Clinical trial NCT02774694: Prediction of Outcome of Interventional Pain Management
Official title: Observational Study of the Nociceptive Flexion Reflex Threshold to Predict Outcome After Interventional Pain Management Procedures in Patients With Chronic Back and Neck Pain. A Study of Diagnostic Accuracy
Study type: OBSERVATIONAL
Overall status: NOT_YET_RECRUITING
Conditions: Low Back Pain
Neck Pain
Chronic Pain
Keywords: nociceptive flexion reflex
interventional pain management
Lead sponsor: University Hospital, Geneva
Sponsor class: OTHER
First posted: 2016-05-17
Enrollment: 350
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Included will be patients treated by the interventional pain management team of the department of anaesthesiology of the Geneva University Hospitals HUG

Brief summary: Interventional pain management for back and neck pain is widely used, but the indications and relative merits of these techniques rest subject to discussion. This study aims to identify prognostic criteria for patients who might specifically benefit from interventional pain management. Specifically, the nociceptive reflex threshold will be investigated, which is a measure of central sensibilisation and thus a potentially important prognostic factor.

Detailed description: Interventional pain management is resource-intensive and carries non-negligible risks. Not all patients profit equally from such procedures. For those who do not benefit, the risk of potential complications is futile, and the resources are wasted. Therefore, a possibility to distinguish responding patients from non-responders would be important.

Central pain sensitization has been related to poor outcome, and electrical pain and reflex thresholds are a good measure of pain hypersensitivity at least in chronic low back pain. Especially the nociceptive flexion reflex (NFR) threshold has been identified to correlate well with central pain hypersensibility. Successful interventional pain treatment has been shown to reverse central hypersensibility as measured by the NFR threshold.

NFR threshold, in contrast to pain threshold, seems to be a measure independent of psychological factors. Thus the NFR threshold could give information independent of psychological factors in order to predict poor outcome of interventional pain management procedures.

The study will be a prospective observational trial of diagnostic accuracy.

Eligibility criteria: Inclusion Criteria:

* patients with chronic low back or neck pain (duration \>3 months)
* scheduled for the following interventions: epidural injection, facet block, medial branch block, facet radiofrequency denervation, spinal cord stimulator implantation

Exclusion Criteria:

* inability to understand the patient information or the study questionnaires
* patients \<18 years old
* patients with implanted pacemakers or defibrillators

Primary outcomes:
measure: ROC-AUC for incidence of pain reduction>30% at 1 week
timeFrame: 1 week
Secondary outcomes:
measure: ROC-AUC for incidence of pain reduction>30% at 1 month
timeFrame: 1 month
measure: ROC-AUC for incidence of pain reduction>30% at 3 months
timeFrame: 3 months
measure: ROC-AUC for incidence of pain reduction>30% at 6 months
timeFrame: 6 months
measure: ROC-AUC for physical functioning at 1 week
timeFrame: 1 week
measure: ROC-AUC for emotional functioning at 1 week
timeFrame: 1 week
measure: ROC-AUC for patient rating of improvement and satisfaction at 1 week
timeFrame: 1 week
measure: adverse events of interventional pain management
timeFrame: 1 week
measure: patient disposition at 1 week, 1,3, and 6 months
timeFrame: 6 months
Other outcomes:
Locations:
Study officials:
affiliation: University Hospital, Geneva
name: Benno Rehberg-Klug, MD
role: PRINCIPAL_INVESTIGATOR
References: