Surface EMG in advanced hand prosthetics.

Science.gov (United States)

Castellini, Claudio; van der Smagt, Patrick

2009-01-01

One of the major problems when dealing with highly dexterous, active hand prostheses is their control by the patient wearing them. With the advances in mechatronics, building prosthetic hands with multiple active degrees of freedom is realisable, but actively controlling the position and especially the exerted force of each finger cannot yet be done naturally. This paper deals with advanced robotic hand control via surface electromyography. Building upon recent results, we show that machine learning, together with a simple downsampling algorithm, can be effectively used to control on-line, in real time, finger position as well as finger force of a highly dexterous robotic hand. The system determines the type of grasp a human subject is willing to use, and the required amount of force involved, with a high degree of accuracy. This represents a remarkable improvement with respect to the state-of-the-art of feed-forward control of dexterous mechanical hands, and opens up a scenario in which amputees will be able to control hand prostheses in a much finer way than it has so far been possible.

An Approach for Pattern Recognition of EEG Applied in Prosthetic Hand Drive

Directory of Open Access Journals (Sweden)

Xiao-Dong Zhang

2011-12-01

Full Text Available For controlling the prosthetic hand by only electroencephalogram (EEG, it has become the hot spot in robotics research to set up a direct communication and control channel between human brain and prosthetic hand. In this paper, the EEG signal is analyzed based on multi-complicated hand activities. And then, two methods of EEG pattern recognition are investigated, a neural prosthesis hand system driven by BCI is set up, which can complete four kinds of actions (arm’s free state, arm movement, hand crawl, hand open. Through several times of off-line and on-line experiments, the result shows that the neural prosthesis hand system driven by BCI is reasonable and feasible, the C-support vector classifiers-based method is better than BP neural network on the EEG pattern recognition for multi-complicated hand activities.

Neural-Network Control Of Prosthetic And Robotic Hands

Science.gov (United States)

Buckley, Theresa M.

1991-01-01

Electronic neural networks proposed for use in controlling robotic and prosthetic hands and exoskeletal or glovelike electromechanical devices aiding intact but nonfunctional hands. Specific to patient, who activates grasping motion by voice command, by mechanical switch, or by myoelectric impulse. Patient retains higher-level control, while lower-level control provided by neural network analogous to that of miniature brain. During training, patient teaches miniature brain to perform specialized, anthropomorphic movements unique to himself or herself.

Tactile Sensing Reflexes for Advanced Prosthetic Hands

Science.gov (United States)

2016-10-01

Jeremy A. Fishel, Member, IEEE Figure 1. A) Custom NumaTac prosthetic fingertip sensor core and foam; B) Ottobock VariPlus Speed hand installed with two...oal – H ardw are P rototype D evelopm ent R   Identify alternatives for outcom e m easures R   E xplore sensor design param eters C Y16 G oals – C

A mechatronics platform to study prosthetic hand control using EMG signals.

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Geethanjali, P

2016-09-01

In this paper, a low-cost mechatronics platform for the design and development of robotic hands as well as a surface electromyogram (EMG) pattern recognition system is proposed. This paper also explores various EMG classification techniques using a low-cost electronics system in prosthetic hand applications. The proposed platform involves the development of a four channel EMG signal acquisition system; pattern recognition of acquired EMG signals; and development of a digital controller for a robotic hand. Four-channel surface EMG signals, acquired from ten healthy subjects for six different movements of the hand, were used to analyse pattern recognition in prosthetic hand control. Various time domain features were extracted and grouped into five ensembles to compare the influence of features in feature-selective classifiers (SLR) with widely considered non-feature-selective classifiers, such as neural networks (NN), linear discriminant analysis (LDA) and support vector machines (SVM) applied with different kernels. The results divulged that the average classification accuracy of the SVM, with a linear kernel function, outperforms other classifiers with feature ensembles, Hudgin's feature set and auto regression (AR) coefficients. However, the slight improvement in classification accuracy of SVM incurs more processing time and memory space in the low-level controller. The Kruskal-Wallis (KW) test also shows that there is no significant difference in the classification performance of SLR with Hudgin's feature set to that of SVM with Hudgin's features along with AR coefficients. In addition, the KW test shows that SLR was found to be better in respect to computation time and memory space, which is vital in a low-level controller. Similar to SVM, with a linear kernel function, other non-feature selective LDA and NN classifiers also show a slight improvement in performance using twice the features but with the drawback of increased memory space requirement and time

A Prosthetic Hand Body Area Controller Based on Efficient Pattern Recognition Control Strategies.

Science.gov (United States)

Benatti, Simone; Milosevic, Bojan; Farella, Elisabetta; Gruppioni, Emanuele; Benini, Luca

2017-04-15

Poliarticulated prosthetic hands represent a powerful tool to restore functionality and improve quality of life for upper limb amputees. Such devices offer, on the same wearable node, sensing and actuation capabilities, which are not equally supported by natural interaction and control strategies. The control in state-of-the-art solutions is still performed mainly through complex encoding of gestures in bursts of contractions of the residual forearm muscles, resulting in a non-intuitive Human-Machine Interface (HMI). Recent research efforts explore the use of myoelectric gesture recognition for innovative interaction solutions, however there persists a considerable gap between research evaluation and implementation into successful complete systems. In this paper, we present the design of a wearable prosthetic hand controller, based on intuitive gesture recognition and a custom control strategy. The wearable node directly actuates a poliarticulated hand and wirelessly interacts with a personal gateway (i.e., a smartphone) for the training and personalization of the recognition algorithm. Through the whole system development, we address the challenge of integrating an efficient embedded gesture classifier with a control strategy tailored for an intuitive interaction between the user and the prosthesis. We demonstrate that this combined approach outperforms systems based on mere pattern recognition, since they target the accuracy of a classification algorithm rather than the control of a gesture. The system was fully implemented, tested on healthy and amputee subjects and compared against benchmark repositories. The proposed approach achieves an error rate of 1.6% in the end-to-end real time control of commonly used hand gestures, while complying with the power and performance budget of a low-cost microcontroller.

Rapid prototyping prosthetic hand acting by a low-cost shape-memory-alloy actuator.

Science.gov (United States)

Soriano-Heras, Enrique; Blaya-Haro, Fernando; Molino, Carlos; de Agustín Del Burgo, José María

2018-06-01

The purpose of this article is to develop a new concept of modular and operative prosthetic hand based on rapid prototyping and a novel shape-memory-alloy (SMA) actuator, thus minimizing the manufacturing costs. An underactuated mechanism was needed for the design of the prosthesis to use only one input source. Taking into account the state of the art, an underactuated mechanism prosthetic hand was chosen so as to implement the modifications required for including the external SMA actuator. A modular design of a new prosthesis was developed which incorporated a novel SMA actuator for the index finger movement. The primary objective of the prosthesis is achieved, obtaining a modular and functional low-cost prosthesis based on additive manufacturing executed by a novel SMA actuator. The external SMA actuator provides a modular system which allows implementing it in different systems. This paper combines rapid prototyping and a novel SMA actuator to develop a new concept of modular and operative low-cost prosthetic hand.

Cyborg beast: a low-cost 3d-printed prosthetic hand for children with upper-limb differences.

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Zuniga, Jorge; Katsavelis, Dimitrios; Peck, Jean; Stollberg, John; Petrykowski, Marc; Carson, Adam; Fernandez, Cristina

2015-01-20

There is an increasing number of children with traumatic and congenital hand amputations or reductions. Children's prosthetic needs are complex due to their small size, constant growth, and psychosocial development. Families' financial resources play a crucial role in the prescription of prostheses for their children, especially when private insurance and public funding are insufficient. Electric-powered (i.e., myoelectric) and body-powered (i.e., mechanical) devices have been developed to accommodate children's needs, but the cost of maintenance and replacement represents an obstacle for many families. Due to the complexity and high cost of these prosthetic hands, they are not accessible to children from low-income, uninsured families or to children from developing countries. Advancements in computer-aided design (CAD) programs, additive manufacturing, and image editing software offer the possibility of designing, printing, and fitting prosthetic hands devices at a distance and at very low cost. The purpose of this preliminary investigation was to describe a low-cost three-dimensional (3D)-printed prosthetic hand for children with upper-limb reductions and to propose a prosthesis fitting methodology that can be performed at a distance. No significant mean differences were found between the anthropometric and range of motion measurements taken directly from the upper limbs of subjects versus those extracted from photographs. The Bland and Altman plots show no major bias and narrow limits of agreements for lengths and widths and small bias and wider limits of agreements for the range of motion measurements. The main finding of the survey was that our prosthetic device may have a significant potential to positively impact quality of life and daily usage, and can be incorporated in several activities at home and in school. This investigation describes a low-cost 3D-printed prosthetic hand for children and proposes a distance fitting procedure. The Cyborg Beast

Experimental Study of Real-Time Classification of 17 Voluntary Movements for Multi-Degree Myoelectric Prosthetic Hand

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Trongmun Jiralerspong

2017-11-01

Full Text Available The myoelectric prosthetic hand is a powerful tool developed to help people with upper limb loss restore the functions of a biological hand. Recognizing multiple hand motions from only a few electromyography (EMG sensors is one of the requirements for the development of prosthetic hands with high level of usability. This task is highly challenging because both classification rate and misclassification rate worsen with additional hand motions. This paper presents a signal processing technique that uses spectral features and an artificial neural network to classify 17 voluntary movements from EMG signals. The main highlight will be on the use of a small set of low-cost EMG sensor for classification of a reasonably large number of hand movements. The aim of this work is to extend the capabilities to recognize and produce multiple movements beyond what is currently feasible. This work will also show and discuss about how tailoring the number of hand motions for a specific task can help develop a more reliable prosthetic hand system. Online classification experiments have been conducted on seven male and five female participants to evaluate the validity of the proposed method. The proposed algorithm achieves an overall correct classification rate of up to 83%, thus, demonstrating the potential to classify 17 movements from 6 EMG sensors. Furthermore, classifying 9 motions using this method could achieve an accuracy of up to 92%. These results show that if the prosthetic hand is intended for a specific task, limiting the number of motions can significantly increase the performance and usability.

Implantable electronics of a closed-loop system for controlling prosthetic hands

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Nikas Antonios

2017-09-01

Full Text Available This paper presents the design of implantable electronics as a part of a system for prosthetic hand control. Purpose of the implant is the sensing of electrical signals originating from biological tissue and the actuation of the same, therefore closing the loop and allowing for an improved control of the prosthetic hand. The implant contains two integrated circuits for eight channel EMG monitoring and four channel stimulation, respectively. An on-board microcontroller allows for local pre-processing. All intracorporeal to extracorporeal communications are running through and are directed by the main processing platform. The external components of the control system include, in addition to the main processing and control platform, the inductive power transfer circuits and the pressure sensors for the sensory feedback. Different assembly and encapsulation options are taken into account for the implantable electronics and are unified in a single PCB design.

Towards the design of a prosthetic underactuated hand

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T. Laliberté

2010-12-01

Full Text Available This paper presents recent advances in the design of an underactuated hand for applications in prosthetics. First, the design of the fingers is addressed. Based on previous experiments with prototypes developed in the past, new tendon routings are proposed that lead to a more effective transmission of the forces. A novel elastic tendon routing is also proposed for the passive opening of the hand. A simplified static analysis of the fingers is proposed to support the results. Then, a new kinematic design of the thumb is presented. The thumb is designed to perform out-of-the-plane motions in order to broaden the variety of possible grasps. A mechanism for the implementation of underactuation between the fingers is proposed that alleviates the friction problems encountered in earlier hand designs. Finally, a prototype of the hand is briefly described and typical grasps are shown.

This paper was presented at the IFToMM/ASME International Workshop on Underactuated Grasping (UG2010, 19 August 2010, Montréal, Canada.

A Quality Function Deployment (QFD) approach to designing a prosthetic myoelectric hand

OpenAIRE

Erika Sofía Olaya Escobar; Carlos Julio Cortés Rodríguez; Óscar Germán Duarte Velasco

2005-01-01

This paper presents a Quality Function Deployment (QFD) model based on computing with words. It is specifically used in the House of Quality (HOQ) construction phase. It illustrates the methodology employed in designing a prosthetic myoelectric hand.

Psycho-physiological assessment of a prosthetic hand sensory feedback system based on an auditory display: a preliminary study.

Science.gov (United States)

Gonzalez, Jose; Soma, Hirokazu; Sekine, Masashi; Yu, Wenwei

2012-06-09

Prosthetic hand users have to rely extensively on visual feedback, which seems to lead to a high conscious burden for the users, in order to manipulate their prosthetic devices. Indirect methods (electro-cutaneous, vibrotactile, auditory cues) have been used to convey information from the artificial limb to the amputee, but the usability and advantages of these feedback methods were explored mainly by looking at the performance results, not taking into account measurements of the user's mental effort, attention, and emotions. The main objective of this study was to explore the feasibility of using psycho-physiological measurements to assess cognitive effort when manipulating a robot hand with and without the usage of a sensory substitution system based on auditory feedback, and how these psycho-physiological recordings relate to temporal and grasping performance in a static setting. 10 male subjects (26+/-years old), participated in this study and were asked to come for 2 consecutive days. On the first day the experiment objective, tasks, and experiment setting was explained. Then, they completed a 30 minutes guided training. On the second day each subject was tested in 3 different modalities: Auditory Feedback only control (AF), Visual Feedback only control (VF), and Audiovisual Feedback control (AVF). For each modality they were asked to perform 10 trials. At the end of each test, the subject had to answer the NASA TLX questionnaire. Also, during the test the subject's EEG, ECG, electro-dermal activity (EDA), and respiration rate were measured. The results show that a higher mental effort is needed when the subjects rely only on their vision, and that this effort seems to be reduced when auditory feedback is added to the human-machine interaction (multimodal feedback). Furthermore, better temporal performance and better grasping performance was obtained in the audiovisual modality. The performance improvements when using auditory cues, along with vision

Illusory movement perception improves motor control for prosthetic hands

Science.gov (United States)

Marasco, Paul D.; Hebert, Jacqueline S.; Sensinger, Jon W.; Shell, Courtney E.; Schofield, Jonathon S.; Thumser, Zachary C.; Nataraj, Raviraj; Beckler, Dylan T.; Dawson, Michael R.; Blustein, Dan H.; Gill, Satinder; Mensh, Brett D.; Granja-Vazquez, Rafael; Newcomb, Madeline D.; Carey, Jason P.; Orzell, Beth M.

2018-01-01

To effortlessly complete an intentional movement, the brain needs feedback from the body regarding the movement’s progress. This largely non-conscious kinesthetic sense helps the brain to learn relationships between motor commands and outcomes to correct movement errors. Prosthetic systems for restoring function have predominantly focused on controlling motorized joint movement. Without the kinesthetic sense, however, these devices do not become intuitively controllable. Here we report a method for endowing human amputees with a kinesthetic perception of dexterous robotic hands. Vibrating the muscles used for prosthetic control via a neural-machine interface produced the illusory perception of complex grip movements. Within minutes, three amputees integrated this kinesthetic feedback and improved movement control. Combining intent, kinesthesia, and vision instilled participants with a sense of agency over the robotic movements. This feedback approach for closed-loop control opens a pathway to seamless integration of minds and machines. PMID:29540617

A Quality Function Deployment (QFD approach to designing a prosthetic myoelectric hand

Directory of Open Access Journals (Sweden)

Erika Sofía Olaya Escobar

2005-05-01

Full Text Available This paper presents a Quality Function Deployment (QFD model based on computing with words. It is specifically used in the House of Quality (HOQ construction phase. It illustrates the methodology employed in designing a prosthetic myoelectric hand.

Design for a three-fingered hand. [robotic and prosthetic applications

Science.gov (United States)

Crossley, F. R. E.

1977-01-01

This paper describes the construction of a prototype mechanical hand or 'end effector' for use on a remotely controlled robot, but with possible application as a prosthetic device. An analysis of hand motions is reported, from which it is concluded that the two most important manipulations (apart from grasps) are to be able to pick up a tool and draw it into a nested grip against the palm, and to be able to hold a pistol-grip tool such as an electric drill and pull the trigger. One of our models was tested and found capable of both these operations.

Effect of clinical parameters on the control of myoelectric robotic prosthetic hands.

Science.gov (United States)

Atzori, Manfredo; Gijsberts, Arjan; Castellini, Claudio; Caputo, Barbara; Hager, Anne-Gabrielle Mittaz; Elsig, Simone; Giatsidis, Giorgio; Bassetto, Franco; Müller, Henning

2016-01-01

Improving the functionality of prosthetic hands with noninvasive techniques is still a challenge. Surface electromyography (sEMG) currently gives limited control capabilities; however, the application of machine learning to the analysis of sEMG signals is promising and has recently been applied in practice, but many questions still remain. In this study, we recorded the sEMG activity of the forearm of 11 male subjects with transradial amputation who were mentally performing 40 hand and wrist movements. The classification performance and the number of independent movements (defined as the subset of movements that could be distinguished with >90% accuracy) were studied in relationship to clinical parameters related to the amputation. The analysis showed that classification accuracy and the number of independent movements increased significantly with phantom limb sensation intensity, remaining forearm percentage, and temporal distance to the amputation. The classification results suggest the possibility of naturally controlling up to 11 movements of a robotic prosthetic hand with almost no training. Knowledge of the relationship between classification accuracy and clinical parameters adds new information regarding the nature of phantom limb pain as well as other clinical parameters, and it can lay the foundations for future "functional amputation" procedures in surgery.

Mechanical design of a shape memory alloy actuated prosthetic hand.

Science.gov (United States)

De Laurentis, Kathryn J; Mavroidis, Constantinos

2002-01-01

This paper presents the mechanical design for a new five fingered, twenty degree-of-freedom dexterous hand patterned after human anatomy and actuated by Shape Memory Alloy artificial muscles. Two experimental prototypes of a finger, one fabricated by traditional means and another fabricated by rapid prototyping techniques, are described and used to evaluate the design. An important aspect of the Rapid Prototype technique used here is that this multi-articulated hand will be fabricated in one step, without requiring assembly, while maintaining its desired mobility. The use of Shape Memory Alloy actuators combined with the rapid fabrication of the non-assembly type hand, reduce considerably its weight and fabrication time. Therefore, the focus of this paper is the mechanical design of a dexterous hand that combines Rapid Prototype techniques and smart actuators. The type of robotic hand described in this paper can be utilized for applications requiring low weight, compactness, and dexterity such as prosthetic devices, space and planetary exploration.

Illusory movement perception improves motor control for prosthetic hands.

Science.gov (United States)

Marasco, Paul D; Hebert, Jacqueline S; Sensinger, Jon W; Shell, Courtney E; Schofield, Jonathon S; Thumser, Zachary C; Nataraj, Raviraj; Beckler, Dylan T; Dawson, Michael R; Blustein, Dan H; Gill, Satinder; Mensh, Brett D; Granja-Vazquez, Rafael; Newcomb, Madeline D; Carey, Jason P; Orzell, Beth M

2018-03-14

To effortlessly complete an intentional movement, the brain needs feedback from the body regarding the movement's progress. This largely nonconscious kinesthetic sense helps the brain to learn relationships between motor commands and outcomes to correct movement errors. Prosthetic systems for restoring function have predominantly focused on controlling motorized joint movement. Without the kinesthetic sense, however, these devices do not become intuitively controllable. We report a method for endowing human amputees with a kinesthetic perception of dexterous robotic hands. Vibrating the muscles used for prosthetic control via a neural-machine interface produced the illusory perception of complex grip movements. Within minutes, three amputees integrated this kinesthetic feedback and improved movement control. Combining intent, kinesthesia, and vision instilled participants with a sense of agency over the robotic movements. This feedback approach for closed-loop control opens a pathway to seamless integration of minds and machines. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Functional and Psychosocial Outcomes of Hand Transplantation Compared with Prosthetic Fitting in Below-Elbow Amputees: A Multicenter Cohort Study.

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Stefan Salminger

Full Text Available Hand-transplantation and improvements in the field of prostheses opened new frontiers in restoring hand function in below-elbow amputees. Both concepts aim at restoring reliable hand function, however, the indications, advantages and limitations for each treatment must be carefully considered depending on level and extent of amputation. Here we report our findings of a multi-center cohort study comparing hand function and quality-of-life of people with transplanted versus prosthetic hands.Hand function in amputees with either transplant or prostheses was tested with Action Research Arm Test (ARAT, Southampton Hand Assessment Procedure (SHAP and the Disabilities of the Arm, Shoulder and Hand measure (DASH. Quality-of-life was compared with the Short-Form 36 (SF-36.Transplanted patients (n = 5 achieved a mean ARAT score of 40.86 ± 8.07 and an average SHAP score of 75.00 ± 11.06. Prosthetic patients (n = 7 achieved a mean ARAT score of 39.00 ± 3.61 and an average SHAP score of 75.43 ± 10.81. There was no significant difference between transplanted and prosthetic hands in ARAT, SHAP or DASH. While quality-of-life metrics were equivocal for four scales of the SF-36, transplanted patients reported significantly higher scores in "role-physical" (p = 0.006, "vitality" (p = 0.008, "role-emotional" (p = 0.035 and "mental-health" (p = 0.003.The indications for hand transplantation or prosthetic fitting in below-elbow amputees require careful consideration. As functional outcomes were not significantly different between groups, patient's best interests and the route of least harm should guide treatment. Due to the immunosuppressive side-effects, the indication for allotransplantation must still be restrictive, the best being bilateral amputees.

The influence of environmental and personal factors on participation of lower-limb prosthetic users in low-income countries: prosthetists' perspectives.

Science.gov (United States)

Kam, Season; Kent, Mallory; Khodaverdian, Alin; Daiter, Liane; Njelesani, Janet; Cameron, Debra; Andrysek, Jan

2015-05-01

To examine the environmental and personal factors in low-income countries (LICs) that influence prosthetic rehabilitation of adults with lower-limb (LL) amputations and their ability to participate in daily activities. In this qualitative descriptive study, 11 prosthetists participated in semi-structured interviews by telephone or Skype. Qualitative thematic analysis was guided by the International Classification of Function. Facilitating continuity of care, consideration of physical environments and usage, prosthetic quality including durability and socket fit, and minimizing the visibility of disability, were found to be important factors affecting the provision of prosthetic services in LICs. Environmental and personal factors must be considered when providing prosthetic rehabilitation for adults with LL amputations in LICs in order to optimize participation in activities. Results from this study provide new insights about some of the factors that influence the ability of individuals with LL amputations to rehabilitate to a level where they are able to participate in meaningful activities within their communities. There are unique environmental and personal components that can influence activity and participation of lower-limb (LL) prosthetic users in low-income countries (LICs). These components are often overlooked in the design of prosthetic devices and provision of prosthetic services. Continuity of care, condition of the post-surgical residuum, outdoor environments of common occupations, aesthetics and durability of prostheses, and user comfort should all be considered when providing prosthetic rehabilitation to adults with LL amputations in LICs to promote activity and participation. Results of our study can inform the practice of prosthetists in LICs by highlighting their contributions in enabling participation for LL prosthetic users. Our results can also inform the design of durable and comfortable prostheses and the provision of more appropriate

Psycho-physiological assessment of a prosthetic hand sensory feedback system based on an auditory display: a preliminary study

Directory of Open Access Journals (Sweden)

Gonzalez Jose

2012-06-01

Full Text Available Abstract Background Prosthetic hand users have to rely extensively on visual feedback, which seems to lead to a high conscious burden for the users, in order to manipulate their prosthetic devices. Indirect methods (electro-cutaneous, vibrotactile, auditory cues have been used to convey information from the artificial limb to the amputee, but the usability and advantages of these feedback methods were explored mainly by looking at the performance results, not taking into account measurements of the user’s mental effort, attention, and emotions. The main objective of this study was to explore the feasibility of using psycho-physiological measurements to assess cognitive effort when manipulating a robot hand with and without the usage of a sensory substitution system based on auditory feedback, and how these psycho-physiological recordings relate to temporal and grasping performance in a static setting. Methods 10 male subjects (26+/-years old, participated in this study and were asked to come for 2 consecutive days. On the first day the experiment objective, tasks, and experiment setting was explained. Then, they completed a 30 minutes guided training. On the second day each subject was tested in 3 different modalities: Auditory Feedback only control (AF, Visual Feedback only control (VF, and Audiovisual Feedback control (AVF. For each modality they were asked to perform 10 trials. At the end of each test, the subject had to answer the NASA TLX questionnaire. Also, during the test the subject’s EEG, ECG, electro-dermal activity (EDA, and respiration rate were measured. Results The results show that a higher mental effort is needed when the subjects rely only on their vision, and that this effort seems to be reduced when auditory feedback is added to the human-machine interaction (multimodal feedback. Furthermore, better temporal performance and better grasping performance was obtained in the audiovisual modality. Conclusions The performance

Control of a powered prosthetic device via a pinch gesture interface

Science.gov (United States)

Yetkin, Oguz; Wallace, Kristi; Sanford, Joseph D.; Popa, Dan O.

2015-06-01

A novel system is presented to control a powered prosthetic device using a gesture tracking system worn on a user's sound hand in order to detect different grasp patterns. Experiments are presented with two different gesture tracking systems: one comprised of Conductive Thimbles worn on each finger (Conductive Thimble system), and another comprised of a glove which leaves the fingers free (Conductive Glove system). Timing tests were performed on the selection and execution of two grasp patterns using the Conductive Thimble system and the iPhone app provided by the manufacturer. A modified Box and Blocks test was performed using Conductive Glove system and the iPhone app provided by Touch Bionics. The best prosthetic device performance is reported with the developed Conductive Glove system in this test. Results show that these low encumbrance gesture-based wearable systems for selecting grasp patterns may provide a viable alternative to EMG and other prosthetic control modalities, especially for new prosthetic users who are not trained in using EMG signals.

Initial Clinical Evaluation of the Modular Prosthetic Limb

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Briana N. Perry

2018-03-01

Full Text Available The Modular Prosthetic Limb (MPL was examined for its feasibility and usability as an advanced, dexterous upper extremity prosthesis with surface electromyography (sEMG control in with two individuals with below-elbow amputations. Compared to currently marketed prostheses, the MPL has a greater number of sequential and simultaneous degrees of motion, as well as wrist modularity, haptic feedback, and individual digit control. The MPL was successfully fit to a 33-year-old with a trans-radial amputation (TR01 and a 30-year-old with a wrist disarticulation amputation (TR02. To preserve anatomical limb length, we adjusted the powered degrees of freedom of wrist motion between users. Motor training began with practicing sEMG and pattern recognition control within the virtual integration environment (VIE. Prosthetic training sessions then allowed participants to complete a variety of activities of daily living with the MPL. Training and Motion Control Accuracy scores quantified their ability to consistently train and execute unique muscle-to-motion contraction patterns. Each user also completed one prosthetic functional metric—the Southampton Hand Assessment Procedure (SHAP for TR01 and the Jebsen-Taylor Hand Function Test (JHFT for TR02. Haptic feedback capabilities were integrated for TR01. TR01 achieved 95% accuracy at 84% of his VIE sessions. He demonstrated improved scores over a year of prosthetic training sessions, ultimately achieving simultaneous control of 13 of the 17 (76% attempted motions. His performance on the SHAP improved from baseline to final assessment with an increase in number of tasks achieved. TR01 also used vibrotactile sensors to successfully discriminate between hard and soft objects being grasped by the MPL hand. TR02 demonstrated 95% accuracy at 79% of his VIE sessions. He demonstrated improved scores over months of prosthetic training sessions, however there was a significant drop in scores initially following a mid

The Ninapro database: A resource for sEMG naturally controlled robotic hand prosthetics.

Science.gov (United States)

Atzori, Manfredo; Muller, Henning

2015-01-01

The dexterous natural control of robotic prosthetic hands with non-invasive techniques is still a challenge: surface electromyography gives some control capabilities but these are limited, often not natural and require long training times; the application of pattern recognition techniques recently started to be applied in practice. While results in the scientific literature are promising they have to be improved to reach the real needs. The Ninapro database aims to improve the field of naturally controlled robotic hand prosthetics by permitting to worldwide research groups to develop and test movement recognition and force control algorithms on a benchmark database. Currently, the Ninapro database includes data from 67 intact subjects and 11 amputated subject performing approximately 50 different movements. The data are aimed at permitting the study of the relationships between surface electromyography, kinematics and dynamics. The Ninapro acquisition protocol was created in order to be easy to be reproduced. Currently, the number of datasets included in the database is increasing thanks to the collaboration of several research groups.

Fabrication, sensation and control of fluidic elastomer actuators and their application towards hand orthotics and prosthetics

Science.gov (United States)

Zhao, Huichan

Due to their continuous and natural motion, fluidic elastomer actuators (FEAs) have shown potential in a range of robotic applications including prosthetics and orthotics. Despite their advantages and rapid developments, robots using these actuators still have several challenging issues to be addressed. First, the reliable production of low cost and complex actuators that can apply high forces is necessary, yet none of existing fabrication methods are both easy to implement and of high force output. Next, compliant or stretchable sensors that can be embedded into their bodies for sophisticated functions are required, however, many of these sensors suffer from hysteresis, fabrication complexity, chemical safety and environmental instability, and material incompatibility with soft actuators. Finally, feedback control for FEAs is necessary to achieve better performance, but most soft robots are still "open-loop". In this dissertation, I intend to help solve the above issues and drive the applications of soft robotics towards hand orthotics and prosthetics. First, I adapt rotational casting as a new manufacturing method for soft actuators. I present a cuboid soft actuator that can generate a force of >25 N at its tip, a near ten-fold increase over similar actuators previously reported. Next, I propose a soft orthotic finger with position control enabled via embedded optical fiber. I monitor both the static and dynamic states via the optical sensor and achieve the prescribed curvatures accurately and with stability by a gain-scheduled proportional-integral-derivative controller. Then I develop the soft orthotic fingers into a low-cost, closed-loop controlled, soft orthotic glove that can be worn by a typical human hand and helpful for grasping light objects, while also providing finger position control. I achieve motion control with inexpensive, binary pneumatic switches controlled by a simple finite-state-machine. Finally, I report the first use of stretchable optical

Amputation and Prosthetics

Science.gov (United States)

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VARIABLE STIFFNESS HAND PROSTHESIS: A SYSTEMATIC REVIEW

Directory of Open Access Journals (Sweden)

S. Cecilia Tapia-Siles

2017-06-01

Full Text Available Prosthetics is an important field in engineering due to the large number of amputees worldwide and the associated problems such as limited functionality of the state of the art. An important functionality of the human hand is its capability of adjusting the stiffness of the joints depending on the currently performed task. For the development of new technology it is important to understand the limitations of existing resources. As part of our efforts to develop a variable stiffness grasper for developing countries a systematic review was performed covering technology of body powered and myoelectric hand prosthesis. Focus of the review is readiness of prosthetic hands regarding their capability of controlling the stiffness of the end effector. Publications sourced through three different digital libraries were systematically reviewed on the basis of the PRISMA standard. We present a search strategy as well as the PRISMA assessment of the resulting records which covered 321 publications. The records were assessed and the results are presented for the ability of devices to control their joint stiffness. The review indicates that body powered prosthesis are preferred to myoelectric hands due to the reduced cost, the simplicity of use and because of their inherent ability to provide feedback to the user. Stiffness control was identified but has not been fully covered in the current state of the art. In addition we summarise the identified requirements on prosthetic hands as well as related information which can support the development of new prosthetics.

New developments in prosthetic arm systems

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Vujaklija I

2016-07-01

Full Text Available Ivan Vujaklija,1 Dario Farina,1 Oskar C Aszmann2 1Institute of Neurorehabilitation Systems, Bernstein Focus Neurotechnology Göttingen, University Medical Center Göttingen, Georg-August University, Göttingen, Germany; 2Christian Doppler Laboratory for Restoration of Extremity Function, Division of Plastic and Reconstructive Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria Abstract: Absence of an upper limb leads to severe impairments in everyday life, which can further influence the social and mental state. For these reasons, early developments in cosmetic and body-driven prostheses date some centuries ago, and they have been evolving ever since. Following the end of the Second World War, rapid developments in technology resulted in powered myoelectric hand prosthetics. In the years to come, these devices were common on the market, though they still suffered high user abandonment rates. The reasons for rejection were trifold – insufficient functionality of the hardware, fragile design, and cumbersome control. In the last decade, both academia and industry have reached major improvements concerning technical features of upper limb prosthetics and methods for their interfacing and control. Advanced robotic hands are offered by several vendors and research groups, with a variety of active and passive wrist options that can be articulated across several degrees of freedom. Nowadays, elbow joint designs include active solutions with different weight and power options. Control features are getting progressively more sophisticated, offering options for multiple sensor integration and multi-joint articulation. Latest developments in socket designs are capable of facilitating implantable and multiple surface electromyography sensors in both traditional and osseointegration-based systems. Novel surgical techniques in combination with modern, sophisticated hardware are enabling restoration of dexterous upper limb

Assessment of Myoelectric Controller Performance and Kinematic Behavior of a Novel Soft Synergy-Inspired Robotic Hand for Prosthetic Applications.

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Fani, Simone; Bianchi, Matteo; Jain, Sonal; Pimenta Neto, José Simões; Boege, Scott; Grioli, Giorgio; Bicchi, Antonio; Santello, Marco

2016-01-01

Myoelectric artificial limbs can significantly advance the state of the art in prosthetics, since they can be used to control mechatronic devices through muscular activity in a way that mimics how the subjects used to activate their muscles before limb loss. However, surveys indicate that dissatisfaction with the functionality of terminal devices underlies the widespread abandonment of prostheses. We believe that one key factor to improve acceptability of prosthetic devices is to attain human likeness of prosthesis movements, a goal which is being pursued by research on social and human-robot interactions. Therefore, to reduce early abandonment of terminal devices, we propose that controllers should be designed so as to ensure effective task accomplishment in a natural fashion. In this work, we have analyzed and compared the performance of three types of myoelectric controller algorithms based on surface electromyography to control an underactuated and multi-degrees of freedom prosthetic hand, the SoftHand Pro. The goal of the present study was to identify the myoelectric algorithm that best mimics the native hand movements. As a preliminary step, we first quantified the repeatability of the SoftHand Pro finger movements and identified the electromyographic recording sites for able-bodied individuals with the highest signal-to-noise ratio from two pairs of muscles, i.e., flexor digitorum superficialis/extensor digitorum communis, and flexor carpi radialis/extensor carpi ulnaris. Able-bodied volunteers were then asked to execute reach-to-grasp movements, while electromyography signals were recorded from flexor digitorum superficialis/extensor digitorum communis as this was identified as the muscle pair characterized by high signal-to-noise ratio and intuitive control. Subsequently, we tested three myoelectric controllers that mapped electromyography signals to position of the SoftHand Pro. We found that a differential electromyography-to-position mapping ensured the

Assessment of Myoelectric Controller Performance and Kinematic Behavior of a Novel Soft Synergy-inspired Robotic Hand for Prosthetic Applications

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Simone Fani

2016-10-01

Full Text Available Myoelectric-artificial limbs can significantly advance the state of the art in prosthetics, since they can be used to control mechatronic devices through muscular activity in a way that mimics how the subjects used to activate their muscles before limb loss. However, surveys indicate that dissatisfaction with the functionality of terminal devices underlies the widespread abandonment of prostheses. We believe that one key factor to improve acceptability of prosthetic devices is to attain human-likeness of prosthesis movements, a goal which is being pursued by research on social and human-robot interactions. Therefore, to reduce early abandonment of terminal devices, we propose that controllers should be designed such as to ensure effective task accomplishment in a natural fashion. In this work, we have analyzed and compared the performance of three types of myoelectric controller algorithms based on surface electromyography to control an under-actuated and multi-degrees of freedom prosthetic hand, the SoftHand Pro. The goal of the present study was to identify the myoelectric algorithm that best mimics the native hand movements. As a preliminary step, we first quantified the repeatability of the SoftHand Pro finger movements and identified the electromyographic recording sites for able-bodied individuals with the highest signal-to-noise ratio from two pairs of muscles, i.e. flexor digitorum superficialis/extensor digitorum communis, and flexor carpi radialis/extensor carpi ulnaris. Able-bodied volunteers were then asked to execute reach-to-grasp movements, while electromyography signals were recorded from flexor digitorum superficialis/extensor digitorum communis as this was identified as the muscle pair characterized by high signal-to-noise ratio and intuitive control. Subsequently, we tested three myoelectric controllers that mapped electromyography signals to position of the SoftHand Pro. We found that a differential electromyography

Recognizing the Operating Hand and the Hand-Changing Process for User Interface Adjustment on Smartphones.

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Guo, Hansong; Huang, He; Huang, Liusheng; Sun, Yu-E

2016-08-20

As the size of smartphone touchscreens has become larger and larger in recent years, operability with a single hand is getting worse, especially for female users. We envision that user experience can be significantly improved if smartphones are able to recognize the current operating hand, detect the hand-changing process and then adjust the user interfaces subsequently. In this paper, we proposed, implemented and evaluated two novel systems. The first one leverages the user-generated touchscreen traces to recognize the current operating hand, and the second one utilizes the accelerometer and gyroscope data of all kinds of activities in the user's daily life to detect the hand-changing process. These two systems are based on two supervised classifiers constructed from a series of refined touchscreen trace, accelerometer and gyroscope features. As opposed to existing solutions that all require users to select the current operating hand or confirm the hand-changing process manually, our systems follow much more convenient and practical methods and allow users to change the operating hand frequently without any harm to the user experience. We conduct extensive experiments on Samsung Galaxy S4 smartphones, and the evaluation results demonstrate that our proposed systems can recognize the current operating hand and detect the hand-changing process with 94.1% and 93.9% precision and 94.1% and 93.7% True Positive Rates (TPR) respectively, when deciding with a single touchscreen trace or accelerometer-gyroscope data segment, and the False Positive Rates (FPR) are as low as 2.6% and 0.7% accordingly. These two systems can either work completely independently and achieve pretty high accuracies or work jointly to further improve the recognition accuracy.

Prosthetic finger phalanges with lifelike skin compliance for low-force social touching interactions

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Ge Shuzhi

2011-03-01

Full Text Available Abstract Background Prosthetic arms and hands that can be controlled by the user's electromyography (EMG signals are emerging. Eventually, these advanced prosthetic devices will be expected to touch and be touched by other people. As realistic as they may look, the currently available prosthetic hands have physical properties that are still far from the characteristics of human skins because they are much stiffer. In this paper, different configurations of synthetic finger phalanges have been investigated for their skin compliance behaviour and have been compared with the phalanges of the human fingers and a phalanx from a commercially available prosthetic hand. Methods Handshake tests were performed to identify which areas on the human hand experience high contact forces. After these areas were determined, experiments were done on selected areas using an indenting probe to obtain the force-displacement curves. Finite element simulations were used to compare the force-displacement results of the synthetic finger phalanx designs with that of the experimental results from the human and prosthetic finger phalanges. The simulation models were used to investigate the effects of (a varying the internal topology of the finger phalanx and (b varying different materials for the internal and external layers. Results and Conclusions During handshake, the high magnitudes of contact forces were observed at the areas where the full grasping enclosure of the other person's hand can be achieved. From these areas, the middle phalanges of the (a little, (b ring, and (c middle fingers were selected. The indentation experiments on these areas showed that a 2 N force corresponds to skin tissue displacements of more than 2 mm. The results from the simulation model show that introducing an open pocket with 2 mm height on the internal structure of synthetic finger phalanges increased the skin compliance of the silicone material to 235% and the polyurethane material to

Recognizing the Operating Hand and the Hand-Changing Process for User Interface Adjustment on Smartphones

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Hansong Guo

2016-08-01

Full Text Available As the size of smartphone touchscreens has become larger and larger in recent years, operability with a single hand is getting worse, especially for female users. We envision that user experience can be significantly improved if smartphones are able to recognize the current operating hand, detect the hand-changing process and then adjust the user interfaces subsequently. In this paper, we proposed, implemented and evaluated two novel systems. The first one leverages the user-generated touchscreen traces to recognize the current operating hand, and the second one utilizes the accelerometer and gyroscope data of all kinds of activities in the user’s daily life to detect the hand-changing process. These two systems are based on two supervised classifiers constructed from a series of refined touchscreen trace, accelerometer and gyroscope features. As opposed to existing solutions that all require users to select the current operating hand or confirm the hand-changing process manually, our systems follow much more convenient and practical methods and allow users to change the operating hand frequently without any harm to the user experience. We conduct extensive experiments on Samsung Galaxy S4 smartphones, and the evaluation results demonstrate that our proposed systems can recognize the current operating hand and detect the hand-changing process with 94.1% and 93.9% precision and 94.1% and 93.7% True Positive Rates (TPR respectively, when deciding with a single touchscreen trace or accelerometer-gyroscope data segment, and the False Positive Rates (FPR are as low as 2.6% and 0.7% accordingly. These two systems can either work completely independently and achieve pretty high accuracies or work jointly to further improve the recognition accuracy.

User Interface Aspects of a Human-Hand Simulation System

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Beifang Yi

2005-10-01

Full Text Available This paper describes the user interface design for a human-hand simulation system, a virtual environment that produces ground truth data (life-like human hand gestures and animations and provides visualization support for experiments on computer vision-based hand pose estimation and tracking. The system allows users to save time in data generation and easily create any hand gestures. We have designed and implemented this user interface with the consideration of usability goals and software engineering issues.

Golf hand prosthesis performance of transradial amputees.

Science.gov (United States)

Carey, Stephanie L; Wernke, Matthew M; Lura, Derek J; Kahle, Jason T; Dubey, Rajiv V; Highsmith, M Jason

2015-06-01

Typical upper limb prostheses may limit sports participation; therefore, specialized terminal devices are often needed. The purpose of this study was to evaluate the ability of transradial amputees to play golf using a specialized terminal device. Club head speed, X-factor, and elbow motion of two individuals with transradial amputations using an Eagle Golf terminal device were compared to a non-amputee during a golf swing. Measurements were collected pre/post training with various stances and grips. Both prosthesis users preferred a right-handed stance initially; however, after training, one preferred a left-handed stance. The amputees had slower club head speeds and a lower X-factor compared to the non-amputee golfer, but increased their individual elbow motion on the prosthetic side after training. Amputees enjoyed using the device, and it may provide kinematic benefits indicated by the increase in elbow flexion on the prosthetic side. The transradial amputees were able to swing a golf club with sufficient repetition, form, and velocity to play golf recreationally. Increased elbow flexion on the prosthetic side suggests a potential benefit from using the Eagle Golf terminal device. Participating in recreational sports can increase amputees' health and quality of life. © The International Society for Prosthetics and Orthotics 2014.

Recognizing the Operating Hand and the Hand-Changing Process for User Interface Adjustment on Smartphones †

Science.gov (United States)

Guo, Hansong; Huang, He; Huang, Liusheng; Sun, Yu-E

2016-01-01

As the size of smartphone touchscreens has become larger and larger in recent years, operability with a single hand is getting worse, especially for female users. We envision that user experience can be significantly improved if smartphones are able to recognize the current operating hand, detect the hand-changing process and then adjust the user interfaces subsequently. In this paper, we proposed, implemented and evaluated two novel systems. The first one leverages the user-generated touchscreen traces to recognize the current operating hand, and the second one utilizes the accelerometer and gyroscope data of all kinds of activities in the user’s daily life to detect the hand-changing process. These two systems are based on two supervised classifiers constructed from a series of refined touchscreen trace, accelerometer and gyroscope features. As opposed to existing solutions that all require users to select the current operating hand or confirm the hand-changing process manually, our systems follow much more convenient and practical methods and allow users to change the operating hand frequently without any harm to the user experience. We conduct extensive experiments on Samsung Galaxy S4 smartphones, and the evaluation results demonstrate that our proposed systems can recognize the current operating hand and detect the hand-changing process with 94.1% and 93.9% precision and 94.1% and 93.7% True Positive Rates (TPR) respectively, when deciding with a single touchscreen trace or accelerometer-gyroscope data segment, and the False Positive Rates (FPR) are as low as 2.6% and 0.7% accordingly. These two systems can either work completely independently and achieve pretty high accuracies or work jointly to further improve the recognition accuracy. PMID:27556461

Identification of motion from multi-channel EMG signals for control of prosthetic hand

International Nuclear Information System (INIS)

Geethanjali, P.; Ray, K.K.

2011-01-01

Full text: The authors in this paper propose an effective and efficient pattern recognition technique from four channel electromyogram (EMG) signals for control of multifunction prosthetic hand. Time domain features such as mean absolute value, number of zero crossings, number of slope sign changes and waveform length are considered for pattern recognition. The patterns are classified using simple logistic regression (SLR) technique and decision tree (DT) using J48 algorithm. In this study six specific hand and wrist motions are identified from the EMG signals obtained from ten different able-bodied. By considering relevant dominant features for pattern recognition, the processing time as well as memory space of the SLR and DT classifiers is found to be less in comparison with neural network (NN), k-nearest neighbour model 1 (kNN Model-1), k-nearest neighbour model 2 (kNN-Model-2) and linear discriminant analysis. The classification accuracy of SLR classifier is found to be 91 ± 1.9%. (author)

Human-Machine Interface for the Control of Multi-Function Systems Based on Electrocutaneous Menu: Application to Multi-Grasp Prosthetic Hands.

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Jose Gonzalez-Vargas

Full Text Available Modern assistive devices are very sophisticated systems with multiple degrees of freedom. However, an effective and user-friendly control of these systems is still an open problem since conventional human-machine interfaces (HMI cannot easily accommodate the system's complexity. In HMIs, the user is responsible for generating unique patterns of command signals directly triggering the device functions. This approach can be difficult to implement when there are many functions (necessitating many command patterns and/or the user has a considerable impairment (limited number of available signal sources. In this study, we propose a novel concept for a general-purpose HMI where the controller and the user communicate bidirectionally to select the desired function. The system first presents possible choices to the user via electro-tactile stimulation; the user then acknowledges the desired choice by generating a single command signal. Therefore, the proposed approach simplifies the user communication interface (one signal to generate, decoding (one signal to recognize, and allows selecting from a number of options. To demonstrate the new concept the method was used in one particular application, namely, to implement the control of all the relevant functions in a state of the art commercial prosthetic hand without using any myoelectric channels. We performed experiments in healthy subjects and with one amputee to test the feasibility of the novel approach. The results showed that the performance of the novel HMI concept was comparable or, for some outcome measures, better than the classic myoelectric interfaces. The presented approach has a general applicability and the obtained results point out that it could be used to operate various assistive systems (e.g., prosthesis vs. wheelchair, or it could be integrated into other control schemes (e.g., myoelectric control, brain-machine interfaces in order to improve the usability of existing low

Human-Machine Interface for the Control of Multi-Function Systems Based on Electrocutaneous Menu: Application to Multi-Grasp Prosthetic Hands.

Science.gov (United States)

Gonzalez-Vargas, Jose; Dosen, Strahinja; Amsuess, Sebastian; Yu, Wenwei; Farina, Dario

2015-01-01

Modern assistive devices are very sophisticated systems with multiple degrees of freedom. However, an effective and user-friendly control of these systems is still an open problem since conventional human-machine interfaces (HMI) cannot easily accommodate the system's complexity. In HMIs, the user is responsible for generating unique patterns of command signals directly triggering the device functions. This approach can be difficult to implement when there are many functions (necessitating many command patterns) and/or the user has a considerable impairment (limited number of available signal sources). In this study, we propose a novel concept for a general-purpose HMI where the controller and the user communicate bidirectionally to select the desired function. The system first presents possible choices to the user via electro-tactile stimulation; the user then acknowledges the desired choice by generating a single command signal. Therefore, the proposed approach simplifies the user communication interface (one signal to generate), decoding (one signal to recognize), and allows selecting from a number of options. To demonstrate the new concept the method was used in one particular application, namely, to implement the control of all the relevant functions in a state of the art commercial prosthetic hand without using any myoelectric channels. We performed experiments in healthy subjects and with one amputee to test the feasibility of the novel approach. The results showed that the performance of the novel HMI concept was comparable or, for some outcome measures, better than the classic myoelectric interfaces. The presented approach has a general applicability and the obtained results point out that it could be used to operate various assistive systems (e.g., prosthesis vs. wheelchair), or it could be integrated into other control schemes (e.g., myoelectric control, brain-machine interfaces) in order to improve the usability of existing low-bandwidth HMIs.

Interface Prostheses With Classifier-Feedback-Based User Training.

Science.gov (United States)

Fang, Yinfeng; Zhou, Dalin; Li, Kairu; Liu, Honghai

2017-11-01

It is evident that user training significantly affects performance of pattern-recognition-based myoelectric prosthetic device control. Despite plausible classification accuracy on offline datasets, online accuracy usually suffers from the changes in physiological conditions and electrode displacement. The user ability in generating consistent electromyographic (EMG) patterns can be enhanced via proper user training strategies in order to improve online performance. This study proposes a clustering-feedback strategy that provides real-time feedback to users by means of a visualized online EMG signal input as well as the centroids of the training samples, whose dimensionality is reduced to minimal number by dimension reduction. Clustering feedback provides a criterion that guides users to adjust motion gestures and muscle contraction forces intentionally. The experiment results have demonstrated that hand motion recognition accuracy increases steadily along the progress of the clustering-feedback-based user training, while conventional classifier-feedback methods, i.e., label feedback, hardly achieve any improvement. The result concludes that the use of proper classifier feedback can accelerate the process of user training, and implies prosperous future for the amputees with limited or no experience in pattern-recognition-based prosthetic device manipulation.It is evident that user training significantly affects performance of pattern-recognition-based myoelectric prosthetic device control. Despite plausible classification accuracy on offline datasets, online accuracy usually suffers from the changes in physiological conditions and electrode displacement. The user ability in generating consistent electromyographic (EMG) patterns can be enhanced via proper user training strategies in order to improve online performance. This study proposes a clustering-feedback strategy that provides real-time feedback to users by means of a visualized online EMG signal input as well

User interface for a tele-operated robotic hand system

Science.gov (United States)

Crawford, Anthony L

2015-03-24

Disclosed here is a user interface for a robotic hand. The user interface anchors a user's palm in a relatively stationary position and determines various angles of interest necessary for a user's finger to achieve a specific fingertip location. The user interface additionally conducts a calibration procedure to determine the user's applicable physiological dimensions. The user interface uses the applicable physiological dimensions and the specific fingertip location, and treats the user's finger as a two link three degree-of-freedom serial linkage in order to determine the angles of interest. The user interface communicates the angles of interest to a gripping-type end effector which closely mimics the range of motion and proportions of a human hand. The user interface requires minimal contact with the operator and provides distinct advantages in terms of available dexterity, work space flexibility, and adaptability to different users.

A user-specific human-machine interaction strategy for a prosthetic shank adapter

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Stuhlenmiller Florian

2017-09-01

Full Text Available For people with lower limb amputation, a user-specific human-machine interaction with their prostheses is required to ensure safe and comfortable assistance. Especially during dynamic turning manoeuvres, users experience high loads at the stump, which decreases comfort and may lead to long-term tissue damage. Preliminary experiments with users wearing a configurable, passive torsional adaptor indicate increased comfort and safety achieved by adaptation of torsional stiffness and foot alignment. Moreover, the results show that the individual preference regarding both parameters depend on gait situation and individual preference. Hence, measured loads in the structure of the prosthesis and subjective feedback regarding comfort and safety during different turning motions are considered in a user-specific human-machine interaction strategy for a prosthetic shank adaptor. Therefore, the interrelations of gait parameters with optimal configuration are stored in an individual preference-setting matrix. Stiffness and foot alignment are actively adjusted to the optimal parameters by a parallel elastic actuator. Two subjects reported that they experienced appropriate variation of stiffness and foot alignment, a noticeable reduction of load at the stump and that they could turn with less effort.

User interface for a tele-operated robotic hand system

Energy Technology Data Exchange (ETDEWEB)

Crawford, Anthony L

2015-03-24

Disclosed here is a user interface for a robotic hand. The user interface anchors a user's palm in a relatively stationary position and determines various angles of interest necessary for a user's finger to achieve a specific fingertip location. The user interface additionally conducts a calibration procedure to determine the user's applicable physiological dimensions. The user interface uses the applicable physiological dimensions and the specific fingertip location, and treats the user's finger as a two link three degree-of-freedom serial linkage in order to determine the angles of interest. The user interface communicates the angles of interest to a gripping-type end effector which closely mimics the range of motion and proportions of a human hand. The user interface requires minimal contact with the operator and provides distinct advantages in terms of available dexterity, work space flexibility, and adaptability to different users.

Image segmentation for enhancing symbol recognition in prosthetic vision.

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Horne, Lachlan; Barnes, Nick; McCarthy, Chris; He, Xuming

2012-01-01

Current and near-term implantable prosthetic vision systems offer the potential to restore some visual function, but suffer from poor resolution and dynamic range of induced phosphenes. This can make it difficult for users of prosthetic vision systems to identify symbolic information (such as signs) except in controlled conditions. Using image segmentation techniques from computer vision, we show it is possible to improve the clarity of such symbolic information for users of prosthetic vision implants in uncontrolled conditions. We use image segmentation to automatically divide a natural image into regions, and using a fixation point controlled by the user, select a region to phosphenize. This technique improves the apparent contrast and clarity of symbolic information over traditional phosphenization approaches.

Is the Prosthetic Homologue Necessary for Embodiment?

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Dornfeld, Chelsea; Swanston, Michelle; Cassella, Joseph; Beasley, Casey; Green, Jacob; Moshayev, Yonatan; Wininger, Michael

2016-01-01

Embodiment is the process by which patients with limb loss come to accept their peripheral device as a natural extension of self. However, there is little guidance as to how exacting the prosthesis must be in order for embodiment to take place: is it necessary for the prosthetic hand to look just like the absent hand? Here, we describe a protocol for testing whether an individual would select a hand that looks like their own from among a selection of five hands, and whether the hand selection (regardless of homology) is consistent across multiple exposures to the same (but reordered) set of candidate hands. Pilot results using healthy volunteers reveals that hand selection is only modestly consistent, and that selection of the prosthetic homologue is atypical (61 of 192 total exposures). Our protocol can be executed in minutes, and makes use of readily available equipment and softwares. We present both a face-to-face and a virtual protocol, for maximum flexibility of implementation.

Embodied prosthetic arm stabilizes body posture, while unembodied one perturbs it.

Science.gov (United States)

Imaizumi, Shu; Asai, Tomohisa; Koyama, Shinichi

2016-10-01

Senses of ownership (this arm belongs to me) and agency (I am controlling this arm) originate from sensorimotor system. External objects can be integrated into the sensorimotor system following long-term use, and recognized as one's own body. We examined how an (un)embodied prosthetic arm modulates whole-body control, and assessed the components of prosthetic embodiment. Nine unilateral upper-limb amputees participated. Four frequently used their prosthetic arm, while the others rarely did. Their postural sway was measured during quiet standing with or without their prosthesis. The frequent users showed greater sway when they removed the prosthesis, while the rare users showed greater sway when they fitted the prosthesis. Frequent users reported greater everyday feelings of postural stabilization by prosthesis and a larger sense of agency over the prosthesis. We suggest that a prosthetic arm maintains or perturbs postural control, depending on the prosthetic embodiment, which involves sense of agency rather than ownership. Copyright © 2016 Elsevier Inc. All rights reserved.

Case-study of a user-driven prosthetic arm design: bionic hand versus customized body-powered technology in a highly demanding work environment.

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Schweitzer, Wolf; Thali, Michael J; Egger, David

2018-01-03

Prosthetic arm research predominantly focuses on "bionic" but not body-powered arms. However, any research orientation along user needs requires sufficiently precise workplace specifications and sufficiently hard testing. Forensic medicine is a demanding environment, also physically, also for non-disabled people, on several dimensions (e.g., distances, weights, size, temperature, time). As unilateral below elbow amputee user, the first author is in a unique position to provide direct comparison of a "bionic" myoelectric iLimb Revolution (Touch Bionics) and a customized body-powered arm which contains a number of new developments initiated or developed by the user: (1) quick lock steel wrist unit; (2) cable mount modification; (3) cast shape modeled shoulder anchor; (4) suspension with a soft double layer liner (Ohio Willowwood) and tube gauze (Molnlycke) combination. The iLimb is mounted on an epoxy socket; a lanyard fixed liner (Ohio Willowwood) contains magnetic electrodes (Liberating Technologies). An on the job usage of five years was supplemented with dedicated and focused intensive two-week use tests at work for both systems. The side-by-side comparison showed that the customized body-powered arm provides reliable, comfortable, effective, powerful as well as subtle service with minimal maintenance; most notably, grip reliability, grip force regulation, grip performance, center of balance, component wear down, sweat/temperature independence and skin state are good whereas the iLimb system exhibited a number of relevant serious constraints. Research and development of functional prostheses may want to focus on body-powered technology as it already performs on manually demanding and heavy jobs whereas eliminating myoelectric technology's constraints seems out of reach. Relevant testing could be developed to help expediting this. This is relevant as Swiss disability insurance specifically supports prostheses that enable actual work integration. Myoelectric and

Design and fabrication of a three-finger prosthetic hand using SMA muscle wires

Science.gov (United States)

Simone, Filomena; York, Alexander; Seelecke, Stefan

2015-03-01

Bio-inspired hand-like gripper systems based on shape memory alloy (SMA) wire actuation have the potential to enable a number of useful applications in, e.g., the biomedical field or industrial assembly systems. The inherent high energy density makes SMA solutions a natural choice for systems with lightweight, low noise and high force requirements, such as hand prostheses or robotic systems in a human/machine environment. The focus of this research is the development, design and realization of a SMA-actuated prosthetic hand prototype with three fingers. The use of thin wires (100 μm diameter) allows for high cooling rates and therefore fast movement of each finger. Grouping several small wires mechanically in parallel allows for high force actuation. To save space and to allow for a direct transmission of the motion to each finger, the SMA wires are attached directly within each finger, across each phalanx. In this way, the contraction of the wires will allow the movement of the fingers without the use of any additional gears. Within each finger, two different bundles of wires are mounted: protagonist ones that create bending movement and the antagonist ones that enable stretching of each phalanx. The resistance change in the SMA wires is measured during actuation, which allows for monitoring of the wire stroke and potentially the gripping force without the use of additional sensors. The hand is built with modern 3D-printing technologies and its performance while grasping objects of different size and shape is experimentally investigated illustrating the usefulness of the actuator concept.

Effects of prosthetic foot forefoot flexibility on oxygen cost and subjective preference rankings of unilateral transtibial prosthesis users.

Science.gov (United States)

Klodd, Elizabeth; Hansen, Andrew; Fatone, Stefania; Edwards, Mark

2010-01-01

The investigators conducted a double-blind randomized crossover study to determine the effects of prosthetic foot forefoot flexibility on oxygen cost and subjective preference rankings of 13 unilateral transtibial prosthesis users. Five experimental feet were fabricated for use in the study: F1, F2, F3, F4, and F5. F1 was most flexible, F5 was least flexible, and F3 was designed to conform to a biomimetic ankle-foot roll-over shape. The experimental feet were modeled after the Shape&Roll prosthetic foot (originally produced by Northwestern University, Chicago, Illinois; now in public domain) but had different numbers of saw cuts within the forefoot members, allowing more or less flexibility during walking. Participants walked at the same comfortable, freely selected speed on the treadmill for 7 min with each foot while energy expenditure was measured. No significant difference was found in oxygen cost (mL O(2)/kg/m) between the different feet (p = 0.17), and the order of use was also not significant (p = 0.94). However, the preference ranking was significantly affected by the flexibility of the feet (p = 0.002), with the most flexible foot (F1) ranking significantly poorer than feet F3 (p = 0.003) and F4 (p = 0.004). Users may prefer prosthetic feet that match the flexibility of an intact ankle-foot system, even though we did not detect an energetic benefit at freely selected speeds.

Optimising the prescription of prosthetic technologies (opptec): Outcome measures for evidence based prosthetic practice and use

LENUS (Irish Health Repository)

Ryall, Dr Nicola

2010-01-01

This study provided a forum for patients and service providers to voice their opinions in what they believe to be the important predictors and outcomes involved in successful rehabilitation following limb loss. To develop a consensus on the most important outcomes and factors to address for both the lower limb and upper limb prosthetic prescription process, the above data relating to lower limb and upper prosthetics were subsequently used in the next phase of the research involving two Delphi surveys of 23 and 53 experts within the lower limb and upper limb amputation and prosthetic field respectively, including users, service providers and researchers.\\r\

Effects of a flat prosthetic foot rocker section on balance and mobility.

