• 대한토목학회논문집
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• 제8권4호
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• pp.11-21
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• 1988

20세기에 들어서 포틀랜드 시멘트 콘크리트를 이용한 강성포장은, 콘크리트재료의 구조적인 휨강성과 큰 탄성계수 그리고 내구성을 고려한 경제성 등으로 세계 여러 나라에서 널리 이용되어져 왔다. 그러나, 완벽한 설계 및 시공에도 불구하고, 일부 콘크리트 포장도로에서는(예: 미국 Interstate-10 and 75, 한국의 88고속도로 및 중부 고속도로) 심각한 종적, 횡적 균열 및 침하현상 등으로 보수, 유지의 큰 어려움을 겪고 있는 바, 이러한 문제점을 구조역학적인 입장에서 유한 요소법을 이용한 콘크리트 포장구조의 해석을 통해, 차량 위치 및 온도변화에 따른 최대 파괴응력과 위치, 그리고 최대 처짐등을 고려 하므로써, 콘크리트 포장도로의 구조적인 문제점을 해결하는 데 있다. 본 논문에서는 요즘 미국에서 널리 이용되고 있는 경가가로줄눈(skewed joint)의 효과를 구조역학적으로 해석을 하였다.

• Journal of Yeungnam Medical Science
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• 제15권2호
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• pp.263-274
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• 1998

이 연구에서 저자들은 다음과 같은 결론을 얻었다. 1. 고관절 조영술은 수술전에 미리 유용한 정보를 줌으로써 수술전 계획을 세우고 수술을 체계적으로할 수 있을것으로 사료된다. 따라서 고관절 조영술은 도수정복 혹은 수술적 정복전에 필수적으로 시행하여야 할 것으로 사료된다. 2. 고관절 조영술은 비구 관절순, 원형인대의 평가에 매우 유용하였으며, 횡비구인대에 대한 정보는 제한적이었다. 3. 고관절 조영술은 단순 방사선 촬영에 비하여 중앙연각의 평가에 훨씬 유용하고 실제 병리적 소견에 합당한 정보를 주었다.

• 한국환경복원기술학회지
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• 제5권3호
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• pp.15-22
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• 2002

To analysis of the embanked slope stability using a jointed reinforcement, the internal stability and the external stability have to be satisfied, respectively. But, because the lengths of ready-made steel-grid were limited, the reinforcements must be connecting themselves to the reinforcing. In this study, the mechanical test was carried out to investigate the tensile failure and the pullout failure at the joint parts of them, which was based on the analysis of reinforced slope in field. Through the tensile tests in mid-air for the jointed steel-grid, the deformation behavior was seriously observed as follows : deformation of longitudinal member, plastic deformation of longitudinal member and of crank part. Those effects were due to the confining pressure and overburden pressure of the surrounding ground. The bearing resistance at jointed part of jointed steel-grid was due to the latter only. The maximum tensile forces were higher about 20kN~27kN than ultimate pullout resistance, but, the results of those was almost the same in mid-soil. The failures of steel-grid occurred at welded point both of longitudinal members and transverse members and of jointed parts. The strength of jointed parts itself got pullout force about 20kN, which was about 65% for ultimate pullout force of the longitudinal members N=2. To the stability analysis of reinforced structure including the reinforced slope, the studying of connection effects at jointed part of reinforcement members must be considered. Through the results of them, the stability of reinforced structures should be satisfied.

• 한국강구조학회 논문집
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• 제18권5호
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• pp.633-642
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• 2006

연속 강합성 교량에 종방향 프리스트레스를 도입해야 하는 프리캐스트 바닥판을 적용하기 위해서는 균열제어를 위한 사용성 설계가 이루어져야 한다. 특히, 2거더 교량의 경우에는 장지간 바닥판의 설계에서 요구되는 주철근 및 횡방향 프리스트레스와 합성설계를 위해 요구되는 전단포켓의 존재로 인해서 상세가 복잡해지게 된다. 이 논문에서는 2거더 연속강합성 교량의 프리캐스트 바닥판 채용을 위해서 필요한 유효 프리스트레스 크기의 산정과 상세의 단순화를 이루기 위해서 부착강도를 인정할 수 있는 채움재료의 선정 및 그 기준을 제시하였다. 또한, 장기거동에 대한 평가 방안을 제시하고 그 결과로부터 초기 프리스트레스의 크기 결정을 수행하여 기존의 설계의 개선 정도를 평가하였다. 일정 수준이상의 부착강도를 갖는 채움재료를 부모멘트가 크게 발생하는 영역에 사용하면 연속 강합성 교량의 전구간에 걸쳐서 일정한 종방향 프리스트레스 도입이 가능하고 이로 인해 상세의 단순화 및 경제성을 높일 수 있다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권3호
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• pp.246-250
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• 2004

