Design optimization of a knee joint for an active transfemoral prosthesis for weight reduction

안형종,이광희,이철희 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.12

This paper describes the optimized design of a knee joint for an active transfemoral prosthesis with a fully active knee joint. The active transfemoral prosthesis which can help amputees to walk naturally with a powered motor has been actively developed around the world with advances in battery technology and others. However, most of them are designed for level walking, especially in South Korea, research about active prosthesis is insufficiently carried out, also depends on foreign technology. Therefore, this study focuses on the development of prosthetic knee joint that can overcome complex walking environment including stair walking. The developed prosthesis has one degree of freedom at the knee joint and can mimic the human walking mechanism. The prosthetic knee joint has a simple hightorque mechanism comprising a flat BLDC motor, harmonic drive, and pulley to generate the torque required for walking on stairs, which requires the largest torque. As one of the most important factors for comfort and fatigue, the total weight of the prosthesis should be minimized. Topology optimization was carried out to reduce the weight, and an advanced knee joint design was developed based on the optimization. The structural safety was validated via finite element analysis and a strain experiment under working conditions.

Temporomandibular joint reconstruction with alloplastic prosthesis: the outcomes of four cases

Park, Jung-Hyun,Jo, Eun,Cho, Hoon,Kim, Hyung Jun Korean Association of Maxillofacial Plastic and Re 2017 Maxillofacial Plastic Reconstructive Surgery Vol.39 No.-

Background: The purpose of this study is to evaluate the outcomes of four patients receiving stock Biomet TMJ prosthesis for reconstruction of the TMJs. Methods: TMJ reconstruction with stock Biomet TMJ prosthesis was performed in four patients who had joint damages by trauma, tumor, resorption, and ankylosis, which represent the indications of alloplastic prosthesis. Results: Loss of condyle from trauma and resorption of joint are good indications for prosthesis, but the patients should be informed about limitation of jaw movement. In case of structural damage of TMJ by tumor, tumor recurrence should be considered before planning TMJ reconstruction. Considering heterotopic bone formation in case of ankylosis, periodic follow-up and special surgical technique are required. Conclusions: Given careful treatment planning and understanding the functional limitation of TMJ prosthesis, alloplastic prosthesis is a safe and effective management option for the reconstruction of TMJs.

노면 적응형 대퇴 의족개발을 위한 발목 관절 부하가변형 하퇴 의족 적용에 대한 연구

엄수홍,나선종,류중현,박세훈,이응혁 한국전기전자학회 2019 전기전자학회논문지 Vol.23 No.3

This study is the method which is adapted to control ankle joint movement for resolving the problem of gait imbalancein intervals where gait environments are changed and slope walking, as applying terrain-adaptive technique to intelligentabove-knee prosthesis. In this development of above-knee prosthesis, to classify the gait modes is essential. Fordistinguishing the stance phases and the swing phase depending on roads, a machine learning which combines decisiontree and random forest from knee angle data and inertial sensor data, is proposed and adapted. By using this method, theankle movement state of the prosthesis is controlled. This study verifies whether the problem is resolved throughbutterfly diagram.

심한 퇴행성 악관절 질환 환자에서 보철성 과두를 이용한 하악과두 재건술의 치험례

전용민,김창현,차정섭,민경기,권종진,Jeon, Yong-Min,Kim, Chang-Hyun,Cha, Jeong-Seop,Min, Kyung-Gi,Kwon, Jong-Jin 대한악안면성형재건외과학회 2010 Maxillofacial Plastic Reconstructive Surgery Vol.32 No.2

This is a case report about patient who had suffered from degenerative joint disease and treated by TMJ reconstruction with condylar prosthesis. The patient visited Korea University An-am hospital on 2007 complaining symptom about both TMJ pain, mouth opening limitation and open bite. From CT view there was severe resorption of both condylar head, therefore condylar prosthesis reconstruction was planned. After 3D RP model analysis for preparation, the patient was operated under general anesthesia for condylar prosthesis reconstruction and the symptom was alleviated. (increased mouth opening, reduced anterior open bite, full mouth occlusal contact achieved) Follow up was carried out monthly, but after this, patient refused follow up. After 26 months from the operation, the patient revisited for anterior open bite. In clinical evaluation, occlusal contact was remained, but anterior open bite was relapsed. From cephalometry analysis, severe resorption of glenoid fossa was found. Therefore, Autogenous disc reconstruction with alloplastic material was planned on August 2009. After another surgery, condylar prosthesis was regained its normal position in glenoid fossa, and occlusion was recovered properly.