Science.gov (United States)

Hansen, Andrew; Nickel, Eric; Medvec, Joseph; Brielmaier, Steven; Pike, Alvin; Weber, Marilyn

2014-01-01

Previous studies have shown that the effective rocker shape of the physiologic ankle-foot system during standing and fore-aft swaying is much flatter than that used during walking, which indicates a more stable base of support for the standing/swaying activity. Previous work suggests that flat regions within the effective rocker shapes of prosthetic ankle-foot systems could provide enhanced stability for standing balance tasks. An experimental prosthetic foot was altered to provide three different flat region lengths within its effective rocker shape. It was hypothesized that longer flat regions of the effective rocker shape would lead to improved standing balance outcomes and reduced walking performance for unilateral transtibial prosthesis users. However, no significant changes were seen in the balance and mobility outcomes of 12 unilateral transtibial prosthesis users when using the three prosthetic foot conditions. Subjects in the study significantly preferred prosthetic feet with relatively low to moderate flat regions over those with long flat regions. All the subjects without loss of light touch or vibratory sensation selected the prosthetic foot with the shortest flat region. More work is needed to investigate the effects of prosthetic foot properties on balance and mobility of prosthesis users.

Closed-loop control of grasping with a myoelectric hand prosthesis: which are the relevant feedback variables for force control?

Science.gov (United States)

Ninu, Andrei; Dosen, Strahinja; Muceli, Silvia; Rattay, Frank; Dietl, Hans; Farina, Dario

2014-09-01

In closed-loop control of grasping by hand prostheses, the feedback information sent to the user is usually the actual controlled variable, i.e., the grasp force. Although this choice is intuitive and logical, the force production is only the last step in the process of grasping. Therefore, this study evaluated the performance in controlling grasp strength using a hand prosthesis operated through a complete grasping sequence while varying the feedback variables (e.g., closing velocity, grasping force), which were provided to the user visually or through vibrotactile stimulation. The experiments were conducted on 13 volunteers who controlled the Otto Bock Sensor Hand Speed prosthesis. Results showed that vibrotactile patterns were able to replace the visual feedback. Interestingly, the experiments demonstrated that direct force feedback was not essential for the control of grasping force. The subjects were indeed able to control the grip strength, predictively, by estimating the grasping force from the prosthesis velocity of closing. Therefore, grasping without explicit force feedback is not completely blind, contrary to what is usually assumed. In our study we analyzed grasping with a specific prosthetic device, but the outcomes are also applicable for other devices, with one or more degrees-of-freedom. The necessary condition is that the electromyography (EMG) signal directly and proportionally controls the velocity/grasp force of the hand, which is a common approach among EMG controlled prosthetic devices. The results provide important indications on the design of closed-loop EMG controlled prosthetic systems.

Methodology for designing and manufacturing complex biologically inspired soft robotic fluidic actuators: prosthetic hand case study.

Science.gov (United States)

Thompson-Bean, E; Das, R; McDaid, A

2016-10-31

We present a novel methodology for the design and manufacture of complex biologically inspired soft robotic fluidic actuators. The methodology is applied to the design and manufacture of a prosthetic for the hand. Real human hands are scanned to produce a 3D model of a finger, and pneumatic networks are implemented within it to produce a biomimetic bending motion. The finger is then partitioned into material sections, and a genetic algorithm based optimization, using finite element analysis, is employed to discover the optimal material for each section. This is based on two biomimetic performance criteria. Two sets of optimizations using two material sets are performed. Promising optimized material arrangements are fabricated using two techniques to validate the optimization routine, and the fabricated and simulated results are compared. We find that the optimization is successful in producing biomimetic soft robotic fingers and that fabrication of the fingers is possible. Limitations and paths for development are discussed. This methodology can be applied for other fluidic soft robotic devices.

Upper Limb-Hand 3D Display System for Biomimetic Myoelectric Hand Simulator

National Research Council Canada - National Science Library

Jimenez, Gonzalo

2001-01-01

A graphics system displaying both upper limb posture and opening-closing of a prosthetic hand was developed for realtime operation of our biomimetic myoelectric hand simulator, Posture of the upper...

Fused Filament Fabrication of Prosthetic Components for Trans-Humeral Upper Limb Prosthetics

Science.gov (United States)

Lathers, Steven M.

Presented below is the design and fabrication of prosthetic components consisting of an attachment, tactile sensing, and actuator systems with Fused Filament Fabrication (FFF) technique. The attachment system is a thermoplastic osseointegrated upper limb prosthesis for average adult trans-humeral amputation with mechanical properties greater than upper limb skeletal bone. The prosthetic designed has: a one-step surgical process, large cavities for bone tissue ingrowth, uses a material that has an elastic modulus less than skeletal bone, and can be fabricated on one system. FFF osseointegration screw is an improvement upon the current two-part osseointegrated prosthetics that are composed of a fixture and abutment. The current prosthetic design requires two invasive surgeries for implantation and are made of titanium, which has an elastic modulus greater than bone. An elastic modulus greater than bone causes stress shielding and overtime can cause loosening of the prosthetic. The tactile sensor is a thermoplastic piezo-resistive sensor for daily activities for a prosthetic's feedback system. The tactile sensor is manufactured from a low elastic modulus composite comprising of a compressible thermoplastic elastomer and conductive carbon. Carbon is in graphite form and added in high filler ratios. The printed sensors were compared to sensors that were fabricated in a gravity mold to highlight the difference in FFF sensors to molded sensors. The 3D printed tactile sensor has a thickness and feel similar to human skin, has a simple fabrication technique, can detect forces needed for daily activities, and can be manufactured in to user specific geometries. Lastly, a biomimicking skeletal muscle actuator for prosthetics was developed. The actuator developed is manufactured with Fuse Filament Fabrication using a shape memory polymer composite that has non-linear contractile and passive forces, contractile forces and strains comparable to mammalian skeletal muscle, reaction

Surface EMG and intra-socket force measurement to control a prosthetic device

Science.gov (United States)

Sanford, Joe; Patterson, Rita; Popa, Dan

2015-06-01

Surface electromyography (SEMG) has been shown to be a robust and reliable interaction method allowing for basic control of powered prosthetic devices. Research has shown a marked decrease in EMG-classification efficiency throughout activities of daily life due to socket shift and movement and fatigue as well as changes in degree of fit of the socket throughout the subject's lifetime. Users with the most severe levels of amputation require the most complex devices with the greatest number of degrees of freedom. Controlling complex dexterous devices with limited available inputs requires the addition of sensing and interaction modalities. However, the larger the amputation severity, the fewer viable SEMG sites are available as control inputs. Previous work reported the use of intra-socket pressure, as measured during wrist flexion and extension, and has shown that it is possible to control a powered prosthetic device with pressure sensors. In this paper, we present data correlations of SEMG data with intra-socket pressure data. Surface EMG sensors and force sensors were housed within a simulated prosthetic cuff fit to a healthy-limbed subject. EMG and intra-socket force data was collected from inside the cuff as a subject performed pre-defined grip motions with their dominant hand. Data fusion algorithms were explored and allowed a subject to use both intra-socket pressure and SEMG data as control inputs for a powered prosthetic device. This additional input modality allows for an improvement in input classification as well as information regarding socket fit through out activities of daily life.

Effects of prosthetic foot forefoot flexibility on oxygen cost and subjective preference rankings of unilateral transtibial prosthesis users

OpenAIRE

Mark Edwards, MHPE, CP; Stefania Fatone, PhD; Andrew Hansen, PhD; Elizabeth Klodd, MS

2010-01-01

The investigators conducted a double-blind randomized crossover study to determine the effects of prosthetic foot forefoot flexibility on oxygen cost and subjective preference rankings of 13 unilateral transtibial prosthesis users. Five experimental feet were fabricated for use in the study: F1, F2, F3, F4, and F5. F1 was most flexible, F5 was least flexible, and F3 was designed to conform to a biomimetic ankle-foot roll-over shape. The experimental feet were modeled after the Shape&Roll pros...

User evaluation of patient counselling, combining nurse consultation and eHealth in hand eczema

DEFF Research Database (Denmark)

Mollerup, Annette; Harboe, Gitte; Johansen, Jeanne D

2016-01-01

BACKGROUND AND OBJECTIVE: This study reports the findings from a user evaluation of a counselling programme for hand eczema patients in which face-to-face encounters were supplemented with user access to a new website. PATIENTS AND METHODS: Patients treated for hand eczema in two different settin...

The nonvisual illusion of self-touch: Misaligned hands and anatomical implausibility.

Science.gov (United States)

White, Rebekah C; Weinberg, Jennifer L; Aimola Davies, Anne M

2015-01-01

The self-touch illusion is elicited when the participant (with eyes closed) administers brushstrokes to a prosthetic hand while the examiner administers synchronous brushstrokes to the participant's other (receptive) hand. In three experiments we investigated the effects of misalignment on the self-touch illusion. In experiment 1 we manipulated alignment (0 degrees, 45 degrees, 90 degrees, 135 degrees, 180 degrees) of the prosthetic hand relative to the participant's receptive hand. The illusion was equally strong at 0 degrees and 45 degrees: the two conditions in which the prosthetic hand was in an anatomically plausible orientation. To investigate whether the illusion was diminished at 90 degrees (and beyond) by anatomical implausibility rather than by misalignment, in experiment 2 hand positioning was changed. The illusion was equally strong at 0 degrees, 45 degrees, and 90 degrees, but diminished at 135 degrees despite the prosthetic hand now being in an anatomically plausible orientation. Thus the illusion is diminished with misalignment of 135 degrees, irrespective of anatomical plausibility. Having demonstrated that the illusion was equally strong with the hands aligned (0 degrees) or misaligned by 45 degrees, in experiment 3 we demonstrated that participants did not detect a 45 degrees misalignment. Large degrees of misalignment prevent a compelling experience of the self-touch illusion, and the self-touch illusion prevents detection of small degrees of misalignment.

The effects of common footwear on stance-phase mechanical properties of the prosthetic foot-shoe system.

Science.gov (United States)

Major, Matthew J; Scham, Joel; Orendurff, Michael

2018-04-01

Prosthetic feet are prescribed based on their mechanical function and user functional level. Subtle changes to the stiffness and hysteresis of heel, midfoot, and forefoot regions can influence the dynamics and economy of gait in prosthesis users. However, the user's choice of shoes may alter the prosthetic foot-shoe system mechanical characteristics, compromising carefully prescribed and rigorously engineered performance of feet. Observe the effects of footwear on the mechanical properties of the prosthetic foot-shoe system including commonly prescribed prosthetic feet. Repeated-measures, Mechanical characterization. The stiffness and energy return was measured using a hydraulic-driven materials test machine across combinations of five prosthetic feet and four common shoes as well as a barefoot condition. Heel energy return decreased by an average 4%-9% across feet in all shoes compared to barefoot, with a cushioned trainer displaying the greatest effect. Foot designs that may improve perceived stability by providing low heel stiffness and rapid foot-flat were compromised by the addition of shoes. Shoes altered prosthesis mechanical characteristics in the sagittal and frontal planes, suggesting that shoe type should be controlled or reported in research comparing prostheses. Understanding of how different shoes could alter certain gait-related characteristics of prostheses may aid decisions on footwear made by clinicians and prosthesis users. Clinical relevance Shoes can alter function of the prosthetic foot-shoe system in unexpected and sometimes undesirable ways, often causing similar behavior across setups despite differences in foot design, and prescribing clinicians should carefully consider these effects on prosthesis performance.

Biomechanical Reconstruction Using the Tacit Learning System: Intuitive Control of Prosthetic Hand Rotation.

Science.gov (United States)

Oyama, Shintaro; Shimoda, Shingo; Alnajjar, Fady S K; Iwatsuki, Katsuyuki; Hoshiyama, Minoru; Tanaka, Hirotaka; Hirata, Hitoshi

2016-01-01

Background: For mechanically reconstructing human biomechanical function, intuitive proportional control, and robustness to unexpected situations are required. Particularly, creating a functional hand prosthesis is a typical challenge in the reconstruction of lost biomechanical function. Nevertheless, currently available control algorithms are in the development phase. The most advanced algorithms for controlling multifunctional prosthesis are machine learning and pattern recognition of myoelectric signals. Despite the increase in computational speed, these methods cannot avoid the requirement of user consciousness and classified separation errors. "Tacit Learning System" is a simple but novel adaptive control strategy that can self-adapt its posture to environment changes. We introduced the strategy in the prosthesis rotation control to achieve compensatory reduction, as well as evaluated the system and its effects on the user. Methods: We conducted a non-randomized study involving eight prosthesis users to perform a bar relocation task with/without Tacit Learning System support. Hand piece and body motions were recorded continuously with goniometers, videos, and a motion-capture system. Findings: Reduction in the participants' upper extremity rotatory compensation motion was monitored during the relocation task in all participants. The estimated profile of total body energy consumption improved in five out of six participants. Interpretation: Our system rapidly accomplished nearly natural motion without unexpected errors. The Tacit Learning System not only adapts human motions but also enhances the human ability to adapt to the system quickly, while the system amplifies compensation generated by the residual limb. The concept can be extended to various situations for reconstructing lost functions that can be compensated.

Fuzzy linguistic hedges for the selection of manufacturing process for prosthetic sockets

Directory of Open Access Journals (Sweden)

Richa Pandey

2014-08-01

Full Text Available In this paper, a comparison is presented between two prime methods of producing prosthetic sockets by using the fuzzy linguistic hedges approach on the qualitative feedback of Indian prosthetic users. Recent trends indicate that the Indian manufacturers have tried to adopt the newer technologies like reverse engineering (RE approach to achieve the desired goals. However, the satisfaction of the user is of utmost importance for the unique and customized products for rehabilitation. In order to analyze the effectiveness of the manufacturing approaches, user case studies are taken, based on the linguistic feedbacks, and a comparative study is conducted. Thirteen users from four different manufacturing units are taken for study and sockets made by conventional as well as RE are experimented. Fuzzy membership functions are constructed using the linguistic hedges based on the user feedbacks. An analytical hierarchy process (AHP is applied to arrive at a decision to select the manufacturing process for user satisfaction and manufacturing excellence.

Efficiency of voluntary closing hand and hook prostheses

NARCIS (Netherlands)

Smit, G.; Plettenburg, D.H.

2010-01-01

The Delft Institute of Prosthetics and Orthotics has started a research program to develop an improved voluntary closing, body-powered hand prosthesis. Five commercially available voluntary closing terminal devices were mechanically tested: three hands [Hosmer APRL VC hand, Hosmer Soft VC Male hand,

The Persian version of satisfaction assessment module of Orthotics and Prosthetics Users' Survey.

Science.gov (United States)

Hadadi, Mohammad; Ghoseiri, Kamiar; Fardipour, Shima; Kashani, Reza Vahab; Asadi, Farnoosh; Asghari, Azizeh

2016-01-01

Orthotics and Prosthetics User's Survey (OPUS) was developed to measure patient satisfaction in Prosthetic and Orthotic (P&O) field. To translate the satisfaction assessment module of OPUS (OPUS-SM) into Persian language (Persian OPUS-SM) and investigate its psychometric properties. For cross-cultural adaptation of the OPUS-SM, the guideline suggested by the World Health Organization was recruited. A sample of 116 Persian-speaking people who received P&O devices and services, participated in this study. During the first session, participants filled out the Persian OPUS-SM and the Visual Analog Scale (VAS) regarding their satisfaction from delivered devices and services. Drawing from the above sample of 116 participants, 41 participants retook the Persian OPUS-SM 5-7 days after their first time. The results of the first and second administration sessions were analyzed to assess internal consistency, test-retest reliability, item-subscale correlation, minimal detectable change, floor and ceiling effects, criterion validity, and dimensionality of the Persian OPUS-SM. The Cronbach's alphas of the Persian OPUS-SM were 0.71 and 0.89 for device and service satisfaction subscales, respectively. The intraclass correlation coefficients were 0.76 and 0.90 for device and service satisfaction subscales, respectively. The SEM and MDC for device satisfaction were 6.21 and ±17.21, respectively. The SEM and MDC for service satisfaction were 2.25 and ±6.22, respectively. There was a strong correlation between VAS and satisfaction subscales of the Persian OPUS-SM. Dimensionality assessment revealed that Persian OPUS-SM is a unidimensional measure. The adapted and translated Persian OPUS-SM is a reliable and validated measure. Copyright © 2016 Elsevier Inc. All rights reserved.

Case study: survey of patient satisfaction with prosthesis quality and design among below-knee prosthetic leg socket users.

Science.gov (United States)

Mohd Hawari, Nurhanisah; Jawaid, Mohammad; Md Tahir, Paridah; Azmeer, Raja Ahmad

2017-11-01

The aim of this case study was to explore patient satisfaction with the quality of prosthetic leg sockets intended for persons with lower limb amputations. A qualitative study based on in-depth interviews, preceded by a questionnaire session, was carried out with patients from the Rehabilitation Center and Hospital in Malaysia. Twelve out-patient and in-patient amputees with lower limb amputations, specifically below-knee amputations, were chosen randomly. The analysis of patients' narratives aimed to identify the functional and esthetic characteristics of currently used prosthetic leg sockets and any problems related to them. The obtained results indicated that out of the 12 participants, 41.7% and 25% were satisfied and somewhat satisfied with their current prosthetic sockets. Durability and comfort were rated by the participants as the most important characteristics of prosthetic sockets, with 83.3%. As regards the esthetic appearance of the socket, 66.7% of the respondents considered that the most important feature was the material from which the socket was fabricated. Thus, we conclude that current satisfaction levels with the quality of prosthetic sockets among amputees in Malaysia are suitable, prosthesis being preferred by many amputees. The results can be used to direct future research on cosmesis and functionality of prosthetic socket design. Implications for Rehabilitation Case study will help participants to get cost effective prosthetic leg socket. Develop prosthetic leg socket comfortable as comparative to existing one. Help Malaysian government to make policy to develop local prosthetic leg socket at affordable price.

Use of Design Patterns According to Hand Dominance in a Mobile User Interface

Science.gov (United States)

Al-Samarraie, Hosam; Ahmad, Yusof

2016-01-01

User interface (UI) design patterns for mobile applications provide a solution to design problems and can improve the usage experience for users. However, there is a lack of research categorizing the uses of design patterns according to users' hand dominance in a learning-based mobile UI. We classified the main design patterns for mobile…

Development of inexpensive prosthetic feet for high-heeled shoes using simple shoe insole model

OpenAIRE

Margrit R. Meier, PhD; Kerice A. Tucker, BSc; Andrew H. Hansen, PhD

2014-01-01

The large majority of prosthetic feet are aimed at low-heeled shoes, with a few models allowing a heel height of up to 5 cm. However, a survey by the American Podiatric Medical Association indicates that most women wear heels over 5 cm; thus, current prosthetic feet limit most female prosthesis users in their choice. Some prosthetic foot components are heel-height adjustable; however, their plantar surface shapes do not change to match the insole shapes of the shoes with different heel height...

Development of a 3D-Printed Robotic Prosthetic Arm

Energy Technology Data Exchange (ETDEWEB)

Gomez Martinez, M.; Garcia-Miquel, A.; Vidal Martinez, N.

2016-07-01

Current prostheses are not affordable to the general public. 3D printing technology may allow low-cost production of such devices, making them more readily accessible to people in need. This contribution presents the set-up and the considerations that have to be taken into account to develop a functional artificial upper limb prototype. The robotic prosthetic arm reported herein was produced entirely using 3D printing technology to demonstrate its feasibility on a limited budget. The project was developed to integrate two different functional modes: a prosthetic application and a remote application. The prosthetic application is intended to emulate existing prosthetic devices using myoelectric sensors. The remote application is conceived as a tool for prevention, by providing the general public with a device that could carry out activities that entail a risk of severe physical injury. This is achieved using a hand-tracking system that allows the robotic arm to copy the user’s movements remotely and in real time. The outcome of the validation tests has been considerably successful for both applications and the total costs are on target. (Author)

Wide-Area Haptic Guidance: Taking the User by the Hand

OpenAIRE

Pérez Arias, Antonia; Hanebeck, Uwe D.

2010-01-01

In this paper, we present a novel use of haptic information in extended range telepresence, the wide-area haptic guidance. It consists of force and position signals applied to the user's hand in order to improve safety, accuracy, and speed in some telepresent tasks. Wide-area haptic guidance assists the user in reaching a desired position in a remote environment of arbitrary size without degrading the feeling of presence. Several methods for haptic guidance are analyzed. With active haptic gu...

Two hands are better than one: a new assessment method and a new interpretation of the non-visual illusion of self-touch.

Science.gov (United States)

White, Rebekah C; Aimola Davies, Anne M; Davies, Martin

2011-09-01

A simple experimental paradigm creates the powerful illusion that one is touching one's own hand even when the two hands are separated by 15 cm. The participant uses her right hand to administer stimulation to a prosthetic hand while the Examiner provides identical stimulation to the participant's receptive left hand. Change in felt position of the receptive hand toward the prosthetic hand has previously led to the interpretation that the participant experiences self-touch at the location of the prosthetic hand, and experiences a sense of ownership of the prosthetic hand. Our results argue against this interpretation. We assessed change in felt position of the participant's receptive hand but we also assessed change in felt position of the participant's administering hand. Change in felt position of the administering hand was significantly greater than change in felt position of the receptive hand. Implications for theories of ownership are discussed. Copyright © 2011 Elsevier Inc. All rights reserved.

Experiences in the creation of an electromyography database to help hand amputated persons.

Science.gov (United States)

Atzori, Manfredo; Gijsberts, Arjan; Heynen, Simone; Hager, Anne-Gabrielle Mittaz; Castellimi, Claudio; Caputo, Barbara; Müller, Henning

2012-01-01

Currently, trans-radial amputees can only perform a few simple movements with prosthetic hands. This is mainly due to low control capabilities and the long training time that is required to learn controlling them with surface electromyography (sEMG). This is in contrast with recent advances in mechatronics, thanks to which mechanical hands have multiple degrees of freedom and in some cases force control. To help improve the situation, we are building the NinaPro (Non-Invasive Adaptive Prosthetics) database, a database of about 50 hand and wrist movements recorded from several healthy and currently very few amputated persons that will help the community to test and improve sEMG-based natural control systems for prosthetic hands. In this paper we describe the experimental experiences and practical aspects related to the data acquisition.

Deep learning with convolutional neural networks: a resource for the control of robotic prosthetic hands via electromyography

Directory of Open Access Journals (Sweden)

Manfredo Atzori

2016-09-01

Full Text Available Motivation: Natural control methods based on surface electromyography and pattern recognition are promising for hand prosthetics. However, the control robustness offered by scientific research is still not sufficient for many real life applications and commercial prostheses are in the best case capable to offer natural control for only a few movements. Objective: In recent years deep learning revolutionized several fields of machine learning, including computer vision and speech recognition. Our objective is to test its capabilities for the natural control of robotic hands via surface electromyography by providing a baseline on a large number of intact and amputated subjects. Methods: We tested convolutional networks for the classification of an average of 50 hand movements in 67 intact subjects and 11 hand amputated subjects. The simple architecture of the neural network allowed to make several tests in order to evaluate the effect of pre-processing, layer architecture, data augmentation and optimization. The classification results are compared with a set of classical classification methods applied on the same datasets.Results: The classification accuracy obtained with convolutional neural networks using the proposed architecture is higher than the average results obtained with the classical classification methods but lower than the results obtained with the best reference methods in our tests. Significance: The results show that convolutional neural networks with a very simple architecture can produce accuracy comparable to the average classical classification methods. They show that several factors (including pre-processing, the architecture of the net and the optimization parameters can be fundamental for the analysis of surface electromyography data. Finally, the results suggest that deeper and more complex networks may increase dexterous control robustness, thus contributing to bridge the gap between the market and scientific research

Comparative study of state-of-the-art myoelectric controllers for multigrasp prosthetic hands.

Science.gov (United States)

Segil, Jacob L; Controzzi, Marco; Weir, Richard F ff; Cipriani, Christian

2014-01-01

A myoelectric controller should provide an intuitive and effective human-machine interface that deciphers user intent in real-time and is robust enough to operate in daily life. Many myoelectric control architectures have been developed, including pattern recognition systems, finite state machines, and more recently, postural control schemes. Here, we present a comparative study of two types of finite state machines and a postural control scheme using both virtual and physical assessment procedures with seven nondisabled subjects. The Southampton Hand Assessment Procedure (SHAP) was used in order to compare the effectiveness of the controllers during activities of daily living using a multigrasp artificial hand. Also, a virtual hand posture matching task was used to compare the controllers when reproducing six target postures. The performance when using the postural control scheme was significantly better (p state machines during the physical assessment when comparing within-subject averages using the SHAP percent difference metric. The virtual assessment results described significantly greater completion rates (97% and 99%) for the finite state machines, but the movement time tended to be faster (2.7 s) for the postural control scheme. Our results substantiate that postural control schemes rival other state-of-the-art myoelectric controllers.

Analysis of relative displacement between the HX wearable robotic exoskeleton and the user's hand.

Science.gov (United States)

Cempini, Marco; Marzegan, Alberto; Rabuffetti, Marco; Cortese, Mario; Vitiello, Nicola; Ferrarin, Maurizio

2014-10-18

Advances in technology are allowing for the production of several viable wearable robotic devices to assist with activities of daily living and with rehabilitation. One of the most pressing limitations to user satisfaction is the lack of consistency in motion between the user and the robotic device. The displacement between the robot and the body segment may not correspond because of differences in skin and tissue compliance, mechanical backlash, and/or incorrect fit. This report presents the results of an analysis of relative displacement between the user's hand and a wearable exoskeleton, the HX. HX has been designed to maximize comfort, wearability and user safety, exploiting chains with multiple degrees-of-freedom with a modular architecture. These appealing features may introduce several uncertainties in the kinematic performances, especially when considering the anthropometry, morphology and degree of mobility of the human hand. The small relative displacements between the hand and the exoskeleton were measured with a video-based motion capture system, while the user executed several different grips in different exoskeleton modes. The analysis furnished quantitative results about the device performance, differentiated among device modules and test conditions. In general, the global relative displacement for the distal part of the device was in the range 0.5-1.5 mm, while within 3 mm (worse but still acceptable) for displacements nearest to the hand dorsum. Conclusions over the HX design principles have been drawn, as well as guidelines for future developments.

Grasp specific and user friendly interface design for myoelectric hand prostheses.

Science.gov (United States)

Mohammadi, Alireza; Lavranos, Jim; Howe, Rob; Choong, Peter; Oetomo, Denny

2017-07-01

This paper presents the design and characterisation of a hand prosthesis and its user interface, focusing on performing the most commonly used grasps in activities of daily living (ADLs). Since the operation of a multi-articulated powered hand prosthesis is difficult to learn and master, there is a significant rate of abandonment by amputees in preference for simpler devices. In choosing so, amputees chose to live with fewer features in their prosthesis that would more reliably perform the basic operations. In this paper, we look simultaneously at a hand prosthesis design method that aims for a small number of grasps, a low complexity user interface and an alternative method to the current use of EMG as a preshape selection method through the use of a simple button; to enable amputees to get to and execute the intended hand movements intuitively, quickly and reliably. An experiment is reported at the end of the paper comparing the speed and accuracy with which able-bodied naive subjects are able to select the intended preshapes through the use of a simplified EMG method and a simple button. It is shown that the button was significantly superior in the speed of successful task completion and marginally superior in accuracy (success of first attempt).

User evaluation of patient counselling, combining nurse consultation and eHealth in hand eczema.

Science.gov (United States)

Mollerup, Annette; Harboe, Gitte; Johansen, Jeanne D

2016-04-01

This study reports the findings from a user evaluation of a counselling programme for hand eczema patients in which face-to-face encounters were supplemented with user access to a new website. Patients treated for hand eczema in two different settings were included consecutively. Website utilization was examined by use of the transaction log. Comparisons were made between participants who used the website and those who did not. The patients' perspectives were explored by the use of interviews. Among potential website users (n = 140), 88 patients (63%) had an average of 5.1 site visits. At follow-up, the website users had improved more in quality of life (p = 0.014), current burden of disease (p = 0.053), and itching (p = 0.042). The website users reported more changes in habits than did the non-website users (p = 0.024). No differences in clinical severity of hand eczema were found. The interviewees were generally satisfied with the counselling and the website. The strict log-on procedures were considered to be an obstacle to using the site. The consecutive inclusion of participants was considered to be a barrier to engagement in the dialogue forum. The website users benefited from the website, although this was not substantiated by clinical measurements. The trial design partly hampered website utilization. An initial feasibility study could have been warranted. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Electromyogram synergy control of a dexterous artificial hand to unscrew and screw objects.

Science.gov (United States)

Kent, Benjamin A; Karnati, Nareen; Engeberg, Erik D

2014-03-21

Due to their limited dexterity, it is currently not possible to use a commercially available prosthetic hand to unscrew or screw objects without using elbow and shoulder movements. For these tasks, prosthetic hands function like a wrench, which is unnatural and limits their use in tight working environments. Results from timed rotational tasks with human subjects demonstrate the clinical need for increased dexterity of prosthetic hands, and a clinically viable solution to this problem is presented for an anthropomorphic artificial hand. Initially, a human hand motion analysis was performed during a rotational task. From these data, human hand synergies were derived and mapped to an anthropomorphic artificial hand. The synergy for the artificial hand is controlled using conventional dual site electromyogram (EMG) signals. These EMG signals were mapped to the developed synergy to control four joints of the dexterous artificial hand simultaneously.Five limb absent and ten able-bodied test subjects participated in a comparison study to complete a timed rotational task as quickly as possible with their natural hands (except for one subject with a bilateral hand absence), eight commercially available prosthetic hands, and the proposed synergy controller. Each test subject used two to four different artificial hands. With the able-bodied subjects, the developed synergy controller reduced task completion time by 177% on average. The limb absent subjects completed the task faster on average than with their own prostheses by 46%. There was a statistically significant improvement in task completion time with the synergy controller for three of the four limb absent participants with integrated prostheses, and was not statistically different for the fourth. The proposed synergy controller reduced average task completion time compared to commercially available prostheses. Additionally, the synergy controller is able to function in a small workspace and requires less physical

Development of novel 3D-printed robotic prosthetic for transradial amputees.

Science.gov (United States)

Gretsch, Kendall F; Lather, Henry D; Peddada, Kranti V; Deeken, Corey R; Wall, Lindley B; Goldfarb, Charles A

2016-06-01

Upper extremity myoelectric prostheses are expensive. The Robohand demonstrated that three-dimensional printing reduces the cost of a prosthetic extremity. The goal of this project was to develop a novel, inexpensive three-dimensional printed prosthesis to address limitations of the Robohand. The prosthesis was designed for patients with transradial limb amputation. It is shoulder-controlled and externally powered with an anthropomorphic terminal device. The user can open and close all five fingers, and move the thumb independently. The estimated cost is US$300. After testing on a patient with a traumatic transradial amputation, several advantages were noted. The independent thumb movement facilitated object grasp, the device weighed less than most externally powered prostheses, and the size was easily scalable. Limitations of the new prosthetic include low grip strength and decreased durability compared to passive prosthetics. Most children with a transradial congenital or traumatic amputation do not use a prosthetic. A three-dimensional printed shoulder-controlled robotic prosthesis provides a cost effective, easily sized and highly functional option which has been previously unavailable. © The International Society for Prosthetics and Orthotics 2015.

Fiscal 2000 project of inviting proposals for international joint research - invitation for international proposal (Novel No.3). Achievement report on research and development of highly adaptive prosthetic upper limbs; 2000 nendo kokusai kyodo kenkyu teian kobo jigyo - kokusai teian kobo (shinki No.3). Tekiogata joshi hosogu no kenkyu kaihatsu seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

Efforts are exerted to develop prosthetic upper limbs easy to operate and high in reliability. Development activities are conducted in the three fields of (1) the study of a sensor feedback type power-driven prosthetic hands, (2) development of a power assist for upper limbs, and (3) the goal and self-evaluation. In field (1), pending problems are taken up, evaluation (Jet Propulsion Laboratory of National Aeronautics and Space Administration, U.S.) is made, evaluation report is studied, new objects of development are named, and power-driven prosthetic hands are manufactured. As the result, small and light prosthetic hands are built, capable of performing delicate acts. They want more grasping power, however, and want improvement. In field (2), the development goal is studied, and efforts are made to develop a power assist mechanism. As the result, a basic mechanism that can bend and extend each of the fingers is now complete although some problems remain to be solved for the users to operate them conveniently in their daily life. The technologies mentioned in this report may be applied also to massaging instruments, power input devices for robotic manipulators, and a force feedback aided situation recognition system utilizing the power transmission mechanism. (NEDO)

A comparison of computerized adaptive testing and fixed-length short forms for the Prosthetic Limb Users Survey of Mobility (PLUS-MTM).

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Amtmann, Dagmar; Bamer, Alyssa M; Kim, Jiseon; Bocell, Fraser; Chung, Hyewon; Park, Ryoungsun; Salem, Rana; Hafner, Brian J

2017-09-01

New health status instruments can be administered by computerized adaptive test or short forms. The Prosthetic Limb Users Survey of Mobility (PLUS-M TM ) is a self-report measure of mobility for prosthesis users with lower limb loss. This study used the PLUS-M to examine advantages and disadvantages of computerized adaptive test and short forms. To compare scores obtained from computerized adaptive test to scores obtained from fixed-length short forms (7-item and 12-item) in order to provide guidance to researchers and clinicians on how to select the best form of administration for different uses. Cross-sectional, observational study. Individuals with lower limb loss completed the PLUS-M by computerized adaptive test and short forms. Administration time, correlations between the scores, and standard errors were compared. Scores and standard errors from the computerized adaptive test, 7-item short form, and 12-item short form were highly correlated and all forms of administration were efficient. Computerized adaptive test required less time to administer than either paper or electronic short forms; however, time savings were minimal compared to the 7-item short form. Results indicate that the PLUS-M computerized adaptive test is most efficient, and differences in scores between administration methods are minimal. The main advantage of the computerized adaptive test was more reliable scores at higher levels of mobility compared to short forms. Clinical relevance Health-related item banks, like the Prosthetic Limb Users Survey of Mobility (PLUS-M TM ), can be administered by computerized adaptive testing (CAT) or as fixed-length short forms (SFs). Results of this study will help clinicians and researchers decide whether they should invest in a CAT administration system or whether SFs are more appropriate.

Myoelectric intuitive control and transcutaneous electrical stimulation of the forearm for vibrotactile sensation feedback applied to a 3D printed prosthetic hand.

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Germany, Enrique I; Pino, Esteban J; Aqueveque, Pablo E

2016-08-01

This paper presents the development of a myoelectric prosthetic hand based on a 3D printed model. A myoelectric control strategy based on artificial neural networks is implemented on a microcontroller for online position estimation. Position estimation performance achieves a correlation index of 0.78. Also a study involving transcutaneous electrical stimulation was performed to provide tactile feedback. A series of stimulations with controlled parameters were tested on five able-body subjects. A single channel stimulator was used, positioning the electrodes 8 cm on the wrist over the ulnar and median nerve. Controlling stimulation parameters such as intensity, frequency and pulse width, the subjects were capable of distinguishing different sensations over the palm of the hand. Three main sensations where achieved: tickling, pressure and pain. Tickling and pressure were discretized into low, moderate and high according to the magnitude of the feeling. The parameters at which each sensation was obtained are further discussed in this paper.

One-Handed Thumb Use on Smart Phones by Semi-literate and Illiterate Users in India

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Katre, Dinesh

There is a tremendous potential for developing mobile-based productivity tools and occupation specific applications for the semi-literate and illiterate users in India. One-handed thumb use on the touchscreen of smart phone or touch phone is considered as an effective alternative than the use of stylus or index finger, to free the other hand for supporting the occupational activity. In this context, usability research and experimental tests are conducted to understand the role of fine motor control, usability of thumb as the interaction apparatus and the ergonomic needs of users. The paper also touches upon cultural, racial and anthropometric aspects, which need due consideration while designing the mobile interface. Design recommendations are evolved to enhance the effectiveness of one-handed thumb use on smart phone, especially for the benefit of semi-literate and illiterate users.

An Alternative Myoelectric Pattern Recognition Approach for the Control of Hand Prostheses: A Case Study of Use in Daily Life by a Dysmelia Subject

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Ahlberg, Johan; Lendaro, Eva; Hermansson, Liselotte; Håkansson, Bo; Ortiz-Catalan, Max

2018-01-01

The functionality of upper limb prostheses can be improved by intuitive control strategies that use bioelectric signals measured at the stump level. One such strategy is the decoding of motor volition via myoelectric pattern recognition (MPR), which has shown promising results in controlled environments and more recently in clinical practice. Moreover, not much has been reported about daily life implementation and real-time accuracy of these decoding algorithms. This paper introduces an alternative approach in which MPR allows intuitive control of four different grips and open/close in a multifunctional prosthetic hand. We conducted a clinical proof-of-concept in activities of daily life by constructing a self-contained, MPR-controlled, transradial prosthetic system provided with a novel user interface meant to log errors during real-time operation. The system was used for five days by a unilateral dysmelia subject whose hand had never developed, and who nevertheless learned to generate patterns of myoelectric activity, reported as intuitive, for multi-functional prosthetic control. The subject was instructed to manually log errors when they occurred via the user interface mounted on the prosthesis. This allowed the collection of information about prosthesis usage and real-time classification accuracy. The assessment of capacity for myoelectric control test was used to compare the proposed approach to the conventional prosthetic control approach, direct control. Regarding the MPR approach, the subject reported a more intuitive control when selecting the different grips, but also a higher uncertainty during proportional continuous movements. This paper represents an alternative to the conventional use of MPR, and this alternative may be particularly suitable for a certain type of amputee patients. Moreover, it represents a further validation of MPR with dysmelia cases. PMID:29637030

Advanced upper limb prosthetic devices: implications for upper limb prosthetic rehabilitation.

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Resnik, Linda; Meucci, Marissa R; Lieberman-Klinger, Shana; Fantini, Christopher; Kelty, Debra L; Disla, Roxanne; Sasson, Nicole

2012-04-01

The number of catastrophic injuries caused by improvised explosive devices in the Afghanistan and Iraq Wars has increased public, legislative, and research attention to upper limb amputation. The Department of Veterans Affairs (VA) has partnered with the Defense Advanced Research Projects Agency and DEKA Integrated Solutions to optimize the function of an advanced prosthetic arm system that will enable greater independence and function. In this special communication, we examine current practices in prosthetic rehabilitation including trends in adoption and use of prosthetic devices, financial considerations, and the role of rehabilitation team members in light of our experiences with a prototype advanced upper limb prosthesis during a VA study to optimize the device. We discuss key challenges in the adoption of advanced prosthetic technology and make recommendations for service provision and use of advanced upper limb prosthetics. Rates of prosthetic rejection are high among upper limb amputees. However, these rates may be reduced with sufficient training by a highly specialized, multidisciplinary team of clinicians, and a focus on patient education and empowerment throughout the rehabilitation process. There are significant challenges emerging that are unique to implementing the use of advanced upper limb prosthetic technology, and a lack of evidence to establish clinical guidelines regarding prosthetic prescription and treatment. Finally, we make recommendations for future research to aid in the identification of best practices and development of policy decisions regarding insurance coverage of prosthetic rehabilitation. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

A synergy-driven approach to a myoelectric hand.

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Godfrey, S B; Ajoudani, A; Catalano, M; Grioli, G; Bicchi, A

2013-06-01

In this paper, we present the Pisa/IIT SoftHand with myoelectric control as a synergy-driven approach for a prosthetic hand. Commercially available myoelectric hands are more expensive, heavier, and less robust than their body-powered counterparts; however, they can offer greater freedom of motion and a more aesthetically pleasing appearance. The Pisa/IIT SoftHand is built on the motor control principle of synergies through which the immense complexity of the hand is simplified into distinct motor patterns. As the SoftHand grasps, it follows a synergistic path with built-in flexibility to allow grasping of a wide variety of objects with a single motor. Here we test, as a proof-of-concept, 4 myoelectric controllers: a standard controller in which the EMG signal is used only as a position reference, an impedance controller that determines both position and stiffness references from the EMG input, a standard controller with vibrotactile force feedback, and finally a combined vibrotactile-impedance (VI) controller. Four healthy subjects tested the control algorithms by grasping various objects. All controllers were sufficient for basic grasping, however the impedance and vibrotactile controllers reduced the physical and cognitive load on the user, while the combined VI mode was the easiest to use of the four. While these results need to be validated with amputees, they suggest a low-cost, robust hand employing hardware-based synergies is a viable alternative to traditional myoelectric prostheses.

Development of inexpensive prosthetic feet for high-heeled shoes using simple shoe insole model.

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Meier, Margrit R; Tucker, Kerice A; Hansen, Andrew H

2014-01-01

The large majority of prosthetic feet are aimed at low-heeled shoes, with a few models allowing a heel height of up to 5 cm. However, a survey by the American Podiatric Medical Association indicates that most women wear heels over 5 cm; thus, current prosthetic feet limit most female prosthesis users in their choice. Some prosthetic foot components are heel-height adjustable; however, their plantar surface shapes do not change to match the insole shapes of the shoes with different heel heights. The aims of the study were therefore (1) to develop a model that allows prediction of insole shape for various heel height shoes in combination with different shoe sizes and (2) to develop and field-test low-cost prototypes of prosthetic feet whose insole shapes were based on the new model. An equation was developed to calculate insole shapes independent of shoe size. Field testing of prototype prosthetic feet fabricated based on the equation was successful and demonstrated the utility of the equation.

Constraint Study for a Hand Exoskeleton: Human Hand Kinematics and Dynamics

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Fai Chen Chen

2013-01-01

Full Text Available In the last few years, the number of projects studying the human hand from the robotic point of view has increased rapidly, due to the growing interest in academic and industrial applications. Nevertheless, the complexity of the human hand given its large number of degrees of freedom (DoF within a significantly reduced space requires an exhaustive analysis, before proposing any applications. The aim of this paper is to provide a complete summary of the kinematic and dynamic characteristics of the human hand as a preliminary step towards the development of hand devices such as prosthetic/robotic hands and exoskeletons imitating the human hand shape and functionality. A collection of data and constraints relevant to hand movements is presented, and the direct and inverse kinematics are solved for all the fingers as well as the dynamics; anthropometric data and dynamics equations allow performing simulations to understand the behavior of the finger.

From satisfaction to expectation: the patient's perspective in lower limb prosthetic care.

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Van der Linde, Harmen; Hofstad, Cheriel J; Geertzen, Jan H B; Postema, Klaas; Van Limbeek, Jacques

2007-07-15

To obtain information about the wishes and experiences of patients with a lower limb amputation with regard to prosthetic prescription and their exchange of information with the healthcare providers. Cross-sectional questionnaire. Outpatient clinic of a Rehabilitation Centre. A random sample of patients with a lower limb amputation (n = 81). In analogy with the QUOTE questionnaire a focus group technique was used. Prosthetic users formulated 24 specific items, which were of importance according to them. The items were divided into 4 categories: (i) service demand, (ii) prosthetic prescription, (iii) information, (iv) insurance aspects. The questionnaire consisted of two sets (A and B) of 24 items rating importance of items and experience in everyday practice. To identify different dimensions within the 24 items, a factor analysis in SPSS was performed for lists A and B followed by a varimax rotation. Impact factors were calculated by multiplying the mean score of importance on an item with the percentage of patients that experienced this item as negative. A total of 113 questionnaires were sent by e-mail with a response of 73%. The outcomes of the questionnaires resulted in 2 sets of information: One concerning the importance of several items in the process of prosthetic prescription, the other the experience of the prosthetic user about those items. By multiplying the scores on importance by the percentage of negative experience per item (impact score) points of improvement for clinical practice were formulated. A discrepancy between the needs of patients and what they experience in their contacts with clinical professionals as the most important dimension was noticed. A questionnaire with specific items for a homogeneous target group is a good method to formulate points of improvement for clinical practice in healthcare.

Fusion of hard and soft control strategies for the robotic hand

CERN Document Server

Chen, Cheng-Hung

2018-01-01

Long considered the stuff of science fiction, a prosthetic hand capable of fully replicating all of that appendage's various functions is closer to becoming reality than ever before. This book provides a comprehensive report on exciting recent developments in hybrid control techniques—one of the most crucial hurdles to be overcome in creating smart prosthetic hands. Coauthored by two of the world's foremost pioneering experts in the field, Fusion of Hard and Soft Control Strategies for the Robotic Hand treats robotic hands for multiple applications. It begins with an overview of advances in main control techniques that have been made over the past decade before addressing the military context for affordable robotic hand technology with tactile and/or proprioceptive feedback for hand amputees. Kinematics, homogene us transformations, inverse and differential kinematics, trajectory planning, and dynamic models of two-link thumb and three-link index finger are discussed in detail. The remainder of the book is...

Psychometric evaluation of self-report outcome measures for prosthetic applications.

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Hafner, Brian J; Morgan, Sara J; Askew, Robert L; Salem, Rana

2016-01-01

Documentation of clinical outcomes is increasingly expected in delivery of prosthetic services and devices. However, many outcome measures suitable for use in clinical care and research have not been psychometrically tested with prosthesis users. The aim of this study was to determine test-retest reliability, mode-of-administration (MoA) equivalence, standard error of measurement (SEM), and minimal detectable change (MDC) of standardized, self-report instruments that assess constructs of importance to people with lower limb loss. Prosthesis users (n = 201) were randomly assigned to groups based on MoA (i.e., paper, electronic, or mixed-mode). Participants completed two surveys 2 to 3 d apart. Instruments included the Prosthetic Limb Users Survey of Mobility, Prosthesis Evaluation Questionnaire-Mobility Subscale, Activities-Specific Balance Confidence Scale, Quality of Life in Neurological Conditions-Applied Cognition/General Concerns, Patient-Reported Outcomes Measurement Information System Profile, and Socket Comfort Score. Intraclass correlation coefficients indicated all instruments are appropriate for group-level comparisons and select instruments are suitable for individual-level applications. Several instruments showed evidence of possible floor and ceiling effects. All were equivalent across MoAs. SEM and MDC were quantified to facilitate interpretation of outcomes and change scores. These results can enhance clinicians' and researchers' ability to select, apply, and interpret scores from instruments administered to prosthesis users.

A survey of prosthetic eye wearers to investigate mucoid discharge

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Pine K

2012-05-01

Full Text Available Keith Pine1, Brian Sloan2, Joanna Stewart3, Robert J Jacobs11Department of Optometry and Vision Science, 2Department of Ophthalmology, New Zealand National Eye Centre, 3Section of Epidemiology and Biostatistics, School of Population Health, University of Auckland, Auckland, New ZealandBackground: This study aimed to better understand the causes and treatments of mucoid discharge associated with prosthetic eye wear by reviewing the literature and surveying anophthalmic patients.Methods: An anonymous questionnaire was completed by 429 prosthetic eye wearers who used visual analog scales to self-measure their discharge experience for four discharge characteristics: frequency, color, volume, and viscosity. These characteristics were analyzed with age, ethnicity, years wearing a prosthesis, eye loss cause, removal and cleaning regimes, hand-washing behavior, age of current prosthesis, and professional repolishing regimes as explanatory variables. Eighteen ocularists’ Web sites containing comments on the cause and treatment of discharge were surveyed.Results: Associations were found between discharge frequency and cleaning regimes with more frequent cleaning accompanying more frequent discharge. Color was associated with years of wearing and age, with more years of wearing and older people having less colored discharge. Volume was associated with cleaning regimes with more frequent cleaners having more volume. Viscosity was associated with cleaning regimes and years of wearing with more frequent cleaning and shorter wearing time accompanying more viscous discharge. No associations were found between discharge characteristics and ethnicity, eye loss cause, hand washing, age of current prosthesis, or repolishing regimes. Forty-seven percent of ocularists’ Web sites advised that discharge was caused by surface deposits on the prosthesis, 29% by excessive handling of the prosthesis, and 24% by other causes.Conclusions: A standardized treatment

An Evaluation of Dental Prosthetic Status and Prosthetic Needs ...

African Journals Online (AJOL)

present cross‑sectional study aimed to evaluate the dental prosthetic status and prosthetic needs among eunuchs .... who consented to become part of the study guided us to the .... to the reason that our study population comprised of adults with low SES. ... Arora M, Schwarz E, Sivaneswaran S, Banks E. Cigarette smoking.

Ergonomic workplace assessment in orthotic and prosthetic workshops.

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Salmani Nodooshan, H; Koohi Booshehri, S; Daneshmandi, H; Choobineh, A R

2016-10-17

In Iranian orthotic and prosthetic workshops, the majority of activities are carried out by manpower and the tasks are labor-intensive. In these workshops, ergonomic aspects of working conditions are seldom considered. This study was conducted in orthotic and prosthetic workshops with the objectives of determination of prevalence rate of MSDs among employees and assessment of ergonomics working conditions. In this cross-sectional study, all employees (n = 42; 29 males and 13 females) in 11 active orthotic and prosthetic production centers of Shiraz city participated. Data were collected using Nordic Musculoskeletal disorders Questionnaire (NMQ) and observational technique by an ergonomics checklist for assessment of working conditions. The means (SD) of age and job tenure (years) in the study individuals were 37.26 (10.21) and 12.8 (9.39), respectively. The most prevalent MSD symptoms in the past 12 months were reported in the lower back (42.9%), shoulders (40.5%) and knees (40.5%). Working conditions assessment showed that the main ergonomic problems in the workshops studied originated from awkward working posture, improper workstation design, poorly designed hand tools and incorrect manual material handling. Any interventional program for working conditions improvement should, therefore, focus on these areas.

The SmartHand transradial prosthesis

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Carrozza Maria Chiara

2011-05-01

Full Text Available Abstract Background Prosthetic components and control interfaces for upper limb amputees have barely changed in the past 40 years. Many transradial prostheses have been developed in the past, nonetheless most of them would be inappropriate if/when a large bandwidth human-machine interface for control and perception would be available, due to either their limited (or inexistent sensorization or limited dexterity. SmartHand tackles this issue as is meant to be clinically experimented in amputees employing different neuro-interfaces, in order to investigate their effectiveness. This paper presents the design and on bench evaluation of the SmartHand. Methods SmartHand design was bio-inspired in terms of its physical appearance, kinematics, sensorization, and its multilevel control system. Underactuated fingers and differential mechanisms were designed and exploited in order to fit all mechatronic components in the size and weight of a natural human hand. Its sensory system was designed with the aim of delivering significant afferent information to the user through adequate interfaces. Results SmartHand is a five fingered self-contained robotic hand, with 16 degrees of freedom, actuated by 4 motors. It integrates a bio-inspired sensory system composed of 40 proprioceptive and exteroceptive sensors and a customized embedded controller both employed for implementing automatic grasp control and for potentially delivering sensory feedback to the amputee. It is able to perform everyday grasps, count and independently point the index. The weight (530 g and speed (closing time: 1.5 seconds are comparable to actual commercial prostheses. It is able to lift a 10 kg suitcase; slippage tests showed that within particular friction and geometric conditions the hand is able to stably grasp up to 3.6 kg cylindrical objects. Conclusions Due to its unique embedded features and human-size, the SmartHand holds the promise to be experimentally fitted on transradial

NONLINEAR FORCE PROFILE USED TO INCREASE THE PERFORMANCE OF A HAPTIC USER INTERFACE FOR TELEOPERATING A ROBOTIC HAND

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Anthony L. Crawford

2012-07-01

MODIFIED PAPER TITLE AND ABSTRACT DUE TO SLIGHTLY MODIFIED SCOPE: TITLE: Nonlinear Force Profile Used to Increase the Performance of a Haptic User Interface for Teleoperating a Robotic Hand Natural movements and force feedback are important elements in using teleoperated equipment if complex and speedy manipulation tasks are to be accomplished in hazardous environments, such as hot cells, glove boxes, decommissioning, explosives disarmament, and space. The research associated with this paper hypothesizes that a user interface and complementary radiation compatible robotic hand that integrates the human hand’s anthropometric properties, speed capability, nonlinear strength profile, reduction of active degrees of freedom during the transition from manipulation to grasping, and just noticeable difference force sensation characteristics will enhance a user’s teleoperation performance. The main contribution of this research is in that a system that concisely integrates all these factors has yet to be developed and furthermore has yet to be applied to a hazardous environment as those referenced above. In fact, the most prominent slave manipulator teleoperation technology in use today is based on a design patented in 1945 (Patent 2632574) [1]. The robotic hand/user interface systems of similar function as the one being developed in this research limit their design input requirements in the best case to only complementing the hand’s anthropometric properties, speed capability, and linearly scaled force application relationship (e.g. robotic force is a constant, 4 times that of the user). In this paper a nonlinear relationship between the force experienced between the user interface and the robotic hand was devised based on property differences of manipulation and grasping activities as they pertain to the human hand. The results show that such a relationship when subjected to a manipulation task and grasping task produces increased performance compared to the

A two DoF finger for a biomechatronic artificial hand.

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Carrozza, M C; Massa, B; Dario, P; Zecca, M; Micera, S; Pastacaldi, P

2002-01-01

Current prosthetic hands are basically simple grippers with one or two degrees of freedom, which barely restore the capability of the thumb-index pinch. Although most amputees consider this performance as acceptable for usual tasks, there is ample room for improvement by exploiting recent progresses in mechatronics design and technology. We are developing a novel prosthetic hand featured by multiple degrees of freedom, tactile sensing capabilities, and distributed control. Our main goal is to pursue an integrated design approach in order to fulfill critical requirements such as cosmetics, controllability, low weight, low energy consumption and noiselessness. This approach can be synthesized by the definition "biomechatronic design", which means developing mechatronic systems inspired by living beings and able to work harmoniously with them. This paper describes the first implementation of one single finger of a future biomechatronic hand. The finger has a modular design, which allows to obtain hands with different degrees of freedom and grasping capabilities. Current developments include the implementation of a hand comprising three fingers (opposing thumb, index and middle) and an embedded controller.

Evaluation of 3D printed anatomically scalable transfemoral prosthetic knee.

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Ramakrishnan, Tyagi; Schlafly, Millicent; Reed, Kyle B

2017-07-01

This case study compares a transfemoral amputee's gait while using the existing Ossur Total Knee 2000 and our novel 3D printed anatomically scalable transfemoral prosthetic knee. The anatomically scalable transfemoral prosthetic knee is 3D printed out of a carbon-fiber and nylon composite that has a gear-mesh coupling with a hard-stop weight-actuated locking mechanism aided by a cross-linked four-bar spring mechanism. This design can be scaled using anatomical dimensions of a human femur and tibia to have a unique fit for each user. The transfemoral amputee who was tested is high functioning and walked on the Computer Assisted Rehabilitation Environment (CAREN) at a self-selected pace. The motion capture and force data that was collected showed that there were distinct differences in the gait dynamics. The data was used to perform the Combined Gait Asymmetry Metric (CGAM), where the scores revealed that the overall asymmetry of the gait on the Ossur Total Knee was more asymmetric than the anatomically scalable transfemoral prosthetic knee. The anatomically scalable transfemoral prosthetic knee had higher peak knee flexion that caused a large step time asymmetry. This made walking on the anatomically scalable transfemoral prosthetic knee more strenuous due to the compensatory movements in adapting to the different dynamics. This can be overcome by tuning the cross-linked spring mechanism to emulate the dynamics of the subject better. The subject stated that the knee would be good for daily use and has the potential to be adapted as a running knee.

Deep Learning with Convolutional Neural Networks Applied to Electromyography Data: A Resource for the Classification of Movements for Prosthetic Hands.

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Atzori, Manfredo; Cognolato, Matteo; Müller, Henning

2016-01-01

Natural control methods based on surface electromyography (sEMG) and pattern recognition are promising for hand prosthetics. However, the control robustness offered by scientific research is still not sufficient for many real life applications, and commercial prostheses are capable of offering natural control for only a few movements. In recent years deep learning revolutionized several fields of machine learning, including computer vision and speech recognition. Our objective is to test its methods for natural control of robotic hands via sEMG using a large number of intact subjects and amputees. We tested convolutional networks for the classification of an average of 50 hand movements in 67 intact subjects and 11 transradial amputees. The simple architecture of the neural network allowed to make several tests in order to evaluate the effect of pre-processing, layer architecture, data augmentation and optimization. The classification results are compared with a set of classical classification methods applied on the same datasets. The classification accuracy obtained with convolutional neural networks using the proposed architecture is higher than the average results obtained with the classical classification methods, but lower than the results obtained with the best reference methods in our tests. The results show that convolutional neural networks with a very simple architecture can produce accurate results comparable to the average classical classification methods. They show that several factors (including pre-processing, the architecture of the net and the optimization parameters) can be fundamental for the analysis of sEMG data. Larger networks can achieve higher accuracy on computer vision and object recognition tasks. This fact suggests that it may be interesting to evaluate if larger networks can increase sEMG classification accuracy too.

Deep Learning with Convolutional Neural Networks Applied to Electromyography Data: A Resource for the Classification of Movements for Prosthetic Hands

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Atzori, Manfredo; Cognolato, Matteo; Müller, Henning

2016-01-01

Natural control methods based on surface electromyography (sEMG) and pattern recognition are promising for hand prosthetics. However, the control robustness offered by scientific research is still not sufficient for many real life applications, and commercial prostheses are capable of offering natural control for only a few movements. In recent years deep learning revolutionized several fields of machine learning, including computer vision and speech recognition. Our objective is to test its methods for natural control of robotic hands via sEMG using a large number of intact subjects and amputees. We tested convolutional networks for the classification of an average of 50 hand movements in 67 intact subjects and 11 transradial amputees. The simple architecture of the neural network allowed to make several tests in order to evaluate the effect of pre-processing, layer architecture, data augmentation and optimization. The classification results are compared with a set of classical classification methods applied on the same datasets. The classification accuracy obtained with convolutional neural networks using the proposed architecture is higher than the average results obtained with the classical classification methods, but lower than the results obtained with the best reference methods in our tests. The results show that convolutional neural networks with a very simple architecture can produce accurate results comparable to the average classical classification methods. They show that several factors (including pre-processing, the architecture of the net and the optimization parameters) can be fundamental for the analysis of sEMG data. Larger networks can achieve higher accuracy on computer vision and object recognition tasks. This fact suggests that it may be interesting to evaluate if larger networks can increase sEMG classification accuracy too. PMID:27656140

Esthetic, functional, and prosthetic outcomes with implant-retained finger prostheses.

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Aydin, Cemal; Nemli, Secil Karakoca; Yilmaz, Handan

2013-04-01

Traumatic amputation of fingers results in a serious impairment of hand function and affects the psychological status of the patients. The implant-retained finger prostheses are an alternative treatment. The aim of this case report is to represent the use of osseointegrated implants for retention of finger prostheses in a patient with amputated thumb and index finger. Dental implants were placed in the residual bone of the fingers using two-stage surgery. Custom-made attachments were used to provide retention between implants and silicone prostheses. Prosthetic fingernails were made of composite resin material. After 6 months, implants were clinically successful, and the patient was satisfied with the appearance and the function of the prostheses. The complications of broken prosthetic nail and mild discoloration were observed. Reconstruction of amputated fingers with implant-retained prosthesis is a worthwhile treatment providing esthetic, functional, and psychological benefits, although some complications might be experienced. Clinical relevance Implant-retained finger prostheses are an acceptable treatment modality for patients with amputated fingers. Evaluating implant prognosis, functional results and prosthetic results of the patients are necessary to address the benefits and complications of the treatment.

Overview: Mechanism and Control of a Prosthetic Arm.

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Kulkarni, Tushar; Uddanwadiker, Rashmi

2015-09-01

Continuous growth in industrialization and lack of awareness in safety parameters the cases of amputations are growing. The search of safer, simpler and automated prosthetic arms for managing upper limbs is expected. Continuous efforts have been made to design and develop prosthetic arms ranging from simple harness actuated to automated mechanisms with various control options. However due the cost constraints, the automated prosthetic arms are still out of the reach of needy people. Recent data have shown that there is a wide scope to develop a low cost and light weight upper limb prosthesis. This review summarizes the various designs methodologies, mechanisms and control system developed by the researchers and the advances therein. Educating the patient to develop acceptability to prosthesis and using the same for the most basic desired functions of human hand, post amputation care and to improve patient's independent life is equally important. In conclusion it can be interpreted that there is a wide scope in design in an adaptive mechanism for opening and closing of the fingers using other methods of path and position synthesis. Simple mechanisms and less parts may optimize the cost factor. Reduction in the weight of the prosthesis may be achieved using polymers used for engineering applications. Control system will remain never ending challenge for the researchers, but it is essential to maintain the simplicity from the patients perspective.

Prevention of Prosthetic Dentistry

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Eremin O.V.

