitivity towards mechanical pressure and a decrease in pain intensity following a period of NGF-induced muscle hypersensitivity.
Interventions
DRUGNGF
Intramuscular injection
DRUGIsotonic-saline
Intramuscular injection
Sponsors
Aalborg University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Investigator)
Masking description
Double-blinded
Eligibility
Sex/Gender
ALL
Age
18 Years to 55 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy and pain free volunteers
Exclusion criteria
* Pregnancy * Drug addiction defined as the use of cannabis, opioids or other drugs * Previous neurologic, mental illnesses, or psychiatric diseases. * Past history of chronic pain in the musculoskeletal system (muscle, joint, cartilage, connective tissue) * Participation in other pain trials throughout the study period * Lack of ability to cooperate * Taking any analgesic 24 hours before the injections * Performing any strenuous leg exercise through out the study period causing sore muscles
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Muscle pain sensitivity (PPTs values) assessed by pressure algometer | Change from baseline at 3 week | Pressure pain thresholds (PPTs) are assessed over the dominant tibialis anterior muscle using a handhold pressure algometer. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Ischemic-induced pain intensity | Assessed right after the exercise has been performed, change from baseline at 3 weeks | Subjects perform a repeated static exercise with their dominant leg while a cuff is mounted over the knee to occlude the blodflow from the muscle (ischemia). Subjects subsequently rate their perceived pain intensity verbally on a 11-point numeric rating scale (NRS) rating from 0 (no pain) to 10 (worst pain imaginable). |
| Functional muscle pain | Change from baseline at 3 weeks | Subjects evaluate their muscle pain during movement using a 7-point Likert Scale for lower limp rating from 0 (a complete absence of pain) to 6 (a severe pain that limits my ability to move). |
| Conditioning pain modulation (CPM) efficacy | Change from baseline at 3 weeks | A test stimuli will be applied and compared with a test stimuli simultaneous a condition stimuli. |
| Temporal summation of pain | Change from baseline at 3 weeks | 10 repeated stimuli will be applied and subjects will be asked to rate the pain for each individual stimuli on a 11-point visual analogue scale (VAS) rating from 0 (no pain) to 10 (worst pain imaginable) |
Countries
Denmark
Contacts
Primary ContactLine Bay Sørensen, PhD. stud.
Outcome results
None listed