Amplitude, area and duration of the compound muscle action potential change in different ways over the length of the ulnar nerve (original) (raw)

Conduction in ulnar nerve bundles that innervate the proximal and distal muscles: a clinical trial

BMC neurology, 2010

This study aims to investigate and compare the conduction parameters of nerve bundles in the ulnar nerve that innervates the forearm muscles and hand muscles; routine electromyography study merely evaluates the nerve segment of distal (hand) muscles. An electrophysiological evaluation, consisting of velocities, amplitudes, and durations of ulnar nerve bundles to 2 forearm muscles and the hypothenar muscles was performed on the same humeral segment. The velocities and durations of the compound muscle action potential (CMAP) of the ulnar nerve bundle to the proximal muscles were greater than to distal muscles, but the amplitudes were smaller. Bundles in the ulnar nerve of proximal muscles have larger neuronal bodies and thicker nerve fibers than those in the same nerve in distal muscles, and their conduction velocities are higher. The CMAPs of proximal muscles also have smaller amplitudes and greater durations. These findings can be attributed to the desynchronization that is caused b...

Nerve Conduction Studies in the Upper Limb in the Malwa Region-Normative Data

JOURNAL OF CLINICAL AND DIAGNOSTIC RESEARCH, 2013

Objective: To establish the normal electrophysiological data for the median and the ulnar nerves in normal healthy adults in the Malwa region of Punjab, India. Methods: Nerve conduction studies were performed prospectively in the upper limbs of 100 carefully screened, healthy individuals of either sex, who were between the ages of 20 and 60 years, by using a standardized technique. Results: Motor studies: The median distal latency (DL) in men was 3.4 (0.2) ms, the amplitude (CMAPA) was 10.80 (2.8) mV, the conduction velocity (MNCV) was 55.6 (2.5) m/s and the F-wave (min latency) was 27.57±2.54(21.5-34.2). In the ulnar nerve , the motor DL was 2.34 (0.25) ms, the amplitude (CMAPA) was 9.8(2.6) mV, MNCV was 63.4 (3.0) m/s and the F-Wave(min latency) was 26.29±2.12(21.6-34.7). In the sensory studies, the median nerve DL was 2.0(0.35) ms, SNCV was 53.4±3.0 m/s and the amplitude (SNAPA)was 59.3 (16.4) µV for men and it was 68.7(28.4) µV for women. For the ulnar nerve in men, the DL was 1.85(0.25)ms, SNCV was 55.5 (4.1) m/s and the amplitude(SNAPA) was 55.5 (18.4) µV for men and it was 64.9 (16.8) µV for women. Only the gender showed a statistically significant effect on the sensory nerve action potential for the median (p < 0.04) and the ulnar nerves (p < 0.041). Conclusion: The normative conduction parameters of the commonly tested nerves in the upper limb were established in our EMG lab. The mean motor nerve conduction parameters for the median and the ulnar nerves correlated favourably with the existing literature data. However, for the sensory nerves, a higher value for the nerve action potential amplitude was demonstrated in this study.

Reference data for ulnar nerve short segment conduction studies at the elbow

Muscle & Nerve, 2011

Introduction: The aim of this study was to generate reference data for ulnar nerve short segment conduction studies (SSCSs) at 2-cm intervals. Methods: Ulnar nerve SSCS data were collected from dominant and non-dominant arms of 200 healthy volunteers. The effects of age, gender, weight, height, and body mass index (BMI) on SSCSs were also investigated. Results: High percentile values for short segment latency changes varied from 0.4 to 0.7 ms. Ulnar nerve conductions were slower in the segments 2 cm below and above the elbow compared with the other segments. The amplitude was found not to decrease by >15% in subsequent short segments. There were no significant effects of age and gender on the SSCS parameters. Conductions over the short segments tended to be faster as BMI increased. Conclusions: Reference values should be determined separately over each 2-cm segment, and the effect of BMI should be considered when interpreting SSCSs.