인공 발목관절의 기계적 성능평가

김충연,김환,김동욱,이성재,이권용 한국생체재료학회 2013 생체재료학회지 Vol.17 No.1

Total ankle replacement (TAR) is a surgical treatment for the osteoarthritis or bone fracture of ankle joint. Total ankle prosthesis is classified according to fixed and mobile types of components, kind of material of bearing component. International standard for testing the durability and safety of each component in TAR suggests to adopt the test method for total knee and/or hip prostheses. Mechanical test conditions for commercial product of Hintegra (Lyon, SA, France) were determined by conducting finite element analyses with a foot, prosthesis components, and surgical models. Constraint test between talus and polyethylene bearing components adopted ASTM F1223 for total knee replacement, and the design of talus and polyethylene bearing components provided information about constraint force until dislocation occurred. Cyclic fatigue test of tibia component adopted ASTM F1800 for total knee replacement, and there was no fatigue failure of tibia component during 5,000,000 cycles. In vitro wear simulation test of polyethylene bearing component adopted ISO 14242-1 for total hip-joint prostheses and a wear rate of 0.44 × 10−6 mg/cycles was observed during 1,000,000 cycles. In this study, mechanical test methods for evaluating total ankle joint prosthesis were developed on the base of international standard test methods of total hip and knee joint prostheses. However, this study was conducted on one commercial product. For the other products having different designs of total ankle prostheses, it is suggested to modify or adopt these test methods for their own products.

Alloplastic total temporomandibular joint replacement using stock prosthesis: a one-year follow-up report of two cases

Sang-Hoon Lee,Da-Jung Ryu,Hye-Sun Kim,Hyung-Gon Kim,Jong-Ki Huh 대한구강악안면외과학회 2013 대한구강악안면외과학회지 Vol.39 No.6

Alloplastic total replacement of the temporomandibular joint (TMJ) was developed in recent decades. In some conditions, previous studies suggested the rationale behind alloplastic TMJ replacement rather than reconstruction with autogenous grafts. Currently, three prosthetic products are available and approved by the US Food and Drug Administration. Among these products, customized prostheses are manufactured, via computer aided design/ computer aided manufacturing (CAD/CAM) system for customized design; stock-type prostheses are provided in various sizes and shapes. In this report, two patients (a 50-year-old female who had undergone condylectomy for the treatment of osteochondroma extending to the cranial base on the left condyle, and a 21-year-old male diagnosed with left temporomandibular ankylosis) were treated using the alloplastic total replacement of TMJ using stock prosthesis. The follow-up results of a favorable one-year, short-term therapeutic outcome were obtained for the alloplastic total TMJ replacement using a stock-type prosthesis.

Comparison of Patellofemoral Outcomes between Attune and PFC Sigma Designs: A Prospective Matched-Pair Analysis

Rajesh Navin Maniar,Nishit Bhatnagar,Rohan Bidwai,Ankur Dhiman,Debashish Chanda,Nishant Sanghavi 대한정형외과학회 2022 Clinics in Orthopedic Surgery Vol.14 No.1

