• 대한기계학회논문집A
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• 제24권11호
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• pp.2777-2785
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• 2000

In cementless total hip replacement(THR), an initial stability of the femoral component is important to long term fixation of femoral stem. The intial stability has close relationship with the relative displacement of prosthessis and sponge bone at the proximal of femur. After implantation of the proshesis, the surrounding bone is partially shielded from load carrying and starts to resorb. Stress shielding is the cause of the loss of proximal bone. Assessing stress distribution of femur is important to predict stress shielding. The initial stability and the stress shielding were investigated for two loading conditions approximating a single leg stance and a stair climbing. Three types of stems were studied by the finite element method to analyze the biomechanical effects of distal filling of cementless femoral stems. Three types of stems empolyed are a distal filling stem, a distal flexible stem, and a distal tapered stem.

• The Journal of Korean Physical Therapy
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• 제11권1호
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• pp.63-70
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• 1999

This study was for mathematical method of calculating the joint reaction force during on single - leg stance on a normal and hemiplegic patients. It is important to compare the distance of the line of gravity from the hip joint on hemiplegic patients with this on normal in this study. In earlier studies, there is no include the concept about biomechanical analysis on the shin of line of gravity of hemiplegic patients. Though this concept, we found the compensation make the line of gravity closer to the supporting hip joint and the trunk was toward the side of paralysis. The result of the Joint reaction force on hemiplegic patients is found to be approximately $31.33\%$ in the unaffected side by biomechanical analysis.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.387-392
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• 2000

In cementless total hip replacement(THR), an initial stability of the femoral component is important to long term fixation of femoral stem. The initial stability has close relationship with the relative displacement of prosthesis and spongy bone at the proximal of femur. After implantation of the prosthesis. the surrounding bone is partially shielded from load carrying and starts to resort. Stress shielding is the cause of the loss of proximal bone. Assessing stress distribution of femur is important to predict stress shielding. The initial stability and the stress shielding were investigated for two loading conditions approximating a single leg stance and a stair climbing. Three types of stems were studied by the finite element method to analyze the biomechanical effects of distal filling of cementless femoral stems, Three types of stems employed are a distal filling stem, a distal flexible stem, and a distal tapered stem.

• 대한물리의학회지
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• 제15권4호
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• pp.37-45
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• 2020

PURPOSE: The purpose of this study was to identify the effects of neck stabilization exercise combined with trunk stabilization exercise on balance and gait function in patients with chronic stroke. METHODS: Twenty-two chronic stroke patients were included in this study. The experimental group subjects (n = 11) performed neck stabilization (15 min) and trunk stabilization (15 min) exercises, while the control group subjects (n = 11) performed trunk stabilization exercise only for 30 min. Before and after the intervention, the subjects underwent static balance and gait testing. RESULTS: The 95% confidence ellipse area, center of pressure (COP) path length, and COP average velocity were significantly lower in both groups after the intervention compared to before intervention (p < .05). The average stance force on the affected side increased significantly in both groups after the intervention (p < .05). The changes in the static balance variables were larger in the experimental group than in the control group. The cadence, gait velocity, and single leg support increased significantly in both groups after intervention (p < .05). The changes in the gait variables were larger in the experimental group than in the control group. CONCLUSION: Trunk stabilization is a beneficial intervention, but the combination of neck stabilization with trunk stabilization is a more effective method to increase the gait and static balance in chronic stroke patients.

• 대한임상검사과학회지
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• 제52권1호
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• pp.36-44
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• 2020

With the advent of westernized diet and a lack of exercise, young female college students are paying more attention to their bodyweight and health. Whole-body vibration has been demonstrated to be a suitable training method for improving knee extension maximal strength in young female athletes, as well as the gait performance in elderly women. This study aimed to evaluate the effects of a vertical vibration intervention on the physical fitness and postural balance in young females. Fifty-four young women were recruited; all subjects were randomly assigned to the intervention group and control group. The intervention group underwent vertical vibration with a platform for 12 weeks. The results showed that body mass index and body fat percentage had decreased (P<0.05). In addition, their muscle endurance as indicated by a sit-up test and their flexibility as indicated by a sit-and-reach test were both increased. With regard to postural balance, their 30-second sit-to-stand and timed up and go test results were improved. At the same time, their mean single-leg stance with eyes closed time increased (P<0.05). However, there were no significant differences, meanwhile, for the control group. Overall, the results showed that the whole body vibration (WBV) intervention had some beneficial effects on physical fitness and postural balance in young women.

• 웰빙융합연구
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• 제5권1호
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• pp.1-7
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• 2022

Purpose: This study aimed to investigate spatial and temporal features of motor control in an individual with hemiparesis during the curvilinear gait (CG) and proposed an exercise guideline. Research design, data and methodology: An individual aged 63 with hemiparesis by stroke disease was participated in the study. Autoencoder (AE) was used to extract four motor modules from eight muscle activities of the paretic leg during CG. After extraction, each module of four modules was operationally defined by numbering from M1 to M4 according to spatial and temporal features and compared with results reported in a previous study. Results: As a result, an individual with hemiparesis had motor module problems related to difficulty of weight acceptance (module 1), compensation for the weakness of ankle plantar flexor (module 2), a spastic synergistic pattern (module 3) and difficulty with transition from the swing to stance phase (module 4) in terms of spatial features. Also, a delayed activation timing of temporal motor module (module 2) related to the forward propulsion during CG was observed. Conclusions: Gait rehabilitation for the stroke will need to consider clinical significances in respect of the deterioration of motor module and provide the tailored approaches for each gait phase.

