• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.26 no.2
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• pp.165-171
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• 2016

A prosthetic knee for above-knee (AK) amputee is categorized into passive and active type. The passive prosthetic knee is generally made by elastic material. Although AK amputee can easily walk by using passive prosthetic leg, knee joint motions are not similar to ordinary persons. The active prosthetic leg can control the knee angle owing to the actuator and microprocessor. However, the active type is not cost-effective and the stability may be lost due to the malfunction of sensors. In order to resolve these disadvantages of passive and active type, a semi-active prosthetic knee which can control the knee angle is proposed in this work. The proposed semi-active one requires a less input energy but provides active type performance. In order to achieve this goal, in this work, a semi-active prosthetic knee using magneto-rheological (MR) damper for AK amputees is designed. The MR damper can support the weight of body by using less energy than actuator of active prosthetic. It can control knee angle by inducing the magnetic field at the time of stance phase. This salient characteristic is evaluated and presented in this work.

• Archives of Plastic Surgery
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• v.40 no.6
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• pp.735-741
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• 2013

Background The prosthetic dura is an essential element in the protection of the cranial parenchyma and prevention of cerebrospinal fluid leakage. Although prosthetic dura are widely used in neurosurgery, they occasionally provoke infection, which can be a major concern after neurosurgical treatment. However, removal of the prosthetic dura carries a risk of brain parenchyma injury and cerebrospinal fluid leakage. The salvage of infected prosthetic dural material has not been adequately addressed in the literature. In this study, we demonstrate the value of the combination of a meticulous surgical debridement of necrotic tissue and simultaneous muscle free flap for intractable postoperative epidural abscess without removal of the infected prosthetic dura. Methods Between 2010 and 2012, we reviewed the data of 11 patients with persistent infection on the prosthetic dura. The epidural infections each occurred after a neurosurgical procedure, and there was soft tissue necrosis with the disclosure of the underlying prosthetic dura and dead bone around the scalp wound. To salvage the infected prosthetic dura, meticulous debridement and a muscle free flap were performed. Results All 11 patients experienced complete recovery from the complicated wound problem without the need for further surgical intervention. No signs of prosthetic dural infection were observed during the mean follow-up period of 11 months. Conclusions The combination of a meticulous surgical debridement and coverage with a muscle free flap is an effective treatment for salvage of infected prosthetic dura.

• Journal of the Institute of Convergence Signal Processing
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• v.19 no.3
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• pp.110-117
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• 2018

The development of prosthetic hand or prosthetic leg equipment is steadily taking place globally. Though it would be difficult to create or feel the same way as a human hand, it would be a great for the amputated person if they can pick things up or do some movement as they want. It has become possible to develop low-cost prosthetic hand according to development of 3D printing technology. If people can develop personalized prosthetic equipment at similar prices to meet this trend, the utilization and penetration rate will be much higher. In this study, it describes how to develop a user-customizable prosthetic hand using 3D printing. To do this, the transformational parameters of prosthetic hand shape modeling are extracted as variability values, and the functions for controlling prosthetic hand motion are designed as software design patterns. This allows people who need a prosthetic hand to have their own prosthetic hand at a fast and affordable price.

• Journal of Chest Surgery
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• v.20 no.4
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• pp.655-658
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• 1987

Aortic annulus size was measured by two-dimensional echocardiography [2DE] in 29 patients undergoing aortic valve replacement or double valve replacement in order to predict prosthetic aortic valve size. Fifteen patients had aortic stenoinsufficiency, eleven had aortic insufficiency, and three had aortic stenosis. 2DE measurements of aortic annulus diameter, as determined from the parasternal long-axis view, demonstrated a high correlation with actual prosthetic valve size implanted at surgery [r=0.85, p<0.05]. 2DE exactly predicted actual prosthetic valve size in 8 of 29 patients [27.6%], was within 1mm of prosthetic valve size in 11 of 29 patients [37.9%], was within 2mm of prosthetic valve size in 8 of 29 patients, and was within 3mm of prosthetic valve size in 2 patients.

• The Journal of Advanced Prosthodontics
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• v.14 no.5
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• pp.334-334
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• 2022

• The Journal of Korea Robotics Society
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• v.14 no.3
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• pp.228-235
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• 2019

This paper presents a multiple DoFs (degrees-of-freedom) prosthetic forearm and sEMG (surface electromyogram) pattern recognition and motion intent classification of forearm amputee. The developed prosthetic forearm has 9 DoFs hand and single-DoF wrist, and the socket is designed considering wearability. In addition, the pattern recognition based on sEMG is proposed for prosthetic control. Several experiments were conducted to substantiate the performance of the prosthetic forearm. First, the developed prosthetic forearm could perform various motions required for activity of daily living of forearm amputee. It was able to control according to shape and size of the object. Additionally, the amputee was able to perform 'tying up shoe' using the prosthetic forearm. Secondly, pattern recognition and classification experiments using the sEMG signals were performed to find out whether it could classify the motions according to the user's intents. For this purpose, sEMG signals were applied to the multilayer perceptron (MLP) for training and testing. As a result, overall classification accuracy arrived at 99.6% for all participants, and all the postures showed more than 97% accuracy.