Background: Attune (DePuy Synthes) prosthesis was designed to overcome patellofemoral complications associated with PFC Sigma (DePuy Synthes) prosthesis. The aim of our study was to compare the incidence of anterior knee pain (AKP), patellofemoral crepitus (PCr), and functional outcome between them. Methods: This prospective matched-pair study was conducted between January 2014 and June 2015, during which 75 consecutive Attune total knee arthroplasties (TKAs) were matched with 75 PFC Sigma TKAs based on age, sex, body mass index, pathology, and deformity. A single surgeon performed all the operations with aid of computer navigation, using a posterior-stabilized prosthesis with patellar resurfacing. Outcome was assessed by new Knee Society Score (NKSS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. AKP and PCr were assessed by a patient-administered questionnaire till 2 years of follow-up. Three pairs were lost to follow-up and finally 72 pairs were analyzed. Results: One patient in each group reported AKP and 1 patient from each group had PCr at 2 years postoperatively. None of these patients required additional surgery. The incidence of lateral retinacular release was higher with PFC Sigma (5/72) than Attune (2/72); however, this was statistically not significant (p = 0.4). The Attune group had a significantly greater range of motion (ROM) at 3 months postoperatively (p = 0.049). At final follow-up, ROM was comparable between two prosthesis designs. NKSS and WOMAC scores were also comparable between the groups. Conclusions: We observed that both Attune and PFC Sigma had a low and comparable incidence of AKP and PCr up to 2 years of follow-up. The Attune group achieved a significantly greater ROM at 3 months postoperatively. At 2 years of follow-up, both prostheses had excellent and comparable clinical and functional results.

Reduction of the Femoral Head First, and Assembly of the MUTARS® Device in Case of Impossible Reduction during Total Hip Arthroplasty

Jee Young Lee,이예준,공규민 대한고관절학회 2023 Hip and Pelvis Vol.35 No.4

Dislocation after a total hip arthroplasty occurs in approximately 1% of patients; however, the frequency is much higher after revision surgery. To prevent dislocation, use of a larger femoral head is recommended, and a dual mobility femoral head has been introduced. However, reducing the dual mobility femoral head to the acetabular component is difficult in cases involving contracture in the soft tissue around the joint. A 72-year-old male patient who developed a periprosthetic joint infection underwent two-stage revision surgery using MUTARS®. Two months after the revision, the hip joint became dislocated and manual reduction was attempted; however, dislocation occurred again. During another revision using a dual mobility bearing, the soft tissue around the hip joint was too tight to reduce. The problem was overcome by first repositioning the dual mobility head into the acetabular socket, followed by assembly of the diaphyseal portion of the implant.

The use of computer-aided design and computer-aided manufacturing fabricated titanium prosthesis to restore maxillofacial defects: 4 cases report

Ali Alqussair,Seunghyun Rhee,Jin-Young Choi 대한미용의학회 2019 대한미용의학회지 Vol.3 No.1

Computer-aided design and computer-aided manufacturing (CAD-CAM) techniques are leading to new and refined approaches to reconstructive surgery. While used mainly in craniofacial reconstruction so far, CAD-CAM technology has the potential for advances in every area of plastic and reconstructive surgery. Here we are reporting 4 different cases of maxillofacial defects reconstruction and the purpose of this report is to introduce a new methodology for contour restoration of the maxillofacial defects using CAD-CAM custom-made titanium prosthesis. With the help of CAD-CAM technology the rigid fixation of the custom-made titanium implants successfully restores the contour of maxillofacial defects in more symmetrical and aesthetic shape. However, without this technology restoring large defect is difficult as it requires strong prosthetic material like titanium use to restore the mandibular angle and border defects. We think that titanium prosthesis is an excellent choice for efficient and durable reconstruction of such large maxillofacial defects.

굴곡이 가능한 다축관절기능의 검지 손가락 설계

정진석(jin-seok Jung),허현(Hyun Heo),진도훈(Do-Hun Chin),조희근(Hee-kuen Cho),김종도(jong-do Kim),윤문철(Moon-Chul Yoon) 한국기계가공학회 2007 한국기계가공학회 춘추계학술대회 논문집 Vol.2007 No.-

It is necessary to develope the functional finger prosthesis with multi-axis joints which is used for pinching and griping. Also, to analyze the function of the thumb and index finger having an important role in the function of the finger prosthesis is essential too. Nowadays the finger prostheses including the electronic prosthesis is used to pinch a simple product. However it does not satisfy the requirement of various functions of the disabled. There are several robot hands with many degree of freedom, although it is not light weighted and minimum volume. A study of the finger prosthesis is required to overcome the problem of weight and volume. The finger prosthesis developed in this study can flex up to about 90° in the metacarpal phalangeal joint and the proximal inter phalangeal joint and the distal inter phalangeal joint which can't be achieved the grip motion before was developed. The weight of the prosthesis is optimized to minimize and this developed prosthesis can be used conveniently.