• Journal of Oral Medicine and Pain
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• v.15 no.1
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• pp.37-44
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• 1991

The author has synchronously recorded average electromyographic activities of temporalis anteriors and masseter muscles and the maximum bite force on the mandibular first molar on the prferred chewing side. These activities were recorded in order to study the EMG activity pattern of the working side and the balancing side to maximum bete force and functioning state of muscle in 30 patients with TMD and in 30 healthy subjects as controls. The results were as follows : 1. The maximum bite force on the mandibular first molar on the preferred chewing side was 20.63kg in TMD patients and 53.30kg in the healthy subjects(p<0.01). The maximum bite force in TMD patients was 38.7% of the healthy subjects. 2. The average electromyographic activities of temporalis anterioris and masseter muscles on the working side and the balancing side during maximum bite force were lower in TMD patients than in the healthy subjects(p<0.01). The average electromyographic activities of each muscle in TMD patients were 61.0%-62.8% of the healthy subjects. 3. The proportionalities of average electromyographic activities of temporalis anteriors and masseter muscles on the working side and the balancing side to maximum bite force were greater in TMD patients than in the healthy subjects(p<0.01). 4. Between the working side and the balancing side, the proportionality of average electromyographic activity of temporalis anterior to maximum bite force on the working healthy subjects (p<0.01). The proportionality of average electromyographic activity of working side and the balancing side in both groups (p<0.05).

• The Journal of Korean Physical Therapy
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• v.32 no.4
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• pp.233-237
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• 2020

Purpose: This study compared the electromyographic activity of the tibialis anterior (TA) and isometric dorsiflexor strength during dorsiflexion according to the toe postures in individuals with ankle dorsiflexor weakness. Methods: Twenty subjects with ankle dorsiflexor weakness participated in this study. The electromyographic activity of the TA and isometric dorsiflexor strength during dorsiflexion between with toe flexion, extension, and neutral postures were measured using an electromyography device and a hand-held dynamometer in individuals with ankle dorsiflexor weakness. One-way repeated measured analysis of variance, and a Bonferroni post hoc test was used. The level of statistical significance was set to α=0.01. Results: The electromyographic activity of the TA was greater with toe flexion during dorsiflexion than with toe extension and neutral postures (p<0.01). The isometric dorsiflexor strength was smaller with toe flexion during dorsiflexion than with toe extension and neutral postures (p<0.01). Conclusions: In individuals with ankle dorsiflexor weakness, the dorsiflexion with toe flexion can help improve the TA electromyographic activity. The toe posture during dorsiflexion for selective TA activation should be considered, especially in individuals with ankle dorsiflexor weakness.

• The Journal of Korean Academy of Prosthodontics
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• v.40 no.6
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• pp.577-589
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• 2002

There are several variations in normal mastication. In them, unilateral mastication is chewing, predominantly on a preferred side of the dentition and hardly on e non-preferred side. Continual unilateral mastication may alter the coordination of masticatory muscles. Although they studied about these EMG of masticatory muscles, there were no information about characteristics of masticatory muscle activity in unilateral mastication. Therefore, In this study, we investigated the activity of the masseter and anterior temporal muscles during rest, clenching in maximum intercuspation and gum chewing in habitually unilateral mastication group compared with normal group and tried to know effects of continual unilateral mastication on activity of masticatory muscles. The results of this study were as follows 1. In electromyographic activity during rest, in bilateral mastication group pattern of muscle activity of right and left side was symmetrical. But, in unilateral mastication group, records of anterior part of temporal muscle was higher than that of bilateral mastication group (p<.01) and patterns of muscle activity of right and left side in both muscle were asymmetrical.(p<.05) 2. In electromyographic activity during clenching in maximum intercuspation, records of superficial part of masseter muscle were higher than anterior part of temporal muscle in both group. Muscle activity of temporal muscle in unilateral mastication group was a little higher han bilateral mastication group and asymmetry of activity pattern in temporal and masseter muscle was shown but these differences were not statistically significant. (p<.05) 3. In electromyographic activity during gum chewing, temporal muscle was activated earlier than masseter muscle and maximum bite force is derived from masseter muscle in both group. In unilateral mastication group, electromyographic activity of masseter and temporal muscle of preferred chewing side, regardless of right or left side chewing, was higher than that of bilateral mastication group and especially, difference in masseter muscle was statistically significant. (p<.01) Based on the above results, our study suggested that recording of masticatory muscle activity will be helpful in the effective diagnosis and treatment of some types of the parafunctional habits.

