• Journal of Biomedical Engineering Research
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• v.25 no.3
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• pp.171-182
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• 2004

This study investigates the biomechanical efficacies of vertebroplasty which is used to treat vertebral body fracture with bone cement augmentation for osteoporotic patients using image and finite element analysis. Simulated models were divided into two groups: (a) a vertebral body, (b) a functional spinal unit(FSU). For a vertebral body model, the maximum axial displacement was investigated under axial compression to evaluate the effect of structural integrity. The stiffness of each FE model simulated was normalized by the stiffness of intact model. In the case of FSU model, 3 types of compression fractures were formulated to assess the influence on spinal curvature changes. The FSU models were loaded under compressive pressure to calculate the change of spinal curvature. The results according to the various factors suggest that vertebroplasty has the biomechanical efficacy of the increment of structural reinforcement in a patient who has relatively high level of BMD and a patient with the amount of 15％, PMMA injection of the cancellous bone volume. The spinal curvatures after compression fracture simulation vary from 9$^{\circ}$ to 17$^{\circ}$ of kyphosis compared to that the spinal curvature of normal model was -2.8$^{\circ}$ of lordosis. These spinal curvature changes cause the severe spinal deformity under the same loading. As the degree of compressive fracture increases the spinal deformity also increases. The results indicate that vertebroplasty has the increasing effect of the structural integrity regardless of the amount of PMMA or BMD and the restoration of decreased vertebral body height may be an important factor when the compressive fracture caused the significant height loss of vertebral body.

• The Journal of Korea CHUNA Manual Medicine
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• v.3 no.1
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• pp.167-174
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• 2002

Stable compression fractures are most often caused by trauma as traffic accidents. Stable compression fractures can refer pain to the mid-back, which is characterized by the pain in the thoracolumbar spinous prosess. recently we experienced a 19 years old man who had lumbago originating from Stable compression fractures and condition was improved through burning acupunture.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1775-1780
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• 2011

In this paper, it is analyzed about the mechanical characteristics of pedicle screw system which is a artificial implant for surgery to treatment serious lumbar vertebra diseases. The disk of lumbar vertebra to be fixed by pedicle screw system shows regressive phenomena. But if flexible rod, to give a flexibility(under 6 degree) to fixable disk is applied, it can protect against the degeneration of disk. This research is carried out a mechanical characteristic of pedicle screw system used flexible rod through finite elements analysis, and then flexible rod system was verified about safe movement through compression, tension and torsion test which is the pedicle screw system official recognition test(ASTM F 1717).

• The KIPS Transactions:PartB
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• v.10B no.5
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• pp.503-508
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• 2003

Since surgical treatment of the spine should overcome neurological compromises, the operative procedures need to be carefully planned and carried out with high degree of precision. Percutaneous vertebroplasty is a surgical procedure that was introduced for the treatment of compression fracture of the vertebrae. This procedure includes puncturing vertebrae and filling with polymethylmethacrylate (PMMA). Recent studies have shown that the procedure could provide structural reinforcement for the osteoporotic vertebrae while being minimally invasive and safe with immediate relief of pain. However, failures of treatment due to excessive PMMA volume injection have been reported as one of complications in vertebroplasty. It is believed that the control of PMMA volume is one of the most critical factors that can reduce the incidence of complications. Therefore, clinical success of vertebroplasty can be dependent on the volume of PMMA injection for a given patient. In this study, the optimal volume of PMMA injection for vertebroplasty was predicted based on the image analysis of a given patient.

• Proceedings of the Korea Contents Association Conference
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• 2012.05a
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• pp.365-366
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• 2012

본 연구는 교각운동시 불안정한 지지면과 안정적인 지지면을 제공하여 체간 및 하지의 근 활성도의 변화를 알아보고자 하였다. 이 연구의 대상자는 20대 남, 여 14명이었다. 실험방법은 일반적 교각자세와 다이나믹 에어쿠션을 이용한 교각자세를 실시한 후에 무선 8채널 표면근전도 검사기를 이용하여 체간부의 척추기립근, 복직근, 대퇴의 대퇴직근, 외측 슬괵근, 하퇴부의 전경골근, 비복근 외측두에서 근활성 정도를 측정하였다. 체간부의 척추 기립근, 대퇴이두근, 가자미근은 불안정한 지지면에서 근활성도가 높게 나타났다(p<.05). 따라서, 교각운동에서 불안정한 지지면의 제공은 신체의 배측에 위치한 근육의 활성화를 나타내어, 교각운동시 지지면의 안정성의 변화만으로도근육활성도의 변화가 가능함을 알 수 있었다.

