• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.9
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• pp.1145-1151
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• 2010

In this paper, we discuss the design and simulation of a jumping-robot mechanism that is actuated by SMA (shape memory alloy) wires. We propose a jumping-robot mechanism; the structure of the robot is inspired by the musculoskeletal system of vertebrates, including humans. Each robot leg consists of three parts (a thigh, shank, and foot) and three kinds of muscles (gluteus maximus, rectus femoris, and gastrocnemius). The jumping capability of the robot model was tested by means of computer simulations, and it was found that the robot can jump to about four times its own height. This robot model was also compared with another model with a simpler structure, and the performance of the former, which was based on the biomimetic design, was 3.3 times better than that of the latter in terms of the jumping height. The simulation results also verified that SMA wires can be suitable actuators for small jumping robots.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.8 no.1
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• pp.75-85
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• 2013

Objectives: The purpose of this case report is to investigate the effect of exercise for vastus medialis to knee pain patients with patello-femoral pain syndrome. Methods: Two patients with patello-femoral pain syndrome were treated by exercise for vastus medialis. To measure the outcome of the patients' improvement, we observed the X-ray of both knee sky-line view, Numerical Rating Scale(NRS), and Western Ontario and McMaster Universities(WOMAC) index. Results: After being treated by exercise for vastus medialis, the patients' X-ray of both knee sky-line view, Numerical Rating Scale(NRS), and Western Ontario and McMaster Universities(WOMAC) index were significantly improved. Conclusions: These results suggest that exercise for vastus medialis is effective treatment to patients with patello-femoral pain syndrome.

• The Journal of the Korean bone and joint tumor society
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• v.13 no.2
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• pp.185-189
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• 2007

Advancement of imaging and surgical technique makes the internal hemipelvectomy one of the routine procedures of pelvis sarcoma. However, optimal reconstructive option for skeletal defect is still controversial. Pasteurized autogenous bone-total hip composite is a biologic method and its anatomical appropriateness gives good indication for selected cases. Nevertheless, in case of complication such as infection or mechanical breakage, removal of hardware including graft is inevitable. In those cases, marked limb length discrepancy induce marked functional deficit. To overcome this problem, the authors report 1 case, refining previous technique, saving the femoral head and reinsertion of osteoarticularly pasteurized host bone.

• Journal of the Korean Orthopaedic Association
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• v.55 no.3
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• pp.276-280
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• 2020

A 49-year-old male was found unconscious at his accommodation and visited the emergency room. He was on antipsychotic and antidepressant drugs (vortioxetine hydrobromide, mirtazapine, sertraline hydrochloride, quetiapine, and alprazolam) for schizophrenia and major depression. At the time of discovery there were signs of overdose of the drugs around the patient. A physical examination revealed, pain, pallor, and edema in the left buttocks and lateral thigh. Active ankle movements below the left ankle were not possible and sensations in the tibia and peroneal nerves were lost. The pressure in the buttock compartment was measured at 42 mmHg. Magnetic resonance imaging revealed edema and high intensity signals in the left hip muscles and surrounding soft tissue. An emergency fasciotomy was performed and partial restoration of the lower extremity sensation and muscle strength were achieved after 24 hours.

• The Journal of the Korean bone and joint tumor society
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• v.11 no.2
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• pp.175-182
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• 2005

Purpose: Bone tumor occurred in femur frequently involve proximal intertrochanteric region or distal metaphyseal region. Sometimes, the pathologic fracture can happen according to the size of tumor due to the substantial biomechanical stresses. Therefore, the prognosis can be improved biomechanically by the angled blade plate considering the anatomic configuration after the excision of tumor. Materials and Methods: Between October 1991 and April 2005, there were a total of 16 patients(17 cases) who were treated by the excision of tumor and internal fixation with the angled blade plate for bone tumor occurred in femur. After the excision of tumor, we filled the cavity by bone graft in 11 cases and bone cement in 6 cases. The internal fixation was used by angled blade plate in all cases. Result: The average follow-up time was 55.5 months(6-144 months) in 16 patients(17 cases). No metal failure occurred after the operation. Reoperation was performed in 4 cases due to tumor recurrence, and the internal fixation was firm until that. Conclusion: The angled blade plate can prevent the fracture until grafted bone incorporated to host bone, and protect fragile connection between cement and host bone.

