• Journal of Dental Rehabilitation and Applied Science
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• v.17 no.4
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• pp.245-256
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• 2001

The purpose of this study is to analyze the mechanical stress and displacement on the jaws during the simulated bilateral clenching task on the three-dimensional finite element model of the dentated skull with unilateral molar loss. For this study, the computed tomography(G.E.8800 Quick, USA) was used to scan the total length of human skull in the frontal plane at 2.0mm intervals. The fully assembled finite element model consists of the articular disc, maxilla, mandible, teeth, periodontal ligament and cranium. The FE model was used to simulate the bilateral clenching in intercuspal position. The loading condition was the force of the masseter muscle exerted on the mandible as reported by Korioth et al. degrees of freedom of the zygomatic region where the masseter muscle is attached were fixed as restraints. In order to reflect the actual action of the muscles force, the displacement of the region was attached where the muscle is connected to the temporal bone and restraint conditions were given values identical to values at the attachment region of the masticatory muscle but with the opposite direction of the reaction from when the muscle force is acted on the mandible. Although the mandible generally has higher displacement and von Mises stress than the maxilla, its mandibular corpus on the molar-loss side has a higher stress and displacement than the molar-presence side. Because the displacement and von Mises Stress was the highest on the lateral surface of mandibular corpus with molar loss, the stress level of the condyle on the molar-loss side is greater than that of the molar-presence side, which in turn caused the symphysis of the mandible to bend. In conclusion, the unilateral posterior bite collapse with molar loss under para-functional activities such as bruxism and clenching can affect the stress concentration on the condyle and mandibular corpus. It is therefore necessary to consider the biomechanical function of dento-skeleton under masticatory force while designing the occlusal scheme of restoration on alveolar bone with the posterior collapse.

• Journal of the Korean Arthroscopy Society
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• v.4 no.2
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• pp.128-133
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• 2000

Purpose : To compare the changes of the patellar height, patellofemoral alignment and subjective symptom and to compare the effects of patellar tendon harvest after anterior cruciate ligament(ACL) reconstruction using autograft and allograft. Materials and Method : ACL reconstruction was performed on 87 patients who were followed up for minimum 1 year. The group I was 52 patients who were operated with bone-patellar tendon-bone autograft and the group II was 35 patients who were operated with bone-patellar tendon-bone allograft and achilles tendon allograft. At the time of follow-up, the authors evaluated the patellar height by Blackburne-Peel method, Merchant congruence angle, Lateral patellofemoral angle and subjective symptoms were assessed. Results : The patellar heights were significantly decreased from 0.86 preoperatively to 0.80 postoperatively in the group I and from 0.87 preoperatively to 0.83 postoperatively in the group II. There were no significant differences in the lateral patellofemoral angles between the both groups but in the Merchant congruence angle, significant differences were observed in the both groups, from$-1.43^{\circ}$ preoperatively to-$5.43^{\circ}$ postoperalively in the group I and from$-1.53^{\circ}$ preoperatively to$-3.65^{\circ}$ postoperatively in the group II. Conclusion : After ACL reconstruction, the patellofemoral alignment was changed and this kind of changes may be caused by multiple factorials such as harvest of autografts, ACL reconstruction itself, and quadriceps muscle atrophy.

• Journal of Korean Orthopaedic Sports Medicine
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• v.3 no.1
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• pp.66-72
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• 2004

Purpose: To evaluate the compensatory mechanism in vivo and develop the treatment guide by performing the comprehensive functional tests of the posterior cruciate ligament (PCL) deficient subjects. Material and Methods: 10 PCL deficient subjects and 10 healthy control group were evaluated. Performed functional tests were range of motion, posterior drawer test, Telos, 30$^{\circ}$ flexion wt-bearing view, KT-1000 arthrometer, gait analysis, EMG test and isokinetic tests. Results: Physical, KT-1000, Telos posterior tests showed significant differences, but 300 full weight bearing lateral view, muscle strength test revealed no difference between two groups. Less knee flexion at initial contact and reduced maximum valgus moment were observed in PCL deficient group. In vertical drop landing, PCL group had increased plantar flexion angle at initial contact. Conclusion: Compensatory mechanisms such as reduced unstable components and absorbing the maximal load of the joint were occurred after PCL insufficiency, which result in good clinical and functional outcomes. Further investigations would be needed to understand the functional adaptations of PCL deficient subjects.

