Kurtosis, a new variable with possible diagnostic value in analysis of jaw muscle surface EMG

Standard Values of the Amplitude of Jaw Jerk Action Potential and Differences Due to Age, Sex and L-Dopa Treatment

Journal of Dental Research ◽

10.1177/00220345790580040601 ◽

1979 ◽

Vol 58 (4) ◽

pp. 1337-1340 ◽

Cited By ~ 14

Author(s):

Sven-Erik Widmalm ◽

Harry Gill ◽

Sven Widmalm ◽

Sven Gottmar Ericsson

Keyword(s):

Action Potential ◽

Action Potentials ◽

Diagnostic Value ◽

Surface Emg ◽

Elderly Subjects ◽

Before And After ◽

Standard Values ◽

Males And Females ◽

Masticatory System ◽

Emg Electrodes

The amplitude of the jaw jerk action potential (MSP) is a parameter with possible diagnostic value. Standard values have, however, not yet been established. MSPs were recorded using surface EMG electrodes in the masseter and the anterior temporal muscles of young and elderly healthy males and females. The group means ranged from 0.26 to 2.11 mV in the masseter and from 0.17 to 0.81 mV in the anterior temporalis. The amplitude of MSP was higher in females than in males, decreased in elderly subjects and lower in the temporalis than in the masseter. The jaw jerk action potentials also were recorded in four subjects before and after L-Dopa administration. The amplitude increased by about 90%. It is concluded that the parameter MSP amplitude can be useful in the studies of muscle spindle sensitivity and the influence of various physiological, pathophysiological and pharmacological factors on the nervous regulation and muscle function in the masticatory system.

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Effect of experimental jaw-muscle pain on the spatial distribution of surface EMG activity of the human masseter muscle during tooth clenching

Journal of Oral Rehabilitation ◽

10.1111/j.1365-2842.2011.02246.x ◽

2011 ◽

Vol 39 (2) ◽

pp. 81-92 ◽

Cited By ~ 20

Author(s):

T. CASTROFLORIO ◽

D. FALLA ◽

K. WANG ◽

P. SVENSSON ◽

D. FARINA

Keyword(s):

Spatial Distribution ◽

Muscle Pain ◽

Masseter Muscle ◽

Surface Emg ◽

Emg Activity ◽

Jaw Muscle ◽

Tooth Clenching

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Trend Analysis of Jaw Jerk Action Potential-Amplitude Data

Journal of Dental Research ◽

10.1177/00220345790580040501 ◽

1979 ◽

Vol 58 (4) ◽

pp. 1333-1336 ◽

Cited By ~ 4

Author(s):

Sven-Erik Widmalm ◽

Harry Gill ◽

Sven Widmalm

Keyword(s):

Action Potential ◽

Trend Analysis ◽

Linear Trend ◽

Diagnostic Value ◽

Surface Emg ◽

Small Samples ◽

Elderly Subjects ◽

Average Value ◽

Amplitude Data ◽

Young And Elderly Subjects

The amplitude of the jaw jerk action potential (MSP) is a parameter with potential diagnostic value. It has apparently a large and irregular variation which has not yet been subjected to a thorough analysis. It is important to know if samples of MSP contain trends. The occurrence of trends indicates that the average value is influenced in a principally different way by changes in the number of observations per sample than if trends do not occur. If, for instance, there is a positive linear trend in the data, this means that the average value is larger if the number of observations is large and smaller if the number of observations is small. Samples of MSPs therefore were recorded, using surface EMG electrodes in the masseter and the anterior temporal muscles of young and elderly subjects, and subjected to trend analysis. Trends of the 14th grade occurred in 51% of the samples. Both positive and negative linear trends were found and had about the same frequency. The trend components were, however, randomly distributed. Comparisons between groups may therefore be made without the claim of trend-free samples. This significantly facilitates the use of the parameter MSP-amplitude, since it is difficult to obtain samples which have a normal and identical distribution.

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A Clinical Electroneuromyography Protocol for Localization Diagnosis of Hypotonia Syndrome in Young Children

Doctor Ru ◽

10.31550/1727-2378-2020-19-9-20-26 ◽

2020 ◽

Vol 19 (9) ◽

pp. 20-26

Author(s):

V.N. Komantsev ◽

◽

K.Yu. Mollaeva ◽

Z.R. Umakhanova ◽

◽

...

Keyword(s):

Young Children ◽

Neuromuscular Disorders ◽

Diagnostic Value ◽

Surface Emg ◽

Sensory Nerves ◽

Lower Limbs ◽

Study Objective ◽

Study Materials ◽

Study Results ◽

F Wave

Study Objective: To develop a clinical electroneuromyography (ENMG) protocol based on routine electromyography (EMG), standardization of needle EMG, and EMG parameters of the suprasegmental structures, for localization diagnosis of hypotonia syndrome (HS) in young children. Study Design: This was a comparative prospective study. Materials and Methods: One hundred and twenty-three patients, aged 1 month to 3 years, with HS of various origin underwent clinical examination and EMG. The following techniques were used for localization diagnosis by ENMG: surface EMG, needle EMG, measurement of nerve conduction velocity in peripheral motor and sensory nerves in the upper and lower limbs, F-wave measurement, and rhythmic stimulation. Study Results: The authors evaluated the possibility of describing suprasegmental disorders using the following parameters: F-wave monomorphism, myotatic reflex, and amplitude of voluntary muscular contractions. They proposed a clinical ENMG protocol for localization diagnosis of HS and a pediatric protocol for needle EMG; these approaches increased the rate of detecting HS up to 90-100%. They also developed a pediatric linear protocol for needle EMG to differentiate between myogenic and central HS. Conclusion: The study results demonstrated the high diagnostic value of ENMG-based differential diagnosis of HS, relying on the proposed protocols and on parameters indicating the condition of the suprasegmental structures. Keywords: neuromuscular disorders, hypotonia syndrome, electroneuromyography, diagnostic protocol, young children.

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Diagnostic Value of Electron Microscopy in Soft Tissue Tumors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068096 ◽

1970 ◽

Vol 28 ◽

pp. 220-221

Author(s):

Gerald Fine ◽

Azorides R. Morales

Keyword(s):

Cardiac Myxoma ◽

Osteogenic Sarcoma ◽

Diagnostic Value ◽

Soft Tissue Tumors ◽

Amelanotic Melanoma ◽

Growth Patterns ◽

Light Microscopic Level ◽

Mesenchymal Tumors ◽

Good Agreement

For years the separation of carcinoma and sarcoma and the subclassification of sarcomas has been based on the appearance of the tumor cells and their microscopic growth pattern and information derived from certain histochemical and special stains. Although this method of study has produced good agreement among pathologists in the separation of carcinoma from sarcoma, it has given less uniform results in the subclassification of sarcomas. There remain examples of neoplasms of different histogenesis, the classification of which is questionable because of similar cytologic and growth patterns at the light microscopic level; i.e. amelanotic melanoma versus carcinoma and occasionally sarcoma, sarcomas with an epithelial pattern of growth simulating carcinoma, histologically similar mesenchymal tumors of different histogenesis (histiocytoma versus rhabdomyosarcoma, lytic osteogenic sarcoma versus rhabdomyosarcoma), and myxomatous mesenchymal tumors of diverse histogenesis (myxoid rhabdo and liposarcomas, cardiac myxoma, myxoid neurofibroma, etc.)

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