Using the Nociceptive Flexion Reflex to Diagnose Central Sensitization

De Nociceptieve Flexie Reflex Als Diagnostische Test Voor Centrale Sensitisatie

Observational University Ghent · NCT05321550

This study is testing if a reflex response can help doctors better understand central sensitization in people with chronic pain conditions like fibromyalgia, neck pain, and low back pain.

Quick facts

Study typeObservational
Enrollment240 (estimated)
Ages18 Years to 65 Years
SexAll
SponsorUniversity Ghent Academic / other
Locations1 site (Ghent)
Trial IDNCT05321550 on ClinicalTrials.gov

What this trial studies

This observational study aims to explore the nociceptive flexion reflex (NFR) as a potential diagnostic tool for central sensitization in patients with chronic pain conditions such as fibromyalgia, neck pain, and low back pain. It will assess whether changes in NFR thresholds and temporal summation are localized to the affected limbs or indicative of a broader central sensitization. The study will also evaluate pain perception and thresholds in response to various stimuli, comparing acute and chronic pain populations to better understand the mechanisms of pain. By examining these factors, the research seeks to clarify the relationship between peripheral and central sensitization in chronic pain patients.

Who should consider this trial

Good fit: Ideal candidates include individuals diagnosed with fibromyalgia, idiopathic neck pain, or idiopathic low back pain.

Not a fit: Patients with a history of severe pain complaints or significant orthopedic or neurological conditions may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved diagnostic methods for central sensitization, enhancing treatment strategies for chronic pain patients.

How similar studies have performed: While the approach of using NFR as a diagnostic tool is innovative, similar studies have shown promise in understanding pain mechanisms, suggesting potential for success.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria Fibromyalgia patients:

- diagnosed according to 2010 ACR-criteria

Inclusion Criteria neck pain patients:

- having idiopathic neck pain complaints or having grade 1 (pain, stiffness or tenderness of the neck and without objective physical abnormalities) or grade 2 (neck complaints and musculoskeletal disorders such as decreased range of motion and tender pain points) according to the Quebec Task Force on Whiplash Associated Disorders

Inclusion Criteria low back pain patients:

- having idiopathic low back pain complaints

Inclusion Criteria healthy controls:

* no history of serious pain complaints (e.g. severe migraine, fibromyalgia, etc.)
* no low back or neck pain complaints with an intensity of ≥2/10 on a visual analogue scale in the past year and of such severity that the daily activities were disrupted and a (para)medic was consulted

Exclusion Criteria:

* history of severe respiratory (e.g. cystic fibrosis), orthopedic (e.g. whiplash trauma), neurological (e.g. cerebrovascular incident), cardiovascular (e.g. severe hypertension), or endocrinological (e.g. diabetes) disorders
* recent psychological trauma (e.g. post-traumatic stress disorder)
* history of spinal surgery (e.g. lumbar discectomy), spinal trauma (e.g. vertebral fracture), or severe spinal deformities (e.g. spondylolisthesis)
* BMI ≥35 (due to potential difficulties in obtaining an NFR in severely overweight individuals)
* having pacemakers and defibrillators (absolute exclusion criteria for electrical stimulus stimulation, i.e. TENS)
* pregnancy, lactation, or within 1 year postpartum

Where this trial is running

Ghent

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Central SensitisationFibromyalgiaNeck PainLow Back PainWhiplash
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.