• 제목/요약/키워드: disc compression force

검색결과 18건 처리시간 0.023초

압축력을 병용한 하악골 신장술 (MANDIBULAR DISTRACTION OSTEOGENESIS WITH COMPRESSION FORCE - BONE DENSITY, HISTOLOGICAL FINDINGS AND TMJ RESPONSE)

  • 황영섭;허준;김욱규;박성진;황대석;김용덕;정인교;김규천
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제28권6호
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    • pp.531-548
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    • 2006
  • The purpose of this study was to investigate the biomechanical, histologic findings of distracted regenerate and TMJ response in modified distraction osteogenesis (DO) technique combined with compression force as biomechanical stimulation method which has been suggested in 2002, and developed thereafter by authors. This study was performed with two experiments. First experiment was designed to explore the optimal ratio of compression force versus distraction force for the new DO technique. Second experiment was planned to evaluate the reaction of TMJ tissue, especially condyle, disc after application of the DO technique with compression force. Total 52 New Zealand adult male-rabbits with 3.0kg body weight were used for the study. For the first study, 30 adult male-rabbits underwent osteotomy at one side of mandibular body and a external distraction device was applied on each rabbit with same manner. In the control group of 10 rabbits, final 8 mm of distraction with 1 mm rate per day was done with conventional DO technique after 5 latency days. For the experimental group of 20 rabbits, a compression force with 1 mm rate per day was added to the distracted mandible on 3-latency day after over-distraction (over-lengthening). As the amount of the rate of compression versus distraction, experimental subgroup I (10 rabbits) was set up as 2 mm compression versus 10 mm distraction (1/5) and experimental subgroup II (10 rabbits) was set up as 3 mm compression versus 11 mm distraction (about 1/3). All 30 rabbits were set up to obtain final 8 mm distraction and sacrificed on postoperative 55 day to analysis on biomechanical, and histologic findings of the bone regenerates. For second study, 22 adult male-rabbits were used to evaluate TMJ response after the DO method application with compression force. In the control group, 10 rabbits was used to be performed with conventional DO method, on the other hand, in a experimental group of 10 rabbits, 10 mm distraction with 2 mm compression (1/5 ratio) was done. The remaining 2 rabbits served as the normal control group. Histomorphologic examinations on both condyle, histological studies on condyle, disc were done at 1, 2, 3, 4, 7 weeks after distraction force application. The results were as follows: 1. On the bone density findings, the experimental group II (force ratio - 1/3) showed higher bone density than the other experimental group (force ratio - 1/5) and control group (control group - $0,2906\;g/cm^2$, experimental group I - $0.2961\;g/cm^2$, experimental group II - $0.3328\;g/cm^2$). 2. In the histologic findings, more rapid bone maturation like as wide lamellar bone site, more trabeculae formation was observed in two experimental groups compared to the conventional DO control group. 3. In morphologic findings of condyle, there were no differences of size and architecture in the condyle in the control and experimental groups. 4. In histologic findings of condyles, there were thicker fiberous and proliferative layers in experimental group than those of control group until 2 weeks after distraction with compression force. But, no differences were seen between two groups on 3, 4, 7 weeks after compression. 5. In histologic findings of disc, more collagen contents in extracellular matrix, more regular fiber bundles, and less elastin fibers were seen in experimental group than control group until 2 weeks after distraction with compression. But, no differences were seen between two groups on 3, 4, 7 weeks after distraction with compression. From this study, we could identify that the new distraction osteogenesis technique with compression stimulation might improve the quality of bone regeneration. The no remarkable differences on TMJ response between control and experimental groups were seen and TMJ tissues were recovered similarly to normal TMJ condition after 3 weeks.

정적 부하 작업에서 EMG 모델과 세가지 최적화 모델을 이용한 척추 부하 평가 (Prediction of the Spinal Load during Static Loading Conditions using EMG model and Three Optimization models)

  • 송영웅;정민근
    • 한국산업보건학회지
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    • 제15권1호
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    • pp.61-70
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    • 2005
  • This study investigated the spinal loads(L5/S1 disc compression and shear forces) predicted from four biomechanical models: one EMG model and three optimization models. Three objective functions used in the optimization models were to miminize 1) the cubed muscle forces : MF3, 2) the cubed muscle stress : MS3, 3) maximum muscle intensity : MI. Twelve healthy male subjects participated in the isometric voluntary exertion tests to six directions : flexion/extension, left/right lateral bending, clockwise/ counterclockwise twist. EMG signals were measured from ten trunk muscles and spinal loads were assessed at 10, 20, 30, 40, 50, 60, 70, 80, 90%MVE(maximum voluntary exertion) in each direction. Three optimization models predicted lower L5/S1 disc compression forces than the EMG model, on average, by 31%(MF3), 27%(MS3), 8%(MI). Especially, in twist and extension, the differences were relatively large. Anterior-posterior shear forces predicted from optimization models were lower, on average, by 27%(MF3), 21%(MS3), 9%(MI) than by the EMG model, especially in flexion(MF3 : 45%, MS3 : 40%, MI : 35%). Lateral shear forces were predicted far less than anterior-posterior shear forces(total average = 124 N), and the optimization models predicted larger values than the EMG model on average. These results indicated that the optimization models could underestimate compression forces during twisting and extension, and anterior-posterior shear forces during flexion. Thus, future research should address the antagonistic coactivation, one major reason of the difference between optimization models and the EMG model, in the optimization models.

