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The Effect of Prior Muscle Activation on the Compound Muscle Action Potential (CMAP)

This study is ongoing, but not recruiting participants.
Sponsor:
Information provided by (Responsible Party):
Gordon Peterson, Loma Linda University
ClinicalTrials.gov Identifier:
NCT01182558
First received: August 12, 2010
Last updated: October 13, 2011
Last verified: October 2011
History of Changes
  Purpose

The purpose of this investigator-initiated study is to determine the effect of prior muscle activation on the response obtained by nerve conduction studies (the compound muscle action potential [CMAP]) looking at the amplitude, area, and duration of the CMAP and evaluating the length of time the CMAP is larger than at baseline. On the opposite side, the corresponding CMAP will be tested periodically, but there will be no muscle activation on that side.

Null Hypothesis: While controlling all possible technical and other known physiological variables, prior activation of a muscle has no effect on the amplitude and area of the compound muscle action potential (CMAP); and the CMAP does not change over time in the relaxed muscle (on the opposite side).

The investigators suspect that there is an effect of prior activation of the muscle on the subsequent CMAP recorded from that muscle.


Condition Intervention
Normal Healthy Subjects
 Other: Hypothenar muscle activation--maximum, voluntary, isometric
Other: Thenar muscle activation--maximum, voluntary, isometric
Other: EDB muscle activation--maximum, voluntary, isometric
Other: Relaxation of muscle

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Crossover Assignment
Masking: Open Label
Primary Purpose: Basic Science
Official Title: The Effect of Prior Muscle Activation on the Compound Muscle Action Potential (CMAP)- Implications for Routine Nerve Conduction Studies (NCS) and Serial NCS

Further study details as provided by Loma Linda University:

Primary Outcome Measures:
  • Ulnar-Hypothenar CMAP Amplitude [ Time Frame: Immediate, 5 sec, 10 sec, 15 sec, 20 sec, 30 sec, 60 sec, 90 sec, 2 minutes, and each minute up to 40 minutes (or return to pre-activation value) ] [ Designated as safety issue: No ]
    Amplitude (baseline to negative peak) of the compound muscle action potential (CMAP) recorded from the hypothenar eminence after stimulation of the ulnar nerve at the wrist

  • Ulnar-Hypothenar CMAP Area [ Time Frame: Immediate, 5 sec, 10 sec, 15 sec, 20 sec, 30 sec, 60 sec, 90 sec, 2 minutes, and each minute up to 40 minutes (or return to pre-activation value) ] [ Designated as safety issue: No ]
    Area (under the negative curve) of the compound muscle action potential (CMAP) recorded from the hypothenar eminence after stimulation of the ulnar nerve at the wrist

  • Median-Thenar CMAP Amplitude [ Time Frame: Immediate, 5 sec, 10 sec, 15 sec, 20 sec, 30 sec, 60 sec, 90 sec, 2 minutes, and each minute up to 40 minutes (or return to pre-activation value) ] [ Designated as safety issue: No ]
    Amplitude (baseline to negative peak) of the compound muscle action potential (CMAP) recorded from the thenar eminence after stimulation of the median nerve at the wrist

  • Median-Thenar CMAP Area [ Time Frame: Immediate, 5 sec, 10 sec, 15 sec, 20 sec, 30 sec, 60 sec, 90 sec, 2 minutes, and each minute up to 40 minutes (or return to pre-activation value) ] [ Designated as safety issue: No ]
    Area (under the negative curve) of the compound muscle action potential (CMAP) recorded from the thenar eminence after stimulation of the median nerve at the wrist

  • Peroneal-EDB CMAP Amplitude [ Time Frame: Immediate, 5 sec, 10 sec, 15 sec, 20 sec, 30 sec, 60 sec, 90 sec, 2 minutes, and each minute up to 40 minutes (or return to pre-activation value) ] [ Designated as safety issue: No ]
    Amplitude (baseline to negative peak) of the compound muscle action potential (CMAP) recorded from the extensor digitorum brevis muscle (EDB) after stimulation of the peroneal nerve at the ankle

  • Peroneal-EDB CMAP Area [ Time Frame: Immediate, 5 sec, 10 sec, 15 sec, 20 sec, 30 sec, 60 sec, 90 sec, 2 minutes, and each minute up to 40 minutes (or return to pre-activation value) ] [ Designated as safety issue: No ]
    Area (under the negative curve) of the compound muscle action potential (CMAP) recorded from the extensor digitorum brevis muscle (EDB) after stimulation of the peroneal nerve at the ankle


