• Journal of the Ergonomics Society of Korea
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• v.25 no.2
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• pp.1-10
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• 2006

In spite of the rapid increase of computer use in our everyday life, not much effort is undertaken to take measures to prevent Musculoskeletal Disorders(MSDs). In this paper, we suggest a movable armrest which would lower the exposure to the MSDs, especially on the vicinity of arm. The aim of this study is to determine whether there are differences in wrist angle variations, forearm muscular loads, comfort and normal performance between the invented movable armrest and a conventional armrest when using a computer mouse. Eight experienced VDU workers performed a standardized simple task set which consists of 15 detailed tasks with each armrest. The wrist angle variations in the right arm were registered by electrogoniometer and the muscle activities in the shoulder, deltoid and two extensors in the forearm were also registered by electromyograph. The subjects rated perceived comfort while performing the tasks with each armrest. Working with the invented armrest, compared to general, gave significantly decreased wrist angle variations at most of the detailed tasks of both biaxial movements. Moreover, as the distance of targets increased, the difference of muscle activities in two different situations trend to be increasing. At the same time, in work with invented armrest, the subjects rated more comfort and they showed decreased normal performances in 8 detailed tasks which were mainly caused by macro moving time.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.465-472
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• 2022

Manual material handling is the one of the leading causes for musculoskeletal disorders (MSDs) and lower back discomfort. According to a study, construction formworkers suffer greater rates of muscular injuries and related illness due to manual activities. However, there is still a paucity of information on MSD, preventive posture issues, and corresponding solutions for construction aluminum formworkers. As a result, MSD and disregard of worker health and safety continue to exist at construction sites. Although preventive measures and strategies have been studied in previous research, we believe it is imperative to shed light on this problem through this study. This study aims to 1) implement a simple and cost-effective elevated bench to reduce MSDs, and 2) determine the rapid upper limbs assessment (RULA) and Ovako working posture analyzing system (OWAS) action catagory of workers in different postures to assess their MSD conditions and obtain an optimal position and posture using the Jack human modeling software and simulation tool. The study findings reveal a considerable reduction in MSD discomfort and which posture is acceptable in post-intervention instances.Thus results provide inexpensive and simple ergonomic interventions with favorable RULA and OWAS ratings that can be applied at construction sites. This study demonstrates workstation ergonomic intervention cases that can aid in understanding the urgency of applying existing research strategies into practice.

• Journal of the Ergonomics Society of Korea
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• v.25 no.2
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• pp.11-22
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• 2006

The muscular-skeletal disorders(MSDs) that have become a major issue recently in Korean industrial safety area are mainly caused by manual material handling task. The objective of this study is to provide scientific data for the establishment of work safety standard for Korean workers through the experiments of lifting task under various conditions, in order to prevent the muscular-skeletal disorders in the industrial work site. Eight male college students were recruited as participants. Three different lifting frequencies(1, 3, 5 lifts/min) and three twisting angles(including the sagittal plane and two asymmetric angles; i.e., 0°, 45°, 90°) for symmetric and asymmetric tasks, respectively, with three lifting range from floor to knuckle height, knuckle to shoulder, floor to shoulder height for one hour's work shift using free style lifting technique were studied. The maximum acceptable weight of load(MAWL) was determined under the different task conditions, and the oxygen consumption, heart rate, and RPE were measured or recorded while subjects were lifting their MAWLs. The results showed that: (1) The MAWLs were significantly decreased as the task frequency and task angle increased.; (2) The heart rate, oxygen consumption, RPE significantly increased with an increase in lifting frequency although maximum acceptable weight of lift decreased.; (3) The highest heart rate and oxygen consumption was recorded at the lifting range of floor to shoulder, followed by floor to knuckle and knuckle to shoulder.; (4) The RPE value showed that subjects perceived more exertion at the high frequency rate of lifting task and lifting range of floor to shoulder height. (5) The modeling for MAWL using isometric strength, task angle and lifting frequency were developed. It is expected that use of the results provided in this study may prove helpful in reducing MMH hazards, especially from lifting tasks for Korean, and can be used as a basis for pre-employment screening.

• Culinary science and hospitality research
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• v.23 no.1
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• pp.66-78
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• 2017

"Sarcopenia", sarcopenia is an old age syndrome, and used to describe the reduction of skeletal muscle. Initially, it was thought that sarcopenia was only a senile disease characterized by degeneration of muscle tissue. However, its cause is widely regarded as multifactorial, with neurological decline, hormonal changes, inflammatory pathway activation, declines in activity, chronic illness, fatty infiltration, and poor nutrition, all shown to be contributing factors. Skeletal muscle mass can be measured by a variety of methods, currently, the commonly used methods are dual-energy X-ray scanning (DXA), computer tomography (CT), magnetic resonance imaging (MRI), etc. Muscular skeletal disorders can also be assessed by measuring appendicular skeletal muscle (ASM), particularly muscle tissue content. At the same time, sarcopenia refers to skeletal muscle cell denervation, mitochondrial dysfunction, inflammation, hormone synthesis and secretion changes and a series of consequences caused by the above process and is a progressive loss of skeletal muscle syndrome, which can lead to the decrease of muscle strength, physical and functional disorders, and increase the risk of death. Sarcopenia is mainly associated with the aging process, but also related to other causes such as severe malnutrition, neurodegenerative diseases, and disuse and endocrine diseases associated with muscular dystrophy, and it is the comprehensive results of multi-factors, so it is difficult to define that sarcopenia is caused by a specific disease. With the aging problem of the population, the incidence of this disease is increasingly common, and seriously affects the quality of the life of the elderly. This paper reviews the etiology and pathogenesis of myopathy, screening methods and diagnosis, the influence of eating habits, etc, and hopes to provide reference for the diagnosis and treatment of this disease. At present, adequate nutrition and targeted exercise remain the gold standard for the therapy of sarcopenia.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.23 no.2
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• pp.111-118
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• 2012

