• Korean Journal of Applied Biomechanics
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• v.25 no.3
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• pp.275-281
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• 2015

Objective : In order for Taekwondo athletes to perform destructive kicking performance, they are expected to have Taekwondo-specific muscle properties such as high muscle strength and power. The purpose of this study was to investigate the joint angle-dependent force-producing property of Taekwondo athletes' knee extensor muscles, which is one of the primary muscle groups involved in kicking performance. Method : Ten Taekwondo male athletes (age: $19.9{\pm}0.7yrs$, height: $180.6{\pm}6.2cm$, body mass: $75.9{\pm}8.9kg$, career: $9.2{\pm}2.9yrs$.) and 10 healthy male non-athletes (age: $26.3{\pm}2.6yrs$, height: $174.2{\pm}4.8cm$, body mass: $72.8{\pm}7.7kg$) participated in this study. Subjects performed maximum isometric knee extension at knee joint angles of $40^{\circ}$, $60^{\circ}$, $80^{\circ}$, and $100^{\circ}$ (the full knee extension was set to $0^{\circ}$) with the hip joint angles of $0^{\circ}$ and $80^{\circ}$ (the full extension was set to $0^{\circ}$). During the contractions, knee extension torque using an isokinetic dynamometer simultaneously with muscle activities of the rectus femoris (RF), and the vastus lateralis (VL) and vastus medialis (VM) using surface electromyography were recorded. Based on the torque values at systematically different knee-hip joint angles, the joint torque-angle relationships were established and then the optimal joint angle for the knee extensor was estimated. Results : The results of this study showed that the isometric knee extension torque values were greater for the Taekwondo athletes compared with the non-athlete group at all hip-knee joint angle combinations (p<.05). When the hip joint was set at $80^{\circ}$, the peak isometric torque was greater for the Taekwondo athletes compared with the non-athlete group ($313.61{\pm}36.79Nm$ and $221.43{\pm}35.92Nm$, respectively; p<.05) but the estimated optimum knee joint angles were similar ($62.33{\pm}5.71^{\circ}$ and $62.30{\pm}4.67^{\circ}$ for the Taekwondo athletes and non-athlete group, respectively). When the hip joint was set at $0^{\circ}$, the peak isometric torque was greater for the Taekwondo athletes compared with the non-athlete group ($296.29{\pm}45.13Nm$ and $199.58{\pm}25.23Nm$, respectively; p<.05) and the estimated optimum knee joint angle was larger for the Taekwondo athletes compared with the non-athlete group ($78.47{\pm}5.14^{\circ}$ and $67.54{\pm}5.77^{\circ}$, respectively; p<.05). Conclusion : The results of this study suggests that, compared with non-athletes, Taekwondo athletes have stronger knee extensor strength at all hip-knee joint angle combinations as well as longer optimum muscle length, which might be optimized for the event-specific required performance through prolonged training period.

• Korean Journal of Veterinary Research
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• v.16 no.2
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• pp.205-219
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• 1976

