• 한국전문물리치료학회지
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• 제13권4호
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• pp.71-78
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• 2006

This study examined the effects of socket flexion angle in trans-tibial prosthesis on stump/socket interface pressure. Ten trans-tibial amputees voluntarily participated in this study. F-socket system was used to measure static and dynamic pressure in stump/socket interface. The pressure was measured at anterior area (proximal, middle, and distal) and posterior area (proximal, middle, and distal) in different socket flexion angles ($5^{\circ}$, $0^{\circ}$, and $10^{\circ}$). Paired t-test was used to compare pressure differences in conventional socket flexion angle of $5^{\circ}$ with pressures in socket flexion angles of $0^{\circ}$ and $10^{\circ}$ (${\alpha}$=.05). Mean pressure during standing in socket flexion angle of $10^{\circ}$ decreased significantly in anterior middle area (19.7%), posterior proximal area (10.4%), and posterior distal area (16.3%) compared with socket flexion angle of $5^{\circ}$. Mean pressure during stance phase in socket flexion angle of $0^{\circ}$ increased significantly in anterior proximal area (19.3%) and decreased significantly in anterior distal area (19.7%) compared with socket flexion angle of $5^{\circ}$. Mean pressure during stance phase in socket flexion angle of $10^{\circ}$ decreased significantly in anterior proximal area (19.6%) and increased significantly in anterior distal area (8.2%) compared with socket flexion angle of $5^{\circ}$. Peak pressure during gait in socket flexion angle of $0^{\circ}$ increased significantly in anterior proximal area (23.0%) compared with socket flexion angle of $5^{\circ}$ and peak pressure during gait in socket flexion angle of $10^{\circ}$ decreased significantly in anterior proximal area (22.7%) compared with socket flexion angle of $5^{\circ}$. Mean pressure over 80% of peak pressure ($MP_{80+}$) during gait in socket flexion angle of $0^{\circ}$ increased significantly in anterior proximal area (23.9%) and decreased significantly in anterior distal area (22.5%) compared with socket flexion angle of $5^{\circ}$. $MP_{80+}$ during gait in socket flexion angle of $10^{\circ}$ decreased significantly in anterior distal area (34.1%) compared with socket flexion angle of $5^{\circ}$. Asymmetrical pressure change patterns in socket flexion angle of $0^{\circ}$ and $10^{\circ}$ were revealed in anterior proximal and distal region compared with socket flexion angle of $5^{\circ}$. To provide comfortable and safe socket for trans-tibial amputee, socket flexion angle must be considered.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.1070-1073
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• 2002

The biomechanical interaction between the stump and the prosthetic socket is critically important to achieve close-to-normal ambulation. Many investigators suggested that the pressure changes during gait of transfemoral amputees are closely related to the prosthetic alignment, the socket shape, the stump size, and the residual muscle activity. The effects of the prosthetic alignment, the socket shape, and the stump size on the interface pressure were investigated previously. However, there is no report how the residual muscle activities in the transfemoral stump affect the socket interface pressure characteristics during gait. Since designs of socket fur lower limb amputees need to consider the socket interface pressure characteristics, the interface pressure patterns by the residual muscle activities during gait should be investigated. In this study, myoelectric signals (MES) and socket interface pressure in residual limb of transfemoral amputees were measured during the stance and swing phases of gait. For the purpose, specially designed quadrilateral sockets that MES electrodes could be instrumented were fabricated. A total of two transfemoral amputees were participated in the experiments. The measured temporal MES amplitude and interface pressure in knee flexor (biceps femoris) and extensor (rectus femoris) had significant correlations (P ＜ 0.05). Based on the test results, It was suggested that the residual muscle activity of transfemoral amputees stump is an important factor affecting socket pressure changes during walk.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 춘계학술대회
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• pp.249-252
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• 1997

A study on static and dynamic socket pressure distributions on a trans-femoral amputee with a suction socket was performed in order to assess an optimal socket fitting and function. Even for the amputee's static neutral position, pressure concentrations were observed in the lateral, medial, and posterior planes of the socket. During free walking, a significant movement of pressure concentration areas was observed. Large socket pressure was observed in the lateral, medial-anterior and posterior walls during mid-stance or push-off period. Socket pressure measurement will be one of the good tool to determine the optimal socket-limb interface.