2011-03-01

Full Text Available Prevention in prosthetic dentistry is not just a regular oral hygiene and the prevention of caries in the early stages of its development. The initial goal of orthopedic and dental should be the ability to convey to the patient's sense of pros-thetics that proteziruya one saved more. An example is included prosthetic dental arch defects with bridges or single artificial crowns on implants that will prevent movement of teeth and the continuity of the dentition

Assessing user acceptance towards automated and conventional sink use for hand decontamination using the technology acceptance model.

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Dawson, Carolyn H; Mackrill, Jamie B; Cain, Rebecca

2017-12-01

Hand hygiene (HH) prevents harmful contaminants spreading in settings including domestic, health care and food handling. Strategies to improve HH range from behavioural techniques through to automated sinks that ensure hand surface cleaning. This study aimed to assess user experience and acceptance towards a new automated sink, compared to a normal sink. An adapted version of the technology acceptance model (TAM) assessed each mode of handwashing. A within-subjects design enabled N = 46 participants to evaluate both sinks. Perceived Ease of Use and Satisfaction of Use were significantly lower for the automated sink, compared to the conventional sink (p technology. We provide recommendations for future HH technology development to contribute a positive user experience, relevant to technology developers, ergonomists and those involved in HH across all sectors. Practitioner Summary: The need to facilitate timely, effective hand hygiene to prevent illness has led to a rise in automated handwashing systems across different contexts. User acceptance is a key factor in system uptake. This paper applies the technology acceptance model as a means to explore and optimise the design of such systems.

Prosthetics socket that incorporates an air splint system focusing on dynamic interface pressure.

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Razak, Nasrul Anuar Abd; Osman, Noor Azuan Abu; Gholizadeh, Hossein; Ali, Sadeeq

2014-08-01

The interface pressure between the residual limb and prosthetic socket has a significant effect on an amputee's satisfaction and comfort. This paper presents the design and performance of a new prosthetic socket that uses an air splint system. The air splint prosthetic socket system was implemented by combining the air splint with a pressure sensor that the transhumeral user controls through the use of a microcontroller. The modular construction of the system developed allows the FSR pressure sensors that are placed inside the air splint socket to determine the required size and fitting for the socket used. Fifteen transhumeral amputees participated in the study. The subject's dynamic pressure on the socket that's applied while wearing the air splint systems was recorded using F-socket transducers and microcontroller analysis. The values collected by the F-socket sensor for the air splint prosthetic socket system were determined accordingly by comparing the dynamic pressure applied using statically socket. The pressure volume of the air splint fluctuated and was recorded at an average of 38 kPa (2.5) to 41 kPa (1.3) over three hours. The air splint socket might reduce the pressure within the interface of residual limb. This is particularly important during the daily life activities and may reduce the pain and discomfort at the residual limb in comparison to the static socket. The potential development of an auto-adjusted socket that uses an air splint system as the prosthetic socket will be of interest to researchers involved in rehabilitation engineering, prosthetics and orthotics.

Psychometric evaluation of self-report outcome measures for prosthetic applications

OpenAIRE

Hafner, Brian J.; Morgan, Sara J.; Askew, Robert L.; Salem, Rana

2016-01-01

Documentation of clinical outcomes is increasingly expected in delivery of prosthetic services and devices. However, many outcome measures suitable for use in clinical care and research have not been psychometrically tested with prosthesis users. The aim of this study was to determine test-retest reliability, mode-of-administration (MoA) equivalence, standard error of measurement (SEM), and minimal detectable change (MDC) of standardized, self-report instruments that assess constructs of impo...

Object discrimination using optimized multi-frequency auditory cross-modal haptic feedback.

Science.gov (United States)

Gibson, Alison; Artemiadis, Panagiotis

2014-01-01

As the field of brain-machine interfaces and neuro-prosthetics continues to grow, there is a high need for sensor and actuation mechanisms that can provide haptic feedback to the user. Current technologies employ expensive, invasive and often inefficient force feedback methods, resulting in an unrealistic solution for individuals who rely on these devices. This paper responds through the development, integration and analysis of a novel feedback architecture where haptic information during the neural control of a prosthetic hand is perceived through multi-frequency auditory signals. Through representing force magnitude with volume and force location with frequency, the feedback architecture can translate the haptic experiences of a robotic end effector into the alternative sensory modality of sound. Previous research with the proposed cross-modal feedback method confirmed its learnability, so the current work aimed to investigate which frequency map (i.e. frequency-specific locations on the hand) is optimal in helping users distinguish between hand-held objects and tasks associated with them. After short use with the cross-modal feedback during the electromyographic (EMG) control of a prosthetic hand, testing results show that users are able to use audial feedback alone to discriminate between everyday objects. While users showed adaptation to three different frequency maps, the simplest map containing only two frequencies was found to be the most useful in discriminating between objects. This outcome provides support for the feasibility and practicality of the cross-modal feedback method during the neural control of prosthetics.

Formation of social and household skills in children with hand defects.

Science.gov (United States)

Klimon, Nataly; Koryukov, Alexander; Loseva, Nina; Starobina, Elena

2015-08-01

The aim of this study was to consider the peculiarities of forming social and household skills, and the criteria for their evaluation, as well as an assessment of functional capacity, in children with hand defects both before and after surgical treatment and rehabilitation courses using a system of games. We elaborated and implemented a program of social rehabilitation of preschool children with congenital and acquired hand defects for the development of their functional capabilities and the formation of social and household skills after surgical treatment and prosthetics using play therapy methods. As part of this work, 140 preschool children aged 3-7 years underwent social rehabilitation. Most of the children had congenital hand defects-122 children (87 %): 96 children (79 %) with ectrodactylia, adactylia, hypoplasia, aplasia, hand splitting, club hand, or partial gigantism; 26 children (21 %) with congenital syndactylism and constricted bonds and 18 children (13 %) with acquired defects (burn deformity, amputation). 110 children (79 %) had reached the stage of surgical correction; 30 children (21 %) reached the stage of prosthetics. Most of the children participating in the experiment (78 children, 56 %) had defects of fingers on one hand. The program aimed at solving specific rehabilitation tasks: formation and improvement of all possible types of grip under the existing defect including those after surgery and prosthetics; development of tactile sensations in fingers; development of fine motor skills; increase in range of motion in all joints of the damaged hand; development of attention and concentration; formation of social and household skills appropriate to age; and development of the ability to achieve the set task. Analysis of the level of social and household skills of children with hand defects undergoing rehabilitation treatment at the hospital depending on the age prior to medical and social rehabilitation showed that preschool children with

EEG Mind Controlled Smart Prosthetic Arm – A Comprehensive Study

Directory of Open Access Journals (Sweden)

Taha Beyrouthy

2017-06-01

Full Text Available Recently, the field of prosthetics has seen many accomplishments especially with the integration of technological advancements. In this paper, different arm types (robotic, surgical, bionic, prosthetic and static are analyzed in terms of resistance, usage, flexibility, cost and potential. Most of these techniques have some problems; they are extremely expensive, hard to install and maintain and may require surgery. Therefore, our work introduces the initial design of an EEG mind controlled smart prosthetic arm. The arm is controlled by the brain commands, obtained from an electroencephalography (EEG headset, and equipped with a network of smart sensors and actuators that give the patient intelligent feedback about the surrounding environment and the object in contact. This network provides the arm with normal hand functionality, smart reflexes and smooth movements. Various types of sensors are used including temperature, pressure, ultrasonic proximity sensors, accelerometers, potentiometers, strain gauges and gyroscopes. The arm is completely 3D printed built from various lightweight and high strength materials that can handle high impacts and fragile elements as well. Our project requires the use of nine servomotors installed at different places in the arm. Therefore, the static and dynamic modes of servomotors are analyzed. The total cost of the project is estimated to be relatively cheap compared to other previously built arms. Many scenarios are analyzed corresponding to the actions that the prosthetic arm can perform, and an algorithm is created to match these scenarios. Experimental results show that the proposed EEG Mind-controlled Arm is a promising alternative for current solutions that require invasive and expensive surgical procedures.

Learning from demonstration: Teaching a myoelectric prosthesis with an intact limb via reinforcement learning.

Science.gov (United States)

Vasan, Gautham; Pilarski, Patrick M

2017-07-01

Prosthetic arms should restore and extend the capabilities of someone with an amputation. They should move naturally and be able to perform elegant, coordinated movements that approximate those of a biological arm. Despite these objectives, the control of modern-day prostheses is often nonintuitive and taxing. Existing devices and control approaches do not yet give users the ability to effect highly synergistic movements during their daily-life control of a prosthetic device. As a step towards improving the control of prosthetic arms and hands, we introduce an intuitive approach to training a prosthetic control system that helps a user achieve hard-to-engineer control behaviours. Specifically, we present an actor-critic reinforcement learning method that for the first time promises to allow someone with an amputation to use their non-amputated arm to teach their prosthetic arm how to move through a wide range of coordinated motions and grasp patterns. We evaluate our method during the myoelectric control of a multi-joint robot arm by non-amputee users, and demonstrate that by using our approach a user can train their arm to perform simultaneous gestures and movements in all three degrees of freedom in the robot's hand and wrist based only on information sampled from the robot and the user's above-elbow myoelectric signals. Our results indicate that this learning-from-demonstration paradigm may be well suited to use by both patients and clinicians with minimal technical knowledge, as it allows a user to personalize the control of his or her prosthesis without having to know the underlying mechanics of the prosthetic limb. These preliminary results also suggest that our approach may extend in a straightforward way to next-generation prostheses with precise finger and wrist control, such that these devices may someday allow users to perform fluid and intuitive movements like playing the piano, catching a ball, and comfortably shaking hands.

Can We Achieve Intuitive Prosthetic Elbow Control Based on Healthy Upper Limb Motor Strategies?

Directory of Open Access Journals (Sweden)

Manelle Merad

2018-02-01

Full Text Available Most transhumeral amputees report that their prosthetic device lacks functionality, citing the control strategy as a major limitation. Indeed, they are required to control several degrees of freedom with muscle groups primarily used for elbow actuation. As a result, most of them choose to have a one-degree-of-freedom myoelectric hand for grasping objects, a myoelectric wrist for pronation/supination, and a body-powered elbow. Unlike healthy upper limb movements, the prosthetic elbow joint angle, adjusted prior to the motion, is not involved in the overall upper limb movements, causing the rest of the body to compensate for the lack of mobility of the prosthesis. A promising solution to improve upper limb prosthesis control exploits the residual limb mobility: like in healthy movements, shoulder and prosthetic elbow motions are coupled using inter-joint coordination models. The present study aims to test this approach. A transhumeral amputated individual used a prosthesis with a residual limb motion-driven elbow to point at targets. The prosthetic elbow motion was derived from IMU-based shoulder measurements and a generic model of inter-joint coordinations built from healthy individuals data. For comparison, the participant also performed the task while the prosthetic elbow was implemented with his own myoelectric control strategy. The results show that although the transhumeral amputated participant achieved the pointing task with a better precision when the elbow was myoelectrically-controlled, he had to develop large compensatory trunk movements. Automatic elbow control reduced trunk displacements, and enabled a more natural body behavior with synchronous shoulder and elbow motions. However, due to socket impairments, the residual limb amplitudes were not as large as those of healthy shoulder movements. Therefore, this work also investigates if a control strategy whereby prosthetic joints are automatized according to healthy individuals

GIANT PROSTHETIC VALVE THROMBUS

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Prashanth Kumar

2015-04-01

Full Text Available Mechanical prosthetic valves are predisposed to bleeding, thrombosis & thromboembolic complications. Overall incidence of thromboembolic complications is 1% per year who are on oral anticoagulants, whereas bleeding complications incidence is 0.5% to 6.6% per year. 1, 2 Minimization of Scylla of thromboembolic & Charybdis of bleeding complication needs a balancing act of optimal antithrombotic therapy. We are reporting a case of middle aged male patient with prosthetic mitral valve presenting in heart failure. Patient had discontinued anticoagulants, as he had subdural hematoma in the past. He presented to our institute with a giant prosthetic valve thrombus.

Sensory feedback in upper limb prosthetics.

Science.gov (United States)

Antfolk, Christian; D'Alonzo, Marco; Rosén, Birgitta; Lundborg, Göran; Sebelius, Fredrik; Cipriani, Christian

2013-01-01

One of the challenges facing prosthetic designers and engineers is to restore the missing sensory function inherit to hand amputation. Several different techniques can be employed to provide amputees with sensory feedback: sensory substitution methods where the recorded stimulus is not only transferred to the amputee, but also translated to a different modality (modality-matched feedback), which transfers the stimulus without translation and direct neural stimulation, which interacts directly with peripheral afferent nerves. This paper presents an overview of the principal works and devices employed to provide upper limb amputees with sensory feedback. The focus is on sensory substitution and modality matched feedback; the principal features, advantages and disadvantages of the different methods are presented.

Prosthetic Joint Infections

Science.gov (United States)

Aslam, Saima; Darouiche, Rabih O.

2012-01-01

Prosthetic joint infections represent a major therapeutic challenge for both healthcare providers and patients. This paper reviews the predisposing factors, pathogenesis, microbiology, diagnosis, treatment and prophylaxis of prosthetic joint infection. The most optimal management strategy should be identified based on a number of considerations including type and duration of infection, antimicrobial susceptibility of the infecting pathogen, condition of infected tissues and bone stock, patient wishes and functional status. PMID:22847032

An Analysis of Intrinsic and Extrinsic Hand Muscle EMG for Improved Pattern Recognition Control.

Science.gov (United States)

Adewuyi, Adenike A; Hargrove, Levi J; Kuiken, Todd A

2016-04-01

Pattern recognition control combined with surface electromyography (EMG) from the extrinsic hand muscles has shown great promise for control of multiple prosthetic functions for transradial amputees. There is, however, a need to adapt this control method when implemented for partial-hand amputees, who possess both a functional wrist and information-rich residual intrinsic hand muscles. We demonstrate that combining EMG data from both intrinsic and extrinsic hand muscles to classify hand grasps and finger motions allows up to 19 classes of hand grasps and individual finger motions to be decoded, with an accuracy of 96% for non-amputees and 85% for partial-hand amputees. We evaluated real-time pattern recognition control of three hand motions in seven different wrist positions. We found that a system trained with both intrinsic and extrinsic muscle EMG data, collected while statically and dynamically varying wrist position increased completion rates from 73% to 96% for partial-hand amputees and from 88% to 100% for non-amputees when compared to a system trained with only extrinsic muscle EMG data collected in a neutral wrist position. Our study shows that incorporating intrinsic muscle EMG data and wrist motion can significantly improve the robustness of pattern recognition control for application to partial-hand prosthetic control.

Deep learning-based artificial vision for grasp classification in myoelectric hands

Science.gov (United States)

Ghazaei, Ghazal; Alameer, Ali; Degenaar, Patrick; Morgan, Graham; Nazarpour, Kianoush

2017-06-01

Objective. Computer vision-based assistive technology solutions can revolutionise the quality of care for people with sensorimotor disorders. The goal of this work was to enable trans-radial amputees to use a simple, yet efficient, computer vision system to grasp and move common household objects with a two-channel myoelectric prosthetic hand. Approach. We developed a deep learning-based artificial vision system to augment the grasp functionality of a commercial prosthesis. Our main conceptual novelty is that we classify objects with regards to the grasp pattern without explicitly identifying them or measuring their dimensions. A convolutional neural network (CNN) structure was trained with images of over 500 graspable objects. For each object, 72 images, at {{5}\\circ} intervals, were available. Objects were categorised into four grasp classes, namely: pinch, tripod, palmar wrist neutral and palmar wrist pronated. The CNN setting was first tuned and tested offline and then in realtime with objects or object views that were not included in the training set. Main results. The classification accuracy in the offline tests reached 85 % for the seen and 75 % for the novel objects; reflecting the generalisability of grasp classification. We then implemented the proposed framework in realtime on a standard laptop computer and achieved an overall score of 84 % in classifying a set of novel as well as seen but randomly-rotated objects. Finally, the system was tested with two trans-radial amputee volunteers controlling an i-limb UltraTM prosthetic hand and a motion controlTM prosthetic wrist; augmented with a webcam. After training, subjects successfully picked up and moved the target objects with an overall success of up to 88 % . In addition, we show that with training, subjects’ performance improved in terms of time required to accomplish a block of 24 trials despite a decreasing level of visual feedback. Significance. The proposed design constitutes a substantial

Prosthetic Aortic Valve Fixation Study: 48 Replacement Valves Analyzed Using Digital Pressure Mapping.

Science.gov (United States)

Lee, Candice Y; Wong, Joshua K; Ross, Ronald E; Liu, David C; Khabbaz, Kamal R; Martellaro, Angelo J; Gorea, Heather R; Sauer, Jude S; Knight, Peter A

Prostheses attachment is critical in aortic valve replacement surgery, yet reliable prosthetic security remains a challenge. Accurate techniques to analyze prosthetic fixation pressures may enable the use of fewer sutures while reducing the risk of paravalvular leaks (PVL). Customized digital thin film pressure transducers were sutured between aortic annulus models and 21-mm bioprosthetic valves with 15 × 4-mm, 12 × 4-mm, or 9 × 6-mm-wide pledgeted mattress sutures. Simulating open and minimally invasive access, 4 surgeons, blinded to data acquisition, each secured 12 valves using manual knot-tying (hand-tied [HT] or knot-pusher [KP]) or automated titanium fasteners (TFs). Real-time pressure measurements and times were recorded. Two-dimensional (2D) and 3D pressure maps were generated for all valves. Pressures less than 80 mm Hg were considered at risk for PVL. Pressures under each knot (intrasuture) fell less than 80 mm Hg for 12 of 144 manual knots (5/144 HT, 7/144 KP) versus 0 of 288 TF (P prosthetic valve security.

Pregnancy after Prosthetic Aortic Valve Replacement: How Do We Monitor Prosthetic Valvular Function during Pregnancy?

Directory of Open Access Journals (Sweden)

Nicole Sahasrabudhe

2018-01-01

Full Text Available Background. With modern medicine, many women after structural heart repair are deciding to experience pregnancy. There is a need for further study to identify normal echocardiographic parameters to better assess prosthetic valvular function in pregnancy. In addition, a multidisciplinary approach is essential in managing pregnant patients with complex cardiac conditions. Case. A 22-year-old nulliparous woman with an aortic valve replacement 18 months prior to her pregnancy presented to prenatal care at 20-week gestation. During her prenatal care, serial echocardiography showed a significant increase in the mean gradient across the prosthetic aortic valve. Multidisciplinary management and a serial echocardiography played an integral role in her care that resulted in a successful spontaneous vaginal delivery without complications. Conclusion. Further characterization of the normal echocardiographic parameters in pregnant patients with prosthetic valves is critical to optimize prenatal care for this patient population. This case report is novel in that serial echocardiograms were obtained throughout prenatal care, which showed significant changes across the prosthetic aortic valve. Teaching Points. (1 Further study is needed to identify normal echocardiographic parameters to best assess prosthetic valvular function in pregnancy. (2 Multidisciplinary management is encouraged to optimize prenatal care for women with prosthetic aortic valve replacements.

Energy storage and release of prosthetic feet. Part 1: biomechanical analysis related to user benefits

NARCIS (Netherlands)

Postema, K.; Hermens, Hermanus J.; de Vries, J.; de Vries, J.; Koopman, Hubertus F.J.M.; Eisma, W.H.

1997-01-01

The energy storing and releasing behaviour of 2 energy storing feet (ESF) and 2 conventional prosthetic feet (CF) were compared (ESF: Otto Bock Dynamic Pro and Hanger Quantum; CF: Otto Bock Multi Axial and Otto Bock Lager). Ten trans-tibial amputees were selected. The study was designed as a

Prosthetic component segmentation with blur compensation: a fast method for 3D fluoroscopy.

Science.gov (United States)

Tarroni, Giacomo; Tersi, Luca; Corsi, Cristiana; Stagni, Rita

2012-06-01

A new method for prosthetic component segmentation from fluoroscopic images is presented. The hybrid approach we propose combines diffusion filtering, region growing and level-set techniques without exploiting any a priori knowledge of the analyzed geometry. The method was evaluated on a synthetic dataset including 270 images of knee and hip prosthesis merged to real fluoroscopic data simulating different conditions of blurring and illumination gradient. The performance of the method was assessed by comparing estimated contours to references using different metrics. Results showed that the segmentation procedure is fast, accurate, independent on the operator as well as on the specific geometrical characteristics of the prosthetic component, and able to compensate for amount of blurring and illumination gradient. Importantly, the method allows a strong reduction of required user interaction time when compared to traditional segmentation techniques. Its effectiveness and robustness in different image conditions, together with simplicity and fast implementation, make this prosthetic component segmentation procedure promising and suitable for multiple clinical applications including assessment of in vivo joint kinematics in a variety of cases.

Multi-User Virtual Reality Therapy for Post-Stroke Hand Rehabilitation at Home

Directory of Open Access Journals (Sweden)

Daria Tsoupikova

2016-04-01

Full Text Available Our paper describes the development of a novel multi-user virtual reality (VR system for post-stroke rehabilitation that can be used independently in the home to improve upper extremity motor function. This is the pre-clinical phase of an ongoing collaborative, interdisciplinary research project at the Rehabilitation Institute of Chicago involving a team of engineers, researchers, occupational therapists and artists. This system was designed for creative collaboration within a virtual environment to increase patients' motivation, further engagement and to alleviate the impact of social isolation following stroke. This is a low-cost system adapted to everyday environments and designed to run on a personal computer that combines three VR environments with audio integration, wireless Kinect tracking and hand motion tracking sensors. Three different game exercises for this system were developed to encourage repetitive task practice, collaboration and competitive interaction. The system is currently being tested with 15 subjects in three settings: a multi-user VR, a single-user VR and at a tabletop with standard exercises to examine the level of engagement and to compare resulting functional performance across methods. We hypothesize that stroke survivors will become more engaged in therapy when training with a multi-user VR system and this will translate into greater gains.

Prosthetic vascular graft infection and prosthetic joint infection caused by Pseudomonas stutzeri.

Science.gov (United States)

Bonares, Michael J; Vaisman, Alon; Sharkawy, Abdu

2016-01-01

Pseudomonas stutzeri is infrequently isolated from clinical specimens, and if isolated, more likely represents colonization or contamination rather than infection. Despite this, there are dozens of case reports which describe clinically significant P. stutzeri infections at variable sites. A 69-year-old man had a P. stutzeri infection of a prosthetic vascular graft infection, which he received in Panama City. He was successfully treated with a single antipseudomonal agent for 6 weeks and the removal of the infected vascular graft. A 70-year-old man had a P. stutzeri infection of a prosthetic joint, which was successfully treated with a single anti-pseudomonal agent for 6 weeks. There is only one other documented case of a prosthetic vascular graft infection secondary to P. stutzeri . There are 5 documented cases of P. stutzeri prosthetic joint infections. The previous cases were treated with antibiotics and variably, source control with the removal of prosthetic material. Most cases of P. stutzeri infection are due to exposure in health care settings. Immunocompromised states such as HIV or hematological and solid tumor malignancies are risk factors for P. stutzeri infection. Infections caused by P. stutzeri are far less frequent and less fatal than those caused by P. aeruginosa. The etiology of a P. stutzeri infection could be exposure to soil and water, but also contaminated material in the health care setting or an immunocompromised state. Iatrogenic infections that are secondary to health care tourism are a potential cause of fever in the returned traveler.

Hand posture classification using electrocorticography signals in the gamma band over human sensorimotor brain areas

Science.gov (United States)

Chestek, Cynthia A.; Gilja, Vikash; Blabe, Christine H.; Foster, Brett L.; Shenoy, Krishna V.; Parvizi, Josef; Henderson, Jaimie M.

2013-04-01

Objective. Brain-machine interface systems translate recorded neural signals into command signals for assistive technology. In individuals with upper limb amputation or cervical spinal cord injury, the restoration of a useful hand grasp could significantly improve daily function. We sought to determine if electrocorticographic (ECoG) signals contain sufficient information to select among multiple hand postures for a prosthetic hand, orthotic, or functional electrical stimulation system.Approach. We recorded ECoG signals from subdural macro- and microelectrodes implanted in motor areas of three participants who were undergoing inpatient monitoring for diagnosis and treatment of intractable epilepsy. Participants performed five distinct isometric hand postures, as well as four distinct finger movements. Several control experiments were attempted in order to remove sensory information from the classification results. Online experiments were performed with two participants. Main results. Classification rates were 68%, 84% and 81% for correct identification of 5 isometric hand postures offline. Using 3 potential controls for removing sensory signals, error rates were approximately doubled on average (2.1×). A similar increase in errors (2.6×) was noted when the participant was asked to make simultaneous wrist movements along with the hand postures. In online experiments, fist versus rest was successfully classified on 97% of trials; the classification output drove a prosthetic hand. Online classification performance for a larger number of hand postures remained above chance, but substantially below offline performance. In addition, the long integration windows used would preclude the use of decoded signals for control of a BCI system. Significance. These results suggest that ECoG is a plausible source of command signals for prosthetic grasp selection. Overall, avenues remain for improvement through better electrode designs and placement, better participant training

Isolated Lactobacillus chronic prosthetic knee infection.

Science.gov (United States)

Bennett, David M; Shekhel, Tatyana; Radelet, Matt; Miller, Michael D

2014-01-01

Lactobacillus is a gram-positive rod bacteria found primarily in the gastrointestinal and female genital tracts. Prosthetic infections in implants are being increasingly reported. The authors present a case of a 58-year-old patient with Lactobacillus septic prosthetic knee joint infection. To the authors’ knowledge, this is the first reported case of chronic prosthetic knee infection with isolated Lactobacillus species. Lactobacillus has been most commonly implicated with bacteremia and endocarditis and rarely with pneumonia, meningitis, and endovascular infection, and a vast majority of the cases are reported in immunocompromised patients. In the current case, diabetes mellitus, hepatitis, malnutrition, anemia, and liver failure were comorbid conditions, placing the patient at increased risk of infection. The findings suggest that further case series are necessary to establish the significance of Lactobacillus as an etiologic agent in chronic low-virulence, and potentially vancomycin-resistant, prosthetic joint infection. The need also exists for further research aimed at the risk of prosthetic joint infection with oral intake of certain probiotic foods and supplements. The goal of this case report is to bring to light the potential of this organism to be a cause of subtle chronic prosthetic joint infection.

Computer Aided Facial Prosthetics Manufacturing System

Directory of Open Access Journals (Sweden)

Peng H.K.

2016-01-01

Full Text Available Facial deformities can impose burden to the patient. There are many solutions for facial deformities such as plastic surgery and facial prosthetics. However, current fabrication method of facial prosthetics is high-cost and time consuming. This study aimed to identify a new method to construct a customized facial prosthetic. A 3D scanner, computer software and 3D printer were used in this study. Results showed that the new developed method can be used to produce a customized facial prosthetics. The advantages of the developed method over the conventional process are low cost, reduce waste of material and pollution in order to meet the green concept.

Humans can integrate feedback of discrete events in their sensorimotor control of a robotic hand.

Science.gov (United States)

Cipriani, Christian; Segil, Jacob L; Clemente, Francesco; ff Weir, Richard F; Edin, Benoni

2014-11-01

Providing functionally effective sensory feedback to users of prosthetics is a largely unsolved challenge. Traditional solutions require high band-widths for providing feedback for the control of manipulation and yet have been largely unsuccessful. In this study, we have explored a strategy that relies on temporally discrete sensory feedback that is technically simple to provide. According to the Discrete Event-driven Sensory feedback Control (DESC) policy, motor tasks in humans are organized in phases delimited by means of sensory encoded discrete mechanical events. To explore the applicability of DESC for control, we designed a paradigm in which healthy humans operated an artificial robot hand to lift and replace an instrumented object, a task that can readily be learned and mastered under visual control. Assuming that the central nervous system of humans naturally organizes motor tasks based on a strategy akin to DESC, we delivered short-lasting vibrotactile feedback related to events that are known to forcefully affect progression of the grasp-lift-and-hold task. After training, we determined whether the artificial feedback had been integrated with the sensorimotor control by introducing short delays and we indeed observed that the participants significantly delayed subsequent phases of the task. This study thus gives support to the DESC policy hypothesis. Moreover, it demonstrates that humans can integrate temporally discrete sensory feedback while controlling an artificial hand and invites further studies in which inexpensive, noninvasive technology could be used in clever ways to provide physiologically appropriate sensory feedback in upper limb prosthetics with much lower band-width requirements than with traditional solutions.

The role of osteoblasts in peri-prosthetic osteolysis.

LENUS (Irish Health Repository)

O'Neill, S C

2013-08-01

Peri-prosthetic osteolysis and subsequent aseptic loosening is the most common reason for revising total hip replacements. Wear particles originating from the prosthetic components interact with multiple cell types in the peri-prosthetic region resulting in an inflammatory process that ultimately leads to peri-prosthetic bone loss. These cells include macrophages, osteoclasts, osteoblasts and fibroblasts. The majority of research in peri-prosthetic osteolysis has concentrated on the role played by osteoclasts and macrophages. The purpose of this review is to assess the role of the osteoblast in peri-prosthetic osteolysis. In peri-prosthetic osteolysis, wear particles may affect osteoblasts and contribute to the osteolytic process by two mechanisms. First, particles and metallic ions have been shown to inhibit the osteoblast in terms of its ability to secrete mineralised bone matrix, by reducing calcium deposition, alkaline phosphatase activity and its ability to proliferate. Secondly, particles and metallic ions have been shown to stimulate osteoblasts to produce pro inflammatory mediators in vitro. In vivo, these mediators have the potential to attract pro-inflammatory cells to the peri-prosthetic area and stimulate osteoclasts to absorb bone. Further research is needed to fully define the role of the osteoblast in peri-prosthetic osteolysis and to explore its potential role as a therapeutic target in this condition.

Effect of power-assisted hand-rim wheelchair propulsion on shoulder load in experienced wheelchair users : A pilot study with an instrumented wheelchair

NARCIS (Netherlands)

Kloosterman, Marieke G. M.; Buurke, Jaap H.; de Vries, Wiebe; Van der Woude, Lucas H. V.; Rietman, Johan S.

2015-01-01

This study aims to compare hand-rim and power-assisted hand-rim propulsion on potential risk factors for shoulder overuse injuries: intensity and repetition of shoulder loading and force generation in the extremes of shoulder motion. Eleven experienced hand-rim wheelchair users propelled an

Effect of power-assisted hand-rim wheelchair propulsion on shoulder load in experienced wheelchair users: A pilot study with an instrumented wheelchair

NARCIS (Netherlands)

Kloosterman, Marieke; Buurke, Jaap; de Vries, W.; de Vries, W.; van der Woude, L.H.V.; Rietman, Johan Swanik

2015-01-01

This study aims to compare hand-rim and power-assisted hand-rim propulsion on potential risk factors for shoulder overuse injuries: intensity and repetition of shoulder loading and force generation in the extremes of shoulder motion. Eleven experienced hand-rim wheelchair users propelled an

Force-directed design of a voluntary closing hand prosthesis

NARCIS (Netherlands)

De Visser, H.; Herder, J.L.

2000-01-01

This paper presents the design of a body-powered voluntary closing prosthetic hand. It is argued that the movement of the fingers before establishing a grip is much less relevant for good control of the object held than the distribution of forces once the object has been contacted. Based on this

Pre-prosthetic surgery: Mandible

Directory of Open Access Journals (Sweden)

Veeramalai Naidu Devaki

2012-01-01

Full Text Available Pre-prosthetic surgery is that part of oral and maxillofacial surgery which restores oral function and facial form. This is concerned with surgical modification of the alveolar process and its surrounding structures to enable the fabrication of a well-fitting, comfortable, and esthetic dental prosthesis. The ultimate goal of pre-prosthetic surgery is to prepare a mouth to receive a dental prosthesis by redesigning and smoothening bony edges.

Guide to prosthetic cardiac valves

International Nuclear Information System (INIS)

Morse, D.; Steiner, R.M.; Fernandez, J.

1985-01-01

This book contains 10 chapters. Some of the chapter titles are: The development of artificial heart valves: Introduction and historical perspective; The radiology of prosthetic heart valves; The evaluation of patients for prosthetic valve implantation; Pathology of cardiac valve replacement; and Bioengineering of mechanical and biological heart valve substitutes

Prosthetic status and prosthetic need among the patients attending various dental institutes of ahmedabad and gandhinagar district, gujarat.

Science.gov (United States)

Shah, Vrinda R; Shah, Darshana N; Parmar, Chaitanya H

2012-09-01

The oral health being an integral part for the healthy living, necessity of disability limitation and rehabilitation in oral health has taken a paramount role. To assess the prosthetic status and to evaluate the prosthetic needs of the patients attending various institutes of Ahmedabad and Gandhinagar district. A total of 510 (264 males and 246 females) subjects at various dental institutes were examined in the study. A survey proforma was prepared with the help of WHO oral health assessment form (1997). Prosthetic status and prosthetic treatment need was recorded. Out of 510, any type of Edentulousness was 322 (63 %). Among them, 254 (49.8 %) were partially edentulous while 68 (13.3 %) were completely edentulous. Only 69 (13 %) were having any prosthesis in upper arch while only 80 (16 %) were having any prosthesis in lower arch. Need for any type of prosthesis in upper and lower arch was 55 and 60 % in males and females, respectively. In lower social class group need of prosthesis in upper and lower arch was 62 and 63 %, respectively. It was found that prosthetic status and prosthetic treatment need increased with increase in age. Steps should be taken to overcome this disparity and more emphasis should be given to meet the felt need of the people through government and non government organizations to improve the oral health. The unmet prosthetic treatment need should be met to rehabilitate needy people so that their disability may be limited.

iHand: an interactive bare-hand-based augmented reality interface on commercial mobile phones

Science.gov (United States)

Choi, Junyeong; Park, Jungsik; Park, Hanhoon; Park, Jong-Il

2013-02-01

The performance of mobile phones has rapidly improved, and they are emerging as a powerful platform. In many vision-based applications, human hands play a key role in natural interaction. However, relatively little attention has been paid to the interaction between human hands and the mobile phone. Thus, we propose a vision- and hand gesture-based interface in which the user holds a mobile phone in one hand but sees the other hand's palm through a built-in camera. The virtual contents are faithfully rendered on the user's palm through palm pose estimation, and reaction with hand and finger movements is achieved that is recognized by hand shape recognition. Since the proposed interface is based on hand gestures familiar to humans and does not require any additional sensors or markers, the user can freely interact with virtual contents anytime and anywhere without any training. We demonstrate that the proposed interface works at over 15 fps on a commercial mobile phone with a 1.2-GHz dual core processor and 1 GB RAM.

Detecting users handedness for ergonomic adaptation of mobile user interfaces

DEFF Research Database (Denmark)

Löchtefeld, Markus; Schardt, Phillip; Krüger, Antonio

2015-01-01

) for users with average hand sizes. One solution is to offer adaptive user interfaces for such one-handed interactions. These modes have to be triggered manually and thus induce a critical overhead. They are further designed to bring all content closer, regardless of whether the phone is operated...... with the left or right hand. In this paper, we present an algorithm that allows determining the users' interacting hand from their unlocking behavior. Our algorithm correctly distinguishes one- and twohanded usage as well as left- and right handed unlocking in 98.51% of all cases. This is achieved through a k...

Bio-inspired mechanical design of a tendon-driven dexterous prosthetic hand.

Science.gov (United States)

Controzzi, Marco; Cipriani, Christian; Jehenne, Beryl; Donati, Marco; Carrozza, Maria Chiara

2010-01-01

This paper presents the preliminary design of a new dexterous upper-limb prosthesis provided with a novel anthropomorphic hand, a compact wrist based on bevel gears and a modular forearm able to cover different levels of upper-limb amputations. The hand has 20 DoFs and 11 motors, with a dexterous three fingered subsystem composed by a fully actuated thumb, and an hybrid index and middle fingers to enable dexterous manipulation and enhance grasp performance.

Biomechanical characteristics, patient preference and activity level with different prosthetic feet: a randomized double blind trial with laboratory and community testing.

Science.gov (United States)

Raschke, Silvia U; Orendurff, Michael S; Mattie, Johanne L; Kenyon, David E A; Jones, O Yvette; Moe, David; Winder, Lorne; Wong, Angie S; Moreno-Hernández, Ana; Highsmith, M Jason; J Sanderson, David; Kobayashi, Toshiki

2015-01-02

Providing appropriate prosthetic feet to those with limb loss is a complex and subjective process influenced by professional judgment and payer guidelines. This study used a small load cell (Europa™) at the base of the socket to measure the sagittal moments during walking with three objective categories of prosthetic feet in eleven individuals with transtibial limb loss with MFCL K2, K3 and K4 functional levels. Forefoot stiffness and hysteresis characteristics defined the three foot categories: Stiff, Intermediate, and Compliant. Prosthetic feet were randomly assigned and blinded from participants and investigators. After laboratory testing, participants completed one week community wear tests followed by a modified prosthetics evaluation questionnaire to determine if a specific category of prosthetic feet was preferred. The Compliant category of prosthetic feet was preferred by the participants (P=0.025) over the Stiff and Intermediate prosthetic feet, and the Compliant and Intermediate feet had 15% lower maximum sagittal moments during walking in the laboratory (P=0.0011) compared to the Stiff feet. The activity level of the participants did not change significantly with any of the wear tests in the community, suggesting that each foot was evaluated over a similar number of steps, but did not inherently increase activity. This is the first randomized double blind study in which prosthetic users have expressed a preference for a specific biomechanical characteristic of prosthetic feet: those with lower peak sagittal moments were preferred, and specifically preferred on slopes, stairs, uneven terrain, and during turns and maneuvering during real world use. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Broadband Prosthetic Interfaces: Combining Nerve Transfers and Implantable Multichannel EMG Technology to Decode Spinal Motor Neuron Activity

Directory of Open Access Journals (Sweden)

Konstantin D. Bergmeister

2017-07-01

Full Text Available Modern robotic hands/upper limbs may replace multiple degrees of freedom of extremity function. However, their intuitive use requires a high number of control signals, which current man-machine interfaces do not provide. Here, we discuss a broadband control interface that combines targeted muscle reinnervation, implantable multichannel electromyographic sensors, and advanced decoding to address the increasing capabilities of modern robotic limbs. With targeted muscle reinnervation, nerves that have lost their targets due to an amputation are surgically transferred to residual stump muscles to increase the number of intuitive prosthetic control signals. This surgery re-establishes a nerve-muscle connection that is used for sensing nerve activity with myoelectric interfaces. Moreover, the nerve transfer determines neurophysiological effects, such as muscular hyper-reinnervation and cortical reafferentation that can be exploited by the myoelectric interface. Modern implantable multichannel EMG sensors provide signals from which it is possible to disentangle the behavior of single motor neurons. Recent studies have shown that the neural drive to muscles can be decoded from these signals and thereby the user's intention can be reliably estimated. By combining these concepts in chronic implants and embedded electronics, we believe that it is in principle possible to establish a broadband man-machine interface, with specific applications in prosthesis control. This perspective illustrates this concept, based on combining advanced surgical techniques with recording hardware and processing algorithms. Here we describe the scientific evidence for this concept, current state of investigations, challenges, and alternative approaches to improve current prosthetic interfaces.

Factors Associated with Prosthetic Looseness in Lower Limb Amputees.

Science.gov (United States)

Phonghanyudh, Thong; Sutpasanon, Taweesak; Hathaiareerug, Chanasak; Devakula, M L Buddhibongsa; Kumnerddee, Wipoo

2015-12-01

To determine the factors associated with prosthetic looseness in lower limb amputees in Sisaket province. The present was a cross-sectional descriptive study. Subjects were lower limb amputees who previously obtained prostheses and required prosthetic replacements at the mobile prosthetic laboratory unit under the Prostheses Foundation of H.R.H. the Princess Mother at Khun Han Hospital, Sisaket province, in February 2013. Data including participant characteristics, prosthetic looseness data, and various variables were collected by direct semi-structured interview. Energy expenditures in physical activities were measured using the Thai version of the short format international physical activity questionnaire. Data between participants with and without prosthetic looseness were compared to determine prosthetic loosening associated factors. Among 101 participants enrolled, 33 (32.7%) had prosthetic looseness with average onset of 1.76 ± 1.67 years. Diabetes mellitus was the only significant factor associated with prosthetic looseness from both univariate and multivariate analyses (HR = 7.05, p = 0.002 and HR = 5.93, p = 0.007 respectively). Among the lower limb amputees in Sisaket province, diabetes mellitus was the only factor associated with prosthetic looseness. Therefore, diabetic screening should be supplemented in lower limb amputee assessment protocol. In addition, we recommend that amputees with diabetes mellitus should receive prosthesis check out at approximately

Using computed tomography and 3D printing to construct custom prosthetics attachments and devices.

Science.gov (United States)

Liacouras, Peter C; Sahajwalla, Divya; Beachler, Mark D; Sleeman, Todd; Ho, Vincent B; Lichtenberger, John P

2017-01-01

The prosthetic devices the military uses to restore function and mobility to our wounded warriors are highly advanced, and in many instances not publically available. There is considerable research aimed at this population of young patients who are extremely active and desire to take part in numerous complex activities. While prosthetists design and manufacture numerous devices with standard materials and limb assemblies, patients often require individualized prosthetic design and/or modifications to enable them to participate fully in complex activities. Prosthetists and engineers perform research and implement digitally designs in collaboration to generate equipment for their patient's rehabilitation needs. 3D printing allows for these devices to be manufactured from an array of materials ranging from plastic to titanium alloy. Many designs require form fitting to a prosthetic socket or a complex surface geometry. Specialty items can be scanned using computed tomography and digitally reconstructed to produce a virtual 3D model the engineer can use to design the necessary features of the desired prosthetic, device, or attachment. Completed devices are tested for fit and function. Numerous custom prostheses and attachments have been successfully translated from the research domain to clinical reality, in particular, those that feature the use of computed tomography (CT) reconstructions. The purpose of this project is to describe the research pathways to implementation for the following clinical designs: sets of bilateral hockey skates; custom weightlifting prosthetic hands; and a wine glass holder. This article will demonstrate how to incorporate CT imaging and 3D printing in the design and manufacturing process of custom attachments and assistive technology devices. Even though some of these prosthesis attachments may be relatively simple in design to an engineer, they have an enormous impact on the lives of our wounded warriors.

Natural control capabilities of robotic hands by hand amputated subjects.

Science.gov (United States)

Atzori, Manfredo; Gijsberts, Arjan; Caputo, Barbara; Muller, Henning

2014-01-01

People with transradial hand amputations who own a myoelectric prosthesis currently have some control capabilities via sEMG. However, the control systems are still limited and not natural. The Ninapro project is aiming at helping the scientific community to overcome these limits through the creation of publicly available electromyography data sources to develop and test machine learning algorithms. In this paper we describe the movement classification results gained from three subjects with an homogeneous level of amputation, and we compare them with the results of 40 intact subjects. The number of considered subjects can seem small at first sight, but it is not considering the literature of the field (which has to face the difficulty of recruiting trans-radial hand amputated subjects). The classification is performed with four different classifiers and the obtained balanced classification rates are up to 58.6% on 50 movements, which is an excellent result compared to the current literature. Successively, for each subject we find a subset of up to 9 highly independent movements, (defined as movements that can be distinguished with more than 90% accuracy), which is a deeply innovative step in literature. The natural control of a robotic hand in so many movements could lead to an immediate progress in robotic hand prosthetics and it could deeply change the quality of life of amputated subjects.

Vascular complications of prosthetic inter-vertebral discs

OpenAIRE

Daly, Kevin J.; Ross, E. Raymond S.; Norris, Heather; McCollum, Charles N.

2006-01-01

Five consecutive cases of prosthetic inter-vertebral disc displacement with severe vascular complications on revisional surgery are described. The objective of this case report is to warn spinal surgeons that major vascular complications are likely with anterior displacement of inter-vertebral discs. We have not been able to find a previous report on vascular complications associated with anterior displacement of prosthetic inter-vertebral discs. In all five patients the prosthetic disc had e...

Advanced Prosthetic Gait Training Tool

Science.gov (United States)

2015-12-01

modules to train individuals to distinguish gait deviations (trunk motion and lower-limb motion). Each of these modules help trainers improve their...AWARD NUMBER: W81XWH-10-1-0870 TITLE: Advanced Prosthetic Gait Training Tool PRINCIPAL INVESTIGATOR: Dr. Karim Abdel-Malek CONTRACTING...study is to produce a computer-based Advanced Prosthetic Gait Training Tool to aid in the training of clinicians at military treatment facilities

Prosthetic Engineering

Science.gov (United States)

... the household and community environments may lead to falls and injuries. This research aims to develop an ankle that can invert and evert and thereby control the center of pressure under the prosthetic foot; enhancing balance and stability of lower limb amputees. Foot-Ankle ...

Second-site prosthetic joint infection in patients with multiple prosthetic joints.

Science.gov (United States)

Clesham, Kevin; Hughes, Andrew J; O' hEireamhoin, Sven; Fleming, Catherine; Murphy, Colin G

2018-04-10

Prosthetic joint infections (PJIs) are among the most serious complications in arthroplasty. A second-site PJI in patients with multiple prosthetic joints increases morbidity, with many requiring further revision procedures. We aimed to establish why some patients with multiple joints develop second-site infections. Our institution's arthroplasty database was reviewed from 2004 to 2017. All PJIs were identified, and all patients with more than one prosthetic joint in situ were included. We recorded risk factors, causative organisms, number of procedures and length of stay. Forty-four patients meeting the criteria were identified. Four patients (9.1%) developed second-site infection. Eight patients (18.2%) developed re-infection of the primary PJI. Positive MRSA carrier status and PJI of a total knee replacement were associated with an increased risk of a second episode of infection. Patients who developed further infection had more frequent admission and longer lengths of stay than isolated PJIs. Higher morbidity and use of hospital resources are associated with this cohort of patients. PJIs in total knee replacements and positive MRSA status are associated with higher rates of second infection. Identifying this vulnerable cohort of patients at an early stage is critical to ensure measures are taken to reduce the risks of further infection.

Prosthetics / Limb Loss

Science.gov (United States)

... implant to encourage the sealing process. Implanting titanium prosthetic components avoids the need for a socket. But preventing bacterial invasion and infection is a key challenge, one that this research ...

Review of Prosthetic Joint Infection from Listeria monocytogenes.

Science.gov (United States)

Bader, Gilbert; Al-Tarawneh, Mohammed; Myers, James

2016-12-01

Prosthetic joint infection from Listeria monocytogenes is rare. We decided to shed light on this illness and review the reported cases to better understand its characteristics. We conducted a comprehensive review of the English literature using PubMed. We also included one case that we had managed. We found 25 cases of prosthetic joint infection from L. monocytogenes reported individually and a retrospective study of 43 cases of joint and bone listerial infection, including 34 with prosthetic joint infection, conducted in France. We have described their clinical and para-clinical features and tried to elaborate on the pathophysiology, treatment, and prevention. Prosthetic joint infection from L. monocytogenes is mainly late. Systemic inflammation may be absent. Although rare, it must be suspected in patients at high risk for both prosthetic joint and listerial infections. In addition, those patients must be instructed on appropriate preventive measures.

Pannus-related prosthetic valve dysfunction. Case report.

Science.gov (United States)

Moldovan, Maria-Sînziana; Bedeleanu, Daniela; Kovacs, Emese; Ciumărnean, Lorena; Molnar, Adrian

2016-01-01

Pannus-related prosthetic valve dysfunction, a complication of mechanical prosthetic valve replacement, is rare, with a slowly progressive evolution, but it can be acute, severe, requiring surgical reintervention. We present the case of a patient with a mechanical single disc aortic prosthesis, with moderate prosthesis-patient mismatch, minor pannus found on previous ultrasound examinations, who presented to our service with angina pain with a duration of 1 hour, subsequently interpreted as non-ST segment elevation myocardial infarction (NSTEMI) syndrome. Coronarography showed normal epicardial coronary arteries, an ample movement of the prosthetic disc, without evidence of coronary thromboembolism, and Gated Single-Photon Emission Computerized Tomography (SPECT) with Technetium (Tc)-99m detected no perfusion defects. Transthoracic echocardiography (TTE) evidenced a dysfunctional prosthesis due to a subvalvular mass; transesophageal echocardiography (TOE) showed the interference of this mass, with a pannus appearance, with the closure of the prosthetic disc. Under conditions of repeated angina episodes, under anticoagulant treatment, surgery was performed, with the intraoperative confirmation of pannus and its removal. Postoperative evolution was favorable. This case reflects the diagnostic and therapeutic management problems of pannus-related prosthetic valve dysfunction.

Enhanced ultrasound for advanced diagnostics, ultrasound tomography for volume limb imaging and prosthetic fitting

Science.gov (United States)

Anthony, Brian W.

2016-04-01

Ultrasound imaging methods hold the potential to deliver low-cost, high-resolution, operator-independent and nonionizing imaging systems - such systems couple appropriate algorithms with imaging devices and techniques. The increasing demands on general practitioners motivate us to develop more usable and productive diagnostic imaging equipment. Ultrasound, specifically freehand ultrasound, is a low cost and safe medical imaging technique. It doesn't expose a patient to ionizing radiation. Its safety and versatility make it very well suited for the increasing demands on general practitioners, or for providing improved medical care in rural regions or the developing world. However it typically suffers from sonographer variability; we will discuss techniques to address user variability. We also discuss our work to combine cylindrical scanning systems with state of the art inversion algorithms to deliver ultrasound systems for imaging and quantifying limbs in 3-D in vivo. Such systems have the potential to track the progression of limb health at a low cost and without radiation exposure, as well as, improve prosthetic socket fitting. Current methods of prosthetic socket fabrication remain subjective and ineffective at creating an interface to the human body that is both comfortable and functional. Though there has been recent success using methods like magnetic resonance imaging and biomechanical modeling, a low-cost, streamlined, and quantitative process for prosthetic cup design and fabrication has not been fully demonstrated. Medical ultrasonography may inform the design process of prosthetic sockets in a more objective manner. This keynote talk presents the results of progress in this area.

Validation of the prosthetic esthetic index

DEFF Research Database (Denmark)

Özhayat, Esben B; Dannemand, Katrine

2014-01-01

OBJECTIVES: In order to diagnose impaired esthetics and evaluate treatments for these, it is crucial to evaluate all aspects of oral and prosthetic esthetics. No professionally administered index currently exists that sufficiently encompasses comprehensive prosthetic esthetics. This study aimed...... to validate a new comprehensive index, the Prosthetic Esthetic Index (PEI), for professional evaluation of esthetics in prosthodontic patients. MATERIAL AND METHODS: The content, criterion, and construct validity; the test-retest, inter-rater, and internal consistency reliability; and the sensitivity...... furthermore distinguish between participants and controls, indicating sufficient sensitivity. CONCLUSION: The PEI is considered a valid and reliable instrument involving sufficient aspects for assessment of the professionally evaluated esthetics in prosthodontic patients. CLINICAL RELEVANCE...

Locomotor Performance During Rehabilitation of People With Lower Limb Amputation and Prosthetic Nonuse 12 Months After Discharge.

Science.gov (United States)

Roffman, Caroline E; Buchanan, John; Allison, Garry T

2016-07-01

It is recognized that multifactorial assessments are needed to evaluate balance and locomotor function in people with lower limb amputation. There is no consensus on whether a single screening tool could be used to identify future issues with locomotion or prosthetic use. The purpose of this study was to determine whether different tests of locomotor performance during rehabilitation were associated with significantly greater risk of prosthetic abandonment at 12 months postdischarge. This was a retrospective cohort study. Data for descriptive variables and locomotor tests (ie, 10-Meter Walk Test [10MWT], Timed "Up & Go" Test [TUGT], Six-Minute Walk Test [6MWT], and Four Square Step Test [FSST]) were abstracted from the medical records of 201 consecutive participants with lower limb amputation. Participants were interviewed and classified as prosthetic users or nonusers at 12 months postdischarge. The Mann-Whitney U test was used to analyze whether there were differences in locomotor performance. Receiver operating characteristic curves were generated to determine performance thresholds, and relative risk (RR) was calculated for nonuse. At 12 months postdischarge, 18% (n=36) of the participants had become prosthetic nonusers. Performance thresholds, area under the curve (AUC), and RR of nonuse (95% confidence intervals [CI]) were: for the 10MWT, if walking speed was ≤0.44 ms(-1) (AUC=0.743), RR of nonuse=2.76 (95% CI=1.83, 3.79; PLocomotor performance during rehabilitation may predict future risk of prosthetic nonuse. It may be implied that the 10MWT has the greatest clinical utility as a single screening tool for prosthetic nonuse, given the highest proportion of participants were able to perform this test early in rehabilitation. However, as locomotor skills improve, other tests (in particular, the 6MWT) have specific clinical utility. To fully enable implementation of these locomotor criteria for prosthetic nonuse into clinical practice, validation is warranted

Candida infection of a prosthetic shoulder joint

Energy Technology Data Exchange (ETDEWEB)

Lichtman, E.A.

1983-09-01

A heroin addict developed a Candida parapsilosis infection in a prosthetic shoulder joint. Radiographs showed loose fragments of cement with prosthetic loosening. The patient was treated with removal of the prosthesis and intravenous amphotericin B followed by oral ketoconazole.

Candida infection of a prosthetic shoulder joint

International Nuclear Information System (INIS)

Lichtman, E.A.; Veterans Administration Medical Center, New York

1983-01-01

A heroin addict developed a Candida parapsilosis infection in a prosthetic shoulder joint. Radiographs showed loose fragments of cement with prosthetic loosening. The patient was treated with removal of the prosthesis and intravenous amphotericin B followed by oral ketoconazole. (orig.)

Management of Prosthetic Joint Infection.

Science.gov (United States)

Tande, Aaron J; Gomez-Urena, Eric O; Berbari, Elie F; Osmon, Douglas R

2017-06-01

Although uncommon, prosthetic joint infection is a devastating complication. This challenging condition requires a coordinated management approach to achieve good patient outcomes. This review details the general principles to consider when managing patients with prosthetic joint infection. The different medical/surgical treatment strategies and how to appropriately select a strategy are discussed. The data to support each strategy are presented, along with discussion of antimicrobial strategies in specific situations. Copyright © 2017 Elsevier Inc. All rights reserved.

Which prosthetic foot to prescribe?

OpenAIRE

De Asha, AR; Barnett, CT; Struchkov, V; Buckley, JG

2017-01-01

Introduction: \\ud Clinicians typically use findings from cohort studies to objectively inform judgements regarding the potential (dis)advantages of prescribing a new prosthetic device. However, before finalising prescription a clinician will typically ask a patient to 'try out' a change of prosthetic device while the patient is at the clinic. Observed differences in gait when using the new device should be the result of the device’s mechanical function, but could also conceivably be due to pa...

Analysis of Interrelationships among Voluntary and Prosthetic Leg Joint Parameters Using Cyclograms.

Science.gov (United States)

Jasni, Farahiyah; Hamzaid, Nur Azah; Mohd Syah, Nor Elleeiana; Chung, Tze Y; Abu Osman, Noor Azuan

2017-01-01

The walking mechanism of a prosthetic leg user is a tightly coordinated movement of several joints and limb segments. The interaction among the voluntary and mechanical joints and segments requires particular biomechanical insight. This study aims to analyze the inter-relationship between amputees' voluntary and mechanical coupled leg joints variables using cyclograms. From this analysis, the critical gait parameters in each gait phase were determined and analyzed if they contribute to a better powered prosthetic knee control design. To develop the cyclogram model, 20 healthy able-bodied subjects and 25 prosthesis and orthosis users (10 transtibial amputees, 5 transfemoral amputees, and 10 different pathological profiles of orthosis users) walked at their comfortable speed in a 3D motion analysis lab setting. The gait parameters (i.e., angle, moment and power for the ankle, knee and hip joints) were coupled to form 36 cyclograms relationship. The model was validated by quantifying the gait disparities of all the pathological walking by analyzing each cyclograms pairs using feed-forward neural network with backpropagation. Subsequently, the cyclogram pairs that contributed to the highest gait disparity of each gait phase were manipulated by replacing it with normal values and re-analyzed. The manipulated cyclograms relationship that showed highest improvement in terms of gait disparity calculation suggested that they are the most dominant parameters in powered-knee control. In case of transfemoral amputee walking, it was identified using this approach that at each gait sub-phase, the knee variables most responsible for closest to normal walking were: knee power during loading response and mid-stance, knee moment and knee angle during terminal stance phase, knee angle and knee power during pre-swing, knee angle at initial swing, and knee power at terminal swing. No variable was dominant during mid-swing phase implying natural pendulum effect of the lower limb between

Analysis of Interrelationships among Voluntary and Prosthetic Leg Joint Parameters Using Cyclograms

Directory of Open Access Journals (Sweden)

Nur Azah Hamzaid

2017-04-01

Full Text Available The walking mechanism of a prosthetic leg user is a tightly coordinated movement of several joints and limb segments. The interaction among the voluntary and mechanical joints and segments requires particular biomechanical insight. This study aims to analyze the inter-relationship between amputees' voluntary and mechanical coupled leg joints variables using cyclograms. From this analysis, the critical gait parameters in each gait phase were determined and analyzed if they contribute to a better powered prosthetic knee control design. To develop the cyclogram model, 20 healthy able-bodied subjects and 25 prosthesis and orthosis users (10 transtibial amputees, 5 transfemoral amputees, and 10 different pathological profiles of orthosis users walked at their comfortable speed in a 3D motion analysis lab setting. The gait parameters (i.e., angle, moment and power for the ankle, knee and hip joints were coupled to form 36 cyclograms relationship. The model was validated by quantifying the gait disparities of all the pathological walking by analyzing each cyclograms pairs using feed-forward neural network with backpropagation. Subsequently, the cyclogram pairs that contributed to the highest gait disparity of each gait phase were manipulated by replacing it with normal values and re-analyzed. The manipulated cyclograms relationship that showed highest improvement in terms of gait disparity calculation suggested that they are the most dominant parameters in powered-knee control. In case of transfemoral amputee walking, it was identified using this approach that at each gait sub-phase, the knee variables most responsible for closest to normal walking were: knee power during loading response and mid-stance, knee moment and knee angle during terminal stance phase, knee angle and knee power during pre-swing, knee angle at initial swing, and knee power at terminal swing. No variable was dominant during mid-swing phase implying natural pendulum effect of the

Bruxism and prosthetic treatment: a critical review.

Science.gov (United States)

Johansson, Anders; Omar, Ridwaan; Carlsson, Gunnar E

2011-07-01

Based on the findings from available research on bruxism and prosthetic treatment published in the dental literature, an attempt was made to draw conclusions about the existence of a possible relationship between the two, and its clinical relevance. MEDLINE/PubMed searches were conducted using the terms 'bruxism' and 'prosthetic treatment', as well as combinations of these and related terms. The few studies judged to be relevant were critically reviewed, in addition to papers found during an additional manual search of reference lists within selected articles. Bruxism is a common parafunctional habit, occurring both during sleep and wakefulness. Usually it causes few serious effects, but can do so in some patients. The etiology is multifactorial. There is no known treatment to stop bruxism, including prosthetic treatment. The role of bruxism in the process of tooth wear is unclear, but it is not considered a major cause. As informed by the present critical review, the relationship between bruxism and prosthetic treatment is one that relates mainly to the effect of the former on the latter. Bruxism may be included among the risk factors, and is associated with increased mechanical and/or technical complications in prosthodontic rehabilitation, although it seems not to affect implant survival. When prosthetic intervention is indicated in a patient with bruxism, efforts should be made to reduce the effects of likely heavy occlusal loading on all the components that contribute to prosthetic structural integrity. Failure to do so may indicate earlier failure than is the norm. Copyright © 2011 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Graft-Sparing Strategy for Thoracic Prosthetic Graft Infection.

Science.gov (United States)

Uchino, Gaku; Yoshida, Takeshi; Kakii, Bunpachi; Furui, Masato

2018-04-01

 Thoracic prosthetic graft infection is a rare but serious complication with no standard management. We reported our surgical experience on graft-sparing strategy for thoracic prosthetic graft infection.  This study included patients who underwent graft-sparing surgery for thoracic prosthetic graft infection at Matsubara Tokushukai Hospital in Japan from January 2000 to October 2017.  There were 17 patients included in the analyses, with a mean age at surgery of 71.0 ± 10.5 years; 11 were men. In-hospital mortality was observed in five patients (29.4%).  Graft-sparing surgery for thoracic prosthetic graft infection is an alternative option particularly for early graft infection after hemiarch replacement. Georg Thieme Verlag KG Stuttgart · New York.

