• 대한족부족관절학회지
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• 제13권2호
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• pp.133-137
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• 2009

Purpose: The purpose of this study was to evaluate the clinical results of the old Achilles tendon rupture treated with modified flexor hallucis longus (FHL) tendon transfer. Materials and Methods: Seventeen patients with old Achilles tendon rupture treated with modified FHL tendon transfer between March 2004 and February 2008 were enrolled in this study. Technically FHL was pass through the distal portion of the ruptured tendon instead of the drilled hole made on the calcaneus. The mean age of the patients was 37 years (range, 22~67 years), mean follow-up period was 28 months (range, 12~30 months). Patients' subjective satisfaction, calf circumferential diameter, range of motion of ankle and AOFAS ankle-hind foot score and Arner-Lidholm score was evaluated. Results: The average gap between the ruptured tendon was 52 mm (range, 47~56 mm). The AOFAS score improved from 47 pre-operatively to 91 points at the last follow-up. Sixteen patients were satisfied with the result free from discomfort, a patient had mild discomfort who had DM. fourteen patients had decreased range of motion less than 5 degrees while 2 patients had more than 7 degrees decrease compared to the intact side but had no discomfort in daily activities. Nine patients had less than 1 cm calf circumferential diameter difference and 7 patients had 1 to 3 cm diameter difference compared to the intact side. One who had more than 3 cm diameter difference had deteriorated muscle strength. Conclusion: Modified FHL tendon transfer can be a useful technique for the treatment of old Achilles tendon rupture when the gap is with large gap placed too proximal.

• 콘크리트학회논문집
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• 제14권6호
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• pp.843-850
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• 2002

프리스트레스트 콘크리트 부재의 해석이론에서 텐던의 직선이동(linear transformation)은 텐던 배치에 대한 해석을 간략화시켜주는 장점이 있어 빈번히 다루어지고 있다. 본 논문은 그동안 간과되기 쉬웠던 직선이동에 내재된 근사화 및 그 영향을 밝히는데 중점을 두고 있으며, 주로 등가하중법(equivalent load method)을 통하여 직선이동의 이론을 분석하였다. 텐던이 이동하더라도 똑같은 등가하중 시스템이 산출되는 것을 직선이동으로 볼 경우, 기존의 등가하중법 고유의 내재된 가정은 그러한 직선이동의 원리가 성립하도록 하고 있으며, 반면 근사화가 포함되지 않은 엄밀한 의미의 등가하중 시스템에서는 그러한 원리가 성립하고 있지 않다 또한, 자체평형의 성질로부터 유도된 등가하중법을 직선이동에 적용하는 방안을 모색하였으며, 기존의 결과와 약간 다른 등가하중 시스템을 산출하였다. 논의를 확장하여 격납구조물 벽체 원환텐던(circumferential tendon)의 편심배치 문제를 직선이동의 관점에서 분석하였다.

• Archives of Plastic Surgery
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• 제32권4호
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• pp.539-542
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• 2005

Reconstructions of soft tissue defect of the posterior ankle including Achilles the tendon should take into account not only coverage but functional outcome. Various methods of tendon transfer and tendon graft have been reported as a single-stage procedure. With advances and refinements in microsurgical techniques, several free composite flaps including tendon, fascia, or nerve have been used in single-stage reconstructions of large defects in this area minimizing further damage to the traumatized leg. However, when free flap is not feasible for some reasons, this cannot be accomplished successfully. Here we present a patient with Achilles tendon and circumferential large soft tissue defect. Because of circulatory compromise of the lower extremity, free flap reconstruction could not be applied. Instead, cross-leg composite flap of the dorsalis pedis flap including the extensor hallucis brevis musle and tendon, and tendon strips of the Second, third and fourth extensor digitorum logus were employed, Functional reconstruction of the tendon and resurfacing were obtained at the same time. The flap was detached 3 weeks postoperatively, and the transplanted flap has survived without any complications. By 3 months after surgery, full weight bearing, tip-toe standing and even walking without crutch assistance was possible. When functional reconstruction with the free flap is unattainable in the large defect of the posterior ankle including the Achilles tendon, cross-leg composite island flap of dorsalis pedis flap and tendon strips of the extensor digitorum longus tendon is a viable alternative.

• Smart Structures and Systems
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• 제16권3호
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• pp.415-433
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• 2015

Tendon failures in bonded post-tensioned bridges over the last two decades have motivated ongoing investigations on various aspects of unbonded tendons and their monitoring methods. Recent research shows that change of strain distribution in anchor heads can be useful in detecting wire breakage in unbonded construction. Based on this strain variation, this paper develops a damage detection model that enables an automated tendon monitoring system to identify and locate wire breaks. The first part of this paper presents an experimental program conducted to study the strain variation in anchor heads by generating wire breaks using a mechanical device. The program comprised three sets of tests with fully populated 19-strand anchor head and evaluated the levels of strain variation with number of wire breaks in different strands. The sensitivity of strain variation with wire breaks in circumferential and radial directions of anchor head in addition to the axial direction (parallel to the strand) were investigated and the measured axial strains were found to be the most sensitive. The second part of the paper focuses on formulating the wire breakage detection framework. A finite element model of the anchorage assembly was created to demonstrate the algorithm as well as to investigate the asymmetric strain distribution observed in experimental results. In addition, as almost inevitably encountered during tendon stressing, the effects of differential wedge seating on the proposed model have been analyzed. A sensitivity analysis has been performed at the end to assess the robustness of the model with random measurement errors.

