• 비파괴검사학회지
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• 제31권5호
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• pp.494-499
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• 2011

인체 근골격 시스템에 대한 다물체 동역학 모델을 이용한 동작중의 인체 내부의 생체역학 분석 및 평가 기술에 대하여 기술하였다. 의료영상과 사체실험 결과를 기본으로 하는 인체 다물체 동역학 모델과 3차원 동작분석 시스템을 이용한 인체 동작분석기술을 이용하여 생체내 발생하는 관절기구학, 관절모멘트 관절접촉력 및 근력을 예측하는 기술을 보행과 팔굽혀펴기 두 동작에 적용하였다. 본 연구에서 개발한 인체 다물체 동역학 모델링 기술과 3차원 동작분석기술은 다양한 동작을 수행하는 생체의 분석 및 평가 기술로 활용성이 높을 것으로 생각한다.

• 대한물리치료과학회지
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• 제9권3호
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• pp.161-170
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• 2002

knee injuries are among the most common problems confronting patients, physical therapist and physicians. since the bony structure provides little stability, the soft tissues are required to withstand high forces, often resulting in tissue overload and injury immobilization of the knee in the presence of a hemarthrosis usually leads to proliferation of intraarticular connective tissue adhesions and pint fibrosis. the physical basis of treating scar tissue is early controlled motion. the management of the knee with increased instability is to strengthening the muscles to properly treat an soft tissue injuries, physical therapist should know about the anatomic structures and biomechanical function of the knee joint, in this review article, we discuss the physiologic properties of soft tissue, biomechanical observation in fibrous connective tissue, managing soft tissue contractures, principles in treating scar tissue and treatment of the knee with increased instability.

• 대한기계학회논문집A
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• 제33권7호
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• pp.645-651
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• 2009

Previous studies have introduced the technique of spinous process osteotomy to decompress spinal stenosis, a procedure which aims to afford excellent visualization while minimizing destruction of tissues not directly involved in the pathologic process. However, biomechanically it has not been investigated whether the sacrifice of posterior spinous process might have potential risk of spinal instability or not, even though supra-spinous and inter-spinous ligaments are preserved. Therefore the aim of this study is to evaluate the biomechanical properties after spinous process osteotomy, using finite element analysis. The model of spinous process osteotomy exhibited no significant increase in disc stress or change in segmental range of motion. It is due to the fact that the instability of lumbar spine has been maintained by the two-types of ligaments compared with the prior surgical technique. Therefore, according to the finite element result on this study, this osotetomy was considered to be a clinically safe surgical procedure and could not cause the instability of the lumbar spine.

• The Journal of Advanced Prosthodontics
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• 제14권3호
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• pp.182-202
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• 2022

PURPOSE. The aim of this study is to summarize various biomechanical aspects in evaluating the long-term stability of dental implants based on finite element method (FEM). MATERIALS AND METHODS. A comprehensive search was performed among published studies over the last 20 years in three databases; PubMed, Scopus, and Google Scholar. The studies are arranged in a comparative table based on their publication date. Also, the variety of modeling is shown in the form of graphs and tables. Various aspects of the studies conducted were discussed here. RESULTS. By reviewing the titles and abstracts, 9 main categories were extracted and discussed as follows: implant materials, the focus of the study on bone or implant as well as the interface area, type of loading, element shape, parts of the model, boundary conditions, failure criteria, statistical analysis, and experimental tests performed to validate the results. It was found that most of the studied articles contain a model of the jaw bone (cortical and cancellous bone). The material properties were generally derived from the literature. Approximately 43% of the studies attempted to examine the implant and surrounding bone simultaneously. Almost 42% of the studies performed experimental tests to validate the modeling. CONCLUSION. Based on the results of the studies reviewed, there is no "optimal" design guideline, but more reliable design of implant is possible. This review study can be a starting point for more detailed investigations of dental implant longevity.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1316-1319
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• 2003

The micromovements and stress distributions of cancellous bone in dental implant system play important roles in evaluating chewing function of an implant system. The micromovements and stress distributions in dental implant system generally depend on the chewing force and bone properties. Three dimensional nonlinear finite element analysis has been employed to investigate this issue quantitatively. Chewing forces and bone properties are classified into several groups and three types of implants involving one classical cylindrical type and two expandable implants are investigated in this paper.

• 농업과학연구
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• 제23권2호
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• pp.233-241
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• 1996

The mechanical properties of biological materials depend on numerous factors. The majority of these relationships are still unknown today, especially with regard to their quantitative characteristics. The reason is that biological materials constitute biomechanical systems of very complex construction, whose behavior cannot be characterized by simple physical constants, as for example can that of engineering materials. The objectives of this investigation were to determine the compression creep and recovery properties of rice stalks at various levels of applied load The compression creep and recovery behavior of the rice stalk could be predicted precisely by rheological model which approached closely to the measured values. But the coefficients of the Burgers recovery model were different from those of the creep model. The Steady state creep behavior occurred at the higher level of force and the logarithmic creep behavior occurred at the lower level of force. The mechanical model being expected the creep behavior in relation with the level of applied load, which was well explained that the rice stalk might be visco-elastic material.