Echocardiographic evaluation of heart valve prosthetic dysfunction

Directory of Open Access Journals (Sweden)

Yuriy Ivaniv

2018-02-01

Full Text Available Patients with replaced heart valve submitted to echocardiographic examination may have symptoms related either to valvular malfunction or ventricular dysfunction from different causes. Clinical examination is not reliable in a prosthetic valve evaluation and the main information regarding its function could be obtained using different cardiac ultrasound modalities. This review provides a description of echocardiographic and Doppler techniques useful in evaluation of prosthetic heart valves. For the interpretation of echocardiography there is a need in special knowledge of prosthesis types and possible reasons of prosthetic function deterioration. Echocardiography allows to reveal valve thrombosis, pannus formation, vegetation and such complications of infective endocarditis as valve ring abscess or dehiscence. Transthoracic echocardiography requires different section plane angles and unconventional views. Transesophageal echocardiography is more often used than in native valve examination due to better visualization of prosthetic valve structure and function. Three-dimensional echocardiography could provide more detailed visual information especially in the assessment of paravalvular regurgitation or valve obstruction.

Prosthetic management of deciduous teeth

OpenAIRE

Bassil, Jean

2015-01-01

Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária Introduction: Situations of single or multiple edentulous are not an exception during childhood. Prosthetic management is necessary in case of absence of replacing tooth or when its eruption is planned too far in time. Indications of prosthetic rehabilitation for children are multiple and rise from the etiologic factors caus...

100 top-cited scientific papers in limb prosthetics.

Science.gov (United States)

Eshraghi, Arezoo; Osman, Noor Azuan Abu; Gholizadeh, Hossein; Ali, Sadeeq; Shadgan, Babak

2013-11-17

Research has tremendously contributed to the developments in both practical and fundamental aspects of limb prosthetics. These advancements are reflected in scientific articles, particularly in the most cited papers. This article aimed to identify the 100 top-cited articles in the field of limb prosthetics and to investigate their main characteristics. Articles related to the field of limb prosthetics and published in the Web of Knowledge database of the Institute for Scientific Information (ISI) from the period of 1980 to 2012. The 100 most cited articles in limb prosthetics were selected based on the citation index report. All types of articles except for proceedings and letters were included in the study. The study design and level of evidence were determined using Sackett's initial rules of evidence. The level of evidence was categorized either as a systematic review or meta-analysis, randomized controlled trial, cohort study, case-control study, case series, expert opinion, or design and development. The top cited articles in prosthetics were published from 1980 to 2012 with a citation range of 11 to 90 times since publication. The mean citation rate was 24.43 (SD 16.7) times. Eighty-four percent of the articles were original publications and were most commonly prospective (76%) and case series studies (67%) that used human subjects (96%) providing level 4 evidence. Among the various fields, rehabilitation (47%), orthopedics (29%), and sport sciences (28%) were the most common fields of study. The study established that studies conducted in North America and were written in English had the highest citations. Top cited articles primarily dealt with lower limb prosthetics, specifically, on transtibial and transradial prosthetic limbs. Majority of the articles were experimental studies.

Responsiveness of the Prosthetic Esthetic Scale

DEFF Research Database (Denmark)

Øzhayat, Esben Boeskov

2017-01-01

Objectives The aim of the study was to evaluate the responsiveness of the Prosthetic Esthetic Index (PEI) in a population who received prosthetic replacements. Materials and methods Fifty-seven patients who received prosthetic replacement of at least one tooth by means of fixed or removable...... prosthesis were professionally esthetically evaluated using the PEI and the Dental Aesthetic Index (DAI) before and after treatment. The participants further evaluated their oral esthetics using the Oral Health Impact Profile Aesthetic (OHIP-Aes) and Orofacial Esthetic Index (OES). Responsiveness......-Aes and OES scores. The PEI was more consistent in responsiveness than the DAI. Conclusions The PEI shows sufficient responsiveness for use in longitudinal studies and for use as a follow-up measure in clinical practice. Clinical relevance The PEI can in a standardized manner monitor and document esthetic...

Stiffness and hysteresis properties of some prosthetic feet

OpenAIRE

van Jaarsveld, H.W.L.; Grootenboer, H.J.; de Vries, J.; Koopman, Hubertus F.J.M.

1990-01-01

A prosthetic foot is an important element of a prosthesis, although it is not always fully recognized that the properties of the foot, along with the prosthetic knee joint and the socket, are in part responsible for the stability and metabolic energy cost during walking. The stiffness and the hysteresis, which are the topics of this paper, are not properly prescribed, but could be adapted to improve the prosthetic walking performance. The shape is strongly related to the cosmetic appearance a...

Parietal neural prosthetic control of a computer cursor in a graphical-user-interface task

Science.gov (United States)

Revechkis, Boris; Aflalo, Tyson NS; Kellis, Spencer; Pouratian, Nader; Andersen, Richard A.

2014-12-01

Objective. To date, the majority of Brain-Machine Interfaces have been used to perform simple tasks with sequences of individual targets in otherwise blank environments. In this study we developed a more practical and clinically relevant task that approximated modern computers and graphical user interfaces (GUIs). This task could be problematic given the known sensitivity of areas typically used for BMIs to visual stimuli, eye movements, decision-making, and attentional control. Consequently, we sought to assess the effect of a complex, GUI-like task on the quality of neural decoding. Approach. A male rhesus macaque monkey was implanted with two 96-channel electrode arrays in area 5d of the superior parietal lobule. The animal was trained to perform a GUI-like ‘Face in a Crowd’ task on a computer screen that required selecting one cued, icon-like, face image from a group of alternatives (the ‘Crowd’) using a neurally controlled cursor. We assessed whether the crowd affected decodes of intended cursor movements by comparing it to a ‘Crowd Off’ condition in which only the matching target appeared without alternatives. We also examined if training a neural decoder with the Crowd On rather than Off had any effect on subsequent decode quality. Main results. Despite the additional demands of working with the Crowd On, the animal was able to robustly perform the task under Brain Control. The presence of the crowd did not itself affect decode quality. Training the decoder with the Crowd On relative to Off had no negative influence on subsequent decoding performance. Additionally, the subject was able to gaze around freely without influencing cursor position. Significance. Our results demonstrate that area 5d recordings can be used for decoding in a complex, GUI-like task with free gaze. Thus, this area is a promising source of signals for neural prosthetics that utilize computing devices with GUI interfaces, e.g. personal computers, mobile devices, and tablet

Parietal neural prosthetic control of a computer cursor in a graphical-user-interface task.

Science.gov (United States)

Revechkis, Boris; Aflalo, Tyson N S; Kellis, Spencer; Pouratian, Nader; Andersen, Richard A

2014-12-01

To date, the majority of Brain-Machine Interfaces have been used to perform simple tasks with sequences of individual targets in otherwise blank environments. In this study we developed a more practical and clinically relevant task that approximated modern computers and graphical user interfaces (GUIs). This task could be problematic given the known sensitivity of areas typically used for BMIs to visual stimuli, eye movements, decision-making, and attentional control. Consequently, we sought to assess the effect of a complex, GUI-like task on the quality of neural decoding. A male rhesus macaque monkey was implanted with two 96-channel electrode arrays in area 5d of the superior parietal lobule. The animal was trained to perform a GUI-like 'Face in a Crowd' task on a computer screen that required selecting one cued, icon-like, face image from a group of alternatives (the 'Crowd') using a neurally controlled cursor. We assessed whether the crowd affected decodes of intended cursor movements by comparing it to a 'Crowd Off' condition in which only the matching target appeared without alternatives. We also examined if training a neural decoder with the Crowd On rather than Off had any effect on subsequent decode quality. Despite the additional demands of working with the Crowd On, the animal was able to robustly perform the task under Brain Control. The presence of the crowd did not itself affect decode quality. Training the decoder with the Crowd On relative to Off had no negative influence on subsequent decoding performance. Additionally, the subject was able to gaze around freely without influencing cursor position. Our results demonstrate that area 5d recordings can be used for decoding in a complex, GUI-like task with free gaze. Thus, this area is a promising source of signals for neural prosthetics that utilize computing devices with GUI interfaces, e.g. personal computers, mobile devices, and tablet computers.

Consumer design priorities for upper limb prosthetics.

Science.gov (United States)

Biddiss, Elaine; Beaton, Dorcas; Chau, Tom

2007-11-01

To measure consumer satisfaction with upper limb prosthetics and provide an enumerated list of design priorities for future developments. A self-administered, anonymous survey collected information on participant demographics, history of and goals for prosthesis use, satisfaction, and design priorities. The questionnaire was available online and in paper format and was distributed through healthcare providers, community support groups, and one prosthesis manufacturer; 242 participants of all ages and levels of upper limb absence completed the survey. Rates of rejection for myoelectric hands, passive hands, and body-powered hooks were 39%, 53%, and 50%, respectively. Prosthesis wearers were generally satisfied with their devices while prosthesis rejecters were dissatisfied. Reduced prosthesis weight emerged as the highest priority design concern of consumers. Lower cost ranked within the top five design priorities for adult wearers of all device types. Life-like appearance is a priority for passive/cosmetic prostheses, while improved harness comfort, wrist movement, grip control and strength are required for body-powered devices. Glove durability, lack of sensory feedback, and poor dexterity were also identified as design priorities for electric devices. Design priorities reflect consumer goals for prosthesis use and vary depending on the type of prosthesis used and age. Future design efforts should focus on the development of more light-weight, comfortable prostheses.

Control method for prosthetic devices

Science.gov (United States)

Bozeman, Richard J., Jr. (Inventor)

1995-01-01

A control system and method for prosthetic devices is provided. The control system comprises a transducer for receiving movement from a body part for generating a sensing signal associated with that movement. The sensing signal is processed by a linearizer for linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part. The linearized sensing signal is normalized to be a function of the entire range of body part movement from the no-shrug position of the moveable body part. The normalized signal is divided into a plurality of discrete command signals. The discrete command signals are used by typical converter devices which are in operational association with the prosthetic device. The converter device uses the discrete command signals for driving the moveable portions of the prosthetic device and its sub-prosthesis. The method for controlling a prosthetic device associated with the present invention comprises the steps of receiving the movement from the body part, generating a sensing signal in association with the movement of the body part, linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part, normalizing the linear signal to be a function of the entire range of the body part movement, dividing the normalized signal into a plurality of discrete command signals, and implementing the plurality of discrete command signals for driving the respective moveable prosthesis device and its sub-prosthesis.

Tomographic and echocardiographic diagnosis of mitral prosthetic valve thrombosis

International Nuclear Information System (INIS)

Sainz Gonzalez de la Penna, Benito; Ramos Gutierrez, Luis Benito; Gonzalez Artiles, Iovank

2010-01-01

Despite the progress achieved in the design of mechanical prosthetic valves, prosthetic valve thrombosis remains a frequent cause of morbidity, usually due to incorrect anticoagulation. A patient was presented with mitral prosthetic thrombosis one year after implantation, who had been diagnosed by transthoracic transesophageal echocardiography imaging and 64-slice computed tomography. Thrombolytic therapy was successful and led to the satisfactory evolution of the patient

PEMODELAN PERSAMAAN NEWTON-EULER PADA PENGEMBANGAN PROSTHETIC TANGAN KOSMETIK DALAM MENENTUKAN BESARNYA DAYA PADA SISTEM KABEL EXTERNAL

Directory of Open Access Journals (Sweden)

Lobes Herdiman

2012-01-01

sebesar 12,5041 watt. Daya yang dihasilkan dapat digunakan sebagai dasar menentukan spesifikasi motor. Spesifikasi motor yaitu tipe motor servo dengan seri PTSV4835 atau SV4835, rpm 55,1, volt (12,13 V, I (4.27 amp, input (51,82 watt, torque ( 47 kg-cm, output (26,60 watt dan efficiency sebesar 51,33%. Kata kunci: Prosthetic tangan kosmetik, functional requirements, 6 model gerakan dasar, Newton Euler, tosi, daya Abstract   Development of Prosthetic hand component consists of the metacarpal, metacarpal pollicis, and fingers. The material used is nylon, the number of components of 87 and 175 grams weight. Ability thumb and index finger an important role in the movement to 6 models. The position of the tip-media Phalanx distalis thumb and index finger meet at one point, so that they can perform the basic hand movements. Testing with empirical experiments on the development of cosmetics Prosthetic hand performed to determine the rotation of the coordinate points on the joints during activities of holdings. Coordinate axis and space axis system where x, y, and z, with zero point set at the base of the main shaft. Model mechanism cosmetics Prosthetic hand with withdrawal system to control an external cable. Measurement of pressure on the thumb with the index finger of 493 grams which is done by means of a dial indicator, measuring the pressure with the thumb middle finger for 487 grams. Load Testing pull cable to open the fingers to be fully open by 4291 grams with a force gauge. Newton-Euler equations to produce the amount of torque through the equation forward (forward and backward (backward. Rotation matrix symbolized xRx +1, with x is the starting point and x +1 is the destination point. Point coordinates on each segment as a degree of freedom on three points, namely the point 0, point 1 and point 2. Rotation matrix calculation using the starting point (origin and the destination point (destination. Fingers 0 points specified in the metacarpophalangeal joints, point 1 on

Prosthetic Consideration in Implant-supported Prosthesis: A Review of Literature.

Science.gov (United States)

Gowd, Manga Snigdha; Shankar, Thatapudi; Ranjan, Rajeev; Singh, Arpita

2017-06-01

Modern dentistry has changed tremendously with implant therapy. For the successful implant therapy, making a proper treatment plan considering both surgical and prosthetic part in mind is the key of success. Often practitioners tend to create a treatment plan overlooking the basic principles of prosthetic part. This present review has discussed various prosthetic consideration of implant-supported prosthesis. A step-by-step detailed prosthetic option with their indications has been discussed to help all dental implant practitioners in making of an optimal treatment plan for each case.

The role of vision processing in prosthetic vision.

Science.gov (United States)

Barnes, Nick; He, Xuming; McCarthy, Chris; Horne, Lachlan; Kim, Junae; Scott, Adele; Lieby, Paulette

2012-01-01

Prosthetic vision provides vision which is reduced in resolution and dynamic range compared to normal human vision. This comes about both due to residual damage to the visual system from the condition that caused vision loss, and due to limitations of current technology. However, even with limitations, prosthetic vision may still be able to support functional performance which is sufficient for tasks which are key to restoring independent living and quality of life. Here vision processing can play a key role, ensuring that information which is critical to the performance of key tasks is available within the capability of the available prosthetic vision. In this paper, we frame vision processing for prosthetic vision, highlight some key areas which present problems in terms of quality of life, and present examples where vision processing can help achieve better outcomes.

Antithrombotic Therapy in Patients with Prosthetic Heart Valves

Directory of Open Access Journals (Sweden)

Mohamed HA

2009-01-01

Full Text Available Patients with mechanical valve prostheses require a lifelong anticoagulant treatment. The combined use of Warfarin and low-dose aspirin appears to reduce the risk of valve thrombosis and systemic embolism at a low risk of bleeding. The management of women with prosthetic heart valves during pregnancy poses a particular challenge, as there are no available controlled clinical trials to provide guidelines for effective antithrombotic therapy. Oral anticoagulants, such as Warfarin, cause foetal embryopathy; unfractionated heparin and low-molecular-weight heparin have been reported to be ineffective in preventing thromboembolic complications.This article discusses the available data and the most recent guidelines in the antithrombotic management of patients with prosthetic valves, and antithrombotic therapy in various clinical situations such as pregnant women with prosthetic heart valves, and patients with prosthetic heart valves undergoing noncardiac surgery.

Electromyography data for non-invasive naturally-controlled robotic hand prostheses.

Science.gov (United States)

Atzori, Manfredo; Gijsberts, Arjan; Castellini, Claudio; Caputo, Barbara; Hager, Anne-Gabrielle Mittaz; Elsig, Simone; Giatsidis, Giorgio; Bassetto, Franco; Müller, Henning

2014-01-01

Recent advances in rehabilitation robotics suggest that it may be possible for hand-amputated subjects to recover at least a significant part of the lost hand functionality. The control of robotic prosthetic hands using non-invasive techniques is still a challenge in real life: myoelectric prostheses give limited control capabilities, the control is often unnatural and must be learned through long training times. Meanwhile, scientific literature results are promising but they are still far from fulfilling real-life needs. This work aims to close this gap by allowing worldwide research groups to develop and test movement recognition and force control algorithms on a benchmark scientific database. The database is targeted at studying the relationship between surface electromyography, hand kinematics and hand forces, with the final goal of developing non-invasive, naturally controlled, robotic hand prostheses. The validation section verifies that the data are similar to data acquired in real-life conditions, and that recognition of different hand tasks by applying state-of-the-art signal features and machine-learning algorithms is possible.

38 CFR 17.150 - Prosthetic and similar appliances.

Science.gov (United States)

2010-07-01

... appliances. 17.150 Section 17.150 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS MEDICAL Prosthetic, Sensory, and Rehabilitative Aids § 17.150 Prosthetic and similar appliances... appliances including invalid lifts and therapeutic and rehabilitative devices, and special clothing made...

Pre-prosthetic surgical alterations in maxillectomy to enhance the prosthetic prognoses as part of rehabilitation of oral cancer patient.

Science.gov (United States)

El Fattah, H; Zaghloul, A; Pedemonte, E; Escuin, T

2012-03-01

After maxillectomy, prosthetic restoration of the resulting defect is an essential step because it signals the beginning of patient's rehabilitation. The obturator used to restore the defect should be comfortable, restore adequate speech, deglutition, mastication, and be cosmetically acceptable, success will depend on the size and location of the defect and the quantity and integrity of the remaining structures, in addition to pre-prosthetic surgical preparation of defect site. Preoperative cooperation between the oncologist surgeon and the maxillofacial surgeon may allow obturation of a resultant defect by preservation of the premaxilla or the tuberosity on the defect side and maintaining the alveolar bone or teeth adjacent to the defect. This study evaluates the importance of pre-prosthetic surgical alterations at the time maxillectomy on the enhancement of the prosthetic prognoses as part of the rehabilitation of oral cancer patient. The study was carried out between 2003- 2008, on 66 cancer patients(41 male-25 female) age ranged from 33 to 72 years, at National Cancer Institute, Cairo University, whom underwent maxillectomy surgery to remove malignant tumor as a part of cancer treatment. Patients were divided in two groups. Group A: Resection of maxilla followed by preprosthetic surgical preparation. Twenty-four cancer patients (13 male - 11 female). Group B: Resection of maxilla without any preprosthetic surgical preparation. Forty-two cancer patients (28 male-14 female). Outcome variables measured included facial contour and aesthetic results, speech understandability, ability to eat solid foods, oronasal separation, socializing outside the home, and return-to-work status. Flap success and donor site morbidity were also studied. To improve the prosthetic restoration of maxillary defect resulting maxillary resection as part treatment of maxillofacial tumor depends on the close cooperation between prosthodontist and surgeon, by combination of pre-prosthetic

Rotationplasty with vascular reconstruction for prosthetic knee joint infection.

Science.gov (United States)

Fujiki, Masahide; Miyamoto, Shimpei; Nakatani, Fumihiko; Kawai, Akira; Sakuraba, Minoru

2015-01-01

Rotationplasty is used most often as a function-preserving salvage procedure after resection of sarcomas of the lower extremity; however, it is also used after infection of prosthetic knee joints. Conventional vascular management during rotationplasty is to preserve and coil major vessels, but recently, transection and reanastomosis of the major vessels has been widely performed. However, there has been little discussion regarding the optimal vascular management of rotationplasty after infection of prosthetic knee joints because rotationplasty is rarely performed for this indication. We reviewed four patients who had undergone resection of osteosarcomas of the femur, placement of a prosthetic knee joint, and rotationplasty with vascular reconstruction from 2010 to 2013. The mean interval between prosthetic joint replacement and rotationplasty was 10.4 years and the mean interval between the diagnosis of prosthesis infection and rotationplasty was 7.9 years. Rotationplasty was successful in all patients; however, in one patient, arterial thrombosis developed and necessitated urgent surgical removal and arterial reconstruction. All patients were able to walk independently with a prosthetic limb after rehabilitation. Although there is no consensus regarding the most appropriate method of vascular management during rotationplasty for revision of infected prosthetic joints, vascular transection and reanastomosis is a useful option.

Control System for Prosthetic Devices

Science.gov (United States)

Bozeman, Richard J. (Inventor)

1996-01-01

A control system and method for prosthetic devices is provided. The control system comprises a transducer for receiving movement from a body part for generating a sensing signal associated with that of movement. The sensing signal is processed by a linearizer for linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part. The linearized sensing signal is normalized to be a function of the entire range of body part movement from the no-shrug position of the moveable body part through the full-shrg position of the moveable body part. The normalized signal is divided into a plurality of discrete command signals. The discrete command signals are used by typical converter devices which are in operational association with the prosthetic device. The converter device uses the discrete command signals for driving the moveable portions of the prosthetic device and its sub-prosthesis. The method for controlling a prosthetic device associated with the present invention comprises the steps of receiving the movement from the body part, generating a sensing signal in association with the movement of the body part, linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part, normalizing the linear signal to be a function of the entire range of the body part movement, dividing the normalized signal into a plurality of discrete command signals, and implementing the plurality of discrete command signals for driving the respective moveable prosthesis device and its sub-prosthesis.

A review of invasive and non-invasive sensory feedback in upper limb prostheses.

Science.gov (United States)

Svensson, Pamela; Wijk, Ulrika; Björkman, Anders; Antfolk, Christian

2017-06-01

The constant challenge to restore sensory feedback in prosthetic hands has provided several research solutions, but virtually none has reached clinical fruition. A prosthetic hand with sensory feedback that closely imitates an intact hand and provides a natural feeling may induce the prosthetic hand to be included in the body image and also reinforces the control of the prosthesis. Areas covered: This review presents non-invasive sensory feedback systems such as mechanotactile, vibrotactile, electrotactile and combinational systems which combine the modalities; multi-haptic feedback. Invasive sensory feedback has been tried less, because of the inherent risk, but it has successfully shown to restore some afferent channels. In this review, invasive methods are also discussed, both extraneural and intraneural electrodes, such as cuff electrodes and transverse intrafascicular multichannel electrodes. The focus of the review is on non-invasive methods of providing sensory feedback to upper-limb amputees. Expert commentary: Invoking embodiment has shown to be of importance for the control of prosthesis and acceptance by the prosthetic wearers. It is a challenge to provide conscious feedback to cover the lost sensibility of a hand, not be overwhelming and confusing for the user, and to integrate technology within the constraint of a wearable prosthesis.

Successful thrombolysis of aortic prosthetic valve thrombosis during ...

African Journals Online (AJOL)

Successful thrombolysis of aortic prosthetic valve thrombosis during first trimester of pregnancy. A Shukla, AP Raval, R Shah. Abstract. Prosthetic heart valve thrombosis during pregnancy is life-threatening. Standard surgical treatment using cardiopulmonary bypass carries high maternal and fetal complications. Here we ...

Welding of Prosthetic Alloys

Directory of Open Access Journals (Sweden)

Wojciechowska M.

2015-04-01

Full Text Available This paper presents the techniques of joining metal denture elements, used in prosthetic dentistry: the traditional soldering technique with a gas burner and a new technique of welding with a laser beam; the aim of the study was to make a comparative assessment of the quality of the joints in view of the possibility of applying them in prosthetic structures. Fractographic examinations were conducted along with tensile strength and impact strength tests, and the quality of the joints was assessed compared to the solid metal. The experiments have shown that the metal elements used to make dentures, joined by the technique which employs a laser beam, have better strength properties than those achieved with a gas burner.

Ten questions on prosthetic shoulder infection.

Science.gov (United States)

Pinder, Elizabeth M; Ong, Joshua Cy; Bale, R Stephen; Trail, Ian A

2016-07-01

Prosthetic shoulder infection can cause significant morbidity secondary to pain and stiffness. Symptoms may be present for years before diagnosis because clinical signs are often absent and inflammatory markers may be normal. An emerging common culprit, Propionibacterium acnes, is hard to culture and so prolonged incubation is necessary. A negative culture result does not always exclude infection and new synovial fluid biochemical markers such as α defensin are less sensitive than for lower limb arthroplasty. A structured approach is necessary when assessing patients for prosthetic shoulder joint infection. This includes history, examination, serum inflammatory markers, plain radiology and aspiration and/or biopsy. A classification for the likelihood of prosthetic shoulder infection has been described based on culture, pre-operative and intra-operative findings. Treatment options include antibiotic suppression, debridement with component retention, one-stage revision, two-stage revision and excision arthroplasty. Revision arthroplasty is associated with the best outcomes.

21 CFR 890.3025 - Prosthetic and orthotic accessory.

Science.gov (United States)

2010-04-01

... (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025... intended for medical purposes to support, protect, or aid in the use of a cast, orthosis (brace), or prosthesis. Examples of prosthetic and orthotic accessories include the following: A pelvic support band and...

Undergraduate prosthetics and orthotics teaching methods: A baseline for international comparison.

Science.gov (United States)

Aminian, Gholamreza; O'Toole, John M; Mehraban, Afsoon Hassani

2015-08-01

Education of Prosthetics and Orthotics is a relatively recent professional program. While there has been some work on various teaching methods and strategies in international medical education, limited publication exists within prosthetics and orthotics. To identify the teaching and learning methods that are used in Bachelor-level prosthetics and orthotics programs that are given highest priority by expert prosthetics and orthotics instructors from regions enjoying a range of economic development. Mixed method. The study partly documented by this article utilized a mixed method approach (qualitative and quantitative methods) within which each phase provided data for other phases. It began with analysis of prosthetics and orthotics curricula documents, which was followed by a broad survey of instructors in this field and then a modified Delphi process. The expert instructors who participated in this study gave high priority to student-centered, small group methods that encourage critical thinking and may lead to lifelong learning. Instructors from more developed nations placed higher priority on student's independent acquisition of prosthetics and orthotics knowledge, particularly in clinical training. Application of student-centered approaches to prosthetics and orthotics programs may be preferred by many experts, but there appeared to be regional differences in the priority given to different teaching methods. The results of this study identify the methods of teaching that are preferred by expert prosthetics and orthotics instructors from a variety of regions. This treatment of current instructional techniques may inform instructor choice of teaching methods that impact the quality of education and improve the professional skills of students. © The International Society for Prosthetics and Orthotics 2014.

Rehabilitation and Prosthetic Services

Science.gov (United States)

... Review Resources AT Education Blind Rehab Chiropractic Service Polytrauma/TBI Prosthetics & Sensory Aids Recreation Therapy More Health ... Military Sexual Trauma PTSD Research (MIRECC) Military Exposures Polytrauma Rehabilitation Spinal Cord Injury Telehealth Womens Health Issues ...

Stiffness and hysteresis properties of some prosthetic feet

NARCIS (Netherlands)

van Jaarsveld, H.W.L.; Grootenboer, H.J.; de Vries, J.; Koopman, Hubertus F.J.M.

1990-01-01

A prosthetic foot is an important element of a prosthesis, although it is not always fully recognized that the properties of the foot, along with the prosthetic knee joint and the socket, are in part responsible for the stability and metabolic energy cost during walking. The stiffness and the

Successful Management of Prosthetic Valve Brucella Endocarditis with Antibiotherapy Alone

Directory of Open Access Journals (Sweden)

José Pedro Fonseca

2018-01-01

Full Text Available Objectives: To report a case of mechanical aortic prosthesis Brucella endocarditis successfully treated with antibiotics alone. Materials and methods: We describe a clinical case and present a review of the literature. Results: A 60-year-old female farmer with a mechanical aortic prosthetic valve presented with low back pain and fever. She was diagnosed with prosthetic valve Brucella mellitensis endocarditis and was cured with antibiotic therapy alone. Few cases of successfully treated prosthetic valve Brucella endocarditis without surgery have been reported. Conclusion: Prosthetic valve Brucella endocarditis usually requires surgical valve replacement. However, selected patients may be successfully treated with antibiotic therapy alone.

Cost analysis of debridement and retention for management of prosthetic joint infection.

Science.gov (United States)

Peel, T N; Dowsey, M M; Buising, K L; Liew, D; Choong, P F M

2013-02-01

Prosthetic joint infection remains one of the most devastating complications of arthroplasty. Debridement and retention of the prosthesis is an attractive management option in carefully selected patients. Despite this, there are no data investigating the cost of this management modality for prosthetic joint infections. The aim of this case-control study was to calculate the cost associated with debridement and retention for management of prosthetic joint infection compared with primary joint replacement surgery without prosthetic joint infection. From 1 January 2008 to 30 June 2010, there were 21 prosthetic joint infections matched to 42 control patients. Controls were matched to cases according to the arthroplasty site, age and sex. Cases had a greater number of unplanned readmissions (100% vs. 7.1%; p prosthetic joint infection the total cost, including index operation and costs of management of the prosthetic joint infection, was 3.1 times the cost of primary arthoplasty; the mean cost for cases was Australian dollars (AUD) $69,414 (±29,869) compared with $22,085 (±8147) (p prosthetic joint infections will also increase, placing significant burden on the health system. Our study adds significantly to the growing body of evidence highlighting the substantial costs associated with prosthetic joint infection. © 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.

[Localized purpura revealing vascular prosthetic graft infection].

Science.gov (United States)

Boureau, A S; Lescalie, F; Cassagnau, E; Clairand, R; Connault, J

2013-07-01

Prosthetic graft infection after vascular reconstruction is a rare but serious complication. We report a case of infection occurring late after implantation of an iliofemoral prosthetic vascular graft. The Staphylococcus aureus infection was revealed by vascular purpura localized on the right leg 7 years after implantation of a vascular prosthesis. This case illustrates an uncommonly late clinical manifestation presenting as an acute infection 7 years after the primary operation. In this situation, the presentation differs from early infection, which generally occurs within the first four postoperative months. Diagnosis and treatment remain a difficult challenge because prosthetic graft infection is a potentially life-threatening complication. Morbidity and mortality rates are high. Here we detail specific aspects of the clinical and radiological presentation. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Salmonella Typhimurium gastroenteritis leading to chronic prosthetic vascular graft infection.

Science.gov (United States)

Cullinan, Milo; Clarke, Michael; Dallman, Tim; Peart, Steven; Wilson, Deborah; Weiand, Daniel

2017-08-01

Introduction. It is estimated up to 6 % of prosthetic vascular grafts become infected. Staphylococcus aureus is predominant in early infection and coagulase-negative staphylococci are predominant in late infections. Enterobacteriaceae cause 14-40 % of prosthetic vascular graft infections. This is, to our knowledge the first reported case of Salmonella gastroenteritis causing chronic prosthetic vascular graft infection (PVGI). Case presentation. A 57 years old lady presented with signs and symptoms of prosthetic vascular graft infection. Three years earlier, she had undergone a prosthetic axillo-femoral bypass graft for critical limb ischaemia. The infected prosthetic vascular graft was removed and Salmonella Typhimurium was isolated on culture. In the intervening period, Salmonella Typhimurium was isolated from a faecal specimen, collected during an episode of acute gastroenteritis. Whole-genome sequencing (WGS) showed that the respective Salmonella Typhimurium isolates differed by only a single nucleotide polymorphism (SNP). Salmonella Typhimurium was not isolated on culture of a faecal specimen collected five days following cessation of antimicrobial therapy. Six months after removal of the prosthetic graft, the patient remains under follow-up for her peripheral vascular disease, which currently requires no further surgical intervention. Conclusion. This case has clear implications for the management of chronic PVGI. It is vital to collect high-quality surgical specimens for microbiological analysis and empirical choices of antibiotics are unlikely to cover all potential pathogens. It may also be prudent to enquire about a history of acute gastroenteritis when assessing patients presenting with chronic PVGI.

Provision of Prosthetic Services Following Lower Limb Amputation in Malaysia

Science.gov (United States)

Arifin, Nooranida; Hasbollah, Hasif Rafidee; Hanafi, Muhammad Hafiz; Ibrahim, Al Hafiz; Rahman, Wan Afezah Wan Abdul; Aziz, Roslizawati Che

2017-01-01

The incidence of lower limb amputation is high across the globe and continues to be a major threat to morbidity and mortality. Consequently, the provision of high quality and effective prosthetics services have been known as an essential component for a successful rehabilitation outcome. In Malaysia, amputation prevalence has been increasing in which several main components of service delivering aspects (such as service intervention, prosthetic personnel) should be anticipated to accommodate for the increasing demand. This article highlights the hurdles experienced in providing prosthetic services in Malaysia from multiple aspects such as financial burden to acquire the prosthesis and lack of expertise to produce quality prosthesis. This paramount issues consequently justify for the urgency to carry out national level survey on the current statistics of lower limb amputation and to ascertain the available workforce to provide a quality prosthetics services. Only with accurate and current information from the national survey, strategies and policies aimed at enhancing the outcome from prosthetics services can be achieved. PMID:29386978

Prosthetic Status and Prosthetic Need Among the Patients Attending Various Dental Institutes of Ahmedabad and Gandhinagar District, Gujarat

OpenAIRE

Shah, Vrinda R.; Shah, Darshana N.; Parmar, Chaitanya H.

2012-01-01

The oral health being an integral part for the healthy living, necessity of disability limitation and rehabilitation in oral health has taken a paramount role. To assess the prosthetic status and to evaluate the prosthetic needs of the patients attending various institutes of Ahmedabad and Gandhinagar district. A total of 510 (264 males and 246 females) subjects at various dental institutes were examined in the study. A survey proforma was prepared with the help of WHO oral health assessment ...

Prosthetic Jamming Terminal Device: A Case Study of Untethered Soft Robotics.

Science.gov (United States)

Cheng, Nadia; Amend, John; Farrell, Todd; Latour, Debra; Martinez, Carlos; Johansson, Jen; McNicoll, Anthony; Wartenberg, Marek; Naseef, Samuel; Hanson, William; Culley, William

2016-12-01

This article illuminates the major and often overlooked challenge of untethering soft robotic systems through the context of recent work, in which soft robotic gripper technology enabled by jamming of granular media was applied to a prosthetic jamming terminal device (PJTD). The PJTD's technical and market feasibility was evaluated in a pilot study with two upper-limb amputees. A PJTD prototype was tested against a commercial device (Motion Control electric terminal service with a one degree-of-freedom pinching mechanism) using two existing hand function tests: the first quantified the device's speed in picking and placing small blocks and the second evaluated a person's ability to perform activities of daily living (ADLs). The PJTD prototype performed slightly slower than its commercial counterpart in the first test. While both participants successfully completed all the ADLs with both devices in the second test, the commercial device scored marginally higher. Results suggested that PJTD can have potential benefits over existing terminal devices, such as providing the capability to firmly grasp tools due to the ability of PJTD to conform to arbitrary surfaces and reducing compensatory shoulder movements due to its axisymmetric design. Some downsides were that users reported fatigue while operating the PJTD, as most operations require pushing the PJTD against target objects to adequately conform to them. The greatest drawback for the PJTD is also a major roadblock preventing a number of soft robotic research projects from making an impact in real-world applications: pneumatic technology required for operating the PJTD is currently too large and heavy to enable compact untethered operation.

Fabrication and characterization of bending and pressure sensors for a soft prosthetic hand

Science.gov (United States)

Rocha, Rui Pedro; Alhais Lopes, Pedro; de Almeida, Anibal T.; Tavakoli, Mahmoud; Majidi, Carmel

2018-03-01

We demonstrate fabrication, characterization, and implementation of ‘soft-matter’ pressure and bending sensors for a soft robotic hand. The elastomer-based sensors are embedded in a robot finger composed of a 3D printed endoskeleton and covered by an elastomeric skin. Two types of sensors are evaluated, resistive pressure sensors and capacitive pressure sensors. The sensor is fabricated entirely out of insulating and conductive rubber, the latter composed of polydimethylsiloxane (PDMS) elastomer embedded with a percolating network of structured carbon black (CB). The sensor-integrated fingers have a simple materials architecture, can be fabricated with standard rapid prototyping methods, and are inexpensive to produce. When incorporated into a robotic hand, the CB-PDMS sensors and PDMS carrier medium function as an ‘artificial skin’ for touch and bend detection. Results show improved response with a capacitive sensor architecture, which, unlike a resistive sensor, is robust to electromechanical hysteresis, creep, and drift in the CB-PDMS composite. The sensorized fingers are integrated in an anthropomorphic hand and results for a variety of grasping tasks are presented.

Hand biometric recognition based on fused hand geometry and vascular patterns.

Science.gov (United States)

Park, GiTae; Kim, Soowon

2013-02-28

A hand biometric authentication method based on measurements of the user's hand geometry and vascular pattern is proposed. To acquire the hand geometry, the thickness of the side view of the hand, the K-curvature with a hand-shaped chain code, the lengths and angles of the finger valleys, and the lengths and profiles of the fingers were used, and for the vascular pattern, the direction-based vascular-pattern extraction method was used, and thus, a new multimodal biometric approach is proposed. The proposed multimodal biometric system uses only one image to extract the feature points. This system can be configured for low-cost devices. Our multimodal biometric-approach hand-geometry (the side view of the hand and the back of hand) and vascular-pattern recognition method performs at the score level. The results of our study showed that the equal error rate of the proposed system was 0.06%.

Adaptive sports technology and biomechanics: prosthetics.

Science.gov (United States)

De Luigi, Arthur Jason; Cooper, Rory A

2014-08-01

With the technologic advances in medicine and an emphasis on maintaining physical fitness, the population of athletes with impairments is growing. It is incumbent upon health care practitioners to make every effort to inform these individuals of growing and diverse opportunities and to encourage safe exercise and athletic participation through counseling and education. Given the opportunities for participation in sports for persons with a limb deficiency, the demand for new, innovative prosthetic designs is challenging the clinical and technical expertise of the physician and prosthetist. When generating a prosthetic prescription, physicians and prosthetists should consider the needs and preferences of the athlete with limb deficiency, as well as the functional demands of the chosen sporting activity. The intent of this article is to provide information regarding the current advancements in the adaptive sports technology and biomechanics in the field of prosthetics, and to assist clinicians and their patients in facilitating participation in sporting activities. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Periprosthetic joint infection: are patients with multiple prosthetic joints at risk?

Science.gov (United States)

Jafari, S Mehdi; Casper, David S; Restrepo, Camilo; Zmistowski, Benjamin; Parvizi, Javad; Sharkey, Peter F

2012-06-01

Patients who present with a periprosthetic joint infection in a single joint may have multiple prosthetic joints. The risk of these patients developing a subsequent infection in another prosthetic joint is unknown. Our purposes were (1) to identify the risk of developing a subsequent infection in another prosthetic joint and (2) to describe the time span and organism profile to the second prosthetic infection. We retrospectively identified 55 patients with periprosthetic joint infection who had another prosthetic joint in place at the time of presentation. Of the 55 patients, 11 (20%) developed a periprosthetic joint infection in a second joint. The type of organism was the same as the first infection in 4 (36%) of 11 patients. The time to developing a second infection averaged 2.0 years (range, 0-6.9 years). Copyright © 2012 Elsevier Inc. All rights reserved.

Uncemented allograft-prosthetic composite reconstruction of the proximal femur

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Li Min

2014-01-01

Full Text Available Background: Allograft-prosthetic composite can be divided into three groups names cemented, uncemented, and partially cemented. Previous studies have mainly reported outcomes in cemented and partially cemented allograft-prosthetic composites, but have rarely focused on the uncemented allograft-prosthetic composites. The objectives of our study were to describe a surgical technique for using proximal femoral uncemented allograft-prosthetic composite and to present the radiographic and clinical results. Materials and Methods: Twelve patients who underwent uncemented allograft-prosthetic composite reconstruction of the proximal femur after bone tumor resection were retrospectively evaluated at an average followup of 24.0 months. Clinical records and radiographs were evaluated. Results: In our series, union occurred in all the patients (100%; range 5-9 months. Until the most recent followup, there were no cases with infection, nonunion of the greater trochanter, junctional bone resorption, dislocation, allergic reaction, wear of acetabulum socket, recurrence, and metastasis. But there were three periprosthetic fractures which were fixed using cerclage wire during surgery. Five cases had bone resorption in and around the greater trochanter. The average Musculoskeletal Tumor Society (MSTS score and Harris hip score (HHS were 26.2 points (range 24-29 points and 80.6 points (range 66.2-92.7 points, respectively. Conclusions: These results showed that uncemented allograft-prosthetic composite could promote bone union through compression at the host-allograft junction and is a good choice for proximal femoral resection. Although this technology has its own merits, long term outcomes are yet not validated.

Prosthetic implant treatment of the edentulous maxilla with overdenture.

Science.gov (United States)

Inversini, M

2006-10-01

The literature concerning the success of prosthetic implant treatment with maxillary overdenture is reviewed, and variables affecting treatment from the implant and prosthetic standpoint are analysed. Guidelines for the fabrication of maxillary overimplants comparable to those for mandibular overimplants are still lacking, as are evidence-based prosthetic design concepts. Individual methods and techniques have been described, but evaluation standards for the outcome of maxillary prosthetic-implant treatment are lacking or individually interpreted. The biomechanics involved in the proposed system are described, together with the advantages of telescopic crowns for the retention of removable partial prosthesis supported by maxillary implants. The positive influence, in terms of long-term prognosis, of the perio-protective design of removable partial prostheses supported by maxillary overimplants is also discussed. The proposed system not only provides stability, support and retention for removable partial prostheses supported by maxillary implants, but also enables implant survival rates to be improved, both for biomechanical reasons and due to improved oral hygiene. The simplification of fabrication procedures, repair, rebasing and re-operating also reduce the cost of follow-up and improve the cost/benefit ratio. However, additional studies are needed to clarify the number and most appropriate distribution of implants, as well as the most favourable prosthetic designs for maxillary overimplants.

Surgical-prosthetic treatment of large mandibular cysts

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Džambas Ljubiša D.

2003-01-01

Full Text Available This paper presents a combined surgical-prosthetic procedure of reconstructing mandibular bone defect in a 53 year old patient, following enucleation of a mandibular cyst (Cystectomy Partsch II. After a thorough diagnostic evaluation, a surgical procedure was planned with the particular attention to the nature of the disease, patient’s condition, size and extension of the cyst, tissue loss, and the possibilities of prosthetic management of a mandibular bone defect with partial postresection dental prosthesis. It is of great importance to point to the significance of teamwork of a maxillofacial surgeon and a specialist in prosthodontics. This kind of cooperation provided very effective and less risky soft tissue, as well as bone tissue regeneration (osteogenesis. The patient’s recovery was fast, and he could return to his daily activities and work without significant changes regarding quality of life after surgery and prosthetic treatment.

Prosthetics in Paediatric Dentistry

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Vulićević Zoran

2017-07-01

Full Text Available Premature loss of teeth in children may lead to both functional and esthetic problems. Missing teeth in both anterior and posterior regions may cause malfunctions in mastication and proper pronunciation. If the missing teeth are not replaced, further complications may occur, including adjacent tooth migration, loss of alveolar bone, and irregular occlusion. Considering the sensitive nature of children, loss of teeth may cause the development of insecurities and low self esteem problems. Due to dynamic nature of growth in children and adolescents, prosthetic appliances must not hinder development of orofacial system, and must meet adequate esthetic and functional standards. Dental prosthetic appliances in paediatrics must be planned with respect to the special conditions that led to tooth loss or damage. Multi-disciplinary approach is needed, under constant supervision of paediatric dentist and orthodontist, as well as regular checkups with clinical and radiographical examinations.

Custom-made laser-welded titanium implant prosthetic abutment.

Science.gov (United States)

Iglesia-Puig, Miguel A

2005-10-01

A technique to create an individually modified implant prosthetic abutment is described. An overcasting is waxed onto a machined titanium abutment, cast in titanium, and joined to it with laser welding. With the proposed technique, a custom-made titanium implant prosthetic abutment is created with adequate volume and contour of metal to support a screw-retained, metal-ceramic implant-supported crown.

Prosthetic Rehabilitation in Children: An Alternative Clinical Technique

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Nádia Carolina Teixeira Marques

2013-01-01

Full Text Available Complete and partial removable dentures have been used successfully in numerous patients with oligodontia and/or anodontia. However, there is little information in the literature regarding the principles and guidelines to prosthetic rehabilitation for growing children. This case report describes the management of a young child with oligodontia as well as the treatment planning and the prosthetic rehabilitation technique.

A natural approach to convey numerical digits using hand activity recognition based on hand shape features

Science.gov (United States)

Chidananda, H.; Reddy, T. Hanumantha

2017-06-01

This paper presents a natural representation of numerical digit(s) using hand activity analysis based on number of fingers out stretched for each numerical digit in sequence extracted from a video. The analysis is based on determining a set of six features from a hand image. The most important features used from each frame in a video are the first fingertip from top, palm-line, palm-center, valley points between the fingers exists above the palm-line. Using this work user can convey any number of numerical digits using right or left or both the hands naturally in a video. Each numerical digit ranges from 0 to9. Hands (right/left/both) used to convey digits can be recognized accurately using the valley points and with this recognition whether the user is a right / left handed person in practice can be analyzed. In this work, first the hand(s) and face parts are detected by using YCbCr color space and face part is removed by using ellipse based method. Then, the hand(s) are analyzed to recognize the activity that represents a series of numerical digits in a video. This work uses pixel continuity algorithm using 2D coordinate geometry system and does not use regular use of calculus, contours, convex hull and datasets.

Mesofluidic controlled robotic or prosthetic finger

Science.gov (United States)

Lind, Randall F; Jansen, John F; Love, Lonnie J

2013-11-19

A mesofluidic powered robotic and/or prosthetic finger joint includes a first finger section having at least one mesofluidic actuator in fluid communication with a first actuator, a second mesofluidic actuator in fluid communication with a second actuator and a second prosthetic finger section pivotally connected to the first finger section by a joint pivot, wherein the first actuator pivotally cooperates with the second finger to provide a first mechanical advantage relative to the joint point and wherein the second actuator pivotally cooperates with the second finger section to provide a second mechanical advantage relative to the joint point.

Hand Biometric Recognition Based on Fused Hand Geometry and Vascular Patterns

Science.gov (United States)

Park, GiTae; Kim, Soowon

2013-01-01

A hand biometric authentication method based on measurements of the user's hand geometry and vascular pattern is proposed. To acquire the hand geometry, the thickness of the side view of the hand, the K-curvature with a hand-shaped chain code, the lengths and angles of the finger valleys, and the lengths and profiles of the fingers were used, and for the vascular pattern, the direction-based vascular-pattern extraction method was used, and thus, a new multimodal biometric approach is proposed. The proposed multimodal biometric system uses only one image to extract the feature points. This system can be configured for low-cost devices. Our multimodal biometric-approach hand-geometry (the side view of the hand and the back of hand) and vascular-pattern recognition method performs at the score level. The results of our study showed that the equal error rate of the proposed system was 0.06%. PMID:23449119

Real-time myoelectric control of a multi-fingered hand prosthesis using principal components analysis

Directory of Open Access Journals (Sweden)

Matrone Giulia C

2012-06-01

Full Text Available Abstract Background In spite of the advances made in the design of dexterous anthropomorphic hand prostheses, these sophisticated devices still lack adequate control interfaces which could allow amputees to operate them in an intuitive and close-to-natural way. In this study, an anthropomorphic five-fingered robotic hand, actuated by six motors, was used as a prosthetic hand emulator to assess the feasibility of a control approach based on Principal Components Analysis (PCA, specifically conceived to address this problem. Since it was demonstrated elsewhere that the first two principal components (PCs can describe the whole hand configuration space sufficiently well, the controller here employed reverted the PCA algorithm and allowed to drive a multi-DoF hand by combining a two-differential channels EMG input with these two PCs. Hence, the novelty of this approach stood in the PCA application for solving the challenging problem of best mapping the EMG inputs into the degrees of freedom (DoFs of the prosthesis. Methods A clinically viable two DoFs myoelectric controller, exploiting two differential channels, was developed and twelve able-bodied participants, divided in two groups, volunteered to control the hand in simple grasp trials, using forearm myoelectric signals. Task completion rates and times were measured. The first objective (assessed through one group of subjects was to understand the effectiveness of the approach; i.e., whether it is possible to drive the hand in real-time, with reasonable performance, in different grasps, also taking advantage of the direct visual feedback of the moving hand. The second objective (assessed through a different group was to investigate the intuitiveness, and therefore to assess statistical differences in the performance throughout three consecutive days. Results Subjects performed several grasp, transport and release trials with differently shaped objects, by operating the hand with the myoelectric

Selection of suitable hand gestures for reliable myoelectric human computer interface.

Science.gov (United States)

Castro, Maria Claudia F; Arjunan, Sridhar P; Kumar, Dinesh K

2015-04-09

Myoelectric controlled prosthetic hand requires machine based identification of hand gestures using surface electromyogram (sEMG) recorded from the forearm muscles. This study has observed that a sub-set of the hand gestures have to be selected for an accurate automated hand gesture recognition, and reports a method to select these gestures to maximize the sensitivity and specificity. Experiments were conducted where sEMG was recorded from the muscles of the forearm while subjects performed hand gestures and then was classified off-line. The performances of ten gestures were ranked using the proposed Positive-Negative Performance Measurement Index (PNM), generated by a series of confusion matrices. When using all the ten gestures, the sensitivity and specificity was 80.0% and 97.8%. After ranking the gestures using the PNM, six gestures were selected and these gave sensitivity and specificity greater than 95% (96.5% and 99.3%); Hand open, Hand close, Little finger flexion, Ring finger flexion, Middle finger flexion and Thumb flexion. This work has shown that reliable myoelectric based human computer interface systems require careful selection of the gestures that have to be recognized and without such selection, the reliability is poor.

Dexterous hand gestures recognition based on low-density sEMG signals for upper-limb forearm amputees

Directory of Open Access Journals (Sweden)

John Jairo Villarejo Mayor

2017-08-01

Full Text Available Abstract Introduction Intuitive prosthesis control is one of the most important challenges in order to reduce the user effort in learning how to use an artificial hand. This work presents the development of a novel method for pattern recognition of sEMG signals able to discriminate, in a very accurate way, dexterous hand and fingers movements using a reduced number of electrodes, which implies more confidence and usability for amputees. Methods The system was evaluated for ten forearm amputees and the results were compared with the performance of able-bodied subjects. Multiple sEMG features based on fractal analysis (detrended fluctuation analysis and Higuchi’s fractal dimension combined with traditional magnitude-based features were analyzed. Genetic algorithms and sequential forward selection were used to select the best set of features. Support vector machine (SVM, K-nearest neighbors (KNN and linear discriminant analysis (LDA were analyzed to classify individual finger flexion, hand gestures and different grasps using four electrodes, performing contractions in a natural way to accomplish these tasks. Statistical significance was computed for all the methods using different set of features, for both groups of subjects (able-bodied and amputees. Results The results showed average accuracy up to 99.2% for able-bodied subjects and 98.94% for amputees using SVM, followed very closely by KNN. However, KNN also produces a good performance, as it has a lower computational complexity, which implies an advantage for real-time applications. Conclusion The results show that the method proposed is promising for accurately controlling dexterous prosthetic hands, providing more functionality and better acceptance for amputees.

Fixed prosthetic treatment in patients with cleft lip and palate

Directory of Open Access Journals (Sweden)

Bajevska Jagoda

2017-01-01

Full Text Available Introduction. The prosthetic treatment of patients with cleft palate includes various treatment options such as fixed partial dentures, removable partial prosthesis, etc. The type of prosthetic appliance is determined by the oral health of each individual and the circumstances. We presented three adult patients with the cleft lip and palate subjected to prosthetic treatment. Case report. From the possible prosthetic solutions according to the conditions in the oral cavity and the circumstances, fixed partial dentures veneered with composite or ceramic were chosen. A proper relationship between the teeth was reached with the fixed partial dentures, and function established, the phonetics improved and satisfying aesthetics effect accomplished improving the profile appearance of the patient’s face. Plastic surgery of the nose was performed after that. Conclusion. Multidisclipinary treatment is necessary for favourable long-term outcome in cleft lip and palate patients.

[Study on an Exoskeleton Hand Function Training Device].

Science.gov (United States)

Hu, Xin; Zhang, Ying; Li, Jicai; Yi, Jinhua; Yu, Hongliu; He, Rongrong

2016-02-01

Based on the structure and motion bionic principle of the normal adult fingers, biological characteristics of human hands were analyzed, and a wearable exoskeleton hand function training device for the rehabilitation of stroke patients or patients with hand trauma was designed. This device includes the exoskeleton mechanical structure and the electromyography (EMG) control system. With adjustable mechanism, the device was capable to fit different finger lengths, and by capturing the EMG of the users' contralateral limb, the motion state of the exoskeleton hand was controlled. Then driven by the device, the user's fingers conducting adduction/abduction rehabilitation training was carried out. Finally, the mechanical properties and training effect of the exoskeleton hand were verified through mechanism simulation and the experiments on the experimental prototype of the wearable exoskeleton hand function training device.

Prosthetic Mitral Valve Leaflet Escape

Science.gov (United States)

Kim, Darae; Hun, Sin Sang; Cho, In-Jeong; Shim, Chi-Young; Ha, Jong-Won; Chung, Namsik; Ju, Hyun Chul; Sohn, Jang Won

2013-01-01

Leaflet escape of prosthetic valve is rare but potentially life threatening. It is essential to make timely diagnosis in order to avoid mortality. Transesophageal echocardiography and cinefluoroscopy is usually diagnostic and the location of the missing leaflet can be identified by computed tomography (CT). Emergent surgical correction is mandatory. We report a case of fractured escape of Edward-Duromedics mitral valve 27 years after the surgery. The patient presented with symptoms of acute decompensated heart failure and cardiogenic shock. She was instantly intubated and mechanically ventilated. After prompt evaluation including transthoracic echocardiography and CT, the escape of the leaflet was confirmed. The patient underwent emergent surgery for replacement of the damaged prosthetic valves immediately. Eleven days after the surgery, the dislodged leaflet in iliac artery was removed safely and the patient recovered well. PMID:23837121

A need for a more user-centered design in body powered prostheses

NARCIS (Netherlands)

Hichert, M.; Plettenburg, D.H.; Vardy, A.N.; Will, Wendy; Scheme, Erik

2014-01-01

Users of body powered prostheses (BPP) complain about too high operating forces, leading to pain and/or fatigue during or after prosthetic operation. In the worst case nerve and vessel damage can occur [1, 2], leading to nonuse of prostheses. Smit et al. investigated cable forces and displacements

Adapting to change: influence of a microprocessor-controlled prosthetic knee on gait adaptations

NARCIS (Netherlands)

Prinsen, Erik Christiaan

2016-01-01

Advancement in prosthetic knee design have led to the introduction of microprocessor-controlled prosthetic knees (MPKs). MPKs incorporate sensors that are able to measure prosthetic loading, the knee angle, and knee angular velocity. Based on the sensor information, MPKs determine the optimal level

Implant salvage in breast reconstruction with severe peri-prosthetic infection.

Science.gov (United States)

Meybodi, Farid; Sedaghat, Negin; French, James; Keighley, Caitlin; Mitchell, David; Elder, Elisabeth

2017-12-01

Although treatment of mild peri-prosthetic infection in implant-based breast reconstruction results in high rates of resolution, successful management of severe peri-prosthetic infection remains a significant challenge. In this case series, a protocol utilizing a novel dressing - negative pressure wound therapy with instillation (NPWTi) - for the management of severe peri-prosthetic infection in breast reconstruction patients is described. This is an operative technique involving: (i) explantation of the breast prosthesis and application of the NPWTi dressing to the implant pocket; (ii) change of the NPWTi dressing; (iii) intraoperative fluid/tissue cultures; and (iv) reimplantation of the breast prosthesis when cultures yield no growth. This protocol was utilized in six cases of severe peri-prosthetic infection in five patients with immediate breast reconstruction for breast cancer or risk-reducing surgery. Cultures of fluid/tissue grew typical and/or unusual organisms. Only one case did not yield an organism. The hospital length of stay upon completion of the protocol ranged from 7-16 days (mean, 12 days). Successful implant salvage was achieved in five of six cases. The protocol was aborted in one case to allow for completion of adjuvant chemotherapy. Early findings from this case series suggest that in cases of severe peri-prosthetic infection this novel operative protocol may result in successful implant salvage for breast reconstruction patients. Further studies are needed to more fully elaborate the role of NPWTi to achieve implant salvage in challenging cases of peri-prosthetic infection. © 2015 Royal Australasian College of Surgeons.

Prosthetic prescription in the Netherlands: An interview with clinical experts

NARCIS (Netherlands)

Van Der Linde, H.; Geertzen, J.H.B.; Hofstad, C.J.; Van Limbeek, Jacques; Postema, K.

2004-01-01

In the process of guideline development for prosthetic prescription in the Netherlands the authors made a study of the daily clinical practice of lower limb prosthetics. Besides the evidence-based knowledge from literature the more implicit knowledge from clinical experts is of importance for

PLANNING OF IMPLANTO‐PROSTHETIC STRUCTURES IN TOTAL EDENTATION ACCORDING TO BIOMECHANICAL CRITERIA

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N. VASILE

2013-07-01

Full Text Available Scope of the study: Analysis of the biomechanical aspects of the implanto‐prosthetic structures for planning the treatment in cases of total edentation.Materials and method: The study was performed in the Clinics of Prosthetics and Oral Implantology, Military Emergency Hospital of Sibiu, on a group of mandibularly totally edentated patients. Planning of the implanto‐pros‐ thetic treatment had in view the peculiarities of total man‐ dibular edentation and observance of the biomechanical principles. Selection of the type of occlusion restoration considered the presence of parafunctions and the nature of the antagonistic arch. Special attention was paid to the direction and intensity of the forces acting in the region of the future prosthetic work. When bruxism was manifested, its preimplantary removal was compulsory.Results and discussion: In fixed prosthetic restaurati‐ ons applied on implants, distribuition of forces obviously depend on the quality of osteo‐acceptance, as well, and also on the elasticity degree of the prosthetic work. In the case of mobilized prosthetic restorations supported on implants, rigidization of implants from the anterior region of the mandible may be obtained by means of a bar. In decreasing order of their elasticity, the materials employed are: acrylate, composites, noble and seminoble alloys, other metals, ceramics. Ceramics confers maximum stability to implants, yet without redeeming the forces. For amortizing the forces and for a progressive charging of the implants, it is recommended that the first (temporary prosthetic restorations should be made of either acrylate or compo‐ sites.Conclusions. Observance of the occlusological princi‐ ples in cases of occlusal reconstruction represents the determining element which assures the osteo‐acceptance of implants and the integrity of prosthetic restaurations.

Applying Space Technology to Enhance Control of an Artificial Arm for Children and Adults With Amputations

Science.gov (United States)

Atkins, Diane J.

1998-01-01

The first single function myoelectric prosthetic hand was introduced in the 1960's. This hand was controlled by the electric fields generated by muscle contractions in the residual limb of the amputee user. Electrodes and amplifiers, embedded in the prosthetic socket, measured these electric fields across the skin, which increase in amplitude as the individual contracts their muscle. When the myoelectric signal reached a certain threshold amplitude, the control unit activated a motor which opened or closed a hand-like prosthetic terminal device with a pincher grip. Late in the 1990's, little has changed. Most current myoelectric prostheses still operate in this same, single-function way. To better understand the limitations of the current single-function myoelectric hand and the needs of those who use them, The Institute for Rehabilitation and Research (TIRR), sponsored by the National Institutes of Health (NUH), surveyed approximately 2,500 individuals with upper limb loss [1]. When asked to identify specific features of their current myoelectric prostheses that needed improvement, the survey respondents overwhelmingly identified the lack of wrist and finger movement, as well as poor control capability. However, simply building a mechanism with individual finger and wrist motion is not enough. In the 1960's and 1970's, engineers built a number of more dexterous prosthetic hands. Unfortunately, these were rejected during clinical trials due to a difficult and distracting control interface. The goal of this project, "Applying Space Technology to Enhance Control of an Artificial Arm for Children and Adults with Amputations," was to lay the foundation for a multi-function, intuitive myoelectric control system which requires no conscious thought to move the hand. We built an extensive myoelectric signal database for six motions from ten amputee volunteers, We also tested a control system based on new artificial intelligence techniques on the data from two of these

Vascular complications of prosthetic inter-vertebral discs.

