• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.345-359
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• 2002

The purpose of the study was to provide the fundamental data to instruct athletes through the analysis athletes' movement in javelin. Three athletes in the level of national representative were participated in this study. The study analyzed kinematic variables(lead foot and releasing javelin) through 3-D analysis and obtained the following results. 1. During withdrawal, it is important to maintain of running horizontal velocity. 2. It was showed that throng average height was $84{\pm}3.3%$ and javelin adequative degree, Among the athletes, $S_2$ who had the best record was released the javelin with the fast velocity, but throw the javelin with the less releasing velocity. 3. $S_2$ released after lead foot were completely landed and therefore it is no problem in a kinematic aspect. However, $S_1$ angle was too small. it caused increase of release velocity to be prevented. 4. $S_2$ showing the best result indicated shorter in duration time. Generally, the shorter duration time in release phase showed the longer release distance. Especially $S_1$ and $S_3$ showing the worse result indicated the longer duration time in preparatory phase, causing the breakup of force. Therefore to improve the record, it should be decreased the duration time in preparatory phase. 5. Compared with $S_1$ and $S_3$, $S_2$ showing the best record indicated the higher velocity in center of mass, trunk, upper arm, lower arm and hand That is the higher velocity of upper arm at release leaded the better velocity transfer from upper arm to following lower arm and hand, these action should be considered to be helpful of better record. According to the above conclusion, when the athletic leaders cauch athletes, they should focus on maintaining knee angle, upper body and hip angle in a previous stage of release and throwing angle, throwing height, throwing velocity in a release stage.

• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.259-278
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• 2002

This study divided straight success, pade success and failure with 7male golfers who have experiences more than 3 years, analyzed kinematic factors of golf swing to suggest scientifically. The conclusions were follows. 1) The wrist angle has significant difference in straight success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. 2) The body twist angle has no significant difference in straight success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. 3) The shoulder joint rotation angle has no significant difference in success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. 4) The left hip joint vertical angle has no significant difference in straight success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. 5) The hip joint rotation angle has no significant difference in straight success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. 6) The trunk angle has no significant difference in straight success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. 7 )The left knee joint angle has no significant difference in straight success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. This study divided golf swing motion of pattern change in straight success, pade success and failure and analyzed the kinematic factors by 3-dimension cinematography to improve performance. In the future, many researchers have to study kinematic analysis to improve performance in every events.

• Korean Journal of Applied Biomechanics
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• v.15 no.1
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• pp.29-44
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• 2005

The purpose of this study is to reveal the effects of two different kicks, the drop kick and the punt kick, into the kicking motion, through the kinetic comparative analysis of the kicking motion, which is conducted when one kicks a soccer goal. To grasp kinetic changing factors, which is performed by individual's each body segment, I connected kicking motions, which were analyzed by a two dimension co-ordination, into the personal computer to concrete the digits of it and smoothed by 10Hz. Using the smoothed data, I found a needed kinematical data by inputting an analytical program into the computer. The result of comparative analysis of two kicking motions can be summarized as below. 1. There was not a big difference between the time of the loading phase and the time of the swing phase, which can affect the exact impact and the angle of balls aviation direction. 2. The two kicks were not affected the timing and the velocity of the kicking leg's segment. 3. In the goal kick motion, the maximum velocity timing of the kicking leg's lower segment showed the following orders: the thigh(-0.06sec), the lower leg(-0.05sec), the foot(-0.018sec) in the drop kick, and the thigh(-0.06sec), the lower leg(-0.05sec), the foot(-0.015sec) in the punt kick. It showed that whipping motion increases the velocity of the foot at the time of impact. 4. At the time of impact, there was not a significant difference in the supporting leg's knee and ankle. When one does the punt kick, the subject spreads out his hip joint more at the time of impact. 5. When the impact performed, kicking leg's every segment was similar. Because the height of the ball is higher in the punt kick than in the drop kick, the subject has to stretch the knees more when he kicks a ball, so there is a significant affect on the angle and the distance of the ball's flying. 6. When one performs the drop kick, the stride is 0.02m shorter than the punt kick, and the ratio of height of the drop kick is 0.05 smaller than the punt kick. This difference greatly affects the center of the ball, the supporting leg's location, and the location of the center of gravity with the center of the ball at the time of impact. 7. Right before the moment of the impact, the center of gravity was located from the center of the ball, the height of the drop kick was 0.67m ratio of height was 0.37, and the height of the punt kick was 0.65m ratio of height was 0.36. The drop kick was located more to the back 0.21m ratio of height was 0.12, the punt kick was located more to the back 0.28m ratio of height was 0.16. 8. There was not a significant difference in the absolute angle of incidence and the maximum distance, but the absolute velocity of incidence showed a significant difference. This difference is caused from that whether players have the time to perform of not; the drop kick is used when the players have time to perform, and punt kick is used when the players launch a shifting attack. 9. The surface reaction force of the supporting leg had some relation with the approaching angle. Vertical reaction force (Fz) showed some differences in the two movements(p<0.05). The maximum force of the right and left surface reaction force (Fx) didn't have much differences (p<0.05), but it showed the tendency that the maximum force occurs before the peak force of the front and back surface (Fy) occurs.