• Journal of Korean Foot and Ankle Society
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• v.12 no.1
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• pp.41-46
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• 2008

Purpose: This study was designed to evaluate characteristics of foot pressure distribution with or without partial prosthetic foot in transmetatarsal amputee. Materials and Methods: The subjects were 9 transmetatarsal amputees. Foot pressures were measured at hallux, the $1^{st}-5^{th}$ metatarsal head (MTH), mid-foot, condyle area by F-scan system in amputated or contralateral foot during active walking. Results: In amputated foot, mean peak pressure was greatest in midfoot without prosthetic foot but it was greatest in hindfoot with prosthetic foot. In unaffected foot, although mean peak pressure was higher in hallux, and $1-5^{th}$ MTH compared to amputated foot, it was greatest in hind foot both with and without prosthetic foot. However, in unaffected foot, mean peak pressure significantly decreased in hallux and $5^{th}$ MTH after wearing the prosthetic foot. There was a significant difference in mean peak pressure in hallux and $5^{th}$ MTH between amputated and unaffected foot after wearing prosthetic foot. However, other region had no significant difference with or without prosthetic foot between feet. Conclusions: The use of partial prosthetic foot tends to shift weight bearing from the heel area to forefoot and could significantly reduce hind foot peak pressure and redistributed to peak pressure. The partial prosthetic foot can also offer the peak pressure to reduction both amputated foot and unaffected foot and help to toe off during walking.

• Journal of Chest Surgery
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• v.17 no.1
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• pp.3-11
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• 1984

Prosthetic valve replacement has resulted in marked improvement in the functional status of many patients with valvular heart disease. But valve failure from various causes has necessitated re-replacement of prosthetic valve in some of these patients. This selective group of patients has many inherent problems. This report presents our experience with seven patients who received re-replacement of prosthetic valve in the Seoul National University Hospital from 1981, to 1983. The patients included one woman and six men in the range of 9 and 49 years old. As the first valve operations, there were five MVR using tissue valves, one DVR [Bjork-Shiley and Ionescu-Shiley valve] and one case of modified Bentall operation with composite graft [Ionescu-Shiley valve]. Reoperations on prosthetic valve failure were performed 17 to 54 months after the first operation [mean 34 months]. Amon8 seven patients, there were two cases of prosthetic valve endocarditis and five cases of primary tissue failure. Gross calcification of the xenograft was found in two children with Ionescu-Shiley valve. All except one had relatively successful operative results. The unsuccessful one died intraoperatively from low output syndrome.

• Journal of Chest Surgery
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• v.18 no.4
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• pp.655-662
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• 1985

From January 1985 to July 1985, prosthetic heart valves were replaced in 5 patients at Keimyung University Dongsan Medical Center. The patients included three women and two men ranging in age from 22 to 41 years. Three mitral valve replacements, one aortic valve replacement and one double valve replacement [mitral and aortic valve replacement] were done at the first valve operations. Reoperation were performed 2 to 76 months after the first operations, Prosthetic valve endocarditis occurred in 3 patients, early in one and late in two and primary valve failure occurred in 2 patients. In operative findings, vegetation in prosthetic valve endocarditis and calcification in primary valve failure were found. All except one had relatively successful operative results. One died of early fungal prosthetic valve endocarditis due to relapsed prosthetic valve endocarditis with heart failure and block.

• Journal of Korean society of Dental Hygiene
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• v.15 no.5
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• pp.777-786
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• 2015

Objectives: The purpose of the study was to investigate the influencing factors on anxiety and depression before and after prosthetic treatment in the patients. Methods: A self-reported questionnaire was completed by 248 patients with tooth loss and over 20 years old. The questionnaire was carried out before and after oral examination and dental prosthetic treatment from July to December, 2013. The study instruments included Beck's anxiety inventory and self-rating depression scale by Zung. The questionnaire was adapted and modified from Kwon's anxiety inventory and Lee's depression scale. Results: While the anxiety level increased from 69.4% to 78.2% in the normal people, the depression level changed from 53.2% to 64.1% in the normal people. The gender variable had a positive effect on anxiety and depression while educational level had a negative effect on them. The dental fear was closely related to anxiety and depression before and after the prosthetic treatment. The entire body health perception showed a negative effect on anxiety and depression. The distrust towards the dentist had an influence on the anxiety and depression in the prosthetic patients. Conclusions: The influencing factors on anxiety and depression in the prosthetic patients included gender, dental fear, entire body perception, and distrust towards the dentist.