Prosthetic Engineering

MedlinePlus

... torque adapter in the pylons of transtibial amputees. Energy Storage & Release Many ambulatory lower limb amputees exhibit ... Future Directions Current Project Summaries Development of Controlled Energy Storage and Release Prosthetic Foot Development of Inverting- ...

Bariatric amputee: A growing problem?

PubMed

Kulkarni, Jai; Hannett, Dominic P; Purcell, Steven

2015-06-01

This study reviewed prevalence of patients with lower limb amputations with above normal weight profile, with body mass index over 25, in seven disablement services centres managing their amputee rehabilitation in the United Kingdom. To review two clinical standards of practice in amputee rehabilitation. Ambulant lower limb amputees should have their body weight recorded on an electronic information system, with identification of cohort with body weight >100 kg. Lower limb amputees to be provided with suitable weight-rated prosthesis. Observational study of clinical practice. Data were collected from the Clinical Information Management Systems. Inclusion criteria--subjects were ambulant prosthetic users with some prosthetic intervention in the last 5 years and had at least one lower limb amputation. In 96% of patients, the weight record profile was maintained. In addition, 86% were under 100 kg, which is the most common weight limit of prosthetic componentry. Of 15,204 amputation levels, there were 1830 transfemoral and transtibial sites in users with body weight over 100 kg. In 60 cases, the prosthetic limb build was rated to be below the user body weight. In 96% of our patients, body weight was documented, and in 97%, the prosthetic limb builds were within stated body weight limits, but this may not be the case in all the other disablement services centres in the United Kingdom. Also, the incidence of obesity in the United Kingdom is a growing problem, and the health issues associated with obesity are further compounded in the amputee population. Prosthetic componentry has distinct weight limits which must be considered during prescription. As people with amputation approach the limits of specific components, clinicians are faced with the challenge of continued provision in a safe and suitable manner. This article reviews the amputee population and the current national profile to consider trends in provision and the incidence of these challenges. © The International Society for Prosthetics and Orthotics 2014.

Prosthetic leg powered by MR brake and SMA wires

NASA Astrophysics Data System (ADS)

Nguyen, The; Munguia, Vicente; Calderon, Jose

2014-04-01

Current knee designs for prosthetic legs rely on electric motors for both moving and stationary states. The electric motors draw an especially high level of current to sustain a fixed position. The advantage of using magnetorheological (MR) fluid is that it requires less current and can have a variable braking torque. Besides, the proposed prosthetic leg is actuated by NiTinol wire, a popular shape memory alloy (SMA). The incorporation of NiTinol gives the leg more realistic weight distribution with appropriate arrangement of the batteries and wires. The prosthesis in this research was designed with MR brake as stopping component and SMA wire network as actuating component at the knee. The MR brake was designed with novel non-circular shape for the rotor that improved the braking torque while minimizing the power consumption. The design also helped simplify the control of braking process. The SMA wire network was design so that the knee motion was actively rotated in both directions. The SMA wires were arranged and played very similar role as the leg's muscles. The study started with the overall solid design of the knee including both MR and SMA parts. Theoretical models were derived and programmed in Simulink for both components. The simulation was capable of predicting the power required for moving the leg or hold it in a fixed position for a certain amount of time. Subsequently, the design was prototyped and tested to validate the theoretical prediction. The theoretical models were updated accordingly to correlate with the experimental data.

An extremely lightweight fingernail worn prosthetic interface device

NASA Astrophysics Data System (ADS)

Yetkin, Oguz; Ahluwalia, Simranjit; Silva, Dinithi; Kasi-Okonye, Isioma; Volker, Rachael; Baptist, Joshua R.; Popa, Dan O.

2016-05-01

Upper limb prosthetics are currently operated using several electromyography sensors mounted on an amputee's residual limb. In order for any prosthetic driving interface to be widely adopted, it needs to be responsive, lightweight, and out of the way when not being used. In this paper we discuss the possibility of replacing such electrodes with fingernail optical sensor systems mounted on the sound limb. We present a prototype device that can detect pinch gestures and communicate with the prosthetic system. The device detects the relative position of fingers to each other by measuring light transmitted via tissue. Applications are not limited to prosthetic control, but can be extended to other human-machine interfaces.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

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 undermore » 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.« less

Predictors of Success on the Prosthetics Certification Examination

ERIC Educational Resources Information Center

Miro, Rebecca Maria

2014-01-01

Students who graduate from a practitioner program in prosthetics & orthotics must achieve certification in order to obtain licensure and practice independently in 16 states. In states where licensure is not mandatory, graduates may choose to pursue certification in order assure patients that they are practicing at the highest level as well as…

First-in-Man Demonstration of Fully Implanted Myoelectric Sensors for Control of an Advanced Electromechanical Arm by Transradial Amputees

PubMed Central

Pasquina, Paul F.; Evangelista, Melissa; Carvalho, Antonio J.; Lockhart, Joseph; Griffin, Sarah; Nanos, George; McKay, Patricia; Hansen, Morten; Ipsen, Derek; Vandersea, James; Butkus, Josef; Miller, Matthew; Murphy, Ian; Hankin, David

2014-01-01

Background Advanced motorized prosthetic devices are currently controlled by EMG signals generated by residual muscles and recorded by surface electrodes on the skin. These surface recordings are often inconsistent and unreliable, leading to high prosthetic abandonment rates for individuals with upper limb amputation. Surface electrodes are limited because of poor skin contact, socket rotation, residual limb sweating, and their ability to only record signals from superficial muscles, whose function frequently does not relate to the intended prosthetic function. More sophisticated prosthetic devices require a stable and reliable interface between the user and robotic hand to improve upper limb prosthetic function. New Method Implantable Myoelectric Sensors (IMES®) are small electrodes intended to detect and wirelessly transmit EMG signals to an electromechanical prosthetic hand via an electromagnetic coil built into the prosthetic socket. This system is designed to simultaneously capture EMG signals from multiple residual limb muscles, allowing the natural control of multiple degrees of freedom simultaneously. Results We report the status of the first FDA-approved clinical trial of the IMES® System. This study is currently in progress, limiting reporting to only preliminary results. Comparison with Existing Methods Our first subject has reported the ability to accomplish a greater variety and complexity of tasks in his everyday life compared to what could be achieved with his previous myoelectric prosthesis. Conclusion The interim results of this study indicate the feasibility of utilizing IMES® technology to reliably sense and wirelessly transmit EMG signals from residual muscles to intuitively control a three degree-of-freedom prosthetic arm. PMID:25102286

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

NASA Astrophysics Data System (ADS)

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.

Periprosthetic Joint Infections: Clinical and Bench Research

PubMed Central

Legout, Laurence; Senneville, Eric

2013-01-01

Prosthetic joint infection is a devastating complication with high morbidity and substantial cost. The incidence is low but probably underestimated. Despite a significant basic and clinical research in this field, many questions concerning the definition of prosthetic infection as well the diagnosis and the management of these infections remained unanswered. We review the current literature about the new diagnostic methods, the management and the prevention of prosthetic joint infections. PMID:24288493

Smart Sensing and Dynamic Fitting for Enhanced Comfort and Performance of Prosthetics

DTIC Science & Technology

2017-10-01

studying microstrip resonators for bio- impedance measurement. For actuation, we have 1) improved and de -bugged the prosthetic interface control ...studying microstrip resonators for bio‐impedance measurement. For actuation, we have 1) improved and de -bugged the prosthetic interface control ...shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number

Current standard rules of combined anteversion prevent prosthetic impingement but ignore osseous contact in total hip arthroplasty.

PubMed

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.

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

PubMed

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.

77 FR 65609 - Advisory Committee on Prosthetics and Special-Disabilities Programs; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-29

... the Secretary of Veterans Affairs on VA's prosthetics programs designed to provide state-of-the- art... program administered by the Secretary to serve Veterans with spinal cord injuries, blindness or visual...

78 FR 69176 - Advisory Committee on Prosthetics and Special-Disabilities Programs; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-18

... the Secretary of Veterans Affairs on VA's prosthetics programs designed to provide state-of-the- art... program administered by the Secretary to serve Veterans with spinal cord injuries, blindness or visual...

75 FR 24775 - Advisory Committee on Prosthetics and Special Disabilities Programs; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-05

... state-of-the- art prosthetics and the associated rehabilitation research, development, and evaluation of..., blindness or visual impairment, loss of extremities or loss of function, deafness or hearing impairment, and...

76 FR 21107 - Advisory Committee on Prosthetics and Special-Disabilities Programs; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-14

... the Secretary of Veterans Affairs on VA's prosthetics programs designed to provide state-of-the art... program administered by the Secretary to serve Veterans with spinal cord injuries, blindness or visual...

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

PubMed

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.

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

PubMed Central

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

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

NASA Technical Reports Server (NTRS)

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

Optimal design of a magnetorheological damper used in smart prosthetic knees

NASA Astrophysics Data System (ADS)

Gao, Fei; Liu, Yan-Nan; Liao, Wei-Hsin

2017-03-01

In this paper, a magnetorheological (MR) damper is optimally designed for use in smart prosthetic knees. The objective of optimization is to minimize the total energy consumption during one gait cycle and weight of the MR damper. Firstly, a smart prosthetic knee employing a DC motor, MR damper and springs is developed based on the kinetics characteristics of human knee during walking. Then the function of the MR damper is analyzed. In the initial stance phase and swing phase, the MR damper is powered off (off-state). While during the late stance phase, the MR damper is powered on to work as a clutch (on-state). Based on the MR damper model as well as the prosthetic knee model, the instantaneous energy consumption of the MR damper is derived in the two working states. Then by integrating in one gait cycle, the total energy consumption is obtained. Particle swarm optimization algorithm is used to optimize the geometric dimensions of MR damper. Finally, a prototype of the optimized MR damper is fabricated and tested with comparison to simulation.

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

PubMed

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.

The role of vision processing in prosthetic vision.

PubMed

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.

Cobotic architecture for prosthetics.

PubMed

Faulring, Eeic L; Colgate, J Edward; Peshkin, Michael A

2006-01-01

We envision cobotic infinitely-variable transmissions (IVTs) as an enabling technology for haptics and prosthetics that will allow for increases in the dynamic range of these devices while simultaneously permitting reductions in actuator size and power requirements. Use of cobotic IVTs eliminates the need to make compromises on output flow and effort, which are inherent to choosing a fixed transmission ratio drivetrain. The result is a mechanism with enhanced dynamic range that extends continuously from a completely clutched state to a highly backdrivable state. This high dynamic range allows cobotic devices to control impedance with a high level of fidelity. In this paper, we discuss these and other motivations for using parallel cobotic transmission architecture in prosthetic devices.

Update on Bioactive Prosthetic Material for the Treatment of Hernias.

PubMed

Edelman, David S; Hodde, Jason P

2011-12-01

The use of mesh in the repair of hernias is commonplace. Synthetic mesh, like polypropylene, has been the workhorse for hernia repairs since the 1980s. Surgisis® mesh (Cook Surgical, Bloomington, IN), a biologic hernia graft material composed of purified porcine small intestinal submucosa (SIS), was first introduced to the United States in 1998 as an alternative to synthetic mesh materials. This mesh, composed of extracellular matrix collagen, fibronectin and associated glycosaminoglycans and growth factors, has been extensively investigated in animal models and used clinically in many types of surgical procedures. SIS acts as a scaffold for natural growth and strength. We reported our initial results in this publication in July 2006. Since then, there have been many more reports and numerous other bioactive prosthetic materials (BPMs) released. The object of this article is to briefly review some of the current literature on the use of BPM for inguinal hernias, sports hernias, and umbilical hernias.

Isolated Lactobacillus chronic prosthetic knee infection.

PubMed

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.

Prosthetic design directives: Low-cost hands within reach.

PubMed

Jones, G K; Rosendo, A; Stopforth, R

2017-07-01

Although three million people around the world suffer from the lack of one or both upper limbs 80% of this number is located within developing countries. While prosthetic prices soar with technology 3D printing and low cost electronics present a sensible solution for those that cannot afford expensive prosthetics. The electronic and control design of a low-cost prosthetic hand, the Touch Hand II, is discussed. This paper shows that sensorless techniques can be used to reduce design complexities, costs, and provide easier access to the electronics. A closing and opening finite state machine (COFSM) was developed to handle the actuated digit joint control state and a supervisory switching control scheme, used for speed and grip strength control. Three torque and speed settings were created to be preset for specific grasps. The hand was able to replicate ten frequently used grasps and grip some common objects. Future work is necessary to enable a user to control it with myoelectric signals (MESs) and to solve operational problems related to electromagnetic interference (EMI).

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

PubMed

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.

Literature Review on Needs of Upper Limb Prosthesis Users.

PubMed

Cordella, Francesca; Ciancio, Anna Lisa; Sacchetti, Rinaldo; Davalli, Angelo; Cutti, Andrea Giovanni; Guglielmelli, Eugenio; Zollo, Loredana

2016-01-01

The loss of one hand can significantly affect the level of autonomy and the capability of performing daily living, working and social activities. The current prosthetic solutions contribute in a poor way to overcome these problems due to limitations in the interfaces adopted for controlling the prosthesis and to the lack of force or tactile feedback, thus limiting hand grasp capabilities. This paper presents a literature review on needs analysis of upper limb prosthesis users, and points out the main critical aspects of the current prosthetic solutions, in terms of users satisfaction and activities of daily living they would like to perform with the prosthetic device. The ultimate goal is to provide design inputs in the prosthetic field and, contemporary, increase user satisfaction rates and reduce device abandonment. A list of requirements for upper limb prostheses is proposed, grounded on the performed analysis on user needs. It wants to (i) provide guidelines for improving the level of acceptability and usefulness of the prosthesis, by accounting for hand functional and technical aspects; (ii) propose a control architecture of PNS-based prosthetic systems able to satisfy the analyzed user wishes; (iii) provide hints for improving the quality of the methods (e.g., questionnaires) adopted for understanding the user satisfaction with their prostheses.

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

PubMed

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.

Literature Review on Needs of Upper Limb Prosthesis Users

PubMed Central

Cordella, Francesca; Ciancio, Anna Lisa; Sacchetti, Rinaldo; Davalli, Angelo; Cutti, Andrea Giovanni; Guglielmelli, Eugenio; Zollo, Loredana

2016-01-01

The loss of one hand can significantly affect the level of autonomy and the capability of performing daily living, working and social activities. The current prosthetic solutions contribute in a poor way to overcome these problems due to limitations in the interfaces adopted for controlling the prosthesis and to the lack of force or tactile feedback, thus limiting hand grasp capabilities. This paper presents a literature review on needs analysis of upper limb prosthesis users, and points out the main critical aspects of the current prosthetic solutions, in terms of users satisfaction and activities of daily living they would like to perform with the prosthetic device. The ultimate goal is to provide design inputs in the prosthetic field and, contemporary, increase user satisfaction rates and reduce device abandonment. A list of requirements for upper limb prostheses is proposed, grounded on the performed analysis on user needs. It wants to (i) provide guidelines for improving the level of acceptability and usefulness of the prosthesis, by accounting for hand functional and technical aspects; (ii) propose a control architecture of PNS-based prosthetic systems able to satisfy the analyzed user wishes; (iii) provide hints for improving the quality of the methods (e.g., questionnaires) adopted for understanding the user satisfaction with their prostheses. PMID:27242413

Image segmentation for enhancing symbol recognition in prosthetic vision.

PubMed

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.

Management of External Hemorrhage in Tactical Combat Casualty Care: Chitosan-Based Hemostatic Gauze Dressings. TCCC Guidelines Change 13-05

DTIC Science & Technology

2014-09-23

dramatically decreased. Coagulation parameters improved significantly over the next 36 hours. Muzzi et al./2012 CEG Acute prosthetic endocarditis ; 4 months...prosthetic endocarditis ; 4 months post aortic dissection surgery Preoperative IV heparin with impaired coagulation state. Yes; discharged

76 FR 64429 - Advisory Committee on Prosthetics and Special-Disabilities Programs; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-18

... research services available to the Committee. Additionally, the Committee will discuss future agenda topics... state-of-the art prosthetics and the associated rehabilitation research, development, and evaluation of... will be briefed by the Chief Disability and Medical Assessment Officer; Physical Therapy Program...

OSU-Okmulgee's Orthotics and Prosthetics Technician Program Thrives

ERIC Educational Resources Information Center

Smith, Sharon

2007-01-01

Students in the Orthotics and Prosthetics Technician Program at Oklahoma State University (OSU)-Okmulgee are provided with opportunities to develop multiple skill sets coveted by employers that will land them jobs in the industry as technicians, fitters or pedorthists. The program was recently restructured to become a technically based orthotic…

Development of regenerative peripheral nerve interfaces for motor control of neuroprosthetic devices

NASA Astrophysics Data System (ADS)

Kemp, Stephen W. P.; Urbanchek, Melanie G.; Irwin, Zachary T.; Chestek, Cynthia A.; Cederna, Paul S.

2017-05-01

Traumatic peripheral nerve injuries suffered during amputation commonly results in debilitating neuropathic pain in the affected limb. Modern prosthetic technologies allow for intuitive, simultaneous control of multiple degrees of freedom. However, these state-of-the-art devices require separate, independent control signals for each degree of freedom, which is currently not possible. As a result, amputees reject up to 75% of myoelectric devices preferring instead to use body-powered artificial limbs which offer subtle sensory feedback. Without meaningful and intuitive sensory feedback, even the most advanced myoelectric prostheses remain insensate, burdensome, and are associated with enormous cognitive demand and mental fatigue. The ideal prosthetic device is one which is capable of providing intuitive somatosensory feedback essential for interaction with the environment. Critical to the design of such a bioprosthetic device is the development of a reliable biologic interface between human and machine. This ideal patient-prosthetic interface allows for transmission of both afferent somatosensory information and efferent motor signals for a closed-loop feedback system of neural control. Our lab has developed the Regenerative Peripheral Nerve Interface (RPNI) as a biologic nerve interface designed for stable integration of a prosthetic device with transected peripheral nerves in a residual limb. The RPNI is constructed by surgically implanting the distal end of a transected peripheral nerve into an autogenous muscle graft. Animal experiments in our lab have shown recording of motor signals from RPNI's implanted into both rodents and monkeys. Here, we achieve high amplitude EMG signals with a high signal to noise (SNR) ratio.

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

PubMed

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.

Upper extremity transplantation: current concepts and challenges in an emerging field.

PubMed

Elliott, River M; Tintle, Scott M; Levin, L Scott

2014-03-01

Loss of an isolated upper limb is an emotionally and physically devastating event that results in significant impairment. Patients who lose both upper extremities experience profound disability that affects nearly every aspect of their lives. While prosthetics and surgery can eventually provide the single limb amputee with a suitable assisting hand, limited utility, minimal haptic feedback, weight, and discomfort are persistent problems with these techniques that contribute to high rates of prosthetic rejection. Moreover, despite ongoing advances in prosthetic technology, bilateral amputees continue to experience high levels of dependency, disability, and distress. Hand and upper extremity transplantation holds several advantages over prosthetic rehabilitation. The missing limb is replaced with one of similar skin color and size. Sensibility, voluntary motor control, and proprioception are restored to a greater degree, and afford better dexterity and function than prosthetics. The main shortcomings of transplantation include the hazards of immunosuppression, the complications of rejection and its treatment, and high cost. Hand and upper limb transplantation represents the most commonly performed surgery in the growing field of Vascularized Composite Allotransplantation (VCA). As upper limb transplantation and VCA have become more widespread, several important challenges and controversies have emerged. These include: refining indications for transplantation, optimizing immunosuppression, establishing reliable criteria for monitoring, diagnosing, and treating rejection, and standardizing outcome measures. This article will summarize the historical background of hand transplantation and review the current literature and concepts surrounding it.

Mandible reconstruction: History, state of the art and persistent problems.

PubMed

Ferreira, José J; Zagalo, Carlos M; Oliveira, Marta L; Correia, André M; Reis, Ana R

2015-06-01

Mandibular reconstruction has been experiencing an amazing evolution. Several different approaches are used to reconstruct this bone and therefore have a fundamental role in the recovery of oral functions. This review aims to highlight the persistent problems associated with the approaches identified, whether bone grafts or prosthetic devices are used. A brief summary of the historical evolution of the surgical procedures is presented, as well as an insight into possible future pathways. A literature review was conducted from September to December 2012 using the PubMed database. The keyword used was "mandible reconstruction." Articles published in the last three years were included as well as the relevant references from those articles and the "historical articles" were referred. This research resulted in a monograph that this article aims to summarize. Titanium plates, bone grafts, pediculate flaps, free osteomyocutaneous flaps, rapid prototyping, and tissue engineering strategies are some of the identified possibilities. The classical approaches present considerable associated morbidity donor-site-related problems. Research that results in the development of new prosthetics devices is needed. A new prosthetic approach could minimize the identified problems and offer the patients more predictable, affordable, and comfortable solutions. This review, while affirming the evolution and the good results found with the actual approaches, emphasizes the negative aspects that still subsist. Thus, it shows that mandible reconstruction is not a closed issue. On the contrary, it remains as a research field where new findings could have a direct positive impact on patients' life quality. The identification of the persistent problems reveals the characteristics to be considered in a new prosthetic device. This could overcome the current difficulties and result in more comfortable solutions. Medical teams have the responsibility to keep patients informed about the predictable problems related with each elected approach, even understanding that a perfect reconstruction is a secondary goal when compared with maintenance of life. © The International Society for Prosthetics and Orthotics 2014.

Salmonella Typhimurium gastroenteritis leading to chronic prosthetic vascular graft infection.

PubMed

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.

Use of the Internet for educational applications in prosthodontics.

PubMed

van Putten, M C

1996-08-01

Internet is the common term for the information superhighway. The Internet has become a major information resource for educational, governmental, and business institutions. This article reviews the current operation of the Internet as a background for discussing educational opportunities for instruction in prosthodontics. Electronic mail, news groups, file transfer protocol, Gopher, and network navigators are discussed. The use of the World Wide Web for educational purposes by The Ohio State University College of Dentistry Department of Restorative and Prosthetic Dentistry is described.

Standards, Regulation and Registration of Dental Laboratories. An Industry Update.

PubMed

Giovannone, Paul L

2015-01-01

State dental associations are showing increased interest in maintaining current standards and regulations affecting the dental laboratory industry as mandated by the Food and Drug Administration. The domestic dental laboratory industry is being significantly stressed by foreign competition, rapid technology development and unprecedented consolidation, which are changing the way that prosthetic devices and restorations are manufactured and delivered to dentists. Of paramount importance to the prescribing dentist is the accurate documentation of the source and materials being used in prostheses being delivered to patients.

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

PubMed

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.

Comparison of using different bridge prosthetic designs for partial defect restoration through mathematical modeling.

PubMed

Styranivska, Oksana; Kliuchkovska, Nataliia; Mykyyevych, Nataliya

2017-01-01

To analyze the stress-strain states of bone and abutment teeth during the use of different prosthetic designs of fixed partial dentures with the use of relevant mathematical modeling principles. The use of Comsol Multiphysics 3.5 (Comsol AB, Sweden) software during the mathematical modeling of stress-strain states provided numerical data for analytical interpretation in three different clinical scenarios with fixed dentures and different abutment teeth and demountable prosthetic denture with the saddle-shaped intermediate part. Microsoft Excel Software (Microsoft Office 2017) helped to evaluate absolute mistakes of stress and strain parameters of each abutment tooth during three modeled scenarios and normal condition and to summarize data into the forms of tables. In comparison with the fixed prosthetic denture supported by the canine, first premolar, and third molar, stresses at the same abutment teeth with the use of demountable denture with the saddle-shaped intermediate part decreased: at the mesial abutment tooth by 2.8 times, at distal crown by 6.1 times, and at the intermediate part by 11.1 times, respectively, the deformation level decreased by 3.1, 1.9, and 1.4 times at each area. The methods of mathematical modeling proved that complications during the use of fixed partial dentures based on the overload effect of the abutment teeth and caused by the deformation process inside the intermediate section of prosthetic construction.

Granulicatella adiacens prosthetic hip joint infection after dental treatment.

PubMed

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.

A review of functional outcomes related to prosthetic treatment after maxillary and mandibular reconstruction in patients with head and neck cancer.

PubMed

Tang, Judith A Lam; Rieger, Jana M; Wolfaardt, Johan F

2008-01-01

This review examined literature that reported functional outcomes across 3 categories of prosthetic treatment after microvascular reconstruction of the maxilla and mandible: (1) conventional dental/tissue-supported prosthesis, (2) implant-retained prosthesis, and (3) no prosthesis. Library databases were searched for articles related to reconstruction of the maxilla and mandible, and references of selected articles were hand searched. Relevant literature was identified and reviewed with criteria specified a priori. Forty-nine articles met the inclusion criteria. Twelve articles reported on function after maxillary reconstruction, with the majority of articles reporting on outcomes for 1 to 6 subjects. Thirty-nine articles reported on function after mandibular reconstruction. Speech outcomes were satisfactory across all groups. Swallowing reports indicated that many patients who received either type of prosthetic rehabilitation resumed a normal diet, whereas those without prosthetic rehabilitation were often restricted to liquid diets or feeding tubes. Patients without prosthetic rehabilitation reportedly had poor masticatory ability, whereas conventional prosthetic treatment allowed some recovery of mastication and implant-retained prosthetic treatment resulted in the most favorable masticatory outcomes. Quality-of-life outcomes were similar across all patients. Several limitations of the current literature prevented definitive conclusions from being reached within this review, especially regarding maxillary reconstruction. However, recognition of these limitations can direct functional assessment for the future.

Getting signals into the brain: visual prosthetics through thalamic microstimulation.

PubMed

Pezaris, John S; Eskandar, Emad N

2009-07-01

Common causes of blindness are diseases that affect the ocular structures, such as glaucoma, retinitis pigmentosa, and macular degeneration, rendering the eyes no longer sensitive to light. The visual pathway, however, as a predominantly central structure, is largely spared in these cases. It is thus widely thought that a device-based prosthetic approach to restoration of visual function will be effective and will enjoy similar success as cochlear implants have for restoration of auditory function. In this article the authors review the potential locations for stimulation electrode placement for visual prostheses, assessing the anatomical and functional advantages and disadvantages of each. Of particular interest to the neurosurgical community is placement of deep brain stimulating electrodes in thalamic structures that has shown substantial promise in an animal model. The theory of operation of visual prostheses is discussed, along with a review of the current state of knowledge. Finally, the visual prosthesis is proposed as a model for a general high-fidelity machine-brain interface.

Speech and Swallowing Data in Individual Patients Who Underwent Glossectomy after Prosthetic Rehabilitation

PubMed Central

Sennes, Luiz Ubirajara

2016-01-01

Maintaining oral function in patients undergoing glossectomy boosts interventions such as prosthetic rehabilitation. However, current literature still fails in the presentation of results of prosthetic rehabilitation in relation to speech or swallowing. The objective of this research is to evaluate the effectiveness of prosthetic rehabilitation on voice, speech, and swallowing in patients undergoing glossectomy by performing a systematic literature review and meta-analysis of individual cases. Studies were identified by relevant electronic database and included all dates available. The criteria used were sample with any n; resection due to malignant tumors, restricted to tongue and/or floor of mouth; type of prosthetic rehabilitation; and description of the oral functions outcomes with prosthesis. For the meta-analysis of individual data, associations between the variables of interest and the type of prosthesis were evaluated. Thirty-three of 471 articles met the selection criteria. Results on speech and/or voice and swallowing were reported in 27 and 28 articles, respectively. There were improvement of speech intelligibility and swallowing in 96 patients and in 73 patients, respectively, with prosthesis. Based on the available evidences, this article showed that prosthetic rehabilitation was able to improve oral functions and can be a strategy used with surgical reconstruction in selected cases. PMID:28042295

Preferences for rehabilitation services among women with major limb amputations.

PubMed

Elnitsky, Christine A; Latlief, Gail A; Andrews, Erin E; Adams-Koss, Laurel B; Phillips, Samuel L

2013-01-01

We present five cases of adult females with major limb amputations, their concerns and preferences for services across the life span. A convenience sample of five veteran and nonveteran women aged 19-58 with major limb amputations participating in a regional VA Prosthetics Conference in 2010 took part in a panel interview. The concerns identified by these women as high priorities included independence and participation in a full range of life activities, limitations in access, patient decision-making and body image concerns, and preferences for selected services. Maximizing function and quality of life for women amputees requires identifying patient preferences for rehabilitation and prosthetic services. Lessons learned could inform development of clinic-based rehabilitation care, prosthetic services, and studies of women with major limb amputations. As the current conflicts in Iraq and Afghanistan wind down, the number of women veterans seeking rehabilitation and prosthetic services will increase. With this information, rehabilitation and prosthetic service providers and organizations will be uniquely positioned to provide prevention and treatment of amputations for this growing population of women veterans in national care delivery systems and in communities. An open-ended facilitated discussion among a panel of women with major limb amputations provided insights for providers and organizations with respect to needs, concerns, and preferences for rehabilitation and prosthetic services. © 2013 Association of Rehabilitation Nurses.

User surveys support designing a prosthetic wrist that incorporates the Dart Thrower's Motion.

PubMed

Davidson, Matthew; Bodine, Cathy; Weir, Richard F Ff

2018-03-07

Prosthetic devices are not meeting the needs of people with upper limb amputations. Due to controlsidelimitations, prosthetic wrists cannot yet be fully articulated. This study sought to determine which wrist motions users felt were most important for completing activities of daily living. We specifically invstigated whether adding a combinationof flexion and deviation known as the Dart Thrower's Motion to a prosthetic wrist would help improve functionality. Fifteen participants with a trans-radial amputation, aged 25-64 years, who use a prosthesis completed an online survey and answered interview questions to determine which types of tasks pose particular challenges. Participants were asked what kinds of improvements they would like to see in a new prosthesis. A subset of five participants were interviewed in-depth to provide further information about difficulties they face using their device. The survey showed that participants had difficulty performing activities of daily living that involve a combination of wrist flexion and deviation known as the "Dart Throwers Motion". Interview responses confirmed that users have difficulty performing these tasks, especially those that require tools. Additionally, users said that they were more interested in having flexion and deviation than rotation in a prosthetic wrist. This research indicates that including the Dart Thrower's Motion in future designs of prosthetic wrists would improve these devices and people with upper limb amputations would be excited to see this improvement in their devices. Implications for Rehabilitation • Over one third of people with upper limb amputations do not use a prosthesis because prosthetic devices do not meet their needs.• The number of motions possible in state of the art prosthetic devices is limited by the small number of control sites available.• The Dart Thrower?s Motion is a wrist motion used for many activities of daily living but unavailable in commercial prosthetics leading many prosthetics users to have difficulty with these tasks.• Prosthetic use, and therefore quality of life, could be improved by including the Dart Thrower's Motion in a prosthesis.

Power feasibility of implantable digital spike sorting circuits for neural prosthetic systems.

PubMed

Zumsteg, Zachary S; Kemere, Caleb; O'Driscoll, Stephen; Santhanam, Gopal; Ahmed, Rizwan E; Shenoy, Krishna V; Meng, Teresa H

2005-09-01

A new class of neural prosthetic systems aims to assist disabled patients by translating cortical neural activity into control signals for prosthetic devices. Based on the success of proof-of-concept systems in the laboratory, there is now considerable interest in increasing system performance and creating implantable electronics for use in clinical systems. A critical question that impacts system performance and the overall architecture of these systems is whether it is possible to identify the neural source of each action potential (spike sorting) in real-time and with low power. Low power is essential both for power supply considerations and heat dissipation in the brain. In this paper we report that state-of-the-art spike sorting algorithms are not only feasible using modern complementary metal oxide semiconductor very large scale integration processes, but may represent the best option for extracting large amounts of data in implantable neural prosthetic interfaces.

Powered ankle-foot prosthesis to assist level-ground and stair-descent gaits.

PubMed

Au, Samuel; Berniker, Max; Herr, Hugh

2008-05-01

The human ankle varies impedance and delivers net positive work during the stance period of walking. In contrast, commercially available ankle-foot prostheses are passive during stance, causing many clinical problems for transtibial amputees, including non-symmetric gait patterns, higher gait metabolism, and poorer shock absorption. In this investigation, we develop and evaluate a myoelectric-driven, finite state controller for a powered ankle-foot prosthesis that modulates both impedance and power output during stance. The system employs both sensory inputs measured local to the external prosthesis, and myoelectric inputs measured from residual limb muscles. Using local prosthetic sensing, we first develop two finite state controllers to produce biomimetic movement patterns for level-ground and stair-descent gaits. We then employ myoelectric signals as control commands to manage the transition between these finite state controllers. To transition from level-ground to stairs, the amputee flexes the gastrocnemius muscle, triggering the prosthetic ankle to plantar flex at terminal swing, and initiating the stair-descent state machine algorithm. To transition back to level-ground walking, the amputee flexes the tibialis anterior muscle, triggering the ankle to remain dorsiflexed at terminal swing, and initiating the level-ground state machine algorithm. As a preliminary evaluation of clinical efficacy, we test the device on a transtibial amputee with both the proposed controller and a conventional passive-elastic control. We find that the amputee can robustly transition between the finite state controllers through direct muscle activation, allowing rapid transitioning from level-ground to stair walking patterns. Additionally, we find that the proposed finite state controllers result in a more biomimetic ankle response, producing net propulsive work during level-ground walking and greater shock absorption during stair descent. The results of this study highlight the potential of prosthetic leg controllers that exploit neural signals to trigger terrain-appropriate, local prosthetic leg behaviors.

Dental prosthetic status and prosthetic needs of institutionalised elderly population in oldage homes of jabalpur city, madhya pradesh, India.

PubMed

Deogade, Suryakant C; Vinay, S; Naidu, Sonal

2013-12-01

Oral disorders are cumulative throughout life and hence unfavourable outcomes are likely to be greatest among the elderly. A descriptive cross-sectional study was conducted among institutionalized geriatric population in old-age homes of Jabalpur city, Madhya Pradesh, to assess their prosthetic status and prosthetic needs. A cross-sectional survey was conducted in all the four old-age homes of Jabalpur city, Madhya Pradesh state, India. All residents aged 60 years and above formed the study population. The recording of prosthetic status and prosthetic needs was carried out according to the World Health Organisation (WHO) Oral Health Assessment Form (1997). A total of 224 individuals were included in the study of which 123 were females and 101 were males. Seventy five percent of the females and 55 % of the males had no prostheses in their upper arch and 61 % of the females and 76 % of the males had no prostheses in their lower arch. More number of males presented with 'Bridges' in their upper arch when compared to females (P value = 0.006). Highest prosthetic need in males was multi-unit prosthesis (42 % in upper arch and 41 % in lower arch) whereas, females' required full prosthesis (39 % in both the upper arch and lower arches). Ageing presents some formidable challenges, particularly with the institutionalised. This study clearly demonstrates a high insufficiency of prosthetic care among the institutionalized elderly population. Any preparation towards the provision of oral health care should not be limited to treatment alone but, more importantly focus on empowering this elderly community with information and education programmes.

Local signaling from a retinal prosthetic in a rodent retinitis pigmentosa model in vivo

NASA Astrophysics Data System (ADS)

Fransen, James W.; Pangeni, Gobinda; Pardue, Machelle T.; McCall, Maureen A.

2014-08-01

Objective. In clinical trials, retinitis pigmentosa patients implanted with a retinal prosthetic device show enhanced spatial vision, including the ability to read large text and navigate. New prosthetics aim to increase spatial resolution by decreasing pixel/electrode size and limiting current spread. To examine spatial resolution of a new prosthetic design, we characterized and compared two photovoltaic array (PVA) designs and their interaction with the retina after subretinal implantation in transgenic S334ter line 3 rats (Tg S334ter-3). Approach. PVAs were implanted subretinally at two stages of degeneration and assessed in vivo using extracellular recordings in the superior colliculus (SC). Several aspects of this interaction were evaluated by varying duration, irradiance and position of a near infrared laser focused on the PVA. These characteristics included: activation threshold, response linearity, SC signal topography and spatial localization. The major design difference between the two PVA designs is the inclusion of local current returns in the newer design. Main results. When tested in vivo, PVA-evoked response thresholds were independent of pixel/electrode size, but differ between the new and old PVA designs. Response thresholds were independent of implantation age and duration (⩽7.5 months). For both prosthesis designs, threshold intensities were within established safety limits. PVA-evoked responses require inner retina synaptic transmission and do not directly activate retinal ganglion cells. The new PVA design evokes local retinal activation, which is not found with the older PVA design that lacks local current returns. Significance. Our study provides in vivo evidence that prosthetics make functional contacts with the inner nuclear layer at several stages of degeneration. The new PVA design enhances local activation within the retina and SC. Together these results predict that the new design can potentially harness the inherent processing within the retina and is likely to produce higher spatial resolution in patients.

[The incidence and prevalence of complications after urogynaecological and reconstructive pelvic floor prosthetic surgery and management of these complications in women].

PubMed

Martan, A; Svabík, K; Masata, J

2007-12-01

The aim of this article is to review the incidence and prevalence of complications after prosthetic surgery for POP (pelvic organ prolaps) and USI (urodynamic stress incontinence) and to introduce diagnostic and therapeutic advice into clinical practice. Review article. Gynecological and Obstetric Clinic, 1st LF UK and VFN, Prague. Summary of complications, recent findings, opinions and specific diagnostic and therapeutic recommendations with special focus to vaginal erosion, post-operative voiding difficulties, persisting leakage of urine and de novo urgency. In the last decade the surgical treatment of female USI by prosthetic slings procedures has been shown to be effective with high cure rate and low morbidity. Similary, prosthetic reconstruction of pelvic organ prolapse through the different compartments has been introduced into clinical practice with good anatomical and promising functional results. The article is structured to the different sections, describing the epidemiology and management of complications after prosthetic slings procedures and after vaginal prosthetic treatment of pelvic organ prolapse. The effect of various operations of pelvic floor and USI using synthetic implants may differ, depending on the material of the implant used. Current recommendation for the implants material: a light-weight, flexible polypropylene; Amid's classification: type 1, i.e macro-porous, monofilament material. The advantage of surgical treatment of pelvic floor defect using implants comprises a low percentage of recurrence of the descensus.

Treatment Challenges of Prosthetic Hip Infection with Associated Iliacus Muscle Abscess: Report of 5 Cases and Literature Review.

PubMed

Lawrenz, Joshua M; Mesko, Nathan W; Higuera, Carlos A; Molloy, Robert M; Simpfendorfer, Claus; Babic, Maja

2017-01-01

Prosthetic joint infection is an unfortunate though well-recognized complication of total joint arthroplasty. An iliacus and/or iliopsoas muscle abscess is a rarely documented presentation of hip prosthetic joint infection. It is thought an unrecognized retroperitoneal nidus of infection can be a source of continual seeding of the prosthetic hip joint, prolonging attempts to eradicate infection despite aggressive debridement and explant attempts. The current study presents five cases demonstrating this clinical scenario, and discusses various treatment challenges. In each case we report the patient's clinical history, pertinent imaging, management and outcome. Diagnosis of the iliacus muscle abscess was made using computed tomography imaging. In brief, the mean number of total drainage procedures (open and percutaneous) per patient was 4.2, and outcomes consisted of one patient with a hip girdlestone, two patients with delayed revisions, and two patients with retained prosthesis. All patients ended with functional pain and on oral antibiotic suppression with an average follow up of 18 months. This article highlights an iliacus muscle abscess as an unrecognized source of infection to a prosthetic hip. It demonstrates resilience to standard treatment protocols for prosthetic hip infection, and is associated with poor patient outcomes. Aggressive surgical debridement appears to remain critical to treatment success, and early retroperitoneal debridement of the abscess should be considered.

Development and preliminary evaluation of a new anatomically based prosthetic alignment method for below-knee prosthesis.

PubMed

Tafti, Nahid; Karimlou, Masoud; Mardani, Mohammad Ali; Jafarpisheh, Amir Salar; Aminian, Gholam Reza; Safari, Reza

2018-04-20

The objectives of current study were to a) assess similarities and relationships between anatomical landmark-based angles and distances of lower limbs in unilateral transtibial amputees and b) develop and evaluate a new anatomically based static prosthetic alignment method. First sub-study assessed the anthropometrical differences and relationships between the lower limbs in the photographs taken from amputees. Data were analysed via paired t-test and regression analysis. Results show no significant differences in frontal and transverse planes. In the sagittal plane, the anthropometric parameters of the amputated limb were significantly correlated to the corresponding variables of the sound limb. The results served as bases for the development of a new prosthetic alignment method. The method was evaluated on a single subject study. Prosthetic alignment carried out by an experienced prosthetist was compared with such alignment adjusted by an inexperienced prosthetist but with the use of the developed method. In sagittal and frontal planes, the socket angle was tuned with respect to the shin angle, and the position of the prosthetic foot was tuned in relation to the pelvic landmarks. Further study is needed to assess the proposed method on a larger sample of amputees and prosthetists.

Historical Aspects of Inner Ear Anatomy and Biology that Underlie the Design of Hearing and Balance Prosthetic Devices.

PubMed

Van De Water, Thomas R

2012-11-01

This review presents some of the major historical events that advanced the body of knowledge of the anatomy of the inner ear and its sensory receptors as well as the biology of these receptors that underlies the sensory functions of hearing and balance. This knowledge base of the inner ear's structure/function has been an essential factor for the design and construction of prosthetic devices to aid patients with deficits in their senses of hearing and balance. Prosthetic devices are now available for severely hearing impaired and deaf patients to restore hearing and are known as cochlear implants and auditory brain stem implants. A prosthetic device for patients with balance disorders is being perfected and is in an animal model testing phase with another prosthetic device for controlling intractable dizziness in Meniere's patients currently being evaluated in clinical testing. None of this would have been possible without the pioneering studies and discoveries of the investigators mentioned in this review and with the work of many other talented investigators to numerous to be covered in this review. Copyright © 2012 Wiley Periodicals, Inc.

A patterned microtexture to reduce friction and increase longevity of prosthetic hip joints

PubMed Central

Chyr, Anthony; Qiu, Mingfeng; Speltz, Jared; Jacobsen, Ronald L.; Sanders, Anthony P.; Raeymaekers, Bart

2014-01-01

More than 285,000 total hip replacement surgeries are performed in the US each year. Most prosthetic hip joints consist of a cobalt-chromium (CoCr) femoral head that articulates with a polyethylene acetabular component, lubricated with synovial fluid. The statistical survivorship of these metal-on-polyethylene prosthetic hip joints declines significantly after 10 to 15 years of use, primarily as a result of polyethylene wear and wear debris incited disease. The current engineering paradigm to increase the longevity of prosthetic hip joints is to improve the mechanical properties of the polyethylene component, and to manufacture ultra-smooth articulating surfaces. In contrast, we show that adding a patterned microtexture to the ultra-smooth CoCr femoral head reduces friction when articulating with the polyethylene acetabular liner. The microtexture increases the load-carrying capacity and the thickness of the joint lubricant film, which reduces contact between the articulating surfaces. As a result, friction and wear is reduced. We have used a lubrication model to design the geometry of the patterned microtexture, and experimentally demonstrate reduced friction for the microtextured compared to conventional smooth surrogate prosthetic hip joints. PMID:25013240

Comparison of mechanical energy profiles of passive and active below-knee prostheses: a case study.

PubMed

Takahashi, Kota Z; Horne, John R; Stanhope, Steven J

2015-04-01

With the recent technological advancements of prosthetic lower limbs, there is currently a great desire to objectively evaluate existing prostheses. Using a novel biomechanical analysis, the purpose of this case study was to compare the mechanical energy profiles of anatomical and two disparate prostheses: a passive prosthesis and an active prosthesis. An individual with a transtibial amputation who customarily wears a passive prosthesis (Elation, Össur) and an active prosthesis (BiOM, iWalk, Inc.) and 11 healthy subjects participated in an instrumented gait analysis. The total mechanical power and work of below-knee structures during stance were quantified using a unified deformable segment power analysis. Active prosthesis generated greater peak power and total positive work than passive prosthesis and healthy anatomical limbs. The case study will enhance future efforts to objectively evaluate prosthetic functions during gait in individuals with transtibial amputations. A prosthetic limb should closely replicate the mechanical energy profiles of anatomical limbs. The unified deformable (UD) analysis may be valuable to facilitate future clinical prescription and guide fine adjustments of prosthetic componentry to optimize gait outcomes. © The International Society for Prosthetics and Orthotics 2014.

Neural interfaces for control of upper limb prostheses: the state of the art and future possibilities.

PubMed

Schultz, Aimee E; Kuiken, Todd A

2011-01-01

Current treatment of upper limb amputation restores some degree of functional ability, but this ability falls far below the standard set by the natural arm. Although acceptance rates can be high when patients are highly motivated and receive proper training and care, current prostheses often fail to meet the daily needs of amputees and frequently are abandoned. Recent advancements in science and technology have led to promising methods of accessing neural information for communication or control. Researchers have explored invasive and noninvasive methods of connecting with muscles, nerves, or the brain to provide increased functionality for patients experiencing disease or injury, including amputation. These techniques offer hope of more natural and intuitive prosthesis control, and therefore increased quality of life for amputees. In this review, we discuss the current state of the art of neural interfaces, particularly those that may find application within the prosthetics field. Copyright © 2011 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Prosthetic model, but not stiffness or height, affects the metabolic cost of running for athletes with unilateral transtibial amputations.

PubMed

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 < 0.001] and Össur Flex-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 < 0.001) averaged from both legs. Metabolic cost was reduced with more symmetric peak vertical ground reaction forces (β = 0.007; P = 0.003) but was unrelated to stride kinematic symmetry ( P ≥ 0.636). Therefore, prosthetic recommendations based on symmetric stride kinematics do not necessarily minimize the metabolic cost of 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 increased in-series surface stiffness, biological limb stiffness for athletes with unilateral transtibial amputations is positively correlated with increased in-series (prosthetic) stiffness.

Current strategies with 1-stage prosthetic breast reconstruction

PubMed Central

2015-01-01

Background 1-stage prosthetic breast reconstruction is gaining traction as a preferred method of breast reconstruction in select patients who undergo mastectomy for cancer or prevention. Methods Critical elements to the procedure including patient selection, technique, surgical judgment, and postoperative care were reviewed. Results Outcomes series reveal that in properly selected patients, direct-to-implant (DTI) reconstruction has similar low rates of complications and high rates of patient satisfaction compared to traditional 2-stage reconstruction. Conclusions 1-stage prosthetic breast reconstruction may be the procedure of choice in select patients undergoing mastectomy. Advantages include the potential for the entire reconstructive process to be complete in one surgery, the quick return to normal activities, and lack of donor site morbidity. PMID:26005643

Redox activity distinguishes solid-state electron transport from solution-based electron transfer in a natural and artificial protein: cytochrome C and hemin-doped human serum albumin.

PubMed

Amdursky, Nadav; Ferber, Doron; Pecht, Israel; Sheves, Mordechai; Cahen, David

2013-10-28

Integrating proteins in molecular electronic devices requires control over their solid-state electronic transport behavior. Unlike "traditional" electron transfer (ET) measurements of proteins that involve liquid environments and a redox cycle, no redox cofactor is needed for solid-state electron transport (ETp) across the protein. Here we show the fundamental difference between these two approaches by macroscopic area measurements, which allow measuring ETp temperature dependence down to cryogenic temperatures, via cytochrome C (Cyt C), an ET protein with a heme (Fe-porphyrin) prosthetic group as a redox centre. We compare the ETp to electrochemical ET measurements, and do so also for the protein without the Fe (with metal-free porphyrin) and without porphyrin. As removing the porphyrin irreversibly alters the protein's conformation, we repeat these measurements with human serum albumin (HSA), 'doped' (by non-covalent binding) with a single hemin equivalent, i.e., these natural and artificial proteins share a common prosthetic group. ETp via Cyt C and HSA-hemin are very similar in terms of current magnitude and temperature dependence, which suggests similar ETp mechanisms via these two systems, thermally activated hopping (with ~0.1 eV activation energy) >190 K and tunneling by superexchange <190 K. Also, ET rates to and from the Fe redox centres (Fe(2+) <=> Fe(3+) + e(-)), measured by electrochemistry of HSA-hemin are only 4 times lower than those for Cyt C. However, while removing the Fe redox centre from the porphyrin ring markedly affects the ET rate, it hardly changes the ETp currents through these proteins, while removing the macrocycle (from HSA, which retains its conformation) significantly reduces ETp efficiency. These results show that solid-state ETp across proteins does not require the presence of a redox cofactor, and that while for ET the Fe ion is the main electron mediator, for ETp the porphyrin ring has this function.

Oral health-related quality of life and prosthetic status of nursing home residents with or without dementia.

PubMed

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 <24). Parametric bivariate statistics and logistic regression models were used to analyze data at P <0.05. A total of 169 participants were included in this study. The mean age of the participants was 82.9 years. A total of some 70% of the sample was living with dementia. The mean GOHAI score along the sample was 49.1 (8.3), and 41% of the sample reported substantially compromised OHRQoL (GOHAI <50). OHRQoL was statistically similar for people with or without dementia ( P =0.234); objective oral 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 <0.05). The OHRQoL of elderly 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.

Risks and Challenges of Surgery for Aortic Prosthetic Valve Endocarditis.