Botulinum toxin is a potent neurotoxin that is produced by the bacterium Clostridium botulinum. The agent causes muscle paralysis by preventing the release of acetylcholine at the neuromuscular junction of striated muscle. Botulinum toxin A (Botox, AllerganInc., Irvine, California) is the most potent of seven distinct toxin subtypes that are produced by the bacterium. The toxin was initially used clinically in the treatment of strabismus caused by hypertonicity of the extraocular muscles and was sub-sequently described in the treatment of multiple disorders of muscular spasticity and dystonia. In treating patients with Botox for blepharospasm, Carruthers and Carruthers [5] noticed an improvement in glabellar rhytids. This ultimately led to the introduction and development of Botox as a mainstay in the treatment of hyperfunctional facial lines in the upper face. Since its approval by the U.S. Food and Drug Administration for the treatment of facial rhytids (2002), botulinum toxin A has expanded into wide-spread clinical use. Forehead, glabellar, and periocular rhytids are the most frequently treated facial regions. Indications for alternative uses for Botox in facial plastic and reconstructive surgery are expanding. These include a variety of well-established procedures that use Botox as an adjunctive agent to enhance results. In addition, Botox injection is finding increased usefulness as an independent modality for facial rejuvenation and rehabilitation. The agent is used beyond its role in facial rhytids as an effective agent in the management of dynamic disorders of the face and neck. Botox injection allows the physician to precisely manipulate the balance between complex and conflicting muscular interactions, thus resetting their equilibrium state and exerting a clinical effect. This article will address some of the new and unique indications on Botox injection in the face (the lower face and neck, combination with fillers). Important points in terms of its clinical relevance will be stressed, such as an understanding of functional facial anatomy, the importance of precise injections, and correct dosing all are critical to obtaining natural outcomes.

• Journal of Society of Preventive Korean Medicine
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• v.17 no.2
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• pp.29-46
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• 2013

A survey conducted on 1,103 patients or caretakers visited Korean medical clinics and hospitals between August 25, 2011 to September 30, 2011 by the Ministry of Health and Welfares and Korea Institute for Health and Social Affairs was analyzed and obtained following results: 1. For sociodemographic distribution, female(813) outnumbered male(290) patients with majority of patients ranging from 30s to 60s. Married patients(793) outnumbered unwed(150) patients and 65.0% with higher than high school education. Statistical significance was seen in gender, age, marital status, and education level but no significant difference for status of employment, income level, and types of insurance between the clinics and hospitals. (P<0.05). 45.1% had less than \2,000,000 in monthly salary and most of coverage was provided by either regional or work insurance. 2. 67.9% of the patients rated health conditions to be better than average and 32.1% listed as poor. People in good health showed tendency to visit Korean medical facilities. Musculo-skeletal conditions such as arthritis, ankle sprain, lumbago, muscular injury, and frozen shoulder were common conditions, followed by gastric disorders, common cold and herbal tonics. No significant difference was observed between the clinics and hospitals for above conditions, but significance was seen in atopic dermatitis, stroke, and sequela from traffic accidents (P<0.05). 3. Ten most common conditions addressed at Korean medical facilities were lumbago, arthritis, muscular injury, back sprain, gastric disorders, ankle sprain, common cold, herbal tonics, frozen shoulder and stroke. Major treatment modalities rendered were herbal medicine, herbal supplements, acupuncture and moxibustion, cupping, tuina, and Korean midical physical therapy. No significant difference existed between the clinics and hospitals. 4. All modalities showed at least 85% effectiveness. No statistical significant difference between the clinics and hospitals except for herbal decoction. (P=0.0452) 5. 88.3% of responses showed treatment satisfaction with significant difference between the clinics and hospitals (P=0.002). The occurrence of side effects was at 2%, mostly corning from treating digestive, skin, kidney disorders and neurological issues. No significant difference was observed between the clinics and hospitals. From the above results, the typical population visiting Korean medical facilities can be summarized as being middle aged female with relatively higher education and moderately low income. The health condition is generally good and the purpose of visit is to receive traditional treatments of acupuncture, herbal medicine, and physical therapy. Treatment efficacy and satisfaction were high with no significant differences between the clinics and hospitals.