Science.gov (United States)

Daly, Kevin J; Ross, E Raymond S; Norris, Heather; McCollum, Charles N

2006-10-01

Five consecutive cases of prosthetic inter-vertebral disc displacement with severe vascular complications on revisional surgery are described. The objective of this case report is to warn spinal surgeons that major vascular complications are likely with anterior displacement of inter-vertebral discs. We have not been able to find a previous report on vascular complications associated with anterior displacement of prosthetic inter-vertebral discs. In all five patients the prosthetic disc had eroded into the bifurcation of the inferior vena cava and the left common iliac vein. In three cases the aortic bifurcation was also involved. The fibrosis was so severe that dissecting out the arteries and veins to provide access to the relevant disc proved impossible. Formal division of the left common iliac vein and artery with subsequent repair was our solution. Anterior inter-vertebral disc displacement was associated with severe vascular injury. Preventing anterior disc displacement is essential in disc design. In the event of anterior displacement, disc removal should be planned with a Vascular Surgeon.

Control system and method for prosthetic devices

Science.gov (United States)

Bozeman, Richard J., Jr. (Inventor)

1992-01-01

A control system and method for prosthetic devices is provided. The control system comprises a transducer for receiving movement from a body part for generating a sensing signal associated with that movement. The sensing signal is processed by a linearizer for linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part. The linearized sensing signal is normalized to be a function of the entire range of body part movement from the no-shrug position of the movable body part through the full-shrug position of the movable body part. The normalized signal is divided into a plurality of discrete command signals. The discrete command signals are used by typical converter devices which are in operational association with the prosthetic device. The converter device uses the discrete command signals for driving the movable portions of the prosthetic device and its sub-prosthesis. The method for controlling a prosthetic device associated with the present invention comprises the steps of receiving the movement from the body part, generating a sensing signal in association with the movement of the body part, linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part, normalizing the linear signal to be a function of the entire range of the body part movement, dividing the normalized signal into a plurality of discrete command signals, and implementing the plurality of discrete command signals for driving the respective movable prosthesis device and its sub-prosthesis.

A computational method for comparing the behavior and possible failure of prosthetic implants

Energy Technology Data Exchange (ETDEWEB)

Nielsen, C.; Hollerbach, K.; Perfect, S.; Underhill, K.

1995-05-01

Prosthetic joint implants currently in use exhibit high Realistic computer modeling of prosthetic implants provides an opportunity for orthopedic biomechanics researchers and physicians to understand possible in vivo failure modes, without having to resort to lengthy and costly clinical trials. The research presented here is part of a larger effort to develop realistic models of implanted joint prostheses. The example used here is the thumb carpo-metacarpal (cmc) joint. The work, however, can be applied to any other human joints for which prosthetic implants have been designed. Preliminary results of prosthetic joint loading, without surrounding human tissue (i.e., simulating conditions under which the prosthetic joint has not yet been implanted into the human joint), are presented, based on a three-dimensional, nonlinear finite element analysis of three different joint implant designs.

Gonococcal Prosthetic Joint Infection.

Science.gov (United States)

Gassiep, Ian; Gilpin, Bradley; Douglas, Joel; Siebert, David

2017-01-01

Neisseria gonorrhoea is a common sexually transmitted infection worldwide. Disseminated gonococcal infection is an infrequent presentation and rarely can be associated with septic arthritis. Incidence of this infection is rising, both internationally and in older age groups. We present the first documented case of N. gonorrhoea prosthetic joint infection which was successfully treated with laparoscopic debridement and antimicrobial therapy.

Visuo-Haptic Mixed Reality with Unobstructed Tool-Hand Integration.

Science.gov (United States)

Cosco, Francesco; Garre, Carlos; Bruno, Fabio; Muzzupappa, Maurizio; Otaduy, Miguel A

2013-01-01

Visuo-haptic mixed reality consists of adding to a real scene the ability to see and touch virtual objects. It requires the use of see-through display technology for visually mixing real and virtual objects, and haptic devices for adding haptic interaction with the virtual objects. Unfortunately, the use of commodity haptic devices poses obstruction and misalignment issues that complicate the correct integration of a virtual tool and the user's real hand in the mixed reality scene. In this work, we propose a novel mixed reality paradigm where it is possible to touch and see virtual objects in combination with a real scene, using commodity haptic devices, and with a visually consistent integration of the user's hand and the virtual tool. We discuss the visual obstruction and misalignment issues introduced by commodity haptic devices, and then propose a solution that relies on four simple technical steps: color-based segmentation of the hand, tracking-based segmentation of the haptic device, background repainting using image-based models, and misalignment-free compositing of the user's hand. We have developed a successful proof-of-concept implementation, where a user can touch virtual objects and interact with them in the context of a real scene, and we have evaluated the impact on user performance of obstruction and misalignment correction.

Tingling/numbness in the hands of computer users: neurophysiological findings from the NUDATA study

DEFF Research Database (Denmark)

Overgaard, E.; Brandt, L. P.; Ellemann, K.

2004-01-01

OBJECTIVES: To investigate whether tingling/numbness of the hands and fingers among computer users is associated with elevated vibration threshold as a sign of early nerve compression. METHODS: Within the Danish NUDATA study, vibratory sensory testing with monitoring of the digital vibration...... once a week or daily within the last 3 months. Participants with more than slight muscular pain or disorders of the neck and upper extremities, excessive alcohol consumption, previous injuries of the upper extremities, or concurrent medical diseases were excluded. The two groups had a similar amount...... of work with mouse, keyboard, and computer. RESULTS: Seven of the 20 cases (35%) had elevated vibration thresholds, compared with 3 of the 20 controls (15%); this difference was not statistically significant (chi2=2.13, P=0.14). Compared with controls, cases had increased perception threshold for all...

Design and Evaluation of a Prosthetic Knee Joint Using the Geared Five-Bar Mechanism.

Science.gov (United States)

Sun, Yuanxi; Ge, Wenjie; Zheng, Jia; Dong, Dianbiao

2015-11-01

This paper presents the mechanical design, dynamics analysis and ankle trajectory analysis of a prosthetic knee joint using the geared five-bar mechanism. Compared with traditional four-bar or six-bar mechanisms, the geared five-bar mechanism is better at performing diverse movements and is easy to control. This prosthetic knee joint with the geared five-bar mechanism is capable of fine-tuning its relative instantaneous center of rotation and ankle trajectory. The centrode of this prosthetic knee joint, which is mechanically optimized according to the centrode of human knee joint, is better in the bionic performance than that of a prosthetic knee joint using the four-bar mechanism. Additionally, the stability control of this prosthetic knee joint during the swing and stance phase is achieved by a motor. By adjusting the gear ratio of this prosthetic knee joint, the ankle trajectories of both unilateral and bilateral amputees show less deviations from expected than that of the four-bar knee joint.

Reduced prosthetic stiffness lowers the metabolic cost of running for athletes with bilateral transtibial amputations.

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Beck, Owen N; Taboga, Paolo; Grabowski, Alena M

2017-04-01

Inspired by the springlike action of biological legs, running-specific prostheses are designed to enable athletes with lower-limb amputations to run. However, manufacturer's recommendations for prosthetic stiffness and height may not optimize running performance. Therefore, we investigated the effects of using different prosthetic configurations on the metabolic cost and biomechanics of running. Five athletes with bilateral transtibial amputations each performed 15 trials on a force-measuring treadmill at 2.5 or 3.0 m/s. Athletes ran using each of 3 different prosthetic models (Freedom Innovations Catapult FX6, Össur Flex-Run, and Ottobock 1E90 Sprinter) with 5 combinations of stiffness categories (manufacturer's recommended and ± 1) and heights (International Paralympic Committee's maximum competition height and ± 2 cm) while we measured metabolic rates and ground reaction forces. Overall, prosthetic stiffness [fixed effect (β) = 0.036; P = 0.008] but not height ( P ≥ 0.089) affected the net metabolic cost of transport; less stiff prostheses reduced metabolic cost. While controlling for prosthetic stiffness (in kilonewtons per meter), using the Flex-Run (β = -0.139; P = 0.044) and 1E90 Sprinter prostheses (β = -0.176; P = 0.009) reduced net metabolic costs by 4.3-4.9% compared with using the Catapult prostheses. The metabolic cost of running improved when athletes used prosthetic configurations that decreased peak horizontal braking ground reaction forces (β = 2.786; P = 0.001), stride frequencies (β = 0.911; P < 0.001), and leg stiffness values (β = 0.053; P = 0.009). Remarkably, athletes did not maintain overall leg stiffness across prosthetic stiffness conditions. Rather, the in-series prosthetic stiffness governed overall leg stiffness. The metabolic cost of running in athletes with bilateral transtibial amputations is influenced by prosthetic model and stiffness but not height. NEW & NOTEWORTHY We measured the

Clinical Effectiveness of Using Aesthetic Fixed Prosthetic Appliances with Combined Occlusal Surface

OpenAIRE

Andrii Biben; Zinovii Ozhohan

2017-01-01

The objective of the research was to evaluate the clinical effectiveness of using aesthetic fixed prosthetic appliances with combined occlusal surface. Materials and methods. The study included 30 patients who were divided into 2 groups: Group I included 20 patients with combined occlusal surface of the crowns; Group II included 22 patients with ceramic occlusal surface of the crowns. The patients were observed 3, 6 and 12 months after prosthetic repair. Results. 6 months after prosthet...

Classification of EMG signals using artificial neural networks for virtual hand prosthesis control.

Science.gov (United States)

Mattioli, Fernando E R; Lamounier, Edgard A; Cardoso, Alexandre; Soares, Alcimar B; Andrade, Adriano O

2011-01-01

Computer-based training systems have been widely studied in the field of human rehabilitation. In health applications, Virtual Reality presents itself as an appropriate tool to simulate training environments without exposing the patients to risks. In particular, virtual prosthetic devices have been used to reduce the great mental effort needed by patients fitted with myoelectric prosthesis, during the training stage. In this paper, the application of Virtual Reality in a hand prosthesis training system is presented. To achieve this, the possibility of exploring Neural Networks in a real-time classification system is discussed. The classification technique used in this work resulted in a 95% success rate when discriminating 4 different hand movements.

Clinical Presentation, Risk Factors, and Outcomes of Hematogenous Prosthetic Joint Infection in Patients with Staphylococcus aureus Bacteremia.

Science.gov (United States)

Tande, Aaron J; Palraj, Bharath Raj; Osmon, Douglas R; Berbari, Elie F; Baddour, Larry M; Lohse, Christine M; Steckelberg, James M; Wilson, Walter R; Sohail, M Rizwan

2016-02-01

Staphylococcus aureus bacteremia is a life-threatening condition that may lead to metastatic infection, including prosthetic joint infection. To assess clinical factors associated with hematogenous prosthetic joint infection, we retrospectively reviewed all patients with a joint arthroplasty in place at the time of a first episode of S. aureus bacteremia over a 5-year period at our institution. Patients with postsurgical prosthetic joint infection without hematogenous prosthetic joint infection were excluded. There were 85 patients (143 arthroplasties) with either no prosthetic joint infection (n = 50; 58.8%) or hematogenous prosthetic joint infection in at least one arthroplasty (n = 35; 41.2%). The odds of hematogenous prosthetic joint infection was significantly increased among patients with community-acquired S. aureus bacteremia (odds ratio [OR] 18.07; 95% confidence interval [CI] 2.64-infinity; P = .001), as compared with nosocomial S. aureus bacteremia, in which there were no patients with hematogenous prosthetic joint infection. After adjusting for S. aureus bacteremia classification, the presence of ≥3 joint arthroplasties in place was associated with a nearly ninefold increased odds of hematogenous prosthetic joint infection as compared with those with 1-2 joint arthroplasties in place (OR 8.55; 95% CI 1.44-95.71; P = .012). All but one joint with prosthetic joint infection demonstrated at least one clinical feature suggestive of infection. There were 4 additional S. aureus prosthetic joint infections diagnosed during a median of 3.4 years of follow-up post hospitalization for S. aureus bacteremia. Prosthetic joint infection is frequent in patients with existing arthroplasties and concomitant S. aureus bacteremia, particularly with community-acquired S. aureus bacteremia and multiple prostheses. In contrast, occult S. aureus prosthetic joint infection without clinical features suggestive of prosthetic joint infection at the time of S. aureus bacteremia

Effects of smartphone overuse on hand function, pinch strength, and the median nerve.

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İnal, Esra Erkol; Demİrcİ, kadİr; Çetİntürk, Azİze; Akgönül, Mehmet; Savaş, Serpİl

2015-08-01

In this study we investigated the flexor pollicis longus (FPL) tendon and median nerve in smartphone users by ultrasonography to assess the effects of smartphone addiction on the clinical and functional status of the hands. One hundred two students were divided into 3 groups: non-users, and high or low smartphone users. Smartphone Addiction Scale (SAS) scores and grip and pinch strengths were recorded. Pain in thumb movement and rest and hand function were evaluated on the visual analog scale (VAS) and the Duruöz Hand Index (DHI), respectively. The cross-sectional areas (CSAs) of the median nerve and the FPL tendon were calculated bilaterally using ultrasonography. Significantly higher median nerve CSAs were observed in the dominant hands of the high smartphone users than in the non-dominant hands (PSmartphone overuse enlarges the median nerve, causes pain in the thumb, and decreases pinch strength and hand functions. © 2015 Wiley Periodicals, Inc.

Clinical characteristics, microbiology, and outcomes of prosthetic joint infection in Taiwan.

Science.gov (United States)

Tsai, Jen-Chih; Sheng, Wang-Huei; Lo, Wan-Yu; Jiang, Ching-Chuan; Chang, Shan-Chwen

2015-04-01

Prosthetic joint infection (PJI) after total knee or hip replacement is a devastating complication associated with substantial morbidity and economic cost. The incidence of prosthetic joint infection is increasing as the use of mechanical joint replacement increases. The treatment approach to prosthetic joint infection is based on different clinical situations such as a patient's comorbidities, epidemic microbiology data, and surgical procedures. The aim of our study was to understand clinical characteristics of prosthetic joint infection, the microbiology of the prosthetic joint infection, and the outcomes of different treatment strategies during 2006-2011. We retrospectively collected cases of prosthetic joint infection in the National Taiwan University Hospital between January 1, 2006 and December 31, 2011. The patients' characteristics, microbiology, outcomes, and factors associated with treatment success were recorded. One hundred and forty-four patients were identified as having PJI. Of these, 92 patients were entered into per-protocol analysis. Staphylococcus aureus was the most common causative organism (29.9%), followed by coagulase-negative Staphylococci (16.7%), and Enterococci (9.7%). The overall treatment success rate was 50%. Patients who received a two-stage revision had a better outcome, compared to patients who underwent other types of surgeries (70% vs. 32.7%, respectively; p < 0.001). In multivariate analysis, the two-stage revision was significantly associated with treatment success (odds ratio = 3.923, 95% confidence interval = 1.53-10.04). Our study demonstrates that Staphylococcus aureus was the most common causative organisms in PJI. Performing two-stage revisions was significantly associated with a better outcome. Copyright © 2013. Published by Elsevier B.V.

Granulicatella adiacens prosthetic hip joint infection after dental treatment.

Science.gov (United States)

Aweid, Osama; Sundararajan, Sabapathy; Teferi, Abraham

2016-06-01

Granulicatella adiacens is a Gram-positive bacteria and a normal component of oral flora. It is also found in dental plaques, endodontic abscesses and can rarely cause more serious infections. We describe a prosthetic hip joint infection in an 81-year-old fit and healthy man due to Granulicatella adiacens who underwent a prolonged dental intervention two days earlier without antibiotic prophylaxis. The infection was successfully treated with surgical intervention and a combination of antibiotics. The patient eventually succumbed to severe community-acquired pneumonia two months later. Current guidelines recommend avoidance of antibiotic prophylaxis prior to dental treatment in patients who have no co-morbidities and no prior operation on the index prosthetic joint. This case report indicates that infections of prosthetic joints may be associated with dental procedures even in fit and healthy patients without the recognized risk factors.

[Tuberculous prosthetic knee joint infection: a case report and literature review].

Science.gov (United States)

Lara-Oya, A; Liébana-Martos, M C; Rodríguez-Granger, J; Sampedro-Martínez, A; Aliaga-Martínez, L; Gutierrez-Fernández, J; Navarro-Marí, J M

2016-08-01

Prosthetic late infection occurs in the second month after surgery in the context of haematogenous spread from another source. Prosthetic mycobacterial infection is a rare complication whose clinical management is not standardized. Patient of 77 years with no personal history except for diabetes and a prosthetic replacement of right knee with osteoarthritis three years ago. Patient goes to hospital emergency box for 6 months pain in the right knee with mechanical inflammatory signs but no fever associated. After their return within 5 days and clinical worsening is reporting growth of Mycobacterium tuberculosis in knee aspirate and antitubercular treatment is established for 9 months. Nuclear magnetic resonance imaging studies also confirmed the diagnosis of tuberculosis spondylitis in the clinical context of the patients. After surgery, M. tuberculosis was again isolated from intraoperative samples and therefore the patient received another batch of treatment for 9 months. After a year of monitoring, the development was acceptable but few months later, the patient died for cardiovascular causes. In the literature review, 15 publications with a total of 17 clinical cases of prosthetic infection by M. tuberculosis were found from 1980 to 2014. Prosthetic tuberculous arthritis, although it is a rare presentation, it should be noted, especially in patients with predisposing conditions with a history of tuberculosis infection.

An implementation of movement classification for prosthesis control using custom-made EMG system

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Mejić Luka

2017-01-01

Full Text Available Electromyography (EMG is a well known technique used for recording electrical activity produced by human muscles. In the last few decades, EMG signals are used as a control input for prosthetic hands. There are several multifunctional myoelectric prosthetic hands for amputees on the market, but so forth, none of these devices permits the natural control of more than two degrees of freedom. In this paper we present our implementation of the pattern classification using custom made components (electrodes and an embedded EMG amplifier. The components were evaluated in offline and online tests, in able bodied as well as amputee subjects. This type of control is based on computing the time domain features of the EMG signals recorded from the forearm and using these features as input for a Linear Discriminant Analysis (LDA classifier estimating the intention of the prosthetic user. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III - 41007

Technical note: Computer-manufactured inserts for prosthetic sockets.

Science.gov (United States)

Sanders, Joan E; McLean, Jake B; Cagle, John C; Gardner, David W; Allyn, Katheryn J

2016-08-01

The objective of this research was to use computer-aided design software and a tabletop 3-D additive manufacturing system to design and fabricate custom plastic inserts for trans-tibial prosthesis users. Shape quality of inserts was tested right after they were inserted into participant's test sockets and again after four weeks of wear. Inserts remained properly positioned and intact throughout testing. Right after insertion the inserts caused the socket to be slightly under-sized, by a mean of 0.11mm, approximately 55% of the thickness of a nylon sheath. After four weeks of wear the under-sizing was less, averaging 0.03mm, approximately 15% of the thickness of a nylon sheath. Thus the inserts settled into the sockets over time. If existing prosthetic design software packages were enhanced to conduct insert design and to automatically generate fabrication files for manufacturing, then computer manufactured inserts may offer advantages over traditional methods in terms of speed of fabrication, ease of design, modification, and record keeping. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

Long-term clinical evaluation of the automatic stance-phase lock-controlled prosthetic knee joint in young adults with unilateral above-knee amputation.

Science.gov (United States)

Andrysek, Jan; Wright, F Virginia; Rotter, Karin; Garcia, Daniela; Valdebenito, Rebeca; Mitchell, Carlos Alvarez; Rozbaczylo, Claudio; Cubillos, Rafael

2017-05-01

The purpose of this study was to clinically evaluate the automatic stance-phase lock (ASPL) knee mechanism against participants' existing weight-activated braking (WAB) prosthetic knee joint. This prospective crossover study involved 10 young adults with an above-knee amputation. Primary measurements consisted of tests of walking speeds and capacity. Heart rate was measured during the six-minute walk test and the Physiological Cost Index (PCI) which was calculated from heart rate estimated energy expenditure. Activity was measured with a pedometer. User function and quality of life were assessed using the Lower Limb Function Questionnaire (LLFQ) and Prosthetic Evaluation Questionnaire (PEQ). Long-term follow-up over 12 months were completed. Walking speeds were the same for WAB and APSL knees. Energy expenditure (PCI) was lower for the ASPL knees (p = 0.007). Step counts were the same for both knees, and questionnaires indicated ASPL knee preference attributed primarily to knee stability and improved walking, while limitations included terminal impact noise. Nine of 10 participants chose to keep using the ASPL knee as part of the long-term follow-up. Potential benefits of the ASPL knee were identified in this study by functional measures, questionnaires and user feedback, but not changes in activity or the PEQ.

Prosthetic valve endocarditis caused by Staphylococcus capitis: report of 4 cases

Directory of Open Access Journals (Sweden)

Wada Yuko

2011-10-01

Full Text Available Abstract Although Staphylococcus capitis is considered to be a rare causative organism for prosthetic valve endocarditis, we report 4 such cases that were encountered at our hospital over the past 2 years. Case 1 was a 79-year-old woman who underwent aortic valve replacement with a bioprosthetic valve and presented with fever 24 days later. Transesophageal echocardiography revealed an annular abscess in the aorto-mitral continuity and mild perivalvular regurgitation. We performed emergency surgery 5 days after the diagnosis of prosthetic valve endocarditis was made. Case 2 was a 79-year-old woman presenting with fever 40 days after aortic valve replacement with a bioprosthesis. Transesophageal echocardiography showed vegetation on the valve, and she underwent urgent surgery 2 days after prosthetic valve endocarditis was diagnosed. In case 3, a 76-year-old man presented with fever 53 days after aortic valve replacement with a bioprosthesis. Vegetation on the prosthetic leaflet could be seen by transesophageal echocardiography. He underwent emergency surgery 2 days after the diagnosis of prosthetic valve endocarditis was made. Case 4 was a 68-year-old woman who collapsed at her home 106 days after aortic and mitral valve replacement with bioprosthetic valves. Percutaneous cardiopulmonary support was started immediately after massive mitral regurgitation due to prosthetic valve detachment was revealed by transesophageal echocardiography. She was transferred to our hospital by helicopter and received surgery immediately on arrival. In all cases, we re-implanted another bioprosthesis after removal of the infected valve and annular debridement. All patients recovered without severe complications after 2 months of antibiotic treatment, and none experienced re-infection during 163 to 630 days of observation. Since the time interval between diagnosis of prosthetic valve endocarditis and valve re-replacement ranged from 0 to 5 days, early surgical removal

LOW-MOLECULAR-WEIGHT HEPARIN TREATMENT FAILURE IN PREVENTION OF PROSTHETIC MITRAL VALVE THROMBOSIS

OpenAIRE

David Šuran; Vojko Kanič; Tatjana Golob Gulič; Husam Franjo Naji; Robert Lipovec

2009-01-01

Background Prosthetic heart valve thrombosis (PHVT) represents a dangerous postoperative complication following prosthetic heart valve replacement. Incidence varies according to different data from 0.5–4 % per year following mitral or aortic valve replacement in spite of adequate oral anticoagulation with coumarins. Case report We are presenting a case of prosthetic mitral valve thrombosis as a result of 6-month lowmolecular-weight heparin (LMWH) (nadroparine) treatment failure. Our pat...

Obtention of a prosthetic group for labelling of radioiodinated proteins

International Nuclear Information System (INIS)

Santos, Josefina da S.; Colturato, Maria Tereza; Araujo, Elaine B. de

2000-01-01

Antibodies and peptides labeled with radionuclides has been extensively used in radioimmunotherapy and radioimmunodetection. The principal problem with the use of radioiodinated proteins is the in vivo dehalogenation. The use of prosthetic groups for indirect labeling of proteins with radioiodine has showed to be useful on labeling proteins with greater in vivo stability. A procedure is described for the preparation of an radioiodinated prosthetic group (N-succinimidyl 4-radioiodine-benzoate-SIB), using procedure described by Stocklin et al, with the iodination of p-bromo-benzoic acid and subsequent reaction with TSTU. Preliminary labeling results showed that the prosthetic group can be obtained in a good yield. The coupling of the SIB to the protein will be studied using human IgG as protein model. (author)

NUI framework based on real-time head pose estimation and hand gesture recognition

Directory of Open Access Journals (Sweden)

Kim Hyunduk

2016-01-01

Full Text Available The natural user interface (NUI is used for the natural motion interface without using device or tool such as mice, keyboards, pens and markers. In this paper, we develop natural user interface framework based on two recognition module. First module is real-time head pose estimation module using random forests and second module is hand gesture recognition module, named Hand gesture Key Emulation Toolkit (HandGKET. Using the head pose estimation module, we can know where the user is looking and what the user’s focus of attention is. Moreover, using the hand gesture recognition module, we can also control the computer using the user’s hand gesture without mouse and keyboard. In proposed framework, the user’s head direction and hand gesture are mapped into mouse and keyboard event, respectively.

A qualitative study of the challenges of providing pre-prosthetic rehabilitation in rural South Africa.

Science.gov (United States)

Ennion, Liezel; Johannesson, Anton

2018-04-01

There is a known shortage of rehabilitation staff in rural settings and a sharp increase in the number of lower limb amputations being performed. A lack of adequate pre-prosthetic rehabilitation will result in worse physical and psychological outcomes for a person with a lower limb amputation, and they will not be eligible to be fitted with a prosthesis. To explore therapists' experiences with providing pre-prosthetic rehabilitation in a rural setting. A qualitative descriptive approach was used to collect and analyse data. Data were collected from 17 purposively sampled therapists in five district hospitals in a rural community in South Africa. Data were collected in two rounds of focus groups to explore the challenges of providing pre-prosthetic rehabilitation in rural South Africa. The main themes identified in the study were (1) a lack of government health system support, (2) poor socioeconomic circumstances of patients and (3) cultural factors that influence rehabilitation. These themes all negatively influence the therapists' ability to follow up patients for pre-prosthetic rehabilitation after discharge from hospital. A lack of adequate pre-prosthetic rehabilitation is a substantial barrier to prosthetic fitting in rural South Africa. Patients who do not receive pre-prosthetic rehabilitation have a poorly shaped residuum or other complications such as knee or hip joint contractures which disqualifies them from being referred to prosthetic services. Therapists involved in this study identified the most important barriers to patients having access to prosthetic services. Clinical relevance Pre-prosthetic rehabilitation provides care of the residuum; maintenance or improvement of physical strength, joint range of motion and referral to a prosthetist. By exploring the challenges known to exist in this service, we can identify potential ways to reduce these barriers and improve the lives of those who use it.

Anaerobic prosthetic joint infection.

Science.gov (United States)

Shah, Neel B; Tande, Aaron J; Patel, Robin; Berbari, Elie F

2015-12-01

In an effort to improve mobility and alleviate pain from degenerative and connective tissue joint disease, an increasing number of individuals are undergoing prosthetic joint replacement in the United States. Joint replacement is a highly effective intervention, resulting in improved quality of life and increased independence [1]. By 2030, it is predicted that approximately 4 million total hip and knee arthroplasties will be performed yearly in the United States [2]. One of the major complications associated with this procedure is prosthetic joint infection (PJI), occurring at a rate of 1-2% [3-7]. In 2011, the Musculoskeletal Infectious Society created a unifying definition for prosthetic joint infection [8]. The following year, the Infectious Disease Society of America published practice guidelines that focused on the diagnosis and management of PJI. These guidelines focused on the management of commonly encountered organisms associated with PJI, including staphylococci, streptococci and select aerobic Gram-negative bacteria. However, with the exception of Propionibacterium acnes, management of other anaerobic organisms was not addressed in these guidelines [1]. Although making up approximately 3-6% of PJI [9,10], anaerobic microorganisms cause devastating complications, and similar to the more common organisms associated with PJI, these bacteria also result in significant morbidity, poor outcomes and increased health-care costs. Data on diagnosis and management of anaerobic PJI is mostly derived from case reports, along with a few cohort studies [3]. There is a paucity of published data outlining factors associated with risks, diagnosis and management of anaerobic PJI. We therefore reviewed available literature on anaerobic PJI by systematically searching the PubMed database, and collected data from secondary searches to determine information on pathogenesis, demographic data, clinical features, diagnosis and management. We focused our search on five commonly

A clinical survey about commercial games in lower limb prosthetic rehabilitation.

Science.gov (United States)

Imam, Bita; Miller, William C; Finlayson, Heather C; Eng, Janice J; Jarus, Tal

2018-06-01

Despite the popularity of commercial games in lower limb prosthetic rehabilitation, data about their prevalence of use as well as therapists' perspectives about these games are still lacking. To learn about the prevalence of use of commercial games in lower limb prosthetic rehabilitation and therapists' perspectives about these games. Cross-sectional. An online survey was sent to physical and occupational therapists across prosthetic rehabilitation facilities in Canada. The survey had questions about the use of commercial games and therapists' perspectives. Data were collected from 82 therapists. Overall, 46.3% (38/82) reported that they use commercial games; of those, 94.7% (36/38) used the Nintendo Wii Fit. The most reported perceived benefits were the Wii Fit helping to improve weight shifting ( n = 76/82, 92.7%) and balance ( n = 75/82, 91.5%), and being motivating and complementing traditional therapy ( n = 75/82, 91.5%). The most reported perceived barriers/challenges were lack of time and familiarity with the games ( n = 58/82, 70.7%). Commercial games, particularly the Wii Fit, are commonly used in lower prosthetic rehabilitation in Canada. Most of the queried therapists view the Wii Fit positively. Knowledge translation activities and developing standard treatment protocols would be helpful in minimizing the barriers identified in this study. Clinical relevance The Wii Fit is prevalent in lower limb prosthetic rehabilitation in Canada and it is viewed positively by therapists as having the potential to improve balance and weight bearing, making rehabilitation more motivating, and complementing traditional therapy. Future studies should investigate the efficacy of the Wii Fit in prosthetic rehabilitation.

Quality Assessment of Prosthetic Rehabilitation Using Aesthetic Fixed Restorations

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Zinovii Ozhohan

2018-04-01

Full Text Available The objective of the research was to study and assess the quality of prosthetic treatment using aesthetic fixed restorations. Materials and methods. The study included 79 patients without a comorbidity who underwent prosthetic rehabilitation. All the patients were divided into 3 groups: Group I included 25 patients with metal-plastic restorations; Group II comprised 34 patients with porcelain-fused-to-metal restorations; Group III consisted of 20 patients with a combined occlusal surface of prosthetic restorations. The patients were observed 6 months after prosthetic repair. Only patients with single molar and premolar crowns were examined. Bridge prostheses were not taken into account in order to eliminate the effect of masticatory force redistribution on the abutment crowns. Results. In Group I, 11 (44% patients were satisfied with the results of prosthetic treatment. In Group II, 25 (78.12% patients reported that they were satisfied with their treatment. In Group III, there were 17 (85% patients satisfied with their outcome. However, the patients’ complaints are often subjective and do not fully reflect the objective state of the dentoalveolar system. An objective examination revealed that in indirect restorations, marginal periodontium pathology is typical. Conclusions. Aesthetic fixed restorations with a combined occlusal surface have demonstrated good clinical results, even at long-term follow-up. Combining positive properties of two different construction materials, namely zirconium dioxide and ceramics, they reduce the risk of complications such as marginal periodontium pathology and chipping along the occlusal surface as well as contribute to minimal abrasion of the occlusal surfaces of the antagonistic teeth. We cannot recommend metal-plastic restorations due to their low clinical effectiveness, poor aesthetic qualities as well as a high level of marginal periodontium pathology.

Augmented robotic device for EVA hand manoeuvres

Science.gov (United States)

Matheson, Eloise; Brooker, Graham

2012-12-01

During extravehicular activities (EVAs), pressurised space suits can lead to difficulties in performing hand manoeuvres and fatigue. This is often the cause of EVAs being terminated early, or taking longer to complete. Assistive robotic gloves can be used to augment the natural motion of a human hand, meaning work can be carried out more efficiently with less stress to the astronaut. Lightweight and low profile solutions must be found in order for the assistive robotic glove to be easily integrated with a space suit pressure garment. Pneumatic muscle actuators combined with force sensors are one such solution. These actuators are extremely light, yet can output high forces using pressurised gases as the actuation drive. Their movement is omnidirectional, so when combined with a flexible exoskeleton that itself provides a degree of freedom of movement, individual fingers can be controlled during flexion and extension. This setup allows actuators and other hardware to be stored remotely on the user's body, resulting in the least possible mass being supported by the hand. Two prototype gloves have been developed at the University of Sydney; prototype I using a fibreglass exoskeleton to provide flexion force, and prototype II using torsion springs to achieve the same result. The gloves have been designed to increase the ease of human movements, rather than to add unnatural ability to the hand. A state space control algorithm has been developed to ensure that human initiated movements are recognised, and calibration methods have been implemented to accommodate the different characteristics of each wearer's hands. For this calibration technique, it was necessary to take into account the natural tremors of the human hand which may have otherwise initiated unexpected control signals. Prototype I was able to actuate the user's hand in 1 degree of freedom (DOF) from full flexion to partial extension, and prototype II actuated a user's finger in 2 DOF with forces achieved

Effect of Modifying Prosthetic Socket Base Materials by Adding Nanodiamonds

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Lifang Ma

2015-01-01

Full Text Available The curing process of prosthetic socket base materials requires attention owing to a series of associated problems that are yet to be addressed and solved. However, to date, few relevant studies have been reported. In this paper, nanodiamonds modified with a silane coupling agent were dispersed into a prosthetic socket base material, and the performance of the modified base materials was investigated. Adding a predetermined amount of nanodiamonds to the prosthetic socket base material increased the glass transition temperature, improved the mechanical properties of the cured base material, and reduced the influence of the volatile gas formed during the curing process on the environment. With increasing nanodiamond contents, the glass transition temperature increased and the mechanical properties improved slightly. Owing to the high thermal conductivity of the nanodiamonds, the localized heat, as a result of the curing process, could be dissipated and released. Thus, adding nanodiamonds led to a more uniform temperature field forming in the curing system. This improved the curing process and reduced the formation of volatile monomers, thereby decreasing the adverse impact of the generated volatile gases on the environment. All of these provide a potential strategy for modifying prosthetic socket base materials.

Strength evaluation of prosthetic check sockets, copolymer sockets, and definitive laminated sockets.

Science.gov (United States)

Gerschutz, Maria J; Haynes, Michael L; Nixon, Derek; Colvin, James M

2012-01-01

A prosthesis encounters loading through forces and torques exerted by the person with amputation. International Organization for Standardization (ISO) standard 10328 was designed to test most lower-limb prosthetic components. However, this standard does not include prosthetic sockets. We measured static failure loads of prosthetic sockets using a modified ISO 10328 and then compared them with the criteria set by this standard for other components. Check socket (CS) strengths were influenced by thickness, material choice, and fabrication method. Copolymer socket (CP) strengths depended on thickness and fabrication methods. A majority of the CSs and all of the CPs failed to pass the ISO 10328 ductile loading criterion. In contrast, the strengths of definitive laminated sockets (DLs) were influenced more by construction material and technique. A majority of the DLs failed to pass the ISO 10328 brittle loading criterion. Analyzing prosthetic sockets from a variety of facilities demonstrated that socket performance varies considerably between and within facilities. The results from this article provide a foundation for understanding the quality of prosthetic sockets, some insight into possible routes for improving the current care delivered to patients, and a comparative basis for future technology.

Computed Tomography of Prosthetic Heart Valves

NARCIS (Netherlands)

Habets, J.

2012-01-01

Prosthetic heart valve (PHV) dysfunction is an infrequent but potentially life-threatening disease with a heterogeneous clinical presentation. Patients with PHV dysfunction clinically can present with symptoms of congestive heart failure (dyspnea, fatigue, edema), fever, angina pectoris, dizziness

Coronary artery assessment by multidetector computed tomography in patients with prosthetic heart valves

International Nuclear Information System (INIS)

Habets, Jesse; Mali, Willem P.T.M.; Budde, Ricardo P.J.; Brink, Renee B.A. van den; Uijlings, Ruben; Spijkerboer, Anje M.; Chamuleau, Steven A.J.

2012-01-01

Patients with prosthetic heart valves may require assessment for coronary artery disease. We assessed whether valve artefacts hamper coronary artery assessment by multidetector CT. ECG-gated or -triggered CT angiograms were selected from our PACS archive based on the presence of prosthetic heart valves. The best systolic and diastolic axial reconstructions were selected for coronary assessment. Each present coronary segment was scored for the presence of valve-related artefacts prohibiting coronary artery assessment. Scoring was performed in consensus by two observers. Eighty-two CT angiograms were performed on a 64-slice (n = 27) or 256-slice (n = 55) multidetector CT. Eighty-nine valves and five annuloplasty rings were present. Forty-three out of 1160 (3.7%) present coronary artery segments were non-diagnostic due to valve artefacts (14/82 patients). Valve artefacts were located in right coronary artery (15/43; 35%), left anterior descending artery (2/43; 5%), circumflex artery (14/43; 32%) and marginal obtuse (12/43; 28%) segments. All cobalt-chrome containing valves caused artefacts prohibiting coronary assessment. Biological and titanium-containing valves did not cause artefacts except for three specific valve types. Most commonly implanted prosthetic heart valves do not hamper coronary assessment on multidetector CT. Cobalt-chrome containing prosthetic heart valves preclude complete coronary artery assessment because of severe valve artefacts. circle Most commonly implanted prosthetic heart valves do not hamper coronary artery assessment circle Prosthetic heart valve composition determines the occurrence of prosthetic heart valve-related artefacts circle Bjoerk-Shiley and Sorin tilting disc valves preclude diagnostic coronary artery segment assessment. (orig.)

The radiology of prosthetic heart valves

International Nuclear Information System (INIS)

Steiner, R.M.; Flicker, S.

1985-01-01

The development of prosthetic heart valves in the late 1950s ushered in a new era in the treatment of heart disease. The radiologist has an important role to play preoperatively in the diagnosis of valvular heart disease. Radiology is valuable in identification of the implanted prosthetic valve and recognition of complications associated with valve implantation. Radiologists must be familiar with the imaging techniques best suited to evaluate the function of the valve prosthesis in question. In this chapter the authors discuss the radiographic approach to the evaluation of the status of patients for valve replacement and the imaging problems peculiar to the types of valves in current use. The relative value of plain-film radiography, fluoroscopy, videorecording and cinerecording, and aortography is addressed, as well as the potential value of magnetic resonance imaging and subsecond dynamic computed tomography

Re-operation for aortic and mitral prosthetic dysfunctions.

Science.gov (United States)

Kaul, T K; Sastry, M R; Mercer, J L; Meade, J B

1985-01-01

The overall incidence of re-operation and prosthetic valve endocarditis was low in the present series as mechanical prostheses were used predominantly. The prosthetic dysfunctions were less frequent following the primary implantation with Bjork Shiley prostheses, but high operative risk was associated with the clotted Bjork Shiley prostheses. We also had unusual experience of strut fracture and sticking of Bjork Shiley discs in the closed position in both aortic and mitral positions. The early deaths were nil since the use of cardioplegic protection. Intra-operative bleeding due to adhesions can be minimised by using synthetic or heterologous pericardium during the primary operation.

GPU accelerated left/right hand-segmentation in first person vision

NARCIS (Netherlands)

Betancourt Arango, A.; Marcenaro, L.; Barakova, E.I.; Rauterberg, M.; Regazzoni, C.S.; Hua, G.; Jegou, H.

2016-01-01

Wearable cameras allow users to record their daily activities from a user-centered (First Person Vision) perspective. Due to their favourable location, they frequently capture the hands of the user, and may thus represent a promising user-machine interaction tool for different applications. Existent

Variable Thumb Moment Arm Modeling and Thumb-Tip Force Production of a Human-Like Robotic Hand.

Science.gov (United States)

Niehues, Taylor D; Deshpande, Ashish D

2017-10-01

The anatomically correct testbed (ACT) hand mechanically simulates the musculoskeletal structure of the fingers and thumb of the human hand. In this work, we analyze the muscle moment arms (MAs) and thumb-tip force vectors in the ACT thumb in order to compare the ACT thumb's mechanical structure to the human thumb. Motion data are used to determine joint angle-dependent MA models, and thumb-tip three-dimensional (3D) force vectors are experimentally analyzed when forces are applied to individual muscles. Results are presented for both a nominal ACT thumb model designed to match human MAs and an adjusted model that more closely replicates human-like thumb-tip forces. The results confirm that the ACT thumb is capable of faithfully representing human musculoskeletal structure and muscle functionality. Using the ACT hand as a physical simulation platform allows us to gain a better understanding of the underlying biomechanical and neuromuscular properties of the human hand to ultimately inform the design and control of robotic and prosthetic hands.

Future Research Opportunities in Peri-Prosthetic Joint Infection Prevention.

Science.gov (United States)

Berbari, Elie; Segreti, John; Parvizi, Javad; Berríos-Torres, Sandra I

Peri-prosthetic joint infection (PJI) is a serious complication of prosthetic joint arthroplasty. A better understanding and reversal of modifiable risk factors may lead to a reduction in the incidence of incisional (superficial and deep) and organ/space (e.g., PJI) surgical site infections (SSI). Recently, the Centers for Disease Control and Prevention (CDC) and the Healthcare Infection Control Practices Advisory Committee (HICPAC) published the Guideline for Prevention of Surgical Site Infection. This targeted update applies evidence-based methodology in drafting recommendations for potential strategies to reduce the risk of SSI both across surgical procedures and specifically in prosthetic joint arthroplasty. A panel of PJI content experts identified nine PJI prevention research opportunities based on both evidence gaps identified through the guideline development process (transfusion, immunosuppressive therapy, anticoagulation, orthopedic space suit, and biofilm) and expert opinion (anesthesia, operative room environment, glycemic control, and Staphylococcus aureus nasal screening and decolonization. This article offers a road map for PJI prevention research.

Experiences of providing prosthetic and orthotic services in Sierra Leone--the local staff's perspective.

Science.gov (United States)

Magnusson, Lina; Ahlström, Gerd

2012-01-01

In Sierra Leone, West Africa, there are many people with disabilities in need of rehabilitation services after a long civil war. The aim of this qualitative study was to explore the experiences of prosthetic and orthotic service delivery in Sierra Leone from the local staff's perspective. Fifteen prosthetic and orthotic technicians working at all the rehabilitation centres providing prosthetic and orthotic services in Sierra Leone were interviewed. The interviews were transcribed and subjected to latent content analysis. One main theme emerged: sense of inability to deliver high-quality prosthetic and orthotic services. This main theme was generated from eight sub-themes: Desire for professional development; appraisals of work satisfaction and norms; patients neglected by family; limited access to the prosthetic and orthotic services available; problems with materials and machines; low public awareness concerning disabilities; marginalisation in society and low priority on the part of government. The findings illustrated traditional beliefs about the causes of disability and that the public's attitude needs to change to include and value people with disabilities. Support from international organisations was considered necessary as well as educating more prosthetic and orthotic staff to a higher level.

Advantages of externally powered prosthesis with feedback system using pseudo-cineplasty.

Science.gov (United States)

Nambu, Seiji; Ikebuchi, Mitsuhiko; Taniguchi, Masashi; Park, Choong Sik; Kitagawa, Takahiro; Nakajima, Shigeyoshi; Koike, Tatsuya

2014-01-01

Externally powered upper-limb prostheses are difficult to use because of the lack of sensory feedback. Neuroprostheses have recently been developed for people with upper-limb amputation but are complicated, expensive, and still developing. We therefore designed a simple system by combining pseudo-cineplasty with extended physiological proprioception to provide sensory feedback to the body. We penetrated the palmaris longus tendon percutaneously with a metal ring, similar to that used in body piercing, in a nondisabled subject as a pseudo-cineplasty. The tendon and ring were connected to the system, and a sensory feedback experiment was performed. We investigated the ability of the user to determine the size of an object grasped by the prosthetic hand without visual information. The subject could distinguish between large and small objects with 100% accuracy and between small, medium, and large objects with 80% accuracy. In pseudo-cineplasty, control and sensory feedback are natural because the prosthetic hand is controlled by muscle contraction. Tension transmitted from the prosthetic hand is sensed via muscle spindles and skin sensors. This technique allows only partial sensory feedback but appears to offer several advantages over other human-machine interfaces.

Capnocytophaga canimorsus: a rare case of conservatively treated prosthetic valve endocarditis.

Science.gov (United States)

Jalava-Karvinen, Päivi; Grönroos, Juha O; Tuunanen, Helena; Kemppainen, Jukka; Oksi, Jarmo; Hohenthal, Ulla

2018-05-01

We describe a rare case of prosthetic valve endocarditis caused by the canine bacterium Capnocytophaga canimorsus in a male aged 73 years. The diagnosis of infective endocarditis was unequivocal, as it blood cultures were positive for C. canimorsus and vegetations were detected on transesophageal echocardiography; the modified Duke criteria were fulfilled. PET-CT showed intense 18 F-FDG uptake of the prosthetic valve area. The patient was treated with antibiotics alone (no surgery), and is now on life-long suppressive antibiotic therapy. To our knowledge, this is the third reported case of prosthetic valve endocarditis caused by C. canimorsus and the first one to have been treated conservatively. © 2018 APMIS. Published by John Wiley & Sons Ltd.

Design and Fabrication of an Instrumented Handrim to Measure the Kinetic and Kinematic Information by the Hand of User for 3D Analysis of Manual Wheelchair Propulsion Dynamics.

Science.gov (United States)

Mallakzadeh, Mohammadreza; Akbari, Hossein

2014-10-01

The repetitious nature of propelling a wheelchair has been associated with the high incidence of injury among manual wheelchair users (MWUs), mainly in the shoulder, elbow and wrist. Recent literature has found a link between handrim biomechanics and risk of injury to the upper extremity. The valid measurement of three-dimensional net joint forces and torques, however, can lead to a better understanding of the mechanisms of injury, the development of prevention techniques, and the reduction of serious injuries to the joints. In this project, an instrumented wheel system was developed to measure the applied loads dynamically by the hand of the user and the angular position of the wheelchair user's hand on the handrim during the propulsion phase. The system is composed of an experimental six-axis load cell, and a wireless eight channel data logger mounted on a wheel hub. The angular position of the wheel is measured by an absolute magnetic encoder. The angular position of the wheelchair user's hand on the handrim during the propulsion phase (ɸ) or point of force application (PFA) is calculated by means of a new-experimental method using 36 pairs of infrared emitter/receiver diodes mounted around the handrim. In this regard, the observed data extracted from an inexperienced able-bodied subject pushed a wheelchair with the instrumented handrim are presented to show the output behavior of the instrumented handrim. The recorded forces and torques were in agreement with previously reported magnitudes. However, this paper can provide readers with some technical insights into possible solutions for measuring the manual wheelchair propulsion biomechanical data.

Mitral Prosthetic Valve Obstruction and Its Complications

Directory of Open Access Journals (Sweden)

Rajesh Rajan

2015-12-01

Full Text Available Prosthetic Valve Obstruction (PVO is a serious complication which is associated with increased morbidity and mortality. This could result from thrombus formation, development of pannus, or a combination of both. Patients with this complication often present with symptoms and signs of heart failure, systemic embolism, acute cardiovascular collapse, and sudden death. Transesophageal echocardiography and cine fluoroscopy play a vital role in diagnosis of this potentially lethal condition. Herein, we reported a 56-year-old male patient who presented with severe heart failure and was found to have obstructed ATS27 bileaflet mitral prosthetic valve. Thrombolysis and redo surgery are two important options for treating this condition although guidelines for choosing between the two are not very definite.

Utilization of penile prosthesis and male incontinence prosthetics in Saudi Arabia

Directory of Open Access Journals (Sweden)

Amjad Alwaal

2017-01-01

Conclusions: There is an increased utilization of penile prosthetics in Saudi Arabia. The private sector performs the majority of penile prosthesis procedures, and most of them are of the semirigid type. The governmental sector is more likely to perform inflatable penile prosthesis and male incontinence device procedures. Male incontinence prosthetics' use is very limited in Saudi Arabia.

Remote transient Lactobacillus animalis bacteremia causing prosthetic hip joint infection: a case report.

Science.gov (United States)

Somayaji, R; Lynch, T; Powell, J N; Gregson, D

2016-11-04

Lactobacillus spp. are uncommon pathogens in immunocompetent hosts, and even rarer causes of prosthetic device infections. A case of chronic hip prosthetic joint infection (PJI) caused by L. animalis is described. This occurred 5 years after a transient bacteremia with the same organism. Whole genome sequencing of both isolates proved this PJI infection resulted from this remote bacteremia. We document that prosthetic joint infections may be a consequence of bacteremia as much as 3 years before the onset of symptoms.

DME Prosthetics Orthotics, and Supplies Fee Schedule

Data.gov (United States)

U.S. Department of Health & Human Services — Durable Medical Equipment, Prosthetics-Orthotics, and Supplies Fee Schedule. The list contains the fee schedule amounts, floors, and ceilings for all procedure codes...

Hand held data collection and monitoring system for nuclear facilities

Science.gov (United States)

Brayton, D.D.; Scharold, P.G.; Thornton, M.W.; Marquez, D.L.

1999-01-26

Apparatus and method is disclosed for a data collection and monitoring system that utilizes a pen based hand held computer unit which has contained therein interaction software that allows the user to review maintenance procedures, collect data, compare data with historical trends and safety limits, and input new information at various collection sites. The system has a means to allow automatic transfer of the collected data to a main computer data base for further review, reporting, and distribution purposes and uploading updated collection and maintenance procedures. The hand held computer has a running to-do list so sample collection and other general tasks, such as housekeeping are automatically scheduled for timely completion. A done list helps users to keep track of all completed tasks. The built-in check list assures that work process will meet the applicable processes and procedures. Users can hand write comments or drawings with an electronic pen that allows the users to directly interface information on the screen. 15 figs.

Hand held data collection and monitoring system for nuclear facilities

International Nuclear Information System (INIS)

Brayton, D.D.; Scharold, P.G.; Thornton, M.W.; Marquez, D.L.

1999-01-01

Apparatus and method is disclosed for a data collection and monitoring system that utilizes a pen based hand held computer unit which has contained therein interaction software that allows the user to review maintenance procedures, collect data, compare data with historical trends and safety limits, and input new information at various collection sites. The system has a means to allow automatic transfer of the collected data to a main computer data base for further review, reporting, and distribution purposes and uploading updated collection and maintenance procedures. The hand held computer has a running to-do list so sample collection and other general tasks, such as housekeeping are automatically scheduled for timely completion. A done list helps users to keep track of all completed tasks. The built-in check list assures that work process will meet the applicable processes and procedures. Users can hand write comments or drawings with an electronic pen that allows the users to directly interface information on the screen. 15 figs

Combining Electromyography and Tactile Myography to Improve Hand and Wrist Activity Detection in Prostheses

Directory of Open Access Journals (Sweden)

Noémie Jaquier

2017-10-01

Full Text Available Despite recent advances in prosthetics and assistive robotics in general, robust simultaneous and proportional control of dexterous prosthetic devices remains an unsolved problem, mainly because of inadequate sensorization. In this paper, we study the application of regression to muscle activity, detected using a flexible tactile sensor recording muscle bulging in the forearm (tactile myography—TMG. The sensor is made of 320 highly sensitive cells organized in an array forming a bracelet. We propose the use of Gaussian process regression to improve the prediction of wrist, hand and single-finger activation, using TMG, surface electromyography (sEMG; the traditional approach in the field, and a combination of the two. We prove the effectiveness of the approach for different levels of activations in a real-time goal-reaching experiment using tactile data. Furthermore, we performed a batch comparison between the different forms of sensorization, using a Gaussian process with different kernel distances.

Prosthetic joint infections: radionuclide state-of-the-art imaging

Energy Technology Data Exchange (ETDEWEB)

Gemmel, Filip [AZ Alma Campus Sijsele, Department of Nuclear Medicine, Sijsele-Damme (Belgium); Wyngaert, Hans van den [AZ Alma Campus Sijsele, Department of Orthopaedic Surgery, Sijsele-Damme (Belgium); Love, Charito [Albert Einstein College of Medicine of Yeshiva University, Division of Nuclear Medicine and Radiology, Bronx, NY (United States); Welling, M.M. [Leiden University Medical Center, Scientist Molecular Imaging, Department of Radiology, Section of Nuclear Medicine C2-203, Leiden (Netherlands); Gemmel, Paul [Ghent University, The Faculty of Economics and Business Administration, Ghent (Belgium); Palestro, Christopher J. [Hofstra North Shore-Long Island Jewish Health System, Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Hempstead, NY (United States)

2012-05-15

Prosthetic joint replacement surgery is performed with increasing frequency. Overall the incidence of prosthetic joint infection (PJI) and subsequently prosthesis revision failure is estimated to be between 1 and 3%. Differentiating infection from aseptic mechanical loosening, which is the most common cause of prosthetic failure, is especially important because of different types of therapeutic management. Despite a thorough patient history, physical examination, multiple diagnostic tests and complex algorithms, differentiating PJI from aseptic loosening remains challenging. Among imaging modalities, radiographs are neither sensitive nor specific and cross-sectional imaging techniques, such as computed tomography and magnetic resonance imaging, are limited by hardware-induced artefacts. Radionuclide imaging reflects functional rather than anatomical changes and is not hampered by the presence of a metallic joint prosthesis. As a result scintigraphy is currently the modality of choice in the investigation of suspected PJI. Unfortunately, there is no true consensus about the gold standard technique since there are several drawbacks and limitations inherent to each modality. Bone scintigraphy (BS) is sensitive for identifying the failed joint replacement, but cannot differentiate between infection and aseptic loosening. Combined bone/gallium scintigraphy (BS/GS) offers modest improvement over BS alone for diagnosing PJI. However, due to a number of drawbacks, BS/GS has generally been superseded by other techniques but it still may have a role in neutropenic patients. Radiolabelled leucocyte scintigraphy remains the gold standard technique for diagnosing neutrophil-mediated processes. It seems to be that combined in vitro labelled leucocyte/bone marrow scintigraphy (LS/BMS), with an accuracy of about 90%, is currently the imaging modality of choice for diagnosing PJI. There are, however, significant limitations using in vitro labelled leucocytes and considerable effort

Prosthetic joint infections: radionuclide state-of-the-art imaging

International Nuclear Information System (INIS)

Gemmel, Filip; Wyngaert, Hans van den; Love, Charito; Welling, M.M.; Gemmel, Paul; Palestro, Christopher J.

2012-01-01

Prosthetic joint replacement surgery is performed with increasing frequency. Overall the incidence of prosthetic joint infection (PJI) and subsequently prosthesis revision failure is estimated to be between 1 and 3%. Differentiating infection from aseptic mechanical loosening, which is the most common cause of prosthetic failure, is especially important because of different types of therapeutic management. Despite a thorough patient history, physical examination, multiple diagnostic tests and complex algorithms, differentiating PJI from aseptic loosening remains challenging. Among imaging modalities, radiographs are neither sensitive nor specific and cross-sectional imaging techniques, such as computed tomography and magnetic resonance imaging, are limited by hardware-induced artefacts. Radionuclide imaging reflects functional rather than anatomical changes and is not hampered by the presence of a metallic joint prosthesis. As a result scintigraphy is currently the modality of choice in the investigation of suspected PJI. Unfortunately, there is no true consensus about the gold standard technique since there are several drawbacks and limitations inherent to each modality. Bone scintigraphy (BS) is sensitive for identifying the failed joint replacement, but cannot differentiate between infection and aseptic loosening. Combined bone/gallium scintigraphy (BS/GS) offers modest improvement over BS alone for diagnosing PJI. However, due to a number of drawbacks, BS/GS has generally been superseded by other techniques but it still may have a role in neutropenic patients. Radiolabelled leucocyte scintigraphy remains the gold standard technique for diagnosing neutrophil-mediated processes. It seems to be that combined in vitro labelled leucocyte/bone marrow scintigraphy (LS/BMS), with an accuracy of about 90%, is currently the imaging modality of choice for diagnosing PJI. There are, however, significant limitations using in vitro labelled leucocytes and considerable effort

Effect of power-assisted hand-rim wheelchair propulsion on shoulder load in experienced wheelchair users: A pilot study with an instrumented wheelchair.

Science.gov (United States)

Kloosterman, Marieke G M; Buurke, Jaap H; de Vries, Wiebe; Van der Woude, Lucas H V; Rietman, Johan S

2015-10-01

This study aims to compare hand-rim and power-assisted hand-rim propulsion on potential risk factors for shoulder overuse injuries: intensity and repetition of shoulder loading and force generation in the extremes of shoulder motion. Eleven experienced hand-rim wheelchair users propelled an instrumented wheelchair on a treadmill while upper-extremity kinematic, kinetic and surface electromyographical data was collected during propulsion with and without power-assist. As a result during power-assisted propulsion the peak resultant force exerted at the hand-rim decreased and was performed with significantly less abduction and internal rotation at the shoulder. At shoulder level the anterior directed force and internal rotation and flexion moments decreased significantly. In addition, posterior and the minimal inferior directed forces and the external rotation moment significantly increased. The stroke angle decreased significantly, as did maximum shoulder flexion, extension, abduction and internal rotation. Stroke-frequency significantly increased. Muscle activation in the anterior deltoid and pectoralis major also decreased significantly. In conclusion, compared to hand-rim propulsion power-assisted propulsion seems effective in reducing potential risk factors of overuse injuries with the highest gain on decreased range of motion of the shoulder joint, lower peak propulsion force on the rim and reduced muscle activity. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

The influence of speed and grade on wheelchair propulsion hand pattern.

Science.gov (United States)

Slowik, Jonathan S; Requejo, Philip S; Mulroy, Sara J; Neptune, Richard R

2015-11-01

The hand pattern used during manual wheelchair propulsion (i.e., full-cycle hand path) can provide insight into an individual's propulsion technique. However, previous analyses of hand patterns have been limited by their focus on a single propulsion condition and reliance on subjective qualitative characterization methods. The purpose of this study was to develop a set of objective quantitative parameters to characterize hand patterns and determine the influence of propulsion speed and grade of incline on the patterns preferred by manual wheelchair users. Kinematic and kinetic data were collected from 170 experienced manual wheelchair users on an ergometer during three conditions: level propulsion at their self-selected speed, level propulsion at their fastest comfortable speed and graded propulsion (8%) at their level self-selected speed. Hand patterns were quantified using a set of objective parameters, and differences across conditions were identified. Increased propulsion speed resulted in a shift away from under-rim hand patterns. Increased grade of incline resulted in the hand remaining near the handrim throughout the cycle. Manual wheelchair users change their hand pattern based on task-specific constraints and goals. Further work is needed to investigate how differences between hand patterns influence upper extremity demand and potentially lead to the development of overuse injuries and pain. Copyright © 2015 Elsevier Ltd. All rights reserved.

Occlusion properties of prosthetic contact lenses for the treatment of amblyopia.

Science.gov (United States)

Collins, Randall S; McChesney, Megan E; McCluer, Craig A; Schatz, Martha P

2008-12-01

The efficacy of opaque contact lenses as occlusion therapy for amblyopia has been established in the literature. Prosthetic contact lenses use similar tints to improve cosmesis in scarred or deformed eyes and may be an alternative in occlusion therapy. To test this idea, we determined the degree of vision penalization elicited by prosthetic contact lenses and their effect on peripheral fusion. We tested 19 CIBA Vision DuraSoft 3 Prosthetic soft contact lenses with varying iris prints, underprints, and opaque pupil sizes in 10 volunteers with best-corrected Snellen distance visual acuity of 20/20 or better in each eye. Snellen visual acuity and peripheral fusion using the Worth 4-Dot test at near were measured on each subject wearing each of the 19 lenses. Results were analyzed with 3-factor analysis of variance. Mean visual acuity through the various lenses ranged from 20/79 to 20/620. Eight lenses allowed preservation of peripheral fusion in 50% or more of the subjects tested. Iris print pattern and opaque pupil size were significant factors in determining visual acuity (p occlusion with prosthetic contact lenses a viable therapy for amblyopia. The degree of penalization can be varied and different iris print patterns and pupil sizes, using peripheral fusion, can be preserved with some lenses. Prosthetic contact lenses can be more cosmetically appealing and more tolerable than other amblyopia treatment modalities. These factors may improve compliance in occlusion therapy.

Gestures in an Intelligent User Interface

Science.gov (United States)

Fikkert, Wim; van der Vet, Paul; Nijholt, Anton

In this chapter we investigated which hand gestures are intuitive to control a large display multimedia interface from a user's perspective. Over the course of two sequential user evaluations, we defined a simple gesture set that allows users to fully control a large display multimedia interface, intuitively. First, we evaluated numerous gesture possibilities for a set of commands that can be issued to the interface. These gestures were selected from literature, science fiction movies, and a previous exploratory study. Second, we implemented a working prototype with which the users could interact with both hands and the preferred hand gestures with 2D and 3D visualizations of biochemical structures. We found that the gestures are influenced to significant extent by the fast paced developments in multimedia interfaces such as the Apple iPhone and the Nintendo Wii and to no lesser degree by decades of experience with the more traditional WIMP-based interfaces.