Normative Data of Upper Limb Nerve Conduction in Young Population in and Around Barpeta Town, Assam

Journal of Evidence Based Medicine and Healthcare, 2015

INTRODUCTION Goal of our work was to establish the data of normal nerve conduction velocity (NCV) for the median and the ulnar nerves in normal healthy adults in Barpeta town area, Assam, India. METHODS Nerve conduction studies were performed prospectively in the upper limbs of 100 carefully screened, healthy individuals of either sex, who were between the ages of 20 and 60 years, by using a standardized technique. RESULTS: MOTOR STUDIES The median distal latency (DL) in men was 3.48 (0.26) ms, the amplitude (CMAPA) was 9.86 (1.92) mV, the conduction velocity (MNCV) was 55.94 (2.94) m/s and the F-wave (min latency) was 26.86 (2.12) minute. In the ulnar nerve, the motor DL was 2.3 (0.26) ms, the amplitude (CMAPA) was 9.97 (3.90) mV, MNCV was 62.97 (3.90) m/s and the F-Wave (min latency) was 25.98±2.41. In the sensory studies, the median nerve DL was 1.89 (0.25) ms, SNCV was 53.14±3.80 m/s and the amplitude (SNAPA) was 42.69 (20.48) μV for was. For the ulnar nerve the DL was 1.89 (0.36) ms, SNCV was 56.86 (6.23) m/s and the amplitude (SNAPA) was 40.92 (168.4) μV. CONCLUSION The normative conduction parameters of the commonly tested nerves in the upper limb were established in research laboratory of physiology department of our institute. The mean motor nerve conduction parameters for the median and the ulnar nerves correlated favorably with the existing literature data. However, for the sensory nerves, a higher value for the nerve action potential amplitude was demonstrated in this study.

Motor nerve conduction study parameters in healthy individuals: effect of limb dominance

International Journal of Research in Medical Sciences

Background: Nerve conduction study (NCS) is useful for evaluation of nerve, muscle, and/or neuromuscular function. Neurophysiologist interprets NCS with consideration of various anthropometric and technical parameters viz. age, gender, height, temperature etc. apart from the underlying pathology. Fewer studies have reported the effect of limb dominance on NCS. Moreover, the findings are controversial. Therefore, author aimed to investigate the effect of limb dominance on motor nerve conduction study parameters.Methods: This cross-sectional comparative study included sixty healthy individuals (44 right and 16 left handed) of either sex with age 18 to 30 years. The NCS parameters of median and ulnar nerves were assessed by stimulating it and recording from the muscle and skin overlying the nerve respectively using Digital Nihon Kohden machine. The obtained data were analyzed using independent sample t-test.Results: Right ulnar nerve onset latency was significantly longer in left-hande...

. ELECTROPHYSIOLOGICAL ASSESSMENT OF ULNAR NERVE IN

In the diabetic patients, diabetic neuropathy is one of the major causes of morbidity and disability. Therefore early detection of diabetic neuropathy is needed to prevent further complications. Objective: To assess ulnar nerve conduction parameters in diabetics with respect to non diabetic patients. Materials and Methods: The cross sectional study was conducted on 50 male type 2 diabetic patients and 50 healthy male volunteers who served as control. Ulnar motor nerves were chosen for the study. Conduction study was carried out on distal latency, amplitude and conduction velocity of nerves were measured by using computerized EMG/ NCV/EP Mark II and surface electrodes. Results: On comparing the electrophysiological parameters it was found that distal latency of the ulnar nerves was more in diabetics than controls with statistically significant difference. The amplitude was statisatically significant decreased in diabetics. The conduction velocities of nerves of both sides in diabetics were also found to be decreased which was statistically significant.

A reappraisal of various methods for measuring motor nerve refractory period in humans

