• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.2
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• pp.103-111
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• 2015

The present study investigated the influence of thick cortical endplates on the ultrasonic properties of trabecular bone in a femur with a high fracture risk. Twelve trabecular bone samples were prepared from bovine femurs, and acrylic plates with thicknesses of 1.25, 1.80, and 2.75 mm were manufactured to simulate the cortical endplates using acrylic with a density and a sound speed similar to cortical bone. Although the thickness of the acrylic plates attached to the two sides of the trabecular bone increased, high correlations were observed between the speed of sound and the apparent bone density of the trabecular bone, with Pearson's correlation coefficients of 0.80-0.86. High correlations were also observed between the attenuation coefficient at 0.5 MHz and the apparent bone density of the trabecular bone, with Pearson's correlation coefficients of 0.84-0.91. These results suggest that the speed of sound and attenuation coefficient at a specific frequency measured in a femur with relatively thick cortical endplates compared to the calcaneus could be used as indices for predicting the bone mineral density of the femur.

• Journal of the Korean Arthroscopy Society
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• v.7 no.1
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• pp.92-95
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• 2003

A 34-year-old man with ACL total rupture due to slip down injury, had received ACL reconstruction using autogenous hamstrings tendon with cross-pin femoral fixation. Postoperative course was as usual. But postoperative 3 months later, he complained posterolateral knee pain, recurrent effusion and mild instability. He was managed repeatitive aspiration and nonsteroid antiinflammatory drugs but was failed to relieve symptoms & signs. In CT scans, perforation of posteromedial femoral cortex of lateral femoral condyle was found. In second look arthroscopy, two pieces of broken femoral cross pin were found in between tibiofemoral Joint which was badly injured cartilage. We considered malposition of pins was the main cause of failure. We propose that femoral tunnel must be made more acute angle and femoral cross-pin guide must be positioned more external rotation 10-20 degree than transepicondylar axis made confirm the cross-pin tunnel position in order to avoid posterior cortex perforation and early failure.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1590-1598
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• 2014

Based on an analysis on the difference on the measurement sites and their relations to osteoporosis diagnosis and prevalence, this study attempts to investigate the patterns of prevalence in skeletal sites in the aging process. The samples were driven by the National Health and Nutrition Examination Survey (2008-2010) on Korean females (n = 4,449) aged from 50 to 89 years. The result shows that the differences on affected sites in the aging process were detected as follow: the osteoporosis prevalence in lumbar spine was relatively high in 50s, 60s and 70s; however, the prevalence in the proximal femur (total hip and femoral neck) was higher in 80s. In terms of the diagnosis identified in a single site, the prevalence in lumbar spine seemed to decrease as age increases; but, the rate went up in the figure of femoral neck. Overall, the osteoporosis prevalence for the diagnosis detected in multiple sites was increased as age goes up. In general, the increase in lumbar osteoporosis prevalence starts earlier than that of femoral neck. The findings of this study also suggests that if the proximal femur site is only used for diagnosing women age in 50s, 60s and 70s, the significant portion of osteoporosis patients could be misdiagnosed as normal.

• Korean Journal of Applied Biomechanics
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• v.19 no.3
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• pp.603-610
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• 2009

The purpose of this study was to determine how spandex pants affect impact force and muscle activities in the lower extremity. Seven pairs of surface electrodes were attached to the right-hand side of the body. Paired t-test was performed to test if significant difference exist between two conditions(p< .05). The average IEMG activities in the TA, BF, and GM during the landing phase reduced significantly with spandex pants compared to regular pants. All peak IEMG activities except the RF in wearing spandex pants group were significantly greater than the corresponding values in wearing regular pants one. The greater muscle activity recorded in wearing spandex pants can be attributed to the greater motor unit recruitment needed to decelerate and stabilized their bodies. Impact force and loading rate were not significantly decreased with wearing spandex pants. Since the spandex pants used in this study were not custom-fit based on girth of each participants thigh and shank, compression and elasticity for the pants could not be optimized.

• The Journal of the Korean bone and joint tumor society
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• v.13 no.2
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• pp.135-141
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• 2007

Nodular faciitis is generally considered to be benign proliferation of fibroblasts and myoblasts, and it measures dimension up to 3cm. The characteristics such as rapid growth, abundant cellularity, and mitotic activity occasionally cause these lesions to mimic sarcoma. The authors experienced two cases of nodular fasciitis of the thigh, which were unusually large with dimension of more than 5cm. All of these two cases mimicked sarcoma and one of two cases, which initially mimicked sarcoma clinically and histologically in our hospital, was finally diagnosed as nodular fasciitis after requesting external consultation to several experienced pathologists. All of two cases had no evidence of recurrence at 2 years postoperatively. The lesions of unusually large dimension such as in our cases must be included in the differential diagnosis of soft tissue sarcoma. So we report two cases of nodular fasciitis of the thigh with a review of the current literature.