PubMed

Grubitzsch, Herko; Tarar, Waharat; Claus, Benjamin; Gabbieri, Davide; Falk, Volkmar; Christ, Torsten

2018-03-01

Prosthetic valve endocarditis is the most severe form of infective endocarditis. This study assessed the risks and challenges of surgery for aortic prosthetic valve endocarditis. In total, 116 consecutive patients (98 males, age 65.2±12.7years), who underwent redo-surgery for active aortic prosthetic valve endocarditis between 2000 and 2014, were reviewed. Cox regression analysis was used to identify factors for aortic root destructions as well as for morbidity and mortality. Median follow-up was 3.8 years (0-13.9 years). Aortic root destructions (42 limited and 29 multiple lesions) were associated with early prosthetic valve endocarditis and delayed diagnosis (≥14 d), but not with mortality. There were 16 (13.8%) early (≤30 d) and 32 (27.6%) late (>30 days) deaths. Survival at 1, 5, and 10 years was 72±4.3%, 56±5.4%, and 46±6.4%, respectively. The cumulative incidence of death, reinfection, and reoperation was 19.0% at 30days and 36.2% at 1year. Delayed diagnosis, concomitant procedures, and EuroSCORE II >20% were predictors for early mortality and need for mechanical circulatory support, age >70years, and critical preoperative state were predictors for late mortality. In their absence, survival at 10 years was 70±8.4%. Reinfections and reoperations occurred more frequently if ≥1 risk factor for endocarditis and aortic root destructions were present. At 10 years, freedom from reinfection and reoperation was 89±4.2% and 91±4.0%. The risks of death, reinfection, and reoperation are significant within the first year after surgery for aortic prosthetic valve endocarditis. Early diagnosis and aortic root destructions are the most important challenges, but advanced age, critical preoperative state, and the need for mechanical circulatory support determine long-term survival. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

The effect that energy storage and return feet have on the propulsion of the body: a pilot study.

PubMed

Crimin, Anthony; McGarry, Anthony; Harris, Elena Jane; Solomonidis, Stephan Emanuel

2014-09-01

A variety of energy storage and return prosthetic feet are currently available for use within lower limb prostheses. Designs claim to provide a beneficial energy return during push-off, but the extent to which this occurs remains disputed. Techniques currently used to measure energy storage, dissipation and return within the structure of the prosthetic foot are debatable, with limited evidence to support substantial elastic energy storage and return from existing designs. The aim of this study was to evaluate the performance of energy storage and return foot designs through considering the ankle power during push-off and the effect on body centre of mass propulsion. To achieve this aim, the gait patterns of six trans-tibial prosthetic users wearing different designs of energy storage and return feet were analysed while ascending a ramp. Three examples of energy storage and return feet (suitable for moderate activity) were selected and randomly evaluated: the Blatchford's Epirus, Össur Assure and College Park Tribute feet. The power at the anatomical and mechanical ankle joints was integrated to evaluate the work done over the gait cycle. The direction of the inertial force, and therefore propulsion of the body centre of mass, was used to indicate the effect of the energy return by the energy storage and return feet. Results indicate that although energy storage and return feet may provide energy return, the work done around the prosthetic ankle indicates net power absorption. Therefore, the prosthetic limb is unable to contribute to the body centre of mass propulsion to the same extent as the biological limb. © IMechE 2014.

Acute Infection in Total Knee Arthroplasty: Diagnosis and Treatment

PubMed Central

Martínez-Pastor, Juan Carlos; Maculé-Beneyto, Francisco; Suso-Vergara, Santiago

2013-01-01

Infection is one of the most serious complications after total knee arthroplasty (TKA). The current incidence of prosthetic knee infection is 1-3%, depending on the series. For treatment and control to be more cost effective, multidisciplinary groups made up of professionals from different specialities who can work together to eradicate these kinds of infections need to be assembled. About the microbiology, Staphylococcus aureus and coagulase-negative staphylococcus were among the most frequent microorganisms involved (74%). Anamnesis and clinical examination are of primary importance in order to determine whether the problem may point to a possible acute septic complication. The first diagnosis may then be supported by increased CRP and ESR levels. The surgical treatment for a chronic prosthetic knee infection has been perfectly defined and standardized, and consists in a two-stage implant revision process. In contrast, the treatment for acute prosthetic knee infection is currently under debate. Considering the different surgical techniques that already exist, surgical debridement with conservation of the prosthesis and polythene revision appears to be an attractive option for both surgeon and patient, as it is less aggressive than the two-stage revision process and has lower initial costs. The different results obtained from this technique, along with prognosis factors and conclusions to keep in mind when it is indicated for an acute prosthetic infection, whether post-operative or haematogenous, will be analysed by the authors. PMID:23919094

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

PubMed

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.

Peri-prosthetic femoral fractures of hip or knee arthroplasty. Analysis of 34 cases and a review of Spanish series in the last 20 years.

PubMed

Gracia-Ochoa, M; Miranda, I; Orenga, S; Hurtado-Oliver, V; Sendra, F; Roselló-Añón, A

2016-01-01

To evaluate peri-prosthetic femoral fractures by analysing type of patient, treatment and outcomes, and to compare them with Spanish series published in the last 20 years. A retrospective review of the medical records of patients with peri-prosthetic femoral fractures treated in our hospital from 2010 to 2014, and telephone survey on the current status. A total of 34 peri-prosthetic femoral fractures were analysed, 20 in hip arthroplasty and 14 in knee arthroplasty. The mean age of the patients was 79.9 years, and 91% had previous comorbidity, with up to 36% having at least 3 prior systemic diseases. Mean hospital stay was 8.7 days, and was higher in surgically-treated than in conservative-treated patients. The majority (60.6%) of patients had complications, and mortality was 18%. Functional status was not regained in 61.5% of patients, and pain was higher in hip than in knee arthroplasty. Peri-prosthetic femoral fractures are increasing in frequency. This is due to the increasing number of arthroplasties performed and also to the increasing age of these patients. Treatment of these fractures is complex because of the presence of an arthroplasty component, low bone quality, and comorbidity of the patients. Peri-prosthetic femoral fractures impair quality of life. They need individualised treatment, and have frequent complications and mortality. Copyright © 2016 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

The quest for the bionic arm.

PubMed

Hutchinson, Douglas T

2014-06-01

The current state of research of upper extremity prosthetic devices is focused on creating a complete prosthesis with full motor and sensory function that will provide amputees with a near-normal human arm. Although advances are being made rapidly, many hurdles remain to be overcome before a functional, so-called bionic arm is a reality. Acquiring signals via nerve or muscle inputs will require either a reliable wireless device or direct wiring through an osseous-integrated implant. The best way to tap into the "knowledge" present in the peripheral nerve is yet to be determined. Copyright 2014 by the American Academy of Orthopaedic Surgeons.

Electromyography (EMG) signal recognition using combined discrete wavelet transform based adaptive neuro-fuzzy inference systems (ANFIS)

NASA Astrophysics Data System (ADS)

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.

Microbiological Aetiology, Epidemiology, and Clinical Profile of Prosthetic Joint Infections: Are Current Antibiotic Prophylaxis Guidelines Effective?

PubMed Central

Cheng, Allen C.; Buising, Kirsty L.; Choong, Peter F. M.

2012-01-01

Prosthetic joint infections remain a major complication of arthroplasty. At present, local and international guidelines recommend cefazolin as a surgical antibiotic prophylaxis at the time of arthroplasty. This retrospective cohort study conducted across 10 hospitals over a 3-year period (January 2006 to December 2008) investigated the epidemiology and microbiological etiology of prosthetic joint infections. There were 163 cases of prosthetic joint infection identified. From a review of the microbiological culture results, methicillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative staphylococci were isolated in 45% of infections. In addition, polymicrobial infections, particularly those involving Gram-negative bacilli and enterococcal species, were common (36%). The majority (88%) of patients received cefazolin as an antibiotic prophylaxis at the time of arthroplasty. In 63% of patients in this cohort, the microorganisms subsequently obtained were not susceptible to the antibiotic prophylaxis administered. The results of this study highlight the importance of ongoing reviews of the local ecology of prosthetic joint infection, demonstrating that the spectrum of pathogens involved is broad. The results should inform empirical antibiotic therapy. This report also provokes discussion about infection control strategies, including changing surgical antibiotic prophylaxis to a combination of glycopeptide and cefazolin, to reduce the incidence of infections due to methicillin-resistant staphylococci. PMID:22314530

[Acrylic resin reinforcement with metallic and nonmetallic inserts].

PubMed

Preoteasa, Elena; Murariu, Cătălina Măgureanu; Ionescu, Ecaterina; Preoteasa, Cristina Teodora

2007-01-01

In the current use of acrylic resin for removable dentures and orthodontic treatments we are frequently facing the fact of base fracture. The repairing of this, determine most of the time, discomfort of the patient, by excluding the prosthetic device, affecting the treatment, loosing patient's time, doctor's time, implying the dental laboratory and extra expenses. The causes of fractures are many, from clinical cases with some specific anatomic and functional particularities, or parafunctional, to the incorrect designing, manufacturing or wearing of the prosthetic part, being connected with the materials characteristics. The consequences and costs of these fractures are leading to unsatisfying results in some of the clinical cases, in presence of parafunctions like bruxism or clenching and specifically for the new types of prosthetic rehabilitation, on natural teeth or implants.

Medicare program; competitive acquisition for certain durable medical equipment, prosthetics, orthotics, and supplies (DMEPOS) and other issues. Final rule.

PubMed

2007-04-10

This final rule establishes competitive bidding programs for certain Medicare Part B covered items of durable medical equipment, prosthetics, orthotics, and supplies (DMEPOS) throughout the United States in accordance with sections 1847(a) and (b) of the Social Security Act. These competitive bidding programs, which will be phased in over several years, utilize bids submitted by DMEPOS suppliers to establish applicable payment amounts under Medicare Part B.

Shoulder arthroplasty in osteoarthritis: current concepts in biomechanics and surgical technique

PubMed Central

Merolla, G; Nastrucci, G; Porcellini, G

Shoulder arthroplasty is a technically demanding procedure to restore shoulder function in patients with severe osteoarthritis of the glenohumeral joint. The modern prosthetic system exploit the benefits of modularity and the availibility of additional sizes of the prosthetic components. In this paper we describe the biomechanics of shoulder arthroplasty and the technique for shoulder replacement including total shoulder arthroplasty (TSA) with all-polyethylene and metal-backed glenoid component, humeral head resurfacing and stemless humeral replacement. PMID:24251240

Evaluation of 3D printed anatomically scalable transfemoral prosthetic knee.

PubMed

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.

Surgery for rheumatic mitral valve disease in sub-saharan African countries: why valve repair is still the best surgical option.

PubMed

Mvondo, Charles Mve; Pugliese, Marta; Giamberti, Alessandro; Chelo, David; Kuate, Liliane Mfeukeu; Boombhi, Jerome; Dailor, Ellen Marie

2016-01-01

Rheumatic valve disease, a consequence of acute rheumatic fever, remains endemic in developing countries in the sub-Saharan region where it is the leading cause of heart failure and cardiovascular death, involving predominantly a young population. The involvement of the mitral valve is pathognomonic and mitral surgery has become the lone therapeutic option for the majority of these patients. However, controversies exist on the choice between valve repair or prosthetic valve replacement. Although the advantages of mitral valve repair over prosthetic valve replacement in degenerative mitral disease are well established, this has not been the case for rheumatic lesions, where the use of prosthetic valves, specifically mechanical devices, even in poorly compliant populations remains very common. These patients deserve more accurate evaluation in the choice of the surgical strategy which strongly impacts the post-operative outcomes. This report discusses the factors supporting mitral repair surgery in rheumatic disease, according to the patients' characteristics and the effectiveness of the current repair techniques compared to prosthetic valve replacement in developing countries.

Power feasibility of implantable digital spike-sorting circuits for neural prosthetic systems.

PubMed

Zumsteg, Zachary S; Ahmed, Rizwan E; Santhanam, Gopal; Shenoy, Krishna V; Meng, Teresa H

2004-01-01

A new class of neural prosthetic systems aims to assist disabled patients by translating cortical neural activity into control signals for prosthetic devices. Based on the success of proof-of-concept systems in the laboratory, there is now considerable interest in increasing system performance and creating implantable electronics for use in clinical systems. A critical question that impacts system performance and the overall architecture of these systems is whether it is possible to identify the neural source of each action potential (spike sorting) in real-time and with low power. Low power is essential both for power supply considerations and heat dissipation in the brain. In this paper we report that several state-of-the-art spike sorting algorithms implemented in modern CMOS VLSI processes are expected to be power realistic.

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

PubMed

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.

Representing high-dimensional data to intelligent prostheses and other wearable assistive robots: A first comparison of tile coding and selective Kanerva coding.

PubMed

Travnik, Jaden B; Pilarski, Patrick M

2017-07-01

Prosthetic devices have advanced in their capabilities and in the number and type of sensors included in their design. As the space of sensorimotor data available to a conventional or machine learning prosthetic control system increases in dimensionality and complexity, it becomes increasingly important that this data be represented in a useful and computationally efficient way. Well structured sensory data allows prosthetic control systems to make informed, appropriate control decisions. In this study, we explore the impact that increased sensorimotor information has on current machine learning prosthetic control approaches. Specifically, we examine the effect that high-dimensional sensory data has on the computation time and prediction performance of a true-online temporal-difference learning prediction method as embedded within a resource-limited upper-limb prosthesis control system. We present results comparing tile coding, the dominant linear representation for real-time prosthetic machine learning, with a newly proposed modification to Kanerva coding that we call selective Kanerva coding. In addition to showing promising results for selective Kanerva coding, our results confirm potential limitations to tile coding as the number of sensory input dimensions increases. To our knowledge, this study is the first to explicitly examine representations for realtime machine learning prosthetic devices in general terms. This work therefore provides an important step towards forming an efficient prosthesis-eye view of the world, wherein prompt and accurate representations of high-dimensional data may be provided to machine learning control systems within artificial limbs and other assistive rehabilitation technologies.

The current status of fluoroscopy and echocardiography in the diagnosis of prosthetic valve thrombosis-a review article.

PubMed

Gürsoy, Mustafa Ozan; Kalçik, Macit; Karakoyun, Süleyman; Özkan, Mehmet

2015-01-01

Prosthetic valve thrombosis (PVT) is a potentially life-threatening complication of heart valve replacement. Early diagnosis is crucial for the prevention of significantly morbid and lethal complications. Cinefluoroscopy (CF) and echocardiography have been widely used for diagnosing PVT. In recent years, the role of CF has declined since the introduction of transesophageal echocardiography and the great improvements in ultrasound technology including real time three-dimensional imaging. Nevertheless, both echocardiography and CF provide different kinds of information on prosthesis function, and therefore they are considered as complementary and not alternative. In this review, we aimed to summarize the current status of CF and echocardiography in the diagnosis of PVT. © 2014, Wiley Periodicals, Inc.

Development of a Prototype Over-Actuated Biomimetic Prosthetic Hand

PubMed Central

Williams, Matthew R.; Walter, Wayne

2015-01-01

The loss of a hand can greatly affect quality of life. A prosthetic device that can mimic normal hand function is very important to physical and mental recuperation after hand amputation, but the currently available prosthetics do not fully meet the needs of the amputee community. Most prosthetic hands are not dexterous enough to grasp a variety of shaped objects, and those that are tend to be heavy, leading to discomfort while wearing the device. In order to attempt to better simulate human hand function, a dexterous hand was developed that uses an over-actuated mechanism to form grasp shape using intrinsic joint mounted motors in addition to a finger tendon to produce large flexion force for a tight grip. This novel actuation method allows the hand to use small actuators for grip shape formation, and the tendon to produce high grip strength. The hand was capable of producing fingertip flexion force suitable for most activities of daily living. In addition, it was able to produce a range of grasp shapes with natural, independent finger motion, and appearance similar to that of a human hand. The hand also had a mass distribution more similar to a natural forearm and hand compared to contemporary prosthetics due to the more proximal location of the heavier components of the system. This paper describes the design of the hand and controller, as well as the test results. PMID:25790306

Is There an Association Between Smoking Status and Prosthetic Joint Infection After Primary Total Joint Arthroplasty?

PubMed

Gonzalez, Amanda I; Luime, Jolanda J; Uçkay, Ilker; Hannouche, Didier; Hoffmeyer, Pierre; Lübbeke, Anne

2018-02-23

Recent reports highlighted the association between smoking and higher risk of postsurgical infections. The aim was to compare the incidence of prosthetic joint infection after primary total joint arthroplasty (TJA) according to smoking status. A prospective hospital registry-based cohort study was performed including all primary knee and hip TJAs performed between March 1996 and December 2013. Smoking status preoperatively was classified into never, former, and current smoker. Incidence rates and hazard ratios (HRs) for prosthetic joint infection according to smoking status were assessed within the first year and beyond. We included 8559 primary TJAs (mean age 69.5 years), and median follow-up was 67 months. There were 5722 never, 1315 former, and 1522 current smokers. Incidence rates of infection within the first year for never, former, and current smokers were, respectively, 4.7, 10.1, and 10.9 cases/1000 person-years, comparing ever vs never smokers, crude and adjusted HRs were 2.35 (95% confidence interval [CI] 1.39-3.98) and 1.8 (95% CI 1.04-3.2). Beyond the first year, crude and adjusted HRs were 1.37 (95% CI 0.78-2.39) and 1.12 (95% CI 0.61-2.04). Smoking increased the infection risk about 1.8 times after primary hip or knee TJA in both current and former smokers. Beyond the first year, the infection risk was similar to never smokers. Copyright © 2018 Elsevier Inc. All rights reserved.

Assessment of dental prosthetic status and needs among prisoners of haryana, India.

PubMed

Bansal, Vikram; Veeresha, K L; Sogi, G M; Kumar, Adarsh; Bansal, Shelly

2013-09-01

This cross-sectional study was planned to evaluate the prosthetic status and treatment needs using WHO (1997) format among prisoners of Haryana state, India. 1,393 subjects with age range of 35.26 ± 12.29 years were examined. Of the study subjects, 11 (0.8 %) were completely while 606 (43.5 %) were partially edentulous. Of these 617 subjects, 305 (49.4 %) were edentulous only in posterior region. Dental caries accounted for loss of teeth in 325 (52.7 %) subjects. 44 (7.1 %) subjects were wearing some prosthesis. Regarding dental arch wise prosthetic need, 335 (54.3 %) subjects needed prosthesis in maxillary arch while 482 (78.1 %) needed prosthesis in mandibular arch. With advancing age there was an increase in the number of complete dental prosthesis required. There was no statistically significant difference between length of imprisonment and prosthetic need, except for need of a combination of prosthesis. Only one-fourth of the prisons had a dentist. The prisoners were taken to a hospital outside the prison in case of health needs. Prosthetic needs of prisoners were high. The lack of dental infrastructure in prisons makes the provision for multi-visit conservative dental treatments very difficult leading to higher tooth mortality. People who migrate back and forth across the prisons and communities represent a public health opportunity that should be addressed.

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

PubMed

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 probably under-dosed for the treatment of implant and biofilm associated infections.

Prosthetic Device Infections.

PubMed

Martinez, Raquel M; Bowen, Thomas R; Foltzer, Michael A

2016-08-01

The immunocompromised host is a particularly vulnerable population in whom routine and unusual infections can easily and frequently occur. Prosthetic devices are commonly used in these patients and the infections associated with those devices present a number of challenges for both the microbiologist and the clinician. Biofilms play a major role in device-related infections, which may contribute to failed attempts to recover organisms from routine culture methods. Moreover, device-related microorganisms can be difficult to eradicate by antibiotic therapy alone. Changes in clinical practice and advances in laboratory diagnostics have provided significant improvements in the detection and accurate diagnosis of device-related infections. Disruption of the bacterial biofilm plays an essential role in recovering the causative agent in culture. Various culture and nucleic acid amplification techniques are more accurate to guide directed treatment regimens. This chapter reviews the performance characteristics of currently available diagnostic assays and summarizes published guidelines, where available, for addressing suspected infected prosthetic devices.

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

NASA Technical Reports Server (NTRS)

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 subjects. This data is available to anyone doing myoelectric control research. Its availability is an important contribution to the prosthetics research community, as many researchers do not have access to amputee subjects. Since we collected myoelectric data from subjects' sound arms as well as their residual arms, this database will also prove useful to virtual reality and robotics researchers who want to explore myoelectric-based interfaces between any user and a machine. Currently, one small company (Intelligenta, Inc.) and one university (University of New Brunswick, Canada) are using this myoelectric database under other funding to develop multifunction control systems for prostheses. A prosthetics manufacturer (Liberty Technology, Inc.) is making plans to incorporate the results of their work into an artificial hand capable of several different movements to provide functionality only dreamed of by current myoelectric users. Methods Six adults and four children, all with unilateral, below-elbow amputations served as subjects. Five of the adults (3 male, 2 female, average age 34 years) had amputations due to traumatic injury, while one adult (female, age 32 years) and the four children (3 male, 1 female, average age 13 years) had congenital (i.e. from birth) limb deficiencies.

Performance of Optimized Prosthetic Ankle Designs That Are Based on a Hydraulic Variable Displacement Actuator (VDA).

PubMed

Gardiner, James; Bari, Abu Zeeshan; Kenney, Laurence; Twiste, Martin; Moser, David; Zahedi, Saeed; Howard, David

2017-12-01

Current energy storage and return prosthetic feet only marginally reduce the cost of amputee locomotion compared with basic solid ankle cushioned heel feet, possibly due to their lack of push-off at the end of stance. To the best of our knowledge, a prosthetic ankle that utilizes a hydraulic variable displacement actuator (VDA) to improve push-off performance has not previously been proposed. Therefore, here we report a design optimization and simulation feasibility study for a VDA-based prosthetic ankle. The proposed device stores the eccentric ankle work done from heel strike to maximum dorsiflexion in a hydraulic accumulator and then returns the stored energy to power push-off. Optimization was used to establish the best spring characteristic and gear ratio between ankle and VDA. The corresponding simulations show that, in level walking, normal push-off is achieved and, per gait cycle, the energy stored in the accumulator increases by 22% of the requirements for normal push-off. Although the results are promising, there are many unanswered questions and, for this approach to be a success, a new miniature, low-losses, and lightweight VDA would be required that is half the size of the smallest commercially available device.

A smartphone photogrammetry method for digitizing prosthetic socket interiors.

PubMed

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.

Five years follow-up of implant-prosthetic rehabilitation on a patient after mandibular ameloblastoma removal and ridge reconstruction by fibula graft and bone distraction

PubMed Central

Oteri, Giacomo; Ponte, Francesco Saverio De; Pisano, Michele; Cicciù, Marco

2012-01-01

This case report presents a combination of surgical and prosthetic solutions applied to a case of oral implant rehabilitation in post-oncologic reconstructed mandible. Bone resection due to surgical treatment of large mandibular neoplasm can cause long-span defects. Currently, mandibular fibula free flap graft is widely considered as a reliable technique for restoring this kind of defect. It restores the continuity of removed segment and re-establishes the contour of the lower jaw. However, the limited height of grafted fibula does not allow the insertion of regular length implants, therefore favouring vertical distraction osteogenesis as an important treatment choice. This report presents a patient affected by extensive mandibular ameloblastoma who underwent surgical reconstruction by fibula free flap because of partial mandibular resection. Guided distraction osteoneogenesis technique was applied to grafted bone, in order to obtain adequate bone height and to realize a prosthetically guided placement of 8 fixtures. After osseointegration, the patient was rehabilitated with a full arch, screw-retained prosthetic restoration. At five-years follow up, excellent integration of grafted tissue, steady levels of bone around the fixtures and healthy peri-implant tissues were reported. PMID:22623943

Update on Bioengineering.

ERIC Educational Resources Information Center

Basta, Nicholas

1986-01-01

Discusses the human, plant and animal, and industrial dimensions of biotechnology, focusing on current uses in such fields as: (1) genetics; (2) electronics; (3) prosthetics; (4) drugs; (5) agriculture; and (6) the environment. (JN)

Simulated Prosthetic Vision: The Benefits of Computer-Based Object Recognition and Localization.

PubMed

Macé, Marc J-M; Guivarch, Valérian; Denis, Grégoire; Jouffrais, Christophe

2015-07-01

Clinical trials with blind patients implanted with a visual neuroprosthesis showed that even the simplest tasks were difficult to perform with the limited vision restored with current implants. Simulated prosthetic vision (SPV) is a powerful tool to investigate the putative functions of the upcoming generations of visual neuroprostheses. Recent studies based on SPV showed that several generations of implants will be required before usable vision is restored. However, none of these studies relied on advanced image processing. High-level image processing could significantly reduce the amount of information required to perform visual tasks and help restore visuomotor behaviors, even with current low-resolution implants. In this study, we simulated a prosthetic vision device based on object localization in the scene. We evaluated the usability of this device for object recognition, localization, and reaching. We showed that a very low number of electrodes (e.g., nine) are sufficient to restore visually guided reaching movements with fair timing (10 s) and high accuracy. In addition, performance, both in terms of accuracy and speed, was comparable with 9 and 100 electrodes. Extraction of high level information (object recognition and localization) from video images could drastically enhance the usability of current visual neuroprosthesis. We suggest that this method-that is, localization of targets of interest in the scene-may restore various visuomotor behaviors. This method could prove functional on current low-resolution implants. The main limitation resides in the reliability of the vision algorithms, which are improving rapidly. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

76 FR 9646 - Copayments for Medications After June 30, 2010

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-22

...; 64.008, Veterans Domiciliary Care; 64.009, Veterans Medical Care Benefits; 64.010, Veterans Nursing... Prosthetic Appliances; 64.014, Veterans State Domiciliary Care; 64.015, Veterans State Nursing Home Care; 64...; Medical research; Mental health programs; Nursing homes; Philippines, Reporting and recordkeeping...

Identifying the values and preferences of prosthetic users: a case study series using the repertory grid technique.

PubMed

Schaffalitzky, Elisabeth; NiMhurchadha, Sinead; Gallagher, Pamela; Hofkamp, Susan; MacLachlan, Malcolm; Wegener, Stephen T

2009-06-01

The matching of prosthetic devices to the needs of the individual is a challenge for providers and patients. The aims of this study are to explore the values and preferences that prosthetic users have of their prosthetic devices; to investigate users' perceptions of alternative prosthetic options and to demonstrate a novel method for exploring the values and preferences of prosthetic users. This study describes four case studies of upper limb and lower limb high tech and conventional prosthetic users. Participants were interviewed using the repertory grid technique (RGT), a qualitative technique to explore individual values and preferences regarding specific choices and events. The participants generated distinctive patterns of personal constructs and ratings regarding prosthetic use and different prosthetic options available. The RGT produced a unique profile of preferences regarding prosthetic technologies for each participant. User choice is an important factor when matching prosthetic technology to the user. The consumer's values regarding different prosthetic options are likely to be a critical factor in prosthetic acceptance and ultimate quality of life. The RGT offers a structured method of exploring these attitudes and values without imposing researcher or practitioner bias and identifies personalized dimensions for providers and users to evaluate the individuals' preferences in prosthetic technology.

Flow in prosthetic heart valves: state-of-the-art and future directions.

PubMed

Yoganathan, Ajit P; Chandran, K B; Sotiropoulos, Fotis

2005-12-01

Since the first successful implantation of a prosthetic heart valve four decades ago, over 50 different designs have been developed including both mechanical and bioprosthetic valves. Today, the most widely implanted design is the mechanical bileaflet, with over 170,000 implants worldwide each year. Several different mechanical valves are currently available and many of them have good bulk forward flow hemodynamics, with lower transvalvular pressure drops, larger effective orifice areas, and fewer regions of forward flow stasis than their earlier-generation counterparts such as the ball-and-cage and tilting-disc valves. However, mechanical valve implants suffer from complications resulting from thrombus deposition and patients implanted with these valves need to be under long-term anti-coagulant therapy. In general, blood thinners are not needed with bioprosthetic implants, but tissue valves suffer from structural failure with, an average life-time of 10-12 years, before replacement is needed. Flow-induced stresses on the formed elements in blood have been implicated in thrombus initiation within the mechanical valve prostheses. Regions of stress concentration on the leaflets during the complex motion of the leaflets have been implicated with structural failure of the leaflets with bioprosthetic valves. In vivo and in vitro experimental studies have yielded valuable information on the relationship between hemodynamic stresses and the problems associated with the implants. More recently, Computational Fluid Dynamics (CFD) has emerged as a promising tool, which, alongside experimentation, can yield insights of unprecedented detail into the hemodynamics of prosthetic heart valves. For CFD to realize its full potential, however, it must rely on numerical techniques that can handle the enormous geometrical complexities of prosthetic devices with spatial and temporal resolution sufficiently high to accurately capture all hemodynamically relevant scales of motion. Such algorithms do not exist today and their development should be a major research priority. For CFD to further gain the confidence of valve designers and medical practitioners it must also undergo comprehensive validation with experimental data. Such validation requires the use of high-resolution flow measuring tools and techniques and the integration of experimental studies with CFD modeling.

OCT-based profiler for automating ocular surface prosthetic fitting (Conference Presentation)

NASA Astrophysics Data System (ADS)

Mujat, Mircea; Patel, Ankit H.; Maguluri, Gopi N.; Iftimia, Nicusor V.; Patel, Chirag; Agranat, Josh; Tomashevskaya, Olga; Bonte, Eugene; Ferguson, R. Daniel

2016-03-01

The use of a Prosthetic Replacement of the Ocular Surface Environment (PROSE) device is a revolutionary treatment for military patients that have lost their eyelids due to 3rd degree facial burns and for civilians who suffer from a host of corneal diseases. However, custom manual fitting is often a protracted painful, inexact process that requires multiple fitting sessions. Training for new practitioners is a long process. Automated methods to measure the complete corneal and scleral topology would provide a valuable tool for both clinicians and PROSE device manufacturers and would help streamline the fitting process. PSI has developed an ocular anterior-segment profiler based on Optical Coherence Tomography (OCT), which provides a 3D measure of the surface of the sclera and cornea. This device will provide topography data that will be used to expedite and improve the fabrication process for PROSE devices. OCT has been used to image portions of the cornea and sclera and to measure surface topology for smaller contact lenses [1-3]. However, current state-of-the-art anterior eye OCT systems can only scan about 16 mm of the eye's anterior surface, which is not sufficient for covering the sclera around the cornea. In addition, there is no systematic method for scanning and aligning/stitching the full scleral/corneal surface and commercial segmentation software is not optimized for the PROSE application. Although preliminary, our results demonstrate the capability of PSI's approach to generate accurate surface plots over relatively large areas of the eye, which is not currently possible with any other existing platform. Testing the technology on human volunteers is currently underway at Boston Foundation for Sight.

42 CFR 440.120 - Prescribed drugs, dentures, prosthetic devices, and eyeglasses.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Federal and State law; (2) Dispensed by licensed pharmacists and licensed authorized practitioners in accordance with the State Medical Practice Act; and (3) Dispensed by the licensed pharmacist or practitioner on a written prescription that is recorded and maintained in the pharmacist's or practitioner's...

42 CFR 440.120 - Prescribed drugs, dentures, prosthetic devices, and eyeglasses.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Federal and State law; (2) Dispensed by licensed pharmacists and licensed authorized practitioners in accordance with the State Medical Practice Act; and (3) Dispensed by the licensed pharmacist or practitioner on a written prescription that is recorded and maintained in the pharmacist's or practitioner's...

42 CFR 440.120 - Prescribed drugs, dentures, prosthetic devices, and eyeglasses.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Federal and State law; (2) Dispensed by licensed pharmacists and licensed authorized practitioners in accordance with the State Medical Practice Act; and (3) Dispensed by the licensed pharmacist or practitioner on a written prescription that is recorded and maintained in the pharmacist's or practitioner's...

42 CFR 440.120 - Prescribed drugs, dentures, prosthetic devices, and eyeglasses.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Federal and State law; (2) Dispensed by licensed pharmacists and licensed authorized practitioners in accordance with the State Medical Practice Act; and (3) Dispensed by the licensed pharmacist or practitioner on a written prescription that is recorded and maintained in the pharmacist's or practitioner's...

42 CFR 440.120 - Prescribed drugs, dentures, prosthetic devices, and eyeglasses.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Federal and State law; (2) Dispensed by licensed pharmacists and licensed authorized practitioners in accordance with the State Medical Practice Act; and (3) Dispensed by the licensed pharmacist or practitioner on a written prescription that is recorded and maintained in the pharmacist's or practitioner's...

Possible sources of neuroprotection following subretinal silicon chip implantation in RCS rats

NASA Astrophysics Data System (ADS)

Pardue, Machelle T.; Phillips, Michael J.; Yin, Hang; Fernandes, Alcides; Cheng, Yian; Chow, Alan Y.; Ball, Sherry L.

2005-03-01

Current retinal prosthetics are designed to stimulate existing neural circuits in diseased retinas to create a visual signal. However, implantation of retinal prosthetics may create a neurotrophic environment that also leads to improvements in visual function. Possible sources of increased neuroprotective effects on the retina may arise from electrical activity generated by the prosthetic, mechanical injury due to surgical implantation, and/or presence of a chronic foreign body. This study evaluates these three neuroprotective sources by implanting Royal College of Surgeons (RCS) rats, a model of retinitis pigmentosa, with a subretinal implant at an early stage of photoreceptor degeneration. Treatment groups included rats implanted with active and inactive devices, as well as sham-operated. These groups were compared to unoperated controls. Evaluation of retinal function throughout an 18 week post-implantation period demonstrated transient functional improvements in eyes implanted with an inactive device at 6, 12 and 14 weeks post-implantation. However, the number of photoreceptors located directly over or around the implant or sham incision was significantly increased in eyes implanted with an active or inactive device or sham-operated. These results indicate that in the RCS rat localized neuroprotection of photoreceptors from mechanical injury or a chronic foreign body may provide similar results to subretinal electrical stimulation at the current output evaluated here.

Mechanical resistance of zirconium implant abutments: A review of the literature

PubMed Central

Vaquero-Aguilar, Cristina; Torres-Lagares, Daniel; Jiménez-Melendo, Manuel; Gutiérrez-Pérez, José L.

2012-01-01

The increase of aesthetic demands, together with the successful outcome of current implants, has renewed interest in the search for new materials with enough mechanical properties and better aesthetic qualities than the materials customarily used in implanto-prosthetic rehabilitation. Among these materials, zirconium has been used in different types of implants, including prosthetic abutments. The aim of the present review is to analyse current scientific evidence supporting the use of this material for the above mentioned purposes. We carried out the review of the literature published in the last ten years (2000 through 2010) of in vitro trials of dynamic and static loading of zirconium abutments found in the databases of Medline and Cochrane using the key words zirconium abutment, fracture resistance, fracture strength, cyclic loading. Although we have found a wide variability of values among the different studies, abutments show favourable clinical behaviour for the rehabilitation of single implants in the anterior area. Such variability may be explained by the difficulty to simulate daily mastication under in vitro conditions. The clinical evidence, as found in our study, does not recommend the use of implanto-prosthetic zirconium abutments in the molar area. Key words: Zirconium abutment, zirconium implant abutment, zirconia abutment, fracture resistance, fracture strength, cyclic loading. PMID:22143702

Clinically Relevant Outcome Measures Following Limb Osseointegration; Systematic Review of the Literature.

PubMed

Al Muderis, Munjed M; Lu, William Y; Li, Jiao Jiao; Kaufman, Kenton; Orendurff, Michael; Highsmith, M Jason; Lunseth, Paul A; Kahle, Jason T

2018-02-01

The current standard of care for an amputee is a socket-based prostheses. An osseointegrated implant (OI) is an alternative for prosthetic attachment. Osseointegration addresses reported problems related to wearing a socket interface, such as skin issues, discomfort, diminished function, quality of life, prosthetic use, and abandonment. The purpose of this report is to systematically review current literature regarding OI to identify and categorize the reported clinically relevant outcome measures, rate the quality of available evidence, and synthesize the findings. A multidisciplinary team used PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methods. Search methodology was based on identifying clinically relevant articles. Three databases were searched: PubMed, CINAHL, and Web of Science. Clinical studies with aggregated data reporting at least 1 clinically relevant outcome measure were included. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criterion was used for critical appraisal and recommendations. This review identified 21 clinically relevant observational studies. Outcome measures were categorized into the following 9 categories: vibratory stimulation, complications, biomechanics, economics, patient-reported outcome measures, electromyography, x-ray, physical functional performance, and energy consumption. This systematic review consisted of Level III and IV observational studies. Homogeneous outcome measures with strong psychometric properties across prospective studies do not exist to date. Higher-level, prospective, randomized, long-term, clinically relevant trials are needed to prove efficacy of OI compared with socket prosthetic attachment. Osseointegration was at least equivalent to sockets in most studies. In some cases, it was superior. Osseointegration represents a promising alternative to socket prosthetic attachments for extremity amputees. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

A Multi-Class Proportional Myocontrol Algorithm for Upper Limb Prosthesis Control: Validation in Real-Life Scenarios on Amputees.

PubMed

Amsuess, Sebastian; Goebel, Peter; Graimann, Bernhard; Farina, Dario

2015-09-01

Functional replacement of upper limbs by means of dexterous prosthetic devices remains a technological challenge. While the mechanical design of prosthetic hands has advanced rapidly, the human-machine interfacing and the control strategies needed for the activation of multiple degrees of freedom are not reliable enough for restoring hand function successfully. Machine learning methods capable of inferring the user intent from EMG signals generated by the activation of the remnant muscles are regarded as a promising solution to this problem. However, the lack of robustness of the current methods impedes their routine clinical application. In this study, we propose a novel algorithm for controlling multiple degrees of freedom sequentially, inherently proportionally and with high robustness, allowing a good level of prosthetic hand function. The control algorithm is based on the spatial linear combinations of amplitude-related EMG signal features. The weighting coefficients in this combination are derived from the optimization criterion of the common spatial patterns filters which allow for maximal discriminability between movements. An important component of the study is the validation of the method which was performed on both able-bodied and amputee subjects who used physical prostheses with customized sockets and performed three standardized functional tests mimicking daily-life activities of varying difficulty. Moreover, the new method was compared in the same conditions with one clinical/industrial and one academic state-of-the-art method. The novel algorithm outperformed significantly the state-of-the-art techniques in both subject groups for tests that required the activation of more than one degree of freedom. Because of the evaluation in real time control on both able-bodied subjects and final users (amputees) wearing physical prostheses, the results obtained allow for the direct extrapolation of the benefits of the proposed method for the end users. In conclusion, the method proposed and validated in real-life use scenarios, allows the practical usability of multifunctional hand prostheses in an intuitive way, with significant advantages with respect to previous systems.

Analyse of socket-prosthesis-blunt complex for lower limb amputee using objective measure of patient's gait cycle.

PubMed

Rotariu, Mariana; Filep, R; Turnea, M; Ilea, M; Arotăriţei, D; Popescu, Marilena

2015-01-01

The prosthetic application is a highly complex process. Modeling and simulation of biomechanics processes in orthopedics is a certainly field of interest in current medical research. Optimization of socket in order to improve the quality of patient's life is a major objective in prosthetic rehabilitation. A variety of numerical methods for prosthetic application have been developed and studied. An objective method is proposed to evaluate the performance of a prosthetic patient according to surface pressure map over the residual limb. The friction coefficient due to various liners used in transtibial and transfemoral prosthesis is taken into account also. Creation of a bio-based modeling and mathematical simulation allows the design, construction and optimization of contact between the prosthesis cup and lack of functionality of the patient amputated considering the data collected and processed in real time and non-invasively. The von Mises stress distribution in muscle flap tissue at the bone ends shows a larger region subjected to elevated von Mises stresses in the muscle tissue underlying longer truncated bones. Finite element method was used to conduct a stress analysis and show the force distribution along the device. The results contribute to a better understanding the design of an optimized prosthesis that increase the patient's performance along with a god choice of liner, made by an appropriate material that fit better to a particular blunt. The study of prosthetic application is an exciting and important topic in research and will profit considerably from theoretical input. Interpret these results to be a permanent collaboration between math's and medical orthopedics.

Factors influencing the cost of prosthetic joint infection treatment.

PubMed

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.

Improved Diagnosis of Prosthetic Joint Infection by Culturing Periprosthetic Tissue Specimens in Blood Culture Bottles.

PubMed

Peel, Trisha N; Dylla, Brenda L; Hughes, John G; Lynch, David T; Greenwood-Quaintance, Kerryl E; Cheng, Allen C; Mandrekar, Jayawant N; Patel, Robin

2016-01-05

Despite known low sensitivity, culture of periprosthetic tissue specimens on agars and in broths is routine. Culture of periprosthetic tissue samples in blood culture bottles (BCBs) is potentially more convenient, but it has been evaluated in a limited way and has not been widely adopted. The aim of this study was to compare the sensitivity and specificity of inoculation of periprosthetic tissue specimens into blood culture bottles with standard agar and thioglycolate broth culture, applying Bayesian latent class modeling (LCM) in addition to applying the Infectious Diseases Society of America (IDSA) criteria for prosthetic joint infection. This prospective cohort study was conducted over a 9-month period (August 2013 to April 2014) at the Mayo Clinic, Rochester, MN, and included all consecutive patients undergoing revision arthroplasty. Overall, 369 subjects were studied; 117 (32%) met IDSA criteria for prosthetic joint infection, and 82% had late chronic infection. Applying LCM, inoculation of tissues into BCBs was associated with a 47% improvement in sensitivity compared to the sensitivity of conventional agar and broth cultures (92.1 versus 62.6%, respectively); this magnitude of change was similar when IDSA criteria were applied (60.7 versus 44.4%, respectively; P = 0.003). The time to microorganism detection was shorter with BCBs than with standard media (P < 0.0001), with aerobic and anaerobic BCBs yielding positive results within a median of 21 and 23 h, respectively. Results of our study demonstrate that the semiautomated method of periprosthetic tissue culture in blood culture bottles is more sensitive than and as specific as agar and thioglycolate broth cultures and yields results faster. Prosthetic joint infections are a devastating complication of arthroplasty surgery. Despite this, current microbiological techniques to detect and diagnose infections are imperfect. This study examined a new approach to diagnosing infections, through the inoculation of tissue samples from around the prosthetic joint into blood culture bottles. This study demonstrated that, compared to current laboratory practices, this new technique increased the detection of infection. These findings are important for patient care to allow timely and accurate diagnosis of infection. Copyright © 2016 Peel et al.

Unusual infections due to Listeria monocytogenes in the Southern California Desert.

PubMed

Cone, Lawrence A; Somero, Michael S; Qureshi, Farsana J; Kerkar, Shuba; Byrd, Richard G; Hirschberg, Joel M; Gauto, Anibal R

2008-11-01

During the past 22 years, 14 patients have been hospitalized with infection due to Listeria monocytogenes at the Eisenhower Medical Center, a regional 300-bed hospital in the desert southwest of Southern California. A large number of patients are retired, elderly, and have underlying and often systemic disease. Blood agar and routine media were inoculated with liquid from a sterile site such as blood, cerebrospinal fluid, or joint fluid and observed daily for growth. Appropriate biochemical studies were used to speciate the organism. While bacteremia and meningitis constitute 75% of infections in most studies, they made up only 36% of patients in the current study. Listeriosis occurred mostly in patients with infected aortic aneurysms and brain abscesses, and in prosthetic joint infections. While mortality is generally stated to be around 45% in patients with listeriosis, it was 35% in this study. However, there were no deaths in five patients with bacteremia or meningitis inferring that organ involvement poses a greater hazard for survival. Listeriosis usually presents as a bacteremia or meningitis due to a food-borne invasive infection. In the desert of Southern California most cases are seen in older patients with underlying disease and present with infected aortic aneurysms, prosthetic joints, and brain abscesses. They represent a greater threat to survival due to organ involvement.

Sensory feedback add-on for upper-limb prostheses.

PubMed

Fallahian, Nader; Saeedi, Hassan; Mokhtarinia, Hamidreza; Tabatabai Ghomshe, Farhad

2017-06-01

Sensory feedback systems have been of great interest in upper-limb prosthetics. Despite tremendous research, there are no commercial modality-matched feedback systems. This article aims to introduce the first detachable and feedback add-on option that can be attached to in-use prostheses. A sensory feedback system was tested on a below-elbow myoelectric prosthesis. The aim was to have the amputee grasp fragile objects without crushing while other accidental feedback sources were blocked. A total of 8 successful trials (out of 10) showed that sensory feedback system decreased the amputee's visual dependency by improving awareness of his prosthesis. Sensory feedback system can be used either as post-fabrication (prosthetic add-on option) or para-fabrication (incorporated into prosthetic design). The use of these direct feedback systems can be explored with a current prosthesis before ordering new high-tech prosthesis. Clinical relevance This technical note introduces the first attach/detach-able sensory feedback system that can simply be added to in-use (myo)electric prosthesis, with no obligation to change prosthesis design or components.

Quadriceps muscle injury in trans-femoral amputees.

PubMed

Alsindi, Z; Datta, D

1998-12-01

Two male trans-femoral amputees using modular trans-femoral prostheses lost control and fell to the ground when their prosthetic knees gave way. The semi-automatic knee lock malfunctioned in the first case while the free knee stabilising mechanics gave way in the second case. This resulted in a high tensile force acting on the contralateral quadriceps muscle causing it to rupture. As there are a significant number of patients with both kinds of prostheses it is important to be aware of this possibility so that necessary actions can be taken to minimise its occurrence. Even with the currently available weight activated stance phase control, the prosthetic knee will give way if the knee is flexed more than 20 degrees on weight bearing. Good power and control of hip extensors on the amputation side is needed to control the prosthetic knee joint, especially in the early stage of the walking cycle, i.e., from heel strike to mid-stance. Quadriceps muscle injury in amputees, as far as the authors are aware, has not been reported previously.

Peri‐prosthetic tissue cells show osteogenic capacity to differentiate into the osteoblastic lineage

PubMed Central

Schoeman, Monique A.E.; Oostlander, Angela E.; Rooij, Karien Ede; Valstar, Edward R.

2017-01-01

ABSTRACT During the process of aseptic loosening of prostheses, particulate wear debris induces a continuous inflammatory‐like response resulting in the formation of a layer of fibrous peri‐prosthetic tissue at the bone‐prosthesis interface. The current treatment for loosening is revision surgery which is associated with a high‐morbidity rate, especially in old patients. Therefore, less invasive alternatives are necessary. One approach could be to re‐establish osseointegration of the prosthesis by inducing osteoblast differentiation in the peri‐prosthetic tissue. Therefore, the aim of this study was to investigate the capacity of peri‐prosthetic tissue cells to differentiate into the osteoblast lineage. Cells isolated from peri‐prosthetic tissue samples (n = 22)−obtained during revision surgeries−were cultured under normal and several osteogenic culture conditions. Osteogenic differentiation was assessed by measurement of Alkaline Phosphatse (ALP), mineralization of the matrix and expression of several osteogenic genes. Cells cultured in osteogenic medium showed a significant increase in ALP staining (p = 0.024), mineralization of the matrix (p < 0.001) and ALP gene expression (p = 0.014) compared to normal culture medium. Addition of bone morphogenetic proteins (BMPs), a specific GSK3β inhibitor (GIN) or a combination of BMP and GIN to osteogenic medium could not increase ALP staining, mineralization, and ALP gene expression. In one donor, addition of GIN was required to induce mineralization of the matrix. Overall, we observed a high‐inter‐donor variability in response to osteogenic stimuli. In conclusion, peri‐prosthetic tissue cells, cultured under osteogenic conditions, can produce alkaline phosphatase and mineralized matrix, and therefore show characteristics of differentiation into the osteoblastic lineage. © 2016 The Authors. Journal of Orthopaedic Research published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society. J Orthop Res 35:1732–1742, 2017. PMID:27714894

a Review of Retinal Prosthesis Approaches

NASA Astrophysics Data System (ADS)

Kien, Tran Trung; Maul, Tomas; Bargiela, Andrzej

Age-related macular degeneration and retinitis pigmentosa are two of the most common diseases that cause degeneration in the outer retina, which can lead to several visual impairments up to blindness. Vision restoration is an important goal for which several different research approaches are currently being pursued. We are concerned with restoration via retinal prosthetic devices. Prostheses can be implemented intraocularly and extraocularly, which leads to different categories of devices. Cortical Prostheses and Optic Nerve Prostheses are examples of extraocular solutions while Epiretinal Prostheses and Subretinal Prostheses are examples of intraocular solutions. Some of the prostheses that are successfully implanted and tested in animals as well as humans can restore basic visual functions but still have limitations. This paper will give an overview of the current state of art of Retinal Prostheses and compare the advantages and limitations of each type. The purpose of this review is thus to summarize the current technologies and approaches used in developing Retinal Prostheses and therefore to lay a foundation for future designs and research directions.

Biologically inspired multi-layered synthetic skin for tactile feedback in prosthetic limbs.

PubMed

Osborn, Luke; Nguyen, Harrison; Betthauser, Joseph; Kaliki, Rahul; Thakor, Nitish

2016-08-01

The human body offers a template for many state-of-the-art prosthetic devices and sensors. In this work, we present a novel, sensorized synthetic skin that mimics the natural multi-layered nature of mechanoreceptors found in healthy glabrous skin to provide tactile information. The multi-layered sensor is made up of flexible piezoresistive textiles that act as force sensitive resistors (FSRs) to convey tactile information, which are embedded within a silicone rubber to resemble the compliant nature of human skin. The top layer of the synthetic skin is capable of detecting small loads less than 5 N whereas the bottom sensing layer responds reliably to loads over 7 N. Finite element analysis (FEA) of a simplified human fingertip and the synthetic skin was performed. Results suggest similarities in behavior during loading. A natural tactile event is simulated by loading the synthetic skin on a prosthetic limb. Results show the sensors' ability to detect applied loads as well as the ability to simulate neural spiking activity based on the derivative and temporal differences of the sensor response. During the tactile loading, the top sensing layer responded 0.24 s faster than the bottom sensing layer. A synthetic biologically-inspired skin such as this will be useful for enhancing the functionality of prosthetic limbs through tactile feedback.

21 CFR 870.3945 - Prosthetic heart valve sizer.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prosthetic heart valve sizer. 870.3945 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3945 Prosthetic heart valve sizer. (a) Identification. A prosthetic heart valve sizer is a device used to measure the size of the...

