• Journal of the Korean Society of Physical Medicine
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• v.17 no.4
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• pp.1-13
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• 2022

PURPOSE: This study examined the effects of the craniovertebral angle, proprioception (joint error test), and the upper trapezius on the muscle tone when comparing cervical stabilization and scapula stabilization exercises and when two exercises were performed together. METHODS: The participants in this study agreed in advance, and this study was carried out by recruiting 27 university students in their twenties with mild frontal posture. The subjects were assigned randomly to three groups that performed cervical stabilization exercises, scapular stabilization exercises, and both cervical and scapular stabilization exercises. One-way repeated ANOVA was used to analyze the evaluation values of the 1^st, 3^rd, and 6^th weeks of exercise intervention within the group, and one-way ANOVA was used to compare the difference in the effects of exercise intervention among the three groups. RESULTS: Proprioception was significantly different in the cervical stabilization exercises (CSE) group and the cervical stabilization exercises + Scapular stabilization exercises (CSE+SSE) groups at three weeks, and there was a significant difference between the scapular stabilization exercises (SSE) group and the CSE+SSE group (p < .05). At six weeks, there was a significant difference between the CSE group and the CSE+SSE group, and there was a significant difference between the SSE group and the CSE+SSE group (p < .05). There was a significant difference between three and six weeks in the CSE group (p < .05). In the SSE group, there was a significant difference between pre and six weeks, and between three and six weeks (p < .05). In the CSE+SSE group, there was a significant difference between pre and three weeks, and between pre and six weeks (p < .05). On the other hand, there were no significant differences between CVA and muscular tone in all three groups (P > .05). CONCLUSION: In all groups, the proprioception (joint error test) showed significant improvement, and the CSE+SSE group showed greater improvement than the other groups. As a result, the appropriate combination of neck stabilization exercise and scapular stabilization exercise effectively improved proprioception in the presence of forward head posture (FHP).

• Journal of the Ergonomics Society of Korea
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• v.34 no.4
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• pp.313-326
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• 2015

Objective: The objective of this research is to quantitatively analyze muscle activities of arm and shoulder, according to direction in various types of one-handed manual material handling, based on surface electromyography. Background: Workers in industrial sites frequently carry out one-handed manual material handling using arm and shoulder muscles. Therefore, chronic load and accumulated fatigue occur to arm and shoulder muscles, which becomes a main cause of upper arm and shoulder musculoskeletal disorders. The shoulder muscles have widely range of motion, and complex interactions take place among various muscles including rotator cuff muscles. In this regard, research on interactions among should muscles, according to such various dynamic motions, is required. Method: Ten male subjects in their 20s participated in this research. This research considered upward, downward, leftward, rightward, forward and backward directions and fourteen muscles around arm and shoulder (biceps brachii and trapezius, etc.) as independent variables. The mean muscle activity was set as the dependent variable. This research extracted $4^{th}{\sim}7^{th}$ repetition signals according to ten times of repetitive muscle contraction, and analyzed the muscle activity concerned using the envelope detection technique. Results: The mean muscle activity of upward direction was analyzed highly statistically significant. The reason is that the effect of gravity works to arm and shoulder muscles. Also, it is conjectured that deformation of coracoacromial ligament was caused, and its contact pressure increased, due mainly to the shoulder flexion, and therefore load was analyzed high. Muscle activity was analyzed significantly low, according to concentric ballistic motion used in the concentric contraction phase by storing elastic energy in the eccentric contraction phase with a motion to bring the weight to the front of subject's body as to downward, leftward and backward directions. Because, elbow joint's flexion-extension motions mainly occurred, biceps brachii was analyzed high muscle activity as the prime mover. Conclusion: The information on the quantitative load of muscles can be applied to ergonomic work design for one-handed manual material handling to minimize muscle load. Application: This research has effectively identified muscle activity according to dynamic contraction by applying an envelope detection technique. The results can be used for ergonomic work design to minimize muscle load during the one-handed manual material handling, according to each direction. The research results are expected to be used for musculoskeletal disorder prevention and physiotherapy in the rehabilitation medical field, based on the muscle load of arm and shoulder in various directions.

• The Journal of Korean Physical Therapy
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• v.26 no.3
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• pp.156-162
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• 2014

Purpose: The purpose of this study was to investigate muscle activation related to postural stability depending on different head positions with whole body vibration (WBV) in standing. Methods: Eighteen healthy subjects voluntarily participated in this single-group, repeated-measures study in which the surface electromyography (EMG) data from upper trapezius, rectus abdominis, external oblique abdominis, erector spinae, gluteus maximus, rectus femoris, semitendinosus, medial gastrocnemius were collected over 3 different frequencies (0-10-20Hz) and 4 different head positions (neutral, flexion, extension, chin tuck) for each subject on WBV while standing. Results: The results of this study demonstrated that the EMG activity of all recorded muscles shows significant difference between three different frequencies and four head positions of WBV while standing (p<0.05). In the multiple comparison, significant differences could be observed for most of different frequency conditions except 0-10Hz of RA, 10-20Hz of ST. In contrast, no significant difference showed the comparison of the EMG activity depending on different head positions (p<0.05). Conclusion: These findings suggest that different head positions on WBV do not activate muscles related to postural stability. However, higher frequency on WBV is highly effective to activate whole body muscles included postural muscles regardless of different head positions.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.21 no.2
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• pp.15-24
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• 2015

Background: Many people are suffering from neck and shoulder pain due to muscle weakness, muscle fatigue, lack of exercise and accidents during exercise. In this study we compared the effects of McKenzie method and Mulligan technique method. Method: we randomly selected men(10) and women(10) and they are the 20s students of Busan material K college. We divided for McKenzie exercise group and Mulligan exercise group. McKenzie exercise and mulligan exercise applied cervical area three times a week for three weeks. We compared with pre-experiment and after 1~3 week through measuring the electromyography (EMG) change and neck range of motion (ROM). Results: The changes in the EMG at each exercise group, there was a statistically significant difference in each week. Although there was a significant difference after 1 week between the exercise group, the changes in the neck ROM at each exercise group there was no statistically significant difference. Conclusion: After experiment, EMG and neck ROM were increased in McKenzie exercise group and Mulligan exercise group. But Mulligan exercise group showed the change better than McKenzie exercise group in early stage. We suggest the Mulligan exercise method for recovering in early stage of neck ROM.

• Clinics in Shoulder and Elbow
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• v.9 no.2
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• pp.196-201
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• 2006

We report two cases of migration of K-wires from the acromioclavicular joint to the neck. A 73-year-old man complained of right shoulder pain for one month and had undergone orthopedic surgery because of acromioclavicular joint dislocation about 27 years earlier. Another 56-year-old man complained of left shoulder pain and neck pain for 5 years and had undergone orthopedic surgery because of acromioclavicular joint dislocation about 25 years earlier. In both cases, we took X-rays to look for the cause of shoulder pain and discovered broken and migrated K-wires in the neck. We removed the K-wires from the trapezius muscle and the paraspinal muscle respectively. K-wire fixation technique is simple and effective but should be followed up with X-rays periodically. In addition, we should warn patients of the possibility of migration of K-wire. And it is desirable for us to avoid using K-wire near major neurovascular structures like the sternoclavicular joint and the clavicle.

• Safety and Health at Work
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• v.11 no.1
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• pp.80-87
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• 2020

Background: Residential and commercial cleaning is a part of our daily routine to maintain sanitation around the environment. Health care of professionals involved in such cleaning activities has become a major concern all over the world. The present study investigates the risk of musculoskeletal disorders in professional cleaners involved in floor mopping tasks. Methods: A cross-sectional study was performed on 132 mopping professionals using a modified Nordic questionnaire. The Pearson correlation test was implemented to study the association of perceived pain with work experience. The muscle strain and postural risk were evaluated by means of three-channel electromyography and real-time motion capture respectively of 15 professionals during floor mopping. Results: Regarding musculoskeletal injuries, risk was reported majorly in the right hand, lower back, left wrist, right shoulder, left biceps, and right wrist of the workers. Work experience had a low negative association with MSDs in the left wrist, right wrist, right elbow, lower back, and right lower arm (p < 0.01). Surface EMG showed occurrence of higher muscle activity in upper trapezius and biceps brachii (BB) muscles of the dominant hand and flexor carpi radialis and BB muscles of the nondominant hand positioned at the upper and lower portion of the mop rod, respectively. Conclusion: Ergonomic mediations should be executed to lessen the observed risk of musculoskeletal injuries in this professional group of workers.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.4 no.1
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• pp.53-63
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• 2009

Objectives : The purpose of this study was to investigate the relation between neck pain and physical factors in female office workers. Methods : Neck pain group of 31 female subjects complained of neck and arm discomfort. Normal group of 20 female subjects had no complaints or minimal discomfort. Cervical curvature and muscle tone were assessed by whole spine x-ray, meridian-electromyography(MEMG), craniovertebral angle. Neck pain was evaluated by Neck Disability Index(NDI) and Visual Analog Scale(VAS). Results : The NDI score and contraction power of upper trapezius by MEMG had a relationship significantly. However, there was no relationship between NDI and cervical curvature. Conclusions : The results suggest that neck pain is related to muscle tone rather than physical stress and cervical curvature.

• Journal of the Korea Safety Management & Science
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• v.4 no.2
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• pp.57-70
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• 2002

Back pain is painful for people at a lower lumber(L4/L5 or L5/S1). It is experienced as a most frequent disaster 70％ of workers have suffered from back-pain. Especially, the occurrence rate of back pain for nurses is very high. Therefore, this study investigates female nurses who worked as a part of a medical cost management team, which mainly deal with the medical insurance in a general hospital at Seoul area. These nurses had different job tasks, which used computers for 50％ of their time, so it can be treated as VDT workers. As a first step of this project, a muscle fatigue was measured for these special VDT workers. First, survey for nurses was conducted to figure out what is a real problem of them. Second, to evaluate an experimental data, a medical cost management team was chosen for subjects. Areas of measurement were 3 places that were the trapezius (TR), the medial deltoid (MD), and the erector spine muscle (ES: L4/L5). These areas are most frequently used, so they were chosen for this study. Measurements were taken before work and after work. From these measurements, it was revealed that a fatigue really comes from their main VDT task excluding natural fatigue after work, so their work environment need to be corrected.

• Journal of Oral Medicine and Pain
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• v.22 no.1
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• pp.183-192
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• 1997

Pressure pain thresholds are routinely used in orofacial pain research to evaluate the response of deep orofacial tissues to mechanical stimulation. Like other psychophysical measurements, however, this technique must stimulate cutaneous tissues before stimulating deeper tissues. This study aimed at evaluating the influence of the cutaneous hypoesthesia on the pressure pain threshold in 30 healthy volunteers. PPTs were determined with electric pressure algometry over masseter, temporalis anterior, sternocleidomastoid, and trapezius muscle before and after skin hypoesthesia. A local anesthetic cream and a control cream were applied following a placebo-controlled double-blind design and PPTs were reassessed. Two examiners measured PPTs two times on each muscles, randomly. And the EMG activity of all muscles were measured to evaluate the relationship with PPTs. The collected data were processed by SAS/STAT program. The obtained results were as follows : 1. There were a tendency to increase PPTs after than before cutaneous hypoesthesia, but, there were no significant difference statistically. 2. PPTs were consistently higher in anterior temporalis than in masseter muscle. 3. In all occasions, PPTs were higher in males than in females(p<0.001). 4. A statistically significant correlation was obtained from values of intra-examiners and inter-examiners in all measured muscles. 5. A significantly positive correlation was not found between PPT and functional EMG activity.

• The Journal of the Korea Contents Association
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• v.8 no.6
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• pp.151-158
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• 2008

Poor posture of the neck and head has long been recognized as a factor contributing to the onset and perpetuation of pain in the head and neck region. This study were to evaluate the change of the neck pressure pain threshold in long term computer users. To elucidate change of the neck pressure pain threshold in long term computer users, the effect of computer using time(3, 6, 9, 12 and 15 hours) on neck pressure pain threshold were studied in 20 subjects. Neck pressure pain threshold were recorded 3, 6, 9, 12 and 15 hours group, and evaluated by pressure algometry to Trapezius muscle, Sternocleidomastoidius muscle, Suboccipitalis muscle and Temporalis muscle. Neck pressure pain threshold was significantly larger in 15 hours group(p<.05). But relation between neck pressure pain threshold in male group and female group were not significant differences(p>.05).