Clinical Neurophysiology, 2005

Objective: To compare various techniques of stimulation and methods of analysis to estimate absolute (ARP) and relative (RRP) refractory periods in motor nerve trunks of humans. Methods: Double collision (DC) technique and two types of paired pulse (PP) technique, with test stimulation of supramaximal (PP supra) or submaximal (PP sub) intensity, were applied to 32 healthy subjects. The ulnar nerve was stimulated either at a single site (wrist) for the PP techniques or at two sites (wrist and elbow) for the DC technique, with various distal interstimuli intervals (ISIs). The elicited compound muscle action potentials (CMAPs) were recorded from the abductor digitorum minimi muscle. The DC technique provided estimates of minimal and maximal ARPs, whereas maximal RRP values were obtained with the PP techniques. Data were analyzed using three methods: a visual reading of the raw ISI-CMAP curves and two computer-aided analyses of the regression curve fitting the ISI-CMAP plots. Pain induced by each technique was assessed on a 0-10 visual analogue scale. A test-retest study was performed with the PP techniques in 12 subjects. Results: RP estimates varied with both the stimulation technique and the analysis method. The DC technique was more painful than the PP techniques, but provided shorter and more accurate ARP values, whereas the PP sub technique provided longer, but valid RRP values. Computer-aided methods of data analysis gave the lowest coefficients of test-retest variation. Conclusions: Compared to the PP techniques, the DC technique allowed the evaluation of the whole distribution of ARP estimates, not distorted by muscle fiber RPs. For RRP estimation, the PP sub technique can be preferred to the PP supra technique. Finally, computer-aided methods are preferable to analyze ISI-CMAP curves. Significance: The distribution of RP estimates can be easily and reliably assessed in whole motor nerve trunks of humans, providing valuable information to assess peripheral nerve excitability.

Normative data of upper limb nerve conduction in Central India

Indian journal of physiology and pharmacology

Nerve conduction study is an important tool to evaluate peripheral nerve abnormality. The primary purpose of this study was to provide normative electrophysiological data for commonly tested upper limb nerves in normal healthy adults. Nerve conduction studies were performed prospectively in upper limbs of 175 carefully screened healthy volunteers between the ages of 18 and 66 years using standardized techniques. There was no statistically significant difference found in conduction velocity and amplitude of motor median and ulnar nerves as well as sensory conduction velocity of median nerve. However, distal and F-minimum latencies of motor nerves, sensory amplitudes and conduction velocity of ulnar nerve was found to be significantly influenced by gender (P < 0.05). This study established normative conduction parameters of the commonly tested nerves of upper limb for our clinical neurophysiology laboratory in Central India. This can be of use to evaluate the patients with peripher...

Motor and Sensory Nerve Conduction : Technique , Measurements , and Anatomic Correlation 1

2010

This course is designed to highlight the basic principles of electrodiagnostic studies. It is suitable for electrodiagnostic technologists and physicians. The first lecture will explain the physiologic basis for the electrical activity of nerve and muscles cells. The various disease processes affecting the peripheral neuromuscular system will be reviewed. The second talk will be on the principles of nerve conduction studies. It will describe the proper recording and measurement techniques. The relationship between the measurements and the anatomic generators of the signals will be discussed. The last two presentations will discuss instrumentation and strategies to reduce noise and artifact. The effect of filters on the nerve conduction studies will be presented. Together, these presentations will give a review of the nerve conduction studies, and its applications to study the pathophysiology of the peripheral nervous system. Intended Audience This course is intended for Neurologists, Physiatrists, and others who practice neuromuscular, musculoskeletal, and electrodiagnostic medicine with the intent to improve the quality of medical care to patients with muscle and nerve disorders. Learning Objectives Upon conclusion of this program, participants should be able to: (1) discuss the basic anatomy and physiology of the neuromuscular system. (2) apply the motor and sensory nerve conduction study techniques to their practice. (3) identify and avoid technical pitfalls.

Nerve Conduction study in healthy individuals, a preliminary age based study

Kathmandu University Medical Journal, 2012

Background Nerve conduction study assesses peripheral nerve functions and has clinical implication. Objectives To study the effect of age on nerve conduction study variables in healthy adults. Methods Cross sectional study was done from Jan 2006 to Dec 2006 in department of Physiology, BP Koirala Institute of Health Sciences, Dharan, Nepal. The study was done in 34 (younger, n= 18, 17 to 29 years; older, n= 16, 30 to 57 years) consenting healthy adults of either sex. The compound muscle action potential and sensory nerve action potential were recorded using standard technique. Due to the non-normal distribution of data, the effect of age on nerve conduction study variables was analyzed using Mann Whitney U test. Results Younger vs. older individuals: older had lower Compound Muscle action potential amplitude (mV) in all motor nerves except radial and left ulnar nerves. Compound Muscle action potential duration (ms) was shorter in older (p<0.05) in ulnar, tibial, right median and ...