21 CFR 870.3945 - Prosthetic heart valve sizer.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Prosthetic heart valve sizer. 870.3945 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3945 Prosthetic heart valve sizer. (a) Identification. A prosthetic heart valve sizer is a device used to measure the size of the...

21 CFR 870.3945 - Prosthetic heart valve sizer.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Prosthetic heart valve sizer. 870.3945 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3945 Prosthetic heart valve sizer. (a) Identification. A prosthetic heart valve sizer is a device used to measure the size of the...

21 CFR 870.3945 - Prosthetic heart valve sizer.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Prosthetic heart valve sizer. 870.3945 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3945 Prosthetic heart valve sizer. (a) Identification. A prosthetic heart valve sizer is a device used to measure the size of the...

21 CFR 870.3945 - Prosthetic heart valve sizer.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Prosthetic heart valve sizer. 870.3945 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3945 Prosthetic heart valve sizer. (a) Identification. A prosthetic heart valve sizer is a device used to measure the size of the...

A new paradigm for obtaining marketing approval for pediatric-sized prosthetic heart valves.

PubMed

Yoganathan, Ajit P; Fogel, Mark; Gamble, Susan; Morton, Michael; Schmidt, Paul; Secunda, Jeff; Vidmar, Sara; Del Nido, Pedro

2013-10-01

Congenital heart valve disease is one of the most common abnormalities in children. There are limited technological solutions available for treating children with congenital heart valve diseases. The aim of this study is to provide the details of the consensus reached in terms of pediatric definitions, design approach, in vitro testing, and clinical trials, which may be used as guidance for developing prosthetic heart valves for the pediatric indication. In stark contrast to the various designs of adult-sized replacement valves available in the market, there are no Food and Drug Administration (FDA)-approved prosthetic heart valves available for use in the pediatric population. There is a pressing need for FDA-approved pediatric valve devices in the United States. The pediatric patient population has been typically excluded from replacement heart valve trials for several reasons. In January 2010, heart valve manufacturers and pediatric clinicians collaborated with academicians and FDA staff in a workshop to suggest ways to successfully evaluate pediatric prosthetic valves and conduct pediatric clinical trials to provide acceptable heart valve replacement options for this patient population. Recommendations, derived from ISO 5840:2005 and the 2010 FDA Draft Replacement Heart Valve Guidance, are provided for hydrodynamic, durability, and fatigue testing. The article specifically addresses in vitro and premarket and postmarket approval clinical studies that should be considered by a heart valve manufacturer for obtaining regulatory approval of pediatric sizes of prosthetic heart valve designs that are already approved for adult clinical use. Copyright © 2013 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

International Brainstorming Meeting on Etiologic and Risk Factors of Peri-implantitis, Montegrotto (Padua, Italy), August 2014.

PubMed

Canullo, Luigi; Schlee, Markus; Wagner, Wilfried; Covani, Ugo

2015-01-01

The emerging literature has recently reported an alarming increase in peri-implantitis. This disease is typically described as the result of an imbalance between host response and bacterial load, supported by gram-negative anaerobic microflora. The current literature on the prevention and treatment of peri-implantitis does not allow for the extraction of applicable clinical information. In fact, the lack of efficacy of the current treatment methods may be a result of insufficient understanding of the biology. The aim of this position paper was to try to reevaluate the etiopathogenesis of peri-implantitis, highlighting the principal clinically induced triggering factors of the disease. The consensus conference provided strong evidence to suggest that a different microbiologic flora (slightly different from that collected around teeth affected by periodontitis) could support peri-implantitis. However, the evidence to support a consensus statement regarding clinically triggering factors (surgical, prosthetic, and biomechanical) for peri-implantitis is only of moderate strength (cohort studies or consistent results from long-term, well-populated case series). Expert opinion led the consensus group to support the following: rectifying the number of peri-implant inflammatory situations caused by surgical, restorative, or material complications may lower the number of infections to a more realistic figure and may suggest different and more appropriate treatment plans. At the same time, it can be stated that implant material, shape and surface characteristics, procedures and biomaterials used for bone augmentation, and incorrect prosthetic procedures and biomechanical plans could also be risk factors for the occurrence and progression of periimplantitis.

Medical Applications for 3D Printing: Current and Projected Uses.

PubMed

Ventola, C Lee

2014-10-01

3D printing is expected to revolutionize health care through uses in tissue and organ fabrication; creation of customized prosthetics, implants, and anatomical models; and pharmaceutical research regarding drug dosage forms, delivery, and discovery.

Parastomal hernia – current knowledge and treatment

PubMed Central

Styliński, Roman; Rudzki, Sławomir

2018-01-01

Intestinal stoma creation is one of the most common surgical procedures. The most common long-term complication following stoma creation is parastomal hernia, which according to some authors is practically unavoidable. Statistical differences of its occurrence are mainly due to patient observation time and evaluation criteria. Consequently, primary prevention methods such as placement of prosthetic mesh and newly developed minimally invasive methods of stoma creation are used. It seems that in the light of evidence-based medicine, the best way to treat parastomal hernia is the one that the surgeon undertaking therapy is the most experienced in and is suited to the individuality of each patient, his condition and comorbidities. As a general rule, reinforcing the abdominal wall with a prosthetic mesh is the treatment of choice, with a low rate of complications and relapses over a long period of time. The current trend is to use lightweight, large pore meshes. PMID:29643952

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

NASA Astrophysics Data System (ADS)

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 waveguides for strain sensing in a soft prosthetic hand. These optoelectronic strain sensors are easy to fabricate, chemically inert, and demonstrate low hysteresis and high precision in their output signals. I use the optoelectronically innervated prosthetic hand to conduct various active sensation experiments inspired by the capabilities of a real hand.

Evidence that a formyl-substituted iron porphyrin is the prosthetic group of myeloperoxidase: magnetic circular dichroism similarity of the peroxidase to Spirographis heme-reconstituted myoglobin.

PubMed Central

Sono, M; Bracete, A M; Huff, A M; Ikeda-Saito, M; Dawson, J H

1991-01-01

To probe the identity of the active site heme-type prosthetic group of myeloperoxidase, whose structure has not been established unambiguously [proposed structures are (i) a chlorin (dihydroporphyrin) or (ii) a formyl-substituted porphyrin such as present in heme a], Spirographis heme (2-formyl-4-vinyldeuteroheme IX) has been incorporated into apo-myoglobin as a possible iron porphyrin model. Comparison of parallel derivatives of these two green proteins with magnetic circular dichroism spectroscopy reveals considerable similarities between several derivatives of these proteins, including the pyridine hemochromogen, the native ferric, ferrous-oxy, and ferrous-CO forms. In contrast, the magnetic circular dichroism spectra of available iron chlorin (octaethylchlorin) model complexes in analogous ligation and oxidation states do not show any significant spectral similarities to myeloperoxidase. This finding provides important evidence in favor of a formyl-substituted porphyrin as the structure of the prosthetic group macrocycle of myeloperoxidase. PMID:1662385

A Prosthetic Foot Emulator to Optimize Prescription of Prosthetic Feet in Veterans and Service Members with Leg Amputations

DTIC Science & Technology

2017-09-01

AWARD NUMBER: W81XWH-16-1-0569 TITLE: A Prosthetic Foot Emulator to Optimize Prescription of Prosthetic Feet in Veterans and Service Members...Headquarters Services , Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202- 4302...GRANT NUMBER A Prosthetic Foot Emulator to Optimize Prescription of Prosthetic Feet in Veterans and Service Members with Leg Amputations 5c

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.

PubMed

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.

Rothia mucilaginosa Prosthetic Device Infections: a Case of Prosthetic Valve Endocarditis

PubMed Central

Tokarczyk, Mindy J.; Jungkind, Donald; DeSimone, Joseph A.

2013-01-01

Rothia mucilaginosa is increasingly recognized as an emerging opportunistic pathogen associated with prosthetic device infections. Infective endocarditis is one of the most common clinical presentations. We report a case of R. mucilaginosa prosthetic valve endocarditis and review the literature of prosthetic device infections caused by this organism. PMID:23467598

Brain implants for substituting lost motor function: state of the art and potential impact on the lives of motor-impaired seniors.

PubMed

Ramsey, N F; Aarnoutse, E J; Vansteensel, M J

2014-01-01

Recent scientific achievements bring the concept of neural prosthetics for reinstating lost motor function closer to medical application. Current research involves severely paralyzed people under the age of 65, but implications for seniors with stroke or trauma-induced impairments are clearly on the horizon. Demographic changes will lead to a shortage of personnel to care for an increasing population of senior citizens, threatening maintenance of an acceptable level of care and urging ways for people to live longer at their home independent from personal assistance. This is particularly challenging when people suffer from disabilities such as partial paralysis after stroke or trauma, where daily personal assistance is required. For some of these people, neural prosthetics can reinstate some lost motor function and/or lost communication, thereby increasing independence and possibly quality of life. In this viewpoint article, we present the state of the art in decoding brain activity in the service of brain-computer interfacing. Although some noninvasive applications produce good results, we focus on brain implants that benefit from better quality brain signals. Fully implantable neural prostheses for home use are not available yet, but clinical trials are being prepared. More sophisticated systems are expected to follow in the years to come, with capabilities of interest for less severe paralysis. Eventually the combination of smart robotics and brain implants is expected to enable people to interact well enough with their environment to live an independent life in spite of motor disabilities. © 2014 S. Karger AG, Basel.

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

PubMed

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 is rare. Copyright © 2016 Elsevier Inc. All rights reserved.

Saturation in Phosphene Size with Increasing Current Levels Delivered to Human Visual Cortex.

PubMed

Bosking, William H; Sun, Ping; Ozker, Muge; Pei, Xiaomei; Foster, Brett L; Beauchamp, Michael S; Yoshor, Daniel

2017-07-26

Electrically stimulating early visual cortex results in a visual percept known as a phosphene. Although phosphenes can be evoked by a wide range of electrode sizes and current amplitudes, they are invariably described as small. To better understand this observation, we electrically stimulated 93 electrodes implanted in the visual cortex of 13 human subjects who reported phosphene size while stimulation current was varied. Phosphene size increased as the stimulation current was initially raised above threshold, but then rapidly reached saturation. Phosphene size also depended on the location of the stimulated site, with size increasing with distance from the foveal representation. We developed a model relating phosphene size to the amount of activated cortex and its location within the retinotopic map. First, a sigmoidal curve was used to predict the amount of activated cortex at a given current. Second, the amount of active cortex was converted to degrees of visual angle by multiplying by the inverse cortical magnification factor for that retinotopic location. This simple model accurately predicted phosphene size for a broad range of stimulation currents and cortical locations. The unexpected saturation in phosphene sizes suggests that the functional architecture of cerebral cortex may impose fundamental restrictions on the spread of artificially evoked activity and this may be an important consideration in the design of cortical prosthetic devices. SIGNIFICANCE STATEMENT Understanding the neural basis for phosphenes, the visual percepts created by electrical stimulation of visual cortex, is fundamental to the development of a visual cortical prosthetic. Our experiments in human subjects implanted with electrodes over visual cortex show that it is the activity of a large population of cells spread out across several millimeters of tissue that supports the perception of a phosphene. In addition, we describe an important feature of the production of phosphenes by electrical stimulation: phosphene size saturates at a relatively low current level. This finding implies that, with current methods, visual prosthetics will have a limited dynamic range available to control the production of spatial forms and that more advanced stimulation methods may be required. Copyright © 2017 the authors 0270-6474/17/377188-10$15.00/0.

Safe Direct Current Stimulator design for reduced power consumption and increased reliability.

PubMed

Fridman, Gene

2017-07-01

Current state of the art neural prosthetics, such as cochlear implants, spinal cord stimulators, and deep brain stimulators use implantable pulse generators (IPGs) to excite neural activity. Inhibition of neural firing is typically indirect and requires excitation of neurons that then have inhibitory projections downstream. Safe Direct Current Stimulator (SDCS) technology is designed to convert electronic pulses delivered to electrodes embedded within an implantable device to ionic direct current (iDC) at the output of the device. iDC from the device can then control neural extracellular potential with the intent of being able to not only excite, but also inhibit and sensitize neurons, thereby greatly expanding the possible applications of neuromodulation therapies and neural interface mechanisms. While the potential applications and proof of concept of this device have been the focus of previous work, the published descriptions of this technology leave significant room for power and reliability optimization. We describe and model a novel device construction designed to reduce power consumption by a factor of 12 and to improve its reliability by a factor of 8.

International normalized ratio self-management lowers the risk of thromboembolic events after prosthetic heart valve replacement.

PubMed

Eitz, Thomas; Schenk, Soren; Fritzsche, Dirk; Bairaktaris, Andreas; Wagner, Otto; Koertke, Heinrich; Koerfer, Reiner

2008-03-01

Although prosthetic valves are durable and easy to implant, the need for lifetime warfarin-based anticoagulation restricts their exclusive usage. We investigated if anticoagulation self-management improves outcome in a single-center series. Between 1994 and 1998, 765 patients with prosthetic valve replacements were prospectively enrolled and randomized to receive conventional anticoagulation management by their primary physician (group 1, n = 295) or to pursue anticoagulation self-management (group 2, n = 470). A study head office was implemented to coordinate and monitor anticoagulation protocols, international normalized ratios (INR), and adverse events. Patients were instructed on how to obtain and test their own blood samples and to adjust warfarin dosages according to the measured INR (target range, 2.5 to 4). Mean INR values were slightly yet significantly smaller in group 1 than in group 2 (2.8 +/- 0.7 vs 3.0 +/- .6, p < 0.001). Moreover, INR values of patients with conventional INR management were frequently measured outside the INR target range, whereas those with anticoagulation self-management mostly remained within the range (35% vs 21%, p < 0.001). In addition, the scatter of INR values was smaller if self-managed. Freedom from thromboembolism at 3, 12, and 24 months, respectively, was 99%, 95%, and 91% in group 1 compared with 99%, 98%, and 96% in group 2 (p = 0.008). Bleeding events were similar in both groups. Time-related multivariate analysis identified INR self-management and higher INR as independent predictors for better outcome. Anticoagulation self-management can improve INR profiles up to 2 years after prosthetic valve replacement and reduce adverse events. Current indications of prosthetic rather than biologic valve implantations may be extended if the benefit of INR self-management is shown by future studies with longer follow-up.

Ten-dimensional anthropomorphic arm control in a human brain-machine interface: difficulties, solutions, and limitations

NASA Astrophysics Data System (ADS)

Wodlinger, B.; Downey, J. E.; Tyler-Kabara, E. C.; Schwartz, A. B.; Boninger, M. L.; Collinger, J. L.

2015-02-01

Objective. In a previous study we demonstrated continuous translation, orientation and one-dimensional grasping control of a prosthetic limb (seven degrees of freedom) by a human subject with tetraplegia using a brain-machine interface (BMI). The current study, in the same subject, immediately followed the previous work and expanded the scope of the control signal by also extracting hand-shape commands from the two 96-channel intracortical electrode arrays implanted in the subject’s left motor cortex. Approach. Four new control signals, dictating prosthetic hand shape, replaced the one-dimensional grasping in the previous study, allowing the subject to control the prosthetic limb with ten degrees of freedom (three-dimensional (3D) translation, 3D orientation, four-dimensional hand shaping) simultaneously. Main results. Robust neural tuning to hand shaping was found, leading to ten-dimensional (10D) performance well above chance levels in all tests. Neural unit preferred directions were broadly distributed through the 10D space, with the majority of units significantly tuned to all ten dimensions, instead of being restricted to isolated domains (e.g. translation, orientation or hand shape). The addition of hand shaping emphasized object-interaction behavior. A fundamental component of BMIs is the calibration used to associate neural activity to intended movement. We found that the presence of an object during calibration enhanced successful shaping of the prosthetic hand as it closed around the object during grasping. Significance. Our results show that individual motor cortical neurons encode many parameters of movement, that object interaction is an important factor when extracting these signals, and that high-dimensional operation of prosthetic devices can be achieved with simple decoding algorithms. ClinicalTrials.gov Identifier: NCT01364480.

Real-time three-dimensional transesophageal echocardiography in valve disease: comparison with surgical findings and evaluation of prosthetic valves.

PubMed

Sugeng, Lissa; Shernan, Stanton K; Weinert, Lynn; Shook, Doug; Raman, Jai; Jeevanandam, Valluvan; DuPont, Frank; Fox, John; Mor-Avi, Victor; Lang, Roberto M

2008-12-01

Recently, a novel real-time 3-dimensional (3D) matrix-array transesophageal echocardiographic (3D-MTEE) probe was found to be highly effective in the evaluation of native mitral valves (MVs) and other intracardiac structures, including the interatrial septum and left atrial appendage. However, the ability to visualize prosthetic valves using this transducer has not been evaluated. Moreover, the diagnostic accuracy of this new technology has never been validated against surgical findings. This study was designed to (1) assess the quality of 3D-MTEE images of prosthetic valves and (2) determine the potential value of 3D-MTEE imaging in the preoperative assessment of valvular pathology by comparing images with surgical findings. Eighty-seven patients undergoing clinically indicated transesophageal echocardiography were studied. In 40 patients, 3D-MTEE images of prosthetic MVs, aortic valves (AVs), and tricuspid valves (TVs) were scored for the quality of visualization. For both MVs and AVs, mechanical and bioprosthetic valves, the rings and leaflets were scored individually. In 47 additional patients, intraoperative 3D-MTEE diagnoses of MV pathology obtained before initiating cardiopulmonary bypass were compared with surgical findings. For the visualization of prosthetic MVs and annuloplasty rings, quality was superior compared with AV and TV prostheses. In addition, 3D-MTEE imaging had 96% agreement with surgical findings. Three-dimensional matrix-array transesophageal echocardiographic imaging provides superb imaging and accurate presurgical evaluation of native MV pathology and prostheses. However, the current technology is less accurate for the clinical assessment of AVs and TVs. Fast acquisition and immediate online display will make this the modality of choice for MV surgical planning and postsurgical follow-up.

Retinal Prosthetics, Optogenetics, and Chemical Photoswitches

PubMed Central

2015-01-01

Three technologies have emerged as therapies to restore light sensing to profoundly blind patients suffering from late-stage retinal degenerations: (1) retinal prosthetics, (2) optogenetics, and (3) chemical photoswitches. Prosthetics are the most mature and the only approach in clinical practice. Prosthetic implants require complex surgical intervention and provide only limited visual resolution but can potentially restore navigational ability to many blind patients. Optogenetics uses viral delivery of type 1 opsin genes from prokaryotes or eukaryote algae to restore light responses in survivor neurons. Targeting and expression remain major problems, but are potentially soluble. Importantly, optogenetics could provide the ultimate in high-resolution vision due to the long persistence of gene expression achieved in animal models. Nevertheless, optogenetics remains challenging to implement in human eyes with large volumes, complex disease progression, and physical barriers to viral penetration. Now, a new generation of photochromic ligands or chemical photoswitches (azobenzene-quaternary ammonium derivatives) can be injected into a degenerated mouse eye and, in minutes to hours, activate light responses in neurons. These photoswitches offer the potential for rapidly and reversibly screening the vision restoration expected in an individual patient. Chemical photoswitch variants that persist in the cell membrane could make them a simple therapy of choice, with resolution and sensitivity equivalent to optogenetics approaches. A major complexity in treating retinal degenerations is retinal remodeling: pathologic network rewiring, molecular reprogramming, and cell death that compromise signaling in the surviving retina. Remodeling forces a choice between upstream and downstream targeting, each engaging different benefits and defects. Prosthetics and optogenetics can be implemented in either mode, but the use of chemical photoswitches is currently limited to downstream implementations. Even so, given the high density of human foveal ganglion cells, the ultimate chemical photoswitch treatment could deliver cost-effective, high-resolution vision for the blind. PMID:25089879

Simulation of blood flow through an artificial heart

NASA Technical Reports Server (NTRS)

Kiris, Cetin; Chang, I-Dee; Rogers, Stuart E.; Kwak, Dochan

1991-01-01

A numerical simulation of the incompressible viscous flow through a prosthetic tilting disk heart valve is presented in order to demonstrate the current capability to model unsteady flows with moving boundaries. Both steady state and unsteady flow calculations are done by solving the incompressible Navier-Stokes equations in 3-D generalized curvilinear coordinates. In order to handle the moving boundary problems, the chimera grid embedding scheme which decomposes a complex computational domain into several simple subdomains is used. An algebraic turbulence model for internal flows is incorporated to reach the physiological values of Reynolds number. Good agreement is obtained between the numerical results and experimental measurements. It is found that the tilting disk valve causes large regions of separated flow, and regions of high shear.

Comparison of Rectified and Unrectified Sockets for Transtibial Amputees.

PubMed

Engsberg, Jack R; Sprouse, S Wayne; Uhrich, Mary L; Ziegler, Barbara R; Luitjohan, F Daniel

2008-01-01

The current method for fabricating prosthetic sockets is to modify a positive mold to account for the non-homogeneity of the residual limb to tolerate load (i.e., rectified socket). We tested unrectified sockets by retaining the shape of the residual limb, except for a distal end pad, using an alginate gel process instead of casting. This investigation compared rectified and unrectified sockets. Forty-three adults with unilateral transtibial amputations were tested after randomly wearing both rectified and unrectified sockets for at least 4 weeks. Testing included a gait analysis, energy expenditure and Prosthesis Evaluation Questionnaire (PEQ). Results indicated no differences between sockets for gait speed and timing, gait kinematics and kinetics, and gait energy expenditure. There were also no differences in the Prosthetic Evaluation Questionnaire and 16 subjects selected the rectified socket, 25 selected the unrectified socket, and 2 subjects selected to use both sockets as their exit socket. Results seemed to indicate that more than one paradigm exists for shaping prosthetic sockets, and this paradigm may be helpful in understanding the mechanisms of socket fit. The alginate gel fabrication method was simpler than the traditional method. The method could be helpful in other countries where prosthetic care is lacking, may be helpful with new amputees, and may be helpful in typical clinics to reduce costs and free the prosthetist to focus more time on patient needs.

Comparison of Rectified and Unrectified Sockets for Transtibial Amputees

PubMed Central

Engsberg, Jack R.; Sprouse, S. Wayne; Uhrich, Mary L.; Ziegler, Barbara R.; Luitjohan, F. Daniel

2008-01-01

The current method for fabricating prosthetic sockets is to modify a positive mold to account for the non-homogeneity of the residual limb to tolerate load (i.e., rectified socket). We tested unrectified sockets by retaining the shape of the residual limb, except for a distal end pad, using an alginate gel process instead of casting. This investigation compared rectified and unrectified sockets. Forty-three adults with unilateral transtibial amputations were tested after randomly wearing both rectified and unrectified sockets for at least 4 weeks. Testing included a gait analysis, energy expenditure and Prosthesis Evaluation Questionnaire (PEQ). Results indicated no differences between sockets for gait speed and timing, gait kinematics and kinetics, and gait energy expenditure. There were also no differences in the Prosthetic Evaluation Questionnaire and 16 subjects selected the rectified socket, 25 selected the unrectified socket, and 2 subjects selected to use both sockets as their exit socket. Results seemed to indicate that more than one paradigm exists for shaping prosthetic sockets, and this paradigm may be helpful in understanding the mechanisms of socket fit. The alginate gel fabrication method was simpler than the traditional method. The method could be helpful in other countries where prosthetic care is lacking, may be helpful with new amputees, and may be helpful in typical clinics to reduce costs and free the prosthetist to focus more time on patient needs. PMID:18776945

Prosthetic Manhood in the Soviet Union at the End of World War II.

PubMed

Bernstein, Frances

2015-01-01

Millions of Soviet soldiers were disabled as a direct consequence of their service in the Second World War. Yet despite its expressions of gratitude for their sacrifices, the state evinced a great deal of discomfort regarding their damaged bodies. The countless armless and legless veterans were a constant reminder of the destruction suffered by the country as a whole, an association increasingly incompatible with the postwar agenda of wholesale reconstruction. This article focuses on a key strategy for erasing the scars of war, one with ostensibly unambiguous benefit for the disabled themselves: the development of prostheses. In addition to fostering independence from others and ultimately from the state, artificial limbs would facilitate the veterans' return to the kinds of socially useful labor by which the country defined itself. In so doing, this strategy engendered the establishment of a new model of masculinity: a prosthetic manhood.

On the way to total integration of prosthetic pylon with residuum

PubMed Central

Pitkin, Mark

2010-01-01

Two decades after introducing threaded titanium dental implants, Dr. Per-Ingvar Brånemark used a similar technique in the 1980s to pioneer the direct skeletal attachment (DSA) of limb prostheses. He and his colleagues used convincing clinical experience to overcome the skepticism of their peers, affording a new dimension of prosthetic rehabilitation to almost 100 individuals with amputation. As a result, more research has been initiated worldwide to move DSA to a level of greater safety, longevity, and reliability. This review highlights the trends and milestones in current DSA development. It also identifies ideas from previous studies in various fields that may be useful in future DSA development. PMID:19675987

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

PubMed Central

2011-01-01

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 436%, as compared to a configuration with a solid internal geometry. In addition, the study shows that an indentation of 2 N force on the synthetic skin with an open pocket can also achieve a displacement of more than 2 mm, while the finger phalanx from a commercially available prosthetic hand can only achieve 0.2 mm. PMID:21447188

A novel four-bar linkage prosthetic knee based on magnetorheological effect: principle, structure, simulation and control

NASA Astrophysics Data System (ADS)

Xu, Lei; Wang, Dai-Hua; Fu, Qiang; Yuan, Gang; Hu, Lei-Zi

2016-11-01

In this paper, the principle and structure of the four-bar linkage prosthetic knee based on the magnetorheological effect (FLPKME) are proposed and realized by individually integrating the upper and lower link rods of the four-bar linkage with the piston rod and the outer cylinder of the magnetorheological (MR) damper. The integrated MR damper, in which the MR fluid is operated in the shear mode, has a double-ended structure. The prototype of the FLPKME is designed and fabricated. Utilizing the developed FLPKME, the lower limb prosthesis is developed, modeled, and simulated. On these bases, the control algorithm for the FLPKME is developed. A test platform for the FLPKME is developed and the performance of the FLPKME with seven constant currents and controlled currents by the control algorithm developed in this paper are experimentally tested. The results show that the FLPKME with a constant current of 1.6 A possesses the basic stable gait, and the FLPKME with the controlled currents by the control algorithm developed in this paper is able to track the motions well and to imitate the natural motions of a healthy human knee joint.

Factors Associated with Prosthetic Looseness in Lower Limb Amputees.

PubMed

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

Threshold concepts in prosthetics.

PubMed

Hill, Sophie

2017-12-01

Curriculum documents identify key concepts within learning prosthetics. Threshold concepts provide an alternative way of viewing the curriculum, focussing on the ways of thinking and practicing within prosthetics. Threshold concepts can be described as an opening to a different way of viewing a concept. This article forms part of a larger study exploring what students and staff experience as difficult in learning about prosthetics. To explore possible threshold concepts within prosthetics. Qualitative, interpretative phenomenological analysis. Data from 18 students and 8 staff at two universities with undergraduate prosthetics and orthotics programmes were generated through interviews and questionnaires. The data were analysed using an interpretative phenomenological analysis approach. Three possible threshold concepts arose from the data: 'how we walk', 'learning to talk' and 'considering the person'. Three potential threshold concepts in prosthetics are suggested with possible implications for prosthetics education. These possible threshold concepts involve changes in both conceptual and ontological knowledge, integrating into the persona of the individual. This integration occurs through the development of memories associated with procedural concepts that combine with disciplinary concepts. Considering the prosthetics curriculum through the lens of threshold concepts enables a focus on how students learn to become prosthetists. Clinical relevance This study provides new insights into how prosthetists learn. This has implications for curriculum design in prosthetics education.

Factors influencing evidence-based practice in prosthetics and orthotics.

PubMed

Andrysek, Jan; Christensen, James; Dupuis, Annie

2011-03-01

The importance of evidence-based practice is being recognized across a broad range of healthcare disciplines as a means for improving patient outcomes and also efficiently managing healthcare resources. The objective of this work was to obtain information from clinicians about the underlying barriers and facilitators relating to evidence-based practice in prosthetics and orthotics. Cross sectional survey. An internet survey was developed and distributed to 300 prosthetists and orthotists currently practicing in Canada. A principal component factor analysis of the survey results revealed ten primary factors affecting evidence-based practice. These include time constraints, workload and system demands, limited relevant evidence from research, and gaps in skills and knowledge required to perform evidence-based practice. Clinicians value research as a means of improving clinical practice, but they are faced with a number of practical barriers in performing evidence-based practice. This study provides empirical data about the underlying barriers and facilitators relating to evidence-based practice in prosthetics and orthotics. Such data are essential in order to inform those involved in improving existing clinical practices, including educators, professional organizations, and governing bodies.

Lightweight custom composite prosthetic components using an additive manufacturing-based molding technique.

PubMed

Leddy, Michael T; Belter, Joseph T; Gemmell, Kevin D; Dollar, Aaron M

2015-01-01

Additive manufacturing techniques are becoming more prominent and cost-effective as 3D printing becomes higher quality and more inexpensive. The idea of 3D printed prosthetics components promises affordable, customizable devices, but these systems currently have major shortcomings in durability and function. In this paper, we propose a fabrication method for custom composite prostheses utilizing additive manufacturing, allowing for customizability, as well the durability of professional prosthetics. The manufacturing process is completed using 3D printed molds in a multi-stage molding system, which creates a custom finger or palm with a lightweight epoxy foam core, a durable composite outer shell, and soft urethane gripping surfaces. The composite material was compared to 3D printed and aluminum materials using a three-point bending test to compare stiffness, as well as gravimetric measurements to compare weight. The composite finger demonstrates the largest stiffness with the lowest weight compared to other tested fingers, as well as having customizability and lower cost, proving to potentially be a substantial benefit to the development of upper-limb prostheses.

A powered prosthetic ankle joint for walking and running.

PubMed

Grimmer, Martin; Holgate, Matthew; Holgate, Robert; Boehler, Alexander; Ward, Jeffrey; Hollander, Kevin; Sugar, Thomas; Seyfarth, André

2016-12-19

Current prosthetic ankle joints are designed either for walking or for running. In order to mimic the capabilities of an able-bodied, a powered prosthetic ankle for walking and running was designed. A powered system has the potential to reduce the limitations in range of motion and positive work output of passive walking and running feet. To perform the experiments a controller capable of transitions between standing, walking, and running with speed adaptations was developed. In the first case study the system was mounted on an ankle bypass in parallel with the foot of a non-amputee subject. By this method the functionality of hardware and controller was proven. The Walk-Run ankle was capable of mimicking desired torque and angle trajectories in walking and running up to 2.6 m/s. At 4 m/s running, ankle angle could be matched while ankle torque could not. Limited ankle output power resulting from a suboptimal spring stiffness value was identified as a main reason. Further studies have to show to what extent the findings can be transferred to amputees.

Robotic hand with locking mechanism using TCP muscles for applications in prosthetic hand and humanoids

NASA Astrophysics Data System (ADS)

Saharan, Lokesh; Tadesse, Yonas

2016-04-01

This paper presents a biomimetic, lightweight, 3D printed and customizable robotic hand with locking mechanism consisting of Twisted and Coiled Polymer (TCP) muscles based on nylon precursor fibers as artificial muscles. Previously, we have presented a small-sized biomimetic hand using nylon based artificial muscles and fishing line muscles as actuators. The current study focuses on an adult-sized prosthetic hand with improved design and a position/force locking system. Energy efficiency is always a matter of concern to make compact, lightweight, durable and cost effective devices. In natural human hand, if we keep holding objects for long time, we get tired because of continuous use of energy for keeping the fingers in certain positions. Similarly, in prosthetic hands we also need to provide energy continuously to artificial muscles to hold the object for a certain period of time, which is certainly not energy efficient. In this work we, describe the design of the robotic hand and locking mechanism along with the experimental results on the performance of the locking mechanism.

Nitinol for Prosthetic and Orthotic Applications

NASA Astrophysics Data System (ADS)

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.

A financial analysis of revision hip arthroplasty: the economic burden in relation to the national tariff.

PubMed

Vanhegan, I S; Malik, A K; Jayakumar, P; Ul Islam, S; Haddad, F S

2012-05-01

Revision arthroplasty of the hip is expensive owing to the increased cost of pre-operative investigations, surgical implants and instrumentation, protracted hospital stay and drugs. We compared the costs of performing this surgery for aseptic loosening, dislocation, deep infection and peri-prosthetic fracture. Clinical, demographic and economic data were obtained for 305 consecutive revision total hip replacements in 286 patients performed at a tertiary referral centre between 1999 and 2008. The mean total costs for revision surgery in aseptic cases (n = 194) were £11 897 (sd 4629), for septic revision (n = 76) £21 937 (sd 10 965), for peri-prosthetic fracture (n = 24) £18 185 (sd 9124), and for dislocation (n = 11) £10 893 (sd 5476). Surgery for deep infection and peri-prosthetic fracture was associated with longer operating times, increased blood loss and an increase in complications compared to revisions for aseptic loosening. Total inpatient stay was also significantly longer on average (p < 0.001). Financial costs vary significantly by indication, which is not reflected in current National Health Service tariffs.

Laparoscopic surgical treatment of umbilical hernia and small eventrations with prosthetic mesh using omentum overlay.

PubMed

Bratu, D; Sabău, A; Dumitra, A; Sabău, D; Miheţiu, A; Beli, L; Hulpuş, R

2014-01-01

Umbilical hernias and abdominal incisional hernias represent current pathologies which require numerous surgical alternative ways of treatment in prosthetic or non prosthetic,open or minimally invasive surgery. The method proposed by us is a less expensive option with no additional risks compared to other similar procedures as surgical technique. We conducted a retrospective study between 01.01.2008 - 01.06.2013 in which we considered a number of 23 patients with umbilical hernia and eventration, patients who received laparoscopic intraperitoneal polyester mesh covered with omentum, procedure applied at the IInd Surgery Clinic, Clinical County Emergency Hospital Sibiu. Out of 23 patients with postoperative umbilical hernia and eventration cases in which we used this surgical technique,16 were umbilical hernias and 7 post incisional hernias. The average time of surgery was 1 hour and 40 minutes, recording 4 postoperative complications remitted under conservative treatment, with a mean hospitalization of 4.1 days. Proepiploic laparoscopic treatment using omentum is a reliable alternative to a more expensive and difficult procedure involving Dual Mesh. Celsius.

AB0 blood types: impact on development of prosthetic mechanical valve thrombosis

PubMed Central

Astarcıoğlu, Mehmet Ali; Kalçık, Macit; Yesin, Mahmut; Gürsoy, Mustafa Ozan; Şen, Taner; Karakoyun, Süleyman; Gündüz, Sabahattin; Özkan, Mehmet

2016-01-01

Objective: The non-O alleles of the ABO genotype have been associated with an increased risk of thrombosis. We aimed to assess the association between blood group status and prosthetic valve thrombosis. Methods: The association between AB0 blood group status and prosthetic valve thrombosis was assessed in this retrospective study. Transesophageal echocardiography was performed in 149 patients with a diagnosis of prosthetic valve thrombosis and in 192 control subjects. Results: Non-0 blood group type (p<0.001), presence of NYHA class III-IV status (p<0.001), and central nervous system (p<0.001) and non-central nervous system (p<0.001) emboli were significantly more prevalent in prosthetic valve thrombosis patients than in the control subjects. The incidence of ineffective anticoagulation was higher in patients with prosthetic valve thrombosis than in controls (p<0.001), as was the presence of moderate to severe left atrial spontaneous echo contrast (p<0.001). The non-0 blood prosthetic valve thrombosis subgroup had a higher incidence of obstructive thrombi and central nervous system thrombotic events than having 0 blood prosthetic valve thrombosis subgroup. Non-0 blood group, ineffective anticoagulation, left atrial spontaneous echo contrast, and a poor NYHA functional capacity were identified to be the predictors of prosthetic valve thrombosis. Conclusion: Our data demonstrate that patients with non-0 compared with 0 blood groups have higher incidence of prosthetic valve thrombosis and central nervous system embolism and similar rates of non-central nervous system embolism at presentation compared with 0 blood group type. Thus, non-O blood group may be a risk factor that may be prone to the development of prosthetic valve thrombosis in patients with prosthetic heart valves. PMID:27488753

The Effect of Prosthetic Foot Push-off on Mechanical Loading Associated with Knee Osteoarthritis in Lower Extremity Amputees

PubMed Central

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.

2011-01-01

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 = −0.72 +/− 0.22; p=0.011). 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 = −0.34 +/− 0.14; 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. PMID:21803584

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

PubMed

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.

Perceived self-efficacy and specific self-reported outcomes in persons with lower-limb amputation using a non-microprocessor-controlled versus a microprocessor-controlled prosthetic knee.

PubMed

Möller, Saffran; Hagberg, Kerstin; Samulesson, Kersti; Ramstrand, Nerrolyn

2018-04-01

To measure self-efficacy in a group of individuals who have undergone a lower-limb amputation and investigate the relationship between self-efficacy and prosthetic-specific outcomes including prosthetic use, mobility, amputation-related problems and global health. A second purpose was to examine if differences exist in outcomes based upon the type of prosthetic knee unit being used. Cross-sectional study using the General Self-Efficacy (GSE) Scale and the Questionnaire for Persons with a Transfemoral Amputation (Q-TFA). Forty-two individuals participated in the study. Twenty-three used a non-microprocessor-controlled prosthetic knee joint (non-MPK) and 19 used a microprocessor-controlled prosthetic knee joint (MPK). The study sample had quite high GSE scores (32/40). GSE scores were significantly correlated to the Q-TFA prosthetic use, mobility and problem scores. High GSE scores were related to higher levels of prosthetic use, mobility, global scores and negatively related to problem score. No significant difference was observed between individuals using a non-MPK versus MPK joints. Individuals with high self-efficacy used their prosthesis to a higher degree and high self-efficacy was related to higher level of mobility, global scores and fewer problems related to the amputation in individuals who have undergone a lower-limb amputation and were using a non-MPK or MPK knee. Implications for rehabilitation Perceived self-efficacy has has been shown to be related to quality of life, prosthetic mobility and capability as well as social activities in daily life. Prosthetic rehabilitation is primary focusing on physical improvement rather than psychological interventions. More attention should be directed towards the relationship between self-efficacy and prosthetic related outcomes during prosthetic rehabilitation after a lower-limb amputation.

Full-arch implant-retained prosthetics in general dental practice.

PubMed

Rosenbaum, Nigel

2012-03-01

The loss of all teeth from one or both dental arches is a significant disability affecting self-confidence, communication, masticatory function and aesthetics. Whilst missing teeth cannot be restored to the natural state, the development of a prosthetic dentition has been a goal of dental science throughout the centuries. Contemporary techniques allow for the replacement of missing dentition with fixed or removable solutions, solving many of the problems. Implant dentistry has transformed this area of medicine. This article provides dental practitioners with an overview of this important area of patient care. Dental practitioners in clinical practice will frequently see edentulism; a good understanding of the available options for rehabilitation is essential.

Gait Characteristics When Walking on Different Slippery Walkways.

PubMed

Whitmore, Mariah W; Hargrove, Levi J; Perreault, Eric J

2016-01-01

This study sought to determine the changes in muscle activity about the ankle, knee, and hip in able-bodied people walking at steady state on surfaces with different degrees of slipperiness. Muscle activity was measured through electromyographic signals from selected lower limb muscles and quantified to directly compare changes across surface conditions. Our results showed distinct changes in the patterns of muscle activity controlling each joint. Muscles controlling the ankle showed a significant reduction in activity as the surface became more slippery, presumably resulting in a compliant distal joint to facilitate full contact with the surface. Select muscles about the knee and hip showed a significant increase in activity as the surface became more slippery. This resulted in increased knee and hip flexion likely contributing to a lowering of the body's center of mass and stabilization of the proximal leg and trunk. These findings suggest a proximal-distal gradient in the control of muscle activity that could inform the future design of adaptable prosthetic controllers. Walking on a slippery surface is extremely difficult, especially for individuals with lower limb amputations because current prostheses do not allow the compensatory changes in lower limb dynamics that occur involuntarily in unimpaired subjects. With recent advances in prosthetic control, there is the potential to provide some of these compensatory changes; however, we first need to understand how able-bodied individuals modulate their gait under these challenging conditions.

A scoping literature review of the provision of orthoses and prostheses in resource-limited environments 2000-2010. Part one: considerations for success.

PubMed

Ikeda, Andrea J; Grabowski, Alena M; Lindsley, Alida; Sadeghi-Demneh, Ebrahim; Reisinger, Kim D

2014-08-01

Literature Review We estimate that over 29 million people worldwide in resource-limited environments (RLEs) are in need of orthotic and prosthetic (O&P) devices and services. Our goal was to ascertain the current state of O&P provision in RLEs and identify factors that may lead to more successful O&P provision. We conducted a comprehensive scoping literature review of all information related to O&P provision in RLEs published from 2000 to 2010. We targeted Vietnam, Cambodia, Tanzania, Malawi, Colombia, and the Navajo Nation, but also included information about developing countries in general. We searched academic databases and grey literature. We extracted information from each article in the areas of design, manufacturing, distribution, service provision, and technology transfer. We identified commonly reported considerations and strategies for O&P provision from 431 articles. Analysis of expert consensus documents revealed recurring themes for improving O&P provision. We found that some suggestions from the consensus documents are being followed, but many are overlooked or have not yet been implemented. Areas for improvement include conducting field testing during the design process, providing services to rural environments, offering follow-up services, considering government collaboration, and encouraging an active role of the orthosis/prosthesis user. Outcomes and research studies will be further discussed in Part Two. © The International Society for Prosthetics and Orthotics 2013.

Maxillofacial prostheses challenges in resource constrained regions.

PubMed

Tetteh, Sophia; Bibb, Richard J; Martin, Simon J

2017-10-24

This study reviewed the current state of maxillofacial rehabilitation in resource-limited nations. A rigorous literature review was undertaken using several technical and clinical databases using a variety of key words pertinent to maxillofacial prosthetic rehabilitation and resource-limited areas. In addition, interviews were conducted with researchers, clinicians and prosthetists that had direct experience of volunteering or working in resource-limited countries. Results from the review and interviews suggest rehabilitating patients in resource-limited countries remains challenging and efforts to improve the situation requires a multifactorial approach. In conclusion, public health awareness programmes to reduce the causation of injuries and bespoke maxillofacial prosthetics training programmes to suit these countries, as opposed to attempting to replicate Western training programmes. It is also possible that usage of locally sourced and cheaper materials and the use of low-cost technologies could greatly improve maxillofacial rehabilitation efforts in these localities. Implications for Rehabilitation More information and support needs to be provided to maxillofacial defect/injuries patients and to their families or guardians in a culturally sensitive manner by governments. The health needs, economic and psychological needs of the patients need to be taken into account during the rehabilitation process by clinicians and healthcare organizations. The possibility of developing training programs to suit these resource limited countries and not necessarily follow conventional fabrication methods must be looked into further by educational entities.

Target of physiological gait: Realization of speed adaptive control for a prosthetic knee during swing flexion.

PubMed

Cao, Wujing; Yu, Hongliu; Zhao, Weiliang; Li, Jin; Wei, Xiaodong

2018-01-01

Prosthetic knee is the most important component of lower limb prosthesis. Speed adaptive for prosthetic knee during swing flexion is the key method to realize physiological gait. This study aims to discuss the target of physiological gait, propose a speed adaptive control method during swing flexion and research the damping adjustment law of intelligent hydraulic prosthetic knee. According to the physiological gait trials of healthy people, the control target during swing flexion is defined. A new prosthetic knee with fuzzy logical control during swing flexion is designed to realize the damping adjustment automatically. The function simulation and evaluation system of intelligent knee prosthesis is provided. Speed adaptive control test of the intelligent prosthetic knee in different velocities are researched. The maximum swing flexion of the knee angle is set between sixty degree and seventy degree as the target of physiological gait. Preliminary experimental results demonstrate that the prosthetic knee with fuzzy logical control is able to realize physiological gait under different speeds. The faster the walking, the bigger the valve closure percentage of the hydraulic prosthetic knee. The proposed fuzzy logical control strategy and intelligent hydraulic prosthetic knee are effective for the amputee to achieve physiological gait.

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

PubMed

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 metabolic rates and biomechanics of five athletes with bilateral transtibial amputations while running with different prosthetic configurations. The metabolic cost of running for these athletes is minimized by using an optimal prosthetic model and reducing prosthetic stiffness. The metabolic cost of running was independent of prosthetic height, suggesting that longer legs are not advantageous for distance running. Moreover, the in-series prosthetic stiffness governs the leg stiffness of athletes with bilateral leg amputations.

Histopathological and Immunohistochemical Evaluation of Pannus Tissue in Patients with Prosthetic Valve Dysfunction.

PubMed

Karakoyun, Süleyman; Ozan Gürsoy, Mustafa; Yesin, Mahmut; Kalçık, Macit; Astarcıoğlu, Mehmet Ali; Gündüz, Sabahattin; Emrah Oğuz, Ali; Çoban Kökten, Şermin; Nimet Karadayı, Ayşe; Tuncer, Altuğ; Köksal, Cengiz; Gökdeniz, Tayyar; Özkan, Mehmet

2016-01-01

Prosthetic valve dysfunction due to pannus formation is a rare but serious complication. Currently, limited data are available concerning the pathogenesis and immunohistochemical properties of pannus. The study aim was to investigate the morphological, histopathological and immunohistochemical characteristics of pannus formation in patients with prosthetic valve dysfunction. A total of 35 patients (10 males, 25 females; mean age 44 ± 16 years) who had undergone re-do valve surgery due to prosthetic valve obstruction was enrolled in the study. Immunohistochemical studies were aimed at evaluating the expression of alphasmooth muscle actin (α-SMA) and desmin in myofibroblasts and smooth muscle cells; epithelial membrane antigen (EMA) in epithelial cells; and CD34, Factor VIII and vascular endothelial growth factor (VEGF) in endothelial cells. Matrix metalloproteinases (MMPs) -2 and -9, and transforming growth factor-beta (TGF-β) were used to demonstrate cytokine release from macrophages, leukocytes, fibroblasts and myofibroblasts. Pannus appeared as a tough and thick tissue hyperplasia which began from outside the suture ring in the periannular region and extended to the inflow and outflow surfaces of the prosthetic valves. Histopathological analysis showed the pannus tissue to consist of chronic inflammatory cells (lymphocytes, plasma cells, macrophages and foreign body giant cells), spindle cells such as myofibroblasts, capillary blood vessels and endothelial cells laying down the lumens. Calcification was present in the pannus tissue of 19 explanted prostheses. Immunohistochemical studies revealed positive α-SMA expression in all patients, whereas 60.5% of patients were positive for desmin, 50% for EMA, 42.1% for VEGF, 39.5% for TBF-β, 42.1% for MMP-2, 86.8% for CD34, and 97.4% for Factor VIII. MMP-9 was negative in all patients. Pannus tissue appears to be formed as the result of a neointimal response in periannular regions of prosthetic valves that consist of periannular tissue migration, myofibroblast and extracellular matrix proliferation with vascular components. It is a chronic active process in which mediators such as TGF-β, VEGF and MMP-2 play roles in both matrix formation and degradation.

Vestibular ablation and a semicircular canal prosthesis affect postural stability during head turns

PubMed Central

Thompson, Lara A.; Haburcakova, Csilla; Lewis, Richard F.

2016-01-01

In our study, we examined postural stability during head turns for two rhesus monkeys: one, single animal study contrasted normal and mild bilateral vestibular ablation and a second animal study contrasted severe bilateral vestibular ablation with and without prosthetic stimulation. The monkeys freely stood, unrestrained on a balance platform and made voluntary head turns between visual targets. To quantify each animals’ posture, motions of the head and trunk, as well as torque about the body’s center-of-mass, were measured. In the mildly ablated animal, we observed less foretrunk sway in comparison to the normal state. When the canal prosthesis provided electric stimulation to the severely ablated animal, it showed a decrease in trunk sway during head turns. Because the rhesus monkey with severe bilateral vestibular loss exhibited a decrease in trunk sway when receiving vestibular prosthetic stimulation, we propose that the prosthetic electrical stimulation partially restored head velocity information. Our results provide an indication that a semicircular canal prosthesis may be an effective way to improve postural stability in patients with severe peripheral vestibular dysfunction. PMID:27405997

77 FR 14989 - Medicare Program; Revisions to the Durable Medical Equipment, Prosthetics, Orthotics, and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-14

... wheelchairs. Prosthetic devices are included in the definition of ``medical and other health services'' in section 1861(s)(8) of the Act. Prosthetic devices are defined as devices (other than dental) which replace... examples of prosthetic devices include cardiac pacemakers, cochlear implants, electrical continence aids...

75 FR 52629 - Medicare Program; Establishing Additional Medicare Durable Medical Equipment, Prosthetics...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-27

... wheelchairs. Prosthetic devices are included in the definition of ``medical and other health services'' under section 1861(s)(8) of the Act. Prosthetic devices are defined in this section of the Act as ``devices... insertion of an intraocular lens.'' Other examples of prosthetic devices include cardiac pacemakers...

Image processing strategies based on saliency segmentation for object recognition under simulated prosthetic vision.