한국재래산양(韓國在來山羊) 12마리의 후지근(後肢筋)을 절개하여 관찰하였던 바 다음과 같은 결과를 얻었다. 1. 한국재래산양(韓國在來山羊)의 후지근(後肢筋)에서는 다음과 같은 근(筋)들을 관찰할 수 있었다 : 소요근(小腰筋) M. psoas minor, 대요근(大腰筋) M. psoas major, 장골근(腸骨筋) M. iliacus, 요방형근(腰方形筋) M. quadratus lumborum, 대퇴근막장근(大腿筋膜張筋) M. tensor fasciae lata, 중둔근(中臀筋) M. gluteus medius, 심둔근(深臀筋) M. gluteus profundus, 둔이두근(臀二頭筋) M. gluteobiceps, 반건양근(半腱樣筋) M. semitendinosus, 반막양근(半膜樣筋) M. semimbranosus, 봉공근(縫工筋) M. sartorius, 박근(薄筋) M. gracilis, 치골근(恥骨筋) M. pectineus, 내전근(內轉筋) M. adductor, 대퇴방형근(大腿方形筋) M. quadratus femoris, 외폐쇄근(外閉鎖筋) M. obturatorius externus, 내폐쇄근(內閉鎖筋) M. obturatorius internus, 쌍자근(雙子筋) M. gemelli, 대퇴사두근(大腿四頭筋) M. quadriceps femoris, 제삼비골근 M. fibularis tertius, 내측지신근(內側趾伸筋) M. extensor digitorum medialis, 장지신근(長趾伸筋) M. extensor digitorum longus, 전경골근(前脛骨筋) M. tibialis cranialis, 장비골근 M. fibularis longes, 외측지신근(外側趾伸筋) M. extensor digitorum lateralis, 비복근 M. gastrocnemius, 가제미근(筋) M. soleus, 천지굴근(淺趾屈筋) M. flexor digitorum superficialis, 심지굴근(深趾屈筋) M. flexor digitorum profundus, 슬와근(膝窩筋) M. popliteus, 골간근(骨間筋) M. interosseus medius. 2. 천둔근(淺臀筋)의 전부(前部)는 대퇴근막장근(大腿筋膜張筋)과 융합된 것 같고, 후부(後部)는 대퇴이두근(大腿二頭筋)과 융합된 것 같다. 그러나 천둔근(淺臀筋)의 후부(後部)와 대퇴이두근(大腿二頭筋)이 결합된 것으로 생각되는 부분에는 완전융합이 일어나지 않고 천둔근(淺臀筋)을 구분(區分)할 수 있을 정도로 표면으로 2근(筋)을 분리(分離)할 수 있었다. 3. 외측지신근(外側趾伸筋)과 내측지신근(內側趾伸筋)의 건(腱)은 부전골의 원위(遠位) 1/3부(部)에서 서로 건막성(腱膜性)띠에 의하여 서로 연결 되었는데, 이 건막성(腱膜性) 띠는 건섬유(腱纖維)의 방향(方向)으로 보아 외측지신근(外側趾伸筋)의 건(腱)에서 분리(分離)되어 나온 한 가지 (branch)가 내측지신근(內側趾伸筋)의 건(腱)으로 이행되고 있었다. 4, 양(羊)에서 볼 수 있는 이상근(梨狀筋) M. piriformis과 장모지신근(長母趾伸筋) M. extensor hallucis longus은 나타나지 않았다.

• Clinics in Shoulder and Elbow
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• v.24 no.4
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• pp.231-238
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• 2021

Background: Extensor muscle strengthening exercises with counterforce braces (EX) is a conventional conservative treatment for lateral epicondylitis (LE) of the elbow. In addition, polydeoxyribonucleotide (PDRN) or extracorporeal shockwave therapy (ESWT) has been recently used for LE. Methods: Sixty-three patients with chronic LE participated in this study and randomly allocated in three groups (G1: EX, G2: EX+PDRN injection, and G3: EX+ESWT). All of the three groups were taught to perform EX at the first out-patient department (OPD) visit. Group 2 was injected with 3 mL PDRN (5.625 mg/3 mL), while group 3 received ESWT at the first OPD visit. Visual analog scale pain score, Mayo elbow performance score (MEPS), and ultrasonographic examination were checked before, 6 weeks, and 12 weeks after the treatments. Results: Overall functional scores and ultrasonographic findings in all three groups improved after treatment. The mean MEPS in group 2 improved more than groups 1 and 3 at 6 weeks (G1, 56.9>62.4; G2, 54.3>65.0; G3, 55.7>62.6), and more than group 1 at 12 weeks (G1, 56.9>67.9; G2, 54.3>73.6). The mean common extensor tendon depth (CETD) on ultrasonography in group 2 increased more than groups 1 and 3 at 6 and 12 weeks (6 weeks: G1, 0.385>0.386; G2, 0.332>0.392; G3, 0.334>0.357; 12 weeks: G1, 0.385>0.409; G2, 0.332>0.438; G3, 0.334>0.405 [cm]). Conclusions: PDRN injections combined with EX exhibited a greater improvement in mean MEPS and mean CETD compared to EX only or EX combined with ESWT for LE within the 12 weeks follow-up.

• 대한족부족관절학회:학술대회논문집
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• 2008.11a
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• pp.44-44
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• 2008

• Archives of Plastic Surgery
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• v.43 no.4
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• pp.389-390
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• 2016

• The Journal of Korean Physical Therapy
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• v.26 no.3
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• pp.182-190
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• 2014

Purpose: This study aimed to determine the effects of open kinetic chain exercise (OKCE) and closed kinetic chain exercise (CKCE) using knee reposition sensing on balance, strength, and knee joint reposition sense (JPS) in chronic stroke patients. Methods: Twenty-nine hemiplegic patients participated in this study. Participants were randomly divided into 3 groups, CKCE, OKCE, and controls, with 9, 10, and 10 participants, respectively. The CKCE group completed CKCE using knee reposition sensing, whereas the OKCE group completed OKCE using knee reposition sensing. The control group completed conventional physical therapy. Results: Significant differences between the CKCE and OKCE groups were apparent for all outcomes except the functional reaching test. The CKCE group displayed significant improvements in knee JPS versus the OKCE and control groups (p<0.01). The OKCE group displayed significant improvements in knee extensor muscle strength versus the CKCE and control groups (p<0.05). The CKCE and OKCE groups displayed significantly improvements in static balance versus the control group (p<0.05). Conclusion: CKCE and OKCE improved balance, strength, and knee JPS. Additionally, CKCE might provide a more useful intervention benefit than OKCE for increasing knee JPS, a weight-bearing task. OKCE was sufficient to improve the knee extensor muscle strength.

