The Effect of Prior Muscle Activation on the Compound Muscle Action Potential (CMAP)- Implications for Routine Nerve Conduction Studies (NCS) and Serial NCS

Loma Linda University1 个研究点分布在 1 个国家目标入组 6 人开始时间: 2010年10月1日最近更新: 2019年8月14日

适应症

干预措施

试验速览

阶段: 不适用
状态: 已完成
发起方: Loma Linda University
入组人数: 6
试验地点: 1
主要终点: Ulnar-Hypothenar CMAP Amplitude

研究概览研究设计入排标准研究组 & 干预措施结局指标研究者研究点记录与标识符相似试验

研究概览

简要总结

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.

详细描述

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.

研究设计

研究类型: Interventional
分配方式: Non Randomized
干预模型: Crossover
主要目的: Basic Science
盲法: None

入排标准

年龄范围: 18 Years 至 49 Years（Adult）
性别: All
接受健康志愿者: 是

入选标准

•Normal, healthy volunteers
•Age 18-49

排除标准

•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

研究组 & 干预措施

Activation of Hypothenar Eminence

Other

Each subject will perform maximum, voluntary, isometric muscle activation (of the target muscle) for each of various lengths of time ("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]).

干预措施: Hypothenar muscle activation--maximum, voluntary, isometric (Other)

Activation of Thenar Eminence

Other

干预措施: Thenar muscle activation--maximum, voluntary, isometric (Other)

Activation of Extensor Digitorum Brevis

Other

干预措施: EDB muscle activation--maximum, voluntary, isometric (Other)

Maintain Relaxation of the Opposite Side

Placebo Comparator

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.

干预措施: Relaxation of muscle (Other)