PubMed

Li, Heng; Su, Xiaofan; Wang, Jing; Kan, Han; Han, Tingting; Zeng, Yajie; Chai, Xinyu

2018-01-01

Current retinal prostheses can only generate low-resolution visual percepts constituted of limited phosphenes which are elicited by an electrode array and with uncontrollable color and restricted grayscale. Under this visual perception, prosthetic recipients can just complete some simple visual tasks, but more complex tasks like face identification/object recognition are extremely difficult. Therefore, it is necessary to investigate and apply image processing strategies for optimizing the visual perception of the recipients. This study focuses on recognition of the object of interest employing simulated prosthetic vision. We used a saliency segmentation method based on a biologically plausible graph-based visual saliency model and a grabCut-based self-adaptive-iterative optimization framework to automatically extract foreground objects. Based on this, two image processing strategies, Addition of Separate Pixelization and Background Pixel Shrink, were further utilized to enhance the extracted foreground objects. i) The results showed by verification of psychophysical experiments that under simulated prosthetic vision, both strategies had marked advantages over Direct Pixelization in terms of recognition accuracy and efficiency. ii) We also found that recognition performance under two strategies was tied to the segmentation results and was affected positively by the paired-interrelated objects in the scene. The use of the saliency segmentation method and image processing strategies can automatically extract and enhance foreground objects, and significantly improve object recognition performance towards recipients implanted a high-density implant. Copyright © 2017 Elsevier B.V. All rights reserved.

Osseointegrated Implants and Prosthetic Reconstruction Following Skull Base Surgery.

PubMed

Hu, Shirley; Arnaoutakis, Demetri; Kadakia, Sameep; Vest, Allison; Sawhney, Raja; Ducic, Yadranko

2017-11-01

Rehabilitation following ablative skull base surgery remains a challenging task, given the complexity of the anatomical region, despite the recent advances in reconstructive surgery. Remnant defects following resection of skull base tumors are often not amenable to primary closure. As such, numerous techniques have been described for reconstruction, including local rotational muscle flaps, pedicled flaps with skin paddle, or even free tissue transfer. However, not all patients are appropriate surgical candidates and therefore may instead benefit from nonsurgical options for functional and aesthetic restoration. Osseointegrated implants and biocompatible prostheses provide a viable alternative for such a patient population. The purpose of this review serves to highlight current options for prosthetic rehabilitation of skull base defects and describe their indications, advantages, and disadvantages.

Prosthetic joint infection caused by Trueperella bernardiae.

PubMed

Gilarranz, Raul; Chamizo, Francisco; Horcajada, Iballa; Bordes-Benítez, Ana

2016-09-01

Trueperella bernardiae is a Gram-positive coryneform bacilli which role as human pathogen is unknown because it has been usually considered a contaminant. Furthermore its identification by biochemical test was difficult. We describe a prosthetic joint infection in a women who years ago underwent a total knee replacement with superinfection and necrosis of the patellar tendon as major complications. In the sample of synovial fluid collected grew a gram-positive bacilli which was identified by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) as T. bernardiae. The patient was treated with ciprofloxacin and currently preserves the prosthesis without signs of infection. Copyright © 2016 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Anaerobic prosthetic joint infection.

PubMed

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 encountered anaerobic organisms associated with PJI. Since anaerobic PJI has also been linked to dental procedures, we also reviewed information on the use of dental procedures and prophylaxis, when available. Copyright © 2015 Elsevier Ltd. All rights reserved.

Virtual Preoperative Planning and Intraoperative Navigation in Facial Prosthetic Reconstruction: A Technical Note.

PubMed

Verma, Suzanne; Gonzalez, Marianela; Schow, Sterling R; Triplett, R Gilbert

This technical protocol outlines the use of computer-assisted image-guided technology for the preoperative planning and intraoperative procedures involved in implant-retained facial prosthetic treatment. A contributing factor for a successful prosthetic restoration is accurate preoperative planning to identify prosthetically driven implant locations that maximize bone contact and enhance cosmetic outcomes. Navigational systems virtually transfer precise digital planning into the operative field for placing implants to support prosthetic restorations. In this protocol, there is no need to construct a physical, and sometimes inaccurate, surgical guide. The report addresses treatment workflow, radiologic data specifications, and special considerations in data acquisition, virtual preoperative planning, and intraoperative navigation for the prosthetic reconstruction of unilateral, bilateral, and midface defects. Utilization of this protocol for the planning and surgical placement of craniofacial bone-anchored implants allows positioning of implants to be prosthetically driven, accurate, precise, and efficient, and leads to a more predictable treatment outcome.

21 CFR 895.101 - Prosthetic hair fibers.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prosthetic hair fibers. 895.101 Section 895.101 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES BANNED DEVICES Listing of Banned Devices § 895.101 Prosthetic hair fibers. Prosthetic hair fibers are devices intended for implantation...

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

Code of Federal Regulations, 2010 CFR

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...

76 FR 18472 - Medicare Program; Revisions to the Durable Medical Equipment, Prosthetics, Orthotics, and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-04

....Prosthetic devices are included in the definition of ``medical and other health services'' under section 1861(s)(8) of the Act. Prosthetic devices are defined in this section of the Act as ``devices (other than... intraocular lens.'' Other examples of prosthetic devices include cardiac pacemakers, cochlear implants...

The effect of anti-gravity treadmill training for prosthetic rehabilitation of a case with below-knee amputation.

PubMed

Mikami, Yukio; Fukuhara, Kouki; Kawae, Toshihiro; Kimura, Hiroaki; Ochi, Mitsuo

2015-12-01

The aim of this case study was to verify the efficacy and safety of anti-gravity treadmill training for prosthetic rehabilitation following below-knee amputation. The patient underwent left below-knee amputation as a result of diabetic foot gangrene. Since his physical strength and vitality had declined during the perioperative period, anti-gravity treadmill training was introduced for his outpatient prosthetic rehabilitation. Stable prosthetic gait exercise could be carried out under guidance on the anti-gravity treadmill, quickly resulting in improved gait. Furthermore, the patient's self-efficacy and exercise tolerance were elevated after the period of anti-gravity treadmill training. At the final evaluation following 6 weeks of rehabilitation with the anti-gravity treadmill, he had acquired prosthetic gait with the assistance of a T-cane. The anti-gravity treadmill was found to be a useful instrument for prosthetic rehabilitation following below-knee amputation. Anti-gravity treadmill training has the potential to support the prosthetic rehabilitation of below-knee amputees, especially for patients whose physical strength and vitality are decreased. © The International Society for Prosthetics and Orthotics 2014.

Kinematics in the terminal swing phase of unilateral transfemoral amputees: microprocessor-controlled versus swing-phase control prosthetic knees.

PubMed

Mâaref, Khaled; Martinet, Noël; Grumillier, Constance; Ghannouchi, Slaheddine; André, Jean Marie; Paysant, Jean

2010-06-01

To analyze the spatiotemporal parameters in the terminal swing phase of the prosthetic limb in unilateral transfemoral amputees (TFAs) compared with a group of asymptomatic subjects, and to identify a latency period (LP) in the TFA between the full extension of the prosthetic knee and the initial ground contact of the ipsilateral foot. To study the correlation between the LP and the duration of the swing phase. To evaluate the influence of the type of knee, the time since amputation, and the amputation level on the latency period. Three-dimensional gait analysis with an optoelectronic device. Gait analysis laboratory of a re-education and functional rehabilitation service. TFA (n=29) and able-bodied (n=15) subjects. Not applicable. Spatiotemporal and kinematics gait parameters. The swing phase and the LP of the prosthetic limb, associated with a consequently longer single-limb stance phase in the intact limb, were significantly longer than those measured in the intact limbs of these subjects, as well as those measured on both lower limbs of the able-bodied subjects (P<.05). There is a positive correlation (P<.05; r(2)=.58 between the LP and the swing phase on the TFA's prosthetic side. The LP measured in the prosthetic limb of TFA with a swing-phase control prosthetic knee is significantly greater than in those using the microprocessor-controlled prosthetic knee (P<.05). Of negligible duration in able-bodied subjects and in the intact limb of TFA, the LP is significantly greater in the prosthetic limb. It can explain the lengthened swing phase on the prosthetic side of those subjects. The use of a microprocessor-controlled prosthetic knee allows the LP to be reduced. This LP appears to be necessary to insure the stability of the prosthetic knee. We suggest calling this time "confidence time." Copyright 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Artificial Ligaments: Promise or Panacea?

ERIC Educational Resources Information Center

Lubell, Adele

1987-01-01

The Food and Drug Administration has approved a prosthetic ligament for limited use in persons with damaged anterior cruciate ligaments (ACL). This article addresses ligament repair, ACL tears, current treatment, development of the Gore-Tex artificial ligament, other artificial ligaments in process, and arguments for and against their use.…

Advanced Prosthetic Gait Training Tool

DTIC Science & Technology

2014-10-01

AWARD NUMBER: W81XWH-10-1-0870 TITLE: Advanced Prosthetic Gait Training Tool...October 2014 2. REPORT TYPE Annual Report 3. DATES COVERED 20 Sep 2013 to 19 Sep 2014 4. TITLE AND SUBTITLE Advanced Prosthetic Gait Training...produce a computer-based Advanced Prosthetic Gait Training Tool to aid in the training of clinicians at military treatment facilities providing care

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

PubMed Central

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

2017-01-01

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. PMID:28713760

Polymeric trileaflet prosthetic heart valves: evolution and path to clinical reality

PubMed Central

Claiborne, Thomas E; Slepian, Marvin J; Hossainy, Syed; Bluestein, Danny

2013-01-01

Present prosthetic heart valves, while hemodynamically effective, remain limited by progressive structural deterioration of tissue valves or the burden of chronic anticoagulation for mechanical valves. An idealized valve prosthesis would eliminate these limitations. Polymeric heart valves (PHVs), fabricated from advanced polymeric materials, offer the potential of durability and hemocompatibility. Unfortunately, the clinical realization of PHVs to date has been hampered by findings of in vivo calcification, degradation and thrombosis. Here, the authors review the evolution of PHVs, evaluate the state of the art of this technology and propose a pathway towards clinical reality. In particular, the authors discuss the development of a novel aortic PHV that may be deployed via transcatheter implantation, as well as its optimization via device thrombogenicity emulation. PMID:23249154

Restoring the sense of touch with a prosthetic hand through a brain interface.

PubMed

Tabot, Gregg A; Dammann, John F; Berg, Joshua A; Tenore, Francesco V; Boback, Jessica L; Vogelstein, R Jacob; Bensmaia, Sliman J

2013-11-05

Our ability to manipulate objects dexterously relies fundamentally on sensory signals originating from the hand. To restore motor function with upper-limb neuroprostheses requires that somatosensory feedback be provided to the tetraplegic patient or amputee. Given the complexity of state-of-the-art prosthetic limbs and, thus, the huge state space they can traverse, it is desirable to minimize the need for the patient to learn associations between events impinging on the limb and arbitrary sensations. Accordingly, we have developed approaches to intuitively convey sensory information that is critical for object manipulation--information about contact location, pressure, and timing--through intracortical microstimulation of primary somatosensory cortex. In experiments with nonhuman primates, we show that we can elicit percepts that are projected to a localized patch of skin and that track the pressure exerted on the skin. In a real-time application, we demonstrate that animals can perform a tactile discrimination task equally well whether mechanical stimuli are delivered to their native fingers or to a prosthetic one. Finally, we propose that the timing of contact events can be signaled through phasic intracortical microstimulation at the onset and offset of object contact that mimics the ubiquitous on and off responses observed in primary somatosensory cortex to complement slowly varying pressure-related feedback. We anticipate that the proposed biomimetic feedback will considerably increase the dexterity and embodiment of upper-limb neuroprostheses and will constitute an important step in restoring touch to individuals who have lost it.

Mechanical energy profiles of the combined ankle-foot system in normal gait: insights for prosthetic designs.

PubMed

Takahashi, Kota Z; Stanhope, Steven J

2013-09-01

Over the last half-century, the field of prosthetic engineering has continuously evolved with much attention being dedicated to restoring the mechanical energy properties of ankle joint musculatures during gait. However, the contributions of 'distal foot structures' (e.g., foot muscles, plantar soft tissue) have been overlooked. Therefore, the purpose of this study was to quantify the total mechanical energy profiles (e.g., power, work, and work-ratio) of the natural ankle-foot system (NAFS) by combining the contributions of the ankle joint and all distal foot structures during stance in level-ground steady state walking across various speeds (0.4, 0.6, 0.8 and 1.0 statures/s). The results from eleven healthy subjects walking barefoot indicated ankle joint and distal foot structures generally performed opposing roles: the ankle joint performed net positive work that systematically increased its energy generation with faster walking speeds, while the distal foot performed net negative work that systematically increased its energy absorption with faster walking speeds. Accounting for these simultaneous effects, the combined ankle-foot system exhibited increased work-ratios with faster walking. Most notably, the work-ratio was not significantly greater than 1.0 during the normal walking speed of 0.8 statures/s. Therefore, a prosthetic design that strategically exploits passive-dynamic properties (e.g., elastic energy storage and return) has the potential to replicate the mechanical energy profiles of the NAFS during level-ground steady-state walking. Copyright © 2013 Elsevier B.V. All rights reserved.

Restoration of the Donor Face After Facial Allotransplantation

PubMed Central

Grant, Gerald T.; Liacouras, Peter; Santiago, Gabriel F.; Garcia, Juan R.; Al Rakan, Mohammed; Murphy, Ryan; Armand, Mehran; Gordon, Chad R.

2014-01-01

Introduction Current protocols for facial transplantation include the mandatory fabrication of an alloplastic “mask” to restore the congruency of the donor site in the setting of “open casket” burial. However, there is currently a paucity of literature describing the current state-of-the-art and available options. Methods During this study, we identified that most of donor masks are fabricated using conventional methods of impression, molds, silicone, and/or acrylic application by an experienced anaplastologist or maxillofacial prosthetics technician. However, with the recent introduction of several enhanced computer-assisted technologies, our facial transplant team hypothesized that there were areas for improvement with respect to cost and preparation time. Results The use of digital imaging for virtual surgical manipulation, computer-assisted planning, and prefabricated surgical cutting guides—in the setting of facial transplantation—provided us a novel opportunity for digital design and fabrication of a donor mask. The results shown here demonstrate an acceptable appearance for “open-casket” burial while maintaining donor identity after facial organ recovery. Conclusions Several newer techniques for fabrication of facial transplant donor masks exist currently and are described within the article. These encompass digital impression, digital design, and additive manufacturing technology. PMID:24835867

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

PubMed

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.

Pinch-force-magnification mechanism of low degree of freedom EMG prosthetic hand for children.

PubMed

Ye, Hesong; Sakoda, Shintaro; Jiang, Yinlai; Morishita, Soichiro; Yokoi, Hiroshi

2015-01-01

EMG prosthetic hands are being extensively studied for the disabled who need them not only for cosmesis but also for the functions to help them with basic daily activities. However, most EMG prosthetic hands are developed for adults. Since the early use of prosthetic hands is important for the children to accept and adapt to them, we are developing low degrees of freedom (DoF) prosthetic hand that is suitable for children. Due to the limited size of a child's hand, the servo motor which drives the MP joint are small-sized and low-power. Hence, a pinch-force-magnification mechanism is required to improve the pinch force of the EMG prosthetic hand. In this paper we designed a wire-driven mechanism which can magnify pinch force by increasing the length of the MP joint's moment arm. Pinch force measurement experiment validated that the pinch force of the prosthetic hand with the mechanism is more than twice of that of the hand with direct drive.

Developing prescribing guidelines for microprocessor-controlled prosthetic knees in the South East England.

PubMed

Sedki, Imad; Fisher, Keren

2015-06-01

Microprocessor-controlled prosthetic knees have gained increasing popularity over the last decade. Research supports their provision to address specific problems or to achieve certain rehabilitation goals. However, there are yet no agreed protocols or prescribing criteria to assist clinicians in the identification and appropriate selection of suitable users. The aim is to reach professionals' agreement on specific prescribing guidelines for microprocessor-controlled prosthetic knees. The study involved multidisciplinary teams from the Inter Regional Prosthetic Audit Group, representing nine Prosthetic Rehabilitation Centres in the South East England region. We used the Delphi technique with a total of three rounds to reach professionals' agreement. The prescribing guidelines were agreed and will be reviewed and updated depending on new research evidence and technical advances. This project is highly useful for professionals in a clinic setting to aid in appropriate patient selection and to justify the cost of prescribing microprocessor-controlled prosthetic knees. © The International Society for Prosthetics and Orthotics 2014.

Biomechanics of the ankle-foot system during stair ambulation: implications for design of advanced ankle-foot prostheses.

PubMed

Sinitski, Emily H; Hansen, Andrew H; Wilken, Jason M

2012-02-02

Unilateral lower limb prosthesis users display temporal, kinematic, and kinetic asymmetries between limbs while ascending and descending stairs. These asymmetries are due, in part, to the inability of current prosthetic devices to effectively mimic normal ankle function. The purpose of this study was to provide a comprehensive set of biomechanical data for able-bodied and unilateral transtibial amputee (TTA) ankle-foot systems for level-ground (LG), stair ascent (SA), and stair descent (SD), and to characterize deviations from normal performance associated with prosthesis use. Ankle joint kinematics, kinetics, torque-angle curves, and effective shapes were calculated for twelve able-bodied individuals and twelve individuals with TTA. The data from this study demonstrated the prosthetic limb can more effectively mimic the range of motion and power output of a normal ankle-foot during LG compared to SA and SD. There were larger differences between the prosthetic and able-bodied limbs during SA and SD, most evident in the torque-angle curves and effective shapes. These data can be used by persons designing ankle-foot prostheses and provide comparative data for assessment of future ankle-foot prosthesis designs. Published by Elsevier Ltd.

Thrombolytic therapy for mitral valve thrombosis.

PubMed

Lin, T K; Tsai, L M; Chen, J H; Yang, Y J

1997-05-01

A 44-year-old man with a St. Jude mitral valve was admitted because of progressive pulmonary edema. He was diagnosed with prosthetic heart valve thrombosis (PHVT) based on the findings of "muffled" prosthetic valve clicks. Doppler echocardiographic evidence of severe mitral stenosis and transesophageal echocardiographic evidence of limited mitral valve motility. Because the patient hesitated to undergo our recommended surgical treatment, he was immediately treated with intravenous recombinant tissue plasminogen activator (100 mg over 3 h) followed by heparinization. Two hours after the thrombolytic therapy, the prosthetic valve clicks became clearly audible and his congestive symptoms were dramatically improved. Follow-up echocardiography no longer-showed significant mitral valve obstruction. A transient cerebral ischemic attack occurred at the end of thrombolytic therapy but there were no neurologic sequalae. The patient, on warfarin therapy, was well at follow-up 8 months after discharge. Surgical intervention has long been the standard therapy for patients with PHVT. Our case experience suggests that thrombolytic therapy may be considered as an effective alternative to surgical intervention for selected patients with PHVT. In this report, we also review the current literature regarding the indications, effectiveness and safety of thrombolytic therapy in PHVT.

Evaluation of mitral valve replacement anchoring in a phantom

NASA Astrophysics Data System (ADS)

McLeod, A. Jonathan; Moore, John; Lang, Pencilla; Bainbridge, Dan; Campbell, Gordon; Jones, Doug L.; Guiraudon, Gerard M.; Peters, Terry M.

2012-02-01

Conventional mitral valve replacement requires a median sternotomy and cardio-pulmonary bypass with aortic crossclamping and is associated with significant mortality and morbidity which could be reduced by performing the procedure off-pump. Replacing the mitral valve in the closed, off-pump, beating heart requires extensive development and validation of surgical and imaging techniques. Image guidance systems and surgical access for off-pump mitral valve replacement have been previously developed, allowing the prosthetic valve to be safely introduced into the left atrium and inserted into the mitral annulus. The major remaining challenge is to design a method of securely anchoring the prosthetic valve inside the beating heart. The development of anchoring techniques has been hampered by the expense and difficulty in conducting large animal studies. In this paper, we demonstrate how prosthetic valve anchoring may be evaluated in a dynamic phantom. The phantom provides a consistent testing environment where pressure measurements and Doppler ultrasound can be used to monitor and assess the valve anchoring procedures, detecting pararvalvular leak when valve anchoring is inadequate. Minimally invasive anchoring techniques may be directly compared to the current gold standard of valves sutured under direct vision, providing a useful tool for the validation of new surgical instruments.

Evolution and update on current devices for prosthetic breast reconstruction

PubMed Central

2015-01-01

Over the past decade, the leading breast reconstruction modality has shifted from autologous tissue to implants. This trend reversal is multi-factorial but includes increasing bilateral mastectomies and the more widespread acceptance of implants due to stringent quality and safety regulatory surveillance by the US Food and Drug Administration (FDA). Since 2012, the US FDA has approved several new implant styles, shapes and textures, increasing the choices for patients and surgeons. Predictable, superior aesthetic results after prosthetic breast reconstruction are attainable, but require thoughtful planning, precise surgical technique and appropriate device selection based on several different patient and surgeon parameters, such as patient desires, body mass index, breast shape, mastectomy flap quality and tissue based bio-dimensional assessment. This article briefly reviews historic devices used in prosthetic breast reconstruction beginning in the 1960s through the modern generation devices used today. We reflect on the rigorous hurdles endured over the last several decades leading to the approval of silicone gel devices, along with their well-established safety and efficacy. The various implant characteristics can affect feel and performance of the device. The many different styles and features of implants and expanders are described emphasizing surgical indications, advantages and disadvantages of each device. PMID:26005642

Mechanical design and performance specifications of anthropomorphic prosthetic hands: a review.

PubMed

Belter, Joseph T; Segil, Jacob L; Dollar, Aaron M; Weir, Richard F

2013-01-01

In this article, we set forth a detailed analysis of the mechanical characteristics of anthropomorphic prosthetic hands. We report on an empirical study concerning the performance of several commercially available myoelectric prosthetic hands, including the Vincent, iLimb, iLimb Pulse, Bebionic, Bebionic v2, and Michelangelo hands. We investigated the finger design and kinematics, mechanical joint coupling, and actuation methods of these commercial prosthetic hands. The empirical findings are supplemented with a compilation of published data on both commercial and prototype research prosthetic hands. We discuss numerous mechanical design parameters by referencing examples in the literature. Crucial design trade-offs are highlighted, including number of actuators and hand complexity, hand weight, and grasp force. Finally, we offer a set of rules of thumb regarding the mechanical design of anthropomorphic prosthetic hands.

Microprocessor prosthetic knees.

PubMed

Berry, Dale

2006-02-01

This article traces the development of microprocessor prosthetic knees from early research in the 1970s to the present. Read about how microprocessor knees work, functional options, patient selection, and the future of this prosthetic.

The mechanical properties of infrainguinal vascular bypass grafts: their role in influencing patency.

PubMed

Sarkar, S; Salacinski, H J; Hamilton, G; Seifalian, A M

2006-06-01

When autologous vein is unavailable, prosthetic graft materials, particularly expanded polytetrafluoroethylene are used for peripheral arterial revascularisation. Poor long term patency of prosthetic materials is due to distal anastomotic intimal hyperplasia. Intimal hyperplasia is directly linked to shear stress abnormalities at the vessel wall. Compliance and calibre mismatch between native vessel and graft, as well as anastomotic line stress concentration contribute towards unnatural wall shear stress. High porosity reduces graft compliance by causing fibrovascular infiltration, whereas low porosity discourages the development of an endothelial lining and hence effective antithrombogenicity. Therefore, consideration of mechanical properties is necessary in graft development. Current research into synthetic vascular grafts concentrates on simulating the mechanical properties of native arteries and tissue engineering aims to construct a new biological arterial conduit.

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

PubMed

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.

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

PubMed

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 <0.001), more additional surgery (3.3 vs. 0.07; p <0.001) and longer total bed days (31.6 vs. 7.9 days; p <0.001). In addition they had more inpatient, outpatient and emergency department visits (p <0.001, respectively). For patients with 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 <0.001). The demand for arthroplasty continues to grow and with that, the number of 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.

Fiber-array based optogenetic prosthetic system for stimulation therapy

NASA Astrophysics Data System (ADS)

Gu, Ling; Cote, Chris; Tejeda, Hector; Mohanty, Samarendra

2012-02-01

Recent advent of optogenetics has enabled activation of genetically-targeted neuronal cells using low intensity blue light with high temporal precision. Since blue light is attenuated rapidly due to scattering and absorption in neural tissue, optogenetic treatment of neurological disorders may require stimulation of specific cell types in multiple regions of the brain. Further, restoration of certain neural functions (vision, and auditory etc) requires accurate spatio-temporal stimulation patterns rather than just precise temporal stimulation. In order to activate multiple regions of the central nervous system in 3D, here, we report development of an optogenetic prosthetic comprising of array of fibers coupled to independently-controllable LEDs. This design avoids direct contact of LEDs with the brain tissue and thus does not require electrical and heat isolation, which can non-specifically stimulate and damage the local brain regions. The intensity, frequency, and duty cycle of light pulses from each fiber in the array was controlled independently using an inhouse developed LabView based program interfaced with a microcontroller driving the individual LEDs. While the temporal profile of the light pulses was controlled by varying the current driving the LED, the beam profile emanating from each fiber tip could be sculpted by microfabrication of the fiber tip. The fiber array was used to stimulate neurons, expressing channelrhodopsin-2, in different locations within the brain or retina. Control of neural activity in the mice cortex, using the fiber-array based prosthetic, is evaluated from recordings made with multi-electrode array (MEA). We also report construction of a μLED array based prosthetic for spatio-temporal stimulation of cortex.

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

PubMed

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.

Development of Subischial Prosthetic Sockets with Vacuum-Assisted Suspension for Highly Active Persons with Transfemoral Amputations

DTIC Science & Technology

2014-10-01

Award Number: W81XWH-10-1-0744 TITLE: Development of Subischial Prosthetic Sockets with Vacuum...REPORT TYPE Annual 3. DATES COVERED 15 Sep 2013 – 14 Sep 2014 4. TITLE AND SUBTITLE Development of Subischial Prosthetic Sockets with Vacuum...to develop a highly flexible sub-ischial prosthetic socket with assisted-vacuum suspension for highly active persons with transfemoral amputation. The

Viability of Controlling Prosthetic Hand Utilizing Electroencephalograph (EEG) Dataset Signal

NASA Astrophysics Data System (ADS)

Miskon, Azizi; A/L Thanakodi, Suresh; Raihan Mazlan, Mohd; Mohd Haziq Azhar, Satria; Nooraya Mohd Tawil, Siti

2016-11-01

This project presents the development of an artificial hand controlled by Electroencephalograph (EEG) signal datasets for the prosthetic application. The EEG signal datasets were used as to improvise the way to control the prosthetic hand compared to the Electromyograph (EMG). The EMG has disadvantages to a person, who has not used the muscle for a long time and also to person with degenerative issues due to age factor. Thus, the EEG datasets found to be an alternative for EMG. The datasets used in this work were taken from Brain Computer Interface (BCI) Project. The datasets were already classified for open, close and combined movement operations. It served the purpose as an input to control the prosthetic hand by using an Interface system between Microsoft Visual Studio and Arduino. The obtained results reveal the prosthetic hand to be more efficient and faster in response to the EEG datasets with an additional LiPo (Lithium Polymer) battery attached to the prosthetic. Some limitations were also identified in terms of the hand movements, weight of the prosthetic, and the suggestions to improve were concluded in this paper. Overall, the objective of this paper were achieved when the prosthetic hand found to be feasible in operation utilizing the EEG datasets.

Comparison of prosthetic feet prescribed to active individuals using ISO standards.

PubMed

Mason, Zachary D; Pearlman, Jon; Cooper, Rory A; Laferrier, Justin Z

2011-12-01

Little research has been done on the robustness of prosthetic feet prescribed to military personnel, and manufacturers are not required to test their products prior to sale. This is problematic because the prosthetic feet used by active individuals are subjected to loading conditions not seen in normal gait. To evaluate whether commercially available heavy-duty prosthetic feet intended for use by military personnel meet ISO 10328 standards. Bench testing of heavy-duty prosthetic feet using ISO 10328 standards. Prosthetic feet from three different manufacturers were tested according to ISO 10328 standards, using a testing frame fitted with axial load and displacement transducers. Pass/fail information was recorded as well as the stiffness and creep of each foot before and after cyclic testing. All feet passed the ISO 10328 standards at the highest loading level, and some significant differences were found within a given model of prosthesis when comparing stiffness and creep before and after cyclic testing. This study demonstrated that manufacturers of heavy-duty prosthetic feet adhere to the voluntary ISO 10328 standards. However, these standards may be insufficient because the tests simulate only idealized gait. Further development of the standards may be necessary to reproduce the circumstances that occur during extreme usage to ensure that prosthetic feet do not fail.

Circuit For Control Of Electromechanical Prosthetic Hand

NASA Technical Reports Server (NTRS)

Bozeman, Richard J., Jr.

1995-01-01

Proposed circuit for control of electromechanical prosthetic hand derives electrical control signals from shoulder movements. Updated, electronic version of prosthesis, that includes two hooklike fingers actuated via cables from shoulder harness. Circuit built around favored shoulder harness, provides more dexterous movement, without incurring complexity of computer-controlled "bionic" or hydraulically actuated devices. Additional harness and potentiometer connected to similar control circuit mounted on other shoulder. Used to control stepping motor rotating hand about prosthetic wrist to one of number of angles consistent with number of digital outputs. Finger-control signals developed by circuit connected to first shoulder harness transmitted to prosthetic hand via sliprings at prosthetic wrist joint.

Improving Fine Control of Grasping Force during Hand–Object Interactions for a Soft Synergy-Inspired Myoelectric Prosthetic Hand

PubMed Central

Fu, Qiushi; Santello, Marco

2018-01-01

The concept of postural synergies of the human hand has been shown to potentially reduce complexity in the neuromuscular control of grasping. By merging this concept with soft robotics approaches, a multi degrees of freedom soft-synergy prosthetic hand [SoftHand-Pro (SHP)] was created. The mechanical innovation of the SHP enables adaptive and robust functional grasps with simple and intuitive myoelectric control from only two surface electromyogram (sEMG) channels. However, the current myoelectric controller has very limited capability for fine control of grasp forces. We addressed this challenge by designing a hybrid-gain myoelectric controller that switches control gains based on the sensorimotor state of the SHP. This controller was tested against a conventional single-gain (SG) controller, as well as against native hand in able-bodied subjects. We used the following tasks to evaluate the performance of grasp force control: (1) pick and place objects with different size, weight, and fragility levels using power or precision grasp and (2) squeezing objects with different stiffness. Sensory feedback of the grasp forces was provided to the user through a non-invasive, mechanotactile haptic feedback device mounted on the upper arm. We demonstrated that the novel hybrid controller enabled superior task completion speed and fine force control over SG controller in object pick-and-place tasks. We also found that the performance of the hybrid controller qualitatively agrees with the performance of native human hands. PMID:29375360

Adipose and mammary epithelial tissue engineering.

PubMed

Zhu, Wenting; Nelson, Celeste M

2013-01-01

Breast reconstruction is a type of surgery for women who have had a mastectomy, and involves using autologous tissue or prosthetic material to construct a natural-looking breast. Adipose tissue is the major contributor to the volume of the breast, whereas epithelial cells comprise the functional unit of the mammary gland. Adipose-derived stem cells (ASCs) can differentiate into both adipocytes and epithelial cells and can be acquired from autologous sources. ASCs are therefore an attractive candidate for clinical applications to repair or regenerate the breast. Here we review the current state of adipose tissue engineering methods, including the biomaterials used for adipose tissue engineering and the application of these techniques for mammary epithelial tissue engineering. Adipose tissue engineering combined with microfabrication approaches to engineer the epithelium represents a promising avenue to replicate the native structure of the breast.

Adipose and mammary epithelial tissue engineering

PubMed Central

Zhu, Wenting; Nelson, Celeste M.

2013-01-01

Breast reconstruction is a type of surgery for women who have had a mastectomy, and involves using autologous tissue or prosthetic material to construct a natural-looking breast. Adipose tissue is the major contributor to the volume of the breast, whereas epithelial cells comprise the functional unit of the mammary gland. Adipose-derived stem cells (ASCs) can differentiate into both adipocytes and epithelial cells and can be acquired from autologous sources. ASCs are therefore an attractive candidate for clinical applications to repair or regenerate the breast. Here we review the current state of adipose tissue engineering methods, including the biomaterials used for adipose tissue engineering and the application of these techniques for mammary epithelial tissue engineering. Adipose tissue engineering combined with microfabrication approaches to engineer the epithelium represents a promising avenue to replicate the native structure of the breast. PMID:23628872

The Melody® valve and Ensemble® delivery system for transcatheter pulmonary valve replacement

PubMed Central

McElhinney, Doff B; Hennesen, Jill T

2013-01-01

The Melody® transcatheter pulmonary valve (TPV) is a percutaneous valve system designed for the treatment of obstruction and/or regurgitation of prosthetic conduits placed between the right ventricle and pulmonary arteries in patients with congenital heart disease. In 2000, Melody TPV became the first transcatheter valve implanted in a human; in 2006 it became the first transcatheter valve commercially available anywhere in the world; and in 2010 it was launched as the first commercially available transcatheter valve in the United States. In this review, we present the clinical background against which the Melody valve was developed and implemented, introduce the rationale for and challenges of transcatheter valve technology for this population, outline the history and technical details of its development and use, and summarize currently available data concerning the performance of the device. PMID:23834411

Multisession, noninvasive closed-loop neuroprosthetic control of grasping by upper limb amputees.

PubMed

Agashe, H A; Paek, A Y; Contreras-Vidal, J L

2016-01-01

Upper limb amputation results in a severe reduction in the quality of life of affected individuals due to their inability to easily perform activities of daily living. Brain-machine interfaces (BMIs) that translate grasping intent from the brain's neural activity into prosthetic control may increase the level of natural control currently available in myoelectric prostheses. Current BMI techniques demonstrate accurate arm position and single degree-of-freedom grasp control but are invasive and require daily recalibration. In this study we tested if transradial amputees (A1 and A2) could control grasp preshaping in a prosthetic device using a noninvasive electroencephalography (EEG)-based closed-loop BMI system. Participants attempted to grasp presented objects by controlling two grasping synergies, in 12 sessions performed over 5 weeks. Prior to closed-loop control, the first six sessions included a decoder calibration phase using action observation by the participants; thereafter, the decoder was fixed to examine neuroprosthetic performance in the absence of decoder recalibration. Ability of participants to control the prosthetic was measured by the success rate of grasping; ie, the percentage of trials within a session in which presented objects were successfully grasped. Participant A1 maintained a steady success rate (63±3%) across sessions (significantly above chance [41±5%] for 11 sessions). Participant A2, who was under the influence of pharmacological treatment for depression, hormone imbalance, pain management (for phantom pain as well as shoulder joint inflammation), and drug dependence, achieved a success rate of 32±2% across sessions (significantly above chance [27±5%] in only two sessions). EEG signal quality was stable across sessions, but the decoders created during the first six sessions showed variation, indicating EEG features relevant to decoding at a smaller timescale (100ms) may not be stable. Overall, our results show that (a) an EEG-based BMI for grasping is a feasible strategy for further investigation of prosthetic control by amputees, and (b) factors that may affect brain activity such as medication need further examination to improve accuracy and stability of BMI performance. © 2016 Elsevier B.V. All rights reserved.

[Joint Prosthetic Infection: UpDate Approaches to Diagnosis and Treatment].

PubMed

Belov, B S; Makarov, S A; Byalik, E I

2015-01-01

At present endoprosthetics of the joints is considered as a progressive and ever developing method in the surgical treatment of patients with affection of the locomotor system of any genesis. Hence, increasing of the number of endoprosthetic results in increasing of the number of patients with periprosthetic infection. Polymorphism of the clinical picture and inspecificity of the diagnostic tests often cause a delay in the diagnosis of the joint prosthetic infection (JPI) and consequently the late treatment. The contemporary data on the etiology, epidemiology, clinical picture and diagnosis of JPI are presented. The importance of cooperated treatment of JPI, i.e. combination of the surgical management and etiotropic antibacterial therapy is indicated. The choice of the concrete treatment method is defined by the patient state, comorbid pathology, the infection severity and duration.

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

PubMed

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.

Review of Prosthetic Joint Infection from Listeria monocytogenes.

PubMed

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.

Cetacean Swimming with Prosthetic Limbs

NASA Astrophysics Data System (ADS)

Bode-Oke, Ayodeji; Ren, Yan; Dong, Haibo; Fish, Frank

2016-11-01

During entanglement in fishing gear, dolphins can suffer abrasions and amputations of flukes and fins. As a result, if the dolphin survives the ordeal, swimming performance is altered. Current rehabilitation technques is the use of prosthesis to regain swimming ability. In this work, analyses are focused on two dolphins with locomotive impairment; Winter (currently living in Clearwater Marine Aquarium in Florida) and Fuji (lived in Okinawa Churaumi Aquarium in Japan). Fuji lost about 75% of its fluke surface to necrosis (death of cells) and Winter lost its tail due to amputation. Both dolphins are aided by prosthetic tails that mimic the shape of a real dolphin tail. Using 3D surface reconstruction techniques and a high fidelity Computational Fluid Dynamics (CFD) flow solver, we were able to elucidate the kinematics and hydrodynamics and fluke deformation of these swimmers to clarify the effectiveness of prostheses in helping the dolphins regain their swimming ability. Associated with the performance, we identified distinct features in the wake structures that can explain this gap in the performance compared to a healthy dolphin. This work was supported by ONR MURI Grant Number N00014-14-1-0533.

A two DoF finger for a biomechatronic artificial hand.

PubMed

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.

Application of dexterous space robotics technology to myoelectric prostheses

NASA Astrophysics Data System (ADS)

Hess, Clifford; Li, Larry C. H.; Farry, Kristin A.; Walker, Ian D.

1994-02-01

Future space missions will require robots equipped with highly dexterous robotic hands to perform a variety of tasks. A major technical challenge in making this possible is an improvement in the way these dexterous robotic hands are remotely controlled or teleoperated. NASA is currently investigating the feasibility of using myoelectric signals to teleoperate a dexterous robotic hand. In theory, myoelectric control of robotic hands will require little or no mechanical parts and will greatly reduce the bulk and weight usually found in dexterous robotic hand control devices. An improvement in myoelectric control of multifinger hands will also benefit prosthetics users. Therefore, as an effort to transfer dexterous space robotics technology to prosthetics applications and to benefit from existing myoelectric technology, NASA is collaborating with the Limbs of Love Foundation, the Institute for Rehabilitation and Research, and Rice University in developing improved myoelectric control multifinger hands and prostheses. In this paper, we will address the objectives and approaches of this collaborative effort and discuss the technical issues associated with myoelectric control of multifinger hands. We will also report our current progress and discuss plans for future work.

Application of dexterous space robotics technology to myoelectric prostheses

NASA Technical Reports Server (NTRS)

Hess, Clifford; Li, Larry C. H.; Farry, Kristin A.; Walker, Ian D.

1994-01-01

Future space missions will require robots equipped with highly dexterous robotic hands to perform a variety of tasks. A major technical challenge in making this possible is an improvement in the way these dexterous robotic hands are remotely controlled or teleoperated. NASA is currently investigating the feasibility of using myoelectric signals to teleoperate a dexterous robotic hand. In theory, myoelectric control of robotic hands will require little or no mechanical parts and will greatly reduce the bulk and weight usually found in dexterous robotic hand control devices. An improvement in myoelectric control of multifinger hands will also benefit prosthetics users. Therefore, as an effort to transfer dexterous space robotics technology to prosthetics applications and to benefit from existing myoelectric technology, NASA is collaborating with the Limbs of Love Foundation, the Institute for Rehabilitation and Research, and Rice University in developing improved myoelectric control multifinger hands and prostheses. In this paper, we will address the objectives and approaches of this collaborative effort and discuss the technical issues associated with myoelectric control of multifinger hands. We will also report our current progress and discuss plans for future work.

Characterizing the Mechanical Properties of Running-Specific Prostheses

PubMed Central

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

2016-01-01

The mechanical stiffness of running-specific prostheses likely affects the functional abilities of athletes with leg amputations. However, each prosthetic manufacturer recommends prostheses based on subjective stiffness categories rather than performance based metrics. The actual mechanical stiffness values of running-specific prostheses (i.e. kN/m) are unknown. Consequently, we sought to characterize and disseminate the stiffness values of running-specific prostheses so that researchers, clinicians, and athletes can objectively evaluate prosthetic function. We characterized the stiffness values of 55 running-specific prostheses across various models, stiffness categories, and heights using forces and angles representative of those measured from athletes with transtibial amputations during running. Characterizing prosthetic force-displacement profiles with a 2nd degree polynomial explained 4.4% more of the variance than a linear function (p<0.001). The prosthetic stiffness values of manufacturer recommended stiffness categories varied between prosthetic models (p<0.001). Also, prosthetic stiffness was 10% to 39% less at angles typical of running 3 m/s and 6 m/s (10°-25°) compared to neutral (0°) (p<0.001). Furthermore, prosthetic stiffness was inversely related to height in J-shaped (p<0.001), but not C-shaped, prostheses. Running-specific prostheses should be tested under the demands of the respective activity in order to derive relevant characterizations of stiffness and function. In all, our results indicate that when athletes with leg amputations alter prosthetic model, height, and/or sagittal plane alignment, their prosthetic stiffness profiles also change; therefore variations in comfort, performance, etc. may be indirectly due to altered stiffness. PMID:27973573

Upper Extremity Amputations and Prosthetics

PubMed Central

Ovadia, Steven A.; Askari, Morad

2015-01-01

Upper extremity amputations are most frequently indicated by severe traumatic injuries. The location of the injury will determine the level of amputation. Preservation of extremity length is often a goal. The amputation site will have important implications on the functional status of the patient and options for prosthetic reconstruction. Advances in amputation techniques and prosthetic reconstructions promote improved quality of life. In this article, the authors review the principles of upper extremity amputation, including techniques, amputation sites, and prosthetic reconstructions. PMID:25685104

Influence of the prosthetic arm length (palatal position) of zygomatic implants upon patient satisfaction

PubMed Central

Pellicer-Chover, Hilario; Cervera-Ballester, Juan; Peñarrocha-Oltra, David; Bagán, Leticia; Peñarrocha-Diago, María

2016-01-01

Background To assess the influence of the prosthetic arm length (palatal position) of zygomatic implants upon patient comfort and stability, speech, functionality and overall satisfaction. Material and Methods A retrospective clinical study was made of patients subjected to rehabilitation of atrophic maxilla with complete maxillary implant-supported fixed prostheses involving a minimum of two zygomatic implants (one on each side) in conjunction with premaxillary implants, and with 12 months of follow-up after implant loading. Subjects used a VAS to score general satisfaction, comfort and stability, speech and functionality, and the results were analyzed in relation to the prosthetic arm length of the zygomatic implants 12 months after prosthetic delivery. Results Twenty-two patients participated in the study, receiving 22 prostheses anchored on 148 implants (44 were zygomatic and 94 were conventional implants). The mean right and left prosthetic arm length was 5.9±2.4 mm and 6.1±2.7 mm, respectively, with no statistically significant differences between them (p=0.576). The mean scores referred to comfort/retention, speech, functionality and overall satisfaction were high - no correlation being found between prosthetic arm length and patient satisfaction (p=0.815). Conclusions No relationship could be identified between prosthetic arm length (palatal position) and patient satisfaction. Key words:Zygomatic implants, patient satisfaction, zygomatic prosthesis, prosthetic arm length. PMID:26946206

38 CFR 17.150 - Prosthetic and similar appliances.

Code of Federal Regulations, 2010 CFR

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...

Conventional and molecular diagnostic strategies for prosthetic joint infections.

PubMed

Esteban, Jaime; Sorlí, Luisa; Alentorn-Geli, Eduard; Puig, Lluís; Horcajada, Juan P

2014-01-01

An accurate diagnosis of prosthetic joint infection (PJI) is the mainstay for an optimized clinical management. This review analyzes different diagnostic strategies of PJI, with special emphasis on molecular diagnostic tools and their current and future applications. Until now, the culture of periprosthetic tissues has been considered the gold standard for the diagnosis of PJI. However, sonication of the implant increases the sensitivity of those cultures and is being increasingly adopted by many centers. Molecular diagnostic methods compared with intraoperative tissue culture, especially if combined with sonication, have a higher sensitivity, a faster turnaround time and are not influenced by previous antimicrobial therapy. However, they still lack a system for detection of antimicrobial susceptibility, which is crucial for an optimized and less toxic therapy of PJI. More studies are needed to assess the clinical value of these methods and their cost-effectiveness.

Electronic approaches to restoration of sight

NASA Astrophysics Data System (ADS)

Goetz, G. A.; Palanker, D. V.

2016-09-01

Retinal prostheses are a promising means for restoring sight to patients blinded by the gradual atrophy of photoreceptors due to retinal degeneration. They are designed to reintroduce information into the visual system by electrically stimulating surviving neurons in the retina. This review outlines the concepts and technologies behind two major approaches to retinal prosthetics: epiretinal and subretinal. We describe how the visual system responds to electrical stimulation. We highlight major differences between direct encoding of the retinal output with epiretinal stimulation, and network-mediated response with subretinal stimulation. We summarize results of pre-clinical evaluation of prosthetic visual functions in- and ex vivo, as well as the outcomes of current clinical trials of various retinal implants. We also briefly review alternative, non-electronic, approaches to restoration of sight to the blind, and conclude by suggesting some perspectives for future advancement in the field.

Electronic Approaches to Restoration of Sight

PubMed Central

Goetz, G A; Palanker, D V

2016-01-01

Retinal prostheses are a promising means for restoring sight to patients blinded by the gradual atrophy of photoreceptors due to retinal degeneration. They are designed to reintroduce information into the visual system by electrically stimulating surviving neurons in the retina. This review outlines the concepts and technologies behind two major approaches to retinal prosthetics: epiretinal and subretinal. We describe how the visual system responds to electrical stimulation. We highlight major differences between direct encoding of the retinal output with epiretinal stimulation, and network-mediated response with subretinal stimulation. We summarize results of pre-clinical evaluation of prosthetic visual functions in- and ex-vivo, as well as the outcomes of current clinical trials of various retinal implants. We also briefly review alternative, non-electronic, approaches to restoration of sight to the blind, and conclude by suggesting some perspectives for future advancement in the field. PMID:27502748

Correctness of multi-detector-row computed tomography for diagnosing mechanical prosthetic heart valve disorders using operative findings as a gold standard.

PubMed

Tsai, I-Chen; Lin, Yung-Kai; Chang, Yen; Fu, Yun-Ching; Wang, Chung-Chi; Hsieh, Shih-Rong; Wei, Hao-Ji; Tsai, Hung-Wen; Jan, Sheng-Ling; Wang, Kuo-Yang; Chen, Min-Chi; Chen, Clayton Chi-Chang

2009-04-01

The purpose was to compare the findings of multi-detector computed tomography (MDCT) in prosthetic valve disorders using the operative findings as a gold standard. In a 3-year period, we prospectively enrolled 25 patients with 31 prosthetic heart valves. MDCT and transthoracic echocardiography (TTE) were done to evaluate pannus formation, prosthetic valve dysfunction, suture loosening (paravalvular leak) and pseudoaneurysm formation. Patients indicated for surgery received an operation within 1 week. The MDCT findings were compared with the operative findings. One patient with a Björk-Shiley valve could not be evaluated by MDCT due to a severe beam-hardening artifact; thus, the exclusion rate for MDCT was 3.2% (1/31). Prosthetic valve disorders were suspected in 12 patients by either MDCT or TTE. Six patients received an operation that included three redo aortic valve replacements, two redo mitral replacements and one Amplatzer ductal occluder occlusion of a mitral paravalvular leak. The concordance of MDCT for diagnosing and localizing prosthetic valve disorders and the surgical findings was 100%. Except for images impaired by severe beam-hardening artifacts, MDCT provides excellent delineation of prosthetic valve disorders.

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

PubMed

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.

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

PubMed

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.

Rotationplasty with vascular reconstruction for prosthetic knee joint infection.

PubMed

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.

38 CFR 3.810 - Clothing allowance.

Code of Federal Regulations, 2014 CFR

2014-07-01

... prosthetic or orthopedic appliance (including, but not limited to, a wheelchair) which tends to wear or tear... service-connected disability or disabilities, wears or uses one qualifying prosthetic or orthopedic... allowance for each prosthetic or orthopedic appliance (including, but not limited to, a wheelchair) or...

Prosthetic Aortic Valves: Challenges and Solutions

PubMed Central

Musumeci, Lucia; Jacques, Nicolas; Hego, Alexandre; Nchimi, Alain; Lancellotti, Patrizio; Oury, Cécile

2018-01-01

Aortic Valve Disease (AVD) is the most common Valvular Heart Disease (VHD), affecting millions of people worldwide. Severe AVD is treated in most cases with prosthetic aortic valve replacement, which involves the substitution of the native aortic valve with a prosthetic one. In this review we will discuss the different types of prosthetic aortic valves available for implantation and the challenges faced by patients, medical doctors, researchers and manufacturers, as well as the approaches that are taken to overcome them. PMID:29868612

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

PubMed

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.

Concerns of anophthalmic patients-a comparison between cryolite glass and polymethyl methacrylate prosthetic eye wearers.

PubMed

Rokohl, Alexander C; Koch, Konrad R; Adler, Werner; Trester, Marc; Trester, Wolfgang; Pine, Nicola S; Pine, Keith R; Heindl, Ludwig M

2018-06-01

To compare the concerns of experienced cryolite glass and (poly)methyl methacrylate (PMMA) prosthetic eye wearers. One hundred six experienced cryolite glass and 63 experienced PMMA prosthetic eye wearers completed an anonymous questionnaire regarding general and specific prosthetic eye concerns at least 2 years after natural eye loss. From these independent anophthalmic populations, we identified 34 case-control pairs matched for the known influencing demographic variables of gender, occupation, age, and time since natural eye loss. The levels of concern were significantly lower in the cryolite glass group than those in the PMMA group for the following: loss of balance (p < 0.001), phantom sight vision (p < 0.001), pain (p < 0.001), receiving good advice (p = 0.001), fullness of orbit (p = 0.001), size (p = 0.007), direction of gaze relative to the healthy fellow eye (p = 0.005), eye lid contour (p = 0.037), comfort of the prosthetic eye (p < 0.001), colour relative to the healthy fellow eye (p < 0.001), and retention of the prosthetic eye (p < 0.001). Concerns about watering, crusting, discharge, visual perception, appearance, movement of the prosthetic eye, and health of the remaining eye were not significantly different between both groups. The results of this study showed that many general and specific levels of concern were significantly lower for cryolite glass prosthetic eye wearers than for PMMA prosthetic eye wearers. The question of why there are significant differences and to what extent the material of the prosthesis (cryolite glass or PMMA) has an impact on various concerns remains unanswered and should be addressed in a prospective comparative multicentre trial.

