Clinical trial NCT03362827: Assessment of LTP-like Pain Amplification in Chronic Low Back Pain Patients
Official title: Assessment of Long-term Potentiation (LTP)-Like Pain Amplification in Chronic Low Back Pain Patients
Study type: OBSERVATIONAL
Overall status: UNKNOWN
Conditions: Low Back Pain
Keywords: Low back pain
Long-term potentiation
Hyperalgesia
Allodynia
Lead sponsor: Peking University People's Hospital
Sponsor class: OTHER
First posted: 2017-12-05
Enrollment: 50
Sex: ALL
Minimum age (years): 20
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: yes
Observational model: OTHER
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: 1. Chronic low back pain patients Age 21-80 years old.People must have experienced low back pain for at least 3 months and have reported a minimal pain level of 30 (pain threshold) on the 0-100 pain numerical rating scale (NRS) in the last 7 days.Patients were excluded if they had taken pain medications on the day of the assessment or if they had serious spinal pathologies, such as fractures, tumors or inflammatory diseases. Those who were pregnant, patients with cancer and those with a cardiac pacemaker were also excluded.
2. Healthy volunteers. Age 21-80 years old.These participants must not have presented episodes of low back pain for more than 7 days in the last 12 months.

Brief summary: The present study is aimed to assess the LTP-like pain amplification in chronic low back pain patients to explore the central and peripheral effect for pain LTP.

Detailed description: This study is a cross-sectional study. Two groups, including low back pain group and healthy subjects group will be arranged in this study. 50 subjects will be recruited in each group, The healthy subjects were matched for sex and age in relation to the low back pain group. Conditioning electrical stimulation (100 Hz, repeated 5 times with 10 s intervals, 500 impulses) using circular pin electrodes will be used in both groups to induce LTP-like pain amplification. The pain intensity changes to pinprick and light touch stimuli will be compared between two groups.

Eligibility criteria: 1. Chronic low back pain patients

   Inclusion Criteria:
   * Age 21-80 years old.
   * People must have experienced low back pain for at least 3 months and have reported a minimal pain level of 30 (pain threshold) on the 0-100 pain numerical rating scale (NRS) in the last 7 days.

   Exclusion Criteria:
   * Age below 21 or over 80 years old.
   * Patients were excluded if they had taken pain medications on the day of the assessment or if they had serious spinal pathologies, such as fractures, tumors or inflammatory diseases, such as ankylosing spondylitis, nerve root compromise confirmed by clinical neurological tests or severe cardiorespiratory diseases. Those who were pregnant, patients with cancer and those with a cardiac pacemaker were also excluded.
2. Healthy volunteers.

Inclusion Criteria:

* Age 21-80 years old.
* These participants must not have presented episodes of low back pain for more than 7 days in the last 12 months.

Exclusion Criteria:

* Age below 21 or over 80 years old.
* These participants have presented episodes of low back pain for more than 7 days in the last 12 months.

Primary outcomes:
measure: Change of pain intensity to pinprick stimuli
timeFrame: The pinprick sensation will be measured three times before and six times after the conditioning electrical stimulation with 10 minutes interval throughout the experiment (90 minutes).
Secondary outcomes:
measure: Perception Features of conditioning electrical stimulation (CES)
timeFrame: All subjects will rate the pain ratings during the 50 seconds stimulation.
measure: Change of pain intensity to light-stroking stimuli
timeFrame: The light-touch sensation will be measured three times before and six times after the conditioning electrical stimulation with 10 minutes interval throughout the experiment (90 minutes).
measure: Change of pain intensity to single electrical stimulation (SES)
timeFrame: The pain ratings to SES will be measured three times before and six times after the conditioning electrical stimulation with 10 minutes interval throughout the experiment (90 minutes).
Other outcomes:
Locations:
Study officials:
affiliation: Peking University People's Hospital
name: Chenjun Liu, Ph.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Biurrun Manresa JA, Morch CD, Andersen OK. Long-term facilitation of nociceptive withdrawal reflexes following low-frequency conditioning electrical stimulation: a new model for central sensitization in humans. Eur J Pain. 2010 Sep;14(8):822-31. doi: 10.1016/j.ejpain.2009.12.008. Epub 2010 Jan 27.
citation: Mouraux A, Iannetti GD, Plaghki L. Low intensity intra-epidermal electrical stimulation can activate Adelta-nociceptors selectively. Pain. 2010 Jul;150(1):199-207. doi: 10.1016/j.pain.2010.04.026. Epub 2010 May 26.
citation: Morch CD, Hennings K, Andersen OK. Estimating nerve excitation thresholds to cutaneous electrical stimulation by finite element modeling combined with a stochastic branching nerve fiber model. Med Biol Eng Comput. 2011 Apr;49(4):385-95. doi: 10.1007/s11517-010-0725-8. Epub 2011 Jan 5.
citation: Melzack R. The short-form McGill Pain Questionnaire. Pain. 1987 Aug;30(2):191-197. doi: 10.1016/0304-3959(87)91074-8.
citation: Xia W, Morch CD, Andersen OK. Test-Retest Reliability of 10 Hz Conditioning Electrical Stimulation Inducing Long-Term Potentiation (LTP)-Like Pain Amplification in Humans. PLoS One. 2016 Aug 16;11(8):e0161117. doi: 10.1371/journal.pone.0161117. eCollection 2016.