• 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.26 no.2
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• pp.74-81
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• 2014

Purpose: The purpose of this study is to compare kinematics and kinetics on the knee joint between stair gait with unstable shoes and barefoot in healthy adult women. Methods: Seventeen healthy adult women were recruited for this study. The subjects performed stair ascent and descent with unstable shoes and barefoot. The experiment was repeated three times for each stair gait with unstable shoes and barefoot. Measurement and analysis of the movements of the knee joint were performed using a three-dimensional analysis system. Results: Statistically significant differences in the knee muscle force of semimembranosus, biceps femoris-long head, biceps femoris-short head and sartorius, patellar ligament, medial gastrocnemius, and lateral gastrocnemius were observed between unstable shoes and barefoot gait during stair ascent. Statistically significant differences in the knee muscle force of sartorius, rectus femoris, medial gastrocnemius, and lateral gastrocnemius were observed between unstable shoes and barefoot gait during stair descent. Statistically significant differences in the knee flexor moment of semitendinosus, biceps femoris-long head, biceps femoris-short head, sartorius, rectus femoris, vastus intermedialis, medial gastrocnemius, and lateral gastrocnemius were observed between unstable shoes and barefoot gait during stair ascent. Conclusion: Therefore, wearing unstable shoes during stair gait in daily life is considered to influence knee joint kinematics and kinetics due to the unstable shoes, and thus suggest the possibility that reducing the risks of pain, and knee osteoarthritis, stabilizing the knee joint caused by changes in the loading of the knee joint.

• The Journal of Korean Medicine
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• v.16 no.1 s.29
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• pp.9-20
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• 1995

I would like to state my own opinion on arthralgia syndrome(痺病) through the literatural studies. First of all, arthralgia symdrome(痺病) must be classified into six type basically, which are migratory arthralgia(痺病(行痺)), arthritis of heat type(濕痺), arthritis due to blood stasis(瘀血痺) and deficient rheumatism(虛痺), and then could be considered to try the compound names of arthralgia syndrome. These can come from according to the rise and decline of causes in wind(風), cold(寒), damp(濕), heat(熱), blood stasis(瘀血) and qi-blood(氣血). For example, it would be possible to apply the wind-dampness rheymatism(風濕痺) of damp-heat rheumatism(濕熱痺) in terminology of arthralgia syndrome(痺病). As rheumatoid arthritis(歷節風), rheumatoid arthritis like white tiger bite (白虎歷節風) and gout (痛風) not to mean the gout in western medicine have been announced a kind of arthralgia syndromes(痺病) by many doctors since Ming dynasty(明代) and proved it to be true, it is reasonabie not to try it any longer. And tingling and deficiency of sensation(廢木 不仁) is a symptome showing the decline of muscle power including mainly the abnormal sensation of skin, it would be recommended to be classified into fliaccidity syndrome(?痺). And then the names rheumatism invoiving lendon and ligament(筋痺), rheumatism involving blood vessels(脈痺), rheumatism involving muscle(肌痺), numbness of skin (皮痺) and rheumatism involving bone(骨痺), which have been used as the classification title with the season be received bad-qi(邪氣), must be classlfied to the location appearing aymptomes. Though obstruction of the liver-qi(肝痺), obstruction of the heart-qi(心痺), stagnation of the spleen-qi(脾痺), stagnation of the lung-qi(肺痺), stagnation of the kidney-qi(腎痺) and dysfunction of the bladder(胞痺) that used visceral and bladder name, that stated a kind of arthralgia syndrome(痺病), but it must be classified into a different diseases from arthragia syndrome.

• Archives of Plastic Surgery
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• v.38 no.1
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• pp.105-108
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• 2011

Purpose: An extensive knowledge of the arterial anatomy of the upper extremity and its variations is indispensable to the hand surgeon. We report a patient with anomalous radial artery, superficial course of two radial arteries, encountered during the excision of volar wrist ganglion. Methods: The patient was a 53-year-old man who had a painful mass on the left volar wrist for 1 year. Under general anesthesia, a curved incision was made around the mass. With the skin flaps retracted, the dome of the cyst was identified. Particular care was taken to identify and protect the radial artery, which was intimately attached to the wall of the ganglion. Two radial arteries completely encircled the ganglion. The pedicle was traced to the volar joint capsule, radiocarpal ligament. The joint was open and the capsular attachments were excised. Results: The patient made an uneventful recovery. There were two arterial pulsations at the volar side of the wrist joint. Compressing this site revealed that the major arterial contributor to blood supply in the hand was the ulnar artery. At angioCT, an anomaly of the radial artery was found with a duplication. The pathway of this aberrant artery was superficial to the original radial artery. It changed its course subcutaneously at the level of the tendon of the brachioradialis muscle, and crossing the wrist lateral to the original radial artery and ending in the deep palmar arch. Conclusion: Authors experienced a case of bifurcating radial artery encountered during the excision of ganglion on the volar of the wrist. Because these duplicated radial arteries make strong contributions to the thumb and index finger as well as to the deep palmar arch, when they are present there may be probably less blood supply to the hand from the ulnar artery. If the radial artery is palpated superficially on the brachioradialis muscle, it is important to remember the kind of anomaly.