Major lower limb amputations in the Marshall Islands: incidence, prosthetic prescription, and prosthetic use after 6-18 months.

PubMed

Harding, Katherine

2005-03-01

The Republic of the Marshall Islands has been recognised anecdotally to have high rates of major lower limb amputations secondary to diabetes. During 2001, a prosthetics service was introduced as part of the rehabilitation service at Majuro Hospital. 1. To determine the incidence of major lower limb amputations over a one year period from 2002 to 2003. 2. To evaluate the proportion of patients suitable for prosthetic fitting. 3. Determine survival rates and usage of prostheses six to eighteen months after prosthetic fitting. Amputation rates were established through review of the surgical logs at the two hospitals in the Marshall Islands. Prosthetic fitting rates were determined using records from Majuro hospital rehabilitation service. Follow up interviews were conducted with fifteen surviving patients who received prostheses during the study period, to investigate prosthetic use. The incidence of major lower limb amputation was found to be 79.5 per 100,000 population, with all forty-five amputations being associated with diabetes. Just over a third of these patients were discharged from rehabilitation with a prosthesis. Fifteen of the patients were followed up post discharge. All of the thirteen with transtibial amputations were found to be using their prosthesis at least some of the day. The two patients with transfemoral amputations had ceased to walk with their prosthesis. This study identified a very high rate of lower limb amputation in the Marshall Islands by world standards. Prosthetic fitting rates and follow up results were comparable to those reported by others, and indicate that small, geographically isolated island nations such as the Marshall Islands are able to provide a successful prosthetics and rehabilitation service locally.

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

PubMed

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.

Systematic review of effects of current transtibial prosthetic socket designs--Part 2: Quantitative outcomes.

PubMed

Safari, Mohammad Reza; Meier, Margrit Regula

2015-01-01

This review is an attempt to untangle the complexity of transtibial prosthetic socket fit and perhaps find some indication of whether a particular prosthetic socket type might be best for a given situation. In addition, we identified knowledge gaps, thus providing direction for possible future research. We followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, using medical subject headings and standard key words to search for articles in relevant databases. No restrictions were made on study design and type of outcome measure used. From the obtained search results (n = 1,863), 35 articles were included. The relevant data were entered into a predefined data form that included the Downs and Black risk of bias assessment checklist. This article presents the results from the systematic review of the quantitative outcomes (n = 27 articles). Trends indicate that vacuum-assisted suction sockets improve gait symmetry, volume control, and residual limb health more than other socket designs. Hydrostatic sockets seem to create less inconsistent socket fittings, reducing a problem that greatly influences outcome measures. Knowledge gaps exist in the understanding of clinically meaningful changes in socket fit and its effect on biomechanical outcomes. Further, safe and comfortable pressure thresholds under various conditions should be determined through a systematic approach.

Development of a model osseo-magnetic link for intuitive rotational control of upper-limb prostheses.

PubMed

Rouse, Elliott J; Nahlik, David C; Peshkin, Michael A; Kuiken, Todd A

2011-04-01

The lack of proprioceptive feedback is a serious deficiency of current prosthetic control systems. The Osseo-Magnetic Link (OML) is a novel humeral or wrist rotation control system that could preserve proprioception. It utilizes a magnet implanted within the residual bone and sensors mounted in the prosthetic socket to detect magnetic field vectors and determine the bone's orientation. This allows the use of volitional bone rotation to control a prosthetic rotator. We evaluated the performance of the OML using a physical model of a transhumeral residual limb. A small Neodymium-Iron-Boron magnet was placed in a model humerus, inside a model upper arm. Four three-axis Hall-effect sensors were mounted on a ring 3 cm distal to the magnet. An optimization algorithm based on Newton's method determined the position and orientation of the magnet within the model humerus under various conditions, including bone translations, interference, and magnet misalignment. The orientation of the model humerus was determined within 3° for rotations centered in the arm; an additional 6° error was found for translations 20 mm from center. Adjustments in sensor placement may reduce these errors. The results demonstrate that the OML is a feasible solution for providing prosthesis rotation control while preserving rotational proprioception.

Rapid synthesis of maleimide functionalized fluorine-18 labeled prosthetic group using "radio-fluorination on the Sep-Pak" method.

PubMed

Basuli, Falguni; Zhang, Xiang; Jagoda, Elaine M; Choyke, Peter L; Swenson, Rolf E

2018-06-30

Following our recently published fluorine-18 labeling method, "Radio-fluorination on the Sep-Pak", we have successfully synthesized 6-[ 18 F]fluoronicotinaldehyde by passing a solution (1:4 acetonitrile: t-butanol) of its quaternary ammonium salt precursor, 6-(N,N,N-trimethylamino)nicotinaldehyde trifluoromethanesulfonate (2), through a fluorine-18 containing anion exchange cartridge (PS-HCO 3 ). Over 80% radiochemical conversion was observed using 10 mg of precursor within 1 minute. The [ 18 F]fluoronicotinaldehyde ([ 18 F]5) was then conjugated with 1-(6-(aminooxy)hexyl)-1H-pyrrole-2,5-dione to prepare the fluorine-18 labeled maleimide functionalized prosthetic group, 6-[ 18 F]fluoronicotinaldehyde O-(6-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)hexyl) oxime, 6-[ 18 F]FPyMHO ([ 18 F]6). The current Sep-Pak method not only improves the overall radiochemical yield (50 ± 9%, decay-corrected, n = 9) but also significantly reduces the synthesis time (from 60-90 minutes to 30 minutes) when compared with literature methods for the synthesis of similar prosthetic groups. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

Graft-Sparing Strategy for Thoracic Prosthetic Graft Infection.

PubMed

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.

Differences in the stress distribution in the distal femur between patellofemoral joint replacement and total knee replacement: a finite element study

PubMed Central

2012-01-01

Background Patellofemoral joint replacement is a successful treatment option for isolated patellofemoral osteoarthritis. However, results of later conversion to total knee replacement may be compromised by periprosthetic bone loss. Previous clinical studies have demonstrated a decrease in distal femoral bone mineral density after patellofemoral joint replacement. It is unclear whether this is due to periprosthetic stress shielding. The main objective of the current study was to evaluate the stress shielding effect of prosthetic replacement with 2 different patellofemoral prosthetic designs and with a total knee prosthesis. Methods We developed a finite element model of an intact patellofemoral joint, and finite element models of patellofemoral joint replacement with a Journey PFJ prosthesis, a Richards II prosthesis, and a Genesis II total knee prosthesis. For each of these 4 finite element models, the average Von Mises stress in 2 clinically relevant regions of interest were evaluated during a simulated squatting movement until 120 degrees of flexion. Results During deep knee flexion, in the anterior region of interest, the average Von Mises stress with the Journey PFJ design was comparable to the physiological knee, while reduced by almost 25% for both the Richards II design and the Genesis II total knee joint replacement design. The average Von Mises stress in the supracondylar region of interest was similar for both patellofemoral prosthetic designs and the physiological model, with slightly lower stress for the Genesis II design. Conclusions Patellofemoral joint replacement results in periprosthetic stress-shielding, although to a smaller degree than in total knee replacement. Specific patellofemoral prosthetic design properties may result in differences in femoral stress shielding. PMID:22704638

Use of the DEKA Arm for amputees with brachial plexus injury: A case series.

PubMed

Resnik, Linda; Fantini, Christopher; Latlief, Gail; Phillips, Samuel; Sasson, Nicole; Sepulveda, Eve

2017-01-01

Patients with upper limb amputation and brachial plexus injuries have high rates of prosthesis rejection. Study purpose is to describe experiences of subjects with transhumeral amputation and brachial plexus injury, who were fit with, and trained to use, a DEKA Arm. This was a mixed-methods study utilizing qualitative (e.g. interview, survey) and quantitative data (e.g. self-report and performance measures). Subject 1, a current prosthesis user, had a shoulder arthrodesis. Subject 2, not a prosthesis user, had a subluxed shoulder. Both were trained in laboratory and participated in a trial of home use. Descriptive analyses of processes and outcomes were conducted. Subject 1 was fitted with the transhumeral configuration (HC) DEKA Arm using a compression release stabilized socket. He had 12 hours of prosthetic training and participated in all home study activities. Subject 1 had improved dexterity and prosthetic satisfaction with the DEKA Arm and reported better quality of life (QOL) at the end of participation. Subject 2 was fit with the shoulder configuration (SC) DEKA Arm using a modified X-frame socket. He had 30 hours of training and participated in 3 weeks of home activities. He reported less functional disability at the end of training as compared to baseline, but encountered personal problems and exacerbation of PTSD symptoms and withdrew from home use portion at 3 weeks. Both subjects reported functional benefits from use, and expressed a desire to receive a DEKA Arm in the future. This paper reported on two different strategies for prosthetic fitting and their outcomes. The advantages and limitations of each approach were discussed. Use of both the HC and SC DEKA Arm for patients with TH amputation and brachial plexus injury was reported. Lessons learned may be instructive to clinicians considering prosthetic choices for future cases.

Interventions for Dental Implant Placement in Atrophic Edentulous Mandibles: Vertical Bone Augmentation and Alternative Treatments. A Meta-Analysis of Randomized Clinical Trials.

PubMed

Camps-Font, Octavi; Burgueño-Barris, Genís; Figueiredo, Rui; Jung, Ronald E; Gay-Escoda, Cosme; Valmaseda-Castellón, Eduard

2016-12-01

The purpose of the current study is to assess which vertical bone augmentation techniques are most effective for restoring atrophic posterior areas of the mandible with dental implants and compare these procedures with alternative treatments. Electronic literature searches in PubMed (MEDLINE), Ovid, and the Cochrane Library were conducted to identify all relevant articles published up to July 1, 2015. Eligibility was based on inclusion criteria, and quality assessments were conducted. The primary outcome variables were implant and prosthetic failure. After data extraction, meta-analyses were performed. Out of 527 potentially eligible papers, 14 randomized clinical trials were included. Out of these 14 studies, four trials assessed short implants (5 to 8 mm) as an alternative to vertical bone augmentation in sites with a residual ridge height of 5 to 8 mm. No statistically significant differences were found in implant (odds ratio [OR]: 1.02; 95% confidence interval [CI]: 0.31 to 3.31; P = 0.98; I 2 : 0%) or prosthetic failure (OR: 0.64; 95% CI: 0.21 to 1.96; P = 0.43; I 2 : 0%) after 12 months of loading. However, complications at treated sites increased with the augmentation procedures (OR: 8.33; 95% CI: 3.85 to 20.0; P <0.001; I 2 : 0%). There was no evidence of any vertical augmentation procedure being of greater benefit than any other for the primary outcomes (implant and prosthetic failure). Short implants in the posterior area of the mandible seem to be preferable to vertical augmentation procedures, which present similar implant and prosthetic failure rates but greater morbidity. All the vertical augmentation technique comparisons showed similar intergroup results.

Current trends and outcomes of breast reconstruction following nipple-sparing mastectomy: results from a national multicentric registry with 1006 cases over a 6-year period.

PubMed

Casella, Donato; Calabrese, Claudio; Orzalesi, Lorenzo; Gaggelli, Ilaria; Cecconi, Lorenzo; Santi, Caterina; Murgo, Roberto; Rinaldi, Stefano; Regolo, Lea; Amanti, Claudio; Roncella, Manuela; Serra, Margherita; Meneghini, Graziano; Bortolini, Massimiliano; Altomare, Vittorio; Cabula, Carlo; Catalano, Francesca; Cirilli, Alfredo; Caruso, Francesco; Lazzaretti, Maria Grazia; Meattini, Icro; Livi, Lorenzo; Cataliotti, Luigi; Bernini, Marco

2017-05-01

Reconstruction options following nipple-sparing mastectomy (NSM) are diverse and not yet investigated with level IA evidence. The analysis of surgical and oncological outcomes of NSM from the Italian National Registry shows its safety and wide acceptance both for prophylactic and therapeutic cases. A further in-depth analysis of the reconstructive approaches with their trend over time and their failures is the aim of this study. Data extraction from the National Database was performed restricting cases to the 2009-2014 period. Different reconstruction procedures were analyzed in terms of their distribution over time and with respect to specific indications. A 1-year minimum follow-up was conducted to assess reconstructive unsuccessful events. Univariate and multivariate analyses were performed to investigate the causes of both prosthetic and autologous failures. 913 patients, for a total of 1006 procedures, are included in the analysis. A prosthetic only reconstruction is accomplished in 92.2 % of cases, while pure autologous tissues are employed in 4.2 % and a hybrid (prosthetic plus autologous) in 3.6 %. Direct-to-implant (DTI) reaches 48.7 % of all reconstructions in the year 2014. Prophylactic NSMs have a DTI reconstruction in 35.6 % of cases and an autologous tissue flap in 12.9 % of cases. Failures are 2.7 % overall: 0 % in pure autologous flaps and 9.1 % in hybrid cases. Significant risk factors for failures are diabetes and the previous radiation therapy on the operated breast. Reconstruction following NSM is mostly prosthetic in Italy, with DTI gaining large acceptance over time. Failures are low and occurring in diabetic and irradiated patients at the multivariate analysis.

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

PubMed

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.

Attenuation of centre-of-pressure trajectory fluctuations under the prosthetic foot when using an articulating hydraulic ankle attachment compared to fixed attachment.

PubMed

De Asha, Alan R; Johnson, Louise; Munjal, Ramesh; Kulkarni, Jai; Buckley, John G

2013-02-01

Disruptions to the progress of the centre-of-pressure trajectory beneath prosthetic feet have been reported previously. These disruptions reflect how body weight is transferred over the prosthetic limb and are governed by the compliance of the prosthetic foot device and its ability to simulate ankle function. This study investigated whether using an articulating hydraulic ankle attachment attenuates centre-of-pressure trajectory fluctuations under the prosthetic foot compared to a fixed attachment. Twenty active unilateral trans-tibial amputees completed walking trials at their freely-selected, comfortable walking speed using both their habitual foot with either a rigid or elastic articulating attachment and a foot with a hydraulic ankle attachment. Centre-of-pressure displacement and velocity fluctuations beneath the prosthetic foot, prosthetic shank angular velocity during stance, and walking speed were compared between foot conditions. Use of the hydraulic device eliminated or reduced the magnitude of posteriorly directed centre-of-pressure displacements, reduced centre-of-pressure velocity variability across single-support, increased mean forward angular velocity of the shank during early stance, and increased freely chosen comfortable walking speed (P ≤ 0.002). The attenuation of centre-of-pressure trajectory fluctuations when using the hydraulic device indicated bodyweight was transferred onto the prosthetic limb in a smoother, less faltering manner which allowed the centre of mass to translate more quickly over the foot. Copyright © 2012 Elsevier Ltd. All rights reserved.

Human prosthetic joint infections are associated with myeloid-derived suppressor cells (MDSCs): Implications for infection persistence.

PubMed

Heim, Cortney E; Vidlak, Debbie; Odvody, Jessica; Hartman, Curtis W; Garvin, Kevin L; Kielian, Tammy

2017-11-15

Prosthetic joint infection (PJI) is a devastating complication of joint arthroplasty surgery typified by biofilm formation. Currently, mechanisms whereby biofilms persist and evade immune-mediated clearance in immune competent patients remain largely ill-defined. Therefore, the current study characterized leukocyte infiltrates and inflammatory mediator expression in tissues from patients with PJI compared to aseptic loosening. CD33 + HLA-DR - CD66b + CD14 -/low granulocytic myeloid-derived suppressor cells (G-MDSCs) were the predominant leukocyte population at sites of human PJI compared to aseptic tissues. MDSCs inhibit T cell proliferation, which coincided with reduced T cells in PJIs compared to aseptic tissues. IL-10, IL-6, and CXCL1 were significantly elevated in PJI tissues and have been implicated in MDSC inhibitory activity, expansion, and recruitment, respectively, which may account for their preferential increase in PJIs. This bias towards G-MDSC accumulation during human PJI could account for the chronicity of these infections by preventing the pro-inflammatory, antimicrobial actions of immune effector cells. Animal models of PJI have revealed a critical role for MDSCs and IL-10 in promoting infection persistence; however, whether this population is prevalent during human PJI and across distinct bacterial pathogens remains unknown. This study has identified that granulocytic-MDSC infiltrates are unique to human PJIs caused by distinct bacteria, which are not associated with aseptic loosening of prosthetic joints. Better defining the immune status of human PJIs could lead to novel immune-mediated approaches to facilitate PJI clearance in combination with conventional antibiotics. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

21 CFR 890.3420 - External limb prosthetic component.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false External limb prosthetic component. 890.3420 Section 890.3420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3420...

21 CFR 890.3025 - Prosthetic and orthotic accessory.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Prosthetic and orthotic accessory. 890.3025 Section 890.3025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025...

21 CFR 890.3025 - Prosthetic and orthotic accessory.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Prosthetic and orthotic accessory. 890.3025 Section 890.3025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025...

21 CFR 890.3025 - Prosthetic and orthotic accessory.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Prosthetic and orthotic accessory. 890.3025 Section 890.3025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025...

21 CFR 890.3420 - External limb prosthetic component.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false External limb prosthetic component. 890.3420 Section 890.3420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3420...

21 CFR 890.3420 - External limb prosthetic component.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External limb prosthetic component. 890.3420 Section 890.3420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3420...

21 CFR 890.3025 - Prosthetic and orthotic accessory.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Prosthetic and orthotic accessory. 890.3025 Section 890.3025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025...

21 CFR 890.3420 - External limb prosthetic component.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false External limb prosthetic component. 890.3420 Section 890.3420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3420...

21 CFR 890.3420 - External limb prosthetic component.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false External limb prosthetic component. 890.3420 Section 890.3420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3420...

21 CFR 890.3025 - Prosthetic and orthotic accessory.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prosthetic and orthotic accessory. 890.3025 Section 890.3025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025...

Patient Management with Metallic Valve Prosthesis during Pregnancy and Postpartum Period.

PubMed

Garcez, Juliane Dantas Seabra; Rosa, Vitor Emer Egypto; Lopes, Antonio Sergio de Santis Andrade; Accorsi, Tarso Augusto Duenhas; Fernandes, João Ricardo Cordeiro; Pomerantzeff, Pablo Maria; Avila, Walkiria Samuel; Tarasoutchi, Flavio

2015-10-01

Prosthetic thrombosis is a rare complication, but it has high mortality and morbidity. Young women of childbearing age that have prosthetic heart valves are at increased risk of thrombosis during pregnancy due to changes in coagulation factors. Anticoagulation with adequate control and frequent follow-up if pregnancy occurs must be performed in order to prevent complications related to anticoagulant use. Surgery remains the treatment of choice for prosthetic heart valve thrombosis in most clinical conditions. Patients with metallic prosthetic valves have an estimated 5% risk of thrombosis during pregnancy and maternal mortality of 1.5% related to the event. Anticoagulation with vitamin K antagonists during pregnancy is related to varying degrees of complications at each stage of the pregnancy and postpartum periods. Warfarin sodium crosses the placental barrier and when used in the first trimester of pregnancy is a teratogenic agent, causing 1-3% of malformations characterized by fetal warfarin syndrome and also constitutes a major cause of miscarriage in 10-30% of cases. In the third trimester and at delivery, the use of warfarin is associated with maternal and neonatal bleeding in approximately 5 to 15% of cases, respectively. On the other hand, inadequate anticoagulation, including the suspension of the oral anticoagulants aiming at fetal protection, carries a maternal risk of about 25% of metallic prosthesis thrombosis, particularly in the mitral valve. This fact is also due to the state of maternal hypercoagulability with activation of coagulation factors V, VI, VII, IX, X, platelet activity and fibrinogen synthesis, and decrease in protein S levels. The Registry of Pregnancy and Cardiac Disease (ROPAC), assessing 212 pregnant women with metal prosthesis, showed that prosthesis thrombosis occurred in 10 (4.7%) patients and maternal hemorrhage in 23.1%, concluding that only 58% of patients with metallic prosthesis had a complication-free pregnancy.

Improved prosthetic hand control with concurrent use of myoelectric and inertial measurements.

PubMed

Krasoulis, Agamemnon; Kyranou, Iris; Erden, Mustapha Suphi; Nazarpour, Kianoush; Vijayakumar, Sethu

2017-07-11

Myoelectric pattern recognition systems can decode movement intention to drive upper-limb prostheses. Despite recent advances in academic research, the commercial adoption of such systems remains low. This limitation is mainly due to the lack of classification robustness and a simultaneous requirement for a large number of electromyogram (EMG) electrodes. We propose to address these two issues by using a multi-modal approach which combines surface electromyography (sEMG) with inertial measurements (IMs) and an appropriate training data collection paradigm. We demonstrate that this can significantly improve classification performance as compared to conventional techniques exclusively based on sEMG signals. We collected and analyzed a large dataset comprising recordings with 20 able-bodied and two amputee participants executing 40 movements. Additionally, we conducted a novel real-time prosthetic hand control experiment with 11 able-bodied subjects and an amputee by using a state-of-the-art commercial prosthetic hand. A systematic performance comparison was carried out to investigate the potential benefit of incorporating IMs in prosthetic hand control. The inclusion of IM data improved performance significantly, by increasing classification accuracy (CA) in the offline analysis and improving completion rates (CRs) in the real-time experiment. Our findings were consistent across able-bodied and amputee subjects. Integrating the sEMG electrodes and IM sensors within a single sensor package enabled us to achieve high-level performance by using on average 4-6 sensors. The results from our experiments suggest that IMs can form an excellent complimentary source signal for upper-limb myoelectric prostheses. We trust that multi-modal control solutions have the potential of improving the usability of upper-extremity prostheses in real-life applications.

Agonist-antagonist active knee prosthesis: a preliminary study in level-ground walking.

PubMed

Martinez-Villalpando, Ernesto C; Herr, Hugh

2009-01-01

We present a powered knee prosthesis with two series-elastic actuators positioned in parallel in an agonist-antagonist arrangement. To motivate the knee's design, we developed a prosthetic knee model that comprises a variable damper and two series-elastic clutch units that span the knee joint. Using human gait data to constrain the model's joint to move biologically, we varied model parameters using an optimization scheme that minimized the sum over time of the squared difference between the model's joint torque and biological knee values. We then used these optimized values to specify the mechanical and control design of the prosthesis for level-ground walking. We hypothesized that a variable-impedance control design could produce humanlike knee mechanics during steady-state level-ground walking. As a preliminary evaluation of this hypothesis, we compared the prosthetic knee mechanics of an amputee walking at a self-selected gait speed with those of a weight- and height-matched nonamputee. We found qualitative agreement between prosthetic and human knee mechanics. Because the knee's motors never perform positive work on the knee joint throughout the level-ground gait cycle, the knee's electrical power requirement is modest in walking (8 W), decreasing the size of the onboard battery required to power the prosthesis.

Evaluation of a Powered Ankle-Foot Prosthesis during Slope Ascent Gait

PubMed Central

2016-01-01

Passive prosthetic feet lack active plantarflexion and push-off power resulting in gait deviations and compensations by individuals with transtibial amputation (TTA) during slope ascent. We sought to determine the effect of active ankle plantarflexion and push-off power provided by a powered prosthetic ankle-foot (PWR) on lower extremity compensations in individuals with unilateral TTA as they walked up a slope. We hypothesized that increased ankle plantarflexion and push-off power would reduce compensations commonly observed with a passive, energy-storing-returning prosthetic ankle-foot (ESR). We compared the temporal spatial, kinematic, and kinetic measures of ten individuals with TTA (age: 30.2 ± 5.3 yrs) to matched abled-bodied (AB) individuals during 5° slope ascent. The TTA group walked with an ESR and separately with a PWR. The PWR produced significantly greater prosthetic ankle plantarflexion and push-off power generation compared to an ESR and more closely matched AB values. The PWR functioned similar to a passive ESR device when transitioning onto the prosthetic limb due to limited prosthetic dorsiflexion, which resulted in similar deviations and compensations. In contrast, when transitioning off the prosthetic limb, increased ankle plantarflexion and push-off power provided by the PWR contributed to decreased intact limb knee extensor power production, lessening demand on the intact limb knee. PMID:27977681

Evaluation of a Powered Ankle-Foot Prosthesis during Slope Ascent Gait.

PubMed

Rábago, Christopher A; Aldridge Whitehead, Jennifer; Wilken, Jason M

2016-01-01

Passive prosthetic feet lack active plantarflexion and push-off power resulting in gait deviations and compensations by individuals with transtibial amputation (TTA) during slope ascent. We sought to determine the effect of active ankle plantarflexion and push-off power provided by a powered prosthetic ankle-foot (PWR) on lower extremity compensations in individuals with unilateral TTA as they walked up a slope. We hypothesized that increased ankle plantarflexion and push-off power would reduce compensations commonly observed with a passive, energy-storing-returning prosthetic ankle-foot (ESR). We compared the temporal spatial, kinematic, and kinetic measures of ten individuals with TTA (age: 30.2 ± 5.3 yrs) to matched abled-bodied (AB) individuals during 5° slope ascent. The TTA group walked with an ESR and separately with a PWR. The PWR produced significantly greater prosthetic ankle plantarflexion and push-off power generation compared to an ESR and more closely matched AB values. The PWR functioned similar to a passive ESR device when transitioning onto the prosthetic limb due to limited prosthetic dorsiflexion, which resulted in similar deviations and compensations. In contrast, when transitioning off the prosthetic limb, increased ankle plantarflexion and push-off power provided by the PWR contributed to decreased intact limb knee extensor power production, lessening demand on the intact limb knee.

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

PubMed Central

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

Increasing prosthetic foot energy return affects whole-body mechanics during walking on level ground and slopes.

PubMed

Childers, W Lee; Takahashi, Kota Z

2018-03-29

Prosthetic feet are designed to store energy during early stance and then release a portion of that energy during late stance. The usefulness of providing more energy return depends on whether or not that energy transfers up the lower limb to aid in whole body propulsion. This research examined how increasing prosthetic foot energy return affected walking mechanics across various slopes. Five people with a uni-lateral transtibial amputation walked on an instrumented treadmill at 1.1 m/s for three conditions (level ground, +7.5°, -7.5°) while wearing a prosthetic foot with a novel linkage system and a traditional energy storage and return foot. The novel foot demonstrated greater range of motion (p = 0.0012), and returned more energy (p = 0.023) compared to the traditional foot. The increased energy correlated with an increase in center of mass (CoM) energy change during propulsion from the prosthetic limb (p = 0.012), and the increased prosthetic limb propulsion correlated to a decrease in CoM energy change (i.e., collision) on the sound limb (p < 0.001). These data indicate that this novel foot was able to return more energy than a traditional prosthetic foot and that this additional energy was used to increase whole body propulsion.

Biomechanics principle of elbow joint for transhumeral prostheses: comparison of normal hand, body-powered, myoelectric & air splint prostheses.

PubMed

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

2014-09-10

Understanding of kinematics force applied at the elbow is important in many fields, including biomechanics, biomedical engineering and rehabilitation. This paper provides a comparison of a mathematical model of elbow joint using three different types of prosthetics for transhumeral user, and characterizes the forces required to overcome the passive mechanical of the prosthetics at the residual limb. The study modeled the elbow as a universal joint with intersecting axes of x-axis and y-axis in a plain of upper arm and lower arm. The equations of force applied, torque, weight and length of different type of prosthetics and the anthropometry of prosthetics hand are discussed in this study. The study also compares the force, torque and pressure while using all three types of prosthetics with the normal hand. The result was measured from the elbow kinematics of seven amputees, using three different types of prosthetics. The F-Scan sensor used in the study is to determine the pressure applied at the residual limb while wearing different type of prostheses. These technological advances in assessment the biomechanics of an elbow joint for three different type of prosthetics with the normal hand bring the new information for the amputees and prosthetist to choose the most suitable device to be worn daily.

Feedforward control strategies of subjects with transradial amputation in planar reaching.

PubMed

Metzger, Anthony J; Dromerick, Alexander W; Schabowsky, Christopher N; Holley, Rahsaan J; Monroe, Brian; Lum, Peter S

2010-01-01

The rate of upper-limb amputations is increasing, and the rejection rate of prosthetic devices remains high. People with upper-limb amputation do not fully incorporate prosthetic devices into their activities of daily living. By understanding the reaching behaviors of prosthesis users, researchers can alter prosthetic devices and develop training protocols to improve the acceptance of prosthetic limbs. By observing the reaching characteristics of the nondisabled arms of people with amputation, we can begin to understand how the brain alters its motor commands after amputation. We asked subjects to perform rapid reaching movements to two targets with and without visual feedback. Subjects performed the tasks with both their prosthetic and nondisabled arms. We calculated endpoint error, trajectory error, and variability and compared them with those of nondisabled control subjects. We found no significant abnormalities in the prosthetic limb. However, we found an abnormal leftward trajectory error (in right arms) in the nondisabled arm of prosthetic users in the vision condition. In the no-vision condition, the nondisabled arm displayed abnormal leftward endpoint errors and abnormally higher endpoint variability. In the vision condition, peak velocity was lower and movement duration was longer in both arms of subjects with amputation. These abnormalities may reflect the cortical reorganization associated with limb loss.

Autologous alternative veins may not provide better outcomes than prosthetic conduits for below-knee bypass when great saphenous vein is unavailable.

PubMed

Avgerinos, Efthymios D; Sachdev, Ulka; Naddaf, Abdallah; Doucet, Dannielle R; Mohapatra, Abhisekh; Leers, Steven A; Chaer, Rabih A; Makaroun, Michel S

2015-08-01

There is a need to better define the role of alternative autologous vein (AAV) segments over contemporary prosthetic conduits in patients with critical limb ischemia when great saphenous vein (GSV) is not available for use as the bypass conduit. Consecutive patients who underwent bypass to infrageniculate targets between 2007 and 2011 were categorized in three groups: GSV, AAV, and prosthetic. The primary outcome was graft patency. The secondary outcome was limb salvage. Cox proportional hazards regression was used to adjust for baseline confounding variables. A total of 407 infrainguinal bypasses to below-knee targets were analyzed; 255 patients (63%) received a single-segment GSV, 106 patients (26%) received an AAV, and 46 patients (11%) received a prosthetic conduit. Baseline characteristics were similar among groups, with the exception of popliteal targets and anticoagulation use being more frequent in the prosthetic group. Primary patency at 2 and 5 years was estimated at 47% and 32%, respectively, for the GSV group; 24% and 23% for the AAV group; and 43% and 38% for the prosthetic group. Primary assisted patency at 2 and 5 years was estimated at 71% and 55%, respectively, for the GSV group; 53% and 51% for the AAV group; and 45% and 40% for the prosthetic group. Secondary patency at 2 and 5 years was estimated at 75% and 60%, respectively, for the GSV group; 57% and 55% for the AAV group; and 46% and 41% for the prosthetic group. In Cox analysis, primary patency (hazard ratio [HR], 0.55; P < .001; 95% confidence interval [CI], 0.404-0.758), primary assisted patency (HR, 0.57; P = .004; 95% CI, 0.388-0.831), and secondary patency (HR, 0.56; P = .005; 95% CI, 0.372-0.840) were predicted by GSV compared with AAV, but there was no difference between AAV and prosthetic grafts except for the primary patency, for which prosthetic was protective (HR, 0.38; P < .001; 95% CI, 0.224-0.629). Limb salvage was similar among groups. AAV conduits may not offer a significant patency advantage in midterm follow-up over prosthetic bypasses. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

The biological response to orthopedic implants for joint replacement. II: Polyethylene, ceramics, PMMA, and the foreign body reaction

PubMed Central

Gibon, Emmanuel; Córdova, Luis A.; Lu, Laura; Lin, Tzu-Hua; Yao, Zhenyu; Hamadouche, Moussa; Goodman, Stuart B.

2017-01-01

Novel evidence-based prosthetic designs and biomaterials facilitate the performance of highly successful joint replacement (JR) procedures. To achieve this goal, constructs must be durable, biomechanically sound, and avoid adverse local tissue reactions. Different biomaterials such as metals and their alloys, polymers, ceramics, and composites are currently used for JR implants. This review focuses on (1) the biological response to the different biomaterials used for TJR and (2) the chronic inflammatory and foreign-body response induced by byproducts of these biomaterials. A homeostatic state of bone and surrounding soft tissue with current biomaterials for JR can be achieved with mechanically stable, infection free and intact (as opposed to the release of particulate or ionic byproducts) implants. Adverse local tissue reactions (an acute/chronic inflammatory reaction, periprosthetic osteolysis, loosening and subsequent mechanical failure) may evolve when the latter conditions are not met. This article (Part 2 of 2) summarizes the biological response to the non-metallic materials commonly used for joint replacement including polyethylene, ceramics, and polymethylmethacrylate (PMMA), as well as the foreign body reaction to byproducts of these materials. PMID:27080740

Enhancement of a prosthetic knee with a microprocessor-controlled gait phase switch reduces falls and improves balance confidence and gait speed in community ambulators with unilateral transfemoral amputation.

PubMed

Fuenzalida Squella, Sara Agueda; Kannenberg, Andreas; Brandão Benetti, Ângelo

2018-04-01

Despite the evidence for improved safety and function of microprocessor stance and swing-controlled prosthetic knees, non-microprocessor-controlled prosthetic knees are still standard of care for persons with transfemoral amputations in most countries. Limited feature microprocessor-control enhancement of such knees could stand to significantly improve patient outcomes. To evaluate gait speed, balance, and fall reduction benefits of the new 3E80 default stance hydraulic knee compared to standard non-microprocessor-controlled prosthetic knees. Comparative within-subject clinical study. A total of 13 young, high-functioning community ambulators with a transfemoral amputation underwent assessment of performance-based (e.g. 2-min walk test, timed ramp/stair tests) and self-reported (e.g. falls, Activities-Specific Balance Confidence scale, Prosthesis Evaluation Questionnaire question #1, Satisfaction with the Prosthesis) outcome measures for their non-microprocessor-controlled prosthetic knees and again after 8 weeks of accommodation to the 3E80 microprocessor-enhanced knee. Self-reported falls significantly declined 77% ( p = .04), Activities-Specific Balance Confidence scores improved 12 points ( p = .005), 2-min walk test walking distance increased 20 m on level ( p = .01) and uneven ( p = .045) terrain, and patient satisfaction significantly improved ( p < .01) when using the 3E80 knee. Slope and stair ambulation performance did not differ between knee conditions. The 3E80 knee reduced self-reported fall incidents and improved balance confidence. Walking performance on both level and uneven terrains also improved compared to non-microprocessor-controlled prosthetic knees. Subjects' satisfaction was significantly higher than with their previous non-microprocessor-controlled prosthetic knees. The 3E80 may be considered a prosthetic option for improving gait performance, balance confidence, and safety in highly active amputees. Clinical relevance This study compared performance-based and self-reported outcome measures when using non-microprocessor and a new microprocessor-enhanced, default stance rotary hydraulic knee. The results inform rehabilitation professionals about the functional benefits of a limited-feature, microprocessor-enhanced hydraulic prosthetic knee over standard non-microprocessor-controlled prosthetic knees.

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

PubMed

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

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

PubMed Central

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.

2014-01-01

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. PMID:21708509

An evaluation of dental prosthetic status and prosthetic needs among eunuchs (trans genders) residing in bhopal city, madhya pradesh, India: a cross-sectional study.

PubMed

Hongal, S; Torwane, Na; Chandrashekhar, Br; Saxena, V; Chavan, Kr

2014-11-01

Eunuchs are considered as the most vulnerable, frustrated, and insecure community. The accessibility to medical and dental facilities for the eunuchs is nearly nonexistent. Due to these reasons, they might be at a high risk of developing severe dental problems like tooth loss. The present cross-sectional study aimed to evaluate the dental prosthetic status and prosthetic needs among eunuchs residing in Bhopal city, Madhya Pradesh, India. On the basis of convenient nonprobability snowball sampling technique, all the self-identified eunuchs residing in the city of Bhopal along with a matched control consisting of cross section of the general population residing in the same locality was examined to evaluate the prosthetic status and prosthetic needs of the population. All the obtained data were entered into a personal computer on Microsoft excel sheet and analyzed using the software; Statistical Package for Social Science version 20. Data comparison was done by applying Chi-square test. A total of 639 subjects comprised of 207 eunuchs, 218 males and 214 females. Among all participants, 2.8% (18/639) were having prosthesis. The overall prosthetic status among males was 3.2% (7/218) followed by 2.9% (6/207) eunuchs and 2.3% (5/214) females. However, need for multi-unit and combination of one and more unit prosthesis for upper and lower jaws was higher in males compared to females and eunuchs, but the difference was not statistically significant. The findings of this study clearly demonstrate a high unmet need for prosthetic care among the population surveyed.

Interactions of Prosthetic and Natural Vision in Animals With Local Retinal Degeneration

PubMed Central

Lorach, Henri; Lei, Xin; Galambos, Ludwig; Kamins, Theodore; Mathieson, Keith; Dalal, Roopa; Huie, Philip; Harris, James; Palanker, Daniel

2015-01-01

Purpose Prosthetic restoration of partial sensory loss leads to interactions between artificial and natural inputs. Ideally, the rehabilitation should allow perceptual fusion of the two modalities. Here we studied the interactions between normal and prosthetic vision in a rodent model of local retinal degeneration. Methods Implantation of a photovoltaic array in the subretinal space of normally sighted rats induced local degeneration of the photoreceptors above the chip, and the inner retinal neurons in this area were electrically stimulated by the photovoltaic implant powered by near-infrared (NIR) light. We studied prosthetic and natural visually evoked potentials (VEP) in response to simultaneous stimulation by NIR and visible light patterns. Results We demonstrate that electrical and natural VEPs summed linearly in the visual cortex, and both responses decreased under brighter ambient light. Responses to visible light flashes increased over 3 orders of magnitude of contrast (flash/background), while for electrical stimulation the contrast range was limited to 1 order of magnitude. The maximum amplitude of the prosthetic VEP was three times lower than the maximum response to a visible flash over the same area on the retina. Conclusions Ambient light affects prosthetic responses, albeit much less than responses to visible stimuli. Prosthetic representation of contrast in the visual scene can be encoded, to a limited extent, by the appropriately calibrated stimulus intensity, which also depends on the ambient light conditions. Such calibration will be important for patients combining central prosthetic vision with natural peripheral sight, such as in age-related macular degeneration. PMID:26618643

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

PubMed

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 (P<0.05). Prosthetic MV pannus 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.

Dynamic tracking of prosthetic valve motion and deformation from bi-plane x-ray views: feasibility study

NASA Astrophysics Data System (ADS)

Hatt, Charles R.; Wagner, Martin; Raval, Amish N.; Speidel, Michael A.

2016-03-01

Transcatheter aortic valve replacement (TAVR) requires navigation and deployment of a prosthetic valve within the aortic annulus under fluoroscopic guidance. To support improved device visualization in this procedure, this study investigates the feasibility of frame-by-frame 3D reconstruction of a moving and expanding prosthetic valve structure from simultaneous bi-plane x-ray views. In the proposed method, a dynamic 3D model of the valve is used in a 2D/3D registration framework to obtain a reconstruction of the valve. For each frame, valve model parameters describing position, orientation, expansion state, and deformation are iteratively adjusted until forward projections of the model match both bi-plane views. Simulated bi-plane imaging of a valve at different signal-difference-to-noise ratio (SDNR) levels was performed to test the approach. 20 image sequences with 50 frames of valve deployment were simulated at each SDNR. The simulation achieved a target registration error (TRE) of the estimated valve model of 0.93 +/- 2.6 mm (mean +/- S.D.) for the lowest SDNR of 2. For higher SDNRs (5 to 50) a TRE of 0.04 mm +/- 0.23 mm was achieved. A tabletop phantom study was then conducted using a TAVR valve. The dynamic 3D model was constructed from high resolution CT scans and a simple expansion model. TRE was 1.22 +/- 0.35 mm for expansion states varying from undeployed to fully deployed, and for moderate amounts of inter-frame motion. Results indicate that it is feasible to use bi-plane imaging to recover the 3D structure of deformable catheter devices.

Dynamic tracking of prosthetic valve motion and deformation from bi-plane x-ray views: feasibility study.

PubMed

Hatt, Charles R; Wagner, Martin; Raval, Amish N; Speidel, Michael A

2016-01-01

Transcatheter aortic valve replacement (TAVR) requires navigation and deployment of a prosthetic valve within the aortic annulus under fluoroscopic guidance. To support improved device visualization in this procedure, this study investigates the feasibility of frame-by-frame 3D reconstruction of a moving and expanding prosthetic valve structure from simultaneous bi-plane x-ray views. In the proposed method, a dynamic 3D model of the valve is used in a 2D/3D registration framework to obtain a reconstruction of the valve. For each frame, valve model parameters describing position, orientation, expansion state, and deformation are iteratively adjusted until forward projections of the model match both bi-plane views. Simulated bi-plane imaging of a valve at different signal-difference-to-noise ratio (SDNR) levels was performed to test the approach. 20 image sequences with 50 frames of valve deployment were simulated at each SDNR. The simulation achieved a target registration error (TRE) of the estimated valve model of 0.93 ± 2.6 mm (mean ± S.D.) for the lowest SDNR of 2. For higher SDNRs (5 to 50) a TRE of 0.04 mm ± 0.23 mm was achieved. A tabletop phantom study was then conducted using a TAVR valve. The dynamic 3D model was constructed from high resolution CT scans and a simple expansion model. TRE was 1.22 ± 0.35 mm for expansion states varying from undeployed to fully deployed, and for moderate amounts of inter-frame motion. Results indicate that it is feasible to use bi-plane imaging to recover the 3D structure of deformable catheter devices.

21 CFR 870.3935 - Prosthetic heart valve holder.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prosthetic heart valve holder. 870.3935 Section... heart valve holder. (a) Identification. A prosthetic heart valve holder is a device used to hold a replacement heart valve while it is being sutured into place. (b) Classification. Class I. The device is...

21 CFR 870.3935 - Prosthetic heart valve holder.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Prosthetic heart valve holder. 870.3935 Section... heart valve holder. (a) Identification. A prosthetic heart valve holder is a device used to hold a replacement heart valve while it is being sutured into place. (b) Classification. Class I. The device is...

21 CFR 870.3935 - Prosthetic heart valve holder.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Prosthetic heart valve holder. 870.3935 Section... heart valve holder. (a) Identification. A prosthetic heart valve holder is a device used to hold a replacement heart valve while it is being sutured into place. (b) Classification. Class I. The device is...

21 CFR 870.3935 - Prosthetic heart valve holder.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Prosthetic heart valve holder. 870.3935 Section... heart valve holder. (a) Identification. A prosthetic heart valve holder is a device used to hold a replacement heart valve while it is being sutured into place. (b) Classification. Class I. The device is...

21 CFR 870.3935 - Prosthetic heart valve holder.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Prosthetic heart valve holder. 870.3935 Section... heart valve holder. (a) Identification. A prosthetic heart valve holder is a device used to hold a replacement heart valve while it is being sutured into place. (b) Classification. Class I. The device is...

75 FR 9480 - Qualification of Drivers; Exemption Applications; Vision

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-02

.... Buchanan, 56, has a prosthetic left eye due to a traumatic injury sustained in 1961. The best corrected... prosthetic right eye due to a traumatic injury sustained at age 12. The best corrected visual acuity in his..., has a prosthetic left eye due to a traumatic injury sustained during childhood. The best corrected...

Options in virtual 3D, optical-impression-based planning of dental implants.

PubMed

Reich, Sven; Kern, Thomas; Ritter, Lutz

2014-01-01

If a 3D radiograph, which in today's dentistry often consists of a CBCT dataset, is available for computerized implant planning, the 3D planning should also consider functional prosthetic aspects. In a conventional workflow, the CBCT is done with a specially produced radiopaque prosthetic setup that makes the desired prosthetic situation visible during virtual implant planning. If an exclusively digital workflow is chosen, intraoral digital impressions are taken. On these digital models, the desired prosthetic suprastructures are designed. The entire datasets are virtually superimposed by a "registration" process on the corresponding structures (teeth) in the CBCTs. Thus, both the osseous and prosthetic structures are visible in one single 3D application and make it possible to consider surgical and prosthetic aspects. After having determined the implant positions on the computer screen, a drilling template is designed digitally. According to this design (CAD), a template is printed or milled in CAM process. This template is the first physically extant product in the entire workflow. The article discusses the options and limitations of this workflow.

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

PubMed

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.

Upper extremity limb loss: functional restoration from prosthesis and targeted reinnervation to transplantation.

PubMed

Carlsen, Brian T; Prigge, Pat; Peterson, Jennifer

2014-01-01

For several decades, prosthetic use was the only option to restore function after upper extremity amputation. Recent years have seen advances in the field of prosthetics. Such advances include prosthetic design and function, activity-specific devices, improved aesthetics, and adjunctive surgical procedures to improve both form and function. Targeted reinnervation is one exciting advance that allows for more facile and more intuitive function with prosthetics following proximal amputation. Another remarkable advance that holds great promise in nearly all fields of medicine is the transplantation of composite tissue, such as hand and face transplantation. Hand transplantation holds promise as the ultimate restorative procedure that can provide form, function, and sensation. However, this procedure still comes with a substantial cost in terms of the rehabilitation and toxic immunosuppression and should be limited to carefully selected patients who have failed prosthetic reconstruction. Hand transplantation and prosthetic reconstruction should not be viewed as competing options. Rather, they are two treatment options with different risk/benefit profiles and different indications and, hence vastly different implications. Copyright © 2014 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

Pannus-related prosthetic valve dysfunction. Case report

PubMed Central

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. PMID:27004041

Pannus-related prosthetic valve dysfunction. Case report.

PubMed

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.

Hydrodynamic endurance test of the prosthetic valve used in the various types of the ventricular assist device.

PubMed

Nitta, S; Yambe, T; Katahira, Y; Sonobe, T; Saijoh, Y; Naganuma, S; Akiho, H; Kakinuma, Y; Tanaka, M; Miura, M

1991-12-01

To evaluate the various basic designs of the pump chambers used in the ventricular assist devices (VADs), hydrodynamic endurance test was performed from the viewpoint of the durability of the prosthetic valves used in the VAD. For the hydrodynamic analysis, we designed three basic types of pump (sac type, diaphragm type, and pusher plate type) using the same material and having the same capacity and shape. Prosthetic valves in these VADs were tested from the standpoint of the water hammer effect, which affects the valve durability, to determine which pump design would be most durable as a prosthetic valve in the VAD. The water-hammer phenomenon was evaluated using the maximum pressure gradient (MPG) across the prosthetic valve in the moc circulatory loop. Maximum pump output was recorded when we used the diaphragm type model, and minimum MPG in the commonly used driving condition of the VAD were recorded when we used the sac type model. The results suggest that the sac type VAD model is the most durable design for the prosthetic value.

Will Regulatory and Financial Considerations Dampen Innovation in the Clinical Microbiology Laboratory?

PubMed

Gilligan, Peter H; Miller, Melissa B

2016-02-02

Over a million prosthetic joints are placed in patients in the United States annually. Of those that fail, 25% will be due to infection, with an estimated cost approaching 1 billion dollars. Despite the clinical and economic importance of these infections, the techniques for their detection are relatively insensitive. An innovative method for detecting these infections by using blood culture bottles (BCB) to culture specimens of periprosthetic tissue (PPT) was described in a recent article [T. N. Peel, et al., mBio 7(1):e01776-15, 2016, doi:10.1128/mBio.01776-15]. There are two potential stumbling blocks to the widespread implementation of this innovation. First, the FDA judges such an application of BCB as an "off-label use" and as such, a laboratory-developed test (LDT). LDTs are coming under greater scrutiny by the FDA and may require extensive, costly validation studies in laboratories that adopt this methodology. Second, the Center for Medicare and Medicaid Services has established a Hospital Acquired Condition Reduction Act under which institutions performing in the lowest quartile forfeit 1% of their Medicare reimbursement. Hospital-acquired infections are an important component of this quality metric. Although prosthetic joint infection (PJI) rates are not currently a hospital quality metric, given their cost and increasing frequency, it is reasonable to expect that they may become one. Will those with financial oversight allow an innovative technique that will require an expensive validation and may put the institution at risk for loss of CMS reimbursement? Copyright © 2016 Gilligan and Miller.

Popliteal Artery Repair in Massively Transfused Military Trauma Casualties: A Pursuit to Save Life and Limb

DTIC Science & Technology

2010-07-01

were centrally scored and calculated by trained re- search nurses and staff using ISS-98 after patient discharge. A Level I facility was defined as a...casualties, once evacuated to the United States, had limited remaining autogenous vein and required prosthetic grafts in the secondary management of failed

Rehand: Realistic electric prosthetic hand created with a 3D printer.