• Composites Research
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• v.34 no.3
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• pp.186-191
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• 2021

The lumbar spinal fusion is a treatment performed to restore the stability of the degenerated lumbar. In this study, the intervertebral discs between two or more segments are removed and a bone graft is inserted to harden the segments. The pedicle screw system is inserted to vertebral bodies to fix two or more segments so that they can be firmly fused. In this study, a total of 7 patient-specific lumbar finite element models were created and pedicle screw systems were installed. The connecting rods made of titanium and CFR-PEEK was inserted to the generated models. Finite element analysis was conducted for four representative spine behaviors and statistical analysis was performed to investigate the biomechanical effects by the material properties of connecting rods. The intradiscal pressure of adjacent segments and the range of motion of the joints of each segment were investigated. In the subjects who used CFR-PEEK instead of Ti for connecting rods, the intradiscal pressure of adjacent segments tend to decrease and the range of motion of each segment tend to increase. However, no statistically significant difference in tendency was observed under all loading conditions.

• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.1
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• pp.53-59
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• 2010

The spatial variability in the food chain structure of an estuarine environment(Nanakita estuarine, Japan) was investigated using stable carbon and nitrogen isotope. Potential organic matter sources(TP:Terrstrial Plant, MPOM:Marine particulate organic matter, BMA:Benthic microalgae, EPOM:Estuarine particulate organic matter), sedimentary organic matter and benthic invertebrates(Nuttallia olivacea and Nereidae) were sampled at four locations with different tidal flat types(e.g. sanddy, sanddy-muddy and muddy). The main objective of the present study was to determine food sources of Nuttallia olivacea and Nereidae along with small-scale spatial variability within the community of benthic invertebrates. TP(${\delta}^{13}C=-26.6{\pm}0.76$ and ${\delta}^{15}N=2.7{\pm}0.31$) and EPOM(${\delta}^{13}C=-25.5{\pm}0.13$ and ${\delta}^{15}N=5.2{\pm}0.46$) were isotopically distinct from BMA(${\delta}^{13}C=-16.3$ and ${\delta}^{15}N=6.2$) and MPOM(${\delta}^{13}C=-19.6{\pm}0.08$ and ${\delta}^{15}N=8.9{\pm}1.70$). ${\delta}^{13}C$ values of sedimentary organic matter showed a distinct gradient in the range of -27.4 to -22.8‰ with a declining trend from the upstream to the downstream stations. The stable carbon and nitrogen isotope values of benthic invertebrates in the study site was -22.8 to -18.4‰ for ${\delta}^{16}C$ and 8.1 to 11.9‰ or ${\delta}^{15}N$, respectively. Mixing model(Isosource) calculations based on stable isotope measurements showed that benthic invertebrates of Nuttallia olivacea and Nereidae were found to be dominated by MPOM and BMA in stations. Whereas, TP and EPOM showed little influence to benthic invertebrates. The current result suggests that the different contribution for benthic invertebrates should be affected by both seasonal variation and physical factor among stations.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.46-46
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• 2010