• Journal of the Ergonomics Society of Korea
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• v.30 no.2
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• pp.297-302
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• 2011

Many WMSDs(work-related-musculoskeletal disorders) have been reported in diverse industries and have also attracted much attention in recent years. Neck-related MSD is generally known as one of common WMSDs, especially it happens to workers who are working at the automobile assembly plants and/or shipyards. The awkward posture is considered as a main cause of neck-related MSDs. A neck supporter was developed to prevent neck-related MSDs, and 10 males were recruited to evaluate the newly developed neck supporter by measuring subjective discomfort ratings of whole body, shoulder, neck and neck-muscle activities. Muscle activities from four neck muscle groups(left/right sternocleidomastoid and upper/middle trapezius) were measured while simulating an automobile assembly task. Results showed that the neck supporter help to significantly improve subjective discomfort for whole-body, shoulder as well as neck body parts. The analyses of muscular activities also showed that the activities of left/right sternocleidomastoid muscles were statistically decreased with the neck supporter in this study. The muscle activities of upper/middle trapezius in case of wearing the neck supporter were not significantly different with the muscle activities in case of no-wearing the neck supporter. Overall findings verified that the neck supporter might help to prevent neck-related MSDs based on the current study.

• Journal of Biomedical Engineering Research
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• v.17 no.3
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• pp.319-326
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• 1996

Clinical myography(EMG) is a technique for diagnosing neuromuscular disorders by analyzing the electrical signal that can be records by needle electrode during a muscular contraction. The EMG signal arises from electrical discharges that accompany the generation of force by groups of muscular fiber, and the analysis of EMG signal provides symptoms that can distinguish disorder of mLecle from disor- ders of nerve. One of the methods for analysis of EMG signal is to separate the individual discharge-the motor unit action potentials(MVAPS) - from EMG signal. But we can only observe the EMG signal that is a superimposed version of time delayed MUAPS. To obtain the information about MUAP(, i.e., position, firing number, magnitude etc), first of all, a method that can separate each MUAP from the EMG signal must be developed Although the methods for MUAP separation have been proposed by many researcherl they have required heavy computational burden. In this paper, we proposed a new method that has less computational burden and performs more reliable separation of superimposed EMG signal using wavelet filter which has multiresolution analysis as major property. As a result, we develope the separation algorithm of superimposed EMG signal which has less computational burden than any other researchers and exacutes exact separation process. The performance of this method has been discussed in the automatic resolving procedure which is neccessary to identify every firing of every motor unit from the EMG pattern.

• Physical Therapy Korea
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• v.26 no.4
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• pp.42-52
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• 2019

Background: Whole body-electromyostimulation (WB-EMS) is widely used for the rehabilitation and recovery of patients with various neuromusculoskeletal disorders. Objects: To objectively measure changes in lower extremity and abdominal muscles after sit-to-stand dynamic movement training using WB-EMS. Methods: A total of 46 healthy adults (23 experimental and 23 control subjects) performed sit-to-stand exercise; the experimental group with WB-EMS, and the control group without WB-EMS. The muscle activity of the lower extremity, and the muscle thickness of the lower extremity and abdominal muscles were measured before and after the intervention. Results: In terms of electromyographic activity, there was a significant interaction effect for the rectus femoris (RF) muscle (F=30.212, p=.000). With regards to ultrasonographic imaging, the muscle thickness of the RF muscle had a significant interaction effect at the muscle contraction ratio (F=8.071, p=.007). The deep abdominal muscles, such as the transverse abdominal (TrA) and internal oblique (IO) muscles, also showed significant interaction effects at the muscle contraction ratio (F=5.474, p=.024, F=24.151, p=.000, respectively). Conclusion: These findings suggest that WB-EMS may help to improve the muscular activity of the RF muscle, and the muscle thickness of the RF muscle and deep muscles such as the TrA and IO muscles.

• PNF and Movement
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• v.12 no.3
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• pp.189-199
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• 2014

Purpose: The objective of this case report is to examine the impact of physical therapy using the proprioceptive neuromuscular facilitation (PNF) concept for a patient with shoulder impingement syndrome. Methods: The patient is a 35-year-old female who has felt pain in the right shoulder for one month. The physical examination evaluated sensory integration, pain, joint integration and mobility, posture, reflex integration, range of motion, muscular strength, analysis of movement, and shoulder function. Comprehensive physical therapy was given to the patient, including stretching, mobilization, strengthening, posture correction, coordination improvement, daily activities, and sports exercises. The therapy was given 5 times a week for the first 5 weeks, then 3 times a week for the next 5 weeks. In all, the intervention lasted for 10 weeks. Results: The patient's senses, posture, and muscular strength all improved to a normal level. The degree of pain fell from 3/10 to 0/10 for activities taking place below shoulder height, and from 8/10 to 1/10 for activities above the head. Additionally, joint integration, motility, range of motion, and movements also improved. The disabilities of the arm, shoulder and hand (DASH) for functional evaluation improved from 27.5 to 10.3. Conclusion: Physical therapy using the PNF concept is effective in improving the body structure, function, activity, and participation of patients with motor disorders of the shoulder impingement syndrome.