• 대한의용생체공학회:의공학회지
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• 제19권4호
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• pp.417-422
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• 1998

본 연구는 대퇴의족착용자의 정적중립상태 및 자유보행시에 단단부와 소케의 경계에 작용하는 압력 분포를 측정하였다. 정적중립상태에서는 단단부의 외측과 내측면과 후면에서 압력집중현상이 나타나고, 자유보행시는 이러한 압력집중이 보행중에 일정한 형태로 이동함을 알 수 있었다. 최대 소켓압력은 중간입각기나 발뒤축들림기에 외측, 내측 앞쪽, 후면에서 나타나고 있고, 소켓과 단단부 사이의 상태를 확인하는 방법중 하나로 소켓 압력 측정을 사용할 수가 있다.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 추계학술대회
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• pp.369-372
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• 1997

Socket pressure distributions with gait analyses of a transfemoral and a transtibial prostheses were measured in order to assess an optimal socket fitting and unction. Ankle joint was aligned by the neutral and the dorsi/plantar flexed positions. Compared to dorsi and plantar flexed positions of ankle joint, cadence and walking speed increased with the neutral ankle joint alignment. Other gait parameters were close to the normative data with the neutral ankle joint alignment. For the transfemoral amputee, dorsiflexed alignment of the ankle joint created high pressure on the lateral aspect of the socket, on the other hand, plantarflexed alignment resulted in increased pressure on the medial aspect of the socket. For the transtibial amputee, dorsiflexed alignment of the ankle resulted in high pressure on the antero-lateral aspect of the socket during mid-stance, but plantarflexion of the ankle joint showed slight increases in pressure at the same location in the socket. The present study clearly demonstrated that malalignment of a prosthesis results in localized increasing pressure within the socket. Proper alignment of the prosthesis is required in order to acquire an appropriate socket-limb interface as well as the proper gait.

• 대한기계학회논문집A
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• 제30권11호
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• pp.1433-1438
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• 2006

A systematic approach to socket shape design of a concave piston assembly for a high pressure hydraulic pump of an excavator is presented in this paper. A design model is given and a methodology of socket shape design is proposed. An axisymmetric rigid-plastic finite element method is employed for predicting the approximate socket shape formed by a rotary forming process as well as for simulating the test process for separating the shoe from the piston assembly designed. It is verified that the predictions are in good agreement with the experiments. The approach is successfully applied to developing an optimal concave piston assembly.

• 대한의용생체공학회:의공학회지
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• 제19권4호
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• pp.403-416
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• 1998

본 연구는 대퇴 및 하퇴 의족 착용자의 소켓의 적합성 및 기능성을 평가하기 위하여 소켓내부압력을 측정하였다. 발목관절을 중립, 배굴, 저굴 상태로 조절하였을 때, 배굴 및 저굴에 비하여 중립상태에서 분속수나 보행속도는 증가 하였다. 다른 보행 인자들 역시 발목관절을 중립상태로 조절하였을 때 정상인의 보행인자에 근접하고 있다. 대퇴 절단 환자의 경우 발목관절을 배굴 상태로 조절하면 소켓의 외측부분에 압력집중이 나타나고, 저굴상태로 조절하면 소켓의 내측 부분에 압력집중이 발생하였다. 하퇴 절단 환자의 경우 발목관절을 배굴상태로 조절하면 중간입각기때 소켓의 전면 외측에 압력집중 현상이 나타나며, 저굴시에는 배굴시와 같은 위치에 약간의 압력이 증가하는 것으로 나타났다. 본 연구는 의족의 부적절한 정렬상태로 인한 소켓내에서의 압력집중 현상을 설명하고자 하였으며, 의족의 올바른 정렬은 적절한 보행을 유도하기 위한 소켓과 스텀프와의 접촉 상태를 결정하는데 있어 매우 중요한 인자중 하나이다.