[Virtual Planning of Prosthetic Treatment of the Orbit].

Science.gov (United States)

Veit, Johannes A; Thierauf, Julia; Egner, Kornelius; Wiggenhauser, Paul Severin; Friedrich, Daniel; Greve, Jens; Schuler, Patrick J; Hoffmann, Thomas K; Schramm, Alexander

2017-06-01

Optimal positioning of bone-anchored implants in the treatment of patients with orbital prosthesis is challenging. The definition of implant axis as well as the positioning of the implants is important to prevent failures in prosthetic rehabilitation in these patients. We performed virtual planning of enossal implants at a base of a standard fan beam CT scan using the software CoDiagnostiX™ (DentalWings, Montréal, Canada). By 3D-printing a surgical guide for drilling and implant insertion was manufactured (Med-610™, Stratasys, Rehovot, Israel). An orbital exenteration was performed in a patient after shrinkage of the eyelids 20 years after enucleation and radiation of the orbit due to rhabdomyosarcoma. 4 Vistafix-3 implants (Cochlear™, Cochlea, Centennial, USA) were primarily inserted after resection with the help of the 3D-surgical guide. Prosthetic rehabilitation could be achieved as preplanned to a predictable result. The individual prosthesis of the orbit showed good functional and esthetic outcome. The virtual 3D-planning of endosseous implants for prosthetic orbital and periorbital reconstruction is easy to use and facilitates optimal placement of implants especially in posttherapeutically altered anatomic situations. © Georg Thieme Verlag KG Stuttgart · New York.

Prosthetic Hip Loosening Due to Brucellar Infection: Case Report and Literature Review

Directory of Open Access Journals (Sweden)

Anis Tebourbi

2016-12-01

Full Text Available Context: Brucellosis is actually considered to be the commonest zoonotic infection worldwide; conversely prosthetic infection due to brucella is extremely rare. Although diagnostic is easily achieved, management of such situations is extremely challenging. Aims: To report the case of prosthetic hip loosening due to brucellar infection, discuss management manners and to summarize data about 19 cases reported in the literature. Methods: We report the case of a 73-year-old woman with brucellar prosthetic hip loosening treated with 2-stage exchange of the prosthesis and prolonged double antibiotherapy Results: At two years follow up the patient is pain free with total functional recovery and no clinical and radiographic signs of prosthetic loosening Conclusions: Brucella should be evocated as a cause of total joint arthroplasty infection especially in patients from endemic regions and with occupational exposure. Antibiotic treatment alone can be followed if there are no signs of implant loosening. Tow stage revision should be considered in other cases.

Custom-made silicone hand prosthesis: A case study.

Science.gov (United States)

Nayak, S; Lenka, P K; Equebal, A; Biswas, A

2016-09-01

Up to now, a cosmetic glove was the most common method for managing transmetacarpal (TMC) and carpometacarpal (CMC) amputations, but it is devoid of markings and body color. At this amputation level, it is very difficult to fit a functional prosthesis because of the short available length, unsightly shape, grafted skin, contracture and lack of functional prosthetic options. A 30-year-old male came to our clinic with amputation at the 1st to 4th carpometacarpal level and a 5th metacarpal that was projected laterally and fused with the carpal bone. The stump had grafted skin, redness, and an unhealed suture line. He complained of pain projected over the metacarpal and suture area. The clinical team members decided to fabricate a custom-made silicone hand prosthesis to accommodate the stump, protect the grafted skin, improve the hand's appearance and provide some passive function. The custom silicone hand prosthesis was fabricated with modified flexible wires to provide passive interphalangeal movement. Basic training, care and maintenance instructions for the prosthesis were given to the patient. The silicone hand prosthesis was able to restore the appearance of the lost digits and provide some passive function. His pain (VAS score) was reduced. Improvement in activities of daily living was found in the DASH questionnaire and Jebsen-Taylor Hand Function test. A silicone glove is a good option for more distal amputations, as it can accommodate any deformity, protect the skin, enhance the appearance and provide functional assistance. This case study provides a simple method to get passively movable fingers after proximal hand amputation. Copyright © 2016. Published by Elsevier Masson SAS.

Sensor fusion and computer vision for context-aware control of a multi degree-of-freedom prosthesis.

Science.gov (United States)

Markovic, Marko; Dosen, Strahinja; Popovic, Dejan; Graimann, Bernhard; Farina, Dario

2015-12-01

Myoelectric activity volitionally generated by the user is often used for controlling hand prostheses in order to replicate the synergistic actions of muscles in healthy humans during grasping. Muscle synergies in healthy humans are based on the integration of visual perception, heuristics and proprioception. Here, we demonstrate how sensor fusion that combines artificial vision and proprioceptive information with the high-level processing characteristics of biological systems can be effectively used in transradial prosthesis control. We developed a novel context- and user-aware prosthesis (CASP) controller integrating computer vision and inertial sensing with myoelectric activity in order to achieve semi-autonomous and reactive control of a prosthetic hand. The presented method semi-automatically provides simultaneous and proportional control of multiple degrees-of-freedom (DOFs), thus decreasing overall physical effort while retaining full user control. The system was compared against the major commercial state-of-the art myoelectric control system in ten able-bodied and one amputee subject. All subjects used transradial prosthesis with an active wrist to grasp objects typically associated with activities of daily living. The CASP significantly outperformed the myoelectric interface when controlling all of the prosthesis DOF. However, when tested with less complex prosthetic system (smaller number of DOF), the CASP was slower but resulted with reaching motions that contained less compensatory movements. Another important finding is that the CASP system required minimal user adaptation and training. The CASP constitutes a substantial improvement for the control of multi-DOF prostheses. The application of the CASP will have a significant impact when translated to real-life scenarious, particularly with respect to improving the usability and acceptance of highly complex systems (e.g., full prosthetic arms) by amputees.

New frontiers in the rubber hand experiment: when a robotic hand becomes one's own.

Science.gov (United States)

Caspar, Emilie A; De Beir, Albert; Magalhaes De Saldanha Da Gama, Pedro A; Yernaux, Florence; Cleeremans, Axel; Vanderborght, Bram

2015-09-01

The rubber hand illusion is an experimental paradigm in which participants consider a fake hand to be part of their body. This paradigm has been used in many domains of psychology (i.e., research on pain, body ownership, agency) and is of clinical importance. The classic rubber hand paradigm nevertheless suffers from limitations, such as the absence of active motion or the reliance on approximate measurements, which makes strict experimental conditions difficult to obtain. Here, we report on the development of a novel technology-a robotic, user- and computer-controllable hand-that addresses many of the limitations associated with the classic rubber hand paradigm. Because participants can actively control the robotic hand, the device affords higher realism and authenticity. Our robotic hand has a comparatively low cost and opens up novel and innovative methods. In order to validate the robotic hand, we have carried out three experiments. The first two studies were based on previous research using the rubber hand, while the third was specific to the robotic hand. We measured both sense of agency and ownership. Overall, results show that participants experienced a "robotic hand illusion" in the baseline conditions. Furthermore, we also replicated previous results about agency and ownership.

User certification of hand-held x-ray tube based analytical fluorescent devices in a canadian context

International Nuclear Information System (INIS)

Maharaj, H.P.

2005-01-01

Safety education aims to reduce personal injury and improve well being. This health promotion principle is applied in the case of hand-held open beam x-ray tube based analytical x-ray devices. Such devices not only are light weight and portable, but also present high radiation exposure levels at the beam exit port and potentially can be used in a variety of industrial applications for determination of material composition. There is much potential for radiation risks to occur with resultant adverse effects if such devices are not used by trained individuals within controlled environments. A level of radiation safety knowledge and understanding of the device design, construction and performance characteristics appear warranted. To reduce radiation risks, user certification at a federal level was introduced in 2004 based on International Standards Organization 20807, since that standard comprises elements commensurate with risk reduction strategies. Within these contexts, a federally certified user is deemed to have acquired a level of safety knowledge and skills to facilitate safe use of the device. Certification, however, does not absolve the holder from obligations of compliance with applicable provincial, territorial or federal laws respecting device operation. The union of federal certification and applicable legislative mandated operational criteria reduces radiation risks overall. (author)

A new prosthetic alignment device to read and record prosthesis alignment data.

Science.gov (United States)

Pirouzi, Gholamhossein; Abu Osman, Noor Azuan; Ali, Sadeeq; Davoodi Makinejad, Majid

2017-12-01

Prosthetic alignment is an essential process to rehabilitate patients with amputations. This study presents, for the first time, an invented device to read and record prosthesis alignment data. The digital device consists of seven main parts: the trigger, internal shaft, shell, sensor adjustment button, digital display, sliding shell, and tip. The alignment data were read and recorded by the user or a computer to replicate prosthesis adjustment for future use or examine the sequence of changes in alignment and its effect on the posture of the patient. Alignment data were recorded at the anterior/posterior and medial/lateral positions for five patients. Results show the high level of confidence to record alignment data and replicate adjustments. Therefore, the device helps patients readjust their prosthesis by themselves, or prosthetists to perform adjustment for patients and analyze the effects of malalignment.

Effects of Dexterity Level and Hand Anthropometric Dimensions on Smartphone Users’ Satisfaction

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N. Firat Ozkan

2015-01-01

Full Text Available The usage of smartphones instead of simple mobile phones increases sharply in our era, especially among young people, because they do multiple tasks with single equipment. This study mainly focuses on smartphone satisfaction by combining hand measurements, smartphone users’ survey results, and hand dexterity levels of corresponding users acquired from Minnesota Manual Dexterity Test (MMDT. Structural Equation Modelling (SEM is used as a statistical tool to discover the potential direct and indirect relations among user satisfaction, hand dimensions, and dexterity scores. Results indicates that thumb length, hand length, and dexterity level of the users have notable effects on users’ satisfaction with smartphones. Based on the results, a new approach that includes both gross motor skills and physical measurements is suggested to see hidden indirect relations with satisfaction.

Remote transient Lactobacillus animalis bacteremia causing prosthetic hip joint infection: a case report

Directory of Open Access Journals (Sweden)

R. Somayaji

2016-11-01

Full Text Available Abstract Background Lactobacillus spp. are uncommon pathogens in immunocompetent hosts, and even rarer causes of prosthetic device infections. Case presentation A case of chronic hip prosthetic joint infection (PJI caused by L. animalis is described. This occurred 5 years after a transient bacteremia with the same organism. Whole genome sequencing of both isolates proved this PJI infection resulted from this remote bacteremia. Conclusions We document that prosthetic joint infections may be a consequence of bacteremia as much as 3 years before the onset of symptoms.

Contactless and pose invariant biometric identification using hand surface.

Science.gov (United States)

Kanhangad, Vivek; Kumar, Ajay; Zhang, David

2011-05-01

This paper presents a novel approach for hand matching that achieves significantly improved performance even in the presence of large hand pose variations. The proposed method utilizes a 3-D digitizer to simultaneously acquire intensity and range images of the user's hand presented to the system in an arbitrary pose. The approach involves determination of the orientation of the hand in 3-D space followed by pose normalization of the acquired 3-D and 2-D hand images. Multimodal (2-D as well as 3-D) palmprint and hand geometry features, which are simultaneously extracted from the user's pose normalized textured 3-D hand, are used for matching. Individual matching scores are then combined using a new dynamic fusion strategy. Our experimental results on the database of 114 subjects with significant pose variations yielded encouraging results. Consistent (across various hand features considered) performance improvement achieved with the pose correction demonstrates the usefulness of the proposed approach for hand based biometric systems with unconstrained and contact-free imaging. The experimental results also suggest that the dynamic fusion approach employed in this work helps to achieve performance improvement of 60% (in terms of EER) over the case when matching scores are combined using the weighted sum rule.

In vitro adherence of bacteria to prosthetic grafting materials

International Nuclear Information System (INIS)

Brewer, A.R.; Stromberg, B.V.

1990-01-01

Adherence of bacteria to prosthetic grafting material is thought to play an important role in the ultimate development of prosthetic infections. To evaluate the role of bacterial adherence in the initiation and colonization of prosthetic materials, Proplast II, Gore-Tex, and silicone were evaluated for adherence of Escherichia coli and Staphylococcus aureus. Bacteria were radiolabeled and incubated with the study material. Adherence was determined by scintillation. Adherence to Proplast II and Gore-Tex reached a maximum at approximately 45 minutes of incubation and demonstrated a detachment phenomenon with E. coli. Similar results were noted with S. aureus, but with a maximal attachment at approximately 30 minutes. Interestingly, bacterial attachment to silicone continued to increase throughout the time of the incubation. In addition, adherence of S. aureus was at a faster rate than E. coli. Attachment of bacteria is a multifactorial process. However, the PTFE graft demonstrates a slower rate of attachment, lower total number of attached bacteria, and faster detachment. The importance of this phenomenon may help explain the foreign body effect of increased susceptibility to infection of foreign materials

Exophiala (Wangiella dermatitidis Prosthetic Aortic Valve Endocarditis and Prosthetic Graft Infection in an Immune Competent Patient

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Jay S. Berger

2017-01-01

Full Text Available Exophiala (Wangiella dermatitidis is an emerging dematiaceous fungus associated with high mortality rates and is a rare cause of endocarditis. We describe the first case of E. dermatitidis endocarditis of a prosthetic aortic valve and aortic graft in an immune competent patient with no clear risk factors of hematological acquisition.

Combined computed tomography and fluorodeoxyglucose positron emission tomography in the diagnosis of prosthetic valve endocarditis: a case series.

Science.gov (United States)

Bartoletti, Michele; Tumietto, Fabio; Fasulo, Giovanni; Giannella, Maddalena; Cristini, Francesco; Bonfiglioli, Rachele; Raumer, Luigi; Nanni, Cristina; Sanfilippo, Silvia; Di Eusanio, Marco; Scotton, Pier Giorgio; Graziosi, Maddalena; Rapezzi, Claudio; Fanti, Stefano; Viale, Pierluigi

2014-01-13

The diagnosis of prosthetic valve endocarditis is challenging. The gold standard for prosthetic valve endocarditis diagnosis is trans-esophageal echocardiography. However, trans-esophageal echocardiography may result in negative findings or yield images difficult to differentiate from thrombus in patients with prosthetic valve endocarditis. Combined computed tomography and fluorodeoxyglucose positron emission tomography is a potentially promising diagnostic tool for several infectious conditions and it has also been employed in patients with prosthetic valve endocarditis but data are still scant. We reviewed the charts of 6 patients with prosthetic aortic valves evaluated for suspicion of prosthetic valve endocarditis, at two different hospital, over a 3-year period. We found 3 patients with early-onset PVE cases and blood cultures yielding Pseudomonas aeruginosa, Staphylococcus epidermidis and Staphylococcus lugdunensis, respectively; and 3 late-onset cases in the remaining 3 patients with isolation in the blood of Streptococcus bovis, Candida albicans and P. aeruginosa, respectively. Initial trans-esophageal echocardiography was negative in all the patients, while fluorodeoxyglucose positron emission tomography showed images suspicious for prosthetic valve endocarditis. In 4 out of 6 patients valve replacement was done with histology confirming the prosthetic valve endocarditis diagnosis. After an adequate course of antibiotic therapy fluorodeoxyglucose positron emission tomography showed resolution of prosthetic valve endocarditis in all the patients. Our experience confirms the potential role of fluoroseoxyglucose positron emission tomography in the diagnosis and follow-up of prosthetic valve endocarditis.

Design and Fabrication of an Instrumented Handrim to Measure the Kinetic and Kinematic Information by the Hand of User for 3D Analysis of Manual Wheelchair Propulsion Dynamics

Science.gov (United States)

Mallakzadeh, Mohammadreza; Akbari, Hossein

2014-01-01

The repetitious nature of propelling a wheelchair has been associated with the high incidence of injury among manual wheelchair users (MWUs), mainly in the shoulder, elbow and wrist. Recent literature has found a link between handrim biomechanics and risk of injury to the upper extremity. The valid measurement of three-dimensional net joint forces and torques, however, can lead to a better understanding of the mechanisms of injury, the development of prevention techniques, and the reduction of serious injuries to the joints. In this project, an instrumented wheel system was developed to measure the applied loads dynamically by the hand of the user and the angular position of the wheelchair user's hand on the handrim during the propulsion phase. The system is composed of an experimental six-axis load cell, and a wireless eight channel data logger mounted on a wheel hub. The angular position of the wheel is measured by an absolute magnetic encoder. The angular position of the wheelchair user's hand on the handrim during the propulsion phase (ɸ) or point of force application (PFA) is calculated by means of a new-experimental method using 36 pairs of infrared emitter/receiver diodes mounted around the handrim. In this regard, the observed data extracted from an inexperienced able-bodied subject pushed a wheelchair with the instrumented handrim are presented to show the output behavior of the instrumented handrim. The recorded forces and torques were in agreement with previously reported magnitudes. However, this paper can provide readers with some technical insights into possible solutions for measuring the manual wheelchair propulsion biomechanical data. PMID:25426429

Diagnostic performance of FDG PET or PET/CT in prosthetic infection after arthroplasty: a meta-analysis

International Nuclear Information System (INIS)

Jin, H.; Yuan, L.; Li, C.; Kan, Y.; Yang, J.; Hao, R.

2014-01-01

The purpose of this study was to systematically review and perform a meta-analysis of published data regarding the diagnostic performance of positron emission tomography (PET) or PET/computed tomography (PET/CT) in prosthetic infection after arthroplasty. A comprehensive computer literature search of studies published through May 31, 2012 regarding PET or PET/CT in patients suspicious of prosthetic infection was performed in PubMed/MEDLINE, Embase and Scopus databases. Pooled sensitivity and specificity of PET or PET/CT in patients suspicious of prosthetic infection on a per prosthesis-based analysis were calculated. The area under the receiver-operating characteristic (ROC) curve was calculated to measure the accuracy of PET or PET/CT in patients with suspicious of prosthetic infection. Fourteen studies comprising 838 prosthesis with suspicious of prosthetic infection after arthroplasty were included in this meta-analysis. The pooled sensitivity of PET or PET/CT in detecting prosthetic infection was 86% (95% confidence interval [CI] 82-90%) on a per prosthesis-based analysis. The pooled specificity of PET or PET/CT in detecting prosthetic infection was 86% (95% CI 83-89%) on a per prosthesis-based analysis. The area under the ROC curve was 0.93 on a per prosthesis-based analysis. In patients suspicious of prosthetic infection, FDG PET or PET/CT demonstrated high sensitivity and specificity. FDG PET or PET/CT are accurate methods in this setting. Nevertheless, possible sources of false positive results and influcing factors should kept in mind.

Diagnostic performance of FDG PET or PET/CT in prosthetic infection after arthroplasty: a meta-analysis.

Science.gov (United States)

Jin, H; Yuan, L; Li, C; Kan, Y; Hao, R; Yang, J

2014-03-01

The purpose of this study was to systematically review and perform a meta-analysis of published data regarding the diagnostic performance of positron emission tomography (PET) or PET/computed tomography (PET/CT) in prosthetic infection after arthroplasty. A comprehensive computer literature search of studies published through May 31, 2012 regarding PET or PET/CT in patients suspicious of prosthetic infection was performed in PubMed/MEDLINE, Embase and Scopus databases. Pooled sensitivity and specificity of PET or PET/CT in patients suspicious of prosthetic infection on a per prosthesis-based analysis were calculated. The area under the receiver-operating characteristic (ROC) curve was calculated to measure the accuracy of PET or PET/CT in patients with suspicious of prosthetic infection. Fourteen studies comprising 838 prosthesis with suspicious of prosthetic infection after arthroplasty were included in this meta-analysis. The pooled sensitivity of PET or PET/CT in detecting prosthetic infection was 86% (95% confidence interval [CI] 82-90%) on a per prosthesis-based analysis. The pooled specificity of PET or PET/CT in detecting prosthetic infection was 86% (95% CI 83-89%) on a per prosthesis-based analysis. The area under the ROC curve was 0.93 on a per prosthesis-based analysis. In patients suspicious of prosthetic infection, FDG PET or PET/CT demonstrated high sensitivity and specificity. FDG PET or PET/CT are accurate methods in this setting. Nevertheless, possible sources of false positive results and influcing factors should kept in mind.

Rapidly growing non-tuberculous mycobacteria infection of prosthetic knee joints: A report of two cases.

Science.gov (United States)

Kim, Manyoung; Ha, Chul-Won; Jang, Jae Won; Park, Yong-Beom

2017-08-01

Non-tuberculous mycobacteria (NTM) cause prosthetic knee joint infections in rare cases. Infections with rapidly growing non-tuberculous mycobacteria (RGNTM) are difficult to treat due to their aggressive clinical behavior and resistance to antibiotics. Infections of a prosthetic knee joint by RGNTM have rarely been reported. A standard of treatment has not yet been established because of the rarity of the condition. In previous reports, diagnoses of RGNTM infections in prosthetic knee joints took a long time to reach because the condition was not suspected, due to its rarity. In addition, it is difficult to identify RGNTM in the lab because special identification tests are needed. In previous reports, after treatment for RGNTM prosthetic infections, knee prostheses could not be re-implanted in all cases but one, resulting in arthrodesis or resection arthroplasty; this was most likely due to the aggressiveness of these organisms. In the present report, two cases of prosthetic knee joint infection caused by RGNTM (Mycobacterium abscessus) are described that were successfully treated, and in which prosthetic joints were finally reimplanted in two-stage revision surgery. Copyright © 2017 Elsevier B.V. All rights reserved.

Dutch evidence-based guidelines for amputation and prosthetics of the lower extremity : Rehabilitation process and prosthetics. Part 2

NARCIS (Netherlands)

Geertzen, Jan; van der Linde, Harmen; Rosenbrand, Kitty; Conradi, Marcel; Deckers, Jos; Koning, Jan; Rietman, Hans S.; van der Schaaf, Dick; van der Ploeg, Rein; Schapendonk, Johannes; Schrier, Ernst; Duijzentkunst, Rob Smit; Spruit-van Eijk, Monica; Versteegen, Gerbrig; Voesten, Harrie

2015-01-01

Background: A structured, multidisciplinary approach in the rehabilitation process after amputation is needed that includes a greater focus on the involvement of both (para)medics and prosthetists. There is considerable variation in prosthetic prescription concerning the moment of initial prosthesis

Quality of life after maxillectomy and prosthetic obturator rehabilitation.

Science.gov (United States)

Chigurupati, Radhika; Aloor, Neelam; Salas, Richard; Schmidt, Brian L

2013-08-01

Surgical resection of midface neoplasms and subsequent reconstruction have been shown to have significant negative effects on quality of life (QOL). The purpose of this pilot study was to assess individuals' health-related QOL after maxillectomy and reconstruction with a prosthetic obturator. The QOL of 25 of 43 patients who underwent maxillectomy and prosthetic obturator reconstruction at the University of California-San Francisco was assessed using 3 questionnaires: University of Washington Quality of Life version 4 (UWQOL), Obturator Functioning Scale (OFS), and Mental Health Inventory (MHI). The response rate to the QOL questionnaires was 92% (23 of 25 patients). Time elapsed from maxillectomy and prosthetic obturator reconstruction to the QOL survey response ranged from 0.3 to 6.6 years (mean, 2.7 years; standard deviation [SD], 1.9 years). The post-treatment mean QOL scores were 77.3 (SD, 13.6) for UWQOL, 72.0 (SD, 12.6) for OFS, and 4.5 (SD, 0.9) for Mental Health Inventory. Individuals who received adjuvant radiation scored lower for speech and appearance (OFS, P = .05, P = .03, respectively) as well as for saliva and overall QOL (UWQOL, P = .02, P = .08, respectively). There was a strong correlation between QOL scores in OFS and UWQOL questionnaires (r = 0.78, P maxillectomy and prosthetic obturator reconstruction. There is further need for a multicenter trial with a larger sample to identify how factors affecting QOL of patients after maxillectomy might influence the choice of reconstruction. Copyright © 2013 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

A Statistical Perspective on Running with Prosthetic Lower-Limbs: An Advantage or Disadvantage?

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Hossein Hassani

2014-11-01

Full Text Available Technological developments have led to the increased use of carbon fiber and prosthetic lower-limbs in running events at the Paralympic Games. This study aims to exploit a series of statistical techniques in order to prepare a response to the vital question of whether utilizing prosthetic feet can affect an athletes ability when running competitively at the Paralympics Games by comparing both within and between different classifications. The study also considers the differences between running on biological limbs and prosthetic lower-limbs from a mechanical point of view. The results from the male 100 m, 200 m and 400 m at the 2012 London Paralympic Games have been the source of this investigation. The investigation provides statistical evidence to propose that the number of prosthetic limbs used and the structure of such limbs have a significant impact on the outcome of track events at the Paralympic Games.

Diagnostic flowcharts in osteomyelitis, spondylodiscitis and prosthetic joint infection

International Nuclear Information System (INIS)

Jutte, P.; Lazzeri, E.; Sconfienza, L. M.; Cassar-Pullicino, V.; Trampuz, A.; Petrosillo, N.; Signore, A.

2014-01-01

Infections of the bone, spine and prosthetic joints are serious and complex conditions to diagnose and to treat. Structured diagnostic workup may very well improve the accuracy and speed of diagnosis, thereby improving the outcome since treatment may very well be more successful and less harmful if timely management is started. Literature shows no uniform advise on diagnosis. The EANM organized a consensus meeting with representatives from the involved disciplines in order to develop common flowcharts for the diagnosis of osteomyelitis, spondylodiscitis and prosthetic joint infections. In this report the proceedings of this consensus meeting, including the proposed flowcharts for diagnosis, are published.

Mobility function of a prosthetic knee joint with an automatic stance phase lock.

Science.gov (United States)

Andrysek, Jan; Klejman, Susan; Torres-Moreno, Ricardo; Heim, Winfried; Steinnagel, Bryan; Glasford, Shane

2011-06-01

There is a need for a prosthetic knee joint design that is technologically and functionally appropriate for use in developing countries. To develop and clinically evaluate a new type of stance phase controlled prosthetic knee joint that provides stance phase stability without inhibiting swing phase flexion. A crossover repeated measures study design comparing the new knee joint to the participant's conventional low- or high-end prosthetic knee joint. The new knee joint was fitted to fourteen individuals aged 15 to 67 years with unilateral lower limb amputations. Walk tests were performed to measure walking speed. Energy expenditure was estimated using the physiological cost index (PCI). Walking speeds with the new knee joint were on average 0.14 m/s faster than conventional low-end knees (p < 0.0001), but 0.07 m/s slower than conventional high-end prosthetic knees (p = 0.008). The PCI was similar across all three knee joint technologies (p = 0.276). Mobility function with the new knee joint, in terms of walking speed, was more closely matched to high-end than low-end prosthetic knee joints. Therefore, given its relatively simple design, the new stance phase control mechanism may offer a functional and cost effective solution for active transfemoral amputees. This paper describes a new type of prosthetic knee joint mechanism that is intended to be cost-effective while providing high-level stance phase function to active individuals with a transfemoral amputation. Initial clinical testing suggests that the new knee joint may have some functional advantages over existing technologies in this category.

Design and validation of a morphing myoelectric hand posture controller based on principal component analysis of human grasping.

Science.gov (United States)

Segil, Jacob L; Weir, Richard F ff

2014-03-01

An ideal myoelectric prosthetic hand should have the ability to continuously morph between any posture like an anatomical hand. This paper describes the design and validation of a morphing myoelectric hand controller based on principal component analysis of human grasping. The controller commands continuously morphing hand postures including functional grasps using between two and four surface electromyography (EMG) electrodes pairs. Four unique maps were developed to transform the EMG control signals in the principal component domain. A preliminary validation experiment was performed by 10 nonamputee subjects to determine the map with highest performance. The subjects used the myoelectric controller to morph a virtual hand between functional grasps in a series of randomized trials. The number of joints controlled accurately was evaluated to characterize the performance of each map. Additional metrics were studied including completion rate, time to completion, and path efficiency. The highest performing map controlled over 13 out of 15 joints accurately.

Virtual hand: a 3D tactile interface to virtual environments

Science.gov (United States)

Rogowitz, Bernice E.; Borrel, Paul

2008-02-01

We introduce a novel system that allows users to experience the sensation of touch in a computer graphics environment. In this system, the user places his/her hand on an array of pins, which is moved about space on a 6 degree-of-freedom robot arm. The surface of the pins defines a surface in the virtual world. This "virtual hand" can move about the virtual world. When the virtual hand encounters an object in the virtual world, the heights of the pins are adjusted so that they represent the object's shape, surface, and texture. A control system integrates pin and robot arm motions to transmit information about objects in the computer graphics world to the user. It also allows the user to edit, change and move the virtual objects, shapes and textures. This system provides a general framework for touching, manipulating, and modifying objects in a 3-D computer graphics environment, which may be useful in a wide range of applications, including computer games, computer aided design systems, and immersive virtual worlds.

Restoring natural sensory feedback in real-time bidirectional hand prostheses

DEFF Research Database (Denmark)

Raspopovic, Stanisa; Capogrosso, Marco; Petrini, Francesco Maria

2014-01-01

Hand loss is a highly disabling event that markedly affects the quality of life. To achieve a close to natural replacement for the lost hand, the user should be provided with the rich sensations that we naturally perceive when grasping or manipulating an object. Ideal bidirectional hand prosthese...

A global perspective on mechanical prosthetic heart valve thrombosis: Diagnostic and therapeutic challenges

Science.gov (United States)

Gürsoy, Mustafa Ozan; Kalçık, Macit; Yesin, Mahmut; Karakoyun, Süleyman; Bayam, Emrah; Gündüz, Sabahattin; Özkan, Mehmet

2016-01-01

Prosthetic valve thrombosis is one of the major causes of primary valve failure, which can be life-threatening. Multimodality imaging is necessary for determination of leaflet immobilization, cause of underlying pathology (thrombus versus pannus or both), and whether thrombolytic therapy attempt in the patient would be successful or surgery is needed. Current guidelines for the management of prosthetic valve thrombosis lack definitive class I recommendations due to lack of randomized controlled trials, and usually leave the choice of treatment to the clinician’s experience. In this review, we aimed to summarize the pathogenesis, diagnosis, and management of mechanical prosthetic valve thrombosis. PMID:28005024

Echocardiographic Evaluation of Tricuspid Prosthetic Valves: An Update

Directory of Open Access Journals (Sweden)

Dimitrios Maragiannis, MD, FASE, FACC

2016-05-01

Full Text Available This review focuses on the diagnostic value of novel echocardiographic techniques and the clinical application of recently described algorithms to assess tricuspid prosthetic valve function.

Prosthetic hip joint infection due to Campylobacter fetus.

OpenAIRE

Bates, C J; Clarke, T C; Spencer, R C

1994-01-01

A case of postoperative prosthetic hip joint infection due to Campylobacter fetus subsp. fetus is described. Difficulties in isolation and antimicrobial susceptibility testing of this organism are discussed.

Finite element analysis of the contact interface between trans-femoral stump and prosthetic socket.

Science.gov (United States)

Zhang, Linlin; Zhu, Ming; Shen, Ling; Zheng, Feng

2013-01-01

Transfemoral amputees need prosthetic devices after amputation surgery, and the interface pressure between the residual limb and prosthetic socket has a significant effect on an amputee's satisfaction and comfort. The purpose of this study was to build a nonlinear finite element model to investigate the interface pressure between the above-knee residual limb and its prosthetic socket. The model was three-dimensional (3D) with consideration of nonlinear boundary conditions. Contact analysis was used to simulate the friction conditions between skin and the socket. The normal stresses up to 80.57 kPa at the distal end of the soft tissue. The longitudinal and circumferential shear stress distributions at the limb-socket interface were also simulated. This study explores the influences of load transfer between trans-femoral residual limb and its prosthetic socket.

Experimental measurement of flexion-extension movement in normal and corpse prosthetic elbow joint.

Science.gov (United States)

TarniŢă, Daniela; TarniŢă, DănuŢ Nicolae

2016-01-01

This paper presents a comparative experimental study of flexion-extension movement in healthy elbow and in the prosthetic elbow joint fixed on an original experimental bench. Measurements were carried out in order to validate the functional morphology and a new elbow prosthesis type ball head. The three-dimensional (3D) model and the physical prototype of our experimental bench used to test elbow endoprosthesis at flexion-extension and pronation-supination movements is presented. The measurements were carried out on a group of nine healthy subjects and on the prosthetic corpse elbow, the experimental data being obtained for flexion-extension movement cycles. Experimental data for the two different flexion-extension tests for the nine subjects and for the corpse prosthetic elbow were acquired using SimiMotion video system. Experimental data were processed statistically. The corresponding graphs were obtained for all subjects in the experimental group, and for corpse prosthetic elbow for both flexion-extension tests. The statistical analysis has proved that the flexion angles of healthy elbows were significantly close to the values measured at the prosthetic elbow fixed on the experimental bench. The studied elbow prosthesis manages to re-establish the mobility for the elbow joint as close to the normal one.

The effect of prosthetic foot push-off on mechanical loading associated with knee osteoarthritis in lower extremity amputees.

Science.gov (United States)

Morgenroth, David C; Segal, Ava D; Zelik, Karl E; Czerniecki, Joseph M; Klute, Glenn K; Adamczyk, Peter G; Orendurff, Michael S; Hahn, Michael E; Collins, Steven H; Kuo, Art D

2011-10-01

Lower extremity amputation not only limits mobility, but also increases the risk of knee osteoarthritis of the intact limb. Dynamic walking models of non-amputees suggest that pushing-off from the trailing limb can reduce collision forces on the leading limb. These collision forces may determine the peak knee external adduction moment (EAM), which has been linked to the development of knee OA in the general population. We therefore hypothesized that greater prosthetic push-off would lead to reduced loading and knee EAM of the intact limb in unilateral transtibial amputees. Seven unilateral transtibial amputees were studied during gait under three prosthetic foot conditions that were intended to vary push-off. Prosthetic foot-ankle push-off work, intact limb knee EAM and ground reaction impulses for both limbs during step-to-step transition were measured. Overall, trailing limb prosthetic push-off work was negatively correlated with leading intact limb 1st peak knee EAM (slope=-.72±.22; p=.011). Prosthetic push-off work and 1st peak intact knee EAM varied significantly with foot type. The prosthetic foot condition with the least push-off demonstrated the largest knee EAM, which was reduced by 26% with the prosthetic foot producing the most push-off. Trailing prosthetic limb push-off impulse was negatively correlated with leading intact limb loading impulse (slope=-.34±.14; p=.001), which may help explain how prosthetic limb push-off can affect intact limb loading. Prosthetic feet that perform more prosthetic push-off appear to be associated with a reduction in 1st peak intact knee EAM, and their use could potentially reduce the risk and burden of knee osteoarthritis in this population. Published by Elsevier B.V.

Patient-specific prosthetic fingers by remote collaboration--a case study.

Directory of Open Access Journals (Sweden)

John-John Cabibihan

Full Text Available The concealment of amputation through prosthesis usage can shield an amputee from social stigma and help improve the emotional healing process especially at the early stages of hand or finger loss. However, the traditional techniques in prosthesis fabrication defy this as the patients need numerous visits to the clinics for measurements, fitting and follow-ups. This paper presents a method for constructing a prosthetic finger through online collaboration with the designer. The main input from the amputee comes from the Computer Tomography (CT data in the region of the affected and the non-affected fingers. These data are sent over the internet and the prosthesis is constructed using visualization, computer-aided design and manufacturing tools. The finished product is then shipped to the patient. A case study with a single patient having an amputated ring finger at the proximal interphalangeal joint shows that the proposed method has a potential to address the patient's psychosocial concerns and minimize the exposure of the finger loss to the public.

Prosthetic valves in adult patients with congenital heart disease : Rationale and design of the Dutch PROSTAVA study

NARCIS (Netherlands)

Freling, H. G.; van Slooten, Y. J.; van Melle, J. P.; Mulder, B. J. M.; van Dijk, A. P. J.; Hillege, H. L.; Post, M. C.; Sieswerda, G. Tj; Jongbloed, M. R. M.; Willems, T. P.; Pieper, P. G.

2012-01-01

Data on long-term complications in adult patients with congenital heart disease (ACHD) and a prosthetic valve are scarce. Moreover, the influence of prosthetic valves on quality of life (QoL) and functional outcome in ACHD patients with prosthetic valves has not been studied. The primary objective

Advances for prosthetic technology from historical perspective to current status to future application

CERN Document Server

LeMoyne, Robert

2016-01-01

This book focuses on the advances in transtibial prosthetic technology and targets research in the evolution of the powered prosthesis such as the BiOM, which was derived from considerable research and development at the Massachusetts Institute of Technology. The concept of the book spans the historical evolution of prosthetic applications from passive to new and futuristic robotic prosthetic technologies.  The author describes the reasons for amputation, surgical procedures, and an historical perspective of the prosthesis for the lower limb. He also addresses the phases and sub-phases of gait and compensatory mechanisms arising for a transtibial prosthesis and links the compensatory mechanisms to long-term morbidities.  The general technologies for gait analysis central to prosthetic design and the inherent biomechanics foundations for analysis are also explored.  The book reports on recent-past to current-term applications with passive elastic prostheses.  The core of the book deals with futuristic robo...

Multimodality Imaging Assessment of Prosthetic Heart Valves

NARCIS (Netherlands)

Suchá, D.; Symersky, Petr; Tanis, W; Mali, Willem P Th M; Leiner, Tim; van Herwerden, LA; Budde, Ricardo P J

Echocardiography and fluoroscopy are the main techniques for prosthetic heart valve (PHV) evaluation, but because of specific limitations they may not identify the morphological substrate or the extent of PHV pathology. Cardiac computed tomography (CT) and magnetic resonance imaging (MRI) have

Hand Motion-Based Remote Control Interface with Vibrotactile Feedback for Home Robots

Directory of Open Access Journals (Sweden)

Juan Wu

2013-06-01

Full Text Available This paper presents the design and implementation of a hand-held interface system for the locomotion control of home robots. A handheld controller is proposed to implement hand motion recognition and hand motion-based robot control. The handheld controller can provide a ‘connect-and-play’ service for the users to control the home robot with visual and vibrotactile feedback. Six natural hand gestures are defined for navigating the home robots. A three-axis accelerometer is used to detect the hand motions of the user. The recorded acceleration data are analysed and classified to corresponding control commands according to their characteristic curves. A vibration motor is used to provide vibrotactile feedback to the user when an improper operation is performed. The performances of the proposed hand motion-based interface and the traditional keyboard and mouse interface have been compared in robot navigation experiments. The experimental results of home robot navigation show that the success rate of the handheld controller is 13.33% higher than the PC based controller. The precision of the handheld controller is 15.4% more than that of the PC and the execution time is 24.7% less than the PC based controller. This means that the proposed hand motion-based interface is more efficient and flexible.

Prosthetic Joint Infection

Science.gov (United States)

Tande, Aaron J.

2014-01-01

SUMMARY Prosthetic joint infection (PJI) is a tremendous burden for individual patients as well as the global health care industry. While a small minority of joint arthroplasties will become infected, appropriate recognition and management are critical to preserve or restore adequate function and prevent excess morbidity. In this review, we describe the reported risk factors for and clinical manifestations of PJI. We discuss the pathogenesis of PJI and the numerous microorganisms that can cause this devastating infection. The recently proposed consensus definitions of PJI and approaches to accurate diagnosis are reviewed in detail. An overview of the treatment and prevention of this challenging condition is provided. PMID:24696437

Radiological visualization of prosthetic heart valves in situ

International Nuclear Information System (INIS)

Hoffmeister, H.M.; Pirschel, J.

1986-01-01

To determine the radiographic appearance of prosthetic heart valves 15 different models were investigated in situ. Fluoroscopy with detail radiographs and standard chest-radiographs were used for identification of the specific type of the prosthesis, for determination of details of the valve apparatus and for evaluation of the motion of the valve disc/ball. - Fluoroscopy and routine radiographs provided sufficient information to identify all prosthetic heart valves with exception of the Xenomedica bioprosthesis. If radiopaque material was used for the valve disc/ball, fluoroscopic assessment of the function of the valve was possible. Thus, in most types of disc or ball valves the opening/closing of the valve can be visualized, whereas in bioprosthesis a radiological determination of the mechanical function is not possible. (orig.) [de

Factors influencing the cost of prosthetic joint infection treatment.

Science.gov (United States)

Peel, T N; Cheng, A C; Lorenzo, Y P; Kong, D C M; Buising, K L; Choong, P F M

2013-11-01

Prosthetic joint infection (PJI) is associated with significant costs to the healthcare system. Current literature examines the cost of specific treatment modalities without assessing other cost drivers for PJI. To examine the overall cost of the treatment of PJI and to identify factors associated with management costs. The costs of treatment of prosthetic joint infections were examined in 139 patients across 10 hospitals over a 3-year period (January 2006 to December 2008). Cost calculations included hospitalization costs, surgical costs, hospital-in-the-home costs and antibiotic therapy costs. Negative binomial regression analysis was performed to model factors associated with total cost. The median cost of treating prosthetic joint infection per patient was Australian $34,800 (interquartile range: 20,305, 56,929). The following factors were associated with increased treatment costs: septic revision arthroplasty (67% increase in treatment cost; P = 0.02), hypotension at presentation (70% increase; P = 0.03), polymicrobial infections (41% increase; P = 0.009), surgical treatment with one-stage exchange (100% increase; P = 0.002) or resection arthroplasty (48% increase; P = 0.001) were independently associated with increased treatment costs. Culture-negative prosthetic joint infections were associated with decreased costs (29% decrease in treatment cost; P = 0.047). Treatment failure was associated with 156% increase in treatment costs. This study identifies clinically important factors influencing treatment costs that may be of relevance to policy-makers, particularly in the setting of hospital reimbursement and guiding future research into cost-effective preventive strategies. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Increased risk of prosthetic joint infection associated with esophago-gastro-duodenoscopy with biopsy.

Science.gov (United States)

Coelho-Prabhu, Nayantara; Oxentenko, Amy S; Osmon, Douglas R; Baron, Todd H; Hanssen, Arlen D; Wilson, Walter R; Steckelberg, James M; Baddour, Larry M; Harmsen, William S; Mandrekar, Jay; Berbari, Elie F

2013-02-01

There are no prospective data regarding the risk of prosthetic joint infection following routine gastrointestinal endoscopic procedures. We wanted to determine the risk of prosthetic hip or knee infection following gastrointestinal endoscopic procedures in patients with joint arthroplasty. We conducted a prospective, single-center, case-control study at a single, tertiary-care referral center. Cases were defined as adult patients hospitalized for prosthetic joint infection of the hip or knee between December 1, 2001 and May 31, 2006. Controls were adult patients with hip or knee arthroplasties but without a diagnosis of joint infection, hospitalized during the same time period at the same orthopedic hospital. The main outcome measure was the odds ratio (OR) of prosthetic joint infection after gastrointestinal endoscopic procedures performed within 2 years before admission. 339 cases and 339 controls were included in the study. Of these, 70 cases (21%) cases and 82 controls (24%) had undergone a gastrointestinal endoscopic procedure in the preceding 2 years. Among gastrointestinal procedures that were assessed, esophago-gastro-duodenoscopy (EGD) with biopsy was associated with an increased risk of prosthetic joint infection (OR = 3, 95% CI: 1.1-7). In a multivariable analysis adjusting for sex, age, joint age, immunosuppression, BMI, presence of wound drain, prior arthroplasty, malignancy, ASA score, and prothrombin time, the OR for infection after EGD with biopsy was 4 (95% CI: 1.5-10). EGD with biopsy was associated with an increased risk of prosthetic joint infection in patients with hip or knee arthroplasties. This association will need to be confirmed in other epidemiological studies and adequately powered prospective clinical trials prior to recommending antibiotic prophylaxis in these patients.

A smartphone photogrammetry method for digitizing prosthetic socket interiors.

Science.gov (United States)

Hernandez, Amaia; Lemaire, Edward

2017-04-01

Prosthetic CAD/CAM systems require accurate 3D limb models; however, difficulties arise when working from the person's socket since current 3D scanners have difficulties scanning socket interiors. While dedicated scanners exist, they are expensive and the cost may be prohibitive for a limited number of scans per year. A low-cost and accessible photogrammetry method for socket interior digitization is proposed, using a smartphone camera and cloud-based photogrammetry services. 15 two-dimensional images of the socket's interior are captured using a smartphone camera. A 3D model is generated using cloud-based software. Linear measurements were comparing between sockets and the related 3D models. 3D reconstruction accuracy averaged 2.6 ± 2.0 mm and 0.086 ± 0.078 L, which was less accurate than models obtained by high quality 3D scanners. However, this method would provide a viable 3D digital socket reproduction that is accessible and low-cost, after processing in prosthetic CAD software. Clinical relevance The described method provides a low-cost and accessible means to digitize a socket interior for use in prosthetic CAD/CAM systems, employing a smartphone camera and cloud-based photogrammetry software.

Prosthetic Leg Control in the Nullspace of Human Interaction.

Science.gov (United States)

Gregg, Robert D; Martin, Anne E

2016-07-01

Recent work has extended the control method of virtual constraints, originally developed for autonomous walking robots, to powered prosthetic legs for lower-limb amputees. Virtual constraints define desired joint patterns as functions of a mechanical phasing variable, which are typically enforced by torque control laws that linearize the output dynamics associated with the virtual constraints. However, the output dynamics of a powered prosthetic leg generally depend on the human interaction forces, which must be measured and canceled by the feedback linearizing control law. This feedback requires expensive multi-axis load cells, and actively canceling the interaction forces may minimize the human's influence over the prosthesis. To address these limitations, this paper proposes a method for projecting virtual constraints into the nullspace of the human interaction terms in the output dynamics. The projected virtual constraints naturally render the output dynamics invariant with respect to the human interaction forces, which instead enter into the internal dynamics of the partially linearized prosthetic system. This method is illustrated with simulations of a transfemoral amputee model walking with a powered knee-ankle prosthesis that is controlled via virtual constraints with and without the proposed projection.

The relevance of aortic endograft prosthetic infection

NARCIS (Netherlands)

Cernohorsky, Paul; Reijnen, Michel M. P. J.; Tielliu, Ignace F. J.; van Sterkenburg, Steven M. M.; van den Dungen, Jan J. A. M.; Zeebregts, Clark J.

Background: Vascular prosthetic graft infection is a severe complication after open aortic aneurysm repair. Reports of infected endografts are scarce. General treatment consensus with infected graft material is that it should be removed completely. The objective of this study was to describe the

Good quality of life outcomes after treatment of prosthetic joint infection with debridement and prosthesis retention.

Science.gov (United States)

Aboltins, Craig; Dowsey, Michelle; Peel, Trish; Lim, Wen K; Choong, Peter

2016-05-01

Patients treated for early prosthetic joint infection (PJI) with surgical debridement and prosthesis retention have a rate of successful infection eradication that is similar to patients treated with the traditional approach of prosthesis exchange. It is therefore important to consider other outcomes after prosthetic joint infection treatment that may influence management decisions, such as quality of life (QOL). Our aim was to describe infection cure rates and quality of life for patients with prosthetic joint infection treated with debridement and prosthesis retention and to determine if treatment with this approach was a risk factor for poor quality of life outcomes. Prospectively collected pre and post-arthroplasty data were available for 2,134 patients, of which PJI occurred in 41. For patients treated for prosthetic joint infection, the 2-year survival free of treatment failure was 87% (95%CI 84-89). Prosthetic joint infection cases treated with debridement and retention had a similar improvement from pre-arthroplasty to 12-months post-arthroplasty as patients without PJI in QOL according to the SF-12 survey. Prosthetic joint infection treated with debridement and retention was not a risk factor for poor quality of life on univariate or multivariate analysis. Prosthetic joint infection treated with debridement and prosthesis retention results in good cure rates and quality of life. Further studies are required that directly compare quality of life for different surgical approaches for prosthetic joint infection to better inform management decisions. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:898-902, 2016. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Measuring the Impact of Cognitive Prosthetics on the Daily Life of People with Dementia and Their Carers

Science.gov (United States)

Meiland, Franka; Dröes, Rose-Marie; Sävenstedt, Stefan

Assistive technologies to support persons with dementia and their carers are used increasingly often. However, little is known about the effectiveness of most assistive devices. Much technology is put on the market without having been properly tested with potential end-users. To increase the chance that an assistive device is well accepted and useful for the target group, it is important, especially in the case of disabled persons, to involve potential users in the development process and to evaluate the impact of using the device on them before implementing it in the daily care and support. When evaluating the impact, decisions have to be made regarding the selection of measuring instruments. Important considerations in the selection process are the underlying domains to be addressed by the assistive technology, the target group and the availability of standardized instruments with good psychometric properties. In this chapter the COGKNOW project is used as a case example to explain how the impact of cognitive prosthetics on the daily lives of people with dementia and their carers can be measured. In COGKNOW a cognitive prosthetic device is being developed to improve the quality of life and autonomy of persons with dementia and to help them to remember and remind, to have social contact, to perform daily activities and to enhance feelings of safety. For all these areas, potential measuring instruments are described. Besides (standardized) measuring instruments, other data collection methods are used as well, such as semi-structured interviews and observations, diaries and in situ measurement. Within the COGKNOW project a first uncontrolled small-scale impact measurement takes place during the development process of the assistive device. However, it is recommended to perform a larger randomized controlled study as soon as the final product is ready to evaluate the impact of the device on persons with dementia and carers before it is released on the market.

Smartphones as image processing systems for prosthetic vision.

Science.gov (United States)

Zapf, Marc P; Matteucci, Paul B; Lovell, Nigel H; Suaning, Gregg J

2013-01-01

The feasibility of implants for prosthetic vision has been demonstrated by research and commercial organizations. In most devices, an essential forerunner to the internal stimulation circuit is an external electronics solution for capturing, processing and relaying image information as well as extracting useful features from the scene surrounding the patient. The capabilities and multitude of image processing algorithms that can be performed by the device in real-time plays a major part in the final quality of the prosthetic vision. It is therefore optimal to use powerful hardware yet to avoid bulky, straining solutions. Recent publications have reported of portable single-board computers fast enough for computationally intensive image processing. Following the rapid evolution of commercial, ultra-portable ARM (Advanced RISC machine) mobile devices, the authors investigated the feasibility of modern smartphones running complex face detection as external processing devices for vision implants. The role of dedicated graphics processors in speeding up computation was evaluated while performing a demanding noise reduction algorithm (image denoising). The time required for face detection was found to decrease by 95% from 2.5 year old to recent devices. In denoising, graphics acceleration played a major role, speeding up denoising by a factor of 18. These results demonstrate that the technology has matured sufficiently to be considered as a valid external electronics platform for visual prosthetic research.

ARM-based visual processing system for prosthetic vision.

Science.gov (United States)

Matteucci, Paul B; Byrnes-Preston, Philip; Chen, Spencer C; Lovell, Nigel H; Suaning, Gregg J

2011-01-01

A growing number of prosthetic devices have been shown to provide visual perception to the profoundly blind through electrical neural stimulation. These first-generation devices offer promising outcomes to those affected by degenerative disorders such as retinitis pigmentosa. Although prosthetic approaches vary in their placement of the stimulating array (visual cortex, optic-nerve, epi-retinal surface, sub-retinal surface, supra-choroidal space, etc.), most of the solutions incorporate an externally-worn device to acquire and process video to provide the implant with instructions on how to deliver electrical stimulation to the patient, in order to elicit phosphenized vision. With the significant increase in availability and performance of low power-consumption smart phone and personal device processors, the authors investigated the use of a commercially available ARM (Advanced RISC Machine) device as an externally-worn processing unit for a prosthetic neural stimulator for the retina. A 400 MHz Samsung S3C2440A ARM920T single-board computer was programmed to extract 98 values from a 1.3 Megapixel OV9650 CMOS camera using impulse, regional averaging and Gaussian sampling algorithms. Power consumption and speed of video processing were compared to results obtained to similar reported devices. The results show that by using code optimization, the system is capable of driving a 98 channel implantable device for the restoration of visual percepts to the blind.

Effects of sterilization and storage on the properties of ALP-grafted biomaterials for prosthetic and bone tissue engineering applications

International Nuclear Information System (INIS)

Ferraris, S; Pan, G; Vernè, E; Spriano, S; Cassinelli, C; Mazzucco, L

2012-01-01

Grafting of the biomaterial surfaces with biomolecules is nowadays a challenging research field for prosthetic and bone tissue engineering applications. On the other hand, very few research works investigate the effect of the sterilization processes on the properties of functionalized biomaterials. In this study, the effects of different sterilization techniques (e.g. gamma and electron beam irradiation, ethylene oxide) on the enzymatic activity of bioactive glasses and Ti6Al4V grafted with alkaline phosphatase (ALP) have been analyzed. Sterility maintenance and in vitro bioactivity of the sterilized surfaces have also been investigated. Finally the effect of packaging and storage conditions has been considered. (paper)

Sensor fusion and computer vision for context-aware control of a multi degree-of-freedom prosthesis

Science.gov (United States)

Markovic, Marko; Dosen, Strahinja; Popovic, Dejan; Graimann, Bernhard; Farina, Dario

2015-12-01

Objective. Myoelectric activity volitionally generated by the user is often used for controlling hand prostheses in order to replicate the synergistic actions of muscles in healthy humans during grasping. Muscle synergies in healthy humans are based on the integration of visual perception, heuristics and proprioception. Here, we demonstrate how sensor fusion that combines artificial vision and proprioceptive information with the high-level processing characteristics of biological systems can be effectively used in transradial prosthesis control. Approach. We developed a novel context- and user-aware prosthesis (CASP) controller integrating computer vision and inertial sensing with myoelectric activity in order to achieve semi-autonomous and reactive control of a prosthetic hand. The presented method semi-automatically provides simultaneous and proportional control of multiple degrees-of-freedom (DOFs), thus decreasing overall physical effort while retaining full user control. The system was compared against the major commercial state-of-the art myoelectric control system in ten able-bodied and one amputee subject. All subjects used transradial prosthesis with an active wrist to grasp objects typically associated with activities of daily living. Main results. The CASP significantly outperformed the myoelectric interface when controlling all of the prosthesis DOF. However, when tested with less complex prosthetic system (smaller number of DOF), the CASP was slower but resulted with reaching motions that contained less compensatory movements. Another important finding is that the CASP system required minimal user adaptation and training. Significance. The CASP constitutes a substantial improvement for the control of multi-DOF prostheses. The application of the CASP will have a significant impact when translated to real-life scenarious, particularly with respect to improving the usability and acceptance of highly complex systems (e.g., full prosthetic arms) by amputees.

Dynamic elasticity measurement for prosthetic socket design.

Science.gov (United States)

Kim, Yujin; Kim, Junghoon; Son, Hyeryon; Choi, Youngjin

2017-07-01

The paper proposes a novel apparatus to measure the dynamic elasticity of human limb in order to help the design and fabrication of the personalized prosthetic socket. To take measurements of the dynamic elasticity, the desired force generated as an exponential chirp signal in which the frequency increases and amplitude is maintained according to time progress is applied to human limb and then the skin deformation is recorded, ultimately, to obtain the frequency response of its elasticity. It is referred to as a Dynamic Elasticity Measurement Apparatus (DEMA) in the paper. It has three core components such as linear motor to provide the desired force, loadcell to implement the force feedback control, and potentiometer to record the skin deformation. After measuring the force/deformation and calculating the dynamic elasticity of the limb, it is visualized as 3D color map model of the limb so that the entire dynamic elasticity can be shown at a glance according to the locations and frequencies. For the visualization, the dynamic elasticities measured at specific locations and frequencies are embodied using the color map into 3D limb model acquired by using 3D scanner. To demonstrate the effectiveness, the visualized dynamic elasticities are suggested as outcome of the proposed system, although we do not have any opportunity to apply the proposed system to the amputees. Ultimately, it is expected that the proposed system can be utilized to design and fabricate the personalized prosthetic socket in order for releasing the wearing pain caused by the conventional prosthetic socket.

38 CFR 17.122 - Payment or reimbursement of the expenses of repairs to prosthetic appliances and similar devices...

Science.gov (United States)

2010-07-01

... of the expenses of repairs to prosthetic appliances and similar devices furnished without prior... Payment or reimbursement of the expenses of repairs to prosthetic appliances and similar devices furnished without prior authorization. The expenses of repairs to prosthetic appliances, or similar appliances...

Using Arrays of Microelectrodes Implanted in Residual Peripheral Nerves to Provide Dextrous Control of, and Modulated Sensory Feedback from, a Hand Prosthesis

Science.gov (United States)

2015-10-01

extended that work by investigating multiple aspects important for developing future bidirectional neural prostheses based on high-count microelectrode...Fan J M, Kao J C, Stavisky S D, Ryu S and Shenoy K 2012 A recurrent neural network for closed-loop intracortical brain-machine interface decoders J...Peripheral Nerve Interface, Prosthetic Hand, Neural Prosthesis, Sensory Feedback, Micro-stimulation, Electrophysiology, Action Potentials, Micro

Utilization of penile prosthesis and male incontinence prosthetics in Saudi Arabia.

Science.gov (United States)

Alwaal, Amjad; Al-Sayyad, Ahmad J

2017-01-01

Erectile dysfunction is a prevalent disease affecting over 50% of men between the ages of 40 and 70 years. Penile prosthesis represents the end of the line treatment when other less invasive therapies fail or are contraindicated. Male stress urinary incontinence can significantly diminish quality of life and lead to embarrassment and social withdrawal. Surgical therapies, such as male urethral slings and artificial urinary sphincters (AUS), are considered effective and safe treatments for male stress incontinence. No data exist on the utilization of penile prosthesis or male incontinence surgical treatment in Saudi Arabia. Generally, urological prosthetic surgery is performed either in private hospitals or in government hospitals. Our aim was to assess the trend of penile prosthesis and male incontinence device utilization in Saudi Arabia. We utilized sales' data of penile prosthetics, male slings, and AUS from the only two companies selling these devices in Saudi Arabia (AMS ® and Coloplast ® ), from January 2013 to December 2016. There were 2599 penile prosthesis implantation procedures done in the study period, with 67% of them performed in private institutions. There was a progressively increased use of penile prosthetics which nearly doubled from 2013 to 2016. The main type of prosthesis utilized was the semirigid type 70% versus 11% of the 2-piece inflatable and 17% of the 3-piece inflatable device. Only 10 slings and 31 AUS were inserted during the same study period. There is an increased utilization of penile prosthetics in Saudi Arabia. The private sector performs the majority of penile prosthesis procedures, and most of them are of the semirigid type. The governmental sector is more likely to perform inflatable penile prosthesis and male incontinence device procedures. Male incontinence prosthetics' use is very limited in Saudi Arabia.

Acinetobacter Prosthetic Joint Infection Treated with Debridement and High-Dose Tigecycline.

Science.gov (United States)

Vila, Andrea; Pagella, Hugo; Amadio, Claudio; Leiva, Alejandro

2016-12-01

Prosthesis retention is not recommended for multidrug-resistant Acinetobacter prosthetic joint infection due to its high failure rate. Nevertheless, replacing the prosthesis implies high morbidity and prolonged hospitalization. Although tigecycline is not approved for the treatment of prosthetic joint infection due to multidrug resistant Acinetobacter baumannii, its appropriate use may preclude prosthesis exchange. Since the area under the curve divided by the minimum inhibitory concentration is the best pharmacodynamic predictor of its efficacy, we used tigecycline at high dose, in order to optimize its efficacy and achieve implant retention in 3 patients who refused prosthesis exchange. All patients with prosthetic joint infections treated at our Institution are prospectively registered in a database. Three patients with early prosthetic joint infection of total hip arthroplasty due to multidrug resistant A. baumannii were treated with debridement, antibiotics and implant retention, using a high maintenance dose of tigecycline (100 mg every 12 hours). The cases were retrospectively reviewed. All patients signed informed consent for receiving off-label use of tigecycline. Tigecycline was well tolerated, allowing its administration at high maintenance dose for a median of 40 days (range 30-60). Two patients were then switched to minocycline at standard doses for a median of 3.3 months in order to complete treatment. Currently, none of the patients showed relapse. Increasing the dose of tigecycline could be considered as a means to better attain pharmacodynamic targets in patients with severe or difficult-to-treat infections. Tigecycline at high maintenance dose might be useful when retention of the implant is attempted for treatment for prosthetic joint infections due to multidrug resistant Acinetobacter. Although this approach might be promising, off-label use of tigecycline should be interpreted cautiously until prospective data are available. Tigecycline is

Evaluation of prosthetic heart valves by transesophageal echocardiography: problems, pitfalls, and timing of echocardiography

NARCIS (Netherlands)

van den Brink, Renee B. A.