• Physical Therapy Rehabilitation Science
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• 제11권4호
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• pp.517-525
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• 2022

Objective: The rehabilitation protocols for functional recovery have been emphasized after total knee arthroplasty, and Pilates is in the spotlight as a safe and easily modified exercise method. The purpose of this study was to investigate the effects of mat Pilates exercise on lower extremity function, postural balance, and walking in the individuals with total knee arthroplasty. Design: One group pretest-posttest design. Methods: Eighteen older women with unilateral total knee arthroplasty was recruited in the study. The subjects were evaluated on lower extremity function, postural balance, and walking before and after mat Pilates exercise. All subject performed one hour mat Pilates exercise, 3 times a week for 8 weeks. Mat Pilates exercises were focused on core stability and lower extremity strengthening and, more dynamic movements were added to increase the difficulty of movements every two weeks. The lower extremity function was measured using the Western Ontario and McMaster Osteoarthritis Index (WOMAC), knee joint position sense, and five times sit-to-stand test. Postural balance was assessed by single leg stance test, functional reach test, and timed up and go test. Walking was measured by OptoGait system to temporospatial parameter. Results: The lower extremity function, postural balance, and walking were significantly improved after mat Pilates exercise, except for five times sit-to-stand test (p<0.05). Conclusions: This study demonstrated that the mat Pilates exercise was a useful method to improve lower extremity function, postural balance, and walking in the older women with unilateral total knee arthroplasty.

• 대한의료기공학회지
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• 제21권1호
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• pp.22-42
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• 2022

Objective : The researcher participated in the visiting treatment project organized by OO City in 2020 and showed the advantages of visiting Korean Medicine, so I would like to report it. Methods : A comprehensive Korean Medicine intervention method was performed for each symptom, and changes in basic physical strength were observed through vital signs, NRS, Single Leg Stance (SLS), and Chair Stand Test (CST) tests. Results : It can be seen that the NRS level, a pain scale for chronic pain, generally decreased at the last treatment compared to the beginning of treatment. Satisfaction with Project Information (PI) was relatively low at 3.20±1.30, but Ease of Participation (EoP), Intention to Participate Again (IPA), Expansion of Project (ExP), and Overall Satisfaction (OS) were high at 5.00±0.00. Conclusions : Summarizing the advantages of visiting Korean Medicine is that the treatment satisfaction for chronic pain is high, the patient's satisfaction is high, the treatment tool is easy to carry, and various visiting treatment services can be implemented.

• 한국체육학회지인문사회과학편
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• 제58권6호
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• pp.449-459
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• 2019

이 연구의 목적은 외발서기 동작 시 취득한 운동역학데이터로부터 주파수분석의 기법을 통하여 인체 운동명령신호가 어떻게 자세조절 과정에 영향을 미치는지를 규명하는 자세역학의 토대연구이다. 이를 위하여 체조경력 10년 이상의 운동신경이 우수한 국가대표상비군(n=6)과 일반인(n=6)을 대상으로 발바닥 압력중심점(CoP)의 궤적데이터를 FFT신호처리기법에 의한 저주파대역Rambling (RM)과 고주파대역 Trembling (TR)의 주파수분석을 탐색하였다. 본 연구결과에 따르면 눈뜨고 외발서기와 눈감고 외발서기 동작을 중심으로 두 집단 간 자세조절능력의 안정화지수 평가에서 독립표본 t검증에서 유의한 차이가 나타났으며(p<.05), 이러한 차이는 저주파대역 RM의 주요주파수 f1과 고주파대역 TR의 주요 주파수 f2의 최대진폭의 출력 차이로 밝혀졌다(p<.05). 특히 자세송환피드백에 관여하는 고유주파수인 저주파수대역에서는 주요주파수가 8-9 Hz 대역에서 뇌지시 하 안정적 자세조절의 운동기전을 행하는 운동명령으로 확인하였으며, 120-135 Hz의 고주파수대역에서는 자세 흔들림을 최소화하기 위한 반사적 근반응의 적응성을 보이는 것으로 연구되었다. 자세조절의 중추신경계 운동조절에 관여하는 고유주파수와 최대진폭에서 유의한 차이가 발견됨으로서 외발서기 시 발바닥 압력조절에 의한 신호파형의 운동명령이 자세조절에 영향을 미치는 것으로 해석되었다.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1994년도 추계학술대회
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• pp.71-74
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• 1994

In cementless total hip arthroplasty(THA), an initial stability of the femoral component is mandatory to achieve bony ingrowth and secondary long term fixation. Bone ingrowth depends strongly on relative micromotion and stress distributions at the interface. Primary stability of the femoral component can be obtained by minimizing the magnitude of relative micromotions at bone-prosthesis interface, Hence an accurate evaluation of interface behavior and stress/strain fields in the bone implant system may be relevant for better understanding of clinical situations and improving THA design. However, complete evaluation of load transfer in the bone remains difficult to assess experimentally, Hence, recently finite element method (FEM) was introduced in orthopaedic research field to fill the gap due to its unique capacity to evaluate stress in structure of complex shape, loading and material behavior. The authors developed the 3-dimensional numerical finite element model which is composed of totally 1179 elements off and 8 node blick. We also analyzed the micromotions at the bone-stem interface and mechanical behavior of existing bone prosthesis for a loading condition simulating the single leg stance. The result indicates that the values of relative motion for this well fit Multilock stem were $150{\mu}m$ in maximum, $82{\mu}m$ in minimum, and the largest relative motion developed in medial region of proximal femur with anterior-posterior direction. The proximal region of the bone was much larger in motion than the distal region and the stress pattern shows high stress concentration on the cortex near the tip of the stem. These findings indicates that the loading in the proximal femoral bone in the early postoperative situation can produce micromotions on the interface and clinically cementless TEA patient should not be allowed weight bearing strictly early in the postoperative period.