• Corrosion Science and Technology
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• 제3권5호
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• pp.216-221
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• 2004

The operating experience showed that the fatigue is one of the major piping failure mechanisms in nuclear power plants (NPPs). The pressure and/or temperature loading transients, the vibration, and the mechanical cyclic loading during the plant operation may induce the fatigue failure in the nuclear piping. Recently, many fatigue piping failure occurred at the socket weld area have been widely reported. Many failure cases showed that the gap requirement between the pipe and fitting in the socket weld was not satisfied though the ASME Code Sec. III requires 1/16 inch gap in the socket weld. The ASME Code OM also limits the vibration level of the piping system, but some failure cases showed the limitation was not satisfied during the plant operation. In this paper, the fatigue behavior of the socket weld in the nuclear piping was estimated by using the three dimensional finite element method. The results are as follows. (1) The socket weld is susceptible to the vibration if the vibration levels exceed the requirement in the ASME Code OM. (2) The effect of the pressure or temperature transient load on the socket weld in NPPs is not significant because of the very low frequency of the transient during the plant lifetime operation. (3) 'No gap' is very risky to the socket weld integrity for the specific systems having the vibration condition to exceed the requirement in the ASME OM Code and/or the transient loading condition. (4) The reduction of the weld leg size from $1.09*t_1$ to $0.75*t_1$ can affect severely on the socket weld integrity.

• 전기전자학회논문지
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• 제26권2호
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• pp.249-256
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• 2022

대퇴의족은 절단하지를 대체하여 보행을 수행하는 기기이며, 불연속적으로 변하는 보행 환경에 대응하기 위해 사용자의 의도 제공을 통한 보행 모드 변경을 요구한다. 외부의 제어 기기 없는 자연스러운 보행 모드 변경을 위한 요구로 절단 부위와 직접 접촉하는 소켓 내부의 생체 역학적 특징을 통해 사용자의 의도를 검출하는 연구가 수행되어 왔다. 하지만 아직까지 절단 부위의 신체 및 소켓 내부 환경에 적합한 센서 시스템의 요구가 남아있다. 따라서 본 연구에서는 절단 부위의 신체 특성에 적합하고 소켓 내부 온습도 조건에 영향을 받지 않으며 다양한 크기의 제작이 쉬운 필름 형태의 센서 시스템을 제안하였다. 제안된 센서는 Velostat 필름으로 제작되었으며 크기에 따라 달라지는 압력 계측 특성이 고려되었다. 실험을 통해 착용자의 의도적인 자세 수행에 의한 소켓 내부 압력 변화를 계측하였으며 보행 모드 변경 의도 검출의 가능성을 확인하였다.

• 대한장애인치과학회지
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• 제8권1호
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• pp.15-21
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• 2012

Extraction of all nonrestorable teeth prior to bone marrow transplantation is the major dental management of the patient being prepared for the transplantation. But, there are four principal causes for excessive bleeding in the immediate postextraction phase ; (1) Vascular wall alteration (wound infection, scurvy, chemicals, allergy) (2) Disorders of platelet function (3) Thrombocytopenic purpuras (4) Disorders of coagulation (liver disease, anticoagulation drug-heparin, coumarin, aspirin, plavix) If the hemorrhage from postextraction wound is unusually aggressive, the socket must be packed with local hemostatic agent and wound closure & pressure dressing are applied. But, in dental alveoli, local hemostatic agent (gelfoam, surgcel etc) may absorb oral microorganisms and cause alveolar osteitis (infection). This is a case report of bleeding and infection control by suture, pressure packing and iodoform gauze drainage on infected active bleeding extraction socket under sedation and local anesthesia in a 57-years-old multiple disabled patient with anticoagulation drug.