2006-01-01

Transesophageal echocardiography (TEE) is especially suitable for examination of prosthetic valves because of the proximity of the esophagus to the heart and absence of interference with lungs and ribs. This article reviews normal and abnormal morphologic characteristics of prosthetic valves such as

Assessment of the bacterial contamination of hand air dryer in washrooms.

Science.gov (United States)

Alharbi, Sulaiman Ali; Salmen, Saleh Hussein; Chinnathambi, Arunachalam; Alharbi, Naiyf S; Zayed, M E; Al-Johny, Bassam O; Wainwright, Milton

2016-03-01

The present study was carried out, using standard techniques, to identify and count the bacterial contamination of hand air dryers, used in washrooms. Bacteria were isolated from the air flow, outlet nozzle of warm air dryers in fifteen air dryers used in these washrooms. Bacteria were found to be relatively numerous in the air flows. Bacterially contaminated air was found to be emitted whenever a warm air dryer was running, even when not being used for hand drying. Our investigation shows that Staphylococcus haemolyticus, Micrococcus luteus, Pseudomonas alcaligenes, Bacillus cereus and Brevundimonad diminuta/vesicularis were emitted from all of the dryers sampled, with 95% showing evidence of the presence of the potential pathogen S. haemolyticus. It is concluded that hot air dryers can deposit pathogenic bacteria onto the hands and body of users. Bacteria are distributed into the general environment whenever dryers are running and could be inhaled by users and none-users alike. The results provide an evidence base for the development and enhancement of hygienic hand drying practices.

CRITERIA FOR THE EVALUATION AND ESTIMATION OF IATROGENIC PROSTHETIC FACTORS – SEMIOLOGY AND SYMPTOMATOLOGY

Directory of Open Access Journals (Sweden)

G. LUCA

2013-12-01

Full Text Available Introduction: The principles lying at the basis of a balanced dental occlusion cannot be analyzed separately, but only if considering the teeth (and, implicitly, dental occlusion as integrated into the masticatory system, which includes the masticatory muscles, the temporo-mandibu‑ lary joint and the maxillary bones. Scope: The scope of the present study was to correlate and establish the interde‑ pendence between the morpholgically-incorrect prosthetic works and the tissular and functional damages suffered by the neighbouring structures, as a result of some incor‑ rectly-made prosthetic works. Also, the study aims at iden‑ tifying the factors and limits responsible for a prolongued maintenance of such irreversible pathological modificati‑ ons within an asymptomatic zone for the patient. Materials and method: The working hypothesis of the present inves‑ tigation started from the analysis of the various objective signs, versus the morphology of the incorrectly performed prosthetic works. The study, initiated as early as 2009, in a private stomatological clinics (DentEstet, Bucuresti, includes a number of 500 patients (250 women and 250 men, selected among the patients having addressed the stomatological office from various reasons (not always related to the prosthetic pathology of the cases here under investigation. Included in the study have been only the patients with fixed prosthetic works associated with one or several of the previously described objective signs, potentially induced by the iatrogeneicity of the prosthetic works. Results: The pathological effects of the iatrogenic works here under analysis, upon both the antagonistic and prosthetic support teeth, may be clinically identified during a minute examination performed prior to produ‑ cing irreversible final effects (abrasions, fractures, dental mobility, etc.. Such noxious effects of the iatrogenic pros‑ thetic works appear as a false masticatory comfort and as a

Pre-operative Asymptomatic Bacteriuria: A Risk Factor For Prosthetic Joint Infection?

Science.gov (United States)

Weale, R; El-Bakri, F; Saeed, Kordo

2018-04-13

Infection is a rare complication following implantation of prosthetic material into a joint. The impact of asymptomatic bacteriuria (ASB) before elective operations and the subsequent risk of prosthetic joint infection (PJI) are not well understood. • Assess the prevalence of ASB amongst patients undergoing total arthroplasty of the hip and knee. • Determine the rates of PJI diagnosed within two years of the arthroplasty and if ASB is an independent risk factor for developing PJI. Patients who had total/unicondylar knee or total hip arthroplasty were retrospectively reviewed over a five-year period. Pre-operative urine samples within one year of surgery were analysed and those with ASB identified. Primary outcome was prosthetic joint infection (PJI) within the first postoperative year. 5542 patients were included. 4368 had a pre-operative urine culture recorded. The prevalence of ASB was 140 of 4368 (3.2%). The overall PJI rate was 56 of 5542 (1.01%). Of those with a PJI, 33 had a pre-operative urine sample recorded. The infection rate in the ASB group was 5% (7 of 140), in the no-ASB group it was 0.61% (26 of 4228) and in the group without a urine sample it was 1.96% (23 of 1174) (p value prosthetic joint, suggestive the relationship is unlikely causal. Copyright © 2018. Published by Elsevier Ltd.

Prosthetics & Orthotics Manufacturing Initiative (POMI)

Science.gov (United States)

2012-12-21

suspension system, socket- ankle /knee interface, etc.) associated with a complete prosthetic system. More specific, the purpose of these deliverables was...strap. The waist belt consists of an adjustable belt utilizing polypropylene buckles and a 2‖ elastic suspension strap which descends to the anchor ...Superior View. Step 8: The suspension component consists of a 1’ anchor strap with a buckle and a 5’ – 6’ long shoulder strap with hook and

Single-stage revision for fungal peri-prosthetic joint infection: a single-centre experience.

Science.gov (United States)

Klatte, T O; Kendoff, D; Kamath, A F; Jonen, V; Rueger, J M; Frommelt, L; Gebauer, M; Gehrke, T

2014-04-01

Fungal peri-prosthetic infections of the knee and hip are rare but likely to result in devastating complications. In this study we evaluated the results of their management using a single-stage exchange technique. Between 2001 and 2011, 14 patients (ten hips, four knees) were treated for a peri-prosthetic fungal infection. One patient was excluded because revision surgery was not possible owing to a large acetabular defect. One patient developed a further infection two months post-operatively and was excluded from the analysis. Two patients died of unrelated causes. After a mean of seven years (3 to 11) a total of ten patients were available for follow-up. One patient, undergoing revision replacement of the hip, had a post-operative dislocation. Another patient, undergoing revision replacement of the knee, developed a wound infection and required revision 29 months post-operatively following a peri-prosthetic femoral fracture. The mean Harris hip score increased to 74 points (63 to 84; p prosthetic infection is feasible, with an acceptable rate of a satisfactory outcome.

Aerogel Use as a Skin Protective Liner In Space Suits and Prosthetic Limbs Project

Science.gov (United States)

Roberson, Luke Bennett

2014-01-01

Existing materials for prosthetic liners tend to be thick and airtight, causing perspiration to accumulate inside the liner and potentially causing infection and injury. The purpose of this project was to examine the suitability of aerogel for prosthetic liner applications for use in space suits and orthopedics. Three tests were performed on several types of aerogel to assess the properties of each material, and our initial findings demonstrated that these materrials would be excellent candidates for liner applications for prosthetics and space suits. The project is currently on hold until additional funding is obtained for application testing at the VH Hospitals in Tampa

Development and acceptability testing of decision trees for self-management of prosthetic socket fit in adults with lower limb amputation.

Science.gov (United States)

Lee, Daniel Joseph; Veneri, Diana A

2018-05-01

The most common complaint lower limb prosthesis users report is inadequacy of a proper socket fit. Adjustments to the residual limb-socket interface can be made by the prosthesis user without consultation of a clinician in many scenarios through skilled self-management. Decision trees guide prosthesis wearers through the self-management process, empowering them to rectify fit issues, or referring them to a clinician when necessary. This study examines the development and acceptability testing of patient-centered decision trees for lower limb prosthesis users. Decision trees underwent a four-stage process: literature review and expert consultation, designing, two-rounds of expert panel review and revisions, and target audience testing. Fifteen lower limb prosthesis users (average age 61 years) reviewed the decision trees and completed an acceptability questionnaire. Participants reported agreement of 80% or above in five of the eight questions related to acceptability of the decision trees. Disagreement was related to the level of experience of the respondent. Decision trees were found to be easy to use, illustrate correct solutions to common issues, and have terminology consistent with that of a new prosthesis user. Some users with greater than 1.5 years of experience would not use the decision trees based on their own self-management skills. Implications for Rehabilitation Discomfort of the residual limb-prosthetic socket interface is the most common reason for clinician visits. Prosthesis users can use decision trees to guide them through the process of obtaining a proper socket fit independently. Newer users may benefit from using the decision trees more than experienced users.

Successful Thrombolysis of Aortic Prosthetic Valve Thrombosis ...

African Journals Online (AJOL)

Arun Kumar Agnihotri

patients with valvular heart disease). Endorsed by the Society of Cardiovascular. Anesthesiologists, Society for Cardiovascular. Angiography and Interventions, and Society of. Thoracic Surgeons. J Am Coll Cardiol. 2008;52(13):e1-142. 5. Elkayam U, Bitar F. Valvular heart disease and pregnancy. Part II: prosthetic valves.

Consumer satisfaction in prosthetics and orthotics facilities

NARCIS (Netherlands)

Geertzen, J.H.B.; Gankema, H.G.J.; Groothoff, J.W.; Dijkstra, P.U.

The aim of this study was to assess consumer/patient satisfaction with the services of the prosthetics and orthotics (P&O) facilities in the north of the Netherlands, using a modified SERVQUAL questionnaire. In this questionnaire, consumer interests and experiences are assessed on a 5-point Likert

Prosthetic valve obstruction: Redo surgery or fibrinolysis?

Directory of Open Access Journals (Sweden)

Avinash Inamdar

2017-01-01

Full Text Available Objective: The aim of this study was to compare the efficacy and safety of surgery versus fibrinolytic therapy in patients with prosthetic valve obstruction. Materials and Methods: We compared 15 patients of prosthetic valve thrombosis treated by surgical line of management and another 15 patients treated by thrombolysis. All patients were initially assessed by clinical evaluation and diagnosis confirmed by transthoracic and transesophageal two-dimensional echocardiography. Depending on hemodynamic stability, pannus, or thrombus on transesophageal echocardiography, the patients were assigned surgical or medical line of management. Results: Patients mortality rate was 40% in fibrinolytic group and 13.33% in surgical group. Recurrence was 40% in fibrinolytic group while there was no recurrence till date in surgery group. Complications were more in fibrinolytic group as opposed to surgery group patient. Conclusion: From our experience, we conclude that redo surgery is effective and definitive treatment, especially in patients with stable hemodynamic conditions.

Self-cleaning skin-like prosthetic polymer surfaces

Science.gov (United States)

Simpson, John T [Clinton, TN; Ivanov, Ilia N [Knoxville, TN; Shibata, Jason [Manhattan Beach, CA

2012-03-27

An external covering and method of making an external covering for hiding the internal endoskeleton of a mechanical (e.g., prosthetic) device that exhibits skin-like qualities is provided. The external covering generally comprises an internal bulk layer in contact with the endoskeleton of the prosthetic device and an external skin layer disposed about the internal bulk layer. The external skin layer is comprised of a polymer composite with carbon nanotubes embedded therein. The outer surface of the skin layer has multiple cone-shaped projections that provide the external skin layer with superhydrophobicity. The carbon nanotubes are preferably vertically aligned between the inner surface and outer surface of the external skin layer in order to provide the skin layer with the ability to transmit heat. Superhydrophobic powders may optionally be used as part of the polymer composite or applied as a coating to the surface of the skin layer to enhance superhydrophobicity.

An evaluation of prosthetic status and treatment needs among institutionalized elderly individuals of Delhi, India

OpenAIRE

Nisha Yadav; Roma Yadav; Meetika Pahuja; Sanchit Pardhan; Sahiba Miglani; Tamanna Malik

2017-01-01

Context: Oral health is essential for elderly person's general health and well-being. The most common oral problem in elderly is tooth loss which results due to periodontal diseases and caries. Prosthetic status is very important as it is related to dietary intake and maintaining nutritional status. Hence, to promote the oral health of the elderly, we need to know their prosthetic status and need. Aims: The aim of this study is to find the prosthetic status and need of 65–74 years old elderly...

Immediate effects of a new microprocessor-controlled prosthetic knee joint: a comparative biomechanical evaluation.

Science.gov (United States)

Bellmann, Malte; Schmalz, Thomas; Ludwigs, Eva; Blumentritt, Siegmar

2012-03-01

To investigate the immediate biomechanical effects after transition to a new microprocessor-controlled prosthetic knee joint. Intervention cross-over study with repeated measures. Only prosthetic knee joints were changed. Motion analysis laboratory. Men (N=11; mean age ± SD, 36.7±10.2y; Medicare functional classification level, 3-4) with unilateral transfemoral amputation. Two microprocessor-controlled prosthetic knee joints: C-Leg and a new prosthetic knee joint, Genium. Static prosthetic alignment, time-distance parameters, kinematic and kinetic parameters, and center of pressure. After a half-day training and an additional half-day accommodation, improved biomechanical outcomes were demonstrated by the Genium: lower ground reaction forces at weight acceptance during level walking at various velocities, increased swing phase flexion angles during walking on a ramp, and level walking with small steps. Maximum knee flexion angle during swing phase at various velocities was nearly equal for Genium. Step-over-step stair ascent with the Genium knee was more physiologic as demonstrated by a more equal load distribution between the prosthetic and contralateral sides and a more natural gait pattern. When descending stairs and ramps, knee flexion moments with the Genium tended to increase. During quiet stance on a decline, subjects using Genium accepted higher loading of the prosthetic side knee joint, thus reducing same side hip joint loading as well as postural sway. In comparision to the C-Leg, the Genium demonstrated immediate biomechanical advantages during various daily ambulatory activities, which may lead to an increase in range and diversity of activity of people with above-knee amputations. Results showed that use of the Genium facilitated more natural gait biomechanics and load distribution throughout the affected and sound musculoskeletal structure. This was observed during quiet stance on a decline, walking on level ground, and walking up and down ramps and

Prosthetic joint infection caused by Pasteurella multocida: a case series and review of literature.

Science.gov (United States)

Honnorat, Estelle; Seng, Piseth; Savini, Hélène; Pinelli, Pierre-Olivier; Simon, Fabrice; Stein, Andreas

2016-08-20

Pasteurella multocida is a well-recognized zoonotic agent following dog or cat bites or scratches. Nevertheless, prosthetic joint infection caused by P. multocida are rarely reported. We report here a series of six cases of prosthetic joint infection caused by P. multocida managed at a referral centre for the treatment of bone and joint infection in southern France. We also reviewed the 26 cases reported in literature. The mean age of our cases was 74 years [±8.2, range 63-85]. In majority of our cases (5 cases) were associated with knee prostheses and one case with a hip prosthesis. Most of cases occurred after cat or dog scratches or licks or contact. Diagnoses of prosthetic joint infection caused by P. multocida were made by positive cultures of surgical biopsies or needle aspiration. Mean time delay between prosthetic joint implantation and infection onset was 7.6 years (±5.12 years, range 2-17). Local inflammation, which occurred in all six cases, was the most frequent clinical symptom, followed by pain in five cases, fever and swollen joints in four cases, and a fistula with purulent discharge inside the wound in two cases. The mean time of antibiotic therapy was 8 months. Surgical treatment with prosthesis removal was performed in three cases. Six of our cases were in remission without apparent relapse at 3 years after end of treatment. Prosthetic joint infections caused by P. multocida usually occur after animal scratches or bites, but can occasionally occur after a short animal lick. These infections are usually resulting from a contiguous infection and localized in the knee. An early antibiotic therapy after surgical debridement could avoid prosthetic withdrawal, notably in elderly patients. Patients with prosthetic joints should be warned that animals are potential sources of serious infection and urgent medical advice should be sought if they are bitten or scratched.

Systematic variation of prosthetic foot spring affects center-of-mass mechanics and metabolic cost during walking.

Science.gov (United States)

Zelik, Karl E; Collins, Steven H; Adamczyk, Peter G; Segal, Ava D; Klute, Glenn K; Morgenroth, David C; Hahn, Michael E; Orendurff, Michael S; Czerniecki, Joseph M; Kuo, Arthur D

2011-08-01

Lower-limb amputees expend more energy to walk than non-amputees and have an elevated risk of secondary disabilities. Insufficient push-off by the prosthetic foot may be a contributing factor. We aimed to systematically study the effect of prosthetic foot mechanics on gait, to gain insight into fundamental prosthetic design principles. We varied a single parameter in isolation, the energy-storing spring in a prototype prosthetic foot, the controlled energy storage and return (CESR) foot, and observed the effect on gait. Subjects walked on the CESR foot with three different springs. We performed parallel studies on amputees and on non-amputees wearing prosthetic simulators. In both groups, spring characteristics similarly affected ankle and body center-of-mass (COM) mechanics and metabolic cost. Softer springs led to greater energy storage, energy return, and prosthetic limb COM push-off work. But metabolic energy expenditure was lowest with a spring of intermediate stiffness, suggesting biomechanical disadvantages to the softest spring despite its greater push-off. Disadvantages of the softest spring may include excessive heel displacements and COM collision losses. We also observed some differences in joint kinetics between amputees and non-amputees walking on the prototype foot. During prosthetic push-off, amputees exhibited reduced energy transfer from the prosthesis to the COM along with increased hip work, perhaps due to greater energy dissipation at the knee. Nevertheless, the results indicate that spring compliance can contribute to push-off, but with biomechanical trade-offs that limit the degree to which greater push-off might improve walking economy. © 2011 IEEE

Spatial limits on the nonvisual self-touch illusion and the visual rubber hand illusion: subjective experience of the illusion and proprioceptive drift.

Science.gov (United States)

Aimola Davies, Anne M; White, Rebekah C; Davies, Martin

2013-06-01

The nonvisual self-touch rubber hand paradigm elicits the compelling illusion that one is touching one's own hand even though the two hands are not in contact. In four experiments, we investigated spatial limits of distance (15 cm, 30 cm, 45 cm, 60 cm) and alignment (0°, 90° anti-clockwise) on the nonvisual self-touch illusion and the well-known visual rubber hand illusion. Common procedures (synchronous and asynchronous stimulation administered for 60s with the prosthetic hand at body midline) and common assessment methods were used. Subjective experience of the illusion was assessed by agreement ratings for statements on a questionnaire and time of illusion onset. The nonvisual self-touch illusion was diminished though never abolished by distance and alignment manipulations, whereas the visual rubber hand illusion was more robust against these manipulations. We assessed proprioceptive drift, and implications of a double dissociation between subjective experience of the illusion and proprioceptive drift are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

The Prosthetic Experience Between Body and Technology

DEFF Research Database (Denmark)

Søndergaard, Morten

2018-01-01

In this paper, I argue that a prosthetic aesthetic instigated by experimental art practices operate with and within a ‘second nature’ – in-between science and art. Drawing on theories from Dewey and Edelman and examples from Da Vinci, Brancusi, Man Ray, Dali and Stelarc, I am calling...

Aortic allografts in treatment of aortic valve and ascending aorta prosthetic endocarditis

Directory of Open Access Journals (Sweden)

S.V. Spiridonov

2017-03-01

Full Text Available The aim – to assess short- and long-term results of aortic root replacement using aortic allografts in patients with prosthetic endocarditis. Materials and methods. Since February 2009 until June 2016 aortic valve and ascending aorta replacement using aortic allografts was performed in 26 patients with prosthetic endocarditis. In 50 % of cases at initial operation aortic valve replacement was performed, in another 50 % of cases – aortic valve and ascending aorta replacement. Echocardiography was performed 10 days, 3, 6 and 12 months, 2, 3 and 5 years after surgery. Analysis of long-term results included all cases of deaths, prosthesis-related complications and recurrence of endocarditis. Results. 30-day mortality was 23.1 %. Extracorporeal membranous oxygenation (ECMO was used only in 5 patients (19.2 %. Four patients were weaned from ECMO. We did not observe any allograft-related complications. During follow-up period there were no cases of reoperation due to structural allograft failure. Relapse of infection occurred in 1 patient (3.8 % four years after the operation and led to lethal outcome. Conclusion. Reoperations using allografts are an effective surgical treatment of prosthetic endocarditis. In majority of cases prosthetic endocarditis was caused by gram-positive cocci (Staphylococcus. In 84.6 % of cases it was associated with destruction of paravalvular structures and abscesses formation. Heart failure was a causative factor of different complications in these patients, which required ECMO in 19.2 % of patients. In 80 % of cases patients were weaned from ECMO. Allografts using for the treatment of prosthetic endocarditis is associated with high resistance to infection and with a significant rate of freedom from recurrence of endocarditis within 3 years after surgery.

Prosthetic Hand Technology-Phase II

Science.gov (United States)

2013-02-01

Science and Technology 54: 327-334. 6. Lewinski, N., Colvin, V., and Drezek, R. (2008). Cytotoxicity of nanoparticles. small 4(1):26-49. 7. Barik , T.K...Drezek, R. (2008). Cytotoxicity of nanoparticles. small 4(1):26-49. 7. Barik , T.K., Sahu, B., and Swain, V. (2008). Nanosilica — from medicine to pest

Selected applications for current polymers in prosthetic dentistry - state of the art.

Science.gov (United States)

Kawala, Maciej; Smardz, Joanna; Adamczyk, Lukasz; Grychowska, Natalia; Wieckiewicz, Mieszko

2018-05-10

Polymers are widely applied in medicine, including dentistry, i.e. in prosthodontics. The following paper is aimed at demonstrating the applications of selected modern polymers in prosthetic dentistry based on the reported literature. The study was conducted using the PubMed, SCOPUS and CINAHL databases in relation to documents published during 1999-2017. The following keywords were used: polymers with: prosthetic dentistry, impression materials, denture base materials, bite registration materials, denture soft liners, occlusal splint materials and 3D printing. Original papers and reviews which were significant from the modern clinical viewpoint and practical validity in relation to the possibility of using polymeric materials in prosthetic dentistry, were presented. Denture base materials were most commonly modified polymers. Modifications mainly concerned antimicrobial properties and reinforcement of the material structure by introducing additional fibers. Antimicrobial modifications were also common in case of relining materials. Polymeric materials have widely been used in prosthetic dentistry. Modifications of their composition allow achieving new, beneficial properties that affect quality of patients' life. Progress in science allows for a more methodologically-advanced research on the synthesis of new polymeric materials and incorporation of new substances into already known polymeric materials, that will require systematization and appropriate classification. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

More with less: A comparative kinematical analysis of Django Reinhardt's adaptations to hand injury.

Science.gov (United States)

Wininger, Michael; Williams, David J

2015-06-01

At the age of 18 years, jazz guitarist Django Reinhardt (1910-1953) sustained significant burns to his left-hand ring and little fingers; yet, subsequently, he relearned to play and achieved international fame, despite his injuries. Archive film footage and novel motion analysis software were used to compare movements of Django's fretting hand with that of six other guitarists of the same genre. Django employed greater abduction of index and middle fingers (-9.11 ± 6.52° vs -5.78 ± 2.41°; p < 0.001) and more parallel alignment of fingers to the guitar neck (157.7 ± 3.37° vs 150.59 ± 2.67°; p < 0.001) compared to controls. In response to debilitating hand injury, Django developed quantifiable compensatory adaptation of function of his remaining functional fingers by developing an original playing technique. Hand function following injury may be optimized by maximizing latent degrees of freedom in remaining digits, rather than through extensive surgical reconstruction or complex prostheses. Further study of adaptation strategies may inform prosthesis design. © The International Society for Prosthetics and Orthotics 2014.

Characterization of microbes in prosthetic joint specimens by culture-independent molecular methods

DEFF Research Database (Denmark)

Xu, Yijuan; Rudkjøbing, Vibeke Børsholt; Simonsen, Ole

Prosthetic joint infection (PJI) is one of the most challenging complications of joint alloplasty. Formation of biofilm is a prominent feature of PJIs and constitutes a challenge to current sampling procedures and culture practices to obtain a reliable diagnosis. The aim of the study was to inves......Prosthetic joint infection (PJI) is one of the most challenging complications of joint alloplasty. Formation of biofilm is a prominent feature of PJIs and constitutes a challenge to current sampling procedures and culture practices to obtain a reliable diagnosis. The aim of the study...... was to investigate the microbial diversity in surgical samples (eg. synovial fluid, periprosthetic tissue, removed prosthesis) from 22 prosthetic patients using a range of culture-independent molecular methods including broad range 16S rRNA gene PCR, cloning, phylogeny, quantitative PCR (qPCR), and fluorescence...

Novel implant for peri-prosthetic proximal tibia fractures.

Science.gov (United States)

Tran, Ton; Chen, Bernard K; Wu, Xinhua; Pun, Chung Lun

2018-03-01

Repair of peri-prosthetic proximal tibia fractures is very challenging in patients with a total knee replacement or arthroplasty. The tibial component of the knee implant severely restricts the fixation points of the tibial implant to repair peri-prosthetic fractures. A novel implant has been designed with an extended flange over the anterior of tibial condyle to provide additional points of fixation, overcoming limitations of existing generic locking plates used for proximal tibia fractures. Furthermore, the screws fixed through the extended flange provide additional support to prevent the problem of subsidence of tibial component of knee implant. The design methodology involved extraction of bone data from CT scans into a flexible CAD format, implant design and structural evaluation and optimisation using FEM as well as prototype development and manufacture by selective laser melting 3D printing technology with Ti6Al4 V powder. A prototype tibia implant was developed based on a patient-specific bone structure, which was regenerated from the CT images of patient's tibia. The design is described in detail and being applied to fit up to 80% of patients, for both left and right sides based on the average dimensions and shape of the bone structure from a wide range of CT images. A novel tibial implant has been developed to repair peri-prosthetic proximal tibia fractures which overcomes significant constraints from the tibial component of existing knee implant. Copyright © 2018 Elsevier Ltd. All rights reserved.

Nitinol for Prosthetic and Orthotic Applications

Science.gov (United States)

Henderson, Emma; Buis, Arjan

2011-07-01

As global populations age, conditions such as stroke and diabetes require individuals to use rehabilitation technology for many years to come due to chronic musculoskeletal, sensory, and other physical impairments. One in four males currently aged 45 will experience a stroke within 40 years and will often require access to prolonged rehabilitation. In addition, worldwide, one individual loses a limb every 30 s due to the complications of diabetes. As a result, innovative ideas are required to devise more effective prosthetic and orthotic devices to enhance quality of life. While Nitinol has already found much favor within the biomedical industry, one area, which has not yet exploited its unique properties, is in the field of physical rehabilitation, ranging from prosthetic and orthotic devices to assistive technology such as wheelchairs. Improved intervention capabilities based on materials such as Nitinol have the potential to vastly improve patients' quality of life and in the case of orthoses, may even reduce the severity of the condition over time. It is hoped that this study will spark discussion and interest for the materials community in a field which has yet to be fully exploited.

Simplification of Visual Rendering in Simulated Prosthetic Vision Facilitates Navigation.

Science.gov (United States)

Vergnieux, Victor; Macé, Marc J-M; Jouffrais, Christophe

2017-09-01

Visual neuroprostheses are still limited and simulated prosthetic vision (SPV) is used to evaluate potential and forthcoming functionality of these implants. SPV has been used to evaluate the minimum requirement on visual neuroprosthetic characteristics to restore various functions such as reading, objects and face recognition, object grasping, etc. Some of these studies focused on obstacle avoidance but only a few investigated orientation or navigation abilities with prosthetic vision. The resolution of current arrays of electrodes is not sufficient to allow navigation tasks without additional processing of the visual input. In this study, we simulated a low resolution array (15 × 18 electrodes, similar to a forthcoming generation of arrays) and evaluated the navigation abilities restored when visual information was processed with various computer vision algorithms to enhance the visual rendering. Three main visual rendering strategies were compared to a control rendering in a wayfinding task within an unknown environment. The control rendering corresponded to a resizing of the original image onto the electrode array size, according to the average brightness of the pixels. In the first rendering strategy, vision distance was limited to 3, 6, or 9 m, respectively. In the second strategy, the rendering was not based on the brightness of the image pixels, but on the distance between the user and the elements in the field of view. In the last rendering strategy, only the edges of the environments were displayed, similar to a wireframe rendering. All the tested renderings, except the 3 m limitation of the viewing distance, improved navigation performance and decreased cognitive load. Interestingly, the distance-based and wireframe renderings also improved the cognitive mapping of the unknown environment. These results show that low resolution implants are usable for wayfinding if specific computer vision algorithms are used to select and display appropriate

Comparing Facebook Users and Facebook Non-Users: Relationship between Personality Traits and Mental Health Variables - An Exploratory Study.

Science.gov (United States)

Brailovskaia, Julia; Margraf, Jürgen

2016-01-01

Over one billion people use Facebook as a platform for social interaction and self-presentation making it one of the most popular online sites. The aim of the present study was to investigate differences in various personality traits and mental health variables between Facebook users and people who do not use this platform. The data of 945 participants (790 Facebook users, 155 Facebook non-users) were collected. Results indicate that Facebook users score significantly higher on narcissism, self-esteem and extraversion than Facebook non-users. Furthermore, they have significantly higher values of social support, life satisfaction and subjective happiness. Facebook non-users have (marginally) significantly higher values of depression symptoms than Facebook users. In both groups, extraversion, self-esteem, happiness, life satisfaction, resilience and social support, on the one hand, and depression, anxiety and stress symptoms, on the other hand, are negatively correlated. Neuroticism is positively associated with depression, anxiety and stress symptoms. However, significant differences exist between Facebook users and Facebook non-users regarding some associations of personality traits and mental health variables. Compared to Facebook non-users, the present results indicate that Facebook users have higher values of certain personality traits and positive variables protecting mental health. These findings are of particular interest considering the high importance of social online-platforms in the daily life of many people.

Comparing Facebook Users and Facebook Non-Users: Relationship between Personality Traits and Mental Health Variables - An Exploratory Study.

Directory of Open Access Journals (Sweden)

Julia Brailovskaia

Full Text Available Over one billion people use Facebook as a platform for social interaction and self-presentation making it one of the most popular online sites. The aim of the present study was to investigate differences in various personality traits and mental health variables between Facebook users and people who do not use this platform. The data of 945 participants (790 Facebook users, 155 Facebook non-users were collected. Results indicate that Facebook users score significantly higher on narcissism, self-esteem and extraversion than Facebook non-users. Furthermore, they have significantly higher values of social support, life satisfaction and subjective happiness. Facebook non-users have (marginally significantly higher values of depression symptoms than Facebook users. In both groups, extraversion, self-esteem, happiness, life satisfaction, resilience and social support, on the one hand, and depression, anxiety and stress symptoms, on the other hand, are negatively correlated. Neuroticism is positively associated with depression, anxiety and stress symptoms. However, significant differences exist between Facebook users and Facebook non-users regarding some associations of personality traits and mental health variables. Compared to Facebook non-users, the present results indicate that Facebook users have higher values of certain personality traits and positive variables protecting mental health. These findings are of particular interest considering the high importance of social online-platforms in the daily life of many people.

Human motion retrieval from hand-drawn sketch.

Science.gov (United States)

Chao, Min-Wen; Lin, Chao-Hung; Assa, Jackie; Lee, Tong-Yee

2012-05-01

The rapid growth of motion capture data increases the importance of motion retrieval. The majority of the existing motion retrieval approaches are based on a labor-intensive step in which the user browses and selects a desired query motion clip from the large motion clip database. In this work, a novel sketching interface for defining the query is presented. This simple approach allows users to define the required motion by sketching several motion strokes over a drawn character, which requires less effort and extends the users’ expressiveness. To support the real-time interface, a specialized encoding of the motions and the hand-drawn query is required. Here, we introduce a novel hierarchical encoding scheme based on a set of orthonormal spherical harmonic (SH) basis functions, which provides a compact representation, and avoids the CPU/processing intensive stage of temporal alignment used by previous solutions. Experimental results show that the proposed approach can well retrieve the motions, and is capable of retrieve logically and numerically similar motions, which is superior to previous approaches. The user study shows that the proposed system can be a useful tool to input motion query if the users are familiar with it. Finally, an application of generating a 3D animation from a hand-drawn comics strip is demonstrated.

Prosthetic management of an ocular defect

Directory of Open Access Journals (Sweden)

Siddesh Kumar Chintal

2010-01-01

Full Text Available The disfigurement associated with the loss of an eye can cause significant physical and emotional problems. Various treatment modalities are available, one of which is implants. Although implant has a superior outcome, it may not be advisable in all patients due to economic factors. The present article describes the prosthetic management of an ocular defect with a custom-made ocular prosthesis.

LEUKOCYTE AND BACTERIA IMAGING IN PROSTHETIC JOINT INFECTION

NARCIS (Netherlands)

Glaudemans, Andor W. J. M.; Galli, Filippo; Pacilio, Marta; Signore, Alberto

2013-01-01

There has been a significant increase in the number of joint prosthesis replacements worldwide. Although relatively uncommon, complications can occur with the most serious being an infection. Various radiological and nuclear imaging techniques are available to diagnose prosthetic joint infections

Nuclear Medicine in Diagnosis of Prosthetic Valve Endocarditis: An Update

Science.gov (United States)

Musso, Maria; Petrosillo, Nicola

2015-01-01

Over the past decades cardiovascular disease management has been substantially improved by the increasing introduction of medical devices as prosthetic valves. The yearly rate of infective endocarditis (IE) in patient with a prosthetic valve is approximately 3 cases per 1,000 patients. The fatality rate of prosthetic valve endocarditis (PVE) remains stable over the years, in part due to the aging of the population. The diagnostic value of echocardiography in diagnosis is operator-dependent and its sensitivity can decrease in presence of intracardiac devices and valvular prosthesis. The modified Duke criteria are considered the gold standard for diagnosing IE; their sensibility is 80%, but in clinical practice their diagnostic accuracy in PVE is lower, resulting inconclusively in nearly 30% of cases. In the last years, these new imaging modalities have gained an increasing attention because they make it possible to diagnose an IE earlier than the structural alterations occurring. Several studies have been conducted in order to assess the diagnostic accuracy of various nuclear medicine techniques in diagnosis of PVE. We performed a review of the literature to assess the available evidence on the role of nuclear medicine techniques in the diagnosis of PVE. PMID:25695043

The effects of a controlled energy storage and return prototype prosthetic foot on transtibial amputee ambulation.

Science.gov (United States)

Segal, Ava D; Zelik, Karl E; Klute, Glenn K; Morgenroth, David C; Hahn, Michael E; Orendurff, Michael S; Adamczyk, Peter G; Collins, Steven H; Kuo, Arthur D; Czerniecki, Joseph M

2012-08-01

The lack of functional ankle musculature in lower limb amputees contributes to the reduced prosthetic ankle push-off, compensations at other joints and more energetically costly gait commonly observed in comparison to non-amputees. A variety of energy storing and return prosthetic feet have been developed to address these issues but have not been shown to sufficiently improve amputee biomechanics and energetic cost, perhaps because the timing and magnitude of energy return is not controlled. The goal of this study was to examine how a prototype microprocessor-controlled prosthetic foot designed to store some of the energy during loading and return it during push-off affects amputee gait. Unilateral transtibial amputees wore the Controlled Energy Storage and Return prosthetic foot (CESR), a conventional foot (CONV), and their previously prescribed foot (PRES) in random order. Three-dimensional gait analysis and net oxygen consumption were collected as participants walked at constant speed. The CESR foot demonstrated increased energy storage during early stance, increased prosthetic foot peak push-off power and work, increased prosthetic limb center of mass (COM) push-off work and decreased intact limb COM collision work compared to CONV and PRES. The biological contribution of the positive COM work for CESR was reduced compared to CONV and PRES. However, the net metabolic cost for CESR did not change compared to CONV and increased compared to PRES, which may partially reflect the greater weight, lack of individualized size and stiffness and relatively less familiarity for CESR and CONV. Controlled energy storage and return enhanced prosthetic push-off, but requires further design modifications to improve amputee walking economy. Published by Elsevier B.V.

The influence of staff training and education on prosthetic and orthotic service quality: A scoping review.

Science.gov (United States)

Forghany, Saeed; Sadeghi-Demneh, Ebrahim; Trinler, Ursula; Onmanee, Pornsuree; Dillon, Michael P; Baker, Richard

2018-06-01

Education and training in prosthetics and orthotics typically comply with International Society for Prosthetics and Orthotics standards based on three categories of prosthetic and orthotic professionals. This scoping study sought to describe the evidence base available to answer the question, How are prosthetic and orthotic services influenced by the training of staff providing them? Scoping review. A structured search of the peer-reviewed literature catalogued in major electronic databases yielded 3039 papers. Following review of title and abstract, 93 articles were considered relevant. Full-text review reduced this number to 25. Only two articles were identified as providing direct evidence of the effects of training and education on service provision. While both suggested that there was an impact, it is difficult to see how the more specific conclusions of either could be generalised. The other 23 articles provide a useful background to a range of issues including the specification of competencies that training programmes should deliver (3 articles), descriptions of a range of training programmes and the effects of training and education on student knowledge and skills. Although it is considered axiomatic, the service quality is dependent on practitioner education and training. There is insufficient evidence to establish whether levels of training and education in prosthetics and orthotics have an effect on the quality of prosthetic and orthotic services. Clinical relevance There is very little evidence about the effects of training and education of prosthetists and orthotists on service quality. While this is a somewhat negative finding, we feel that it is important to bring this to the attention of the prosthetics and orthotics community.

Touch-less interaction with medical images using hand & foot gestures

DEFF Research Database (Denmark)

Jalaliniya, Shahram; Smith, Jeremiah; Sousa, Miguel

2013-01-01

control. In this paper, we present a system for gesture-based interaction with medical images based on a single wristband sensor and capacitive floor sensors, allowing for hand and foot gesture input. The first limited evaluation of the system showed an acceptable level of accuracy for 12 different hand...... & foot gestures; also users found that our combined hand and foot based gestures are intuitive for providing input....

Design of a wearable hand exoskeleton for exercising flexion/extension of the fingers.

Science.gov (United States)

Jo, Inseong; Lee, Jeongsoo; Park, Yeongyu; Bae, Joonbum

2017-07-01

In this paper, design of a wearable hand exoskeleton system for exercising flexion/extension of the fingers, is proposed. The exoskeleton was designed with a simple and wearable structure to aid finger motions in 1 degree of freedom (DOF). A hand grasping experiment by fully-abled people was performed to investigate general hand flexion/extension motions and the polynomial curve of general hand motions was obtained. To customize the hand exoskeleton for the user, the polynomial curve was adjusted to the joint range of motion (ROM) of the user and the optimal design of the exoskeleton structure was obtained using the optimization algorithm. A prototype divided into two parts (one part for the thumb, the other for rest fingers) was actuated by only two linear motors for compact size and light weight.

Towards Gesture-Based Multi-User Interactions in Collaborative Virtual Environments

Science.gov (United States)

Pretto, N.; Poiesi, F.

2017-11-01

We present a virtual reality (VR) setup that enables multiple users to participate in collaborative virtual environments and interact via gestures. A collaborative VR session is established through a network of users that is composed of a server and a set of clients. The server manages the communication amongst clients and is created by one of the users. Each user's VR setup consists of a Head Mounted Display (HMD) for immersive visualisation, a hand tracking system to interact with virtual objects and a single-hand joypad to move in the virtual environment. We use Google Cardboard as a HMD for the VR experience and a Leap Motion for hand tracking, thus making our solution low cost. We evaluate our VR setup though a forensics use case, where real-world objects pertaining to a simulated crime scene are included in a VR environment, acquired using a smartphone-based 3D reconstruction pipeline. Users can interact using virtual gesture-based tools such as pointers and rulers.

Impact of pannus formation on hemodynamic dysfunction of prosthetic aortic valve: pannus extent and its relationship to prosthetic valve motion and degree of stenosis.

Science.gov (United States)

Koo, Hyun Jung; Ha, Hojin; Kang, Joon-Won; Kim, Jeong A; Song, Jae-Kwan; Kim, Hwa Jung; Lim, Tae-Hwan; Yang, Dong Hyun

2018-02-19

Although pannus is an important cause of prosthetic valve dysfunction, the minimum pannus size that can induce hemodynamic dysfunction has not yet been determined. This study investigated the correlation between the limitation of motion (LOM) of the prosthetic valve and pannus extent and determined the pannus extent that could induce severe aortic stenosis. This study included 49 patients who underwent mechanical aortic valve replacement (AVR) and showed pannus on cardiac computed tomography (CT). Pannus width, ratio of pannus width to valve diameter, pannus area, effective orifice area, encroachment ratio by pannus, pannus involvement angle and percent LOM of mechanical valves were evaluated on CT. Transvalvular peak velocity (TPV) and transvalvular pressure gradient (TPG) were measured by transesophageal echocardiography to determine the degree of aortic stenosis. The relationship between percent LOM of the prosthetic valve and pannus extent and the cut-off of pannus extent required to induce severe aortic stenosis were evaluated. The mean interval between AVR and pannus formation was 11 years and was longer in patients with than without severe aortic stenosis (14.0 vs. 7.3 years). On CT, the percent LOM of the prosthetic valve was significantly associated with the extent of pannus only in patients with pannus involvement angle > 180° (r = 0.55-0.68, P Pannus width, effective orifice area, and encroachment ratio were significantly associated with increased TPV and TPG (r = 0.51-0.62, P Pannus width > 3.5 mm, pannus width/valve inner diameter > 0.15, and encroachment ratio > 0.14 were significantly associated with severe aortic stenosis (TPV > 4 m/s; mean TPG ≥ 35 mmHg), with c-indices of 0.74-079 (P pannus extent parameters are good indicators of significant hemodynamic changes with increased TPV and mean TPG.

The clinical significance of perivalvular pannus in prosthetic mitral valves: Can cardiac CT be helpful?

Science.gov (United States)

Chang, Suyon; Suh, Young Joo; Han, Kyunghwa; Kim, Jin Young; Kim, Young Jin; Chang, Byung-Chul; Choi, Byoung Wook

2017-12-15

The clinical significance of pannus in the prosthetic mitral valve (MV) is not well documented. To investigate the clinical significance of pannus on cardiac computed tomography (CT) in patients with a prosthetic MV. A total of 130 patients with previous MV replacement who underwent cardiac CT were retrospectively included in this study. The presence of pannus, paravalvular leak (PVL) around the prosthetic MV and limitation of motion (LOM) of the MV were analyzed using CT. Between patients with MV pannus and those without pannus, CT, echocardiographic, and redo-surgery findings were compared. The diagnostic performance of CT and transesophageal echocardiography (TEE) for the detection of MV pannus was also compared, using surgical findings as a standard reference. MV pannus was observed on cardiac CT in 32.3% of the study population. Patients with MV pannus detected on CT more commonly had LOM (28.2% vs. 15.2%) and less frequently had PVL of the prosthetic MV (16.7% vs. 25%) than patients without MV pannus (P>0.05). Prosthetic valve obstruction (PVO) due prosthetic MV pannus requiring redo-surgery was present in only five patients (11.9%). Cardiac CT detected MV pannus with sensitivity of 65.2% and specificity of 80.9% and showed better diagnostic performance than TEE (Ppannus can frequently be seen on cardiac CT. However, its clinical significance should be assessed with careful consideration, because PVO due to MV pannus is relatively uncommon, and pannus can be seen in patients without any clinical problems. Copyright © 2017 Elsevier B.V. All rights reserved.

An evaluation of prosthetic status and treatment needs among institutionalized elderly individuals of Delhi, India

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Nisha Yadav

2017-01-01

Full Text Available Context: Oral health is essential for elderly person's general health and well-being. The most common oral problem in elderly is tooth loss which results due to periodontal diseases and caries. Prosthetic status is very important as it is related to dietary intake and maintaining nutritional status. Hence, to promote the oral health of the elderly, we need to know their prosthetic status and need. Aims: The aim of this study is to find the prosthetic status and need of 65–74 years old elderly residing in old age homes of Delhi, India. Settings and Design: A cross-sectional study was conducted among a total of 464 residents of 20 old age homes of Delhi, India. Material and Methods: Residents with age group of 64–75 were included in the study. The prosthetic status with treatment need was recorded using the World Health Organization Oral Health Assessment Form (1997. Statistical Analysis Used: Chi-square test and t-test were used to find significance of variables. P < 0.05 was considered significant. Results: Full removable dentures were worn by 7.30% of participants with predominance in upper arch, and one bridge was seen in 9.10% of participants with predominance in lower arch. Full removable denture was required in 25.20% of participants. Most of participants required multiunit prosthesis in both upper as well as lower arch (42.20% and 36.20%, respectively. Conclusion: The present study underlines a considerable need for dental treatment in elderly as the prosthetic status of participants was poor, and prosthetic needs were high.

Prosthetic Smart Socket Technology to Improve Patient Interaction, Usability, Comfort, Fit and Function

Science.gov (United States)

2017-10-01

impact on society beyond science and technology ? Nothing to report at this time. 5. CHANGES/PROBLEMS: Changes in approach and reasons for...AWARD NUMBER: W81XWH-16-1-0785 TITLE: Prosthetic Smart Socket Technology to Improve Patient Interaction, Usability, Comfort, Fit and Function...2016 - 29 Sep 2017 4. TITLE AND SUBTITLE Prosthetic Smart Socket Technology to Improve Patient Interaction, Usability, Comfort, Fit and Function 5a

Multi-Disciplinary Antimicrobial Strategies for Improving Orthopaedic Implants to Prevent Prosthetic Joint Infections in Hip and Knee

Science.gov (United States)

Getzlaf, Matthew A.; Lewallen, Eric A.; Kremers, Hilal M.; Jones, Dakota L.; Bonin, Carolina A.; Dudakovic, Amel; Thaler, Roman; Cohen, Robert C.; Lewallen, David G.; van Wijnen, Andre J.

2016-01-01

Like any foreign object, orthopaedic implants are susceptible to infection when introduced into the human body. Without additional preventative measures, the absolute number of annual prosthetic joint infections will continue to rise, and may exceed the capacity of health care systems in the near future. Bacteria are difficult to eradicate from synovial joints due to their exceptionally diverse taxonomy, complex mechanistic attachment capabilities, and tendency to evolve antibiotic resistance. When a primary orthopaedic implant fails from prosthetic joint infection, surgeons are generally challenged by limited options for intervention. In this review, we highlight the etiology and taxonomic groupings of bacteria known to cause prosthetic joint infections, and examine their key mechanisms of attachment. We propose that antimicrobial strategies should focus on the most harmful bacteria taxa within the context of occurrence, taxonomic diversity, adhesion mechanisms, and implant design. Patient-specific identification of organisms that cause prosthetic joint infections will permit assessment of their biological vulnerabilities. The latter can be targeted using a range of antimicrobial techniques that exploit different colonization mechanisms including implant surface attachment, biofilm formation, and/or hematogenous recruitment. We anticipate that customized strategies for each patient, joint, and prosthetic component will be most effective at reducing prosthetic joint infections, including those caused by antibiotic-resistant and polymicrobial bacteria. PMID:26449208

Load-Bearing Capacity and Retention of Newly Developed Micro-Locking Implant Prosthetic System: An In Vitro Pilot Study

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Jae-Won Choi

2018-04-01

Full Text Available The aim of this study was to introduce the newly developed micro-locking implant prosthetic system and to evaluate the resulting its characteristics. To evaluate load-bearing capacity, 25 implants were divided into five groups: external-hexagon connection (EH, internal-octagon connection (IO, internal-hexagon connection (IH, one-body implant (OB, micro-locking implant system (ML. The maximum compressive load was measured using a universal testing machine (UTM according to the ISO 14801. Retention was evaluated in two experiments: (1 a tensile test of the structure modifications of the components (attachment and implant and (2 a tensile test after cyclic loading (total 5,000,000 cycles, 100 N, 2 Hz. The load-bearing capacity of the ML group was not significantly different from the other groups (p > 0.05. The number of balls in the attachment and the presence of a hexagonal receptacle did not show a significant correlation with retention (p > 0.05, but the shape of the retentive groove in the implant post had a statistically significant effect on retention (p < 0.05. On the other hand, the retention loss was observed during the initial 1,000,000 cycles, but an overall constant retention was maintained afterward. Various preclinical studies on this novel micro-locking implant prosthetic system should continue so that it can be applied in clinical practice.

Obstructed bi-leaflet prosthetic mitral valve imaging with real-time three-dimensional transesophageal echocardiography.

Science.gov (United States)

Shimbo, Mai; Watanabe, Hiroyuki; Kimura, Shunsuke; Terada, Mai; Iino, Takako; Iino, Kenji; Ito, Hiroshi

2015-01-01

Real-time three-dimensional transesophageal echocardiography (RT3D-TEE) can provide unique visualization and better understanding of the relationship among cardiac structures. Here, we report the case of an 85-year-old woman with an obstructed mitral prosthetic valve diagnosed promptly by RT3D-TEE, which clearly showed a leaflet stuck in the closed position. The opening and closing angles of the valve leaflets measured by RT3D-TEE were compatible with those measured by fluoroscopy. Moreover, RT3D-TEE revealed, in the ring of the prosthetic valve, thrombi that were not visible on fluoroscopy. RT3D-TEE might be a valuable diagnostic technique for prosthetic mitral valve thrombosis. © 2014 Wiley Periodicals, Inc.

Can we close large prosthetic space with orthodontics?

Science.gov (United States)

Mesko, Mauro Elias; Skupien, Jovito Adiel; Valentini, Fernanda; Pereira-Cenci, Tatiana

2013-01-01

For years, the treatment for the replacement of a missing tooth was a fixed dental prosthesis. Currently, implants are indicated to replace missing teeth due to high clinical success and with the advantage of not performing preparations in the adjacent tooth. Another option for space closure is the use of orthodontics associated to miniscrews for anchorage allowing better control of the orthodontic biomechanics and especially making possible closure of larger prosthetic spaces. Thus, this article describes two cases with indications and discussion of the advantages and disadvantages of using orthodontics for prosthetic spaces closure. The cases herein presented show that it is possible to close an space when there are available teeth in the adjacent area. It can be concluded that when a malocclusion is present there will be a strong trend to indicate space closure by orthodontic movement as it preserves natural teeth and seems a more physiological approach.

The History of Nontraditional or Ectopic Placement of Reservoirs in Prosthetic Urology.

Science.gov (United States)

Perito, Paul; Wilson, Steven

2016-04-01

Reservoir placement during implantation of prosthetic urology devices has been problematic throughout the history of the surgical treatment of erectile dysfunction and urinary incontinence. We thought it would be interesting to review the history of reservoir placement leading up to current surgical techniques. To provide an overview of the past and present techniques for reservoir placement and discuss the evolutionary process leading to safe and effective placement of prosthetic reservoirs. We reviewed data pertaining to inflatable penile prosthesis (IPP) reservoirs and pressure-regulating balloons (PRB) in a chronological fashion, spanning 25 years. Main outcomes included a historical review of techniques for IPP reservoir and PRB placement leading to the subsequent incremental improvements in safety and efficacy when performing penile implants and artificial urinary sphincters. Prosthetic urologic reservoirs have traditionally been placed in the retropubic space. Over the years, urologists have attempted use of alternative spaces including peritoneal, epigastric, "ectopic," posterior to transversalis, and high submuscular. Current advances in prosthetic urologic reservoir placement allow safe and effective abdominal wall placement of reservoirs. These novel approaches appear to be so effective that urologists may now be able to cease using the traditional retropubic space for reservoir placement, even in the case of virgin pelves. Copyright © 2016 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Comparing Facebook Users and Facebook Non-Users: Relationship between Personality Traits and Mental Health Variables – An Exploratory Study

Science.gov (United States)

2016-01-01

Over one billion people use Facebook as a platform for social interaction and self-presentation making it one of the most popular online sites. The aim of the present study was to investigate differences in various personality traits and mental health variables between Facebook users and people who do not use this platform. The data of 945 participants (790 Facebook users, 155 Facebook non-users) were collected. Results indicate that Facebook users score significantly higher on narcissism, self-esteem and extraversion than Facebook non-users. Furthermore, they have significantly higher values of social support, life satisfaction and subjective happiness. Facebook non-users have (marginally) significantly higher values of depression symptoms than Facebook users. In both groups, extraversion, self-esteem, happiness, life satisfaction, resilience and social support, on the one hand, and depression, anxiety and stress symptoms, on the other hand, are negatively correlated. Neuroticism is positively associated with depression, anxiety and stress symptoms. However, significant differences exist between Facebook users and Facebook non-users regarding some associations of personality traits and mental health variables. Compared to Facebook non-users, the present results indicate that Facebook users have higher values of certain personality traits and positive variables protecting mental health. These findings are of particular interest considering the high importance of social online-platforms in the daily life of many people. PMID:27907020

[Microbiological characteristics and patterns of resistance in prosthetic joint infections in a referral hospital].

Science.gov (United States)

Ortega-Peña, Silvestre; Colín-Castro, Claudia; Hernández-Duran, Melissa; López-Jácome, Esaú; Franco-Cendejas, Rafael

2015-01-01

The prosthetic joint infection is the most feared and catastrophic complication for cause severe physical damage to patients and, generates high economic costs. To describe the microbiological characteristics and to determine the resistance pattern in prosthetic joint infections in a reference hospital in Mexico. Patients whose prosthetic devices were withdrawn due to suspicion of septic and aseptic loosening were included. Cultures were performed to identify microorganisms and susceptibility analysis. Of the 111 patients included, 55% were diagnosed with prosthetic joint infection, with the most frequent prosthesis being of the hip (43%). Positive cultures were obtained in 97% of the infected cases, of which 75% were monomicrobial infections. The most frequent bacterial species isolated were: Staphylococcus epidermidis (31%), Enterococcus faecalis (16%), Staphylococcus aureus (13%), and Escherichia coli (8%). The resistance patterns for the Staphylococcus genus were: oxacillin (79%), erythromycin (45%) and ciprofloxacin (37%). Enterococcus faecalis showed a high percentage of resistance to erythromycin and clindamycin (86%), and fluoroquinolones (43%). The large majority (86%) of Escherichia coli were extended spectrum beta-lactamases positive, in addition to having high resistance to fluoroquinolones (86%), trimethoprim/sulfamethoxazole (86%) and gentamicin (72%). The microbiological characteristics found in prosthetic joint infections vary according to the hospitals. In this series, a high proportion of coagulase-negative Staphylococci and Enterococcus spp. were found, as well as a high bacterial resistance. Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.

Prosthetic joint infection caused by Granulicatella adiacens: a case series and review of literature.

Science.gov (United States)

Quénard, Fanny; Seng, Piseth; Lagier, Jean-Christophe; Fenollar, Florence; Stein, Andreas

2017-06-23

Bone and joint infection involving Granulicatella adiacens is rare, and mainly involved in cases of bacteremia and infectious endocarditis. Here we report three cases of prosthetic joint infection involving G. adiacens that were successfully treated with surgery and prolonged antimicrobial treatment. We also review the two cases of prosthetic joint infection involving G. adiacens that are reported in the literature. Not all five cases of prosthetic joint infection caused by G. adiacens were associated with bacteremia or infectious endocarditis. Dental care before the onset of infection was observed in two cases. The median time delay between arthroplasty implantation and the onset of infection was of 4 years (ranging between 2 and 10 years). One of our cases was identified with 16srRNA gene sequencing, one case with MALDI-TOF mass spectrometry, and one case with both techniques. Two literature cases were diagnosed by 16srRNA gene sequencing. All five cases were cured after surgery including a two-stage prosthesis exchange in three cases, a one-stage prosthesis exchange in one case, and debridement, antibiotics, irrigation, and retention of the prosthesis in one case, and prolonged antimicrobial treatment. Prosthetic joint infection involving G. adiacens is probably often dismissed due to difficult culture or misdiagnosis, in particular in the cases of polymicrobial infection. Debridement, antibiotics, irrigation, and retention of the prosthesis associated with prolonged antimicrobial treatment (≥ 8 weeks) should be considered as a treatment strategy for prosthetic joint infection involving G. adiacens.

[Intra-prosthetic dislocation of the Bousquet dual mobility socket].

Science.gov (United States)

Lecuire, F; Benareau, I; Rubini, J; Basso, M

2004-05-01

The Bousquet system is a dual mobility head-polyethylene polyethylene-metal cup socket. The polyethylene insert retaining the femoral head moves in the noncemented metal cup, increasing both mobility and stability. Between 1989 and 1997, seven cases of intra-prosthetic dislocation (six patients) were observed. The femoral head escaped from the polyethylene insert due to wear. On the average, this complication occurred ten Years after implantation. Risk of dislocation was high in six of the seven hips. All patients had a large sized stem screwed into the femoral neck. There was a characteristic radiological aspect with loss of the concentric head metal cup configuration. The head was applied against the upper wall of the metal cup. Surgical replacement was undertaken early in six patients by simply changing the insert without modifying the other stable components. Outcome remained good at three to eight Years. One patient underwent late surgery. The insert and the cup were replaced with a classical implant. Functional outcome was good but recurrent dislocation occurred. At mid-term, intra-prosthetic dislocation of dual mobility sockets appears to be exceptional. Dislocation results from polyethylene wear leading to failure of the insert to retain the prosthetic head. Wear is favored by direct phenomena (direct contact between neck and insert which can occur early if there is a small difference in the head and neck diameters) or indirect phenomena (factors limiting polyethylene metal-cup mobility). Surgical treatment is necessary. If undertaken early, replacement with a modular head and insert can be sufficient if the prosthesis has not loosened but the metal cup may have to be replaced in the event of metal-metal contact between the head and the cup. Prosthesis loosening, wear of the metal cup, or an identified cause of dislocation imply replacing the failing implants. Implantation of the dual mobility system is particularly interesting for patients with a high risk

Extrinsic mechanism obstructing the opening of a prosthetic mitral valve: an unusual case of suture entrapment.

Science.gov (United States)

Ozkan, Mehmet; Astarcioglu, Mehmet Ali; Karakoyun, Suleyman; Balkanay, Mehmet

2012-02-01

Obstruction to a prosthetic cardiac valve is a well-recognized complication of cardiac valve replacement. Malfunction of the mobile component of a prosthetic valve to open or close correctly may occur in consequence of intrinsic or extrinsic causes (thrombus, vegetation, entrapment of left ventricular myocardium, suture entanglement, and pannus formation) that may result prosthetic valve stenosis and/or insufficiency. In the case we report a 48-year-old female with valve dysfunction occurred early after surgery, as one valve leaflet was only able to partially open due to suture entrapment. © 2011, Wiley Periodicals, Inc.

Prosthetic Management of Patients Presenting with Juvenile ...

African Journals Online (AJOL)

Eighteen were referred for prosthetic replacement. Their age ranged between 18 and 36 years. A total of 24 removable partial dentures were fabricated, 17[70.8%] were kennedy class III type, of which 11[64.7%] had the bounded saddle located in the anterior segment. Majority 8[44.4%] of the patients had 2-4 teeth replaced ...

Pseudotumor of the Hip due to Fungal Prosthetic Joint Infection

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Stefano Artiaco

2013-01-01

Full Text Available Pseudotumors associated with total hip arthroplasty have been associated with metal-on-metal and metal-on-polyethylene total hip arthroplasties due to a granulomatous foreign-body reaction to methyl methacrylate, polyethylene, or metal ion release, but they have not been related to prosthetic joint infections. In this paper, we report an unusual case of Candida albicans total hip arthroplasty infection, causing a large inflammatory pseudotumor of the hip joint. Fungal periprosthetic joint infections are a rare clinical entity and difficult to diagnose, and a pseudotumor may be part of their clinical presentation. They should be suspected in immunodeficient host patients when clinical symptoms of prosthetic joint infections are observed.

Retrieval of a leaflet escaped in a Tri-technologies bileaflet mechanical prosthetic valve.

Science.gov (United States)

Cianciulli, Tomás F; Lax, Jorge A; Saccheri, María C; Guidoin, Robert; Salvado, César M; Fernández, Adrián J; Prezioso, Horacio A

2008-01-01

The escape of the prosthetic heart valve disc is one of the causes of prosthetic dysfunction that requires emergency surgery. The removal of the embolized disc should be carried out because of the risk of a progressive extrusion on the aortic wall. Several imaging techniques can be used for the detection of the missing disc localization. In this report we describe a 32-year-old man who underwent mitral valve replacement with a Tri-technologies bileaflet valve three years ago, and was admitted in cardiogenic shock. Transesophageal echocardiography showed acute-onset massive mitral regurgitation. The patient underwent emergency replacement of the prosthetic valve. Only one of the two leaflets remained in the removed prosthetic valve. The missing leaflet could not be found within the cardiac cavity. The abdominal fluoroscopic study and plain radiography were unable to detect the escaped leaflet. The abdominal computed tomography scan and the ultrasound showed the escaped leaflet in the terminal portion of the aortic bifurcation. To retrieve the embolized disc laparotomy and aortotomy were performed three months later. The escaped leaflet shows a fracture of one of the pivot systems caused by structural failure. This kind of failure mode is usually the result of high stress concentration.