PubMed

Yoshikawa, Masahiro; Sato, Ryo; Higashihara, Takanori; Ogasawara, Tsukasa; Kawashima, Noritaka

2015-01-01

Myoelectric prosthetic hands provide an appearance with five fingers and a grasping function to forearm amputees. However, they have problems in weight, appearance, and cost. This paper reports on the Rehand, a realistic electric prosthetic hand created with a 3D printer. It provides a realistic appearance that is same as the cosmetic prosthetic hand and a grasping function. A simple link mechanism with one linear actuator for grasping and 3D printed parts achieve low cost, light weight, and ease of maintenance. An operating system based on a distance sensor provides a natural operability equivalent to the myoelectric control system. A supporter socket allows them to wear the prosthetic hand easily. An evaluation using the Southampton Hand Assessment Procedure (SHAP) demonstrated that an amputee was able to operate various objects and do everyday activities with the Rehand.

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

PubMed

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.

Progressive upper limb prosthetics.

PubMed

Lake, Chris; Dodson, Robert

2006-02-01

The field of upper extremity prosthetics is a constantly changing arena as researchers and prosthetists strive to bridge the gap between prosthetic reality and upper limb physiology. With the further development of implantable neurologic sensing devices and targeted muscle innervation (discussed elsewhere in this issue), the challenge of limited input to control vast outputs promises to become a historical footnote in the future annals of upper limb prosthetics. Soon multidextrous terminal devices, such as that found in the iLimb system(Touch EMAS, Inc., Edinburgh, UK), will be a clinical reality (Fig. 22). Successful prosthetic care depends on good communication and cooperation among the surgeon, the amputee, the rehabilitation team, and the scientists harnessing the power of technology to solve real-life challenges. If the progress to date is any indication, amputees of the future will find their dreams limited only by their imagination.

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

PubMed Central

El Fattah, Hisham; Zaghloul, Ashraf; Escuin, Tomas

2012-01-01

Objectives: 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. Study Design: 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). Results: 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. Conclusions: 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 surgery during maxillectomy and prosthodontic technique. Key words:Maxillectomy, pre-prosthetic surgery, quality of life, oral cancer. PMID:22143710

Extrinsic mechanism obstructing the opening of a prosthetic mitral valve: an unusual case of suture entrapment.

PubMed

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.

Offline decoding of end-point forces using neural ensembles: application to a brain-machine interface.

PubMed

Gupta, Rahul; Ashe, James

2009-06-01

Brain-machine interfaces (BMIs) hold a lot of promise for restoring some level of motor function to patients with neuronal disease or injury. Current BMI approaches fall into two broad categories--those that decode discrete properties of limb movement (such as movement direction and movement intent) and those that decode continuous variables (such as position and velocity). However, to enable the prosthetic devices to be useful for common everyday tasks, precise control of the forces applied by the end-point of the prosthesis (e.g., the hand) is also essential. Here, we used linear regression and Kalman filter methods to show that neural activity recorded from the motor cortex of the monkey during movements in a force field can be used to decode the end-point forces applied by the subject successfully and with high fidelity. Furthermore, the models exhibit some generalization to novel task conditions. We also demonstrate how the simultaneous prediction of kinematics and kinetics can be easily achieved using the same framework, without any degradation in decoding quality. Our results represent a useful extension of the current BMI technology, making dynamic control of a prosthetic device a distinct possibility in the near future.

Analysis of maxillofacial prosthetics at university dental hospitals in the capital region of Korea

PubMed Central

Lee, Jong-Ho

2016-01-01

PURPOSE The purpose of this study was to investigate the demographic patterns of maxillofacial prosthetic treatment to identify the characteristics and geographic distribution of patients with maxillofacial prosthetics in the capital region of Korea. MATERIALS AND METHODS This retrospective analytical multicenter study was performed by chart reviews. This study included patients who visited the department of prosthodontics at four university dental hospitals for maxillofacial prosthetic rehabilitation. Patients with facial and congenital defects or with insufficient medical data were excluded. The patients were classified into three categories based on the location of the defect. Patients' sex, age, and residential area were analyzed. Pearson's chi-square test with a significance level of 0.05 was used to analyze the variables. RESULTS Among 540 patients with maxillofacial prosthetics, there were 284 (52.59%) male patients and 256 (47.41%) female patients. The number of the patients varied greatly by hospital. Most patients were older than 70, and the most common defect was a hard palate defect. Chi-square analysis did not identify any significant differences in sex, age, and distance to hospital for any defect group (P>.05). CONCLUSION The results of this study indicated that there was imbalance in the distribution of patients with maxillofacial prosthetic among the hospitals in the capital region of Korea. Considerations on specialists and insurance policies for the improvement of maxillofacial prosthetics in Korea are required. PMID:27350859

Cognitive Neural Prosthetics

PubMed Central

Andersen, Richard A.; Hwang, Eun Jung; Mulliken, Grant H.

2010-01-01

The cognitive neural prosthetic (CNP) is a very versatile method for assisting paralyzed patients and patients with amputations. The CNP records the cognitive state of the subject, rather than signals strictly related to motor execution or sensation. We review a number of high-level cortical signals and their application for CNPs, including intention, motor imagery, decision making, forward estimation, executive function, attention, learning, and multi-effector movement planning. CNPs are defined by the cognitive function they extract, not the cortical region from which the signals are recorded. However, some cortical areas may be better than others for particular applications. Signals can also be extracted in parallel from multiple cortical areas using multiple implants, which in many circumstances can increase the range of applications of CNPs. The CNP approach relies on scientific understanding of the neural processes involved in cognition, and many of the decoding algorithms it uses also have parallels to underlying neural circuit functions. PMID:19575625

Reflections on the present and future of upper limb prostheses.

PubMed

Farina, Dario; Amsüss, Sebastian

2016-01-01

Despite progress in research and media attention on active upper limb prostheses, presently the most common commercial upper limb prosthetic devices are not fundamentally different from solutions offered almost one century ago. Limited information transfer for both control and sensory-motor integration and challenges in socket technology have been major obstacles. By analysing the present state-of-the-art and academic achievements, we provide our opinion on the future of upper limb prostheses. We believe that surgical procedures for muscle reinnervation and osseointegration will become increasingly clinically relevant; muscle electrical signals will remain the main clinical means for prosthetic control; and chronic electrode implants, first in muscles (control), then in nerves (sensory feedback), will become viable clinical solutions. After decades of suspended clinically relevant progress, it is foreseeable that a new generation of upper limb prostheses will enter the market in the near future based on such advances, thereby offering substantial clinical benefit for patients.

The FDA's role in medical device clinical studies of human subjects

NASA Astrophysics Data System (ADS)

Saviola, James

2005-03-01

This paper provides an overview of the United States Food and Drug Administration's (FDA) role as a regulatory agency in medical device clinical studies involving human subjects. The FDA's regulations and responsibilities are explained and the device application process discussed. The specific medical device regulatory authorities are described as they apply to the development and clinical study of retinal visual prosthetic devices. The FDA medical device regulations regarding clinical studies of human subjects are intended to safeguard the rights and safety of subjects. The data gathered in pre-approval clinical studies provide a basis of valid scientific evidence in order to demonstrate the safety and effectiveness of a medical device. The importance of a working understanding of applicable medical device regulations from the beginning of the device development project is emphasized particularly for novel, complex products such as implantable visual prosthetic devices.

Outdoor dynamic subject-specific evaluation of internal stresses in the residual limb: hydraulic energy-stored prosthetic foot compared to conventional energy-stored prosthetic feet.

PubMed

Portnoy, Sigal; Kristal, Anat; Gefen, Amit; Siev-Ner, Itzhak

2012-01-01

The prosthetic foot plays an important role in propelling, breaking, balancing and supporting body loads while the amputee ambulates on different grounds. It is therefore important to quantify the effect of the prosthetic foot mechanism on biomechanical parameters, in order to prevent pressure ulcers and deep tissue injury. Our aim was to monitor the internal stresses in the residuum of transtibial amputation (TTA) prosthetic-users ambulating on different terrains, which the amputees encounter during their daily activities, i.e. paved floor, grass, ascending and descending stairs and slope. We specifically aimed to compare between the internal stresses in the TTA residuum of amputees ambulating with a novel hydraulic prosthetic foot compared to conventional energy storage and return (ESR) prosthetic feet. Monitoring of internal stresses was accomplished using a portable subject-specific real-time internal stress monitor. We found significant decrease (p<0.01) in peak internal stresses and in the loading rate of the amputated limb, while walking with the hydraulic foot, compared to walking with ESR feet. The loading rate calculated while ambulating with the hydraulic foot was at least three times lower than the loading rate calculated while ambulating with the ESR foot. Although the average decrease in internal stresses was ≈ 2-fold larger when replacing single-toe ESR feet with the hydraulic foot than when replacing split-toed ESR feet with the hydraulic foot, the differences were statistically insignificant. Our findings suggest that using a hydraulic prosthetic foot may protect the distal tibial end of the TTA residuum from high stresses, therefore preventing pressure-related injury and pain. Copyright © 2011 Elsevier B.V. All rights reserved.

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

PubMed Central

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.

2015-01-01

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. PMID:22100728

Energy flow analysis of amputee walking shows a proximally-directed transfer of energy in intact limbs, compared to a distally-directed transfer in prosthetic limbs at push-off.

PubMed

Weinert-Aplin, R A; Howard, D; Twiste, M; Jarvis, H L; Bennett, A N; Baker, R J

2017-01-01

Reduced capacity and increased metabolic cost of walking occurs in amputees, despite advances in prosthetic componentry. Joint powers can quantify deficiencies in prosthetic gait, but do not reveal how energy is exchanged between limb segments. This study aimed to quantify these energy exchanges during amputee walking. Optical motion and forceplate data collected during walking at a self-selected speed for cohorts of 10 controls, 10 unilateral trans-tibial, 10 unilateral trans-femoral and 10 bilateral trans-femoral amputees were used to determine the energy exchanges between lower limb segments. At push-off, consistent thigh and shank segment powers were observed between amputee groups (1.12W/kg vs. 1.05W/kg for intact limbs and 0.97W/kg vs. 0.99W/kg for prosthetic limbs), and reduced prosthetic ankle power, particularly in trans-femoral amputees (3.12W/kg vs. 0.87W/kg). Proximally-directed energy exchange was observed in the intact limbs of amputees and controls, while prosthetic limbs displayed distally-directed energy exchanges at the knee and hip. This study used energy flow analysis to show a reversal in the direction in which energy is exchanged between prosthetic limb segments at push-off. This reversal was required to provide sufficient energy to propel the limb segments and is likely a direct result of the lack of push-off power at the prosthetic ankle, particularly in trans-femoral amputees, and leads to their increased metabolic cost of walking. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

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

PubMed

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.

Marker-based method to measure movement between the residual limb and a transtibial prosthetic socket.

PubMed

Childers, Walter Lee; Siebert, Steven

2016-12-01

Limb movement between the residuum and socket continues to be an underlying factor in limb health, prosthetic comfort, and gait performance yet techniques to measure this have been underdeveloped. Develop a method to measure motion between the residual limb and a transtibial prosthetic socket. Single subject, repeated measures with mathematical modeling. The gait of a participant with transtibial amputation was recorded using a motion capture system using a marker set that included arrays on the anterior distal tibia and the lateral epicondyle of the femur. The proximal or distal translation, anterior or posterior translation, and angular movements were quantified. A random Monte Carlo simulation based on the precision of the motion capture system and a model of the bone moving under the skin explored the technique's accuracy. Residual limb tissue stiffness was modeled as a linear spring based on data from Papaioannou et al. Residuum movement relative to the socket went through ~30 mm, 18 mm, and 15° range of motion. Root mean squared errors were 5.47 mm, 1.86 mm, and 0.75° when considering the modeled bone-skin movement in the proximal or distal, anterior or posterior, and angular directions, respectively. The measured movement was greater than the root mean squared error, indicating that this method can measure motion between the residuum and socket. The ability to quantify movement between the residual limb and the prosthetic socket will improve prosthetic treatment through the evaluation of different prosthetic suspensions, socket designs, and motor control of the prosthetic interface. © The International Society for Prosthetics and Orthotics 2015.

100 top-cited scientific papers in limb prosthetics.

PubMed

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.

The comparison of transfemoral amputees using mechanical and microprocessor- controlled prosthetic knee under different walking speeds: A randomized cross-over trial.

PubMed

Cao, Wujing; Yu, Hongliu; Zhao, Weiliang; Meng, Qiaoling; Chen, Wenming

2018-04-20

The microprocessor-controlled prosthetic knees have been introduced to transfemoral amputees due to advances in biomedical engineering. A body of scientific literature has shown that the microprocessor-controlled prosthetic knees improve the gait and functional abilities of persons with transfemoral amputation. The aim of this study was to propose a new microprocessor-controlled prosthetic knee (MPK) and compare it with non-microprocessor-controlled prosthetic knees (NMPKs) under different walking speeds. The microprocessor-controlled prosthetic knee (i-KNEE) with hydraulic damper was developed. The comfortable self-selected walking speeds of 12 subjects with i-KNEE and NMPK were obtained. The maximum swing flexion knee angle and gait symmetry were compared in i-KNEE and NMPK condition. The comfortable self-selected walking speeds of some subjects were higher with i-KNEE while some were not. There was no significant difference in comfortable self-selected walking speed between the i-KNEE and the NMPK condition (P= 0.138). The peak prosthetic knee flexion during swing in the i-KNEE condition was between sixty and seventy degree under any walking speed. In the NMPK condition, the maximum swing flexion knee angle changed significantly. And it increased with walking speed. There is no significant difference in knee kinematic symmetry when the subjects wear the i-KNEE or NMPK. The results of this study indicated that the new microprocessor-controlled prosthetic knee was suitable for transfemoral amputees. The maximum swing flexion knee angle under different walking speeds showed different properties in the NMPK and i-KNEE condition. The i-KNEE was more adaptive to speed changes. There was little difference of comfortable self-selected walking speed between i-KNEE and NMPK condition.

INTERVENTIONS TO MANAGE RESIDUAL LIMB ULCERATION DUE TO PROSTHETIC USE IN INDIVIDUALS WITH LOWER EXTREMITY AMPUTATION: A SYSTEMATIC REVIEW OF THE LITERATURE.

PubMed

Highsmith, M Jason; Kahle, Jason T; Klenow, Tyler D; Andrews, Casey R; Lewis, Katherine L; Bradley, Rachel C; Ward, Jessica M; Orriola, John J; Highsmith, James T

2016-09-01

Patients with lower extremity amputation (LEA) experience 65% more dermatologic issues than non-amputees, and skin problems are experienced by ≈75% of LEA patients who use prostheses. Continuously referring LEA patients to a dermatologist for every stump related skin condition may be impractical. Thus, physical rehabilitation professionals should be prepared to recognize and manage common non-emergent skin conditions in this population. The purpose of this study was to determine the quantity, quality, and strength of available evidence supporting treatment methods for prosthesis-related residual limb (RL) ulcers. Systematic literature review with evidence grading and synthesis of empirical evidence statements (EES) was employed. Three EESs were formulated describing ulcer etiology, conditions in which prosthetic continuance is practical, circumstances likely requiring prosthetic discontinuance, and the consideration of additional medical or surgical interventions. Continued prosthetic use is a viable option to manage minor or early-stage ulcerated residual limbs in compliant patients lacking multiple comorbidities. Prosthetic discontinuance is also a viable method of residual limb ulcer healing and may be favored in the presence of severe acute ulcerations, chronic heavy smoking, intractable pain, rapid volume and weight change, history of chronic ulceration, systemic infections, or advanced dysvascular etiology. Surgery or other interventions may also be necessary in such cases to achieve restored prosthetic ambulation. A short bout of prosthetic discontinuance with a staged re-introduction plan is another viable option that may be warranted in patients with ulceration due to poor RL volume management. High-quality prospective research with larger samples is needed to determine the most appropriate course of treatment when a person with LEA develops an RL ulcer that is associated with prosthetic use.

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

PubMed

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.

Corynebacterium minutissimum vascular graft infection: case report and review of 281 cases of prosthetic device-related Corynebacterium infection.

PubMed

Reece, Rebecca M; Cunha, Cheston B; Rich, Josiah D

2014-09-01

Corynebacterium spp. have proven their pathogenic potential in causing infections, particularly in the setting of immunosuppression and prosthetic devices. We conducted a PubMed literature review of all cases of Corynebacterium prosthetic device infections published in the English language through December 2013. The majority of cases involved peritoneal dialysis and central venous catheters, but prosthetic joints and central nervous system shunts/drains were also involved. The management of these cases in terms of retention or removal of the device was not uniform; however, the overall mortality remained the same among both groups. All of these prosthetic device infections pose potential problems in management when the device cannot be removed safely for the patient, especially with the lack of data on the pathogenicity of Corynebacterium species. However with better identification of species and sensitivities, successful treatment is possible even with retention of the device.

The economic impact of surgically treated peri-prosthetic hip fractures on a university teaching hospital in Wales 7.5-year study.

PubMed

Jones, Andrew R; Williams, Tim; Paringe, Vishal; White, Simon P

2016-02-01

The number of total hip replacements taking place across the UK continues to grow. In an ageing population, with people placing greater demands on their prostheses, the number of peri-prosthetic fractures is increasing. We studied the economic impact this has on a large teaching hospital. All patients with peri-prosthetic femoral fracture in a 7.5 year period were identified. Radiographic and case note analysis was performed. Costings from the finance departments were obtained. 90 cases were identified, 58 female and 32 male, with a mean age of 76 (range: 38-91). 89 of the cases were managed surgically, 66% undergoing revision and 33% receiving open reduction and internal fixation. According to the Vancouver Classification, 3% were Type A, 79% Type B and 18% Type C. The mean length of stay was 43 days. The mean cost of management was £31,370 (range: £6885-£112,327). Patients with type C fractures had the highest mean length of stay at 53 days and mean cost of £33,417. Including rehabilitation costs, our study illustrated a mean cost of £31,370, roughly four times the current basic NHS tariff of £8552. Although implant costs are greater, treatment with revision where appropriate allows earlier weight bearing, reduced length of stay and lower overall cost. Copyright © 2015 Elsevier Ltd. All rights reserved.

Single element ultrasonic imaging of limb geometry: an in-vivo study with comparison to MRI

NASA Astrophysics Data System (ADS)

Zhang, Xiang; Fincke, Jonathan R.; Anthony, Brian W.

2016-04-01

Despite advancements in medical imaging, current prosthetic fitting methods remain subjective, operator dependent, and non-repeatable. The standard plaster casting method relies on prosthetist experience and tactile feel of the limb to design the prosthetic socket. Often times, many fitting iterations are required to achieve an acceptable fit. Use of improper socket fittings can lead to painful pathologies including neuromas, inflammation, soft tissue calcification, and pressure sores, often forcing the wearer to into a wheelchair and reducing mobility and quality of life. Computer software along with MRI/CT imaging has already been explored to aid the socket design process. In this paper, we explore the use of ultrasound instead of MRI/CT to accurately obtain the underlying limb geometry to assist the prosthetic socket design process. Using a single element ultrasound system, multiple subjects' proximal limbs were imaged using 1, 2.25, and 5 MHz single element transducers. Each ultrasound transducer was calibrated to ensure acoustic exposure within the limits defined by the FDA. To validate image quality, each patient was also imaged in an MRI. Fiducial markers visible in both MRI and ultrasound were used to compare the same limb cross-sectional image for each patient. After applying a migration algorithm, B-mode ultrasound cross-sections showed sufficiently high image resolution to characterize the skin and bone boundaries along with the underlying tissue structures.

Systematic review of effects of current transtibial prosthetic socket designs-Part 1: Qualitative outcomes.

PubMed

Safari, Mohammad Reza; Meier, Margrit Regula

2015-01-01

This review is an attempt to untangle the complexity of transtibial prosthetic socket fit, determine the most important characteristic for a successful fitting, and perhaps find some indication of whether a particular prosthetic socket type might be best for a given situation. Further, it is intended to provide directions for future research. We followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and used medical subject headings and standard key words to search for articles in relevant databases. No restrictions were made on study design or type of outcome measure. From the obtained search results (n = 1,863), 35 articles were included. The relevant data were entered into a predefined data form that incorporated the Downs and Black risk of bias assessment checklist. Results for the qualitative outcomes (n = 19 articles) are synthesized. Total surface bearing sockets lead to greater activity levels and satisfaction in active persons with amputation, those with a traumatic cause of amputation, and younger persons with amputation than patellar tendon bearing sockets. Evidence on vacuum-assisted suction and hydrostatic sockets is inadequate, and further studies are much needed. To improve the scientific basis for prescription, comparison of and correlation between mechanical properties of interface material, socket designs, user characteristics, and outcome measures should be conducted and reported in future studies.

Molecular Identification of Human Fungal Pathogens

DTIC Science & Technology

2008-03-01

reported this period: Drees M, Wickes BL, Gupta M, Hadley S. Lecythophora mutabilis prosthetic valve endocarditis in a diabetic patient. Med Mycol. (2007...Wickes BL, Gupta M, Hadley S. 2007. Lecythophora mutabilis prosthetic valve endocarditis in a diabetic patient. Med Mycol. 45:463-467. 9...information: http://www.informaworld.com/smpp/title~content=t713694156 Lecythophora mutabilis prosthetic valve endocarditis in a diabetic patient Marci

Custom-made laser-welded titanium implant prosthetic abutment.

PubMed

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.

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

PubMed

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.

Characterisation of prosthetic feet used in low-income countries.

PubMed

Sam, M; Hansen, A H; Childress, D S

2004-08-01

Eleven kinds of prosthetic feet that were designed for use in low-income countries were mechanically characterised in this study. Masses of the different kinds of prosthetic feet varied substantially. Dynamic properties, including damping ratios and resonant frequencies, were obtained from step unloading tests of the feet while interacting with masses comparable to the human body. Data showed that for walking, the feet can be appropriately modeled using their quasistatic properties since natural frequencies were high compared to walking frequencies and since damping ratios were small. Roll-over shapes, the effective rocker (cam) geometries that the feet deform to under walking loads, were determined using a quasistatic loading technique and a spatial transformation of the ground reaction force's centre of pressure. The roll-over shapes for most of the prosthetic feet studied were similar to the roll-over shape of the SACH (solid-ankle cushioned heel) prosthetic foot. All roll-over shapes showed a lack of forefoot support, which may cause a "drop-off" experience at the end of single limb stance and shorter step lengths of the contralateral limb. The roll-over shapes of prosthetic feet appear useful in characterization of foot function.

Influence of Prosthetic Screw Material on Joint Stability in Passive and Non-Passive Implant-Supported Dentures

PubMed Central

Spazzin, Aloísio Oro; Henriques, Guilherme Elias Pessanha; de Arruda Nóbilo, Mauro Antônio; Consani, Rafael Leonardo Xediek; Correr-Sobrinho, Lourenço; Mesquita, Marcelo Ferraz

2009-01-01

Objectives: This study evaluated the influence of prosthetic screw material on joint stability in implantsupported dentures at two levels of fit. Methods: Ten mandibular implant-supported dentures were fabricated. Twenty cast models were fabricated using these dentures. Four groups (n=10) were tested, according to the vertical fit of the dentures [passive and non-passive] and prosthetic screw materials [titanium (Ti) or gold (Au) alloy]. The one-screw test was performed to quantify the vertical misfits using an optic microscope. The loosening torque for the prosthetic screws was measured 24 hours after the tightening torque (10 Ncm) using a digital torque meter. Data were analyzed by two-way ANOVA and Tukey’s test (α=0.05). Results: Overall, dentures with passive fit and Ti screws resulted in significantly higher loosening torque of the prosthetic screws (p<0.05). No significant interaction was found between fit level and screw material (p=0.199). The prosthetic screw material and fit of implant-supported dentures have an influence on screw joint stability. Ti screws presented higher joint stability than Au screws and minimum of misfit should be found clinically to improve the mechanical behavior of the screw joint. PMID:20148135

How do prosthetic stiffness, height and running speed affect the biomechanics of athletes with bilateral transtibial amputations?

PubMed Central

Taboga, Paolo; Grabowski, Alena M.

2017-01-01

Limited available information describes how running-specific prostheses and running speed affect the biomechanics of athletes with bilateral transtibial amputations. Accordingly, we quantified the effects of prosthetic stiffness, height and speed on the biomechanics of five athletes with bilateral transtibial amputations during treadmill running. Each athlete performed a set of running trials with 15 different prosthetic model, stiffness and height combinations. Each set of trials began with the athlete running on a force-measuring treadmill at 3 m s−1, subsequent trials incremented by 1 m s−1 until they achieved their fastest attainable speed. We collected ground reaction forces (GRFs) during each trial. Prosthetic stiffness, height and running speed each affected biomechanics. Specifically, with stiffer prostheses, athletes exhibited greater peak and stance average vertical GRFs (β = 0.03; p < 0.001), increased overall leg stiffness (β = 0.21; p < 0.001), decreased ground contact time (β = −0.07; p < 0.001) and increased step frequency (β = 0.042; p < 0.001). Prosthetic height inversely associated with step frequency (β = −0.021; p < 0.001). Running speed inversely associated with leg stiffness (β = −0.58; p < 0.001). Moreover, at faster running speeds, the effect of prosthetic stiffness and height on biomechanics was mitigated and unchanged, respectively. Thus, prosthetic stiffness, but not height, likely influences distance running performance more than sprinting performance for athletes with bilateral transtibial amputations. PMID:28659414

Energy expenditure of wheeling and walking during prosthetic rehabilitation in a woman with bilateral transfemoral amputations.

PubMed

Wu, Y J; Chen, S Y; Lin, M C; Lan, C; Lai, J S; Lien, I N

2001-02-01

To compare the energy expenditure of locomotion by wheelchair with that required for prosthetic ambulation in a person with bilateral transfemoral (TF) amputations. Observational, single patient, descriptive. An 80-meter long rectangular hallway in a rehabilitation unit. A 41-year-old woman with bilateral TF amputations that were performed 79 days before her admission to the rehabilitation unit. The oxygen uptake, oxygen cost, heart rate, speed, cadence, and stride length of walking measured during a 4-month course of prosthetic rehabilitation. Five locomotion conditions were evaluated: (1) wheelchair propulsion, (2) walking with short-leg prostheses (stubbies) and a walker, (3) long-leg prostheses and a walker, (4) long-leg prostheses without knee mechanism and axillary crutches, and (5) long-leg prostheses with right polycentric knee and left locked knee and axillary crutches. A portable and telemetric system was used to measure the metabolic parameters. An arm ergometry graded exercise test was performed at the end of rehabilitation. Oxygen cost (range, 466%--707% of that of wheeling) and heart rate (range, 106%--116% of that of wheeling) were higher during walking with various combinations of prostheses and walking aids. The speed of prosthetic walking was only 24% to 33% of that of wheeling. Our patient preferred using a wheelchair to prosthetic walking after discharge. People with bilateral TF amputations require very high cardiorespiratory endurance to fulfill the energy demand during prosthetic rehabilitation. The high energy cost of prosthetic walking will limit its application in daily activities.

How do prosthetic stiffness, height and running speed affect the biomechanics of athletes with bilateral transtibial amputations?

PubMed

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

2017-06-01

Limited available information describes how running-specific prostheses and running speed affect the biomechanics of athletes with bilateral transtibial amputations. Accordingly, we quantified the effects of prosthetic stiffness, height and speed on the biomechanics of five athletes with bilateral transtibial amputations during treadmill running. Each athlete performed a set of running trials with 15 different prosthetic model, stiffness and height combinations. Each set of trials began with the athlete running on a force-measuring treadmill at 3 m s -1 , subsequent trials incremented by 1 m s -1 until they achieved their fastest attainable speed. We collected ground reaction forces (GRFs) during each trial. Prosthetic stiffness, height and running speed each affected biomechanics. Specifically, with stiffer prostheses, athletes exhibited greater peak and stance average vertical GRFs ( β = 0.03; p < 0.001), increased overall leg stiffness ( β = 0.21; p < 0.001), decreased ground contact time ( β = -0.07; p < 0.001) and increased step frequency ( β = 0.042; p < 0.001). Prosthetic height inversely associated with step frequency ( β = -0.021; p < 0.001). Running speed inversely associated with leg stiffness ( β = -0.58; p < 0.001). Moreover, at faster running speeds, the effect of prosthetic stiffness and height on biomechanics was mitigated and unchanged, respectively. Thus, prosthetic stiffness, but not height, likely influences distance running performance more than sprinting performance for athletes with bilateral transtibial amputations. © 2017 The Author(s).

Impact of a stance phase microprocessor-controlled knee prosthesis on level walking in lower functioning individuals with a transfemoral amputation.

PubMed

Eberly, Valerie J; Mulroy, Sara J; Gronley, JoAnne K; Perry, Jacquelin; Yule, William J; Burnfield, Judith M

2014-12-01

For individuals with transfemoral amputation, walking with a prosthesis presents challenges to stability and increases the demand on the hip of the prosthetic limb. Increasing age or comorbidities magnify these challenges. Computerized prosthetic knee joints improve stability and efficiency of gait, but are seldom prescribed for less physically capable walkers who may benefit from them. To compare level walking function while wearing a microprocessor-controlled knee (C-Leg Compact) prosthesis to a traditionally prescribed non-microprocessor-controlled knee prosthesis for Medicare Functional Classification Level K-2 walkers. Crossover. Stride characteristics, kinematics, kinetics, and electromyographic activity were recorded in 10 participants while walking with non-microprocessor-controlled knee and Compact prostheses. Walking with the Compact produced significant increase in velocity, cadence, stride length, single-limb support, and heel-rise timing compared to walking with the non-microprocessor-controlled knee prosthesis. Hip and thigh extension during late stance improved bilaterally. Ankle dorsiflexion, knee extension, and hip flexion moments of the prosthetic limb were significantly improved. Improvements in walking function and stability on the prosthetic limb were demonstrated by the K-2 level walkers when using the C-Leg Compact prosthesis. Understanding the impact of new prosthetic designs on gait mechanics is essential to improve prescription guidelines for deconditioned or older persons with transfemoral amputation. Prosthetic designs that improve stability for safety and walking function have the potential to improve community participation and quality of life. © The International Society for Prosthetics and Orthotics 2013.

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

PubMed

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.

Factors associated with tooth loss and prosthodontic status among Sudanese adults.

PubMed

Khalifa, Nadia; Allen, Patrick F; Abu-bakr, Neamat H; Abdel-Rahman, Manar E

2012-01-01

A study was conducted to determine the degree of tooth loss, factors influencing tooth loss, and the extent of prosthodontic rehabilitation in Sudanese adults (≥ 16 years old) attending outpatient clinics in Khartoum State. Pearson and multivariate analyses were used to examine the relationships between tooth loss and specific characteristics determined through interviews and clinical examinations. The mean number of missing teeth was 3.6 (SD, 4.9) and the prevalence of edentulism was 0.1%. The prevalence of tooth loss (missing at least one tooth) was 78%; 66.9% of tooth loss was due to caries, and 11.2% was attributable to other reasons. Prosthetic replacement of missing teeth was evident in 3%, whereas a need for prosthetic replacement was evident in 57%. Having < 20 teeth was associated with age, gender, and socioeconomic status; tooth loss due to caries was associated with age, tribe, frequency of tooth-brushing, and a low rate of dental consultation. Tooth loss due to other reasons was associated with age, tribe, education, periodontal pocketing, tobacco use, tooth wear, and prosthetic status. The results of the present study indicated that the major cause of tooth loss was dental caries, thus emphasizing the importance of a public prevention-based healthcare program. Replacement of missing teeth was uncommon in the study subjects, which may reflect lack of access to this type of oral healthcare.

Recurrent prosthetic valve endocarditis caused by Aspergillus delacroxii (formerly Aspergillus nidulans var. echinulatus)

PubMed Central

Uhrin, Gábor Balázs; Jensen, Rasmus Hare; Korup, Eva; Grønlund, Jens; Hjort, Ulla; Moser, Claus; Arendrup, Maiken Cavling; Schønheyder, Henrik Carl

2015-01-01

We report Aspergillus delacroxii (formerly Aspergillus nidulans var. echinulatus) causing recurrent prosthetic valve endocarditis. The fungus was the sole agent detected during replacement of a mechanical aortic valve conduit due to abscess formation. Despite extensive surgery and anti-fungal treatment, the patient had a cerebral hemorrhage 4 months post-surgery prompting a diagnosis of recurrent prosthetic valve endocarditis and fungemia. PMID:26909244

Proceedings on Combating the Unrestricted Warfare Threat: Integrating Strategy, Analysis, and Technology, 20-21 March 2007

DTIC Science & Technology

2007-03-01

Prosthetics to enable return to units without loss of capability Quantum...and will give us a big advantage in terms of unrestricted warfare. Figure 17 high-Productivity Computing System PRoSThETICS We have an exciting...program in prosthetics (Figure 18). It started with a monkey at Duke University. We put microelectronic implants into her brain, taught her

Prosthetic Joint Infections

PubMed Central

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

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

PubMed

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 prosthetic hand and the proposed distance-fitting procedures may represent a possible low-cost alternative for children in developing countries and those who have limited access to health care providers. Further studies should examine the functionality, validity, durability, benefits, and rejection rate of this type of low-cost 3D-printed prosthetic device.

Advances in upper extremity prosthetics.

PubMed

Zlotolow, Dan A; Kozin, Scott H

2012-11-01

Until recently, upper extremity prostheses had changed little since World War II. In 2006, the Defense Advanced Research Projects Agency responded to an increasing number of military amputees with the Revolutionizing Prosthetics program. The program has yielded several breakthroughs both in the engineering of new prosthetic arms and in the control of those arms. Direct brain-wave control of a limb with 22° of freedom may be within reach. In the meantime, advances such as individually powered digits have opened the door to multifunctional full and partial hand prostheses. Restoring sensation to the prosthetic limb remains a major challenge to full integration of the limb into a patient's self-image. Copyright © 2012 Elsevier Inc. All rights reserved.

Afebrile Pannus-Induced Blood Culture-Negative Mechanical Valve Endocarditis.

PubMed

Matsukuma, Seiji; Eishi, Kiyoyuki; Tanigawa, Kazuyoshi; Miura, Takashi; Matsumaru, Ichiro; Hisatomi, Kazuki; Tsuneto, Akira

2016-12-01

The diagnosis of prosthetic valve endocarditis may be challenging in patients with an atypical clinical presentation. Virtually all infections associated with mechanical prosthetic valves are localized to the prosthesis-tissue junction at the sewing ring and are accompanied by tissue destruction around the prosthesis. Because the orifice of the mechanical prosthetic valve is made of metal and pyrolytic carbon, which do not enable the adherence of microorganisms, any vegetation originating from the interior of the valve orifice is usually rare. Here we present a rare case of pannus-induced mechanical prosthetic valve endocarditis that was difficult to diagnose. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Three-Dimensional Printing of Prosthetic Hands for Children.

PubMed

Burn, Matthew B; Ta, Anderson; Gogola, Gloria R

2016-05-01

Children with hand reductions, whether congenital or traumatic, have unique prosthetic needs. They present a challenge because of their continually changing size due to physical growth as well as changing needs due to psychosocial development. Conventional prosthetics are becoming more technologically advanced and increasingly complex. Although these are welcome advances for adults, the concomitant increases in weight, moving parts, and cost are not beneficial for children. Pediatric prosthetic needs may be better met with simpler solutions. Three-dimensional printing can be used to fabricate rugged, light-weight, easily replaceable, and very low cost assistive hands for children. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Electrochemical Deposition of Nanostructured Conducting Polymer Coatings on Neural Prosthetic Devices

NASA Astrophysics Data System (ADS)

Yang, Junyan; Martin, David

2003-03-01

Micromachined neural prosthetic devices facilitate the functional stimulation of and recording from the central nervous system (CNS). These devices have been fabricated to consist of silicon shanks that have gold or iridium sites along their surface. Our goal is to improve the biocompatibility and long-term performance of the neural prosthetic probes when they are implanted chronically in the brain. In our most recent efforts we have established that electrochemical polymerization can be used to deposit fuzzy coatings of conducting polymers specifically on the electrode sites. For neural prosthetic devices that are intended for long term implantation, we need to develop surfaces that provide intimate contact and promote efficient signal transport at the interface of the microelectrode array and brain tissue. We have developed methods to rapidly and reliably fabricate nanostructured conducting polymer coatings on the electrode probes using templated and surfactant-mediated techniques. Conducting polymer nanomushrooms and nanohairs of polypyrrole (PPy) were electrochemically polymerized onto the functional sites of neural probes by using either nanoporous block copolymers thin films, "track-etched" polycarbonate films or anodic aluminium oxide membranes as templates. Nanofibers of conducting polymers have also been successfully obtained by polymerizations in the presence of surfactants. The influence of current density, monomer concentration, surfactant concentration, and deposition charge on the thickness and morphology of the nanostructured conducting polymer coatings has been studied by optical, scanned probe, scanning electron and transmission electron microscopy. As compared with the normal nodular morphology of polypyrrole, the nanostructured morphologies grown from the neural electrode result in fuzzy coatings with extremely high surface area. The electrical properties of the polymer coatings were studied by Impedance Spectroscopy (IS) and Cyclic Voltammetry (CV). The significant drop in impedance in magnitude and phase angle is consistent with an increase of the surface area due to the roughened surface morphology.

Use of the DEKA Arm for amputees with brachial plexus injury: A case series

PubMed Central

Fantini, Christopher; Latlief, Gail; Phillips, Samuel; Sasson, Nicole; Sepulveda, Eve

2017-01-01

Objective Patients with upper limb amputation and brachial plexus injuries have high rates of prosthesis rejection. Study purpose is to describe experiences of subjects with transhumeral amputation and brachial plexus injury, who were fit with, and trained to use, a DEKA Arm. Methods This was a mixed-methods study utilizing qualitative (e.g. interview, survey) and quantitative data (e.g. self-report and performance measures). Subject 1, a current prosthesis user, had a shoulder arthrodesis. Subject 2, not a prosthesis user, had a subluxed shoulder. Both were trained in laboratory and participated in a trial of home use. Descriptive analyses of processes and outcomes were conducted. Results Subject 1 was fitted with the transhumeral configuration (HC) DEKA Arm using a compression release stabilized socket. He had 12 hours of prosthetic training and participated in all home study activities. Subject 1 had improved dexterity and prosthetic satisfaction with the DEKA Arm and reported better quality of life (QOL) at the end of participation. Subject 2 was fit with the shoulder configuration (SC) DEKA Arm using a modified X-frame socket. He had 30 hours of training and participated in 3 weeks of home activities. He reported less functional disability at the end of training as compared to baseline, but encountered personal problems and exacerbation of PTSD symptoms and withdrew from home use portion at 3 weeks. Both subjects reported functional benefits from use, and expressed a desire to receive a DEKA Arm in the future. Discussion This paper reported on two different strategies for prosthetic fitting and their outcomes. The advantages and limitations of each approach were discussed. Conclusion Use of both the HC and SC DEKA Arm for patients with TH amputation and brachial plexus injury was reported. Lessons learned may be instructive to clinicians considering prosthetic choices for future cases. PMID:28628623

Echocardiographic Assessment of Heart Valve Prostheses

PubMed Central

Sordelli, Chiara; Severino, Sergio; Ascione, Luigi; Coppolino, Pasquale; Caso, Pio

2014-01-01

Patients submitted to valve replacement with mechanical or biological prosthesis, may present symptoms related either to valvular malfunction or ventricular dysfunction from other causes. Because a clinical examination is not sufficient to evaluate a prosthetic valve, several diagnostic methods have been proposed to assess the functional status of a prosthetic valve. This review provides an overview of echocardiographic and Doppler techniques useful in evaluation of prosthetic heart valves. Compared to native valves, echocardiographic evaluation of prosthetic valves is certainly more complex, both for the examination and the interpretation. Echocardiography also allows discriminating between intra- and/or peri-prosthetic regurgitation, present in the majority of mechanical valves. Transthoracic echocardiography (TTE) requires different angles of the probe with unconventional views. Transesophageal echocardiography (TEE) is the method of choice in presence of technical difficulties. Three-dimensional (3D)-TEE seems to be superior to 2D-TEE, especially in the assessment of paravalvular leak regurgitation (PVL) that it provides improved localization and analysis of the PVL size and shape. PMID:28465917

Structural Integration and Control of Peerless Human-like Prosthetic Hand

NASA Astrophysics Data System (ADS)

Dave, Ankit; Muthu, P.; Karthikraj, V.; Latha, S.

2018-04-01

Limb damage can create severe disturbance in movement and operative abilities wherein the prosthetic rehabilitation has the potential to replace function and enhance the quality of life. This paper presents a humanlike prosthetic hand using such unique design concept of hand model using artificial bones, ligaments, and tendons controlled using Arduino. Amongst various platforms available, Arduino is known for its adaptability, adoration and low cost. The design of prosthetic hand has a unique structure with all carpal, metacarpal, and phalanges which are bones of the hand. These bones are attached to each other following the pattern of human hand using the polymeric rubber as a functioning ligament. Furthermore, this structure of finger is driven by tendons attached to all fingers and passes through the ligaments working as pulley resulting in more degrees of freedom. The motor can twitch the tendons to achieve the action of fingers. Thus the servos, controlled by an Arduino, are used to regulate the movement mechanism of the prosthetic hand.

Control of a powered prosthetic device via a pinch gesture interface

NASA Astrophysics Data System (ADS)

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.

Prosthetic Tool For Holding Small Ferromagnetic Parts

NASA Technical Reports Server (NTRS)

Norton, William E.; Carden, James R.; Belcher, Jewell G., Jr.; Vest, Thomas W.

1995-01-01

Tool attached to prosthetic hand or arm enables user to hold nails, screws, nuts, rivets, and other small ferromagnetic objects on small magnetic tip. Device adjusted to hold nail or screw at proper angle for hammering or for use of screwdriver, respectively. Includes base connector with threaded outer surface and lower male member inserted in standard spring-action, quick-connect/quick-disconnect wrist adapter on prosthetic hand or arm.

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

DTIC Science & Technology

2017-10-01

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...discomfort. 2. KEYWORDS: Provide a brief list of keywords (limit to 20 words). Prosthesis, prosthesis fit, technology , skin problems, amputee

Fatigue testing of energy storing prosthetic feet.

PubMed

Toh, S L; Goh, J C; Tan, P H; Tay, T E

1993-12-01

This paper describes a simple approach to the fatigue testing of prosthetic feet. A fatigue testing machine for prosthetic feet was designed as part of the programme to develop an energy storing prosthetic foot (ESPF). The fatigue tester does not simulate the loading pattern on the foot during normal walking. However, cyclic vertical loads are applied to the heel and forefoot during heel-strike and toe-off respectively, for 500,000 cycles. The maximum load applied was chosen to be 1.5 times that applied by the bodyweight of the amputee and the test frequency was chosen to be 2 Hz to shorten the test duration. Four prosthetic feet were tested: two Lambda feet (a newly developed ESPF), a Kingsley SACH foot and a Proteor SACH foot. It was found that the Lambda feet have very good fatigue properties. The Kingsley SACH foot performed better than the Proteor model, with no signs of wear at the heel. The results obtained using the simple approach was found to be comparable to the results from more complex fatigue machines which simulate the load pattern during normal walking. This suggests that simple load simulating machines, which are less costly and require less maintenance, are useful substitutes in studying the fatigue properties of prosthetic feet.

Prosthetic implant treatment of the edentulous maxilla with overdenture.

PubMed

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.

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

PubMed

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.

A three-dimensional finite element study on the stress distribution pattern of two prosthetic abutments for external hexagon implants.

PubMed

Moreira, Wagner; Hermann, Caio; Pereira, Jucélio Tomás; Balbinoti, Jean Anacleto; Tiossi, Rodrigo

2013-10-01

The purpose of this study was to evaluate the mechanical behavior of two different straight prosthetic abutments (one- and two-piece) for external hex butt-joint connection implants using three-dimensional finite element analysis (3D-FEA). Two 3D-FEA models were designed, one for the two-piece prosthetic abutment (2 mm in height, two-piece mini-conical abutment, Neodent) and another one for the one-piece abutment (2 mm in height, Slim Fit one-piece mini-conical abutment, Neodent), with their corresponding screws and implants (Titamax Ti, 3.75 diameter by 13 mm in length, Neodent). The model simulated the single restoration of a lower premolar using data from a computerized tomography of a mandible. The preload (20 N) after torque application for installation of the abutment and an occlusal loading were simulated. The occlusal load was simulated using average physiological bite force and direction (114.6 N in the axial direction, 17.1 N in the lingual direction and 23.4 N toward the mesial at an angle of 75° to the occlusal plan). The regions with the highest von Mises stress results were at the bottom of the initial two threads of both prosthetic abutments that were tested. The one-piece prosthetic abutment presented a more homogeneous behavior of stress distribution when compared with the two-piece abutment. Under the simulated chewing loads, the von Mises stresses for both tested prosthetic-abutments were within the tensile strength values of the materials analyzed which thus supports the clinical use of both prosthetic abutments.

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

PubMed

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.

Bruxism and prosthetic treatment: a critical review.

PubMed

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.

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

PubMed

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.

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

PubMed Central

2014-01-01

Background 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. Methods 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. Results 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. Conclusion 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. PMID:25085005

The importance of aerodynamics for prosthetic limb design used by competitive cyclists with an amputation: An introduction.

PubMed

Dyer, Bryce

2015-06-01

This study introduces the importance of the aerodynamics to prosthetic limb design for athletes with either a lower-limb or upper-limb amputation. The study comprises two elements: 1) An initial experiment investigating the stability of outdoor velodrome-based field tests, and 2) An experiment evaluating the application of outdoor velodrome aerodynamic field tests to detect small-scale changes in aerodynamic drag respective of prosthetic limb componentry changes. An outdoor field-testing method is used to detect small and repeatable changes in the aerodynamic drag of an able-bodied cyclist. These changes were made at levels typical of alterations in prosthetic componentry. The field-based test method of assessment is used at a smaller level of resolution than previously reported. With a carefully applied protocol, the field test method proved to be statistically stable. The results of the field test experiments demonstrate a noticeable change in overall athlete performance. Aerodynamic refinement of artificial limbs is worthwhile for athletes looking to maximise their competitive performance. A field-testing method illustrates the importance of the aerodynamic optimisation of prosthetic limb components. The field-testing protocol undertaken in this study gives an accessible and affordable means of doing so by prosthetists and sports engineers. Using simple and accessible field-testing methods, this exploratory experiment demonstrates how small changes to riders' equipment, consummate of the scale of a small change in prosthetics componentry, can affect the performance of an athlete. Prosthetists should consider such opportunities for performance enhancement when possible. © The International Society for Prosthetics and Orthotics 2014.

Incidence of Prosthetic Complications associated with Implant-borne Prosthesis in a Sleep Disorder Center.

PubMed

Suneel, Venkatesh B; Kotian, Santhosh; Jujare, Ravikanth H; Shetty, Adarsh K; Nidhi, Sneh; Grover, Shehkar

2017-09-01

Obstructive sleep apnea (OSA) is one of the common prevalent conditions present worldwide. The process of abnormal habits related to clenching and grinding of teeth is referred to as bruxism and is characterized under the heading of parafunctional activity of the masticatory system. Osseointegrated dental implants represent advancements in the field of odontology. Despite its high success rate, failure and complications are often associated with dental implant treatment due to a number of factors. Hence, we aimed for the present study to assess the incidence of prosthetic complications in patients rehabilitated with implant-borne prosthesis in a sleep disorder unit. The present study included the assessment of all the patients who underwent prosthetic rehabilitation by dental implants. An experienced registered prosthodontist was given duty for examination of all the cases from the record file data. Prosthetic complications in the patients were identified using photographs, radiographs, and all other relevant data of the patients obtained from the record files. All types of complications and other factors were recorded separately and analyzed. While correlating the prosthetic complications in OSA patients grouped based on number of dental implants, nonsignificant results were obtained. Significant correlation was observed while comparing the prosthetic complications divided based on type of prosthesis. Fracture of the porcelain was observed in four and eight cases respectively, of screwed and cemented dental implant cases. Some amount of significant correlation existed between the incidences of prosthetic complications and OSA. Proper history of the patients undergoing dental implant procedures should be taken to avoid failure.

[Incidence of hip and knee prosthetic infections in a specialized center of Mexico City].

PubMed

Franco-Cendejas, Rafael; Contreras-Córdova, Erika Lizbeth; Mondragón-Eguiluz, Jaime Arturo; Vanegas-Rodríguez, Edgar Samuel; Ilizaliturri-Sánchez, Víctor Manuel; Galindo-Fraga, Arturo

Hip and knee prosthetic replacements have proven to be the most appropriate treatment in the joints that do not benefit from medical or arthroscopic interventions; however, infections are the most feared complication. It is recommended that the incidence of infection should not exceed 2%. This was an observational, prospective, longitudinal and observational study conducted in patients fitted with a prosthetic joint from August 2011 to July 2012. Patients were followed up pre and post-surgery for one year to identify a prosthetic infection, diagnosed using international parameters. We calculated the incidence of prosthetic infection, as well as the incidence density. A total of 339 patients (179 hip and 160 knee) were included. Variations in the time of pre-operative antibiotics' administration were observed. Six prosthetic infections were identified with an incidence rate of 1.79/339 arthroplasties, 2.2/179 hip procedures, and 1.25/160 knee arthroplasties. An incidence density of 0.02/year for hip arthroplasties and 0.11/year for knee procedures was identified. There were 4 infections of hip and 2 of knee. Five infections were acute and one chronic. The isolated microorganisms were E. faecalis, S. epidermidis (2), S. mitis, S. aureus and P. stomatis. The incidence of prosthetic joint infection in the first year of follow-up at our centre is within the recommended parameters. Surgical techniques and organizational practices influence the results. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

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

PubMed

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.

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

PubMed Central

Merad, Manelle; de Montalivet, Étienne; Touillet, Amélie; Martinet, Noël; Roby-Brami, Agnès; Jarrassé, Nathanaël

2018-01-01

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' coordination models can lead to an intuitive and natural prosthetic control. PMID:29456499

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

PubMed

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 surgery during maxillectomy and prosthodontic technique.