• The Journal of the Korean bone and joint tumor society
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• v.14 no.2
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• pp.163-171
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• 2008

Purpose: We analyze the characteristics of soft tissue sarcomas presented with hematoma, which were misdiagnosed as simple hematoma initially and the proper management were delayed. Materials and Methods: The 7 patients with histologically proven soft tissue sarcoma with hematoma presented since February 1997 were evaluated retrospectively. Neither patient had a medical history of bleeding tendency nor anticoagulant therapy. Two of them had minor traumas. There were 2 men and 5 women. Average follow up period was 58 months. MRI findings, provided treatments and oncologic outcome were reviewed with the reference of related articles. Results: Retrospective review of initial MR images revealed deep seated intramuscular masses with focal solid enhanced nodules at the peripheral margin. The diagnoses were delayed at least 1 month in 3 of them which included 2 cases of simple hematoma evacuation without biopsy initially. After histologic diagnosis of soft tissue sarcoma, wide resections were performed in 4 cases. one patient underwent above knee amputation and the remained 2 patients were managed with wide resection followed by amputation due to local recurrence. At last follow up there were CDF and NED in 2 cases, respectively and AWD in 3 cases. Conclusion: To avoid the delay of diagnosis and treatment of soft tissue sarcomas presented with hematoma, high degree of clinical suspicion, careful analysis of MR images and early biopsy were important.

• 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 Korean bone and joint tumor society
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• v.9 no.1
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• pp.69-76
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• 2003

Purpose: This study was designed to provide the data base for the diagnosis and treatment of the foot tumor by investigation of the clinical and pathological characteristics and distribution of the foot tumor. Materials and Methods: 142 foot tumors of 141 patients were studied. All patients were diagnosed with surgical biopsy. We investigated clinical and pathological characteristics and epidemiologic distribution of the foot tumor by reviewing the medical records and imaging materials. The location of the tumors were classified with zone of Kirby et al. Results: 75 patients were female and 66 were male. The average age of the patients was 33.2 years old. Benign soft tissue tumors were the most as 68 cases, and followed by 57 benign bone tumors, 12 malignant soft tissue tumors and 5 malignant bone tumors. Ganglia were the most in benign soft tissue tumors as 36 cases, subungual exostoses in benign bone tumors as 18, squamous cell carcinomas in malignant soft tissue tumors as 7, and metastatic lung cancers in malignant bone tumors as 2. The rate of pain complaints was the highest in malignant bone tumors, the duration of symptom was longest in benign soft tissue tumors, and the size of the tumor was the biggest in malignant bone tumors. Neurological symptoms were found in only 3 benign soft tissue tumors. For the zonal distribution, zone 5 was the most in 59 cases and zone 4 was the least as 10. The most numbers of the benign bone tumors located in zone 5, of benign soft tissue tumors in zone 1, of malignant bone tumors in zone 1 and 2, and of malignant soft tissue tumors in zone 5. The methods of surgical treatment included intralesional or marginal resection, curettage with or without bone graft, toe amputation, below knee amputation and limb salvage. Conclusion: The tumors of the foot were rare and various, and mostly benign (88%), but we can do proper treatment of those tumors without excluding malignant tumors by considering the age of patients, pain, duration of symptom, size of the tumors, and zonal distribution.

• Journal of Korean Orthopaedic Sports Medicine
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• v.8 no.1
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• pp.26-32
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• 2009

Purpose: This study was performed to compare the strength of ligamentous attached sites of cadaveric distal femur and to obtain reliable biomechanical data to use in ligamentous reconstruction or augmentation. Materials and Methods: Fifteen cadaveric distal femurs were used for this study. After measuring the bone density, 5.0 mm cannulated screw (Experiment 1) or reconstructed porcine ligament (Experiment 2) was inserted into the each ligamentous attached sites of anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL) and lateral collateral ligament (LCL). In experiment 2, reconstructed porcine graft was fixed with bioabsorbable screw in ligamentous insertion sites. And we measured the maximal pullout force of each ligamentous attached sites of cadaveric distal femur. Results: Average bone mineral density was $1.205{\pm}0.137\;g/cm^2$ in experiment 1, $1.236{\pm}0.089\;g/cm^2$ in experiment 2, which showed no statistically significant differences. In experiment 1, average pull-out strength of ACL, PCL, MCL and LCL group were $519.1{\pm}111.7$ N, $638.9{\pm}144.4$ N, $169.7{\pm}56.0$ N, $225.6{\pm}61.5$ N respectively. In experiment 2, the average pull-out strength were $310.6{\pm}31.0$ N, $379.9{\pm}47.4$ N, $104.0{\pm}14.4$ N, $131.5{\pm}21.9$ N respectively. In experiment 1, there was no significant difference between ACL and PCL group and between MCL and LCL group. However, the maximal pullout strength of MCL and LCL group were significantly lower than that of ACL and PCL group (p<0.01). Experiment 2 showed the same results of experiment 1. Conclusion: Because stiffness of MCL and LCL attached sites are much lower than that of ACL and PCL attached sites, we may consider augmented fixation in ligamentous reconstructions of MCL and LCL.

