• Journal of International Academy of Physical Therapy Research
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• v.11 no.2
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• pp.2071-2076
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• 2020

Background: Based on the understanding of the muscle activation relationship between the infraspinatus and posterior deltoid muscles to according to the angle of motion during external rotation on glenohumeral joint, effective shoulder joint strengthening exercise for the prevention and rehabilitation of shoulder injury due to muscle strength imbalance can be performed by achieving the ideal muscle activity ratio during exercise. Objectives: To compare and analyze the muscle activation changes and activity ratio of the infraspinatus and posterior deltoid muscles according to the glenohumeral external rotation angle. Design: Quasi-randomized trial. Methods: The study included 48 healthy male and female adults who provided informed consent for participation in the study. All the subjects performed isometric glenohumeral external rotation by setting the angle of motion to 30°, 45°, and 60° using a 5 kg resistance weight pulley. On surface electromyography, the differences in muscle activation and activity ratio between the infraspinatus and posterior deltoid muscles were investigated. Results: A significant difference in muscle activation was found in the comparison between the infraspinatus and posterior deltoid muscles according to the glenohumeral external rotation angle (P<.05). The muscle activation levels of the infraspinatus and posterior deltoid muscles were highest at the external rotation angles of 30° and 60°, respectively. The muscle activity ratio between the infraspinatus and posterior deltoid muscles also showed a significant difference (P<.05) and was highest at the shoulder external rotation angle of 30°. Conclusion: The findings of this study suggest that muscle activity is the highest at the shoulder external rotation angle of 30° in healthy individuals.

• Journal of Korean Medicine Rehabilitation
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• v.20 no.3
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• pp.37-60
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• 2010

Objectives : The purpose of this study was to investigate the relationship between masseter and cervical muscle activity and temporomandibular disorder in female office workers. Methods : Experimental group of 24 healthy subjects complained of temporomandibular joint related to computer use which lasted more than 3 months in the past year and was present in the past 7 days as well as on the day of test. Control group of 20 healthy subjects had no complaints of minimal discomfort on the day of test, and had no discomfort in the past 7 days. If they had reported discomfort in the past 12 months, it was of a short duration(<3 months) and resolved at least 3 months prior to participation. Outcomes were assessed by meridian-electromyography(MEMG), whole spin x-ray, mandibular function impairment questionnaire(MFIQ), neck disability index(NDI), visual analog scale(VAS), Beck depression inventory(BDI), stress reaction inventory(SRI) and Holmes & Rahe social readjustment rating scale(SRRS). Results : The contraction power of masseter muscle, upper trapezius, sternocleido-mastoid muscle and erector spinae by MEMG was significantly higher in the experimental group. The muscle fatigue of masseter muscle and sternodeido-mastoid muscle by MEMG was significantly higher in the experimental group. SRI was significantly higher in experimental group. There was no significant difference between two groups in the Jackson's angle, Cobb's method and cranio-cervical posture. Conclusions : The results suggest that temporomandibular disorder related mental stress but physical stress does not change cervical structure significantly.

• 한국체육학회지인문사회과학편
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• v.57 no.3
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• pp.345-356
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• 2018

Objective: The purpose of this study was to investigate the local stability of the lower extremity joints and muscle activation patterns of the lower extremity during walking between falling and non-falling group in the elderly women. Method: Forty women, heel strikers, were recruited for this study. Twenty subjects (age:72.55±5.42yrs; height:154.40±4.26cm; mass:57.40±6.21kg; preference walking speed:0.52±0.17m/s; fall frequency=1.70±1.26 times) had a history falls(fall group) within two years and Twenty subjects (71.90±2..90yrs; height:155.28±4.73cm; mass:56.70±5.241kg; preference walking speed: 0.56±0.13m/s) had no history falls(non-fall group). While they were walking on a instrumented treadmill at their preference speed for a long while, kinematic and EMG signals were obtained using 3-D motion capture and wireless EMG electrodes, respectively. Local stability of the ankle and knee joint were calculated using Lyapunov Exponent (LyE) and muscles activation and their co-contraction index were also quantified. Hypotheses were tested using one-way ANOVA and Mann-Whitey. Spearman rank was also used to determine the correlation coefficients between variables. Level of significance was set at p<.05. Results: Local stability in the knee joint adduction-abduction was significantly greater in fall group than non-fall group(p<.05). Activation of anterior tibials that acts on the foot segment dorsal flexion was greater in non-fall group than fall group(p<.05). CI between gastrocnemius and anterior tibials was found to be significantly different between two groups(p<.05). In addition, there was significant correlation between CI of the leg and LyE of the ankle joint flexion-extention in the fall group(p<.05). Conclusion: In conclusion, muscles that act on the knee joint abduction-adduction as well as gastrocnemius and anterior tibials that act on the ankle joint flexion-extention need to be strengthened to prevent from potential fall during walking.

