Clinical trial NCT03463759: Pain Inhibition and Facilitation in Recurrent Low Back Pain
Official title: Pro-Nociceptive and Anti-Nociceptive Mechanisms Across an Episode of Recurrent Low Back Pain
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Recurrent Low Back Pain
Healthy
Lead sponsor: Aalborg University
Sponsor class: OTHER
First posted: 2018-03-13
Enrollment: 60
Sex: ALL
Minimum age (years): 18
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Population recruited from university, college, and wider Aalborg community

Brief summary: This study evaluates psychophysical measures of pain inhibition and facilitation, along with cortical responses to different sensory stimuli, in patients with recurrent low back pain and matched healthy individuals.

Detailed description: Pain inhibitory and facilitatory mechanisms have been suggested to play a role in the development of persistent low back pain; however, there is still debate on when changes in these mechanisms occur. Similarly, evoked cortical responses can reflect neuroplastic changes in pain processing regions, which are also thought to play a role in the transition to persistent pain, but there is also debate on when these neuroplastic changes develop relative to low back pain. Therefore, this study will use patients with an intermediary clinical pain state, recurrent low back pain, and matched healthy control participants, to investigate within and between subject differences in pain inhibitory, facilitatory and neuroplastic mechanisms.

Eligibility criteria: Inclusion:

* Healthy men and women
* Aged 18-60 years
* No previous back pain OR \>1 previous episode of low back pain in past 12 months
* No current back pain OR Pain in the region posteriorly between the inferior border of the 12th rib and the lower gluteal fold (low back pain) at time of recruitment lasting \>24 hours
* Able to speak, read and understand English

Exclusion:

* Pregnancy
* First episode of low back pain
* Low back pain associated with menstruation
* Chronic low back pain (continuous pain episode for \>3 months)
* Currently seeking active treatment for low back pain
* Red flags symptoms
* Drug addiction defined as the use of cannabis, opioids or other drugs
* Current or previous neurologic, musculoskeletal, mental, or other illnesses which may affect the trial
* Current or previous chronic or recurrent pain condition other than low back pain
* Current regular use of analgesic or other medication which may affect the trial
* Lack of ability to cooperate
* Recent history of acute pain particularly in the lower limbs (unless related to LBP)
* Abnormally disrupted sleep in 24 hours preceding experiment

Primary outcomes:
measure: Conditioned Pain Modulation
timeFrame: Day 0 vs. Day 28
measure: Temporal Summation of Pain
timeFrame: Day 0 vs. Day 28
Secondary outcomes:
measure: Pressure Pain Thresholds
timeFrame: Day 0 vs. Day 28
measure: Thermal Pain Thresholds
timeFrame: Day 0 vs. Day 28
measure: Two Point Discrimination
timeFrame: Day 0 vs. Day 28
measure: Proprioceptive Weighting
timeFrame: Day 0 vs. Day 28
measure: Sensory Evoked Potentials
timeFrame: Day 0 vs. Day 28
Other outcomes:
measure: Affective Regulation
timeFrame: Day 0 vs. Day 28
measure: Attentional Regulation
timeFrame: Day 0 vs. Day 28
Locations:
city: Aalborg
country: Denmark
facility: CNAP, SMI, Aalborg University
Study officials:
affiliation: Aalborg University
name: Megan E McPhee, BPhty MSc
role: PRINCIPAL_INVESTIGATOR
References:
citation: McPhee ME, Graven-Nielsen T. Positive affect and distraction enhance whereas negative affect impairs pain modulation in patients with recurrent low back pain and matched controls. Pain. 2022 May 1;163(5):887-896. doi: 10.1097/j.pain.0000000000002442.