Secondary Outcome Measures:
  • Ulnar-Hypothenar CMAP Duration [ Time Frame: Immediate, 5 sec, 10 sec, 15 sec, 20 sec, 30 sec, 60 sec, 90 sec, 2 minutes, and each minute up to 40 minutes (or return to pre-activation value) ] [ Designated as safety issue: No ]
    Duration (of the negative curve) of the compound muscle action potential (CMAP) recorded from the hypothenar eminence after stimulation of the ulnar nerve at the wrist

  • Median-Thenar CMAP Duration [ Time Frame: Immediate, 5 sec, 10 sec, 15 sec, 20 sec, 30 sec, 60 sec, 90 sec, 2 minutes, and each minute up to 40 minutes (or return to pre-activation value) ] [ Designated as safety issue: No ]
    Duration (of the negative curve) of the compound muscle action potential (CMAP) recorded from the thenar eminence after stimulation of the median nerve at the wrist

  • Peroneal-EDB CMAP Duration [ Time Frame: Immediate, 5 sec, 10 sec, 15 sec, 20 sec, 30 sec, 60 sec, 90 sec, 2 minutes, and each minute up to 40 minutes (or return to pre-activation value) ] [ Designated as safety issue: No ]
    Duration (of the negative curve) of the compound muscle action potential (CMAP) recorded from the extensor digitorum brevis muscle (EDB) after stimulation of the peroneal nerve at the ankle

  • Size of the CMAP from the Contralateral Limb Muscle While at Rest [ Time Frame: Record periodically (every 1-15 minutes) ] [ Designated as safety issue: No ]
    The amplitude, area, and duration of the compound muscle action potential (CMAP) recorded from the contralateral muscle (Ulnar-Hypothenar, Median-Thenar, or Peroneal-EDB) will be determined as this contralateral muscle stays at rest.

  • F Wave Size and Persistence [ Time Frame: Periodically ] [ Designated as safety issue: No ]
    F waves may be determined and the size and persistence of the F wave may be determined at baseline and if the amplitude of the direct response recorded from the muscle (on either the side of muscle activation or the side continuing at rest) with nerve stimulation changes by more than a small amount.


Estimated Enrollment: 20
Study Start Date: October 2010
Estimated Study Completion Date: May 2012
Primary Completion Date: May 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Activation of Hypothenar Eminence
Each subject will perform maximum, voluntary, isometric muscle activation (of the target muscle) for each of various durations ("single brief muscle twitch," 2 seconds, 5 seconds, 10 seconds, and 20 seconds [two epochs of 10 seconds of muscle activation with 1-2 seconds of rest between the two epochs]).
 Other: Hypothenar muscle activation--maximum, voluntary, isometric
Each subject will perform maximum, voluntary, isometric muscle activation (of the target muscle) for each of various durations ("single brief muscle twitch," 2 seconds, 5 seconds, 10 seconds, and 20 seconds [two epochs of 10 seconds of muscle activation with 1-2 seconds of rest between the two epochs]).
Activation of Thenar Eminence
Each subject will perform maximum, voluntary, isometric muscle activation (of the target muscle) for each of various durations ("single brief muscle twitch," 2 seconds, 5 seconds, 10 seconds, and 20 seconds [two epochs of 10 seconds of muscle activation with 1-2 seconds of rest between the two epochs]).
 Other: Thenar muscle activation--maximum, voluntary, isometric
Each subject will perform maximum, voluntary, isometric muscle activation (of the target muscle) for each of various durations ("single brief muscle twitch," 2 seconds, 5 seconds, 10 seconds, and 20 seconds [two epochs of 10 seconds of muscle activation with 1-2 seconds of rest between the two epochs]).
Activation of Extensor Digitorum Brevis
Each subject will perform maximum, voluntary, isometric muscle activation (of the target muscle) for each of various durations ("single brief muscle twitch," 2 seconds, 5 seconds, 10 seconds, and 20 seconds [two epochs of 10 seconds of muscle activation with 1-2 seconds of rest between the two epochs]).
 Other: EDB muscle activation--maximum, voluntary, isometric
Each subject will perform maximum, voluntary, isometric muscle activation (of the target muscle) for each of various durations ("single brief muscle twitch," 2 seconds, 5 seconds, 10 seconds, and 20 seconds [two epochs of 10 seconds of muscle activation with 1-2 seconds of rest between the two epochs]).
Placebo Comparator: Maintain Relaxation of the Opposite Side
While the muscle of the right side is activated periodically and the compound muscle action potential is tested frequently, the muscle on the left side is maintained at rest and the compound muscle action potential is tested infrequently.
 Other: Relaxation of muscle
The muscle on the opposite side will be maintained at rest.