• The Korean Journal of Pain
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• v.4 no.2
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• pp.168-178
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• 1991

It has been generally known that shoulder pains are attributed to the degenerative changes around the shoulder joint. However, many patients who complain of pain or limited range of motion of the shoulder have no definite pathology on X-ray or laboratory examinations. I examined 134 patients with shoulder pain and found the fact that compression of the axillary nerve, which leads to contraction of the deltold muscle or teres minor muscle, resulted in pain and limited range of motion in many cases. Accordingly, relieving the compression of the axillary nerve by laser stimulation or local anesthetic infiltration on the identified trigger point, anti-inflammatory medication, muscle relaxant together with ordinary physical therapy was found to be very effective in the treatment of shoulder pain.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.1
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• pp.150-157
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• 2008

Bellows are commonly used in piping systems to absorb expansion and contraction in order to reduce stress. Unlike most piping components, bellows consist of a thin-walled shell of revolution with a corrugated meridian, in order to provide the flexibility needed to absorb mechanical movements. It is a composite shell structure consisting of at least one toroidal shell, an annular plate or conical shell. It is difficult to analyze the behavior of bellows because of its complex geometry. Simplified formulas for variable mechanical behaviors of bellows are provided by a standard called EJMA. An automatic design software for bellows is programming by using VBA(Visual Basic for Application) based on EJMA. Bellows engineers can effectively make a decision for bellows geometries because this software provides graphically design results in its post-processor. Bellows design software is expected to give quite a good guidance to practical design. The characteristics of bellows are also investigated through the automatic design process in bellows design software.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.1
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• pp.176-187
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• 2001

Most bridges have expansion joints to accommodate thermal expansion and contraction without inducing large forces in the bridges. To evaluate the effects of earthquake-induced at expansion joints of concrete bridges, the first part of this paper deals with a collinear impact between concrete segments, which have the same cross section but different lengths. Especially, impact force, momentum, strain energy and kinetic energy are formulated in mathematically. These results are then used in the second part of this paper to simulate a realistic yet simple analysis of seismic pounding in concrete bridges. Analysis of seismic pounding in idealized concrete bridges is carried out by using a simple lumped-mass model and rationally determined values of the coefficient of restitution and the duration of impact.

• The Korean Journal of Pain
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• v.7 no.1
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• pp.34-38
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• 1994

The common disorder called tennis elbow exhibits typical clinical characteristics, i.e. painful condition at the lateral aspect of elbow joint on resisted wrist extension. However an exact cause for this painful condition has not yet been established. Many observers believe that the usual lesion of tennis elbow is a partial rupture of the extensor tendon at the tenoperiosteal juction on the lateral epicondyle of humerus. However the mechanism of the tendon rupture has never been explained. Conservative treatments on the tender area have been the most common therapeutic modalities for pain relief of tennis elbow. Based on my clinical experiences and anatomical studies, I discerned that tennis elbow is a periostitis of lateral epicondyle of humerus secondary to spastic contraction of muscular belly of extensor carpi radialis after over-stretched injury. Therefore, spasmolytic treatment on the extensor carpi radialis muscle provided a favorable result for permanent relief for tennis elbow pain.

• Science of Emotion and Sensibility
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• v.24 no.4
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• pp.129-138
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• 2021

This study aimed to determine the effects of the shape and attachment position of stretchable textile sensors coated with carbon nanotube on their performance when used to measure children's joint movements. Moreover, the child-safe requirements for fabric motion sensors are established. The child participants were advised to wear integrated clothing equipped with the sensors of various shapes (rectangular and boat-shaped) and attachment positions (at the knee and elbow joints or 4 cm below the joints). The voltage change induced by the elongation and contraction of the fabric sensors was determined for arm and leg flexion-extension motions at 60 deg/s (three measurements of 10 repeats each for 60°and 90°angles, for a total of 60 repetitions). Their dependability was determined by comparing the fabric motion sensors to the associated acceleration sensors. The experimental results indicate that the rectangular-shaped sensor affixed 4 cm below the joint is the most effective fabric motion sensor for measuring children's arm and leg motions. In this study, we designed a textile sensor capable of tracking children's joint motion and analyzed the sensor shape and attachment position on motion sensing clothing. We demonstrated that flexible fabric sensors integrated into garments may be used to detect the joint motions of the human body.

• Journal of Biomedical Engineering Research
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• v.33 no.2
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• pp.98-103
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• 2012

The purpose of this study was to compare premotor time(PMT) and electro-mechanical delay(EMD) between sitting and standing posture. Twenty four healthy young subjects(12 women and 12 men) participated in this study. Subjects were instructed to perform maximal, voluntary, isometric contraction of ankle muscle(tibialis anterior and gastrocnemius muscles) in reaction to auditory stimulus. PMT and EMD, calculated from stimulus, EMG and torque profile were compared between sitting and standing postures. As statistical analysis, paired t-test was performed to assess difference between sitting and standing posture. In both tibialis anterior and gastrocnemius muscles, EMD was found to be significantly longer for standing than sitting. However, PMT in standing posture was longer than that in sitting posture only in gastrocnemius muscles. These result indicate that increased reaction time, particularly, increased EMD of ankle muscles in standing posture may be caused by co-contraction of ankle muscles for postural control in standing posture.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.9 no.2
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• pp.111-117
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• 2013

Some odontogenic infections erode into fascial spaces directly and spread toward lymphatic tissues and blood streams. The principal maxillary primary spaces are the canine, buccal, and infratemporal space, the next secondary spaces are the masseteric, temporal and pharygeal space. As a result of the infection, trismus and orocutaneous fistula may be occurred. Trismus is owing to conditions not associated with temporomandibular joint itself and may be of myogenic, neurogenic, or psychogenic nature. Muscular trismus is due to infection adjacent to the elevator muscles of the jaw. The four principles of treatment of infection are as follows: (1) removal of the cause, (2) establishment of drainage, (3) institution of antibiotic therapy, and (4) provision of supportive care, including rest, nutrition and physiotherapy. Jaw physiotherapy is necessary to increase the amount of mouth opening and regain normal muscle tone. If proper care of odontogenic infection could be attained, the orocutaneous fistula will heal and close spontaneously by wound contraction mechanism of natural homeostatic response. This is a case report of the care of trismus and orocutaneous fistula due to fascial space abscess by advanced odontogenic infection in a physically disabled patient.