• Physical Therapy Korea
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• v.17 no.2
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• pp.1-9
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• 2010

To develop effective training methods for strengthening a weakened quadriceps femoris muscle in hemiplegic patients, we examined the effects of maximal isometric contraction of the nonparalyzed knee joint on the electromyographic activities of the paralytic muscle. An electromyogram (EMG) was used to record the electromyographic activities of the paralytic quadriceps femoris muscle in 27 hemiplegic patients. The maximal isometric contraction was measured for each subject to normalize the electromyographic activities. The maximal isometric extension and flexion exercises were randomly conducted when the knee joint angles of the nonparalyzed knees were $0^{\circ}$, $45^{\circ}$, and $90^{\circ}$. The patients were encouraged to maintain maximal isometric contractions in both knee joints during each measurement, and three measurements were taken. A one-minute rest interval was given between each measurement to minimize the effects of muscle fatigue. An average from the three values was taken as being the root mean square of the EMG and was recorded as being the maximal isometric contraction. The electromyographic activity obtained for each measurement was expressed as a percentage of the reference voluntary contraction, which was determined using the values obtained during the maximal isometric contraction. The results of this study are summarized as follows: First, when the knee joint angle of the nonparalyzed knee was $0^{\circ}$, the electromyographic activities of the paralytic medial aspect of rectus femoris were related to measurement by a maximal isometric flexion exercise than by an extension exercise (p<.05). Second, when the knee joint angle of the nonparalyzed knee was $90^{\circ}$, the electromyographic activities of the paralytic lateral aspect of rectus femoris were related to measurement by a maximal isometric flexion exercise than by an extension exercise (p<.05). The results show that myoelectrical activities of paralytic quardriceps were not related to measurement angles and exercise directions of the nonparalized knee joint. Studies on various indirect intervention to improve muscular strength of patients with nervous system disorders of the weakened muscle should be constantly conducted.

• Korean Journal of Applied Biomechanics
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• v.26 no.2
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• pp.183-190
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• 2016

Objective: The objective of this study is to present a scientific basis for ballet dancer training methods by analyzing the relationships between subjective assessment of the ballet movement 'Grand pas de chat' and kinematic and electromyographic factors. Method: The subjects were 14 professional dancers with 15 years of experience on average. Four cameras and a wireless electromyogram were used to examine kinematic factors, and the filmed videos were analyzed by 3 experts for subjective assessment. Results: Although no differences in kinematic factors were found between the excellent dancer group and the non-excellent dancer group divided based on the experts' assessment, some difference was found in electromyographic factors, especially in relation to the gastrocnemius muscle, rectus femoris muscle, and erector spinae muscle. A relationship between subjective assessment and kinematic and electromyographic factors was found, and factors such as right-side rectus femoris activation, time required, left-side gastrocnemius activation, and front-back displacement affected subjective assessment. Conclusion: This study showed a relationship between subjective assessment and kinematic and electromyographic factors. To receive higher scores in subjective assessment, it is necessary to extend the hang time by using the lower limb muscles. The findings of this study also indicate the necessity of weight training in order to improve dancing techniques.