• Physical Therapy Korea
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• v.26 no.3
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• pp.76-83
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• 2019

Background: The hyoid bone is the only non-jointed structure among the skeletal tissues of the head and neck region, and its movement and posture depend on the attached muscle, ligament, and fascia. The location of the hyoid bone is important for airway maintenance, vocalization, chewing, swallowing, breathing, and head and scapular position. In general, the location of the hyoid bone is measured using radiographs and 3D computed tomography, and no studies have reported on clinical measurement methods. Objects: This study was performed to suggest clinical measurement methods for lateral deviation of the hyoid bone and to evaluate their reliability. Methods: In this study, 24 healthy volunteers (12 males, 12 females) in Cheongju-si participated. Two examiners performed the center point test and lateral motion test twice each to measure the lateral displacement of the hyoid bone. The reliability of the center point test was analyzed using intra-class correlation coefficients (ICC), and the reliability of the lateral motion test was analyzed using Cohen's kappa coefficient. Results: The intra-rater reliability of the center point test was good, and the inter-rater reliability was moderate. The intra- and inter-rater reliability of the lateral motion test showed substantial reliability. Conclusion: Based on these results, the center point test and the lateral motion test can be used as an alternative methods of the measurement of lateral deviation of the hyoid bone for people who have musculoskeletal disorders of the head, neck, and scapula.

• Physical Therapy Rehabilitation Science
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• v.11 no.3
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• pp.279-284
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• 2022

Objective: This study was conducted to confirm the effect of physiotherapy on the balance and walking in dog with sciatic nerve injury and degenerative arthritis of stifle joints. Design: Single case study Methods: The dog walked abnormally for six months and was administrated in S animal hospital. The dog's right hindlimb was operated for cranial cruciate ligament repair and the dog had been taking a nonsteroidal anti-inflammatory analgesic before being refered. There was severe degenerated osteoarthritis in the right hindlimb. During stance and walking, the right hindlimb was often shown partial weight bearing. The dog's left hindlimb was shown plantigrade stance and walking. The radiograph was shown an intact calcaneal tendon in the left hindlimb. In the neurologic examination, sciatic nerve injury in the left hindlimb was confirmed. The dog was treated using muscle strengthening, proprioceptive exercise, underwater treadmill and Laser therapy two, or three times a week for 3 months. At the 10th and 17th treatment, it was evaluated through stance and gait analyzer system to measure dog's balance and walking. Results: 3 months following physiotherapy, the dog's balance was improved in center of pressure(COP). And peak vertical force(PVF), vertical impulse(VI) was increased in right hindlimb and double stance was decreased. Conclusions: Physiotherapy may have improved the prognosis in this dog with severe osteoarthritis and sciatic nerve injury. This study suggested that animal physiotherapy is a valuable way to improve balance and walking.

• PNF and Movement
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• v.21 no.3
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• pp.291-298
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• 2023

Purpose: This study aimed to suggest an effective exercise for treating anterior cruciate ligament (ACL) and hamstring injuries based on the dynamic control ratio (DCR) for the hamstring and quadriceps during eccentric hamstring exercises. Methods: Twenty-four healthy participants participated in this study. The participants performed three eccentric hamstring exercises, including the Nordic exercise, the supine leg curl, and single-leg deadlifts. During the eccentric hamstring exercises, the vastus medialis oblique (VMO), vastus lateralis (VL), biceps femoris (BF), and semitendinosus (ST) were measured using surface electromyography. Results: The DCR was significantly lower during the supine leg curl and single-leg deadlift than during the Nordic exercise (p < 0.05). The activity of the VMO and VL was significantly greater during the supine leg curl than during the Nordic exercise and the single-leg deadlift (p < 0.05). VL activity was significantly higher during the single-leg deadlift than during the Nordic exercise (p < 0.05). ST activity was significantly higher during the supine leg curl and Nordic exercise than during the single-leg deadlift (p < 0.05). BF activity was significantly higher during the supine leg curl than during the Nordic exercise and single-leg deadlift (p < 0.05). Finally, the BF showed significantly higher activity during the Nordic exercise compared to during the single-leg deadlift (p < 0.05). Conclusion: Based on the DCR ratio and quadriceps activity, the supine leg curl should be introduced early in rehabilitation for ACL injuries.