Uni- or bilateral mandibular hypoplasia can be associated with various syndromes or is acquired after early traumatic or inflammatory disease in the temporomandibular joint(TMJ). Early treatment is necessary to avoid consequent impairment of midfacial growth. The standard treatment of these malformations consists of the application of bone grafts which can lead to unpredictable growth, but the new procedure of bone lengthening which was presented by McCarthy et al. represents a limited surgical intervention and therefore open up a new perspective of treatment, especially in younger children with severe deformities. Patients with hemifacial microsomia and facial asymmetry have a vertically short maxilla, a tilted occlusal plane, and a short mandible. A 14-years-old boy with facial asymmetry, who was fractured on both condyle and mandibular symphysis before 8 years ago, was treated by mandibular ramus lengthening, symphysial widening and surgically assisted rapid palatal expansion with corticotomy. After allowing 1 week for the healing of the periosteum, the distraction was performed at the rate of 0.5-1.0mm per day for 7 days on maxilla and 14 days on mandible. The device was maintained on maxilla and mandible for 12 weeks following distraction. The difference in ramus and mandibular transverse deficiency were corrected and facial asymmetry was improved with complex distraction osteogenesis.

• The Korean Journal of Pain
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• 제20권2호
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• pp.111-115
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• 2007

Background: Selective diagnostic blocks of the medial branches of the dorsal primary ramus are usually performed under the guidance of fluoroscopic or computed tomography. Recently, however, ultrasound guidance has been suggested as an altemative method. In this study, the distances between the vertebral structures were measured and compared with the values measured using magnetic resonance imaging (MRI) to assess the clinical feasibility of using ultrasound-guided block in Korean patients. Methods: Five male and 15 female patients were enrolled in this study. The target point of the medial branch block in our study was the groove at the base of the superior articular process, We measured the depth from the skin to the target point at the transverse process (d-TP) and to the most superficial point of the superior articular process (d-AP). Results: The d-TP and d-AP values measured under ultrasound guidance were concordant with the values measured using MRI. Conclusions: The images of the bony landmarks obtained under ultrasound examination could be useful for ultrasound-guided lumbar medial branch block.

• The Korean Journal of Pain
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• 제27권2호
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• pp.133-138
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• 2014

Background: The precise knowledge of anatomy and the region of transverse process (TP) and superior articular processes (AP) and their distance from the skin are important in blocking and treating lumbar facet syndrome. Evaluation of these anatomic distances from 3rd and 5th lumbar vertebrae in both sides and in different body mass index (BMI) in healthy volunteers might improve knowledge of ultrasound (US) lumbar medial branch nerve blocks (LMBB). Methods: Bilateral US in the 3rd and 5th lumbar vertebrae of 64 volunteers carried out and the distance between skin to TP and skin to AP was measured. These distances were compared on both sides and in different BMI groups. The analysis was done using SPSS 11. Analysis of variance was used to compare the means at three vertebral levels (L3-L5) and different BMI groups. P values less than 0.05 were considered statistically significant. The paired t-test was used to compare the mean distance between skin to TP and skin to AP on both sides. Results: The distance between skin to TP and skin to AP of 3rd vertebrae to 5th vertebrae was increased in both right and left sides (P < 0.001) from up to down. The mean distance from skin to TP were greater on the left side compared to the right in all three vertebral levels from L3 to L5 (P values 0.014, 0.024, and 0.006 respectively). The mean distance from skin to TP and the skin to AP was statistically significant in different BMI groups (P < 0.001). Conclusions: We found many anatomic distances which may increase awareness of US guided LMBB.