• The Journal of Korea Robotics Society
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• v.12 no.3
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• pp.270-278
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• 2017

The electrical muscle stimulator (EMS) based human machine interface (HMI) free to mechanical constraint and muscle fatigue problems are proposed for force feedback in a virtual reality. The device was designed to provide force feedback up to 4.8 N and 2.6 N each to the thumb and forefingers. The main objective of the HMI is to make unnecessary mechanical structures to attach on the hand or fingers. It employs custom EMSs and an interface arranged in the forearm. In this work, major muscle groups such as extensor pollicis brevis (EPB), extensor indicis proprius (EIP), flexor pollicis longus (FPL) and flexor digitorum profundus (FDP) are selected for efficient force feedback and controlled individually. For this, a human muscular-skeletal analysis was performed and verified. The validity of the proposed multi-channel EMS based HMI was evaluated thorough various experiments with ten human subjects, interacting with a virtual environment.

• Clinics in Shoulder and Elbow
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• v.17 no.3
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• pp.138-144
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• 2014

Lateral epicondylitis is one of the most common causes of elbow pain and has been known to be caused by degeneration of the extensor carpi radialis brevis (ECRB). Nonoperative treatment should be tried first in all patients, because it has been deemed highly successful; however only few prospective studies suggest that symptoms frequently was completely resolved. Operative treatment is indicated for recalcitrant pain after failed conservative treatment, which involves excision of the pathologic portion of the ECRB and results in a high degree of subjective relief and functional restoration. We will review the pathology of the lateral epicondylitis and operative and nonoperative treatment of lateral epicondylitis.

• Korean Journal of Applied Biomechanics
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• v.22 no.3
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• pp.341-348
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• 2012

The purpose of this study was to compare the muscle activities of the thoracic extensor(TE) and lumbar extensor(LE) during trunk lift (TL) exercise according to exercise position. Seventeen healthy subjects with no medial history of back pain were recruited for this study. Subjects performed the TL exercise in prone, quadruped and heel-sitting positions. The activities of the TE and LE were measured using surface electromyography during TL exercise in each exercise position. A one-way repeated-measures analysis of variance (ANOVA) was used to compare the normalized muscle activities of the TE and LE and the TE/LE ratio. The results showed that there was not significant effect of exercise position on the muscle activities of TE(p>.05). However, there was significant effect of exercise position on the muscle activities of LE and the TE/LE ratio(p>.05). Post hoc pair-wise comparisons with Bonferroni correction showed that both muscle activities of LE and TE/LE ratio in prone position were significantly different in those in heel-sitting and quadruped positions, during TL exercise, respectively. The TE/LE ratio was the greatest for TL exercise in heel-sitting position. Therefore, for selective activation of the TE muscle, we recommend performing the TL exercise in heel-sitting or quadruped position.

• Clinics in Shoulder and Elbow
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• v.7 no.1
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• pp.35-40
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• 2004

Purpose: The aim of this study was to investigate effects of calcific lesion on shockwave therapy of the tennis elbow. Materials and Methods: twenty-four patients with refractory tennis elbow were treated with shock waves. The patients were evaluated by assessment of pain using visual analog scale (VAS) and simple elbow test (SET). Comparision of clinical outcomes for the patients with and without calcification in the extensor tendon and/or cortical irregularity of lateral condyle was tried to determine if this could be a possible prognostic factor in clinical settings. Overall clinical outcomes were evaluated by Roles and Maudsley score at 12 months after ESWT. Results: Significant improvement of symptoms were observed in 20 (83 %) patients at 12 months follow up according to Roles and Maudesley scores. The patients with calcification and/or cortical irregularity improved significantly better, when compared to the patients without calcification and/or cortical irregularity at follow up. Conclusion: This study suggests that shock waves therapy could be considered as effective and noninvasive treatment modality for refractory tennis elbow. Also calcific deposit in extensor tendon and/or cortical irregularity of the lateral epicondyle was seem to be good prognostic factor for shock wave therapy for tennis elbow