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

PubMed

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 stairs. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

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

PubMed

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.

Development of an above-knee prosthesis equipped with a microcomputer-controlled knee joint: first test results.

PubMed

Aeyels, B; Peeraer, L; Vander Sloten, J; Van der Perre, G

1992-05-01

The shortcomings of conventional above-knee prostheses are due to their lack of adaptive control. Implementation of a microcomputer controlling the knee joint in a passive way has been suggested to enhance the patient's gait comfort, safety and cosmesis. This approach was used in the design of a new prosthetic system for the above-knee amputee, and tested on one patient. The knee joint of a conventional, modular prosthesis was replaced by a knee joint mechanism, equipped with a controllable brake on the knee joint axis. Sensors and a microcomputer were added, keeping the system self-contained. The modularity of the design permits the use of an alternative, external, PC-based control unit, emulating the self-contained one, and offering extended data monitoring and storage facilities. For both units an operating environment was written, including sensor/actuator interfacing and the implementation of a real-time interrupt, executing the control algorithm. A double finite state approach was used in the design of the control algorithm. On a higher level, the mode identification algorithm reveals the patient's intent. Within a specific mode (lower level), the relevant mode control algorithm looks for the current phase within the gait cycle. Within a particular phase, a specific simple control action with the brake replaces normal knee muscle activity. Tests were carried out with one prosthetic patient using a basic control algorithm for level walking, allowing controlled knee flexion during stance phase. The technical feasibility of such a concept is illustrated by the test results, even though only flexion during early stance phase was controlled during the trials.(ABSTRACT TRUNCATED AT 250 WORDS)

Program Evaluation of Outcomes Based Orthotic and Prosthetic Education

DTIC Science & Technology

2008-12-01

the Student Learning Outcomes Assessment group (SLOAC) at California State University Dominguez Hills. She is an assessment expert and consultant...identified in the program-level outcomes (Essential Elements of Learning Outcomes Assessment, Indicators 4 & 5, University Student Learning Outcomes...A short 70-mile trip is changing the lives of O&P students and impacting future care of returning military service members. By Jennifer Hoydicz

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

PubMed Central

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 highest coherence with hand movements. Our results represent a first step toward a more effective and intuitive control of myoelectric hand prostheses. PMID:27799908

Immediate loading with fixed full-arch prostheses in the maxilla: Review of the literature

PubMed Central

Peñarrocha-Oltra, David; Covani, Ugo; Peñarrocha-Diago, Miguel

2014-01-01

Objectives: To critically review the evidence-based literature on immediate loading of implants with fixed full-arch prostheses in the maxilla to determine 1) currently recommended performance criteria and 2) the outcomes that can be expected with this procedure. Study Desing: Studies from 2001 to 2011 on immediate loading with fixed full-arch maxillary prostheses were reviewed. Clinical series with at least 5 patients and 12 months of follow-up were included. Case reports, studies with missing data and repeatedly published studies were excluded. In each study the following was assessed: type of study, implant type, number of patients, number of implants, number of implants per patient, use of post-extraction implants, minimum implant length and diameter, type of prosthesis, time until loading, implant survival rate, prosthesis survival rate, marginal bone loss, complications andmean follow-up time. Criteria for patient selection, implant primary stability and bone regeneration were also studied. Results: Thirteen studies were included, reporting a total of 2484 immediately loaded implants in 365 patients. Currently accepted performance criteria regarding patient and implant selection, and surgical and prosthetic procedures were deduced from the reviewed articles. Implant survival rates went from 87.5% to 100%, prosthesis survival rates from 93.8% to 100% and radiographic marginal bone loss from 0.8 mm to 1.6 mm.No intraoperative complications and only minor prosthetic complications were reported. Conclusions: The literature on immediate loading with fixed full-arch prostheses in the maxilla shows that a successful outcome can be expected if adequate criteria are used to evaluate the patient, choose the implant and perform the surgical and prosthetic treatment. Lack of homogeneity within studies limits the relevance of the conclusions that can be drawn, and more controlled randomized studies are necessary to enable comparison between the immediate and the conventional loading procedures. Key words:Immediate loading, full-arch, dental implants, loading protocols. PMID:24880445

Silicone Molding and Lifetime Testing of Peripheral Nerve Interfaces for Neuroprostheses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gupte, Kimaya; Tolosa, Vanessa

Implantable peripheral nerve cuffs have a large application in neuroprostheses as they can be used to restore sensation to those with upper limb amputations. Modern day prosthetics, while lessening the pain associated with phantom limb syndrome, have limited fine motor control and do not provide sensory feedback to patients. Sensory feedback with prosthetics requires communication between the nervous system and limbs, and is still a challenge to accomplish with amputees. Establishing this communication between the peripheral nerves in the arm and artificial limbs is vital as prosthetics research aims to provide sensory feedback to amputees. Peripheral nerve cuffs restore sensationmore » by electrically stimulating certain parts of the nerve in order to create feeling in the hand. Cuff electrodes have an advantage over standard electrodes as they have high selective stimulation by bringing the electrical interface close to the neural tissue in order to selectively activate targeted regions of a peripheral nerve. In order to further improve the selective stimulation of these nerve cuffs, there is need for finer spatial resolution among electrodes. One method to achieve a higher spatial resolution is to increase the electrode density on the cuff itself. Microfabrication techniques can be used to achieve this higher electrode density. Using L-Edit, a layout editor, microfabricated peripheral nerve cuffs were designed with a higher electrode density than the current model. This increase in electrode density translates to an increase in spatial resolution by at least one order of magnitude. Microfabricated devices also have two separate components that are necessary to understand before implantation: lifetime of the device and assembly to prevent nerve damage. Silicone molding procedures were optimized so that devices do not damage nerves in vivo, and lifetime testing was performed on test microfabricated devices to determine their lifetime in vivo. Future work of this project would include fabricating some of the designed devices and seeing how they compare to the current cuffs in terms of their electrical performance, lifetime, shape, and mechanical properties.« less

Detection of Prosthetic Hip Infection at Revision Arthroplasty by Immunofluorescence Microscopy and PCR Amplification of the Bacterial 16S rRNA Gene

PubMed Central

Tunney, Michael M.; Patrick, Sheila; Curran, Martin D.; Ramage, Gordon; Hanna, Donna; Nixon, James R.; Gorman, Sean P.; Davis, Richard I.; Anderson, Neil

1999-01-01

In this study the detection rates of bacterial infection of hip prostheses by culture and nonculture methods were compared for 120 patients with total hip revision surgery. By use of strict anaerobic bacteriological practice during the processing of samples and without enrichment, the incidence of infection by culture of material dislodged from retrieved prostheses after ultrasonication (sonicate) was 22%. Bacteria were observed by immunofluorescence microscopy in 63% of sonicate samples with a monoclonal antibody specific for Propionibacterium acnes and polyclonal antiserum specific for Staphylococcus spp. The bacteria were present either as single cells or in aggregates of up to 300 bacterial cells. These aggregates were not observed without sonication to dislodge the biofilm. Bacteria were observed in all of the culture-positive samples, and in some cases in which only one type of bacterium was identified by culture, both coccoid and coryneform bacteria were observed by immunofluorescence microscopy. Bacteria from skin-flake contamination were readily distinguishable from infecting bacteria by immunofluorescence microscopy. Examination of skin scrapings did not reveal large aggregates of bacteria but did reveal skin cells. These were not observed in the sonicates. Bacterial DNA was detected in 72% of sonicate samples by PCR amplification of a region of the bacterial 16S rRNA gene with universal primers. All of the culture-positive samples were also positive for bacterial DNA. Evidence of high-level infiltration either of neutrophils or of lymphocytes or macrophages into associated tissue was observed in 73% of patients. Our results indicate that the incidence of prosthetic joint infection is grossly underestimated by current culture detection methods. It is therefore imperative that current clinical practice with regard to the detection and subsequent treatment of prosthetic joint infection be reassessed in the light of these results. PMID:10488193

Incremental benefit of 3D transesophageal echocardiography: a case of a mass overlying a prosthetic mitral valve.

PubMed

Tauras, James M; Zhang, Zhihang; Taub, Cynthia C

2011-05-01

A young woman with a mechanical mitral valve and prosthetic mitral stenosis underwent multiple imaging modalities (including transthoracic ECHO, fluoroscopy, and two-dimensional transesophageal ECHO) to determine the cause of her stenosis. Only three-dimensional transesophageal echocardiography demonstrated the full size and extent of an obstructing mass on the strut and sewing ring of the prosthetic mitral valve. © 2011, Wiley Periodicals, Inc.

The Effect of a Microprocessor Prosthetic Foot on Function and Quality of Life in Transtibial Amputees Who Are Limited Community Ambulators

DTIC Science & Technology

2017-09-01

parallel, randomized, controlled clinical trial designed to determine if a microprocessor controlled prosthetic foot (MPF), with greater range of...clinical trial designed to determine if a microprocessor controlled prosthetic foot (MPF), with greater range of motion and active power, will...Department of the Army position, policy or decision unless so designated by other documentation. CONTRACTING ORGANIZATION: University of Tennessee

24 DOF EMG controlled hybrid actuated prosthetic hand.

PubMed

Atasoy, A; Kaya, E; Toptas, E; Kuchimov, S; Kaplanoglu, E; Ozkan, M

2016-08-01

A complete mechanical design concept of an electromyogram (EMG) controlled hybrid prosthetic hand, with 24 degree of freedom (DOF) anthropomorphic structure is presented. Brushless DC motors along with Shape Memory Alloy (SMA) actuators are used to achieve dexterous functionality. An 8 channel EMG is used for detecting 7 basic hand gestures for control purposes. The prosthetic hand will be integrated with the Neural Network (NNE) based controller in the next phase of the study.

Management of Prosthetic Joint Infection.

PubMed

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.

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

PubMed

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.

Optical 3D methods for measurement of prosthetic wear of total hip arthroplasty: principles, verification and results.

PubMed

Rossler, Tomas; Mandat, Dusan; Gallo, Jiri; Hrabovsky, Miroslav; Pochmon, Michal; Havranek, Vitezslav

2009-07-20

Total hip arthroplasty (THA) significantly improves the quality of life in majority of patients with severe osteoarthritis. However, long-term outcomes of THAs are compromised by aseptic loosening and periprosthetic osteolysis which needs revision surgery. Both of these are causally linked to a prosthetic wear deliberated from the prosthetic articulating surfaces. As a result, there is a need to measure the mode and magnitude of wear. The paper evaluates three optical methods proposed for construction of a device for the non-contact prosthetic wear measurement. Of them, the scanning profilometry achieved promising combination of accuracy and repeatability. Simultaneously, it is time efficient to enable the development of a sensor for wear measurement.

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

PubMed

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.

[Overlay prosthetic solution in subtotal edentation treatment].

PubMed

Tatarciuc, M; Ursache, M; Grădinaru, I

2001-01-01

The preservation of the natural dental roots represents a big advantage for the overdenture prosthetic appliances. The realization of an overdenture needs a perfect correlation of all the clinical and technological factors, in all the prosthetics steps. Another important aspect is represented by the possibility of a correct treatment of the remaining roots. The remaining roots will be correctly endodontically treated. The root section will be prepared with two inclines bucally and orally located. A metallic cup will cover the root section. On the inner surface of the overdenture the dental technician will realize specific preparations corresponding to this cups. This kind of prosthetic treatment is indicated only for patients with a very good oral hygiene and a good general health.

Prosthetic aortic valve endocarditis complicated with annular abscess, sub-aortic obstruction and valve dehiscence.

PubMed

Hassoulas, Joannis; Patrianakos, Alexandros P; Parthenakis, Fragiskos I; Vardas, Panos E

2009-01-01

We present a 76-year-old woman with infective endocarditis of a prosthetic aortic valve. The course of her illness started with an ischaemic stroke and she was admitted with prolonged fever and an episode of loss of consciousness. Echocardiography revealed acute aortic regurgitation and dehiscence of the prosthetic valve with excessive "rocking motion", aortic abscesses and left ventricular outflow obstruction caused by a semilunar shelf of tissue probably due to endocarditis vegetations. She underwent an urgent surgical procedure that confirmed the echocardiographic findings. Our case report reinforces the value of early diagnosis in the presence of a high clinical suspicion of prosthetic valve endocarditis. An extended workup, including transoesophageal echocardiography, in such a patient with a mechanical valve is mandatory.

Late leaflet fracture and embolization of a Duromedics mitral prosthesis.

PubMed

Sudo, K; Sasagawa, N; Ide, H; Nunokawa, M; Fujiki, T; Tonari, K

2000-08-01

A case of leaflet fracture and embolization of a mitral prosthetic valve is described. A 54-year-old man had received mitral valve replacement with an Edwards-Duromedics 29M prosthetic valve, at 10 years ago. Emergency mitral valve replacement was performed because the patient had severe congestive left heart failure with severe acute mitral regurgitation caused by a fracture in one of the mitral valve leaflets. The leaflet, which was fractured into 2 pieces, was removed from the right common iliac artery at 3 months after valve replacement. Visual inspection revealed that the leaflet contained a midline fracture. The fracture originated within a cavitary erosion pit near the major radius of the leaflet. The patient recovered from acute renal failure, requiring hemodialysis for 80 days, and is currently without complaints. We have used a Duromedics mitral valve in 11 patients, from April 1987 to April 1988. No subsequent valve failure has occurred. The diagnosis, treatment and cause of a mechanical valve fracture are discussed.

[The bionic hand].

PubMed

Surke, Carsten; Ducommun Dit Boudry, Pascal; Vögelin, Esther

2015-08-01

The loss of the upper extremity implicates a grave insult in the life of the involved person. To compensate for the loss of function different powered prosthetic devices are available. Ever since their first development 70 years ago numerous improvements in terms of size, weight and wearing comfort have been developed, but issues regarding the control of upper extremity prostheses remain. Slow grasping speed, limited grip positions and especially failure to provide a sensory feedback limit the acceptance in patients. Recent developments are aimed to allow a more intuitive control of the prosthetic device and to provide a sensory feedback to the amputee. Targeted reinnervation reassignes existing muscles to different peripheral nerves thereby enabling them to fulfill alternate functions. Implanting electrodes into muscle bellies of the forearm allows a more accurate control of the prosthesis. Promising results are being achieved by implanting nerve electrodes by establishing bilateral communication between patient and prosthesis. The following review summarizes the current developments of bionic prostheses in the upper extremity.

Beyond war and military medicine: social factors in the development of prosthetics.

PubMed

Reznick, Jeffrey S

2008-01-01

Polytrauma is an immediate outcome of current warfare, and the need to investigate this condition is equally immediate. The value of historical analysis in this endeavor should not be underestimated. It is among the best tools we have to help ensure that current research and practice involve engagement with the social contexts of polytrauma as well as with the medical science of its treatment. This special communication provides historical perspective on certain aspects of the polytraumatic condition--namely, limb loss, prosthetic rehabilitation, and community reintegration after receiving a prosthesis. It discusses the influential role of societal factors in these areas to encourage greater understanding that the care of persons with polytrauma must involve critical thinking about their relationships to and participation in society as well as their treatment by medical science. This special communication also provides historical perspective to enrich appreciation of the value of history for the field of physical medicine and rehabilitation (PM&R), the PM&R clinician, and the PM&R clinical researcher. Readers will learn that historical knowledge puts PM&R research and practice into perspective, reminding us that rehabilitation should involve critical thinking not only about medicine, but also about social roles and the participation of people in society despite physical and psychologic challenges.

A regenerative microchannel neural interface for recording from and stimulating peripheral axons in vivo

NASA Astrophysics Data System (ADS)

FitzGerald, James J.; Lago, Natalia; Benmerah, Samia; Serra, Jordi; Watling, Christopher P.; Cameron, Ruth E.; Tarte, Edward; Lacour, Stéphanie P.; McMahon, Stephen B.; Fawcett, James W.

2012-02-01

Neural interfaces are implanted devices that couple the nervous system to electronic circuitry. They are intended for long term use to control assistive technologies such as muscle stimulators or prosthetics that compensate for loss of function due to injury. Here we present a novel design of interface for peripheral nerves. Recording from axons is complicated by the small size of extracellular potentials and the concentration of current flow at nodes of Ranvier. Confining axons to microchannels of ˜100 µm diameter produces amplified potentials that are independent of node position. After implantation of microchannel arrays into rat sciatic nerve, axons regenerated through the channels forming ‘mini-fascicles’, each typically containing ˜100 myelinated fibres and one or more blood vessels. Regenerated motor axons reconnected to distal muscles, as demonstrated by the recovery of an electromyogram and partial prevention of muscle atrophy. Efferent motor potentials and afferent signals evoked by muscle stretch or cutaneous stimulation were easily recorded from the mini-fascicles and were in the range of 35-170 µV. Individual motor units in distal musculature were activated from channels using stimulus currents in the microampere range. Microchannel interfaces are a potential solution for applications such as prosthetic limb control or enhancing recovery after nerve injury.

Facial identification in very low-resolution images simulating prosthetic vision.

PubMed

Chang, M H; Kim, H S; Shin, J H; Park, K S

2012-08-01

Familiar facial identification is important to blind or visually impaired patients and can be achieved using a retinal prosthesis. Nevertheless, there are limitations in delivering the facial images with a resolution sufficient to distinguish facial features, such as eyes and nose, through multichannel electrode arrays used in current visual prostheses. This study verifies the feasibility of familiar facial identification under low-resolution prosthetic vision and proposes an edge-enhancement method to deliver more visual information that is of higher quality. We first generated a contrast-enhanced image and an edge image by applying the Sobel edge detector and blocked each of them by averaging. Then, we subtracted the blocked edge image from the blocked contrast-enhanced image and produced a pixelized image imitating an array of phosphenes. Before subtraction, every gray value of the edge images was weighted as 50% (mode 2), 75% (mode 3) and 100% (mode 4). In mode 1, the facial image was blocked and pixelized with no further processing. The most successful identification was achieved with mode 3 at every resolution in terms of identification index, which covers both accuracy and correct response time. We also found that the subjects recognized a distinctive face especially more accurately and faster than the other given facial images even under low-resolution prosthetic vision. Every subject could identify familiar faces even in very low-resolution images. And the proposed edge-enhancement method seemed to contribute to intermediate-stage visual prostheses.

Transplants for non-lethal conditions: a case against hand transplantation in minors.

PubMed

Hedges, Charles E; Rosoff, Philip M

2018-06-14

Human allografts for life-threatening organ failure have been demonstrated to be lifesaving and are now considered to be standard of care for many conditions. Transplantation of non-vital anatomic body parts has also been accomplished. Hand transplantation after limb loss in adults has been shown to offer some promising benefits in both functional and psychological measures in preliminary studies. It has been suggested to expand eligibility criteria to include minors, with one such operation having already been performed. With this in mind, we examine the current state of hand transplantation research in the context of available alternatives. We examine the ethics of carrying out these operations in minors, including under the protections of clinical research. We argue that children should not be considered for this surgery due to the substantial risks of immunosuppressive medication, the likelihood that the graft will need to be replaced during the patient's lifetime and the lack of significant compensatory advantages over modern prosthetics. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Rehabilitation and Prosthetic Services

MedlinePlus

... VA Learning University (VALU) SimLearn Libraries (VALNET) VA Software Documentation Library (VDL) About VHA Learn about VHA Forms & ... & Sensory Aids Service (PSAS) Our Mission The mission of the Prosthetic & ...

Design and clinical outcome of a novel 3D-printed prosthetic joint replacement for the human temporomandibular joint.

PubMed

Ackland, David; Robinson, Dale; Lee, Peter Vee Sin; Dimitroulis, George

2018-05-11

Stock prosthetic temporomandibular joint replacements come in limited sizes, and do not always encompass the joint anatomy that presents clinically. The aims of this study were twofold. Firstly, to design a personalized prosthetic total joint replacement for the treatment of a patient's end-stage temporomandibular joint osteoarthritis, to implant the prosthesis into the patient, and assess clinical outcome 12-months post-operatively; and secondly, to evaluate the influence of changes in prosthetic condyle geometry on implant load response during mastication. A 48-year-old female patient with Grade-5 osteoarthritis to the left temporomandibular joint was recruited, and a prosthesis developed to match the native temporomandibular joint anatomy. The prosthesis was 3D printed, sterilized and implanted into the patient, and pain and function measured 12-months post-operatively. The prosthesis load response during a chewing-bite and maximum-force bite was evaluated using a personalized multi-body musculoskeletal model. Simulations were performed after perturbing condyle thickness, neck length and head sphericity. Increases in prosthetic condyle neck length malaligned the mandible and perturbed temporomandibular joint force. Changes in condylar component thickness greatly influenced fixation screw stress response, while a more eccentric condylar head increased prosthetic joint-contact loading. Post-operatively, the prosthetic temporomandibular joint surgery reduced patient pain from 7/10 to 1/10 on a visual analog scale, and increased intercisal opening distance from 22 mm to 38 mm. This study demonstrates effectiveness of a personalized prosthesis that may ultimately be adapted to treat a wide-range of end-stage temporomandibular joint conditions, and highlights sensitivity of prosthesis load response to changes in condylar geometry. Copyright © 2018 Elsevier Ltd. All rights reserved.

The use of a direct manufacturing prosthetic socket system in a rural community in South Africa: A pilot study and lessons for future research.

PubMed

Ennion, Liezel; Johannesson, Anton; Rhoda, Anthea

2017-10-01

Challenges exist with the provision of appropriate mobility assistive devices in rural areas. The use of the direct manufacturing prosthetic socket system is a possible solution to these challenges. The objective of this study was to test and explore the clients' perspectives with the application of this device. Within a mixed-methods approach, a longitudinal sequential explanatory design was applied. The Orthotic and Prosthetic User's Survey was administered to explore the use of the direct manufacturing prosthetic socket system in terms of function, health-related quality of life and client satisfaction. A conveniently selected sample of 21 individuals who suffered a unilateral trans-tibial amputation was included. Data were collected at 1, 3 and 6 months post fitting, and two focus group discussions were also administered. Of the 21 participants recruited, 11 returned for follow up. Although participants reported favourably about the prosthesis, their scores were generally worse than the norms with regard to function and quality of life. Participants highlighted the need for improvement in the cosmetic appearance of the prosthesis. The direct manufacturing prosthetic socket system could be considered as an alternative technique of socket manufacturing for individuals living in rural areas due to the shorter manufacture time and promising initial results, but further research on this topic with a bigger sample is recommended. Clinical relevance The direct manufacturing prosthetic socket system may be considered as an alternative to the traditional prosthetic socket manufacturing technique used in South Africa. As this device requires only one visit and therefore decreased travel by the patients to the hospitals, it could be applicable to more amputees who cannot return to hospital post discharge.

Pilot Study on the Influence of Nutritional Counselling and Implant Therapy on the Nutritional Status in Dentally Compromised Patients

PubMed Central

Wöstmann, Bernd; Simon, Teresa; Neuhäuser-Berthold, Monika; Rehmann, Peter

2016-01-01

Objectives To investigate the impact of implant-prosthetic rehabilitation combined with nutritional counseling on the nutritional status of patients with severely reduced dentitions. Design An explorative intervention study including an intra-individual comparison of 20 patients with severely reduced dentitions in terms of nutrition- and quality of life-related parameters recorded at baseline and at six and twelve months after implant-prosthetic rehabilitation. Participants Twenty patients from the Department of Prosthetic Dentistry of Justus-Liebig University of Giessen, with an mean age of 63 years, who had fewer than ten pairs of antagonists. Measurements The baseline data collection included dental status, a chewing ability test, laboratory parameters, anthropometric data (body mass index), energy supply, a 3-day dietary record, an analysis of the oral health-related quality of life (OHRQoL) with the OHIP-G14, the Mini-Mental Status (MMS) and Mini Nutritional Assessment (MNA). Six months after implantation and prosthetic rehabilitation, individual nutritional counseling was performed by a dietician. Data were again collected and analyzed. A final follow-up was conducted 12 months after prosthetic rehabilitation. Results Despite the highly significant improvement in masticatory ability and OHRQoL after implant-prosthetic rehabilitation, no significant changes were observed regarding MNA, anthropometric data or energy supply. Except for cholinesterase (p = 0.012), ferritin (p = 0.003), folic acid (p = 0.019) and vitamin A (p = 0.004), no laboratory parameter changed significantly during the investigation period. In addition, no general significant differences were observed for nutrient intake or food choice. Conclusion The present study does not confirm the assumption that the implant-prosthetic rehabilitation of patients with severely reduced residual dentitions with or without an individual nutritional counseling influences nutritional status. PMID:26821352

Pilot Study on the Influence of Nutritional Counselling and Implant Therapy on the Nutritional Status in Dentally Compromised Patients.

PubMed

Wöstmann, Bernd; Simon, Teresa; Neuhäuser-Berthold, Monika; Rehmann, Peter

2016-01-01

To investigate the impact of implant-prosthetic rehabilitation combined with nutritional counseling on the nutritional status of patients with severely reduced dentitions. An explorative intervention study including an intra-individual comparison of 20 patients with severely reduced dentitions in terms of nutrition- and quality of life-related parameters recorded at baseline and at six and twelve months after implant-prosthetic rehabilitation. Twenty patients from the Department of Prosthetic Dentistry of Justus-Liebig University of Giessen, with an mean age of 63 years, who had fewer than ten pairs of antagonists. The baseline data collection included dental status, a chewing ability test, laboratory parameters, anthropometric data (body mass index), energy supply, a 3-day dietary record, an analysis of the oral health-related quality of life (OHRQoL) with the OHIP-G14, the Mini-Mental Status (MMS) and Mini Nutritional Assessment (MNA). Six months after implantation and prosthetic rehabilitation, individual nutritional counseling was performed by a dietician. Data were again collected and analyzed. A final follow-up was conducted 12 months after prosthetic rehabilitation. Despite the highly significant improvement in masticatory ability and OHRQoL after implant-prosthetic rehabilitation, no significant changes were observed regarding MNA, anthropometric data or energy supply. Except for cholinesterase (p = 0.012), ferritin (p = 0.003), folic acid (p = 0.019) and vitamin A (p = 0.004), no laboratory parameter changed significantly during the investigation period. In addition, no general significant differences were observed for nutrient intake or food choice. The present study does not confirm the assumption that the implant-prosthetic rehabilitation of patients with severely reduced residual dentitions with or without an individual nutritional counseling influences nutritional status.

Prosthetists' and Orthotists' experience of their work and workspace - characterising the physical and organisational environment: Focus group findings.

PubMed

Anderson, Sarah; Stuckey, Rwth; Oakman, Jodi R

2016-12-01

Little research has been undertaken into occupational health and safety in the Prosthetics and Orthotics profession. To identify physical, psychosocial and environmental workplace experiences of Prosthetists and Orthotists in organisational settings. Qualitative methodology, cross-sectional design, using thematically analysed data collected from focus groups. Focus groups explored workplace and work experiences across varied Prosthetic and Orthotic settings. Data were thematically analysed to identify physical, psychosocial and environmental workplace experiences. Three major themes, Demands of Work Practice, Impacts on the Individual and Job Design, were identified as problematic. A latent theme Perceptions of Others of P&O highlighted a lack of understanding of the Prosthetics and Orthotics job role outside the profession. This first study of occupational health and safety in the Prosthetics and Orthotics profession identifies a number of important physical and psychosocial issues, including characteristics that have been previously identified as risk factors for work-related musculoskeletal disorders. Findings from the study indicate that some Australian organisations lack understanding of the Prosthetics and Orthotics job role, which results in inappropriate expectations of Prosthetics and Orthotics professionals. Preventing injuries and retaining experienced Prosthetists and Orthotists in the workplace is vital for the profession, and as a result, issues raised in this study require further exploration and then development of appropriate management strategies. This is the first study characterising the experiences of work and risk of injuries in Prosthetists and Orthotists. Preventing injuries and retaining experienced Prosthetists and Orthotists in the workplace is vital for the international profession. Issues raised in this study require further exploration and then development of appropriate management strategies. © The International Society for Prosthetics and Orthotics 2015.

Oral health-related quality of life after prosthetic rehabilitation in patients with oral cancer: A longitudinal study with the Liverpool Oral Rehabilitation Questionnaire version 3 and Oral Health Impact Profile-14 questionnaire.

PubMed

Dholam, K P; Chouksey, G C; Dugad, J

2016-01-01

Prosthodontic rehabilitation helps to improve the oral health-related quality of life (OHRQOL). The Liverpool Oral Rehabilitation Questionnaire (LORQ) and Oral Health Impact Profile (OHIP) are specific tools that measure OHRQOL. The primary objective of this study was to assess the impact of oral rehabilitation on patients' OHRQOL following treatment for cancer of oral cavity using LORQ version 3 (LORQv3) and OHIP-14 questionnaire. Secondary objectives were to identify issues specific to oral rehabilitation, patients compliance to prosthetic rehabilitation, the effect of radiation treatment on prosthetic rehabilitation, to achieve meaningful differences over a time before & after prosthetic intervention, to carryout and document specific patient-deprived problem. Seventy-five oral cancer patients were studied. Patients were asked to rate their experience of dental problems before fabrication of prosthesis and after 1 year using LORQv3 and OHIP-14. The responses were compared on Likert scale. Patients reported with extreme problems before rehabilitation. After 1 year of prosthetic rehabilitation, there was improvement noticed in all the domain of LORQv3 and OHIP-14. Complete compliance to the use of prosthetic appliances for 1 year study period was noted. In response to the question no. 40 (LORQv3), only 15 patients who belonged to the obturator group, brought to notice the problems which were not addressed in the LORQv3 questionnaire. The study showed that the oral cancer patients coped well and adapted to near normal oral status after prosthetic rehabilitation. This contributed to the improved overall health-related quality of life.

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

PubMed

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.

Electric toothbrushes induce electric current in fixed dental appliances by creating magnetic fields.

PubMed

Kameda, Takashi; Ohkuma, Kazuo; Ishii, Nozomu; Sano, Natsuki; Ogura, Hideo; Terada, Kazuto

2012-01-01

Magnetic fields can represent a health problem, especially low frequency electromagnetic fields sometimes induced by electric current in metallic objects worn or used in or on the body (as opposed to high frequency electromagnetic fields that produce heat). Electric toothbrushes are widely used because of their convenience, but the electric motors that power them may produce electromagnetic waves. In this study, we showed that electric toothbrushes generate low frequency (1-2000 Hz) magnetic fields and induce electric current in dental appliances (e. g. orthodontic and prosthetic appliances and dental implants). Current induced by electric toothbrushes might be dependent on the quantity and types of metals used, and the shape of the appliances. Furthermore, these induced currents in dental appliances could impact upon human oral health, producing pain and discomfort.

Contact dermatitis to cobalt chloride with an unusual mechanism.

PubMed

Arslan, Sevket; Aksan, Serkan; Ucar, Ramazan; Caliskaner, Ahmet Zafer

2015-10-01

Contact dermatitis is a frequent inflammatory skin disease. A suspected diagnosis is based on clinical symptoms, a plausible contact to allergens and a suitable history of dermatitis. Therefore, careful diagnosis by patch testing is of great importance because the patch testing is important to find out which allergen/material causes the complaints. Metallic allergens such as cobalt are among the most common causes of allergic contact dermatitis, but frequencies of contact dermatitis to these allergens may vary in different skin areas. Here, we report an unusual case of cobalt allergy on the skin contact with the prosthetic leg of a 30-year-old female patient. The patient developed maculopapular and vesicular lesions on her contact region of residual limb to prosthetic leg. She underwent standard patch testing, which resulted in a strong positive reaction to cobalt chloride. This case report may serve to remind doctors to be aware of potential allergic reactions to prostheses and to enable them to recognize a metal allergy if it appears. Prosthetists should also be reminded of potential allergic reactions. Cobalt can be used as an accelerator in making a prosthetic socket. Several cases have been reported concerning allergies to components of the prosthetic socket. This is the first report of sensitization to cobalt which is used in making a prosthetic leg. © The International Society for Prosthetics and Orthotics 2014.

The Effects of the Inertial Properties of Above-Knee Prostheses on Optimal Stiffness, Damping, and Engagement Parameters of Passive Prosthetic Knees.

PubMed

Narang, Yashraj S; Murthy Arelekatti, V N; Winter, Amos G

2016-12-01

Our research aims to design low-cost, high-performance, passive prosthetic knees for developing countries. In this study, we determine optimal stiffness, damping, and engagement parameters for a low-cost, passive prosthetic knee that consists of simple mechanical elements and may enable users to walk with the normative kinematics of able-bodied humans. Knee joint power was analyzed to divide gait into energy-based phases and select mechanical components for each phase. The behavior of each component was described with a polynomial function, and the coefficients and polynomial order of each function were optimized to reproduce the knee moments required for normative kinematics of able-bodied humans. Sensitivity of coefficients to prosthesis mass was also investigated. The knee moments required for prosthesis users to walk with able-bodied normative kinematics were accurately reproduced with a mechanical system consisting of a linear spring, two constant-friction dampers, and three clutches (R2=0.90 for a typical prosthetic leg). Alterations in upper leg, lower leg, and foot mass had a large influence on optimal coefficients, changing damping coefficients by up to 180%. Critical results are reported through parametric illustrations that can be used by designers of prostheses to select optimal components for a prosthetic knee based on the inertial properties of the amputee and his or her prosthetic leg.

Optical fiber Bragg grating-instrumented silicone liner for interface pressure measurement within prosthetic sockets of lower-limb amputees

NASA Astrophysics Data System (ADS)

Al-Fakih, Ebrahim; Arifin, Nooranida; Pirouzi, Gholamhossein; Mahamd Adikan, Faisal Rafiq; Shasmin, Hanie Nadia; Abu Osman, Noor Azuan

2017-08-01

This paper presents a fiber Bragg grating (FBG)-instrumented prosthetic silicone liner that provides cushioning for the residual limb and can successfully measure interface pressures inside prosthetic sockets of lower-limb amputees in a simple and practical means of sensing. The liner is made of two silicone layers between which 12 FBG sensors were embedded at locations of clinical interest. The sensors were then calibrated using a custom calibration platform that mimics a real-life situation. Afterward, a custom gait simulating machine was built to test the liner performance during an amputee's simulated gait. To validate the findings, the results were compared to those obtained by the commonly used F-socket mats. As the statistical findings reveal, both pressure mapping methods measured the interface pressure in a consistent way, with no significant difference (P-values ≥0.05). This pressure mapping technique in the form of a prosthetic liner will allow prosthetics professionals to quickly and accurately create an overall picture of the interface pressure distribution inside sockets in research and clinical settings, thereby improving the socket fit and amputee's satisfaction.

The Effect of the Prosthetic Group on the Pharmacologic Properties of 18F-labeled Rhodamine B, a Potential Myocardial Perfusion Agent for PET

PubMed Central

Bartholomä, Mark D.; Gottumukkala, Vijay; Zhang, Shaohui; Baker, Amanda; Dunning, Patricia; Fahey, Frederic H.; Treves, S. Ted; Packard, Alan B.

2013-01-01

We recently reported the development of the 2-[18F]fluoroethyl ester of rhodamine B as a potential positron emission tomography (PET) tracer for myocardial perfusion imaging. This compound, which was prepared using a [18F]fluoroethyl prosthetic group, has significant uptake in the myocardium in rats, but also demonstrates relatively high liver uptake and is rapidly hydrolyzed in vivo in mice. We have now prepared 18F-labeled rhodamine B using three additional prosthetic groups (propyl, diethylene glycol, and triethylene glycol) and found that the prosthetic group has a significant effect on the in vitro and in vivo properties of these compounds. Of the esters prepared to date, the diethylene glycol ester is superior in terms of in vitro stability and pharmacokinetics. These observations suggest that the prosthetic group plays a significant role in determining the pharmacological properties of 18F-labeled compounds. They also support the value of continued investigation of 18F-labeled rhodamines as PET radiopharmaceuticals for myocardial perfusion imaging. PMID:23210516

Effect of the prosthetic group on the pharmacologic properties of 18F-labeled rhodamine B, a potential myocardial perfusion agent for positron emission tomography (PET).

PubMed

Bartholomä, Mark D; Gottumukkala, Vijay; Zhang, Shaohui; Baker, Amanda; Dunning, Patricia; Fahey, Frederic H; Treves, S Ted; Packard, Alan B

2012-12-27

We recently reported the development of the 2-[(18)F]fluoroethyl ester of rhodamine B as a potential positron emission tomography (PET) tracer for myocardial perfusion imaging. This compound, which was prepared using a [(18)F]fluoroethyl prosthetic group, has significant uptake in the myocardium in rats but also demonstrates relatively high liver uptake and is rapidly hydrolyzed in vivo in mice. We have now prepared (18)F-labeled rhodamine B using three additional prosthetic groups (propyl, diethylene glycol, and triethylene glycol) and found that the prosthetic group has a significant effect on the in vitro and in vivo properties of these compounds. Of the esters prepared to date, the diethylene glycol ester is superior in terms of in vitro stability and pharmacokinetics. These observations suggest that the prosthetic group plays a significant role in determining the pharmacological properties of (18)F-labeled compounds. They also support the value of continued investigation of (18)F-labeled rhodamines as PET radiopharmaceuticals for myocardial perfusion imaging.

Overproduction in Escherichia coli and Characterization of a Soybean Ferric Leghemoglobin Reductase.

PubMed Central

Ji, L.; Becana, M.; Sarath, G.; Shearman, L.; Klucas, R. V.

1994-01-01

We previously cloned and sequenced a cDNA encoding soybean ferric leghemoglobin reductase (FLbR), an enzyme postulated to play an important role in maintaining leghemoglobin in a functional ferrous state in nitrogen-fixing root nodules. This cDNA was sub-cloned into an expression plasmid, pTrcHis C, and overexpressed in Escherichia coli. The recombinant FLbR protein, which was purified by two steps of column chromatography, was catalytically active and fully functional. The recombinant FLbR cross-reacted with antisera raised against native FLbR purified from soybean root nodules. The recombinant FLbR, the native FLbR purified from soybean (Glycine max L.) root nodules, and dihydrolipoamide dehydrogenases from pig heart and yeast had similar but not identical ultraviolet-visible absorption and fluorescence spectra, cofactor binding, and kinetic properties. FLbR shared common structural features in the active site and prosthetic group binding sites with other pyridine nucleotide-disulfide oxidoreductases such as dihydrolipoamide dehydrogenases, but displayed different microenvironments for the prosthetic groups. PMID:12232320

Rapid control and feedback rates enhance neuroprosthetic control

PubMed Central

Shanechi, Maryam M.; Orsborn, Amy L.; Moorman, Helene G.; Gowda, Suraj; Dangi, Siddharth; Carmena, Jose M.

2017-01-01

Brain-machine interfaces (BMI) create novel sensorimotor pathways for action. Much as the sensorimotor apparatus shapes natural motor control, the BMI pathway characteristics may also influence neuroprosthetic control. Here, we explore the influence of control and feedback rates, where control rate indicates how often motor commands are sent from the brain to the prosthetic, and feedback rate indicates how often visual feedback of the prosthetic is provided to the subject. We developed a new BMI that allows arbitrarily fast control and feedback rates, and used it to dissociate the effects of each rate in two monkeys. Increasing the control rate significantly improved control even when feedback rate was unchanged. Increasing the feedback rate further facilitated control. We also show that our high-rate BMI significantly outperformed state-of-the-art methods due to higher control and feedback rates, combined with a different point process mathematical encoding model. Our BMI paradigm can dissect the contribution of different elements in the sensorimotor pathway, providing a unique tool for studying neuroprosthetic control mechanisms. PMID:28059065

State-space control of prosthetic hand shape.

PubMed

Velliste, M; McMorland, A J C; Diril, E; Clanton, S T; Schwartz, A B

2012-01-01

In the field of neuroprosthetic control, there is an emerging need for simplified control of high-dimensional devices. Advances in robotic technology have led to the development of prosthetic arms that now approach the look and number of degrees of freedom (DoF) of a natural arm. These arms, and especially hands, now have more controllable DoFs than the number of control DoFs available in many applications. In natural movements, high correlations exist between multiple joints, such as finger flexions. Therefore, discrepancy between the number of control and effector DoFs can be overcome by a control scheme that maps low-DoF control space to high-DoF joint space. Imperfect effectors, sensor noise and interactions with external objects require the use of feedback controllers. The incorporation of feedback in a system where the command is in a different space, however, is challenging, requiring a potentially difficult inverse high-DoF to low-DoF transformation. Here we present a solution to this problem based on the Extended Kalman Filter.

Rapid control and feedback rates enhance neuroprosthetic control

NASA Astrophysics Data System (ADS)

Shanechi, Maryam M.; Orsborn, Amy L.; Moorman, Helene G.; Gowda, Suraj; Dangi, Siddharth; Carmena, Jose M.

2017-01-01

Brain-machine interfaces (BMI) create novel sensorimotor pathways for action. Much as the sensorimotor apparatus shapes natural motor control, the BMI pathway characteristics may also influence neuroprosthetic control. Here, we explore the influence of control and feedback rates, where control rate indicates how often motor commands are sent from the brain to the prosthetic, and feedback rate indicates how often visual feedback of the prosthetic is provided to the subject. We developed a new BMI that allows arbitrarily fast control and feedback rates, and used it to dissociate the effects of each rate in two monkeys. Increasing the control rate significantly improved control even when feedback rate was unchanged. Increasing the feedback rate further facilitated control. We also show that our high-rate BMI significantly outperformed state-of-the-art methods due to higher control and feedback rates, combined with a different point process mathematical encoding model. Our BMI paradigm can dissect the contribution of different elements in the sensorimotor pathway, providing a unique tool for studying neuroprosthetic control mechanisms.

A review of extra-articular prosthetic stabilization of the cranial cruciate ligament-deficient stifle.

PubMed

Tonks, C A; Lewis, D D; Pozzi, A

2011-01-01

Extra-articular prosthetic stabilization techniques have been used as a method of stabilization of the cranial cruciate ligament (CrCL)-deficient stifle for decades. During extra-articular prosthetic stabilization, the prosthesis is anchored to the femur and tibia, and tensioned in the attempt to resolve femorotibial instability. The position of the anchor points of the prosthesis is crucial for restoring a normal range of joint motion and mitigating alterations in prosthesis tension during motion. Recently developed techniques offer several innovations with potential advantages such as bone-to-bone fixation, prosthetic materials with better mechanical properties, and improved isometry of the anchor points. Whether these innovations provide clinically superior results to the traditional techniques such as lateral circumfabellar-tibial suture techniques has yet to be determined.

[Localized purpura revealing vascular prosthetic graft infection].

PubMed

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.

Toward more versatile and intuitive cortical brain machine interfaces

PubMed Central

Andersen, Richard A.; Kellis, Spencer; Klaes, Christian; Aflalo, Tyson

2015-01-01

Brain machine interfaces have great potential in neuroprosthetic applications to assist patients with brain injury and neurodegenerative diseases. One type of BMI is a cortical motor prosthetic which is used to assist paralyzed subjects. Motor prosthetics to date have typically used the motor cortex as a source of neural signals for controlling external devices. The review will focus on several new topics in the arena of cortical prosthetics. These include using 1) recordings from cortical areas outside motor cortex; 2) local field potentials (LFPs) as a source of recorded signals; 3) somatosensory feedback for more dexterous control of robotics; and 4) new decoding methods that work in concert to form an ecology of decode algorithms. These new advances hold promise in greatly accelerating the applicability and ease of operation of motor prosthetics. PMID:25247368

Fluid mechanics of heart valves.

PubMed

Yoganathan, Ajit P; He, Zhaoming; Casey Jones, S

2004-01-01

Valvular heart disease is a life-threatening disease that afflicts millions of people worldwide and leads to approximately 250,000 valve repairs and/or replacements each year. Malfunction of a native valve impairs its efficient fluid mechanic/hemodynamic performance. Artificial heart valves have been used since 1960 to replace diseased native valves and have saved millions of lives. Unfortunately, despite four decades of use, these devices are less than ideal and lead to many complications. Many of these complications/problems are directly related to the fluid mechanics associated with the various mechanical and bioprosthetic valve designs. This review focuses on the state-of-the-art experimental and computational fluid mechanics of native and prosthetic heart valves in current clinical use. The fluid dynamic performance characteristics of caged-ball, tilting-disc, bileaflet mechanical valves and porcine and pericardial stented and nonstented bioprostheic valves are reviewed. Other issues related to heart valve performance, such as biomaterials, solid mechanics, tissue mechanics, and durability, are not addressed in this review.

Dosimetric considerations for patients with HIP prostheses undergoing pelvic irradiation. Report of the AAPM Radiation Therapy Committee Task Group 63.

PubMed

Reft, Chester; Alecu, Rodica; Das, Indra J; Gerbi, Bruce J; Keall, Paul; Lief, Eugene; Mijnheer, Ben J; Papanikolaou, Nikos; Sibata, Claudio; Van Dyk, Jake

2003-06-01

This document is the report of a task group of the Radiation Therapy Committee of the AAPM and has been prepared primarily to advise hospital physicists involved in external beam treatment of patients with pelvic malignancies who have high atomic number (Z) hip prostheses. The purpose of the report is to make the radiation oncology community aware of the problems arising from the presence of these devices in the radiation beam, to quantify the dose perturbations they cause, and, finally, to provide recommendations for treatment planning and delivery. Some of the data and recommendations are also applicable to patients having implanted high-Z prosthetic devices such as pins, humeral head replacements. The scientific understanding and methodology of clinical dosimetry for these situations is still incomplete. This report is intended to reflect the current state of scientific understanding and technical methodology in clinical dosimetry for radiation oncology patients with high-Z hip prostheses.

Simulation of personalised haemodynamics by various mounting positions of a prosthetic valve using computational fluid dynamics.

PubMed

Bongert, Markus; Geller, Marius; Pennekamp, Werner; Nicolas, Volkmar

2018-03-03

Diseases of the cardiovascular system account for nearly 42% of all deaths in the European Union. In Germany, approximately 12,000 patients receive surgical replacement of the aortic valve due to heart valve disease alone each year. A three-dimensional (3D) numerical model based on patient-specific anatomy derived from four-dimensional (4D) magnetic resonance imaging (MRI) data was developed to investigate preoperatively the flow-induced impact of mounting positions of aortic prosthetic valves to select the best orientation for individual patients. Systematic steady-state analysis of blood flow for different rotational mounting positions of the valve is only possible using a virtual patient model. A maximum velocity of 1 m/s was used as an inlet boundary condition, because the opening angle of the valve is at its largest at this velocity. For a comparative serial examination, it is important to define the standardised general requirements to avoid impacts other than the rotated implantation of the prosthetic aortic valve. In this study, a uniform velocity profile at the inlet for the inflow of the aortic valve and the real aortic anatomy were chosen for all simulations. An iterative process, with the weighted parameters flow resistance (1), shear stress (2) and velocity (3), was necessary to determine the best rotated orientation. Blood flow was optimal at a 45° rotation from the standard implantation orientation, which will offer a supply to the coronary arteries.

Do Prolonged Prophylactic Antibiotics Reduce the Incidence of Surgical-Site Infections in Immediate Prosthetic Breast Reconstruction?

PubMed

Wang, Frederick; Chin, Robin; Piper, Merisa; Esserman, Laura; Sbitany, Hani

2016-12-01

Approximately 50,000 women in the United States undergo mastectomy and immediate prosthetic breast reconstruction annually, and most receive postoperative prophylactic antibiotics. The effect of these antibiotics on the risk of surgical-site infections remains unclear. The authors searched the Medline, Embase, and Cochrane Library databases for studies that compared less than 24 hours and greater than 24 hours of antibiotics following immediate prosthetic breast reconstruction. Primary outcomes were surgical-site infections and implant loss. Conservative random effects models were used to obtain pooled relative risk estimates. The authors identified 927 studies, but only four cohort studies and one randomized controlled trial met their inclusion criteria. Unadjusted incidences of surgical-site infections were 14 percent with more than 24 hours of antibiotics, 19 percent with less than 24 hours of antibiotics, and 16 percent overall. Unadjusted incidences of implant loss were 8 percent with more than 24 hours of antibiotics, 10 percent with less than 24 hours of antibiotics, and 9 percent overall. The pooled relative risk of implant loss was 1.17 (95 percent CI, 0.39 to 3.6) with less than 24 hours of antibiotics, which was not statistically significant. Prolonged antibiotic use did not have a statistically significant effect on reducing surgical-site infections or implant loss. There was significant heterogeneity between studies, and prolonged antibiotics may have increased the risk of implant loss in the randomized controlled trial. Definitive evidence may only be obtained with data from more prospective randomized controlled trials.

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

DTIC Science & Technology

2015-10-01

Modulated Sensory Feedback from, a Hand Prosthesis PRINCIPAL INVESTIGATOR: Bradley Greger, PhD CONTRACTING ORGANIZATION: Arizona State University...Residual Peripheral Nerves to Provide Dextrous Control of, and Modulated Sensory Feedback from, a Hand Prosthesis 5a. CONTRACT NUMBER 5b. GRANT...Peripheral Nerve Interface, Prosthetic Hand, Neural Prosthesis , Sensory Feedback, Micro-stimulation, Electrophysiology, Action Potentials, Micro

Amputation and Prosthetics

MedlinePlus

... Extremity Prosthetics Find a hand surgeon near you. Videos Figures Figure 1: Thumb Prosthesis - not attached Figure ... or "in." Also, avoid using media types like "video," "article," and "picture." Tip 4: Your results can ...

Rotational joint assembly for the prosthetic leg

NASA Technical Reports Server (NTRS)

Owens, L. J.; Jones, W. C. (Inventor)

1977-01-01

A rotational joint assembly for a prosthetic leg has been devised, which enables an artificial foot to rotate slightly when a person is walking, running or turning. The prosthetic leg includes upper and lower tubular members with the rotational joint assembly interposed between them. The assembly includes a restrainer mechanism which consists of a pivotably mounted paddle element. This device applies limiting force to control the rotation of the foot and also restores torque to return the foot back to its initial position.