Detailed Description:

Nerve conduction studies (NCS) will be performed with supramaximal nerve stimulation, surface stimulation, surface recording, and with best possible technique controlling as many variables as possible including the location of the recording electrodes and with a warm muscle and nerve (measuring temperature at the skin) in each of 3 "arms" of the study:

  • ulnar nerve stimulation at the wrist recording from the hypothenar eminence,
  • median nerve stimulation at the wrist recording from the thenar eminence, and
  • peroneal nerve stimulation at the ankle recording from the extensor digitorum brevis muscle.

NCS will be performed in a rested muscle (rested for 15 minutes or longer) and then multiple times for up to 40 minutes after maximum isometric contraction (activation) of the tested muscle for a defined length of time. The defined lengths of muscle activation include:

  • "a brief twitch" (activation for a fraction of a second),
  • 2 seconds,
  • 5 seconds,
  • 10 seconds, and
  • 20 seconds (two epochs of 10 seconds of activation with 1-2 seconds of rest between the two epochs).

The CMAP will be recorded multiple times from the muscle which was activated (pre-activation; as well as post-activation at multiple times after muscle activation: immediately, 5 sec, 10 sec, 15 sec, 20 sec, 30 sec, 60 sec, 90 sec, 2 minutes, and every minute up to as long as 40 minutes). Similar recordings will be made after each of the 5 durations of muscle activation ("a brief twitch," 2 seconds, 5 seconds, 10 seconds, and 20 seconds) of each of the three muscles (hypothenar, thenar, and EDB). CMAP amplitude (baseline to negative peak), area (under the negative curve), and duration (of the negative CMAP) will each be measured at each timepoint; and skin temperature in the region of the "active" recording electrode will be measured. Each data type will be compared over time in a series, identified as muscle from which recorded, duration of muscle activation performed prior to the recording, and time after the end of muscle activation.

On a few occasions during the testing of the CMAP on the side on which the muscle is activated, there will be recording of the CMAP from the corresponding muscle on the opposite side, but that second side will be relaxed the entire time of testing (for 4-5 hours).

If the CMAP changes more than a small amount on either side, F waves may be tested while the muscle is at rest.

Each subject will participate in each of the 3 "arms." Testing for the five series of recordings from each muscle is anticipated to take 4-5 hours, i.e., after screening, 12-15 hours total for testing the 3 muscles in each subject.

  Eligibility

Ages Eligible for Study:   18 Years to 49 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Normal, healthy volunteers
  • Age 18-49

Exclusion Criteria:

  • Localized or generalized neuromuscular disorder
  • History of neuropathy
  • History of diabetes
  • History of prior injuries or surgeries of the back, neck, or limbs to be tested which in the opinion of the investigator might have the potential to influence the compound muscle action potential
  • Medications other than eyedrops or non-steroidal anti-inflammatory agents (as needed) or contraceptive agents or non-steroidal topical agents
  • Abnormalities by screening nerve conduction studies
  • Anomalous innervation of the tested extensor digitorum brevis via screening nerve conduction studies
  • Use of caffeine or nicotine within 8 hours of testing
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT01182558

Locations
United States, California
Neurology - Faculty Physicians and Surgeons of Loma Linda University School of Medicine
Loma Linda, California, United States, 92354
Sponsors and Collaborators
Loma Linda University
Investigators
Principal Investigator: Gordon W. Peterson, MD Neurology, Faculty Physicians and Surgeons of Loma Linda University School of Medicine
  More Information

No publications provided

Responsible Party: Gordon Peterson, Professor of Neurology, Loma Linda University
ClinicalTrials.gov Identifier: NCT01182558     History of Changes
Other Study ID Numbers: 5100161
Study First Received: August 12, 2010
Last Updated: October 13, 2011
Health Authority: United States: Institutional Review Board

Keywords provided by Loma Linda University:
Muscle
Activation
Effect
Compound muscle action potential

ClinicalTrials.gov processed this record on October 17, 2012