모 연와제조 공장 근로자의 작업과 관련된 요통 및 대책에 관한 연구 (A Study on the Work-related Low Back Pain of Workers at a Refractories Manufacturing Factory)

  • 정희경;임현술;김지용
    • 한국산업보건학회지
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    • 제7권2호
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    • pp.289-297
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    • 1997
  • Work-related low back pain(below LBP) is one of the major cause of morbidity, disability, limitation of activity and economic loss. Therefore the work-related LBP is one of the major issue in the field of industrial safety and health. This study was performed for detecting the risk factors and proposing the effective control programs of work-related LBP. The subjects were male workers employed at the welding and metal factory. The data was collected by self-reported questionnaire, interview and checking abdomen muscular and grasping power for two days on October, 1993. The contents of questionnaire were as follow: the experience of LBP, general characteristics, physical characteristics, employment status, type of work and working environment. The number of cases was 104 with a history of work-related LBP, so the prevalence of work-related LBP was 35.0%, and the number of controls was 140 without any history of LBP. As a result, marital status, educational level, abdomen muscular power, tenure, category of job, satisfaction of job, working posture, satisfaction for table and chair and lifting materials showed a statistical significance between the case and control groups. 284 Lifting jobs were quantified by NIOSH lifting equation method and ergonomic computer modelling methods. There were no significant differences in the action limit and disc compression force between group with LBP and without LBP. But in the lifting frequency and cumulative disc compression force there were significant differences. Therefore work-related LBP should be prevented by the ergonomic and environmental control.

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근전도를 이용한 L5/S1에서의 요추부하 평가에 관한 연구 (A Study on the Evaluation of Compression Force at the L5/S1 using Electromyography)

  • 양성환
    • 산업경영시스템학회지
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    • 제20권44호
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    • pp.323-332
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    • 1997
  • This study evaluated the compression force at the L5/S1 disc using EMG(Electromyography). EMG signals were analyzed under the condition of fixed vertical factor (20Cm∼80Cm), two horizontal factors (35Cm, 55Cm), and two weight factors (10Kg, 25Kg) 2 times per minute for each posture. Also, the result was compared with the compression force of each posture which computated by the equation of NIOSH(National Institute for Occupational Safety and Health) guide to manual lifting(1991). The experimental result show that EMG signals have more an effect on the Weight than the Horizontal factors. Also, there are not significant differences on the analysis result of EMG signals between Health members and not, because the body buildings which doing Health members are not enhanced the motor unit due to the MMH(Manual Material Handing).

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자전거를 탈때의 정적 생체역학 모형에 관한 연구 (Estimation of Loads applied to a Rider using a static Biomechanical Model.)

  • 반영환;장필식
    • 산업경영시스템학회지
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    • 제20권43호
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    • pp.197-204
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    • 1997
  • Torques on each joint, the compression on L5/S1 disc, the force on hand of a rider are estimated using a static biomechnic model. Forces that the rider applies to the pedals, saddle and handle during starting and speeding are estimated using static mechanics. Physical stress is considered accroding to handle height and horizontal distance between handle and pedal. When handle height is higher in normal speeding, the force on handle and sum of torques on each joint decreases.

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원주가압형 디스크의 형상변화가 온도분포에 미치는 영향에 관한 연구 (A Study on Effect of Temperature Distribution in Shape Change of the Circumferential Pressing Type Disc)

  • 김형훈;이성욱;한동섭;한근조
    • 한국기계가공학회지
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    • 제6권4호
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    • pp.86-91
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    • 2007
  • The heat generated by the brake system of vehicles results in reduction of friction force on the brake surface and vibration when breaking. These problems play essential part in break's performance. To solve these problems, extensive research has been conducted such as drilling cooling holes on the brake pud, accommodating ventilated holes and etc. In this study, we suggest the compression of brake in circumferential direction in order to improve its cooling performance. And we analyzed comparing temperature distribution which is generated accomplishing heat analysis at each disc.

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척추경 나사못을 이용한 척추 유합술에서 고정범위에 따른 인접 추간판의 압축 거동 분석 (Analysis of Compression Behavior on Intervertebral Disc L4-5 in Pedicle Screw System Instrumented Lumbar Spine under Follower Load)

  • 안면환;안종철;이수호;정일섭;이춘열;이장우
    • Journal of Yeungnam Medical Science
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    • 제20권2호
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    • pp.160-168
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    • 2003
  • 요추부 척추에 기구를 시술한 유한요소 복합체 모델을 이용하여 제 4-5 요추간판에 대한 해석을 수행한 결과, 근육의 작용을 케이블과 케이블 가이드로써 단순화 모사한 follower 하중에서 수직하중인 경우보다 높은 압축력을 나타내어 더욱 안정함을 보였고 불안정성의 원인이 되는 전단력과 굽힘모멘트의 발생은 미미하였다. 장분절 고정에 의한 인접 분절에 전단력이 증가됨을 실험적으로 보였는데, 이는 장분절 고정이 퇴행성 변화 촉진에 기여할 것으로 추정된다.