A geometrical optimization of a magneto-rheological rotary brake in a prosthetic knee

International Nuclear Information System (INIS)

Gudmundsson, K H; Jonsdottir, F; Thorsteinsson, F

2010-01-01

Magneto-rheological (MR) fluids have been successfully introduced to prosthetic devices. One such device is a biomechanical prosthetic knee that uses MR fluids to actively control its rotary stiffness. The brake is rotational, utilizing the MR fluid in shear mode. In this study, the geometrical design of the MR brake is addressed. This includes the design of the magnetic circuit and the geometry of the fluid chamber. Mathematical models are presented that describe the rotary torque of the brake. A novel perfluorinated polyether (PFPE)-based MR fluid is introduced, whose properties are tailored for the prosthetic knee. On-state and off-state rheological measurements of the MR fluid are presented. The finite element method is used to evaluate the magnetic flux density in the MR fluid. The design is formulated as an optimization problem, aiming to maximize the braking torque. A parametric study is carried out for several design parameters. Subsequently, a multi-objective optimization problem is defined that considers three design objectives: the field-induced braking torque, the off-state rotary stiffness and the weight of the brake. Trade-offs between the three design objectives are investigated which provides a basis for informed design decisions on furthering the success of the MR prosthetic knee

Prosthetic joint infection due to Lysobacter thermophilus diagnosed by 16S rRNA gene sequencing

OpenAIRE

B Dhawan; S Sebastian; R Malhotra; A Kapil; D Gautam

2016-01-01

We report the first case of prosthetic joint infection caused by Lysobacter thermophilus which was identified by 16S rRNA gene sequencing. Removal of prosthesis followed by antibiotic treatment resulted in good clinical outcome. This case illustrates the use of molecular diagnostics to detect uncommon organisms in suspected prosthetic infections.

Scintigraphic detection of prosthetic joint and soft tissue sepsis secondary to tuberculosis

International Nuclear Information System (INIS)

Zeiger, L.S.; Watters, W.; Sherk, H.

1984-01-01

In a 40-year-old Hispanic woman with pain and swelling in the left knee with a prosthesis, the combination of Ga-67 citrate and Tc-99m methylene diphosphonate (MDP) scans was used to indicate that there was a septic prosthetic joint. At surgery, the joint was infected and a foreign body was found. Cultures positive for tuberculosis were found also. The presence of an incongruent Ga-67 and Tc-99m (MDP) scan pattern suggests infection of the prosthetic joint, as in the following case

Prosthetic prescription in the Netherlands : an observational study

NARCIS (Netherlands)

van der Linde, H; Geertzen, JHB; Hofstad, CJ; Postema, K; Van Limbeek, Jacques

2003-01-01

Prosthetic prescription for lower limb amputees and the methodology used are primarily based on empirical knowledge. Clinical expertise plays an important role that can lead to an adequate prescription; however, a clear evidence based motivation for the choices made cannot be given. This can lead to

Resource-efficient proces chains to manufacture patient-specific prosthetic fingers

Directory of Open Access Journals (Sweden)

Hagedorn-Hansen, D.

2016-05-01

Full Text Available The high cost of quality prostheses, together with the lack of trained prosthetists, makes it challenging to obtain prosthetic devices in developing communities. Modern 3D digitising techniques and additive manufacturing (AM technologies are gaining popularity in the bio-medical industry and, in the case of prosthesis production, reduce the need for a trained prosthetist. The objective of this research was to develop a new resource-efficient process chain for the manufacturing of prosthetic fingers using additive manufacturing technologies, and to compare it with the traditional (Sculptor process chain. Fused deposition modelling (FDM, open-source FDM, 3-dimensional printing (3DP, and stereolithography (SLA were evaluated in terms of their costs, time, material usage, and aesthetic quality. The surface qualities produced with the different additive manufacturing technologies were also compared. The results showed that 3DP was the preferred technology and was the best candidate for the production of prosthesis in terms of cost, quality, and time for developing communities. SLA produced the highest aesthetic quality prosthesis, but was the most expensive. It was concluded that using the additive manufacturing technology process chain to produce prosthetic fingers is faster and more cost effective than the traditional method.

Simulation Techniques and Prosthetic Approach Towards Biologically Efficient Artificial Sense Organs- An Overview

OpenAIRE

Neogi, Biswarup; Ghosal, Soumya; Mukherjee, Soumyajit; Das, Achintya; Tibarewala, D. N.

2011-01-01

An overview of the applications of control theory to prosthetic sense organs including the senses of vision, taste and odor is being presented in this paper. Simulation aspect nowadays has been the centre of research in the field of prosthesis. There have been various successful applications of prosthetic organs, in case of natural biological organs dis-functioning patients. Simulation aspects and control modeling are indispensible for knowing system performance, and to generate an original a...

The use of ceramic in prosthetic hip surgery. The state of the art.

Science.gov (United States)

Toni, A; Terzi, S; Sudanese, A; Tabarroni, M; Zappoli, F A; Stea, S; Giunti, A

1995-01-01

The authors review current knowledge regarding the use of ceramic materials in prosthetic hip surgery, both as constituents of prosthetic components, and as materials used to coat metallic surfaces. A review of the literature defines the advantages and disadvantages to using ceramic-polyethylene or ceramic-ceramic combinations, based on the possibility that alumina coating may favor localized bone demineralization, and on the first promising clinical results of the use of hydroxyapatite coating.

Indium-granulocyte scanning in the painful prosthetic joint

International Nuclear Information System (INIS)

Pring, D.J.; Henderson, R.G.; Keshavarzian, A.; Rivett, A.G.; Krausz, T.; Coombs, R.R.; Lavender, J.P.

1986-01-01

The value of indium-111-labeled granulocyte scanning to determine the presence of infection was assessed in 50 prosthetic joints (41 of which were painful) in 40 patients. Granulocytes were obtained from the patients' blood and labeled in plasma with indium 111 tropolonate. Abnormal accumulation of indium 111 in the region of the prosthesis was noted. Proven infection occurred in 11 prostheses, and all of the infections were detected by indium-111-labeled granulocyte scanning. Nineteen were not infected (including nine asymptomatic controls) and only two produced false-positive scans. This represents a specificity of 89.5%, sensitivity of 100%, and overall accuracy of 93.2%. These results compare favorably with plain radiography. There was no radiologic evidence of infection in three of the infected prostheses, and 10 of the noninfected prostheses had some radiologic features that suggested sepsis. We conclude that indium-granulocyte scanning can reliably detect or exclude infection in painful prosthetic joints and should prove useful in clinical management

A new concept in biometric identification 3-dimensional hand geometry

International Nuclear Information System (INIS)

Sidlauskas, D.P.

1987-01-01

A new type of biometric identifier which utilizes hand outline measurements made in three dimensions is described. This device uses solid state imaging with no moving parts. The important characteristics of accuracy, speed, user tolerability, small template size, low power, portability and reliability are discussed. A complete stand-alone biometric access control station with sufficient memory for 10,000 users and weighing less than 10 pounds has been built and tested. A test was conducted involving daily use by 112 users over a seven week period during which over 6300 access attempts were made. The single try equal error rate was found to be 0.4%. There were no false rejects when three tries were allowed before access was denied. Defeat with an artifact is difficult because the hand must be copied in all three dimensions

CT Assessment of the axial deviation of the femoral and tibial prosthetic components in total knee arthroplasty

International Nuclear Information System (INIS)

Rimondi, E.; Molinari, M.; Moio, A.; Busacca, M.; Trentani, F.; Trentani, P.; Tigani, D.; Nigrosoli, M.

2000-01-01

CT assessment of the axial deviation of the femoral and tibial prosthetic components in total knee arthroplasty. From January to July 1999, 17 patients, 10 males and 7 females, mean age 66 years (standard deviation plus or minus 4) were examined after total knee arthroplasty. Exclusion criteriawere prosthesis loosening and severe (equal or superior to 7'' varus o valgus deviation. All patients were examined with knee radiography in the standing position completed by axial projection of patella and by CT scanning. It was used a modification of Berger technique and carried out comparative CT scans extended lower limbs and acquisitions perpendicular to the mechanical axis of the knee, from the femoral supracondylar region down to the plane crossing the distal end of the tibial prosthetic component. Reference lines were then drawn electronically on given scanning planes to reckon the axial deviation of the femoral and tibial prosthetic components. Six patients, one female and 5 males with normal rotational values of femoral and tibial prosthetic components presented no clinical symptoms. Eight patients, 4 females and 4 males, with abnormal values presented the following clinical symptoms: medial impingement, (incomplete) dislocation patella, and lateral instability. One female patient with a normal rotational value of femoral prosthetic component and an altered value of tibial prosthetic component presented medial impingement. Finally two patients, one female and one male, were absolutely asymptomatic although the rotational values of the two prosthetic components were beyond the normal range. Total knee arthroplasty is presently a standard treatment for many conditions involving this joint. There are several possible postoperative complications, namely fractures, dislocations (a)septic losening and femoropatellar instability. The latter condition is the most frequent complication among implant failures and is caused by bad orientation of the femoral and tibial

Orthodontic space closure versus prosthetic replacement of missing upper lateral incisors in patients with bilateral cleft lip and palate.

Science.gov (United States)

Oosterkamp, Barbara C M; Dijkstra, Pieter U; Remmelink, Hendrik J; van Oort, Robert P; Sandham, Andrew

2010-11-01

To compare dental aesthetics and function of orthodontic space closure versus prosthetic replacement of upper lateral incisors in patients with bilateral cleft lip and palate. The predominant mode of prosthetic replacement was resin-bonded bridges. The retrospective study group consisted of 17 patients treated with orthodontic space closure (13 men, four women; median age, 27.1 years; interquartile range, 20.6 to 33.3 years) and 10 patients treated with prosthetic replacement (five men, five women; median age, 27.7 years; interquartile range, 20.9 to 39.7 years). Dental aesthetics were evaluated by the patients and by a professional panel. Mandibular function was evaluated by means of the mandibular function impairment questionnaire. The level of mandibular impairment was calculated using the Function Impairment Rating Scale. With respect to dental aesthetics, no significant differences between patients treated with orthodontic space closure and prosthetic replacement were found. With respect to function, the level of mandibular impairment was significantly higher in patients treated with prosthetic replacement compared with patients treated with orthodontic space closure, as indicated by high scores on specific masticatory functions. Orthodontic space closure and prosthetic replacement in bilateral cleft lip and palate patients produce similar results in terms of aesthetics. In terms of function, prosthetic replacement results in significantly more impairment of specific masticatory functions.

User Experience Evaluation in the Mobile Context

Science.gov (United States)

Obrist, Marianna; Meschtscherjakov, Alexander; Tscheligi, Manfred

Multimedia services on mobile devices are becoming increasingly popular. Whereas the mobile phone is the most likely platform for mobile TV, PDAs, portable game consoles, and music players are attractive alternatives. Mobile TV consumption on mobile phones allows new kinds of user experiences, but it also puts designers and researchers in front of new challenges. On the one hand, designers have to take these novel experience potentials into account. On the other hand, the right methods to collect user feedback to further improve services for the mobile context have to be applied. In this chapter the importance of user experience research for mobile TV within the mobile context is highlighted. We present how different experience levels can be evaluated taking different mobile context categories into account. In particular, we discuss the Experience Sampling Method (ESM), which seems to be a fruitful approach for investigating user TV experiences.

Comparative study of radiography and scintigraphy for loosening and infection of prosthetic hip replacement

International Nuclear Information System (INIS)

Park, Mi Sook; Lee, Sun Wha; Choi, Woo Suk; Lim, Joo Won; Song, Han Joon; Ahn, Chi Yul

1987-01-01

Prosthetic hip replacement is associated with certain complications which result in a painful hip. Many of these, e. g. prosthetic dislocation, fracture, trochanteric avulsion, and heterotopic calcification are easily diagnosed by conventional radiography. However, radiographic evaluation for infection and/pr loosening of prosthesis as major complications requiring reoperation often contributes little to the resolution of the diagnostic problem. The authors made a comparative study of plain radiography and scintigraphy of 39 cases performed revision at Kyung Hee University Hospital from Sep. '81-to Aug. '86. The results were as follows: 1. In 39 revised prosthetic hip replacement, 26 cases (67%) of loosening without infection and 11 cases (28%) of infection were proven. 2. In loosening of prosthesis, plain radiography showed true positive rate of 76% and true negative rate of 60%, and scintigraphy showed true positive rate of 75% and true negative rate of 95%. 3. In infection of prosthesis, plain radiography revealed true positive rate of 55% and true negative rate of 96%, and scintigraphy revealed true positive rate of 100% and true negative rate of 83%. 4. Scintigraphy and plain radiography were useful as complementary procedure in evaluating and differentiating loosening and/or infection of prosthetic component

Case Study on Human Walking during Wearing a Powered Prosthetic Device: Effectiveness of the System “Human-Robot”

Directory of Open Access Journals (Sweden)

Svetlana Grosu

2014-01-01

Full Text Available It is known that force exchanges between a robotic assistive device and the end-user have a direct impact on the quality and performance of a particular movement task. This knowledge finds a special reflective importance in prosthetic industry due to the close human-robot collaboration. Although lower-extremity prostheses are currently better able to provide assistance as their upper-extremity counterparts, specific locomotion problems still remain. In a framework of this contribution the authors introduce the multibody dynamic modelling approach of the transtibial prosthesis wearing on a human body model. The obtained results are based on multibody dynamic simulations against the real experimental data using AMP-Foot 2.0, an energy efficient powered transtibial prosthesis for actively assisted walking of amputees.

Hand pose recognition in First Person Vision through graph spectral analysis

NARCIS (Netherlands)

Baydoun, Mohamad; Betancourt, Alejandro; Morerio, Pietro; Marcenaro, Lucio; Rauterberg, Matthias; Regazzoni, Carlo

2017-01-01

© 2017 IEEE. With the growing availability of wearable technology, video recording devices have become so intimately tied to individuals, that they are able to record the movements of users' hands, making hand-based applications one the most explored area in First Person Vision (FPV). In particular,

Periodic components of hand acceleration/deceleration impulses during telemanipulation

Energy Technology Data Exchange (ETDEWEB)

Draper, J.V. [Oak Ridge National Lab., TN (United States); Handel, S. [Tennessee Univ., Knoxville, TN (United States). Dept. of Psychology

1994-01-01

Responsiveness is the ability of a telemanipulator to recreate user trajectories and impedance in time and space. For trajectory production, a key determinant of responsiveness is the ability of the system to accept user inputs, which are forces on the master handle generated by user hand acceleration/deceleration (a/d) impulses, and translate them into slave arm acceleration/deceleration. This paper presents observations of master controller a/d impulses during completion of a simple target acquisition task. Power spectral density functions (PSDF`s) calculated from hand controller a/d impulses were used to assess impulse waveform. The relative contributions of frequency intervals ranging up to 25 Hz for three spatially different versions of the task were used to determine which frequencies were most important. The highest relative power was observed in frequencies between 1 Hz and 6 Hz. The key frequencies related to task difficulty were in the range from 2 Hz to 8 Hz. the results provide clues to the source of the performance inhibition.

Periodic components of hand acceleration/deceleration impulses during telemanipulation

International Nuclear Information System (INIS)

Draper, J.V.; Handel, S.

1994-01-01

Responsiveness is the ability of a telemanipulator to recreate user trajectories and impedance in time and space. For trajectory production, a key determinant of responsiveness is the ability of the system to accept user inputs, which are forces on the master handle generated by user hand acceleration/deceleration (a/d) impulses, and translate them into slave arm acceleration/deceleration. This paper presents observations of master controller a/d impulses during completion of a simple target acquisition task. Power spectral density functions (PSDF's) calculated from hand controller a/d impulses were used to assess impulse waveform. The relative contributions of frequency intervals ranging up to 25 Hz for three spatially different versions of the task were used to determine which frequencies were most important. The highest relative power was observed in frequencies between 1 Hz and 6 Hz. The key frequencies related to task difficulty were in the range from 2 Hz to 8 Hz. the results provide clues to the source of the performance inhibition

FACTORS RELATED TO ORAL CANDIDIASIS IN ELDERLY USERS AND NON-USERS OF REMOVABLE DENTAL PROSTHESES.

Science.gov (United States)

Bianchi, Cyra Maria Pires de Carvalho; Bianchi, Hélcio Aparecido; Tadano, Tomoko; Paula, Claudete Rodrigues de; Hoffmann-Santos, Hugo Dias; Leite, Diniz Pereira; Hahn, Rosane Christine

2016-01-01

This study examined the association between oral candidiasis in elderly users and nonusers of prosthesis and its predisposing factors. To this end, we performed a cross-sectional study where saliva samples from 48 patients were collected they used prosthesis and 43 patients (control group) who did not use. Among the 91 patients, Candida spp were isolated in 40 (83.3%) who used prosthesis and in 23 (53.5%) in the control group. A statistically significant association was determined between the two groups, the isolation of yeasts and dental prosthesis (p oral candidiasis (n = 24), 83.3% (n = 20) belonged to the group that wore dentures, while only 16.7% (n = 4) belonged to the control group. Elderly patients with diabetes had 4.4 times higher estimated risk of developing oral candidiasis when compared with individuals without this condition. There was no statistically significant association between being user prostheses and have diabetes with the onset of candidiasis. No statistically significant association was determined between xerostomia, use of prosthesis and oral candidiasis. The use of prosthetics and poor oral hygiene in elderly patients predisposes to the development of oral candidiasis.

Estimating volume, biomass, and potential emissions of hand-piled fuels

Science.gov (United States)

Clinton S. Wright; Cameron S. Balog; Jeffrey W. Kelly

2009-01-01

Dimensions, volume, and biomass were measured for 121 hand-constructed piles composed primarily of coniferous (n = 63) and shrub/hardwood (n = 58) material at sites in Washington and California. Equations using pile dimensions, shape, and type allow users to accurately estimate the biomass of hand piles. Equations for estimating true pile volume from simple geometric...

METHODOLOGY OF PROSTHETIC TREATMENT IN PATIENTS WITH MAXILLECTOMY

Directory of Open Access Journals (Sweden)

Ivan Gerdzhikov

2018-06-01

Full Text Available Aim: The aim of the described method is to present the main stages in the prosthetic treatment with hollow bulb obturator, which provides optimum defect hermetization and restoration of the damaged functions. Materials and methods: The clinical case, described is on a 70-years-old patient with edentulous jaws and maxillary defect in the right half of the upper jaw. The preliminary impressions were taken with irreversible hydrocolloid impression material, and the final impressions were taken with additive silicone material. The occlusion height and the centric relations were registered as the classical technique. After the successful trial denture appointment, the surface of the plaster master model was covered by isolation polish. After this procedure, the master model was covered by even wax layer with 5mm thickness. It was designed to be thinner in the area of the resection line. The designed cavity was filled in with silicone impression material and covered with the folio. The base plate with the arranged teeth was fixed to the model, packed in the cuvette and finished from heat-cured acrylic resin with low quantity of residual monomer. After the polymerization process, the silicone material was removed, and the obturators cap was fixed to the denture’s base plate with cold cured acrylic resin. The obturator and the complete denture of the mandible were adjusted and articulated in patient’s mouth in the final clinical stage. Results: The applied prosthetic method allowed successful defect hermetization and helped for the restoration of the speech, feeding and patient’s self-esteem. Conclusion: Prosthetic rehabilitation of patients with maxillary resection is possible only with the application of specific treatment methods.

Prosthetic joint infection due to Lysobacter thermophilus diagnosed by 16S rRNA gene sequencing

Directory of Open Access Journals (Sweden)

B Dhawan

2016-01-01

Full Text Available We report the first case of prosthetic joint infection caused by Lysobacter thermophilus which was identified by 16S rRNA gene sequencing. Removal of prosthesis followed by antibiotic treatment resulted in good clinical outcome. This case illustrates the use of molecular diagnostics to detect uncommon organisms in suspected prosthetic infections.

Prosthesis use in adult acquired major upper-limb amputees: patterns of wear, prosthetic skills and the actual use of prostheses in activities of daily life.

Science.gov (United States)

Østlie, Kristin; Lesjø, Ingrid Marie; Franklin, Rosemary Joy; Garfelt, Beate; Skjeldal, Ola Hunsbeth; Magnus, Per

2012-11-01

To describe patterns of prosthesis wear and perceived prosthetic usefulness in adult acquired upper-limb amputees (ULAs). To describe prosthetic skills in activities of daily life (ADL) and the actual use of prostheses in the performance of ADL tasks. To estimate the influence of prosthetic skills on actual prosthesis use and the influence of background factors on prosthetic skills and actual prosthesis use. Cross-sectional study analysing population-based questionnaire data (n = 224) and data from interviews and clinical testing in a referred/convenience sample of prosthesis-wearing ULAs (n = 50). Effects were analysed using linear regression. 80.8% wore prostheses. 90.3% reported their most worn prosthesis as useful. Prosthetic usefulness profiles varied with prosthetic type. Despite demonstrating good prosthetic skills, the amputees reported actual prosthesis use in only about half of the ADL tasks performed in everyday life. In unilateral amputees, increased actual use was associated with sufficient prosthetic training and with the use of myoelectric vs cosmetic prostheses, regardless of amputation level. Prosthetic skills did not affect actual prosthesis use. No background factors showed significant effect on prosthetic skills. Most major ULAs wear prostheses. Individualised prosthetic training and fitting of myoelectric rather than passive prostheses may increase actual prosthesis use in ADL.

Active drug users - struggling for rights and recognition in Denmark

DEFF Research Database (Denmark)

Anker, Jørgen

This paper examines the strategic dilemmas and the self-representation of the Drug Users’ Union in Denmark. The paper explores how a group of drug users on the one hand seeks to struggle for the rights of drug users and one the other hand seeks to gain legitimacy and access to public funding...... and support. It reveals how the organisation attempts to advance a more balanced image of drug users as persons who are able to run an effective organisation while they also claim the right to use drugs....

Hand hygiene in reducing transient flora on the hands of healthcare workers: an educational intervention.

Science.gov (United States)

Kapil, R; Bhavsar, H K; Madan, M

2015-01-01

Hand hygiene has now been recognised as one of the most effective intervention to control the transmission of infections in a hospital and education is an important tool to ensure its implementation. In order to convince the users and as a part of education, it is important to generate evidence on the role of hand hygiene in reducing the bacterial flora on their hands. The present study was undertaken in a tertiary care hospital to demonstrate the presence of bacterial flora on the hands of healthcare workers (HCW) in different categories, to teach them proper hand hygiene technique using alcohol-based hand rub and determine the outcome for reduction of bacteria. A total sample size of 60 subjects including resident doctors, medical students, nurses and hospital attendants were included in the study after obtaining informed consent. Each person was educated on the technique of hand hygiene with alcohol-based hand rub and hand impressions were cultured before and after hand hygiene. All the subjects were also given a questionnaire to assess their perception on hand hygiene. The WHO posters on proper hand hygiene were displayed in the appropriate areas of the hospital in addition, as an educational tool. Majority (42 out of 60) of the HCWs had bacterial count up to 100 colonies or more on both hands before the application of hand rub while working in the hospital. After use of alcohol hand rub with a proper hand hygiene technique, it was found that the percentage reduction was 95-99% among doctors and nurses, 70% among hospital attendants and 50% among sanitary attendants. Staphylococcus aureus was present on the hands of eight persons of which three were methicillin-resistant Staphylococcus aureus. The study demonstrates that transient bacteria are present on the hands of HCWs but majority could be removed by proper hand hygiene, which needs continuous education to be effective. It also shows that active education by demonstrating the proper hand hygiene technique

Significance of angular mismatch between vertebral endplate and prosthetic endplate in lumbar total disc replacement.

Science.gov (United States)

Lee, Chong Suh; Chung, Sung Soo; Oh, Sung Kyun; You, Je Wook

2011-05-01

A retrospective study. To determine whether angular mismatch between the vertebral endplate and prosthetic endplate during lumbar total disc replacement (L-TDR) affects the radiological and clinical outcomes. A prosthesis anchored to the vertebral body by using a large central keel carries an inherent risk of angular mismatch between the vertebral endplate and prosthetic endplate at a segment with a greater degree of lordosis, such as L5-S1. Theoretically, this angular mismatch can cause several problems, such as segmental hyperlordosis, anterior positioning of the upper prosthesis, posterior prosthetic edge subsidence, decreased range of motion (ROM), and a poor clinical outcome. This study evaluated 64 prosthetic levels of 56 patients who were implanted with L-TDR between June 2002 and February 2006. There were 38 and 26 prosthetic levels at the L4-5 and L5-S1, respectively. The mean follow-up period was 25.6 (12 to 49) months. The angle of mismatch between the lower endplate of the upper vertebral body and the upper prosthetic plate, segmental flexion/extension ROM, segmental lordosis angle at extension, distance from the posterior wall of the vertebral body to the posterior prosthetic edge were measured by obtaining radiographs. Clinically, the Visual Analogue Scale and Oswestry Disability Index were also evaluated. The angular mismatches between the upper vertebra and prosthesis at L4-5 and L5-S1 were 1.6 degree and 5.6 degree, respectively (P body to the posterior edge of the prosthesis in L5-S1 were 6.8 degree (4 to 13), 12.8 degree (8 to 17), and 3.8 mm (1 to 6 mm) in patients with an angular mismatch of 0.05). Angular mismatch was more common in L5-S1 than in L4-5. L-TDR at the most lordotic level, L5-S1, and implantation of an upper prosthesis with a mismatched angle seem to be the causes of a reduced segmental ROM, increased segmental lordosis, and anterior malpositioning of the prosthesis. However, these changes do not affect the clinical outcomes of

Differential contributions of specimen types, culturing, and 16S rRNA sequencing in diagnosis of prosthetic joint infections

DEFF Research Database (Denmark)

Larsen, Lone Heimann; Khalid, Vesal; Xu, Yijuan

2018-01-01

Prosthetic joint failure is mainly caused by infection, aseptic failure (AF), and mechanical problems. Infection detection has been improved with modified culture methods and molecular diagnostics. However, comparisons between modified and conventional microbiology methods are difficult due...... to variations in specimen sampling. In this prospective, multidisciplinary study of hip or knee prosthetic failures, we assessed the contributions of different specimen types, extended culture incubations, and 16S rRNA sequencing for diagnosing prosthetic joint infections (PJI). Project specimens included joint...... fluid (JF), bone biopsy specimens (BB), soft-tissue biopsy specimens (STB), and swabs (SW) from the prosthesis, collected in situ, and sonication fluid collected from prosthetic components (PC). Specimens were cultured for 6 (conventional) or 14 days, and 16S rRNA sequencing was performed at study...

Diagnostic evaluation of left-sided prosthetic heart valve dysfunction

NARCIS (Netherlands)

Habets, Jesse; Budde, Ricardo P.; Symersky, Petr; van den Brink, Renee B.; de Mol, Bas A.; Mali, Willem P.; van Herwerden, Lex A.; Chamuleau, Steven A.

Prosthetic heart valve (PHV) dysfunction is a rare, but potentially life-threatening, complication. In clinical practice, PHV dysfunction poses a diagnostic dilemma. Echocardiography and fluoroscopy are the imaging techniques of choice and are routinely used in daily practice. However, these

Diagnostic evaluation of left-sided prosthetic heart valve dysfunction

NARCIS (Netherlands)

Habets, Jesse; Budde, Ricardo P.; Symersky, Petr; van den Brink, Renee B.; de Mol, Bas A.; Mali, Willem P.; van Herwerden, Lex A.; Chamuleau, Steven A.

2011-01-01

Prosthetic heart valve (PHV) dysfunction is a rare, but potentially life-threatening, complication. In clinical practice, PHV dysfunction poses a diagnostic dilemma. Echocardiography and fluoroscopy are the imaging techniques of choice and are routinely used in daily practice. However, these

Prosthetic model, but not stiffness or height, affects the metabolic cost of running for athletes with unilateral transtibial amputations.

Science.gov (United States)

Beck, Owen N; Taboga, Paolo; Grabowski, Alena M

2017-07-01

Running-specific prostheses enable athletes with lower limb amputations to run by emulating the spring-like function of biological legs. Current prosthetic stiffness and height recommendations aim to mitigate kinematic asymmetries for athletes with unilateral transtibial amputations. However, it is unclear how different prosthetic configurations influence the biomechanics and metabolic cost of running. Consequently, we investigated how prosthetic model, stiffness, and height affect the biomechanics and metabolic cost of running. Ten athletes with unilateral transtibial amputations each performed 15 running trials at 2.5 or 3.0 m/s while we measured ground reaction forces and metabolic rates. Athletes ran using three different prosthetic models with five different stiffness category and height combinations per model. Use of an Ottobock 1E90 Sprinter prosthesis reduced metabolic cost by 4.3 and 3.4% compared with use of Freedom Innovations Catapult [fixed effect (β) = -0.177; P Run (β = -0.139; P = 0.002) prostheses, respectively. Neither prosthetic stiffness ( P ≥ 0.180) nor height ( P = 0.062) affected the metabolic cost of running. The metabolic cost of running was related to lower peak (β = 0.649; P = 0.001) and stance average (β = 0.772; P = 0.018) vertical ground reaction forces, prolonged ground contact times (β = -4.349; P = 0.012), and decreased leg stiffness (β = 0.071; P running. Instead, an optimal prosthetic model, which improves overall biomechanics, minimizes the metabolic cost of running for athletes with unilateral transtibial amputations. NEW & NOTEWORTHY The metabolic cost of running for athletes with unilateral transtibial amputations depends on prosthetic model and is associated with lower peak and stance average vertical ground reaction forces, longer contact times, and reduced leg stiffness. Metabolic cost is unrelated to prosthetic stiffness, height, and stride kinematic symmetry. Unlike nonamputees who decrease leg stiffness with

Distal anastomotic vein adjunct usage in infrainguinal prosthetic bypasses.

Science.gov (United States)

McPhee, James T; Goodney, Philip P; Schanzer, Andres; Shaykevich, Shimon; Belkin, Michael; Menard, Matthew T

2013-04-01

Single-segment saphenous vein remains the optimal conduit for infrainguinal revascularization. In its absence, prosthetic conduit may be used. Existing data regarding the significance of anastomotic distal vein adjunct (DVA) usage with prosthetic grafts are based on small series. This is a retrospective cohort analysis derived from the regional Vascular Study Group of New England as well as the Brigham and Women's hospital database. A total of 1018 infrainguinal prosthetic bypass grafts were captured in the dataset from 73 surgeons at 15 participating institutions. Propensity scoring and 3:1 matching was performed to create similar exposure groups for analysis. Outcome measures of interest included: primary patency, freedom from major adverse limb events (MALEs), and amputation free survival at 1 year as a function of vein patch utilization. Time to event data were compared with the log-rank test; multivariable Cox proportional hazard models were used to evaluate the adjusted association between vein cuff usage and the primary end points. DVA was defined as a vein patch, cuff, or boot in any configuration. Of the 1018 bypass operations, 94 (9.2%) had a DVA whereas 924 (90.8%) did not (no DVA). After propensity score matching, 88 DVAs (25%) and 264 no DVAs (75%) were analyzed. On univariate analysis of the matched cohort, the DVA and no DVA groups were similar in terms of mean age (70.0 vs 69.0; P = .55), male sex (58.0% vs 58.3%; P > .99), and preoperative characteristics such as living at home (93.2% vs 94.3%; P = .79) and independent ambulatory status (72.7% vs 75.7%; P = .64). The DVA and no DVA groups had similar rates of major comorbidities such as hypertension chronic obstructive pulmonary disease, diabetes mellitus, coronary artery disease, and dialysis dependence (P > .05 for all). Likewise, they had similar rates of distal origin grafts (13.6% vs 12.5%; P = .85), critical limb ischemia indications (P = .53), and prior arterial bypass (58% vs 47%; P = .08

Production of radioiodinated prosthetic group for indirect protein labeling

International Nuclear Information System (INIS)

Santos, Josefina da Silva

2001-01-01

Monoclonal antibodies and their fragments and, more recently, radiolabeled peptides have been extensively studied in order to develop radiopharmaceuticals for diagnostic and therapy in Nuclear Medicine. The radioiodination of proteins can be done by a direct method, with radioiodine being incorporated in to a tyrosine residue of the protein by electrophilic substitution. The main problem in the use of radioiodinated proteins, is that they are often dehalogenated in vivo by the action of specific enzymes, probably because of the structural similarity between iodophenyl groups and thyroid hormones. Several protein radioiodination methods have been developed in order to minimize this in vivo dehalogenation using prosthetic groups for indirect labeling. In this case, the radioiodine is first incorporated in to the prosthetic group that is subsequently attached to a terminal amino group or to a ε-amino group of lysine residue. The aim of this work is to obtain a radioiodinated prosthetic group for indirect labeling of proteins. The prosthetic group selected was the N-succinimidyl-4-radioiodine benzoate (SIB), obtained by the iodination of the p-bromobenzoic acid followed by the reaction with TSTU (0-(N-succinimidyl)-N,N,N',N'-tetramethyl uronium tetrafluoroborate) The results of these studies showed that the p-radio iodobenzoic acid was obtained with a radiochemical purity greater than 92% and a labeling yield of about 65%. Some reaction parameters were studied like temperature, time and Cu Cl mass (cataliser). The SIB was quantitatively obtained from p-radio iodobenzoic acid, using basic medium and after removing the water from the reaction using an nitrogen stream. The kinetic of this reaction is very fast with complete consumption of the p-radioiodebenzoic acid after 5 minutes. The coupling of the SIB prosthetic group to the protein was studied using Human Immunoglobulin (IgG) as a protein model. In a comparative way, the same protein was used on direct labeling

Development and testing of new upper-limb prosthetic devices: research designs for usability testing.

Science.gov (United States)

Resnik, Linda

2011-01-01

The purposes of this article are to describe usability testing and introduce designs and methods of usability testing research as it relates to upper-limb prosthetics. This article defines usability, describes usability research, discusses research approaches to and designs for usability testing, and highlights a variety of methodological considerations, including sampling, sample size requirements, and usability metrics. Usability testing is compared with other types of study designs used in prosthetic research.

Amputation rehabilitation and prosthetic restoration. From surgery to community reintegration.

Science.gov (United States)

Esquenazi, Alberto

The purpose of this review is to summarize the literature related to the advances that have taken place in the management and rehabilitation care of limb amputation. Prostheses for the lower and upper limb amputee have changed greatly over the past several years, with advances in components, socket fabrication and fitting techniques, suspension systems and sources of power and electronic controls. Higher levels of limb amputation can now be fitted with functional prostheses, which allow more patients to achieve independent life styles. This is of particular importance for the multi-limb amputee. The rehabilitation of more traditional lower limb levels of amputation have also greatly benefited from the technological advances including energy storing feet, electronic control hydraulic knees, ankle rotators and shock absorbers to mention a few. For the upper limb amputee, myoelectric and proportional controlled terminal devices and elbow joints are now used routinely in some rehabilitation facilities. Experimental prosthetic fitting techniques and devices such as the use of osseo-implantation for suspension of the prosthesis, tension control hands or electromagnetic fluids for knee movement control will also be briefly discussed in this paper. It is possible to conclude from this review that many advances have occurred that have greatly impacted the functional outcomes of patients with limb amputation.

Design, Sensing and Control of a Robotic Prosthetic Eye for Natural Eye Movement

OpenAIRE

J. J. Gu; M. Meng; A. Cook; P. X. Liu

2006-01-01

Loss of an eye is a tragedy for a person, who may suffer psychologically and physically. This paper is concerned with the design, sensing and control of a robotic prosthetic eye that moves horizontally in synchronization with the movement of the natural eye. Two generations of robotic prosthetic eye models have been developed. The first generation model uses an external infrared sensor array mounted on the frame of a pair of eyeglasses to detect the natural eye movement and to feed the contro...

Vibrotactile sensory substitution elicits feeling of ownership of an alien hand.

Directory of Open Access Journals (Sweden)

Marco D'Alonzo

Full Text Available Tactile feedback plays a key role in the attribution of a limb to the self and in the motor control of grasping and manipulation. However, due to technological limits, current prosthetic hands do not provide amputees with cutaneous touch feedback. Recent findings showed that amputees can be tricked into experiencing an alien rubber hand as part of their own body, by applying synchronous touches to the stump which is out of view, and to the rubber hand in full view. It was suggested that similar effects could be achieved by using a prosthesis with touch sensors that provides synchronous cutaneous feedback through an array of tactile stimulators on the stump. Such a prosthesis holds the potential to be easily incorporated within one's body scheme, because it would reproduce the perceptual illusion in everyday usage. We propose to use sensory substitution--specifically vibrotactile--to address this issue, as current haptic technology is still too bulky and inefficient. In this basic study we addressed the fundamental question of whether visuo-tactile modality mismatch promotes self-attribution of a limb, and to what extent compared to a modality-matched paradigm, on normally-limbed subjects. We manipulated visuo-tactile stimulations, comprising combinations of modality matched, modality mismatched, synchronous and asynchronous stimulations, in a set of experiments fashioned after the Rubber Hand Illusion. Modality mismatched stimulation was provided using a keypad-controlled vibrotactile display. Results from three independent measures of embodiment (questionnaires, pointing tests and skin conductance responses indicate that vibrotactile sensory substitution can be used to induce self-attribution of a rubber hand when synchronous but modality-conflicting visuo-tactile stimulation is delivered to the biological finger pads and to the equivalent rubber hand phalanges.

Roles and challenges of the multidisciplinary team involved in prosthetic rehabilitation, in a rural district in South Africa

Directory of Open Access Journals (Sweden)

Ennion L

2016-10-01

Full Text Available Liezel Ennion, Anthea Rhoda Department of Physiotherapy, Faculty of Community and Health Sciences, University of the Western Cape, Cape Town, South Africa Background: Major lower limb amputations result in a significant sense of loss, psychological stress, and decrease in function and overall quality of life for the amputee. The holistic, patient-centered prosthetic rehabilitation of an amputee requires input from a team of dedicated health professionals from different disciplines commonly referred to as a multidisciplinary team (MDT. MDT rehabilitation is considered crucial in the reintegration of the amputee into the community, as well as for providing psychological support after limb loss. Multidisciplinary and interdisciplinary rehabilitation has been proven to be more successful than therapy provided by individual therapists in a number of different populations, regardless of the population studied. However, in most developing countries, there is a significant lack of multidisciplinary rehabilitation.Aim: To explore the roles and challenges of the members of the MDT involved in trans-tibial amputation rehabilitation in a rural community in South Africa (SA.Design: An explorative sequential qualitative descriptive study.Setting: A rural district in the KwaZulu Natal province in SA.Participants: Nine prosthetic users, three surgeons, three traditional healers, 17 therapists, four prosthetists, and four community health workers.Instruments for data collection: Semistructured interviews and focus group discussions.Results: The roles of the members of the MDT were clarified, and various members of the MDT highlighted specific challenges relating to their experiences and roles in the rehabilitation team. Lack of interdisciplinary rehabilitation and communication among team members, as well as lack of resources, and patient education negatively impact the rehabilitation of trans-tibial amputees.Conclusion: Aiming to address the limited resources

Tensile strength and impact resistance properties of materials used in prosthetic check sockets, copolymer sockets, and definitive laminated sockets

OpenAIRE

Maria J. Gerschutz, PhD; Michael L. Haynes, MS; Derek M. Nixon, BS; James M. Colvin, MS

2011-01-01

Prosthetic sockets serve as the interface between people with amputations and their prostheses. Although most materials used to make prosthetic sockets have been used for many years, knowledge of these materials' properties is limited, especially after they are subjected to fabrication processes. This study evaluated tensile and impact properties of the current state-of-the-art materials used to fabricate prosthetic check sockets, copolymer sockets, and definitive laminated sockets. Thermolyn...

Telemedicine consulting in the patient preparation and planning of prosthetic tooth replacement.

Science.gov (United States)

Mladenović, Dragan; Tosić, Goran; Zivković, Dusan; Djindjić, Natasa; Mladenović, Lidija; Mladenović, Sanja; Marković, Ivana

2013-09-01

In the management of edentulous spaces, there is a permanent need of a dentist-prosthetician in charge to consult other specialists. Modern telemedicine, based on powerful computer and telecomunication systems, offers an adequate answer to these challenges, being able to transfer and obtain clinical data and consultation information over large distances. Using smartphone or a computer, the teleconsultant acces the system, downloads and review the data and photographs and gave suggestions. The system then enables direct, real time contact with the consultant, chat, or directs them to contact each other by phone. We presented telemedicine consulting in the patient preparation and planning of prosthetic tooth replacement in 3 cases with different teleconsultation requirements: the first case for prosthetic rehabilitation of his upper teeth, the second one for prosthetic management of his partial edentulousness and "a growth on his gums" in the vestibular region of the frontal teeth and the third one for prosthetic management of total edentulousness of her upper jaw. We used the system of telemedicine in dentistry, established at the Faculty of Medicine in Kosovska Mitrovica. The operation was based on the computer application system XPA3 Online, computer networking and mobile smartphone network. All consultations were succefull with no need for further procedures in regional center. The use of a mobile smartphone has brought about the mobility and availability of teleconsultant specialists in an extent never seen before. Prostheticians are thus able to offer better service to their patients and improve the quality of management of partially or totally edentulous patients, especially in rural areas.

Peri-prosthetic fractures around tumor endoprostheses: a retrospective analysis of eighteen cases.

Science.gov (United States)

Barut, Nicolas; Anract, Philippe; Babinet, Antoine; Biau, David

2015-09-01

Tumour hip and knee endoprostheses have become the mainstay for reconstruction of patients with bone tumours. Fixation into host bone has improved over time. However, some patients present with a peri-prosthetic fracture over follow-up. The objective of this study was to analyse the mode of presentation and survival of implant after a peri-prosthetic fracture around a tumour endoprosthesis. Eighteen peri-prosthetic fractures (17 patients) were included. All patients were treated at a tertiary care center. There were 11 (65%) women; the median age at the time of fracture was 38 years old. All implants were cemented and all knee endoprostheses were fixed-hinge. Twelve (67%) fractures occurred after femoral resection and six (33%) fractures after proximal tibial resection. There were three femoral neck fractures (UCS C), three femoral shaft type C fractures, two femoral shaft type B1, one tibial shaft type B2, three tibial shaft type C, three ankle fractures (UCS C) and three patella fractures (UCS F). Two fractures were treated conservatively and 16 were operated on. Only one patient had the implant revised. There were eight (44%) failures over follow-up; none of the conservative treatment failed. The cumulative probability of failure for any reason was 27% (8-52) and 55% (22-79) at five and ten years, respectively. Peri-prosthetic fractures around massive endoprostheses are different from that of standard implants. There are more type C fractures; internal fixation is an attractive option at the time of presentation but the risk of revision over follow-up is high and patients should be informed accordingly.

Creative prosthetic foot selection enables successful ambulation in stiletto high heels.

Science.gov (United States)

Russell Esposito, Elizabeth; Lipe, Delbert H; Rábago, Christopher A

2017-11-01

Walking in high heels presents biomechanical challenges, yet they remain part of many women's attire. However, women with a lower limb amputation are limited in available footwear options. Case description and methods: This case study is in response to one patient's assertion that she walked better and more symmetrically in heels than flat shoes with her below-knee prosthesis. She underwent gait analysis in athletic shoes and 10-cm stiletto high heels worn with a pediatric running foot to determine if these claims could be substantiated through biomechanical measures. Global gait asymmetry indices were calculated. Findings and outcomes: Asymmetry indices were nearly identical between athletic shoes and heels but joint-level findings differed substantially. Ankle mechanics were more symmetrical in heels but hip mechanics were less. The maintenance of symmetry in stiletto high heels does not imply maintenance of gait quality, as high heels are known to adversely affect some components walking mechanics. Clinical relevance Returning to high-heel wear is achievable for prosthesis users. Accommodations can be made using creativity in prosthetic foot selection to enable successful ambulation; however, attention to gait mechanics may be important for patient safety.

Comparative study of radiography and scintigraphy for loosening and infection of prosthetic hip replacement

Energy Technology Data Exchange (ETDEWEB)

Park, Mi Sook; Lee, Sun Wha; Choi, Woo Suk; Lim, Joo Won; Song, Han Joon; Ahn, Chi Yul [College of Medicine, Kyung Hee University, Seoul (Korea, Republic of)

1987-10-15

Prosthetic hip replacement is associated with certain complications which result in a painful hip. Many of these, e. g. prosthetic dislocation, fracture, trochanteric avulsion, and heterotopic calcification are easily diagnosed by conventional radiography. However, radiographic evaluation for infection and/pr loosening of prosthesis as major complications requiring reoperation often contributes little to the resolution of the diagnostic problem. The authors made a comparative study of plain radiography and scintigraphy of 39 cases performed revision at Kyung Hee University Hospital from Sep. '81-to Aug. '86. The results were as follows: 1. In 39 revised prosthetic hip replacement, 26 cases (67%) of loosening without infection and 11 cases (28%) of infection were proven. 2. In loosening of prosthesis, plain radiography showed true positive rate of 76% and true negative rate of 60%, and scintigraphy showed true positive rate of 75% and true negative rate of 95%. 3. In infection of prosthesis, plain radiography revealed true positive rate of 55% and true negative rate of 96%, and scintigraphy revealed true positive rate of 100% and true negative rate of 83%. 4. Scintigraphy and plain radiography were useful as complementary procedure in evaluating and differentiating loosening and/or infection of prosthetic component.

Customized mold radiotherapy with prosthetic apparatus for oral cancers

International Nuclear Information System (INIS)

Noguchi, Tadahide; Tsuchiya, Yoshiyuki; Hayasaka, Junichi; Itoh, Hiroto; Jinbu, Yoshinori; Kusama, Mikio; Takahashi, Satoru; Nakazawa, Masanori

2014-01-01

Eight patients (6 males, 2 females; median age, 78 years; age range, 31-94 years) were treated by mold radiotherapy with a prosthetic apparatus for oral cancers between October 2006 and March 2013. The primary sites were the tongue in 3 cases, hard palate and buccal mucosa in 2 cases each, and oral floor in 1 case. The type of treatment consisted of radical radiotherapy and palliative radiotherapy in 2 cases each, and preoperative radiotherapy, postoperative radiotherapy, additional radiotherapy after external beam radiotherapy and systemic chemotherapy in 1 case each. Patients received 40-50 Gy in 8-10 fractions with mold radiotherapy. Two patients who received radical radiotherapy showed no signs of recurrence or metastasis. The present therapy contributed to patients' palliative, postoperative, and preoperative therapy. Mold radiotherapy with a prosthetic appliance was performed safely and was a useful treatment for several types of oral cancer. (author)

Neuro-prosthetic interplay. Comment on "Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands" by M. Santello et al.

Science.gov (United States)

Schieber, Marc H.

2016-07-01

Control of the human hand has been both difficult to understand scientifically and difficult to emulate technologically. The article by Santello and colleagues in the current issue of Physics of Life Reviews[1] highlights the accelerating pace of interaction between the neuroscience of controlling body movement and the engineering of robotic hands that can be used either autonomously or as part of a motor neuroprosthesis, an artificial body part that moves under control from a human subject's own nervous system. Motor neuroprostheses typically involve a brain-computer interface (BCI) that takes signals from the subject's nervous system or muscles, interprets those signals through a decoding algorithm, and then applies the resulting output to control the artificial device.

Real-Time Control of an Exoskeleton Hand Robot with Myoelectric Pattern Recognition.

Science.gov (United States)

Lu, Zhiyuan; Chen, Xiang; Zhang, Xu; Tong, Kay-Yu; Zhou, Ping

2017-08-01

Robot-assisted training provides an effective approach to neurological injury rehabilitation. To meet the challenge of hand rehabilitation after neurological injuries, this study presents an advanced myoelectric pattern recognition scheme for real-time intention-driven control of a hand exoskeleton. The developed scheme detects and recognizes user's intention of six different hand motions using four channels of surface electromyography (EMG) signals acquired from the forearm and hand muscles, and then drives the exoskeleton to assist the user accomplish the intended motion. The system was tested with eight neurologically intact subjects and two individuals with spinal cord injury (SCI). The overall control accuracy was [Formula: see text] for the neurologically intact subjects and [Formula: see text] for the SCI subjects. The total lag of the system was approximately 250[Formula: see text]ms including data acquisition, transmission and processing. One SCI subject also participated in training sessions in his second and third visits. Both the control accuracy and efficiency tended to improve. These results show great potential for applying the advanced myoelectric pattern recognition control of the wearable robotic hand system toward improving hand function after neurological injuries.

Red flag in the emergency department: fracture and primary failure of a prosthetic valve.

Science.gov (United States)

Ozsarac, Murat; Karcioglu, Ozgur; Ayrik, Cuneyt; Bozkurt, Seyran; Turkcuer, Ibrahim; Gumrukcu, Serhat

2005-07-01

This case report concerns a patient with fracture and primary dysfunction of a prosthetic valve. A 40-year-old man presented to the Emergency Department with a chief complaint of breakthrough pleuritic back pain and shortness of breath. Past surgical history was significant only for an aortic valve replacement and mitral valve replacement performed 16 years prior. The transthoracic echocardiography raised suspicion of prosthesis malposition. The patient was taken to the operating room by cardiothoracic surgeons for valve replacement. Operative findings revealed that a prosthetic valve leaflet in the mitral position had broken off. Primary prosthetic valve failure should not be overlooked in the differential diagnosis of patients with valve replacement and a rapidly deteriorating clinical course. Emergency echocardiography is a guide to convenient diagnosis and management. Early surgical consultation and early reparative surgery might prevent unnecessary morbidity and mortality.

Developing and modeling of voice control system for prosthetic robot arm in medical systems

Directory of Open Access Journals (Sweden)

Koksal Gundogdu

2018-04-01

Full Text Available In parallel with the development of technology, various control methods are also developed. Voice control system is one of these control methods. In this study, an effective modelling upon mathematical models used in the literature is performed, and a voice control system is developed in order to control prosthetic robot arms. The developed control system has been applied on four-jointed RRRR robot arm. Implementation tests were performed on the designed system. As a result of the tests; it has been observed that the technique utilized in our system achieves about 11% more efficient voice recognition than currently used techniques in the literature. With the improved mathematical modelling, it has been shown that voice commands could be effectively used for controlling the prosthetic robot arm. Keywords: Voice recognition model, Voice control, Prosthetic robot arm, Robotic control, Forward kinematic

Dynamic Facial Prosthetics for Sufferers of Facial Paralysis

Directory of Open Access Journals (Sweden)

Fergal Coulter

2011-10-01

Full Text Available BackgroundThis paper discusses the various methods and the materialsfor the fabrication of active artificial facial muscles. Theprimary use for these will be the reanimation of paralysedor atrophied muscles in sufferers of non-recoverableunilateral facial paralysis.MethodThe prosthetic solution described in this paper is based onsensing muscle motion of the contralateral healthy musclesand replicating that motion across a patient’s paralysed sideof the face, via solid state and thin film actuators. Thedevelopment of this facial prosthetic device focused onrecreating a varying intensity smile, with emphasis ontiming, displacement and the appearance of the wrinklesand folds that commonly appear around the nose and eyesduring the expression.An animatronic face was constructed with actuations beingmade to a silicone representation musculature, usingmultiple shape-memory alloy cascades. Alongside theartificial muscle physical prototype, a facial expressionrecognition software system was constructed. This formsthe basis of an automated calibration and reconfigurationsystem for the artificial muscles following implantation, soas to suit the implantee’s unique physiognomy.ResultsAn animatronic model face with silicone musculature wasdesigned and built to evaluate the performance of ShapeMemory Alloy artificial muscles, their power controlcircuitry and software control systems. A dual facial motionsensing system was designed to allow real time control overmodel – a piezoresistive flex sensor to measure physicalmotion, and a computer vision system to evaluate real toartificial muscle performance.Analysis of various facial expressions in real subjects wasmade, which give useful data upon which to base thesystems parameter limits.ConclusionThe system performed well, and the various strengths andshortcomings of the materials and methods are reviewedand considered for the next research phase, when newpolymer based artificial muscles are constructed

Ureaplasma parvum prosthetic joint infection detected by PCR.

Science.gov (United States)

Farrell, John J; Larson, Joshua A; Akeson, Jeffrey W; Lowery, Kristin S; Rounds, Megan A; Sampath, Rangarajan; Bonomo, Robert A; Patel, Robin

2014-06-01

We describe the first reported case of Ureaplasma parvum prosthetic joint infection (PJI) detected by PCR. Ureaplasma species do not possess a cell wall and are usually associated with colonization and infection of mucosal surfaces (not prosthetic material). U. parvum is a relatively new species name for certain serovars of Ureaplasma urealyticum, and PCR is useful for species determination. Our patient presented with late infection of his right total knee arthroplasty. Intraoperative fluid and tissue cultures and pre- and postoperative synovial fluid cultures were all negative. To discern the pathogen, we employed PCR coupled with electrospray ionization mass spectrometry (PCR/ESI-MS). Our patient's failure to respond to empirical antimicrobial treatment and our previous experience with PCR/ESI-MS in culture-negative cases of infection prompted us to use this approach over other diagnostic modalities. PCR/ESI-MS detected U. parvum in all samples. U. parvum-specific PCR testing was performed on all synovial fluid samples to confirm the U. parvum detection. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

A Prosthetic Foot Emulator to Optimize Prescription of Prosthetic Feet in Veterans and Service Members with Leg Amputations

Science.gov (United States)

2017-09-01

mobility, prosthetic foot preference and walking ability after two weeks of use in the home and community setting. No exclusions based on sex , race...2012 Page 17 of 33 Data collection Photos and video recording With the participant’s explicit consent, we may take video and photos during portions of...this study, for documentation and use in research publications. All videos and photos will exclue the participant’s face and identifying marks will

Three-dimensional flow structures past a bio-prosthetic valve in an in-vitro model of the aortic root

OpenAIRE

Hasler, David; Obrist, Dominik

2018-01-01

The flow field past a prosthetic aortic valve comprises many details that indicate whether the prosthesis is functioning well or not. It is, however, not yet fully understood how an optimal flow scenario would look, i.e. which subtleties of the fluid dynamics in place are essential regarding the durability and compatibility of a prosthetic valve. In this study, we measured and analyzed the 3D flow field in the vicinity of a bio-prosthetic heart valve in function of the aortic root size. The m...

Current standard rules of combined anteversion prevent prosthetic impingement but ignore osseous contact in total hip arthroplasty.

Science.gov (United States)

Weber, Markus; Woerner, Michael; Craiovan, Benjamin; Voellner, Florian; Worlicek, Michael; Springorum, Hans-Robert; Grifka, Joachim; Renkawitz, Tobias

2016-12-01

In this prospective study of 135 patients undergoing cementless total hip arthroplasty (THA) we asked whether six current definitions of combined anteversion prevent impingement and increase postoperative patient individual impingement-free range-of-motion (ROM). Implant position was measured by an independent, external institute on 3D-CT performed six weeks post-operatively. Post-operative ROM was calculated using a CT-based algorithm detecting osseous and/or prosthetic impingement by virtual hip movement. Additionally, clinical ROM was evaluated pre-operatively and one-year post-operatively by a blinded observer. Combined component position of cup and stem according to the definitions of Ranawat, Widmer, Dorr, Hisatome and Yoshimine inhibited prosthetic impingement in over 90 %, while combined osseous and prosthetic impingement still occurred in over 40 % of the cases. The recommendations by Jolles, Widmer, Dorr, Yoshimine and Hisatome enabled higher flexion (p ≤ 0.001) and internal rotation (p ≤ 0.006). Clinically, anteversion rules of Widmer and Yoshimine provided one-year post-operatively statistically but not clinically relevant higher internal rotation (p ≤0.034). Standard rules of combined anteversion detect prosthetic but fail to prevent combined osseous and prosthetic impingement in THA. Future models will have to account for the patient-individual anatomic situation to ensure impingement-free ROM.

Oral health-related quality of life and prosthetic status of nursing home residents with or without dementia.

Science.gov (United States)

Klotz, Anna-Luisa; Hassel, Alexander Jochen; Schröder, Johannes; Rammelsberg, Peter; Zenthöfer, Andreas

2017-01-01

The objective of this cross-sectional study was to evaluate the effect of prosthetic status on the oral health-related quality of life (OHRQoL) of nursing home residents with or without dementia. The study was performed in 14 nursing homes across the federal state of Baden-Württemberg, Germany. All eligible participants were included, and general and medical information and information about their dental and prosthetic statuses were collected. The Geriatric Oral Health Assessment Index (GOHAI) was administered to evaluate OHRQoL. The Mini-Mental State Examination (MMSE) served to classify participants into living or not living with dementia according to the established cutoff value for dementia (MMSE health was also similar in both groups ( P >0.05). The number of teeth (odds ratio [OR]: 2.0), the type of prosthetic status (OR: 6.5), and denture-related treatment needs (OR: 2.4) were the major factors significantly affecting OHRQoL ( P nursing home residents is substantially compromised. Several prosthetic treatment needs for residents living with or without dementia were identified. Edentulism without tooth replacement and having <5 teeth resulted in an increased risk of substantially compromised OHRQoL. Further studies should be conducted to determine whether improvements in prosthetic status can increase OHRQoL.

Integration Head Mounted Display Device and Hand Motion Gesture Device for Virtual Reality Laboratory

Science.gov (United States)

Rengganis, Y. A.; Safrodin, M.; Sukaridhoto, S.

2018-01-01

Virtual Reality Laboratory (VR Lab) is an innovation for conventional learning media which show us whole learning process in laboratory. There are many tools and materials are needed by user for doing practical in it, so user could feel new learning atmosphere by using this innovation. Nowadays, technologies more sophisticated than before. So it would carry in education and it will be more effective, efficient. The Supported technologies are needed us for making VR Lab such as head mounted display device and hand motion gesture device. The integration among them will be used us for making this research. Head mounted display device for viewing 3D environment of virtual reality laboratory. Hand motion gesture device for catching user real hand and it will be visualized in virtual reality laboratory. Virtual Reality will show us, if using the newest technologies in learning process it could make more interesting and easy to understand.

An electromechanical swing-phase-controlled prosthetic knee joint for conversion of physiological energy to electrical energy: feasibility study.

Science.gov (United States)

Andrysek, Jan; Chau, Gilbert

2007-12-01

Microprocessor-controlled prostheses facilitate a more natural and efficient gait for individuals with above-knee amputations by continually adjusting the level of swing-phase damping. One caveat associated with these technologies is that the user must charge the onboard batteries on a daily basis. It is, therefore, the aim of this study to examine the feasibility of using an electromechanical system to provide prosthetic swing-phase damping and, concomitantly, the function of converting physiological energy that is normally dissipated during the swing phase, to electrical energy. Gait data from a single subject and data from a kinematic simulator were used to develop an empirical model. The findings in this study indicate that an electromagnetic system has appropriate characteristics for use in swing-phase control and also has the potential to recover energy under particular conditions.

Electromyography (EMG) signal recognition using combined discrete wavelet transform based adaptive neuro-fuzzy inference systems (ANFIS)

Science.gov (United States)

Arozi, Moh; Putri, Farika T.; Ariyanto, Mochammad; Khusnul Ari, M.; Munadi, Setiawan, Joga D.

2017-01-01

People with disabilities are increasing from year to year either due to congenital factors, sickness, accident factors and war. One form of disability is the case of interruptions of hand function. The condition requires and encourages the search for solutions in the form of creating an artificial hand with the ability as a human hand. The development of science in the field of neuroscience currently allows the use of electromyography (EMG) to control the motion of artificial prosthetic hand into the necessary use of EMG as an input signal to control artificial prosthetic hand. This study is the beginning of a significant research planned in the development of artificial prosthetic hand with EMG signal input. This initial research focused on the study of EMG signal recognition. Preliminary results show that the EMG signal recognition using combined discrete wavelet transform and Adaptive Neuro-Fuzzy Inference System (ANFIS) produces accuracy 98.3 % for training and 98.51% for testing. Thus the results can be used as an input signal for Simulink block diagram of a prosthetic hand that will be developed on next study. The research will proceed with the construction of artificial prosthetic hand along with Simulink program controlling and integrating everything into one system.

Designing distributed user interfaces for ambient intelligent environments using models and simulations

OpenAIRE

LUYTEN, Kris; VAN DEN BERGH, Jan; VANDERVELPEN, Chris; CONINX, Karin

2006-01-01