• 콘크리트학회논문집
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• 제14권5호
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• pp.759-765
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• 2002

등가하중법은 프리스트레싱 텐던의 영향을 구조물에 작용하는 외력으로서 고려하는 것으로, 프리스트레싱의 효과를 명확히 하고 해석을 단순화시켜주는 유력한 방법론이다. 본 연구에서는 등가하중법의 관점에서 원형탱크 벽체의 원환텐던 및 수직텐던의 배치가 구조물에 미치는 영향을 이론적으로 분석하였으며, 관련된 설계 시방서에서 규정하고 있지는 않지만 실구조물에서 적지 않은 영향을 미칠 수도 있는 사항들에 대해 고찰하였다. 원환텐던의 편심배치시 텐던의 직선이동의 원리가 성립하므로 어떠한 편심배치에 대해서도 구조거동은 크게 달라지지 않을 것으로 사료된다. 또한, 기존의 수직텐던의 설계 및 해석에 있어서 편심배치에 의한 모멘트 효과를 잘못 산정한 예에 대해 올바른 해석법을 제시하였다. 일반적으로 수직텐던의 편심배치는 구조적으로 큰 효과가 있다고 보기는 힘든 것으로 사료된다. 수직텐던과 관련하여 프와송비의 효과나 절곡부위의 영향이 흔히 간과되어 왔으나, 예제의 분석결과 때로는 원형탱크의 구조거동에 적지 않은 영향을 미칠수도 있다고 판단된다.

• 한국의류산업학회지
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• 제21권4호
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• pp.488-496
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• 2019

This study investigated if the proper pressure level on the wrist tendon area and muscle area of the lower arm are within the same range by examining the responses of blood flow and subjective evaluation. Subjects consisted of 18 males in their 20s, and the experimental bands were custom-made by applying size measurements of each subject. In the experiment, a total of 5 steps were selected by reducing 10 (Step 1) to 50 (Step 5)% from the original body size in the circumferential direction. Blood flow was measured with a sensor attached to the tip of the finger inside the right hand while sitting in a chair for 15 minutes. Blood velocity began to increase (0.82 kPa) when the wrist circumference around tendon area was reduced by 20% (Step 2) and reached its maximum (1.72 kPa) at Step 4. However, the preferred subjective pressure was 1.36 kPa, which was less than the maximum pressure value of 1.72 kPa for Step 4. Blood velocity began to increase when pressure on the muscle area was 1.38 kPa and reached its maximum at 2.16 kPa; however, the most preferred clothing pressure was 1.71 kPa. The results of this study showed that the appropriate pressure level was higher in the muscle area than in the wrist tendon of the lower arm and indicated that graduated compression is favorable.

• 한국정밀공학회지
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• 제30권4호
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• pp.434-441
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• 2013

Bending motion has been used in the surgical instruments with bending structures and tendon mechanisms. A simplified bending angle amplification ratio between the proximal and distal bending joint was derived in this article. The bending structure of disk and rib in the proximal joint was analyzed based on finite element method with an emphasis on the circumferential uniformity of bending stiffness. Regarding the distal joint, optimal design and sensitivity analysis was done with four design variables of outer and inner diameter, rib height and rib width while maximizing the deformation under the stress distribution below the yield stress. Outer diameter and rib width are most critical to maximum deformation as the outer diameter and inner diameters are so to maximum equivalent stress.

• 대한토목학회논문집
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• 제36권6호
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• pp.999-1010
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• 2016

최근 국내에서는 고강도 강연선이 실구조물에 적용되는 사례가 늘어나고 있다. 이 연구에서는 LNG 저장탱크에 통상적으로 적용되는 1,860 MPa급 강연선을 2,400 MPa급 고강도 강연선으로 대체할 때 쉬스 배치 간격 증가에 따른 구조적인 영향을 고찰해 보았다. 먼저, LNG 탱크의 원통형 벽체를 모사하는 유한요소모델에 원환텐던 및 수직텐던의 프리스트레싱 효과를 등가하중으로 가하되 프리스트레싱 효과의 총합은 일정한 상태에서 텐던의 간격 및 긴장력을 조절한 결과, 고강도 강연선을 적용해도 설계 시 요구되는 소정의 응력 분포를 구현할 수 있는 것으로 나타났다. 또한, LNG 탱크 벽체 일부분을 모사하는 실대형 실험체를 제작하고 15.2 mm 직경 고강도 강연선이 31개 삽입된 쉬스를 2개 배치하여 매우 높은 수준의 프리스트레싱 힘이 콘크리트에 적절히 전달되는지 관찰하였다. 한편, 세계 최대 용량인 270,000 kl급 LNG 탱크의 유한요소모델을 구축하고 고강도 강연선을 적용했을 때의 프리스트레싱 효과를 일반 강연선의 경우와 비교하였으며, LNG 누출 사고 시에도 여유압축응력 및 여유압축구간과 같은 수밀성 규정을 만족함을 확인하였다. 이 연구결과는 2,400 MPa급 고강도 강연선이 실제 LNG 탱크에 적용될 때 유용하게 활용될 것으로 기대된다.