Prediction of Outcome of Interventional Pain Management (POINTPM)

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

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.

Study Overview

• Status: Not yet recruiting
• Conditions: Low Back Pain; Chronic Pain; Neck Pain
• Intervention / Treatment: Device: nociceptive flexion reflex (NFR) threshold ("Paintracker", Dolosys GmbH, Berlin, Germany)

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.

• Study Type: Observational
• Enrollment (Anticipated): 350

Contacts and Locations

• Study Contact: Name: Benno Rehberg-Klug, MD; Phone Number: +41223723476; Email: benno.rehberg-klug@hcuge.ch
• Study Contact Backup: Name: Stanislas Mathivon; Email: stanislas.mathivon@hcuge.ch

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

• 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

Description

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

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
observational cohort; patients undergoing interventional pain management procedures	Device: nociceptive flexion reflex (NFR) threshold ("Paintracker", Dolosys GmbH, Berlin, Germany); measurement of the NFR threshold using the "Paintracker" device; Other Names: R3 reflex

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ROC-AUC for incidence of pain reduction>30% at 1 week	Primary study outcome is the diagnostic accuracy of the NFR threshold, measured as area under the "receiver operating characteristic ROC" curve, for the following main pain management outcome: "pain reduction of 30% one week after the interventional procedure	1 week

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ROC-AUC for incidence of pain reduction>30% at 1 month	Area Under the curve (AUC) of the receiver-operating characteristic (ROC) of the relation between NFR reflex threshold and the incidence of pain reduction>30% at 1 month	1 month
ROC-AUC for incidence of pain reduction>30% at 3 months	Area Under the curve (AUC) of the receiver-operating characteristic (ROC) of the relation between NFR reflex threshold and the incidence of pain reduction>30% at 3 months	3 months
ROC-AUC for incidence of pain reduction>30% at 6 months	Area Under the curve (AUC) of the receiver-operating characteristic (ROC) of the relation between NFR reflex threshold and the incidence of pain reduction>30% at 6 months	6 months
ROC-AUC for physical functioning at 1 week		1 week
ROC-AUC for emotional functioning at 1 week		1 week
ROC-AUC for patient rating of improvement and satisfaction at 1 week		1 week
adverse events of interventional pain management		1 week
patient disposition at 1 week, 1,3, and 6 months	The presence or unexcused absence of the patient at each consultation visit is noted	6 months

Collaborators and Investigators

• Sponsor: Benno Rehberg-Klug
• Investigators: Principal Investigator: Benno Rehberg-Klug, MD, Hôpitaux Universitaires de Genève

Study record dates

Study Major Dates

• Study Start (Anticipated): January 1, 2024
• Primary Completion (Anticipated): September 1, 2025
• Study Completion (Anticipated): September 1, 2025

Study Registration Dates

• First Submitted: December 2, 2015
• First Submitted That Met QC Criteria: May 12, 2016
• First Posted (Estimate): May 17, 2016

Study Record Updates

• Last Update Posted (Actual): May 16, 2023
• Last Update Submitted That Met QC Criteria: May 13, 2023
• Last Verified: May 1, 2023

More Information

Terms related to this study

• Keywords: nociceptive flexion reflex; interventional pain management
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Back Pain; Low Back Pain; Chronic Pain; Neck Pain
• Other Study ID Numbers: 15-072

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED