• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1998.05a
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• pp.307-312
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• 1998

In forklift operations, awkward postures due to backward driving may put drivers to the risk of CTD or low back pain. In this research, 6 forklift drivers were surveyed with OWAS for objective posture evaluation and bodymaps for self-report evaluation. The backward driving happened more frequently than forward driving as expected, and, as work hours passed by, the drivers naturally tended to assume the easier work postures in inverse proportion to the frequency of the backward operations. According to the results of OWAS, 60 % of the work postures in the forklift operations belonged to the category II, III, and IV classified serious. Especially, in the backward driving, the postures with the neck twisted over $45^{\circ}$ occupied 82.4 %. In addition, discomfort on the neck, left shoulder, and low back was frequently reported in the self-reports.

• Journal of the Korea Safety Management & Science
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• v.8 no.4
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• pp.13-23
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• 2006

Grip strength provides a quick and objective index of the functional integrity of the upper extremities. It is widely used as an assessment measure in physical and rehabilitation medicine. In this study, maximum voluntary grip strength of 20 college students wearing 5 different gloves were measured using Jamar hand dynamometer. The results show that maximum voluntary grip strength was generally reduced when wearing gloves as compared to bare-handed. More specifically, the grip strength was highest when wearing PVC coated glove or bare-handed and getting lowered as wrist band, rubber, leather, and cotton glove in these order. Depending on the measuring posture of grip strength, shoulder height with arm extended forward was higher than the elbow was flexed 90 degree. Moreover, subjects' demographic factors and hand dimensions were not closely related to the grip strength. It is thus recommended that the proper glove should be provided to reduce the negative consequences including dropping a tool, poorer control of a tool. lower quality work, and increased muscle fatigue and in turn to increase the user safety and satisfaction.

• PNF and Movement
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• v.17 no.1
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• pp.41-46
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• 2019

Purpose: Continuous use of a smartphone increases the angle of forward bending of the user's cervical vertebrae, causing pain in the shoulders and back, including the thorax, lumbar region, and vertebrae. Although there are many studies on changes in the cervical spine due to smartphone usage, the changes in the shoulders, thoracolumbar spine, and pelvic have rarely been compared. The purpose of this study is to investigate the change in the spinal segments, shoulders, and pelvic when using a smartphone with both hands while in the standing position. Methods: This study was conducted on 35 adults in their twenties. The selection criteria for the subjects were limited to those in a similar age group, thus excluding posture differences according to age, and to those who did not have specific diseases or pain in the spinal and musculoskeletal system for 12 months prior to the study. In this study, we used a 3D spinal diagnostic imaging system (Back Mapper, Frickenhausen) to compare the changing conditions in each vertebral segment before and during smartphone usage with both hands while in the standing position. Posture differences according to smartphone usage were compared using the paired t-test for the motion of each spinal segment. Results: This study showed that the thoracic and lumbar angle increased posteriorly during smartphone usage (p<0.05). In addition, the anterior rotation angle of the shoulder bone significantly increased, but no significant difference occurred in the pelvic region. Conclusion: Based on the results of this study, smartphone usage with both hands while in the standing position showed that the spine, as a whole, forms a kyphotic curve. Therefore, we propose to present a postural guideline for correct smartphone usage, considering the change in each vertebral segment.

• The Journal of Korean Physical Therapy
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• v.17 no.4
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• pp.505-517
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• 2005

The Purposes of this study were to find complementary connectible new factors that analyzed correlation relate of Sasang Constitution and GCM Body Type in Static Posture and Dynamic Hyper/Hypo-mobility Pattern. Method of this study was asymtomatic volunteers 232(unmarried man and women), conducted from September 1 to December 31. In this main study progressing step diagnosised first, Constitution of Sasang medicine after being classified into four groups of Soyangin, Taeumin, Soeumin, Taeyangin diagnosis of GCM Body Type and progressed that related Static Posture and Dynamic Hyper/Hypo mobility Pattern. The results are as follows. Distribution of Sasang Medicine Constitution proved to be Taeyangin 13, Soyangin 66, Taeumin 67, Soeumin 86 respectively. Distribution of GCM Body Type proved I Body Type 72(31.0%), II Body Type 54(23.3%), III Body Type 89(38.4%), IV Body Type 17(7.3%). The distribution of Sasang Constitution according to GCM Body Type was that; I Body Type was distributed in the order Soeumin 34.7%(25), Taeumin 31.9%(23), Soyangin 30.6%(22), Soeumin 34.7%(25) is the most people. II Body Type was distribution of in the order Soeumin 42.6%(23), Soyangin 5.9%(14), Taeumin 24.1%(13), Soeumin 42.6%(23) is the most people. III Body Type was distribution of in the order Soeumin 37.1%(33), Taeumin 30.3%(27), Soyangin 28.1%(25), Soeumin 37.1% is the most people. IV Body Type proved high distribution each of Soeumin 29.4%(5) and Soyangin 29.4%(5). In case of main left side posture character of spine and limbs about I Body Type 72 persons with left scapular and ilium forward tilted pattern proved in the order high distribution iliac crest thigh and scapular high 70(97.2%), gluteal fold high and scapular abduction 69(95.8%), lumbar scoliosis 65(90.3%). Also, in case of right side posture character proved in the order high distribution deep gluteal fold 69(95.8%), umbilical deviation 68(94.4%). Incase of main left side posture character of spine and limbs about n Body Type 54 persons proved in the: order high distribution knee hyperextension 50(92.6%), shoulder deviation 49(90.7%) etc. Also, in case of right side posture character proved in the order high distribution pelvic deviation 53(98.1%), iliac crest thigh 52(96.3%), hip flexion and ankle inversion 51(94.4%) etc. In case of main left side posture character of spine and limbs about III Body Type 89 persons proved in the order high distribution shoulder deviation 87(97.8%), scapular abduction 86(96.6%), scapular high 85(95.5%) etc. And in case of right side posture character proved in the order high distribution pelvic deviation and iliac crest thigh 86(96.6%) etc. In case of main left side posture character of spine and limbs about IV Body Type 17 persons proved in the order high distribution pelvic deviation, lumbar sciliosis and lumbar lordosis increase 15(88.2%) etc. Also, in case of right side posture character proved in the order high distribution wrist dorsiflexion 16(94.1%), thickened achilles tendon etc.

• The Journal of the Korea Contents Association
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• v.10 no.6
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• pp.323-328
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• 2010

If a patient wearing arm sliding due to shoulder dislocation or fracture is impossible with abduction, the velpeau view is performed instead of superior-inferior axial projection view. However, it aggravates the patient's pain because it is difficult for the patient with dislocation or fracture to pull back the shoulders. Therefore, I suggest a new method of the 'modified velpeau view' that allows patients to lower their heads at examination. In order to investigate the easiness of fixing posture at examination and clinical utility, I conducted a study comparing the bone structures at the velpeau view and those at the modified velpeau view depending on wall-bucky and the patients' leaning forward angle ($30^{\circ},\;45^{\circ},\;60^{\circ}\;and\;75^{\circ}$), with the subjects of 20 velpeau view-prescribed patients amongst who had come to my hospital suspected of dislocation of shoulder or fracture and 30 healthy people from October of 2009 to January of 2010. Department of radiologists and orthopedics specialists evaluated the pictures for scales 0 to 5(best grade) under the given criteria. As a result of comparison in bone structures depending on wall-bucky and the leaning-forward angle in the group of healthy people, the velpeau view and the modified velpeau showed a similar diagnostic utility at $45^{\circ}$ and $60^{\circ}$. The picture evaluation result for proving diagnostic value showed that the anterior and posterior of shoulder heads and the anterior and posterior of glenoid fossa could be observed in the velpeau view; on the other hand, besides these areas acromioclavicular joint and coracoid process could be viewed in the modified velpeau view. This result verified that the modified velpeau view could replace the velpeau view for its diagnostic value as an examination method. This result, moreover, suggests that the modified velpeau view needs to be studied and improved from a variety of perspectives not only for an alternative for patients having troubles with the velpeau view position but also for clinical application of new test method for diagnosis of shoulder disorders other than dislocation of shoulder or fracture.

• Journal of the Ergonomics Society of Korea
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• v.29 no.6
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• pp.831-841
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• 2010

Usability evaluation of physical products involves characterizing complex physical interactions between humans and products. Human models known as manikins have been widely utilized as usability evaluation tools for automobile interior package design. When combined with computer-aided design software programs, such manikins can be used to simulate driving postures and evaluate driver-interior fits early in the design process, and therefore, may greatly facilitate achieving high-quality design in a cost-efficient manner. The purpose of this study was to define a set of manikins for designing automobile interior packages for the South Korean male population. These manikins were conceptualized as "boundary" manikins, which represent individuals lacking in certain physical capacities or having usability-related issues (e.g., an individual with the 5th percentile forward reach capability, an individual with the 95th percentile shoulder width). Such boundary manikins can serve as an efficient tool for determining if an automobile interior design accommodates the majority of the population. The boundary manikins were selected from the large sample of Korean males whose anthropometric dimensions were described in the recent Size Korea anthropometric database. For each male in the database, his comfortable driving posture was represented using a kinematic body linkage model and various physical capacity measured and usability-related characteristics relevant to driver accommodation were evaluated. For each such measure, a boundary manikin was selected among the Korean males. The manikins defined in this study are expected to serve as tools for ergonomic design of automobile interior packages. The manikin selection method developed in this study was implemented as a generic software program useful for various product design applications.

• Safety and Health at Work
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• v.8 no.4
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• pp.356-363
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• 2017

Background: The aim of this study was to investigate which physical and psychosocial work demands were associated with excellent work ability in individuals with neck pain, and to investigate age and sex differences in these associations. Methods: The study sample was obtained from the Statistics Sweden cross-sectional Work Environment survey and consisted of workers who reported neck pain after work (N = 3,212). Results: The findings showed an association between excellent work ability and self-reported low exposure to lifting, twisted work posture, working with hands in shoulder level or higher, and leaning forward without support and combination of exposures containing these work demands. Low exposure to seated work and high demands showed a reversed association. The associations were present mainly among older workers and were generally stronger for men than for women. Conclusion: This study indicates that a lower level of physically demanding work is an important element to maintain excellent work ability, especially for the older worker with neck pain.

• Korean Journal of Applied Biomechanics
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• v.26 no.4
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• pp.369-375
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• 2016

Objective: The purpose of this study was to investigate the possibility of injuries and the types of movement related to damage by body parts, and to prepare for prevention of injuries and development of a training program. Method: For this study, the experiment was conducted according to levels of 60 percentages (ST) and 85 percentages (MA) and 10 subjects from the Korean elite national weightlifting team were included. Furthermore, we analyzed joint moment and muscle activation pattern with three-dimensional video analysis. Ground reaction force and EMG analyses were performed to measure the factors related to injuries and motion. Results: Knee reinjuries such as anterior cruciate ligament damage caused by deterioration of the control ability for the forward movement function of the tibia based on the movement of the biceps femoris when the rectus femoris is activated with the powerful last-pull movement. In particular, athletes with previous or current injuries should perceive a careful contiguity of the ratio of the biceps femoris to the rectus femoris. This shows that athletes can exert five times greater force than the injury threshold in contrast to the inversion moment of the ankle, which is actively performed for a powerful last pull motion and is positively considered in terms of intentional motion. It is activated by excessive adduction and internal rotation moment to avoid excessive abduction and external rotation of the knee at lockout motion. It is an injury risk to muscles and ligaments, causing large adduction moment and internal rotation moment at the knee. Adduction moment in the elbow joint increased to higher than the injury threshold at ST (60% level) in the lockout phase. Hence, all athletes are indicated to be at a high risk of injury of the elbow adductor muscle. Lockout motion is similar to the "high five" posture, and repetitive training in this motion increases the likelihood of injuries because of occurrence of strong internal rotation and adduction of the shoulder. Training volume of lockout motion has to be considered when developing a training program. Conclusion: The important factors related to injury at snatch include B/R rate, muscles to activate the adduction moment and internal rotation moment at the elbow joint in the lockout phase, and muscles to activate the internal rotation moment at the shoulder joint in the lockout phase.

• The Journal of Korean Physical Therapy
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• v.33 no.4
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• pp.179-186
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• 2021

Background: Patients with advanced asthma and chronic obstructive pulmonary disease (COPD) have postural deviations such as thoracic hyperkyphosis, forward shoulder posture (FSP) due to an increase in head and cervical protraction, reduced shoulder range of motion and a corresponding increase in scapula elevation and upward rotation. Unlike congenital vertebral kyphosis that are permanent and rigid deformities with bony and other structural deformations which cause respiratory impairment, these deformities in these patients may be more flexible. Since the thoracic hyperkyphosis has been implicated as having adverse health consequences it is necessary to evaluated the relationship between thoracic kyphosis and cardiopulmonary functions of patients with COPD and asthma. Methods: It was a cross-sectional analytical study. Eighty-four eligible patients with COPD and asthma were recruited from the Respiratory Unit, Department of Medicine, Lagos University Teaching Hospital (LUTH), and basic anthropometric parameters, pulmonary parameters, cardiovascular parameters, thoracic kyphosis (Cobb) angle and presence of respiratory symptoms of participants were assessed. Data was analyzed using SPSS version 20. Results: There was no significant correlation between the thoracic kyphosis and selected pulmonary parameters (Forced Expiratory Volume in one second (FEV1, p=0.36), Forced Vital Capacity (FVC, p=0.95), Peak Expiratory Flow Rate (PEFR, p=0.16), Thoracic expansion (TE, p=0.27)/cardiovascular parameters (Systolic Blood Pressure (SBP, p=0.108), Diastolic Blood Pressure (DBP, p=0.17) and Pulse Rate (PR, p=0.93) as well as the respiratory symptoms (SGRQ scores, p=0.11) in all subjects. Conclusion: There was no relationship between thoracic kyphosis and selected pulmonary/cardiovascular parameters as well as respiratory symptoms in patients with COPD and asthma.

• Physical Therapy Korea
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• v.27 no.1
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• pp.1-10
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• 2020

Background: Thoracic spine self-mobilization exercise is commonly used to manage patients with neck pain. However, no previous studies have investigated the effects of thoracic spine self-mobilization exercise alone in patients with chronic neck pain. Objects: The purpose of this study was to investigate the effects of thoracic self-mobilization using a tool on cervical range of motion (ROM), disability level, upper body posture, pain and fear-avoidance beliefs questionnaire (FABQ) in patients with chronic neck pain. Methods: The subjects were 49 patients (21 males, 28 females) with chronic neck pain. The subjects were randomly divided into an experimental group (EG, n = 23) and control group (CG, n = 26). For the EG, thoracic self-mobilization was applied. We placed a tool (made with 2 tennis balls) under 3 different vertebral levels (T1-4, T5-8, T9-12) of the thoracic spine and the subjects performed crunches, which included thoracic flexion and extension in supine position. Five times × 3 sets for each levels, twice a week, for 4 weeks. Cervical pain, disability, upper body posture, FABQ results, and ROM were evaluated at baseline, after 4 weeks of intervention, and at 8 weeks of follow-up. Assessments included the quadruple visual analogue scale (QVAS); Northwick Park neck pain questionnaire (NPQ); craniovertebral angles (CVA), forward shoulder angle (FSA) and kyphosis angle (KA) measurements for upper body posture; FABQ and cervical ROM testing. Results: The EG showed a statistically significant improvement after intervention in the QVAS (-51.16%); NPQ (-53.46%); flexion (20.95%), extension (25.32%), left rotation (14.04%), and right rotation (25.32%) in the ROM of the cervical joint; KA (-7.14%); CVA (9.82%); and FSA (-4.12%). Conclusion: These results suggest that, for patients with chronic neck pain, thoracic self-mobilization exercise using a tool (tennis balls) is effective to improve neck pain, disability level, the ROM, and upper body posture.