• 한국전문물리치료학회지
• /
• 제9권3호
• /
• pp.101-111
• /
• 2002

The purpose of this study was to determine EMG biofeedback training effect on the muscle activities in 3 unilateral facial palsy patients along with multiple baseline design across subjects. The auditory feedback about facial muscles (orbicularis oris, orbicularis oculi, frontalis) was provided with each patient during facial exercise training. Electromyographic (EMG) activity during maximal voluntary contraction and maximal compound muscle action potential (CMAP) amplitude elected by supramaximal electrical stimulation on facial nerve of facial muscles were measured pre- and post- EMG biofeedback training to evaluate motor learning. EMG activity during maximal voluntary contraction was increased after EMG biofeedback training and CMAP amplitude elected by supramaximal electrical stimulation was not changed in all subjects. The results indicate that EMG biofeedback training is useful method to improve motor learning of facial excercise training in unilateral facial palsy patients.

• 대한인간공학회지
• /
• 제26권3호
• /
• pp.27-33
• /
• 2007

The purpose of this study was to investigate influence of wrist position on the electromyographic(EMG) activities of the flexor digitorum superficialis (FDS) and extensor digitorum (ED) during drilling and pinch grip. Eighteen healthy subjects had been recruited and each subject performed two tasks (drilling and pinch grip) at three different wrist positions ($30^{\circ}$ flexion, neutral, $30^{\circ}$ extension). The EMG amplitude of each muscle was normalized to the amplitude in the maximal voluntary contraction (MVC). Repeated one-way ANOVA was used to compare the differences of EMG across wrist positions. The FDS EMG activity in both drilling and pinch grip was lowest at $30^{\circ}$ wrist extension and the highest at $30^{\circ}$ wrist flexion. The ED EMG activity was lowest when the wrist was neutral in both tasks. From the results of this study, we can conclude that the desirable wrist positions for drilling and pinch grip tasks are slightly extended or neutral position. Therefore, flexed wrist position should be avoided to reduce the excessive work load on the finger muscles during the tasks.

• 대한치과교정학회지
• /
• 제22권2호
• /
• pp.389-412
• /
• 1992

Along with form and function relationship of craniofacial growth comes a concern for the masticatory muscles with postnormal occlusion. It is the aim of this study to grope the certain differences upon the electromyographic activities of the masticatory muscles between normal occlusion and class II malocclusion during the varieties of oral functions. 26 persons of normal occlusion whose mean age were 18.9-25.6 years and another 26 persons of class II malocclusion whose mean age were 19.0-28.9 years served for this study. The electromyographic recordings processed by $Medelec^{\circledR}$ MS 25 EMG apparatus were taken from the anterior and posterior temporal, and anterior and posterior masseter muscles of both sides, and suprahyoid muscles as well. Analyses of the data toward such specific activities as mandibular rest, maximal biting, chewing gums and swallowing peanuts turned out the following summary and conclusions. 1. The maximal mean amplitude of the posterior temporalis showed significant augmentation in class II malocclusion, however the anterior temporalis, posterior masseter, and suprahyoid muscles manifested meaningful diminutions. 2. Stronger posterior temporalis and weaker anterior masseter and suprahyoid muscles were arranged in maximal biting with parameters of maximal mean amplitude. 3. The anterior temporalis of working side expressed smaller maximal mean amplitude in class II malocclusion. Significant swelling in duration were shown at anterior and posterior temporalis of working side, and posterior temporalis of balancing side in class II malocclusion, and marked reduction at anterior masseter of balancing side and posterior masseter of working side as well. The lessened latency were expressed at anterior masseter of working side, and anterior and posterior masseter of balancing side. Class II malocclusion group had significant prolongation of silent period duration. Mean silent period duration of 10.75 msec in normal occlusion and 24.37 msec in class II malocclusion were calculated. 4. Significant augmentations of maximal mean amplitude while swallowing peanuts were yielded at right anterior temporalis and posterior temporalis of both sides, however left anterior masseter and right posterior masseter showed diminution. No significant differences in duration showed at every muscle examined in class II malocclusion group.5. Weaker masseter and stronger temporalis were suggested as characteristics of class II malocclusion.

• 대한물리치료과학회지
• /
• 제19권4호
• /
• pp.41-46
• /
• 2012

Background : The purpose of this study was to investigate the electromyographic(EMG) amplitude of the gluteus medius muscle bilaterally at various hip angles and motions(flexion, extension and abduction). Methods : Thirty young with a mean(SD) age of 21.03(1.69) years performed hip motions(flexion, extension and abduction) while the surface EMG activity of the gluteus medius muscles was recorded bilaterally. Subjects were instructed to use the right lower limb during moving 3 different direction. Differences in EMG amplitudes in according with movement direction and angle were assessed by use of paired t-test analyses of variance for the right and left lower extremities. The alpha level was set at .05. Results : Gluteus medius muscle EMG activities in the both side were significantly greater for abduction at angles of 30 degrees than those for other motions at other angles. Conclusion : Hip abduction at angles of 30 degrees on the standing position may be effective in activating the gluteus medius muscle.