• Journal of the Korea Computer Graphics Society
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• v.25 no.3
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• pp.123-131
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• 2019

In this study, we modified CT images of femoral head in consideration of anatomically meaningful structure, proposing the method to augment the training data of convolution Neural network for segmentation of femur mesh model. First, the femur mesh model is obtained from the CT image. Then divide the mesh model into meaningful parts by using cluster analysis on geometric characteristic of mesh surface. Finally, transform the segments by using an appropriate mesh deformation algorithm, then create new CT images by warping CT images accordingly. Deep learning models using the data enhancement methods of this study show better image division performance compared to data augmentation methods which have been commonly used, such as geometric conversion or color conversion.

• Journal of the Korean Orthopaedic Association
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• v.55 no.4
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• pp.311-317
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• 2020

The most recent concept in anterior cruciate ligament reconstruction is an anatomical single bundle anterior cruciate ligament reconstruction. For an anatomical anterior cruciate ligament reconstruction, the tibial tunnel is made anterior than before, and the femoral tunnel is made in a lower and oblique direction compared to the classical method using the transtibial technique. The anteromedial portal technique, outside-in technique, and modified transtibial technique have been performed to produce femoral tunnels with anatomical positions. Each method has different advantages and disadvantages and is chosen based on the operator's preferences, experience, instruments, and implants.

• Journal of the Korean Society of Radiology
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• v.85 no.3
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• pp.531-548
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• 2024

Developmental dysplasia of the hip is a condition characterized by hip joint instability due to acetabular dysplasia in infancy, necessitating precise ultrasound examination. Legg-Calvé-Perthes disease is caused by a temporary disruption in blood flow to the femoral head during childhood, progressing through avascular, fragmentation, re-ossification, and residual stages. Slipped capital femoral epiphysis is a condition where the femoral head shifts medially along the epiphyseal line during adolescence due to stress, such as weight-bearing. Differentiating between transient hip synovitis and septic arthritis may require joint fluid aspiration. Osteomyelitis can be associated with soft tissue edema and osteolysis. When multiple lesions are present, it is essential to distinguish between Langerhans cell histiocytosis and metastatic neuroblastoma. This review will introduce imaging techniques and typical findings for these conditions.

• Journal of the Korean Society of Radiology
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• v.11 no.2
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• pp.145-155
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• 2017

The purpose of this study was to compare and analyze changes in body composition and bone mineral density (BMD) during combined exercise in premenopausal women who did not take regular diet or regular physical activity within 6 months, In addition to being able to recognize the importance of pre-menopausal women's health and exercise, it also provides basic data for the development of educational programs for early prevention of osteoporosis prevention education I want to. The average age of the subjects in their 30s was 35.44 years and their height was 158.89 cm in their 30s. The average age of the subjects in their 40s was 41.89 and their average height was 160.78 cm in their 40s. Body composition, BMI, and body fat percentage were higher in the 30s, and bone mineral content, lean body mass, skeletal muscle mass, body weight, body fat mass and waist circumference were higher in their forties. Lumbar spine BMD and femur density were higher in their 30s than their 40s. Body composition, skeletal muscle mass, and fat mass increased in the 30s body composition by age - related complex exercise in premenopausal women, body fat mass, body fat percentage, waist circumference decreased. Body mass, body fat, body fat percentage, and BMI decreased in the 40s. The lumbar spine, the lumbar spine, the lumbar spine, and the femur were increased in the lumbar spine, the lumbar spine, the femur, and the femur. In the post-analysis results, changes in body composition were statistically significant due to decrease in muscle mass, body weight, body fat mass and BMI after combined exercise. In the change of bone density, lumbar spine BMD was measured as lumbar spine 1, lumbar spine 2, lumbar spine 3, And the femur density was increase.

• Journal of the Korean Arthroscopy Society
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• v.10 no.2
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• pp.209-213
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• 2006

Purpose: Conventional transtibial approach for the anterior cruciate ligament (ACL) reconstruction tended to place the femoral tunnel in too vertical position (11 or 1 o'clock), which could provide the postoperative anteroposterior (AP) stability but not provided the rotational stability. Therefore we present a surgical technique to make the transtibial femoral tunnel at 10 or 2 o'clock position. Surgical approach: To make a transtibial femoral tunnel at the 10 or 2 o'clock position, the direction and position of the tibial drill guide was important. We set the tibial drill guide at $40{\sim}45$ degrees and the intraarticular guide tip was 1 mm anterior and medial to the conventional site. The starting point for the guide pin on the proximal tibia was proximal to the pes anserinus and anterior to the medial collateral ligament. The tibial tunnel was initially drilled 1mm less than the diameter of the graft. Then femoral offset guide could be easily placed at 10 or 2 o'clock position through the tibial tunnel. The tibial tunnel and the femoral tunnel of 30 mm in length were made with the reamer that was same size with the graft. Conclusion: We report a surgical technique to create a transtibial femoral tunnel at 10 or 2 o'clock position in ACL reconstruction to provide the rotational stability as well as the AP stability.