• Journal of Korean Orthopaedic Sports Medicine
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• v.8 no.1
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• pp.46-50
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• 2009

Purpose: This study was designed to analyze? the chronic pain of adolescent Taekwondo athletes, to research the understanding about chronic pain of coaches and athletes, to? reduce the development of chronic pain. Materials and Methods: From March. 2006 to June 2007, 210 athletics and 12 coaches of elementary, middle and high school in Kwang-ju city were surveyed. They was evaluated by physical examination, simple radiographs and MRI. Results: In 210 athletics, 162(77.1%) athletes had chronic pain. 19(11.7%) athletes had over three regions of pain, 74(45.7%) athletes had two regions of pain, 69(42.6%) athletes had one region of pain. In 274 cases of 164 athletes, the most common region was foot and ankle(145 cases, 52.9%), followed by hand(47 cases, 17.2%) and knee(38 cases,13.9%), hip(25 cases, 9.1%), and lumbar area(19 cases, 6.9%) The chronic pain was classified by injury type. Contusion of foot was 103 cases(most common), sprain of ankles was 40cases, Contusion of hands and wrists was 28 cases, and so on. The etiologies of injury that causes the chronic pain were match injury in training that is most common, intensive exercise and match injury in competition. Conclusion: The chronic pain was common in adolescent Taekwondo athletes. The ankle and foot were the most common region of chronic pain and the match injury was the most common injury, caused the chronic pain. Although athletes had considerable mental stress about chronic pain, the treatment of chronic pain and rest were insufficient. Therefore the variable effort to prevent injury and to treatment injury must be considered importantly.

• Journal of Korean Orthopaedic Sports Medicine
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• v.9 no.1
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• pp.48-57
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• 2010

Purpose: To compare the incidence and risk factors for osteoarthritis after anterior cruciate ligament (ACL) reconstruction between two groups using bone-patellar tendon-bone (BPTB) and hamstring tendon (HT) autograft. Materials and Methods: 53 cases of ACL reconstruction using patellar tendon and 40 cases using hamstring tendon were followed up at least 8 years. Radiographic evaluation was done according to the Kellgren and Lawrence's classification. Clinical functional testing (Lysholm Knee Scores, the Tegner activity scores) and laxity testing (Lachman, pivot shift tests), and the instrumented laxity testing with $Telos^{(R)}$ were all examined in relation to the development of osteoarthritis. Results: Radiographic osteoarthritic changes were detected in 24 patients (45.3%) in BPTB group and 14 patients (35.0%) in HT group. Accompanying meniscal injury (BPTB p<0.001; HT p=0.091), intervals from the injury to reconstruction of > 12 months (BPTB p=0.037; HT p=0.021), and patient's age at reconstruction of > 25 years (BPTB p=0.003; HT p=0.048) were found to be significant independent predictors of osteoarthritis. However, no statistically significant correlations were found between the development of osteoarthritis and the clinical outcome or the radiographic stability in both groups. Conclusion: Although ACL reconstruction using BPTB or HT autograft had good clinical results at an average follow-up of 10 years, considerable incidence of radiographic osteoarthritic changes were noted. Various factors such as accompanying meniscal injury, protracted time from injury to reconstruction, more than 25 years old at the time of reconstruction were related to radiographic osteoarthritic changes.

• Pediatric Infection and Vaccine
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• v.18 no.1
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• pp.31-39
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• 2011

Purpose : This study was performed for the purpose of finding causative organisms and clinical features of septic arthritis or acute osteomyelitis in children. Methods : The study involved a retrospective review of the medical records of 63 microbiologically confirmed cases of acute pyogenic arthritis and osteomyelitis. All of the cases were brought about by community-associated infections and managed at the Seoul National University Children's Hospital or Seoul National University Bundang Hospital from June 2003 to July 2009. Results : The median age of all cases was 60 months and there were 35 males and 28 females. Major involved joints included the hip joint (15 cases), knee joint (7 cases), shoulder joint (4 cases), and elbow joint (4 cases). Also, major involved bones included the femur (20 cases), tibia (13 cases), humerus (7 cases), and radius (7 cases). Staphylococcus aureus was the most commonly identified causative organism, accounting for 49 cases (77.8%). Of the 49 isolates of S. aureus, methicillin-resistant S. aureus (MRSA) accounted for 8 cases (16.3%). Group B streptococcus spp. (GBS) and Salmonella spp. accounted for 3 cases, respectively. Nafcillin or cefazolin was often prescribed as an initial empirical antibiotic. There were 9 cases that were managed by a regimen that included vancomycin as the first choice. Fifty four cases (85.7%) recovered without any complications. Methicillin-sensitive S. aureus (MSSA), responsible for 41 cases, caused chronic complications in 3 cases. Of 8 cases caused by MRSA, 1 case showed chronic complication. There were no fatal cases. Conclusion : S. aureus remains the most common organism causing acute pyogenic arthritis and osteomyelitis of childhood acquired in the community. The high prevalence of methicillin resistance among S. aureus should be considered carefully in the selection of initial empirical antibiotics.