• The Journal of Korean Physical Therapy
• /
• 제11권1호
• /
• pp.129-136
• /
• 1999

The purpode of this study was to determine the EMG characteristies of 7 subjects with hemiplegic gait receiving therapeautic exercise after stroke. The akin electrode and gait analysis system were used. The normal gait of 6 health volunteers was analysised. The results were following. 1. Gluteus maximus, the extensor of hip joint had high level of activity compared to normal, and had two peak in late stance phase and early Swing phase. 2. Medial hamstring, the flexor of knee joint had low level of activity compared to normal, and had continuous low amplitude pattern. 3. Vastus lateralis, the extensor of knee joint had high level of activity compared to normal, and had not continuous high amplitude. From early stance phase and mid stance phase, activity had high level but after swing phase. similar to normal. 4. Gastrocnemius, plantar flexor of ankle joint had low level of activity compared to normal and had continuous low amplitude. 5. Tibialis anterior, dorsiflexor of ankle joint had similar muscle activity to normal and had continuous low amplitude.

• 한국안전학회지
• /
• 제10권4호
• /
• pp.103-108
• /
• 1995

This study was performed to investigate a relationship between a biomechanical analysis of compressive force at L5/S1 and electromyographic analysis of erector spinae muscle during lifting task. In the experiment, isometric contractions at 25, 50, 75, 100%MVC for short duration and sustained isometric contractions at 50%MVC were performed. For muscle recruitment patten and compressive force analysis, rectified EMG amplitudes analysis and computerized biomechanical analysis were used. To achieve data, angles of neck, shoulder, elbow, wrist, hip, knee, ankle and length of body segments were measured. Results shows that trends of initial EMG rectified amplitude were similar to those of biomechanical calculation value and for sustained isometric contraction at 50%MVC EMG rectified amplitude of erector spinae muscle after 40seconds was increased up to level of 75%MVC. Based on the results of this study, biomechanical analysis should be supplemented considering muscle fatigue, and it is also suggested that work-rest cycle critera and the evaluation of back-pain injuries should include muscle fatigue.

• 대한의용생체공학회:의공학회지
• /
• 제17권2호
• /
• pp.201-208
• /
• 1996

We have been studying an implant type EMG-controlled electrolarynx. First of all, we propose the sternohyoid muscle(SH) as a control source of the electrolarynx. The purpose of this study is to investigate the possibility that subjects control voluntarily the constriction of their SH, and produce the control signals of electrolarynx. For this pwnan, we carried out four experiments regarding the control of the electrolarynx. At the results, we found that subjects can control the start/stop of constriction and the amplitude of EMG of their SH. Also, we ascertained the possibility that the start/stop of contraction of SH controls OW/OFF of sound source of the electrolarynx and the amplitude of UG of SH controls the pitch frequency of the electrolarynx.

• 대한물리의학회지
• /
• 제13권2호
• /
• pp.129-135
• /
• 2018

PURPOSE: The imbalance of pretibial muscles can be a factor contributing to the development of pes planus. However, no study has yet compared the muscle activity of the tibials anterior (TA) to that of the extensor digitorum longus (EDL). The purpose of this study was to determine whether there are differences in the electromyographic (EMG) TA and EDL amplitude indexes (AIs) between normal and pes planus feet. METHODS: A total of 14 subjects with normal feet and 15 subjects with bilateral pes planus participated in this study. TA and EDL muscle activities were measured using a wireless EMG system and the angles of ankle dorsiflexion and eversion of the subtalar joint were measured using a universal goniometer during active ankle dorsiflexion in the prone position. AI was calculated as follows: $\text{amplitude_{TA}-amplitude_{EDL}/(amplitude_{TA}+amplitude_{EDL})}/2{\times}100$. RESULTS: The AIs of the TA and EDL were significantly lower in pes planus feet than in normal feet (p<.05). The angle of subtalar eversion was significantly greater in pes planus feet than in normal feet during active ankle dorsiflexon (p<.05). However, there was no significant difference in the angle of ankle dorsiflexion between normal feet and pes planus feet (p>.05). CONCLUSION: This study showed that TA muscle activation was lower in pes planus feet than in normal feet, resulting from greater eversion range of motion during active ankle dorsiflexion. We suggest that the imbalance of ankle dorsiflexors must be considered in pes planus management.

• The Journal of Korean Physical Therapy
• /
• 제13권3호
• /
• pp.777-789
• /
• 2001

The purpose of this study was to investigate the possibility of using surface electromyographic signals as a measure of muscle fatigue during the wheelchair propulsion. Subjects performed wheelchair exercise tests on a motor-driven treadmill with a constant-velocity of 1.25 m/sec. During each test, the raw EMC signals were acquired from the surface electrodes attached on the belly of five muscle groups: biceps brachii, pectoralis major. deltoid, triceps brachii, and trapezius. The median power frequency(MPF), and the root mean square(RMS) amplitude were calculated for each cyclic contraction in order to quantify muscle fatigue. During the wheelchair propulsion, the MPF decreased and the RMS increased in the trapezius and deltoid. However, the decreasing MPF and the increasing RMS also fluctuated severly during dynamic muscle contractions. Therefore, the MPF and RMS values should be estimated with well-designed methods and used with caution to quantify muscle fatigue during wheelchair propulsion.

• Annals of Clinical Neurophysiology
• /
• 제7권2호
• /
• pp.124-126
• /
• 2005

The effect of serratus anterior dysfunction is seen in the scapular winging. We report 2 cases with winging scapula clinically but do not reveal denervation potentials in needle electromyography. Surface myoelectric measurements of median frequency and root mean square values show difference in fatigability and amplitude in affected side.