• The Journal of the Korean bone and joint tumor society
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• v.14 no.2
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• pp.119-124
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• 2008

Purpose: To present our experience with soft tissue reconstruction using anterolateral thigh free flap after resection of soft tissue sarcoma. Materials and Methods: Between January of 2003 and June of 2007, we treated 7 patients with soft tissue reconstruction using anterolateral thigh free flap after wide resection for soft tissue sarcoma. We retrospectively analyzed type and size of tumors, resection margin, size of defect after resection, time of operation, flap survival and complication. Results: The type of sarcoma was 3 synovial sarcoma, 2 malignant fibrous histiocytoma, 1 leimyosarcoma and 1 fibrosarcoma. The size of tumor varied from $3{\times}5\;cm$ to $7{\times}8\;cm$. The resection margins of tumors were negative in all cases. The size of soft tissue defect after resection varied from $6{\times}8\;cm$ to $15{\times}10\;cm$. The mean time of operation was 3.6 hours. All flaps were survived. Conclusion: Anterolateral thigh free flap appear to be ideal for reconstruction after wide resection of soft tissue sarcoma.

• The Journal of the Korean bone and joint tumor society
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• v.5 no.1
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• pp.70-75
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• 1999

We present a case of parosteal osteosarcoma of the femur with secondary dedifferentiation. This 57-year-old woman was radiologically diagnosed as a parosteal osteosarcoma in 1987. In 1992, excisional biopsy revealed a classical parosteal osteosarcoma with diploidy DNA pattern. In 1998, she revisited due to a recurrent tumor with pathologic fracture. The resected specimen showed a classic parosteal osteosarcoma with area of dedifferentiation, showing high-grade spindle cell sarcoma. This dedifferentiated area revealed aneuploidy cell population on DNA flow cytometry. This case reminds us that not all parosteal osteosarcomas are low-grade lesions. Some low-grade lesions may dedifferentiate to become high-grade tumors after inadequate excision.

• The Journal of the Korean bone and joint tumor society
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• v.12 no.1
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• pp.83-88
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• 2006

Osteochondroma is a hyperplasic bony lesion caused by subperiosteal displacement of physeal cartilages, and the most common benign bone tumor. Osteochondromas rarely cause vascular complications, but when encountered, acute ischemia, phlebitis, and arterial puncture are the most common. They are caused by the mass effect or by the sharp end of the tumor. Deep vein thrombosis may be caused by impaired venous blood flow or a hypercoagulable blood state, but sometimes no predisposing cause can be found. We experienced a patient with deep vein thrombosis caused by the mass effect of an asymptomatic osteochondroma, and treated him successfully by excising the osteochondroma and performing a saphenous vein graft after resecting obstructed vein.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.10
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• pp.2317-2323
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• 2010

When the muscle is contracted by continuous and same, the force takes fatigue and stiffness. The aim of this study was to know how the fatigue and muscle stiffness change during an isometric contraction. Surface Electro myography(EMG) signal monitoring system and ultrasonic transducer set up the same muscle stem, subjects contract his right femoris muscle by submaximal isometric contraction(50% of MVC) until exhaustion. Before and after the test, muscle stiffness was measured and EMG was measured during the contraction. As time goes by, muscle fatigue was increased. and the stiffness was shown strongly after the contraction. These results show if the muscle becomes more and more fatigued, the circulation of muscle is delayed although the contraction doesn't happen. So muscle stiffness is increased.

• The Journal of the Korean bone and joint tumor society
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• v.15 no.2
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• pp.178-183
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• 2009

Angiosarcoma is a very rare disease of soft tissue sarcoma, and angiosarcoma arising in a region of chronic lymphedema is referred to as Stewart-Treves syndrome. it typically occurs in postmastectomy lymphedema of the arm and sporadically in a lymphedematous leg. The prognosis, even with wide surgical excision and subsequent radiotherapy, is poor. The authors experienced a case of angiosarcoma in a chronically lymphedematous leg which had undergone hysterectomy due to cervical cancer 17 years ago and lymphedema of leg persists for about 16 years. We report a case of angiosarcoma with a brief review of the literature.