• 대한통합의학회지
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• 제10권2호
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• pp.73-83
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• 2022

Purpose : Low back pain (LBP) is reported as a risk of experiencing musculoskeletal disorders due to muscle stiffness and hypokinetics. The lumbar spine in an unstable state causes imbalance and lumbar instability. Therefore, This study examined the effects of lumbar stabilization exercise and self-complex exercise program on pain, function, psychosocial level, static balance ability, and transverse abdominal muscle (TrA) thickness and contraction ratio in patients with lumbar instability. Methods : The design of this is a randomized controlled trial (RCT). Twenty-six LBP patients participated in this study. Screening tests were performed and assigned to the experimental group (n=13) and control group (n=13) using a random allocation program. Both groups underwent a lumbar stabilization exercise program. In addition, the experimental group implemented the self-complex exercise program. All interventions were applied three times per week for four weeks. The quadruple visual analog (QVAS), the Korean version of the Oswestry disability index (K-ODI), Korean version of fear-avoidance belief questionnaire (FABQ), static balance ability, TrA thickness, and contraction ratio were compared to evaluate the effect on intervention. Statistical significance was set at 𝛼=.05. Results : Both groups showed significant differences before and after the intervention in QVAS, K-ODI, FABQ, static balance ability, and TrA thickness in contraction (p<.05). In addition, significant differences in K-ODI and FABQ were observed between the experimental group and control group (p<.05). Conclusion : A lumbar stabilization exercise and self-complex exercise program resulted in reduced dysfunctions, psychosocial stability in patients with lumbar instability. Therefore, Lumbar stabilization exercise and self-complex exercise program for patients with lumbar instability are effective method with clinical significance in improving the function and psychosocial stability.

• PNF and Movement
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• 제20권3호
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• pp.451-459
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• 2022

Purpose: Temporomandibular disorder (TMD) is a common musculoskeletal problem that causes pain in and disability of masticatory muscles, the temporo-mandibular joint (TMJ), and related structures. The purpose of this study was to compare pressure pain thresholds (PPTs) of masticatory muscles, cervical ranges of motion (ROM), and pelvic mobility during gait of subjects with or without TMD. Methods: In this study, pain thresholds and changes in the mobility of the cervical vertebrae and pelvis were measured in 25 patients with TMD and 25 healthy controls. Using a pressure algometer, the pressure pain thresholds (PPTs) of the masseter and temporalis muscles were measured in both groups. A gyroscope sensor with a mobile application was used to determine cervical ROM in the frontal and sagittal planes. A 3D-motion analysis system was used to evaluate pelvic mobility in the sagittal, frontal, and transverse planes during gait. Results: The TMD group showed significantly decreased PPTs of masseter and temporalis muscles compared with the control group (p < 0.05). Cervical ROM in flexion, extension, and lateral bending were significantly decreased in the TMD group compared with the control group (p < 0.05). In addition, antero-posterior pelvic tilt was significantly decreased in the TMD group (p < 0.05). Conclusion: The results of the current study suggest that there are close anatomical and functional relationships between TMD and muscle chains related to the cervical spine and pelvis. Therefore, more comprehensive body posture assessments, especially of painful areas, should be undertaken when studying TMD patients.

• Clinical Pain
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• 제18권2호
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• pp.92-96
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• 2019

Torticollis is an abnormal, asymmetric head or neck position which usually caused by imbalance of paracervical muscles. The traumatic torticollis can be caused by following events; atlantoaxial rotatory subluxation, atlantoaxial dislocation, cervical vertebral fractures, and injury to the cervical musculature. Especially, acute traumatic atlantoaxial rotatory subluxation usually presents limitation of cervical range of motion without pain or neurologic deficit. We report a case of a 58 year-old man who developed the acute atlantoaxial rotatory subluxation right after the chiropractic therapy, which induced the limitation of cervical range of motion to 52.5% of normal range. The magnetic resonance image revealed the facture of the odontoid process and the partial injury in transverse ligaments of the atlas. He underwent intramuscular botulinum toxin injection and 10 days of continuous cervical traction 15 hours a day using a 5 kg weight. The range of the cervical motion restored up to 90.2% of normal range.