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암반강도 및 압입깊이에 따른 디스크커터의 최적간격 산정을 위한 개별요소법 기반 수치해석 연구 (A numerical study on the optimum spacing of disc cutters considering rock strength and penetration depth using discrete element method)

  • 이상연;송기일;정주환
    • 한국터널지하공간학회 논문집
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    • 제22권4호
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    • pp.383-399
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    • 2020
  • 디스크커터의 간격을 최적화하는 것은 TBM 커터헤드의 설계의 핵심요소로, TBM의 굴진성능을 좌우한다. 실대형 선형절삭시험은 디스크커터의 간격 산정을 위해 가장 신뢰성 및 정확도가 높은 시험으로 알려져 있으나 실대형 실험을 위해 경제적 및 시간적 비용이 소요되는 단점이 있다. 본 연구에서는 개별요소법 기반의 수치해석 연구를 통해 암반의 일축압축강도 및 압입깊이에 따른 비에너지-S/P비 간의 경향성을 분석하였고, 17인치 디스크커터의 최적 간격을 도출하였다. 수치해석모델의 적정성을 검토하기 위하여 디스크커터에 작용되는 회전력을 CSM 모델과 비교·검토하였다. 선형절삭시험에 대한 수치해석 결과, 디스크커터에 작용되는 회전력은 CSM 모델의 이론식으로부터 도출한 회전력과 유사한 것으로 분석되었다. 5가지(50 MPa, 70 MPa, 100 MPa, 150 MPa, 200 MPa)의 일축압축강도에 대한 수치해석 결과, 암반강도가 증가할수록 디스크커터의 최적간격의 범위는 감소하는 경향을 보였으며 80~100 mm범위에서 최소 비에너지를 보이는 것으로 확인되었다. 이는, 기존에 보고된 디스크커터의 최적 간격과 일치되는 경향으로써, 본 연구를 통해 산정된 디스크커터 간격을 밑받침한다.

새로운 방식의 나사형 인공디스크 고정체 해석 (Finite Element Analysis of a Newly Designed Screw Type Fixture for an Artificial Intervertebral Disc)

  • 임종완;양현익
    • 대한의용생체공학회:의공학회지
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    • 제31권1호
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    • pp.56-66
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    • 2010
  • The various total replacement artificial discs have developed because spinal fusion has shown a lesser mobility of an operated segment and an accelerated degeneration at adjacent discs. But almost artificial discs have not yet been reached on the substitute surgery of fusion because many problems such as those clinical success rates were not more than them of fusion have not solved. In this paper, vertically inserted assemble-screw fixture in vertebrae was proposed to improve the fixed capability of artificial disc. And also, to evaluate the design suitability of newly designed screw-type, including fixtures of commercial discs such as wedge and plate type, the 1/4 finite element model with a vertebra and various implanted fixtures were generated, and next, 3 bending motions such as flexion, bending and twisting under the moment of 10Nm and compression under the force of 1000N were considered, respectively and finally, FE analyses were performed. Results of three fixture types were compared, such as Range of Motion and maximal stress, and so on. For ROM, the screw type was average 58% less than the wedge type and was average 42% less than the plate type under all loading conditions. For average stress ratio at closer nodes between vertebra and each fixture, the wedge type was the lowest as minimum 0.02 in twisting, screw types were the highest as maximum 0.28 in compression. As the results of using cement material, it was predicted that the instability problem of the wedge type was better solved. The screw type which could be increased by implanting depth according to the number of assembling mid screws, showed that the decreased tendency of ROMs and maximal cancellous bone stresses. In further study, controlling the number of assembling screws that was suitable for a patient's bone quality, development of surgical tools and keeping on design supplementations, which will be able to develop the competitive artificial disc.

유한요소 모델을 이용한 충격력에 따른 경추부의 응답특성 해석 (Impact Analysis of the Cervical Spin using a Finite Element Model)

  • 김영은;박덕용;이춘기
    • 한국자동차공학회논문집
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    • 제7권5호
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    • pp.249-257
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    • 1999
  • A three dimensional finite model of a human neck has been developed in an effort to study the mechanics of cervical spin while subjected to vertical impact. This model consisting of the vertebrae from C1 through C7 including posterior element and ligaments was constructed by 2mm thick transverse CT cross-sections and X-ray film taken at lateral side. Geometrical nonlinearity was also considered for the large deformation on the disc. ABAQUS package was used for calculation and its results were verified comparing with responses of a model under static loading condition with published in-vitro experimental data. There were more cervical fracture in the restrained (compression) mode than in the nonrestrained (flexion-compression and extension-compression) mode. Upper cervical(C1-C2) injuries were observed under compression-extension modes, while lower cervical injuries occurred undjer compression-flexion modes. Posterior ligament distraction without bony damage at the upper cervical spin(C1-C2) were observed secondary to C5-C7 trauma in compression-flexion modes.

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