최근 상압 저온 플라즈마에서 발생되는 UV와 화학적 활성종들을 이용한 체내 조직 분해 처리, 피부 및 혈관 표면 처리, 대기 및 액체 정화 처리 등의 생체 의료적 응용이 활발하게 연구되고 있다. 이러한 플라즈마에서는 처리 대상 외의 생체 조직의 손상을 최소화 할 수 있는 기술이 필요하며, 이 조건이 확보된 상태에서 처리 목표 대상에 따른 플라즈마 특성, 즉 선택적 생성종 제어와 플라즈마 온도를 안정적으로 관리할 수 있어야 한다. 인체 내부 조직에 대하여 유효 활성종 등의 직접적인 작용이 필요할 경우 밀리미터 크기 이하의 미세침습성 플라즈마를 활용하게 된다. 이 경우 방전 특성을 간접적으로만 관측 가능하여 주변 조직과 플라즈마 간의 상호 영향 등이 고려되어야 하므로 직접적인 관측이 가능한 인체 외부에서 발생된 플라즈마에 비해서 더욱 정교한 제어가 필요하다. 본 연구에서는 미세 침습성 플라즈마의 발생 메커니즘 및 특성 분석을 수행하여 척추 디스크 탈출 치료 시술에 활용하기 위한 연구를 수행하였다. 처리 대상 조직으로의 접근 시 주변 조직의 손상을 막기 위하여 수 밀리미터 이하의 미세한 전극을 이용하였으며 전기 전도성을 띄는 인체 내부에서 절연공간의 확보를 위해 전극 표면에서 기포를 발생시켜 플라즈마 방전이 가능한 조건을 확보하였다. 또한 플라즈마 방전이 중단되거나 혹은 갑작스런 열 플라즈마로의 천이로 인해 생체에 심각한 열 손상을 초래하는 현상을 방지하기 위하여 발생 플라즈마와 주변 디스크간의 상호 영향을 통한 플라즈마의 동적인 특성 변화 및 안정적인 플라즈마 발생을 위한 조건을 도출하였다. 이를 실제 임상 실험에 활용한 결과를 소개하고 아울러 차세대 의료용 플라즈마 발생 장치 개발을 위한 플라즈마 학계의 관심을 이끌어 보고자 한다.

• The Korean Journal of Food And Nutrition
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• v.11 no.2
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• pp.165-170
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• 1998

Diagnostic radiology and conservative management for S75 patient with L1 lumbar fracture by traffic accidents were discussed with references, and then the obtained results were as follows ; 1. Wedging compression fractures with 10% deformity was confirmed at anterior vertebral body of L1 lumbar spine through lateral plain X-ray film. 2. Irregular bony fractures were observed at anterior vertebral body of L1 lumbar spine by CT scans, anatomically T12-L1 sites showed highly frequency of injuries, Denis's fracture type was classified as multiple compression fracture at anterior column without abnormal middle and posterior column, also no Cobb's angle, and then Frankel's neurological classification was E grade. 3. Orthopaedic treatments were performed with conservative methods. With rest on the bed, anti-in-flammatory medication, electrolyte and nutritional solution, the pain diminished. 4. After 3 weeks, rehabilitation was worked with putting on polyethylene back corset, although pains remained slightly until after 8 weeks, thereafter the spine showed gradually stability.

• Ecology and Resilient Infrastructure
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• v.9 no.1
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• pp.15-23
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• 2022

This study was conducted to investigate in relation to characteristic of macroinvertebrates in conventional and organic paddy fields. The investigation was conducted five times a year for Suwon, Ansung, Boeun, Gunsan, Gimje, Hamyang, divide into conventional paddy fields and organic paddy fields from 2009 to 2011. The macroinvertebrates collected from the surveyed between conventional and organic paddy fields belonged to 84 species, 47 families, 16 orders, and 6 classes in 3 phyla. In the habitat orientied groups, climbers, swimmers and sprawlers were considerably occupied in conventional and organic paddy fields. In relation to the functional feeding groups, predators such as Odonata, Coleoptera, and Hemiptera were only the highest in paddy field ecosystem, regardless of cultivation method. As a result of community stability analysis, orgainc paddy fields has been identified much as species high resistance and resilience to environmental change in paddy field ecosystem. Species belonging to the I groups is considered to be important in organic paddy field such as Sternolophus rufipes, Hydrochara affinis, Helochares nipponicus, which has high mobility. In conclusion, it was found that the introduction of coleoptera as a food source was higher than that of conventional paddy fields in organic paddy field where primary consumers were abundant such as Chironomidae spp. and Dixidae sp..