A Study of Contralateral Limb Block

Sciatic Block in Contralateral Limb for Treatment of Refractory Phantom and Residual Limb Pain; a Double-Blind Randomized Controlled Trial

This research is being done to determine if an anesthetic like Lidocaine, may be effective when injected around the sciatic nerve of the intact limb in patients with limb loss pain on the contralateral side.

Study Overview

• Status: Not yet recruiting
• Conditions: Limb Pain, Phantom
• Intervention / Treatment: Drug: Placebo; Drug: Lidocaine

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • Minnesota
    • Mankato, Minnesota, United States, 56001
      • Mayo Clinic Health System - Mankato
      • Contact: Cole Cheney, MD; Phone Number: 515-681-6338; Email: cheney.cole@mayo.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Lower extremity amputation performed more than 12 months before study enrollment
• PLP/RLP in affected amputated limb > 4 on NRS26
• Pain duration of more than 6 months despite a trial of conservative therapies for at least 2 months, including oral medications, topical medicines, physical therapy, and physical modalities (i.e., heat, cold, transcutaneous electrical nerve stimulation, phonophoresis)
• Willingness to undergo image guided diagnostic nerve block

Exclusion Criteria:

• Refusal / inability to participate or provide consent
• Contraindications to diagnostic nerve block
• Non-neurogenic source of PLP/RLP
• Current opioid use > 50 morphine milligram equivalents per day
• Any interventional pain treatment in the residual limb within the last 30 days
• Severe uncontrolled medical condition (i.e., hypertensive crisis, decompensated hypothyroidism)
• Use of investigational pain drug within past 30 days or other concurrent clinical trial enrollment

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Lidocaine Group; Subjects will receive a lidocaine injection in the back of their residual limb.	Drug: Lidocaine; 2 teaspoons of 2% lidocaine injection
Placebo Comparator: Sham Group; Subjects will receive a placebo injection in the back of their residual limb.	Drug: Placebo; Saline injection

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in pain	Measured using self-reported Numerical Rating Scale (NRS) where 0=no pain and 10=worst pain.	Baseline, 60 minutes post injection
Change in Functional Improvement	Measured using self-reported 20-item Orthotic and Prosthetics User's Survey (OPUS) Lower Extremity Functional Status Measurement survey. Total scores range from 0-100 scale with higher scores indicating a better outcome.	Baseline, 5 days post-injection

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in disability	Measured using self-reported 18-item The Groningen Activity Restriction Scale (GARS) that is a general disease independent instrument for measuring disability. Total scores range from 18-72. The higher the score the greater the disability.	Baseline, 5 days post-injection
Change in Pressure-Pain Algometry	Qualified study personnel will measure pain pressure threshold three times at each visit with an algometer on the participant's residual limb at the point of a maximal pain as indicated by the participant during pre-block physical examination, reported in kilopascal (kPa).	Baseline, 5 days post-injection
Step Count	Number of daily steps recorded by Modus StepWatch™ or Evolution EvoWalk™ fitted to the participant's prostheses	5 days post-injection

Collaborators and Investigators

• Sponsor: Mayo Clinic
• Investigators: Principal Investigator: Cole Cheney, MD, Mayo Clinic

Publications and helpful links

Helpful Links

• Mayo Clinic Clinical Trials

Study record dates

Study Major Dates

• Study Start (Estimated): May 1, 2024
• Primary Completion (Estimated): December 1, 2024
• Study Completion (Estimated): December 1, 2024

Study Registration Dates

• First Submitted: September 5, 2023
• First Submitted That Met QC Criteria: September 13, 2023
• First Posted (Actual): September 21, 2023

Study Record Updates

• Last Update Posted (Actual): April 2, 2024
• Last Update Submitted That Met QC Criteria: March 29, 2024
• Last Verified: March 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Nervous System Diseases; Postoperative Complications; Pain; Neurologic Manifestations; Neurobehavioral Manifestations; Perceptual Disorders; Pain, Postoperative; Phantom Limb; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Anti-Arrhythmia Agents; Central Nervous System Depressants; Peripheral Nervous System Agents; Sensory System Agents; Anesthetics; Membrane Transport Modulators; Anesthetics, Local; Voltage-Gated Sodium Channel Blockers; Sodium Channel Blockers; Lidocaine
• Other Study ID Numbers: 22-010792

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No