• Journal of Oral Medicine and Pain
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• v.18 no.1
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• pp.55-62
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• 1993

The author has synchronously recorded the average electromyographic activities of the sternocleidomastoid muscles, the anterior temporal muacles and the masseter muscles. The marious levels of occlusal force were checked during clenching the resin plates which are made to fit each of the maxillary and the mandibular teeth. These activities were recorded in order to study the EMG activity pattern of the sternocleidomastoid muscle during the masticatory function of the jaw in 11 healthy subjects. The obtined results were as follows : 1. The electromyographic activities of the sternocleidomastoid muscles, the anterior temporal muscles and the masseter muscles were increased as the occlusal force increased, and the sternocleidomastoid muscles have a lineal correlationship with the occlusal force. 2. The sternocleidomastoid muscles and the masseter muscles showed higher EMG activity during clenching at the ventroflexed head position rather than at the extended head position. (p<0.05) However the EMG activities of the anterior temporal muscles showed no difference between the ventroflexed position and the extended position of the head. 3. The electromyographic activities of the sternocleidomastoid muscles, the anterior temporal muscles and the masseter muscles during clenching are similar at the habitual position and at the retruded condylar position. 4. The electromyographic activities of the sternocleidomastoid muscles, the anterior temporal muscles and the masseter muscles on the working side during mastication of gum and almonds are significantly higher than on the balancing side except the masseter muscles during mastication of almonds. (p<0.05, P<0.01) 5. The asymmetry of gum are lower than that during mastication of almonds. (p<0.05) The asymmetry indices of the sternocleidomastoid muscles are higher than those of the anterior temporal muscles and masseter muscles.

• Korean Journal of Veterinary Research
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• v.27 no.2
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• pp.335-337
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• 1987

This study was made to determine possibility of the electromyographic diagnosis of the experimentally induced adhesion of rumen to abdominal wall in goats. In goats with experimentally induced ruminal adhesion, the electromyograms were recorded at the abdominal wall accompanying with the ruminal motility. There were, however, no electromyographic recordings during ruminal motility in goats without ruminal adhesions. It was concluded that the electromygrams could be available for the diagnosis of the ruminal adhesion to abdomieal wall in ruminants.

• The Journal of Korean Physical Therapy
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• v.13 no.3
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• pp.829-837
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• 2001

Using Video Display Terminals(VDT) in the working environment often causes health complaints in the neck and shoulder region. This study was conducted on ten subjects, in order to investigate the change of electromyographic activities in the neck region(sternocleidomastoid muscle, upper trapezius muscle and erector muscle of cervical spine)with regards to the screen height and document holder position. A total of six different conditions of screen height and document holder position were measured during subjects performed a text-entry task for a duration of 10min. The raw EMG signal was transmuted into the root mean square(RMS). Two-way ANOVA for repeated measures was used to analyse the effects of the two factors. As a result, changing the screen height and document holder position has no effect on electromyographic activities in the neck region.

• Journal of Oral Medicine and Pain
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• v.2 no.1
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• pp.8-16
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• 1974

The author performed electromyographic analysis on edentulous patients aging 52 to 77 who have upper and lower full dentures for 3 to 7 years of duration. And the graphs were recorded in physiologic rest position, incisal occlusion, molar occlusion, left lateral excursion, right lateral excursion and mandibular projection. The results obtained are as follows : 1. 80 per cent of the patients are in unilateral mastication. 2. The shorter history of edentulous mouth reveals the more electric potency. 3. Facial deviation owing to unilateral mastication is the cause of higher electric potency to the deviated site. 4. There were no difference in electric potency between mandibular projection and incisal occlusion.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.4 no.2
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• pp.143-152
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• 2000

As muscular contraction is sustained, the Fourier spectrum of the myoelectric signal is shifted toward the lower frequency. This spectral density is associated with muscle fatigue. This paper describes a quantitative measurement method that performs the measurement of localized muscle fatigue by tracking changes of median frequency based on stationary wavelet transform. Applying to the human masseter muscle, the proposed method offers the much information for muscle fatigue, comparing with the conventional FFT-based method for muscle fatigue measurement.