• 한국운동역학회지
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• 제25권1호
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• pp.103-111
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• 2015

Objective : The purpose of this study was to evaluate the effect for running shoes with resilience of midsole on biomechanical properties. Methods : 10 healthy males who had no history of injury in the lower extremity with an average age of 26.5 year(SD=1.84), height of 172.22 cm(SD=4.44) and weight of 67.51 kg(SD=6.17) participated in this study. All subjects ran on the treadmill wearing three different running shoes. Foot pressure data was collected using Pedar-X system(Novel Gmbh, Germany) operating at 100 Hz. Surface EMG signals for biceps femoris, rectus femoris, vastus lateralis, medial lateralis, tibialis anterior, medial gastrocnemius, soleus and peroneus longus were acquired at 1000 Hz using Bignoli 8 System(Delsys Inc., USA). To normalize the difference of the magnitude of muscle contractions, it was expressed as a percentage relative to the maximum voluntary contraction (MVC). The impact resilience of the midsole data was collected using Fastcam SA5 system(Photron Inc., USA). Collected data was analyzed using One-way ANOVA in order to investigate the effects of each running shoes. Results : TPU midsole was significantly wider in contact area than EVA, TPE midsole in midfoot and higher in EMG activity than EVA midsole at biceps femoris. TPE midsole was significantly wider in contact area than EVA midsole in rearfoot and higher in peak pressure than EVA midsole in forefoot. EVA midsole was significantly higher in EMG activity than TPU midsole at tibia anterior. In medial resilience of midsoles, TPE midsole was significantly higher than EVA, TPU midsole. Conclusion : TPU midsole can reduce the load on the midfoot effectively and activate tibialis anterior, biceps femoris to give help to running.

• 한국운동역학회지
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• 제25권1호
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• pp.29-37
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• 2015

Objective : The purpose of this study was to investigate the biomechanical properties of shock absorption strategy and postural stability during the drop landing for each types. Methods : The motions were captured with Vicon Motion Capture System, with the fourteen infra-red cameras (100Hz) and synchronized with GRF(ground reaction force) data(1000Hz). Ten male soccer players performed a drop landing with single-leg and bi-legs on the 30cm height box. Dependent variables were the CoM trajectory and the Joint Moment. Statistical computations were performed using the paired t-test and ANOVA with Turkey HSD as post-hoc. Results : The dominant leg was confirmed to show a significant difference between the left leg and right leg as the inverted pendulum model during Drop Landing(Phase 1 & Phase 2). One-leg drop landing type had the higher CoM displacement, the peak of joint moment with the shock absorption than Bi-leg landing type. As a lower extremity joint kinetics analysis, the knee joint showed a function of shock absorption in the anterior-posterior, and the hip joint showed a function of the stability and shock absorption in the medial-lateral directions. Conclusion : These findings indicate that the instant equilibrium of posture balance(phase 1) was assessed by the passive phase as Class 1 leverage on the effect of the stability of shock absorption(phase 2) assessed by the active phase on the effect of Class 2 leverage. Application : This study shows that the cause of musculo-skeletal injuries estimated to be focused on the passive phase of landing and this findings could help the prevention of lower damage from loads involving landing related to the game of sports.

• 대한치과교정학회지
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• 제44권5호
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• pp.246-253
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• 2014

Objective: To evaluate the bioactivity, and the biomechanical and bone-regenerative properties of Ti6Al4V miniscrews subjected to anodization, cyclic precalcification, and heat treatment (APH treatment) and their potential clinical use. Methods: The surfaces of Ti6Al4V alloys were modified by APH treatment. Bioactivity was assessed after immersion in simulated body fluid for 3 days. The hydrophilicity and the roughness of APH-treated surfaces were compared with those of untreated (UT) and anodized and heat-treated (AH) samples. For in vivo tests, 32 miniscrews (16 UT and 16 APH) were inserted into 16 Wistar rats, one UT and one APH-treated miniscrew in either tibia. The miniscrews were extracted after 3 and 6 weeks and their osseointegration (n = 8 for each time point and group) was investigated by surface and histological analyses and removal torque measurements. Results: APH treatment formed a dense surface array of nanotubular TiO2 layer covered with a compact apatite-like film. APH-treated samples showed better bioactivity and biocompatibility compared with UT and AH samples. In vivo, APH-treated miniscrews showed higher removal torque and bone-to-implant contact than did UT miniscrews, after both 3 and 6 weeks (p < 0.05). Also, early deposition of densely mineralized bone around APH-treated miniscrews was observed, implying good bonding to the treated surface. Conclusions: APH treatment enhanced the bioactivity, and the biomechanical and bone regenerative properties of the Ti6Al4V alloy miniscrews. The enhanced initial stability afforded should be valuable in orthodontic applications.

• The Journal of Korean Physical Therapy
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• 제25권5호
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• pp.239-245
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• 2013

Purpose: Osteoarthritis occurs in many different joints of the body, causing pain, stiffness, and decreased function. The knee is the most frequently affected joint of the lower limb. The aim of this study was to investigate the differences of biomechanics between independent gait and anterior walker dependent gait of patients with osteoarthritis of the knee. Methods: Lower limb joint kinematics and kinetics were evaluated in 15 patients with knee osteoarthritis when walking independently and when walking with an anterior walker. Participants were evaluated in a gait laboratory, with self-selected gait speed and natural arm swing. Results: When walking with a dependent anterior walker, participants walked significantly faster (p<0.01), using a longer stride length (p<0.01), compared to independent gait. When walking with a dependent anterior walker, participants exhibited significantly greater knee flexion/extension motion (p<0.01) and lower knee flexion moment (p<0.05) compared to independent gait. When walking with a dependent anterior walker, participants showed significantly greater peak ankle motion (p<0.01), ankle dorsiflexion/plantarflexion moments (p<0.01), and ankle power generation (p<0.05) compared to independent gait. Conclusion: These biomechanical properties of gait, observed when participants walked with a dependent anterior walker, may be a compensatory response to impaired knee function to allow sufficient power generation for propulsion. Therefore, rehabilitative strategies for patients with osteoarthritis of the knee are needed in order to improve not only knee function but also hip and ankle function.