Short and Long Term Exposure to Unique, Time-Varying Pulsed Electro-Magnetic Fields in Refractory Carpal Tunnel Syndrome

September 20, 2007 updated by: Weintraub, Michael I., MD, FACP, FAAN

Short and Long Term Exposure to Unique, Time-Varying Pulsed Electro-Magnetic Fields in Refractory Carpal Tunnel Syndrome (Cts): A Randomized, Placebo-Controlled Trial With Secondary Bayesian Modification

Pulsed electromagnetic fields (PEMF) have been approved by FDA and are utilized currently in treating non-union fractures, neurogenic bladder and musculoskeletal pains. Based on 2 prior pilot studies (open label) demonstrating reduction in neuropathic pain from carpal tunnel syndrome we decided to perform a placebo-controlled trial, randomized for 2 months utilizing a wrist PEMF device attached by Velcro for 4 hours/day.

Study Overview

Detailed Description

INTRODUCTION:

Entrapment of the median nerve at the wrist is the most common cause of sensory and motor disturbance in the hands and can be progressively disabling.1,2 Complex mechanisms of compression and ischemia exist that adversely influence the large A myelinated fibers and small unmyelinated nociceptive C fibers. From a pathophysiological standpoint, neuropathic pain (numbness, tingling and burning, NP) is believed secondary to ectopic firing of nociceptive afferent unmyelinated C-fiber axons that are undergoing degeneration.3 Microneurography has confirmed that dysregulated expression of sodium and calcium channels, which accumulate at site of injury, are responsible for ectopic depolarization.3,4,53,54 When conventional therapy of splinting and pharmacotherapy fail, surgical decompression has been offered for moderate-severe cases. While usually successful, it is associated with significant complications, limitations and costs.5,6,7 Thus, the search for reliable and new therapeutic strategies is appealing.

Substantial evidence exists that time-varying magnetic fields produce biological effects by safely inducing extremely low-frequency (ELF) small electrical eddy currents within the tissues that can depolarize, repolarize and hyperpolarize neurons.8,9,10,11,12

Prior pilot data using static13 and pulsed magnetic fields (PEMF)14,15 directed to the carpal tunnel region significantly reduced NP. Since a new, novel device became commercially available that produced a combination of static and time-varying magnetic fields simultaneously, it was hypothesized that this energy could be directed into the wrists and potentially influence not only NP scores, but also modulate neuronal distal latencies (neurotransmission).

DEVICE:

DESCRIPTION: (FIGURE 1) This patented device (Biaxial Super Mini [Mx2R] by Nikken, Inc.) measures 2" in diameter and 1" in height and is worn with a Velcro strap similar to a wristwatch. It is noiseless and nonthermal. Its main component is a spherical permanent magnet, 1150G, 3/8" in diameter that rotates in two perpendicular directions simultaneously producing biaxial magnetic rotation (MX2R) and oscillating polarities up to 1,200 rpm-20 times per second. It is driven by a 2 V DC micro-motor which is shielded one inch away and produces a negligible back EMF. The device is powered by three ¼ AAA rechargeable NiMH (Nickel Metal Hydride) batteries

Randomized double blind placebo-controlled device with primary parameters of pain and sleep interupption scores, NPS scale and secondary parameters of neurological exam changes, nerve conduction latencies of median nerve, dynamometry, finger gauge pressures, CPT and PGIC were compared at baseline and end of two months. Patients were given a free "active" device gratis at end of study.

Study Type

Interventional

Enrollment

50

Phase

  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • New York
      • Briarcliff, New York, United States, 10510
        • Michael I. Weintraub MD, PC

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Intractable neuropathic pain in median nerve innervated hand for at least 3 months;
  • Abnormal neurological examination compatible with diagnosis of CTS

Exclusion Criteria:

  • Post-surgical failures,
  • Pregnancy,
  • Pts with pacemaker

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

What is the study measuring?

Primary Outcome Measures

Outcome Measure
VAS Pain scores 0-10 (leikert scale)
VAS Sleep interrupption 0-10
Neuropathic Pain scale (NPS)

Secondary Outcome Measures

Outcome Measure
Neurological Exam
Median nerve distal latencies (CMAP/SNAP)
Hand help Dynamometry and Finger gauge pressures
CPT (Neurometer)
PGIC

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Study Chair: Steven P. Cole, PhD, Statistician

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

June 1, 2004

Study Completion

July 1, 2005

Study Registration Dates

First Submitted

January 13, 2006

First Submitted That Met QC Criteria

January 13, 2006

First Posted (Estimate)

January 16, 2006

Study Record Updates

Last Update Posted (Estimate)

September 21, 2007

Last Update Submitted That Met QC Criteria

September 20, 2007

Last Verified

September 1, 2007

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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