A radiograph positioning technique to evaluate prosthetic misfit and bone loss around implants.

PubMed

Lin, Kevin C; Wadhwani, Chandur P K; Sharma, Arun; Finzen, Frederick

2014-02-01

A radiograph positioning device was developed to fit with commercially available film holders and implant systems. The device is indexed to the dental implant body and the adjacent dentition by using an implant placement driver and polyvinyl siloxane occlusal registration material. By fitting the device to a conventional film holder, accurate orthogonal radiographs can monitor changes in bone architecture and prosthetic misfit. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

A personalized 3D-printed prosthetic joint replacement for the human temporomandibular joint: From implant design to implantation.

PubMed

Ackland, David C; Robinson, Dale; Redhead, Michael; Lee, Peter Vee Sin; Moskaljuk, Adrian; Dimitroulis, George

2017-05-01

Personalized prosthetic joint replacements have important applications in cases of complex bone and joint conditions where the shape and size of off-the-shelf components may not be adequate. The objective of this study was to design, test and fabricate a personalized 3D-printed prosthesis for a patient requiring total joint replacement surgery of the temporomandibular joint (TMJ). The new 'Melbourne' prosthetic TMJ design featured a condylar component sized specifically to the patient and fixation screw positions that avoid potential intra-operative damage to the mandibular nerve. The Melbourne prosthetic TMJ was developed for a 58-year-old female recipient with end-stage osteoarthritis of the TMJ. The load response of the prosthesis during chewing and a maximum-force bite was quantified using a personalized musculoskeletal model of the patient's masticatory system developed using medical images. The simulations were then repeated after implantation of the Biomet Microfixation prosthetic TMJ, an established stock device. The maximum condylar stresses, screw stress and mandibular stress at the screw-bone interface were lower in the Melbourne prosthetic TMJ (259.6MPa, 312.9MPa and 198.4MPa, respectively) than those in the Biomet Microfixation device (284.0MPa, 416.0MPa and 262.2MPa, respectively) during the maximum-force bite, with similar trends also observed during the chewing bite. After trialing surgical placement and evaluating prosthetic TMJ stability using cadaveric specimens, the prosthesis was fabricated using 3D printing, sterilized, and implanted into the female recipient. Six months post-operatively, the prosthesis recipient had a normal jaw opening distance (40.0 mm), with no complications identified. The new design features and immediate load response of the Melbourne prosthetic TMJ suggests that it may provide improved clinical and biomechanical joint function compared to a commonly used stock device, and reduce risk of intra-operative nerve damage during placement. The framework presented may be useful for designing and testing customized devices for the treatment of debilitating bone and joint conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Rehabilitation and the Veterans' Administration

NASA Technical Reports Server (NTRS)

Meister, F.

1974-01-01

The Veteran's Administration health care system provides prosthetic and sensory aids for the rehabilitation of neurologically handicapped veterans. Research and development centers include prosthetic clinic teams, orthopedic shops, restoration clinics, bioengineering services, orthotics, etc.

75 FR 16511 - Pentron Clinical Technologies, a Wholly-Owned Subsidiary of Kerr Dental/Sybron Dental...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-01

... produce dental materials such as dental prosthetics, dental composites, dental impressions, dental... materials such as dental prosthetics, dental composites, dental impressions, dental adhesives, and other...

78 FR 48941 - Advisory Committee on Prosthetics and Special-Disabilities Programs, Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-12

...- art prosthetics and the associated rehabilitation research, development, and evaluation of such..., blindness or visual impairments, loss of extremities or loss of function, deafness or hearing impairment...

Toward more versatile and intuitive cortical brain-machine interfaces.

PubMed

Andersen, Richard A; Kellis, Spencer; Klaes, Christian; Aflalo, Tyson

2014-09-22

Brain-machine interfaces have great potential for the development of neuroprosthetic applications to assist patients suffering from brain injury or neurodegenerative disease. One type of brain-machine interface is a cortical motor prosthetic, which is used to assist paralyzed subjects. Motor prosthetics to date have typically used the motor cortex as a source of neural signals for controlling external devices. The review will focus on several new topics in the arena of cortical prosthetics. These include using: recordings from cortical areas outside motor cortex; local field potentials as a source of recorded signals; somatosensory feedback for more dexterous control of robotics; and new decoding methods that work in concert to form an ecology of decode algorithms. These new advances promise to greatly accelerate the applicability and ease of operation of motor prosthetics. Copyright © 2014 Elsevier Ltd. All rights reserved.

Remote monitoring of lower-limb prosthetic socket fit using wireless technologies.

PubMed

Sahandi, R; Sewell, P; Noroozi, S; Hewitt, M

2012-01-01

Accurate fitting of a lower-limb prosthetic socket is the most important factor affecting amputee satisfaction and rehabilitation. The technology is now available to allow real-time monitoring of in-service pressure distribution of prosthetic limbs. This paper proposes a remote interfacial pressure monitoring system necessary for the assessment of fit. The suitability of a wireless ZigBee network due to its relevant technical specification is investigated. The system enables remote monitoring of a prosthetic socket and its fit under different operating conditions thereby improving design, efficiency and effectiveness. The data can be used by prosthetists and may also be recorded for future training or for patient progress monitoring. This can minimize the number of iterations by getting it right first time, thereby minimizing the number of replacement prostheses. Copyright © 2012 Informa UK, Ltd.

[Microbiological characteristics and patterns of resistance in prosthetic joint infections in a referral hospital].

PubMed

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.

The effects of prosthetic foot roll-over shape arc length on the gait of trans-tibial prosthesis users.

PubMed

Hansen, Andrew H; Meier, Margrit R; Sessoms, Pinata H; Childress, Dudley S

2006-12-01

The Shape&Roll prosthetic foot was used to examine the effect of roll-over shape arc length on the gait of 14 unilateral trans-tibial prosthesis users. Simple modifications to the prosthetic foot were used to alter the effective forefoot rocker length, leaving factors such as alignment, limb length, and heel and mid-foot characteristics unchanged. Shortening the roll-over shape arc length caused a significant reduction in the maximum external dorsiflexion moment on the prosthetic side at all walking speeds (p < 0.001 for main effect of arc length), due to a reduction in forefoot leverage (moment arm) about the ankle. Roll-over shape arc length significantly affected the initial loading on the sound limb at normal and fast speeds (p = 0.001 for the main effect of arc length), with participants experiencing larger first peaks of vertical ground reaction forces on their sound limbs when using the foot with the shortest effective forefoot rocker arc length. Additionally, the difference between step lengths on the sound and prosthetic limbs was larger with the shortest arc length condition, although this difference was not statistically significant (p = 0.06 for main effect). It appears that prosthesis users may experience a drop-off effect at the end of single limb stance on prosthetic feet with short roll-over shape arc lengths, leading to increased loading and/or a shortened step on the contralateral limb.

ECONOMIC EVALUATIONS OF INTERVENTIONS FOR TRANSTIBIAL AMPUTEES: A SCOPING REVIEW OF COMPARATIVE STUDIES.

PubMed

Highsmith, M Jason; Kahle, Jason T; Lewandowski, Amanda; Klenow, Tyler D; Orriola, John J; Miro, Rebecca M; Hill, Owen T; Raschke, Sylvia Ursula; Orendurff, Michael S; Highsmith, James T; Sutton, Bryce S

2016-09-01

Transtibial amputation (TTA) is life-altering emotionally, functionally, and economically. The economic impact to all stakeholders is largely unknown, as is the cost-effectiveness of prosthetic intervention. This scoping report's purpose was to determine if there is sufficient evidence to conduct a formal systematic review or meta-analysis in any particular prosthetic intervention area and to determine if any evidence statements could be synthesized relative to economic evaluation of interventions provided to patients with TTA. The scoping review revealed six articles representing three topical areas of transtibial care: Care Models, Prosthetic Treatment, and Prosthetic Sockets. All six articles were cost-identification or cost-consequence design and included a total of 704 subjects. Presently, it can be concluded with moderate confidence that specific weight-bearing and total-contact sockets for transtibial amputees are functionally and economically equivalent in the short term when costs, delivery time, and all stakeholder perspectives are considered. Long-term socket outcomes are relatively unexplored. Further primary research is needed beyond this to determine cost-effectiveness for other areas of transtibial prosthetic care although clinical outcomes are somewhat established through systematic review and meta-analysis in other areas of care. Conversely, evaluation of narrative economic reports relative to transtibial care may be sufficient to warrant further analysis. Guidance from the profession may also be useful in devising a strategy for how to assure economic analyses are a routine element of future prosthetic science.

Beyond intuitive anthropomorphic control: recent achievements using brain computer interface technologies

NASA Astrophysics Data System (ADS)

Pohlmeyer, Eric A.; Fifer, Matthew; Rich, Matthew; Pino, Johnathan; Wester, Brock; Johannes, Matthew; Dohopolski, Chris; Helder, John; D'Angelo, Denise; Beaty, James; Bensmaia, Sliman; McLoughlin, Michael; Tenore, Francesco

2017-05-01

Brain-computer interface (BCI) research has progressed rapidly, with BCIs shifting from animal tests to human demonstrations of controlling computer cursors and even advanced prosthetic limbs, the latter having been the goal of the Revolutionizing Prosthetics (RP) program. These achievements now include direct electrical intracortical microstimulation (ICMS) of the brain to provide human BCI users feedback information from the sensors of prosthetic limbs. These successes raise the question of how well people would be able to use BCIs to interact with systems that are not based directly on the body (e.g., prosthetic arms), and how well BCI users could interpret ICMS information from such devices. If paralyzed individuals could use BCIs to effectively interact with such non-anthropomorphic systems, it would offer them numerous new opportunities to control novel assistive devices. Here we explore how well a participant with tetraplegia can detect infrared (IR) sources in the environment using a prosthetic arm mounted camera that encodes IR information via ICMS. We also investigate how well a BCI user could transition from controlling a BCI based on prosthetic arm movements to controlling a flight simulator, a system with different physical dynamics than the arm. In that test, the BCI participant used environmental information encoded via ICMS to identify which of several upcoming flight routes was the best option. For both tasks, the BCI user was able to quickly learn how to interpret the ICMSprovided information to achieve the task goals.

Comparison between microprocessor-controlled ankle/foot and conventional prosthetic feet during stair negotiation in people with unilateral transtibial amputation.

PubMed

Agrawal, Vibhor; Gailey, Robert S; Gaunaurd, Ignacio A; O'Toole, Christopher; Finnieston, Adam A

2013-01-01

Contrary to stance-phase dorsiflexion of conventional prosthetic feet, the microprocessor-controlled Proprio foot permits swing-phase dorsiflexion on stairs. The purpose of this study was to compare Symmetry in External Work (SEW) between a microprocessor-controlled foot and conventional prosthetic feet in two groups with unilateral transtibial amputation (Medicare Functional Classification Levels K-Level-2 and K-Level-3) during stair ascent and descent. Ten subjects were evaluated while wearing three conventional prosthetic feet- solid ankle cushion heel (SACH), stationary attachment flexible endoskeleton (SAFE), and Talux-and the Proprio foot using a study socket and were given a 10- to 14-day accommodation period with each foot. Ground reaction forces were collected using F-scan sensors during stair ascent and descent. The SEW between the intact and amputated limbs was calculated for each foot. During stair ascent, the Proprio foot resulted in a higher interlimb symmetry than conventional prosthetic feet, with significant differences between the Pro prio and SACH/SAFE feet. The swing-phase dorsiflexion appeared to promote greater interlimb symmetry because it facilitated forward motion of the body, resulting in a heel-to-toe center of pressure trajectory. During stair descent, all feet had low symmetry without significant differences between feet. The movement strategy used when descending stairs, which is to roll over the edge of a step, had a greater influence on symmetry than the dorsiflexion features of prosthetic feet.

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

PubMed

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 < 0.05). Sufficient vision penalization can be achieved to make 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.

Prosthetic joint infection caused by Granulicatella adiacens: a case series and review of literature.

PubMed

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.

A fluorescence approach to the unfolding thermodynamics of horseradish peroxidase based on heme degradation by hydrogen peroxide

NASA Astrophysics Data System (ADS)

Ke, Zhigang; Ma, Shanshan; Li, Lamei; Huang, Qing

2016-07-01

Horseradish peroxidase (HRP) is a classical heme-containing protein which has been applied in many fields. The prosthetic group heme in HRP, especially in unfolded state, can react with hydrogen peroxide (H2O2) to produce a fluorescent product with the maximum emission wavelength at 450 nm. Utilizing this emission band as a fluorescence probe, the unfolding process of HRP in urea can be assessed quantitatively, and the calculated thermodynamic parameters are consistent with those determined by circular dichroism (CD) at 222 nm and steady-state tryptophan (Trp) fluorescence methods.

Optical fiber Bragg grating-instrumented silicone liner for interface pressure measurement within prosthetic sockets of lower-limb amputees.

PubMed

Al-Fakih, Ebrahim; Arifin, Nooranida; Pirouzi, Gholamhossein; Mahamd Adikan, Faisal Rafiq; Shasmin, Hanie Nadia; Abu Osman, Noor Azuan

2017-08-01

This paper presents a fiber Bragg grating (FBG)-instrumented prosthetic silicone liner that provides cushioning for the residual limb and can successfully measure interface pressures inside prosthetic sockets of lower-limb amputees in a simple and practical means of sensing. The liner is made of two silicone layers between which 12 FBG sensors were embedded at locations of clinical interest. The sensors were then calibrated using a custom calibration platform that mimics a real-life situation. Afterward, a custom gait simulating machine was built to test the liner performance during an amputee's simulated gait. To validate the findings, the results were compared to those obtained by the commonly used F-socket mats. As the statistical findings reveal, both pressure mapping methods measured the interface pressure in a consistent way, with no significant difference (P-values ≥0.05). This pressure mapping technique in the form of a prosthetic liner will allow prosthetics professionals to quickly and accurately create an overall picture of the interface pressure distribution inside sockets in research and clinical settings, thereby improving the socket fit and amputee's satisfaction. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

Incidence, severity, and impact of hyperhidrosis in people with lower-limb amputation.

PubMed

Hansen, Colby; Godfrey, Bradeigh; Wixom, Jody; McFadden, Molly

2015-01-01

To assess the incidence and severity of self-reported hyperhidrosis in patients with amputation and understand its effects on prosthetic fit or function, a cross-sectional survey of patients at two amputee clinics was performed. Responses from 121 subjects with lower-limb amputation were analyzed. Of these subjects, 66% reported sweating to a degree that it interfered with daily activities, as measured by the Hyperhidrosis Disease Severity Scale. There was a significant association between sweating and interference with prosthetic fit and function. Sweating was more severe in cases of transtibial amputations, patients under the age of 60, warm weather, and vigorous activity. There was no relationship between severity of sweating and time since amputation, etiology of amputation, duration of daily prosthetic use, or reported ability to perform functional tasks. Subjects reported trying multiple interventions, but the self-reported effectiveness of these treatments was low. Hyperhidrosis, a common problem associated with prosthetic usage, varies in severity and often interferes with daily activities. Sweating severity is associated with poor prosthetic fit and function. Risk factors include younger age and transtibial amputation status. Treatment strategies generally lack efficacy. The results of this study may provide guidance for future interventions and treatment options.

Device to monitor sock use in people using prosthetic limbs: technical report.

PubMed

Sanders, Joan E; Murthy, Revathi; Cagle, John C; Allyn, Katheryn J; Phillips, Reid H; Otis, Brian P

2012-01-01

A device using radio frequency identification (RFID) technology was developed to continuously monitor sock use in people who use prosthetic limbs. RFID tags were placed on prosthetic socks worn by subjects with transtibial limb loss, and a high-frequency RFID reader and antenna were placed in a portable unit mounted to the outside of the prosthetic socket. Bench testing showed the device to have a maximum read range between 5.6 cm and 12.7 cm, depending on the RFID tag used. Testing in a laboratory setting on three participants with transtibial amputation showed that the device correctly monitored sock presence during sitting, standing, and walking activity when one or two socks were worn but was less reliable when more socks were used. Accurate detection was sensitive to orientation of the tag relative to the reader, presence of carbon fiber in the prosthetic socket, pistoning of the limb in the socket, and overlap among the tags. Use of ultra-high-frequency RFID may overcome these limitations. With improvements, the technology may prove useful to practitioners prescribing volume accommodation strategies for patients by providing information about sock use between clinical visits, including timing and consistency of daily sock-ply changes.

Technical Report: A device to monitor sock use on people using prosthetic limbs

PubMed Central

Sanders, Joan; Murthy, Revathi; Cagle, John; Allyn, Katheryn; Phillips, Reid

2015-01-01

A device using radio frequency identification technology (RFID) was developed to continuously monitor sock use on people using prosthetic limbs. RFID tags were placed on prosthetic socks worn by subjects with transtibial limb loss, and a high-frequency (HF) RFID reader and antenna were placed in a portable unit mounted to the outside of the prosthetic socket. Bench testing showed the device to have a maximum read range between 5.6 cm and 12.7 cm, depending on the RFID tag used. Testing in a laboratory setting on three participants with transtibial amputation showed that the device correctly monitored sock presence during sitting, standing, and walking activity when one or two socks were worn but was less reliable when more socks were used. Accurate detection was sensitive to orientation of the tag relative to the reader, presence of carbon fiber in the prosthetic socket, pistoning of the limb in the socket, and overlap among the tags. Use of ultra high frequency (UHF) RFID may overcome these limitations. With improvements, the technology may prove useful to practitioners prescribing volume accommodation strategies for patients by providing information about sock use between clinical visits, including timing and consistency of daily sock ply changes. PMID:23341315

Allograft-prosthetic composite reverse total shoulder arthroplasty for reconstruction of proximal humerus tumor resections.

PubMed

King, Joseph J; Nystrom, Lukas M; Reimer, Nickolas B; Gibbs, C Parker; Scarborough, Mark T; Wright, Thomas W

2016-01-01

Proximal humerus reconstructions after resection of tumors are challenging. Early success of the reverse shoulder arthroplasty for reconstructions has recently been reported. The reverse allograft-prosthetic composite offers the advantage of improved glenohumeral stability compared with hemiarthroplasty for proximal humeral reconstructions as it uses the deltoid for stability. This article describes the technique for treating proximal humeral tumors, including preoperative planning, biopsy principles, resection pearls, soft tissue tensioning, and specifics about reconstruction using the reverse allograft-prosthetic composite. Two cases are presented along with the functional outcomes with use of this technique. Biomechanical considerations during reconstruction are reviewed, including techniques to improve the deltoid compression force. Reported instability rates are less with reverse shoulder arthroplasty reconstruction as opposed to hemiarthroplasty or total shoulder arthroplasty reconstructions of tumor resections. Reported functional outcomes are promising for the reverse allograft-prosthetic composite reconstructions, although complications are reported. Reverse allograft-prosthetic composites are a promising option for proximal humeral reconstructions, although nonunion of the allograft-host bone junction continues to be a challenge for this technique. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Design and characterization of a biologically inspired quasi-passive prosthetic ankle-foot.

PubMed

Mooney, Luke M; Lai, Cara H; Rouse, Elliott J

2014-01-01

By design, commonly worn energy storage and release (ESR) prosthetic feet cannot provide biologically realistic ankle joint torque and angle profiles during walking. Additionally, their anthropomorphic, cantilever architecture causes their mechanical stiffness to decrease throughout the stance phase of walking, opposing the known trend of the biological ankle. In this study, the design of a quasi-passive pneumatic ankle-foot prosthesis is detailed that is able to replicate the biological ankle's torque and angle profiles during walking. The prosthetic ankle is comprised of a pneumatic piston, bending spring and solenoid valve. The mechanical properties of the pneumatic ankle prosthesis are characterized using a materials testing machine and the properties are compared to those from a common, passive ESR prosthetic foot. The characterization spanned a range of ankle equilibrium pressures and testing locations beneath the foot, analogous to the location of center of pressure within the stance phase of walking. The pneumatic ankle prosthesis was shown to provide biologically appropriate trends and magnitudes of torque, angle and stiffness behavior, when compared to the passive ESR prosthetic foot. Future work will focus on the development of a control system for the quasi-passive device and clinical testing of the pneumatic ankle to demonstrate efficacy.

Retrieval of a leaflet escaped in a Tri-technologies bileaflet mechanical prosthetic valve.

PubMed

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.

Evaluation of function, performance, and preference as transfemoral amputees transition from mechanical to microprocessor control of the prosthetic knee.

PubMed

Hafner, Brian J; Willingham, Laura L; Buell, Noelle C; Allyn, Katheryn J; Smith, Douglas G

2007-02-01

To evaluate differences in function, performance, and preference between mechanical and microprocessor prosthetic knee control technologies. A-B-A-B reversal design. Home, community, and laboratory environments. Twenty-one unilateral, transfemoral amputees. Mechanical control prosthetic knee versus microprocessor control prosthetic knee (Otto Bock C-Leg). Stair rating, hill rating and time, obstacle course time, divided attention task accuracy and time, Amputee Mobility Predictor score, step activity, Prosthesis Evaluation Questionnaire score, Medical Outcomes Study 36-Item Short-Form Health Survey score, self-reported frequency of stumbles and falls, and self-reported concentration required for ambulation. Stair descent score, hill descent time, and hill sound-side step length showed significant (P<.01) improvement with the C-Leg. Users reported a significant (P<.05) decrease in frequency of stumbles and falls, frustration with falling, and difficulty in multitasking while using the microprocessor knee. Subject satisfaction with the C-Leg was significantly (P<.001) greater than the mechanical control prosthesis. The study population showed improved performance when negotiating stairs and hills, reduced frequency of stumbling and falling, and a preference for the microprocessor control C-Leg as compared with the mechanical control prosthetic knee.

75 FR 65060 - Advisory Committee on Prosthetics and Special-Disabilities Programs; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-21

...-of-the- art prosthetics and the associated rehabilitation research, development, and evaluation of... injuries, blindness or visual impairments, loss of extremities or loss of function, deafness or hearing...

Brachial plexus injury management through upper extremity amputation with immediate postoperative prostheses.

PubMed

Malone, J M; Leal, J M; Underwood, J; Childers, S J

1982-02-01

Management of patients with brachial plexus injuries requires a team approach so that all aspects of their care are addressed simultaneously. This report examines elective amputation and prosthetic rehabilitation in a patient with brachial plexus avulsion of the left arm. The best possibility for good prosthetic rehabilitation is the early application of prosthetic devices with intensive occupational therapy. Using this type of approach, we have achieved significant improvement in amputation rehabilitation of upper extremity amputees treated with immediate postoperative conventional electric and myoelectric prostheses.

Post-treatment glenoid classification system for total shoulder arthroplasty.

PubMed

Churchill, R Sean

2012-04-01

Over the past 10 years, numerous advancements in glenoid preparation and resurfacing have occurred. Current glenoid classification systems are either focused solely on the patient's preoperative glenoid bone configuration or on the available glenoid bone stock in revision arthroplasty cases. While these systems provide value in preoperative planning, they fail to properly classify the surgical reconstruction completed. A literature review of common bone preparation methods and sources of glenoid prosthetic failure was performed. Based upon this review, a classification system for grading the status of the glenoid after prosthetic implantation was developed. A 6 category, post-treatment, glenoid classification system is proposed: type 0: no reaming; type I: glenoid reaming into but not through the subchondral bone; type II: glenoid reaming which perforates through <50% of the subchondral bone surface area; type III: glenoid reaming which perforates through >50% of the subchondral bone surface area; type IV: use of structural bone graft; and type V: use of a posterior augmented glenoid prosthesis. Types I-III are further subdivided into subtype A which have 100% bone support of the prosthesis, and subtype B which have a region of unsupported prosthesis. The classification system proposed addresses the surgical management of the glenoid during prosthetic replacement. This unique approach to classifying the glenoid following surgical intervention will allow direct follow-up comparison of similarly treated glenoid replacements. Future multicenter studies, possibly through joint registry databases, could then determine the long-term efficacy of the various glenoid preparation methods. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Diamondlike carbon coating as a galvanic corrosion barrier between dental implant abutments and nickel-chromium superstructures.

PubMed

Ozkomur, Ahmet; Erbil, Mehmet; Akova, Tolga

2013-01-01

The objectives of this study were to evaluate the galvanic corrosion behavior between titanium and nickel-chromium (Ni-Cr) alloy, to investigate the effect of diamondlike carbon (DLC) coating over titanium on galvanic corrosion behavior between titanium and Ni-Cr alloy, and to evaluate the effect of DLC coating over titanium abutments on the fit and integrity of prosthetic assemblies by scanning electron microcopy (SEM). Five Ni-Cr and 10 titanium disks with a diameter of 5 mm and thickness of 3 mm were prepared. DLC coating was applied to five titanium disks. Electrode samples were prepared, and open circuit potential measurements, galvanic current measurements over platinum electrodes, and potentiodynamic polarization tests were carried out. For the SEM evaluation, 20 Ni-Cr alloy and 10 gold alloy superstructures were cast and prepared over 30 abutments. DLC coating was applied to 10 of the abutments. Following the fixation of prosthetic assemblies, the samples were embedded in acrylic resin and cross sectioned longitudinally. Internal fit evaluations were carried out through examination of the SEM images. Titanium showed more noble and electrochemically stable properties than Ni-Cr alloy. DLC coating over the cathode electrode served as an insulating film layer over the surface and prevented galvanic coupling. Results of the SEM evaluations indicated that the DLC-coated and titanium abutments showed no statistically significant difference in fit. Hence, no adverse effects on the adaptation of prosthetic components were found with the application of DLC coating over abutment surfaces. DLC coating might serve as a galvanic corrosion barrier between titanium abutments and Ni-Cr superstructures.

Surveying the interest of individuals with upper limb loss in novel prosthetic control techniques.

PubMed

Engdahl, Susannah M; Christie, Breanne P; Kelly, Brian; Davis, Alicia; Chestek, Cynthia A; Gates, Deanna H

2015-06-13

Novel techniques for the control of upper limb prostheses may allow users to operate more complex prostheses than those that are currently available. Because many of these techniques are surgically invasive, it is important to understand whether individuals with upper limb loss would accept the associated risks in order to use a prosthesis. An online survey of individuals with upper limb loss was conducted. Participants read descriptions of four prosthetic control techniques. One technique was noninvasive (myoelectric) and three were invasive (targeted muscle reinnervation, peripheral nerve interfaces, cortical interfaces). Participants rated how likely they were to try each technique if it offered each of six different functional features. They also rated their general interest in each of the six features. A two-way repeated measures analysis of variance with Greenhouse-Geisser corrections was used to examine the effect of the technique type and feature on participants' interest in each technique. Responses from 104 individuals were analyzed. Many participants were interested in trying the techniques - 83 % responded positively toward myoelectric control, 63 % toward targeted muscle reinnervation, 68 % toward peripheral nerve interfaces, and 39 % toward cortical interfaces. Common concerns about myoelectric control were weight, cost, durability, and difficulty of use, while the most common concern about the invasive techniques was surgical risk. Participants expressed greatest interest in basic prosthesis features (e.g., opening and closing the hand slowly), as opposed to advanced features like fine motor control and touch sensation. The results of these investigations may be used to inform the development of future prosthetic technologies that are appealing to individuals with upper limb loss.

Modulation of neural activity by reward in medial intraparietal cortex is sensitive to temporal sequence of reward

PubMed Central

Rajalingham, Rishi; Stacey, Richard Greg; Tsoulfas, Georgios

2014-01-01

To restore movements to paralyzed patients, neural prosthetic systems must accurately decode patients' intentions from neural signals. Despite significant advancements, current systems are unable to restore complex movements. Decoding reward-related signals from the medial intraparietal area (MIP) could enhance prosthetic performance. However, the dynamics of reward sensitivity in MIP is not known. Furthermore, reward-related modulation in premotor areas has been attributed to behavioral confounds. Here we investigated the stability of reward encoding in MIP by assessing the effect of reward history on reward sensitivity. We recorded from neurons in MIP while monkeys performed a delayed-reach task under two reward schedules. In the variable schedule, an equal number of small- and large-rewards trials were randomly interleaved. In the constant schedule, one reward size was delivered for a block of trials. The memory period firing rate of most neurons in response to identical rewards varied according to schedule. Using systems identification tools, we attributed the schedule sensitivity to the dependence of neural activity on the history of reward. We did not find schedule-dependent behavioral changes, suggesting that reward modulates neural activity in MIP. Neural discrimination between rewards was less in the variable than in the constant schedule, degrading our ability to decode reach target and reward simultaneously. The effect of schedule was mitigated by adding Haar wavelet coefficients to the decoding model. This raises the possibility of multiple encoding schemes at different timescales and reinforces the potential utility of reward information for prosthetic performance. PMID:25008408

Modulation of neural activity by reward in medial intraparietal cortex is sensitive to temporal sequence of reward.

PubMed

Rajalingham, Rishi; Stacey, Richard Greg; Tsoulfas, Georgios; Musallam, Sam

2014-10-01

To restore movements to paralyzed patients, neural prosthetic systems must accurately decode patients' intentions from neural signals. Despite significant advancements, current systems are unable to restore complex movements. Decoding reward-related signals from the medial intraparietal area (MIP) could enhance prosthetic performance. However, the dynamics of reward sensitivity in MIP is not known. Furthermore, reward-related modulation in premotor areas has been attributed to behavioral confounds. Here we investigated the stability of reward encoding in MIP by assessing the effect of reward history on reward sensitivity. We recorded from neurons in MIP while monkeys performed a delayed-reach task under two reward schedules. In the variable schedule, an equal number of small- and large-rewards trials were randomly interleaved. In the constant schedule, one reward size was delivered for a block of trials. The memory period firing rate of most neurons in response to identical rewards varied according to schedule. Using systems identification tools, we attributed the schedule sensitivity to the dependence of neural activity on the history of reward. We did not find schedule-dependent behavioral changes, suggesting that reward modulates neural activity in MIP. Neural discrimination between rewards was less in the variable than in the constant schedule, degrading our ability to decode reach target and reward simultaneously. The effect of schedule was mitigated by adding Haar wavelet coefficients to the decoding model. This raises the possibility of multiple encoding schemes at different timescales and reinforces the potential utility of reward information for prosthetic performance. Copyright © 2014 the American Physiological Society.

Neuroengineering tools/applications for bidirectional interfaces, brain-computer interfaces, and neuroprosthetic implants - a review of recent progress.

PubMed

Rothschild, Ryan Mark

2010-01-01

The main focus of this review is to provide a holistic amalgamated overview of the most recent human in vivo techniques for implementing brain-computer interfaces (BCIs), bidirectional interfaces, and neuroprosthetics. Neuroengineering is providing new methods for tackling current difficulties; however neuroprosthetics have been studied for decades. Recent progresses are permitting the design of better systems with higher accuracies, repeatability, and system robustness. Bidirectional interfaces integrate recording and the relaying of information from and to the brain for the development of BCIs. The concepts of non-invasive and invasive recording of brain activity are introduced. This includes classical and innovative techniques like electroencephalography and near-infrared spectroscopy. Then the problem of gliosis and solutions for (semi-) permanent implant biocompatibility such as innovative implant coatings, materials, and shapes are discussed. Implant power and the transmission of their data through implanted pulse generators and wireless telemetry are taken into account. How sensation can be relayed back to the brain to increase integration of the neuroengineered systems with the body by methods such as micro-stimulation and transcranial magnetic stimulation are then addressed. The neuroprosthetic section discusses some of the various types and how they operate. Visual prosthetics are discussed and the three types, dependant on implant location, are examined. Auditory prosthetics, being cochlear or cortical, are then addressed. Replacement hand and limb prosthetics are then considered. These are followed by sections concentrating on the control of wheelchairs, computers and robotics directly from brain activity as recorded by non-invasive and invasive techniques.

Neuroengineering Tools/Applications for Bidirectional Interfaces, Brain–Computer Interfaces, and Neuroprosthetic Implants – A Review of Recent Progress

PubMed Central

Rothschild, Ryan Mark

2010-01-01

The main focus of this review is to provide a holistic amalgamated overview of the most recent human in vivo techniques for implementing brain–computer interfaces (BCIs), bidirectional interfaces, and neuroprosthetics. Neuroengineering is providing new methods for tackling current difficulties; however neuroprosthetics have been studied for decades. Recent progresses are permitting the design of better systems with higher accuracies, repeatability, and system robustness. Bidirectional interfaces integrate recording and the relaying of information from and to the brain for the development of BCIs. The concepts of non-invasive and invasive recording of brain activity are introduced. This includes classical and innovative techniques like electroencephalography and near-infrared spectroscopy. Then the problem of gliosis and solutions for (semi-) permanent implant biocompatibility such as innovative implant coatings, materials, and shapes are discussed. Implant power and the transmission of their data through implanted pulse generators and wireless telemetry are taken into account. How sensation can be relayed back to the brain to increase integration of the neuroengineered systems with the body by methods such as micro-stimulation and transcranial magnetic stimulation are then addressed. The neuroprosthetic section discusses some of the various types and how they operate. Visual prosthetics are discussed and the three types, dependant on implant location, are examined. Auditory prosthetics, being cochlear or cortical, are then addressed. Replacement hand and limb prosthetics are then considered. These are followed by sections concentrating on the control of wheelchairs, computers and robotics directly from brain activity as recorded by non-invasive and invasive techniques. PMID:21060801

3D Assessment of Features Associated With Transvalvular Aortic Regurgitation After TAVR: A Real-Time 3D TEE Study.

PubMed

Shibayama, Kentaro; Mihara, Hirotsugu; Jilaihawi, Hasan; Berdejo, Javier; Harada, Kenji; Itabashi, Yuji; Siegel, Robert; Makkar, Raj R; Shiota, Takahiro

2016-02-01

This study of 3-dimensional (3D) transesophageal echocardiography (TEE) aimed to demonstrate features associated with transvalvular aortic regurgitation (AR) after transcatheter aortic valve replacement (TAVR) and to confirm the fact that a gap between the native aortic annulus and prosthesis is associated with paravalvular AR. The mechanism of AR after TAVR, particularly that of transvalvular AR, has not been evaluated adequately. All patients with severe aortic stenosis who underwent TAVR with the Sapien device (Edwards Lifesciences, Irvine, California) had 3D TEE of the pre-procedural native aortic annulus and the post-procedural prosthetic valve. In the 201 patients studied, the total AR was mild in 67 patients (33%), moderate in 21 patients (10%), and severe in no patients. There were 20 patients with transvalvular AR and 82 patients with paravalvular AR. Fourteen patients had both transvalvular and paravalvular AR. Patients with transvalvular AR had larger prosthetic expansion (p <0.05), a more elliptical prosthetic shape at the prosthetic commissure level (p <0.01) and more anti-anatomical position (p <0.001), which was defined as malposition of the prosthetic commissures in relation to the native commissures, than the patients without transvalvular AR. Age (odds ratio [OR]: 1.05; 95% confidence interval [CI]: 1.01 to 1.09; p < 0.05) and effective area oversizing (OR: 0.97; 95% CI: 0.93 to 0.99, p <0.05) were associated with mild or greater paravalvular AR. 3D TEE successfully demonstrated the features associated with transvalvular AR, such as large prosthetic expansion, elliptical prosthetic shape, and anti-anatomical position of prosthesis. Additionally, effective area oversizing was associated with paravalvular AR. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Assessment of transfemoral amputees using a passive microprocessor-controlled knee versus an active powered microprocessor-controlled knee for level walking.

PubMed

Creylman, Veerle; Knippels, Ingrid; Janssen, Paul; Biesbrouck, Evelyne; Lechler, Knut; Peeraer, Louis

2016-12-19

In transfemoral (TF) amputees, the forward propulsion of the prosthetic leg in swing has to be mainly carried out by hip muscles. With hip strength being the strongest predictor to ambulation ability, an active powered knee joint could have a positive influence, lowering hip loading and contributing to ambulation mobility. To assess this, gait of four TF amputees was measured for level walking, first while using a passive microprocessor-controlled prosthetic knee (P-MPK), subsequently while using an active powered microprocessor-controlled prosthetic knee (A-MPK). Furthermore, to assess long-term effects of the use of an A-MPK, a 4-weeks follow-up case study was performed. The kinetics and kinematics of the gait of four TF amputees were assessed while walking with subsequently the P-MPK and the A-MPK. For one amputee, a follow-up study was performed: he used the A-MPK for 4 weeks, his gait was measured weekly. The range of motion of the knee was higher on both the prosthetic and the sound leg in the A-MPK compared to the P-MPK. Maximum hip torque (HT) during early stance increased for the prosthetic leg and decreased for the sound leg with the A-MPK compared to the P-MPK. During late stance, the maximum HT decreased for the prosthetic leg. The difference between prosthetic and sound leg for HT disappeared when using the A-MPK. Also, an increase in stance phase duration was observed. The follow-up study showed an increase in confidence with the A-MPK over time. Results suggested that, partially due to an induced knee flexion during stance, HT can be diminished when walking with the A-MPK compared to the P-MPK. The single case follow-up study showed positive trends indicating that an adaptation time is beneficial for the A-MPK.

Consequences of tooth loss: 2. Dentist considerations--restorative problems and implications.

PubMed

Craddock, Helen L

2010-01-01

Partial tooth loss is much less well tolerated by patients than was previously the case and, on occasions, when extraction is inevitable, they may seek prosthetic replacement. This paper explores some of the consequences of tooth loss that may cause difficulties in tooth replacement, particularly if replacement is delayed for some time. An awareness of potential difficulties, particularly with posterior tooth replacement, will allow clinicians to make treatment decisions in the light of current evidence.

Development of upper limb prostheses: current progress and areas for growth.

PubMed

González-Fernández, Marlís

2014-06-01

Upper extremity prosthetic technology has significantly changed in recent years. The devices available and those under development are more and more able to approximate the function of the lost limb; however, other challenges remain. This article provides a brief perspective on the most advanced upper limb prostheses available and the challenges present for continued development of the technology. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Special Sessions: International Conference on Rehabilitation Engineering (2nd, Ottawa, Canada, June 17-22, 1984). Combined with RESNA 7th Annual Conference = Seances speciales: conference internationale sur la technologie de reeducation fonctionnelle (2nd, Ottawa, Canada, Juin 17-22, 1984). Tenue parallelement a la RESNA 7e conference annuelle.

ERIC Educational Resources Information Center

Rehabilitation Engineering Society of North America, Washington, DC.

These proceedings of the conference's Special Sessions contain 85 papers organized into the following sections: "Implant Materials and Devices,""Communication Aids,""Neural Prosthetics for the Disabled,""Current Concepts in Spinal Cord Rehabilitation,""New Models in…

Facilitating Children's Adjustment to Orthotic and Prosthetic Appliances.

ERIC Educational Resources Information Center

Fredrick, Jeff; Fletcher, Donna

1985-01-01

Guidelines are offered to help teachers understand the nature and use of orthotic and prosthetic appliances for disabled students. Classroom behavior observations are noted so that teachers can help monitor the child's adjustment to the appliance. (CL)

Rotationally Actuated Prosthetic Hand

NASA Technical Reports Server (NTRS)

Norton, William E.; Belcher, Jewell G., Jr.; Carden, James R.; Vest, Thomas W.

1991-01-01

Prosthetic hand attached to end of remaining part of forearm and to upper arm just above elbow. Pincerlike fingers pushed apart to degree depending on rotation of forearm. Simpler in design, simpler to operate, weighs less, and takes up less space.

Development of a Prosthesis for Urinary Control

NASA Technical Reports Server (NTRS)

Tenney, J. B.; Rabinowitz, R.; Tomkiewicz, Z.; Harrison, H. N.; Rogers, D. W.

1986-01-01

Report describes development and marketing of prosthetic sphincter for urinary control. With prosthetic device, patients void bladder every 3 to 4 hours. Periodic voiding keeps bladder muscles exercised and healthy and avoids bladder infections and kidney damage.

Estimation of the velocity and trajectory of three-dimensional reaching movements from non-invasive magnetoencephalography signals

NASA Astrophysics Data System (ADS)

Yeom, Hong Gi; Sic Kim, June; Chung, Chun Kee

2013-04-01

Objective. Studies on the non-invasive brain-machine interface that controls prosthetic devices via movement intentions are at their very early stages. Here, we aimed to estimate three-dimensional arm movements using magnetoencephalography (MEG) signals with high accuracy. Approach. Whole-head MEG signals were acquired during three-dimensional reaching movements (center-out paradigm). For movement decoding, we selected 68 MEG channels in motor-related areas, which were band-pass filtered using four subfrequency bands (0.5-8, 9-22, 25-40 and 57-97 Hz). After the filtering, the signals were resampled, and 11 data points preceding the current data point were used as features for estimating velocity. Multiple linear regressions were used to estimate movement velocities. Movement trajectories were calculated by integrating estimated velocities. We evaluated our results by calculating correlation coefficients (r) between real and estimated velocities. Main results. Movement velocities could be estimated from the low-frequency MEG signals (0.5-8 Hz) with significant and considerably high accuracy (p <0.001, mean r > 0.7). We also showed that preceding (60-140 ms) MEG signals are important to estimate current movement velocities and the intervals of brain signals of 200-300 ms are sufficient for movement estimation. Significance. These results imply that disabled people will be able to control prosthetic devices without surgery in the near future.

3D Bioprinting of Heterogeneous Aortic Valve Conduits with Alginate/Gelatin Hydrogels

PubMed Central

Duan, Bin; Hockaday, Laura A.; Kang, Kevin H.; Butcher, Jonathan T.

2013-01-01

Heart valve disease is a serious and growing public health problem for which prosthetic replacement is most commonly indicated. Current prosthetic devices are inadequate for younger adults and growing children. Tissue engineered living aortic valve conduits have potential for remodeling, regeneration, and growth, but fabricating natural anatomical complexity with cellular heterogeneity remain challenging. In the current study, we implement 3D bioprinting to fabricate living alginate/gelatin hydrogel valve conduits with anatomical architecture and direct incorporation of dual cell types in a regionally constrained manner. Encapsulated aortic root sinus smooth muscle cells (SMC) and aortic valve leaflet interstitial cells (VIC) were viable within alginate/gelatin hydrogel discs over 7 days in culture. Acellular 3D printed hydrogels exhibited reduced modulus, ultimate strength, and peak strain reducing slightly over 7-day culture, while the tensile biomechanics of cell-laden hydrogels were maintained. Aortic valve conduits were successfully bioprinted with direct encapsulation of SMC in the valve root and VIC in the leaflets. Both cell types were viable (81.4±3.4% for SMC and 83.2±4.0% for VIC) within 3D printed tissues. Encapsulated SMC expressed elevated alpha-smooth muscle actin when printed in stiff matrix, while VIC expressed elevated vimentin in soft matrix. These results demonstrate that anatomically complex, heterogeneously encapsulated aortic valve hydrogel conduits can be fabricated with 3D bioprinting. PMID:23015540

Performance of photovoltaic arrays in-vivo and characteristics of prosthetic vision in animals with retinal degeneration

PubMed Central

Lorach, Henri; Goetz, Georges; Mandel, Yossi; Lei, Xin; Kamins, Theodore I.; Mathieson, Keith; Huie, Philip; Dalal, Roopa; Harris, James S.; Palanker, Daniel

2014-01-01

Summary Loss of photoreceptors during retinal degeneration leads to blindness, but information can be reintroduced into the visual system using electrical stimulation of the remaining retinal neurons. Subretinal photovoltaic arrays convert pulsed illumination into pulsed electric current to stimulate the inner retinal neurons. Since required irradiance exceeds the natural luminance levels, an invisible near-infrared (915nm) light is used to avoid photophobic effects. We characterized the thresholds and dynamic range of cortical responses to prosthetic stimulation with arrays of various pixel sizes and with different number of photodiodes. Stimulation thresholds for devices with 140µm pixels were approximately half those of 70µm pixels, and with both pixel sizes, thresholds were lower with 2 diodes than with 3 diodes per pixel. In all cases these thresholds were more than two orders of magnitude below the ocular safety limit. At high stimulation frequencies (>20Hz), the cortical response exhibited flicker fusion. Over one order of magnitude of dynamic range could be achieved by varying either pulse duration or irradiance. However, contrast sensitivity was very limited. Cortical responses could be detected even with only a few illuminated pixels. Finally, we demonstrate that recording of the corneal electric potential in response to patterned illumination of the subretinal arrays allows monitoring the current produced by each pixel, and thereby assessing the changes in the implant performance over time. PMID:25255990

Early prosthetic aortic valve infection identified with the use of positron emission tomography in a patient with lead endocarditis.

PubMed

Amraoui, Sana; Tlili, Ghoufrane; Sohal, Manav; Bordenave, Laurence; Bordachar, Pierre

2016-12-01

18-Fluorodeoxyglucose positron emission tomography/computerized tomography (FDG PET/CT) scanning has recently been proposed as a diagnostic tool for lead endocarditis (LE). FDG PET/CT might be also useful to localize associated septic emboli in patients with LE. We report an interesting case of a LE patient with a prosthetic aortic valve in whom a trans-esophageal echocardiogram did not show associated aortic endocarditis. FDG PET/CT revealed prosthetic aortic valve infection. A second TEE performed 2 weeks after identified aortic vegetation. A longer duration of antimicrobial therapy with serial follow-up echocardiography was initiated. There was also increased uptake in the sigmoid colon, corresponding to focal polyps resected during a colonoscopy. FDG PET/CT scanning seems to be highly sensitive for prosthetic aortic valve endocarditis diagnosis. This promising diagnostic tool may be beneficial in LE patients, by identifying septic emboli and potential sites of pathogen entry.

Theoretical Study on the Mechanics of the Conjunct Gnatoprothetic Devices in the Context of Occlusive Function Rehabilitation

PubMed Central

POPESCU, M.R.; TRANĂ, F.; MANOLEA, H.; RAUTEN, ANE-MARIE; ȘURLIN, PETRA; DRAGOMIR, L.P.

2014-01-01

The partially intercalated edentation offers the practitioner the possibility of the functional rehabilitation of the dental arcades through conjunct gnato-prosthetic devices. The functions of the dento-maxilar device, disturbed by the presence of edentation, require a treatment approach so that, without pre-planning or estimating, the result can lead most of the times to failure in terms of functionality. Clinical evaluation associated with pre- and proprosthetic treatment can also impose, in some situations the evaluation of the dental units involved in prosthetic rehabilitation. The association and implementation of the prosthetic construction in the occlusive-articular ensemble, as well as the counterbalancing of the mastication forces per dental unit and whole interarch system, linked to the distribution of the forces at the level of the pillar teeth and prosthetic construction, represent the goal of this theoretical study. PMID:25729593

Theoretical study on the mechanics of the conjunct gnatoprothetic devices in the context of occlusive function rehabilitation.

PubMed

Popescu, M R; Trană, F; Manolea, H; Rauten, Ane-Marie; Șurlin, Petra; Dragomir, L P

2014-01-01

The partially intercalated edentation offers the practitioner the possibility of the functional rehabilitation of the dental arcades through conjunct gnato-prosthetic devices. The functions of the dento-maxilar device, disturbed by the presence of edentation, require a treatment approach so that, without pre-planning or estimating, the result can lead most of the times to failure in terms of functionality. Clinical evaluation associated with pre- and proprosthetic treatment can also impose, in some situations the evaluation of the dental units involved in prosthetic rehabilitation. The association and implementation of the prosthetic construction in the occlusive-articular ensemble, as well as the counterbalancing of the mastication forces per dental unit and whole interarch system, linked to the distribution of the forces at the level of the pillar teeth and prosthetic construction, represent the goal of this theoretical study.

Red flag in the emergency department: fracture and primary failure of a prosthetic valve.

PubMed

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.

Recurrent pannus formation causing prosthetic aortic valve dysfunction: Is excision without valve re-replacement applicable?

PubMed Central

2012-01-01

Prosthetic valve dysfunction at aortic position is commonly caused by pannus formation. The exact etiology is not known. It arises from ventricular aspect of the prosthesis encroaching its leaflets causing stenosis or it may remain localized causing left ventricular outflow tract obstruction without affecting valve function. The difference in location entails different approaches in management. Such a pathology requires surgical excision of the pannus with or without valve re-replacement. A recurrent pannus was observed in a female patient who needed repeated surgical intervention to excise a localized pannus without re-replacement of a well functioning prosthetic valve. Management of our case presents several questions, whether recurrence of pannus is caused by sparing the prosthetic valve, is it simply an exaggeration of an inflammatory healing process in certain individuals or is it ideal to re-replace the valve despite a well preserved function. PMID:22747790

Recurrent pannus formation causing prosthetic aortic valve dysfunction: is excision without valve re-replacement applicable?

PubMed

Darwazah, Ahmad K

2012-06-29

Prosthetic valve dysfunction at aortic position is commonly caused by pannus formation. The exact etiology is not known. It arises from ventricular aspect of the prosthesis encroaching its leaflets causing stenosis or it may remain localized causing left ventricular outflow tract obstruction without affecting valve function.The difference in location entails different approaches in management. Such a pathology requires surgical excision of the pannus with or without valve re-replacement.A recurrent pannus was observed in a female patient who needed repeated surgical intervention to excise a localized pannus without re-replacement of a well functioning prosthetic valve.Management of our case presents several questions, whether recurrence of pannus is caused by sparing the prosthetic valve, is it simply an exaggeration of an inflammatory healing process in certain individuals or is it ideal to re-replace the valve despite a well preserved function.

Ten questions on prosthetic shoulder infection

PubMed Central

Pinder, Elizabeth M; Ong, Joshua CY; Bale, R Stephen

2016-01-01

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. PMID:27583013

Ten questions on prosthetic shoulder infection.

PubMed

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.

Comparative biomechanical analysis of current microprocessor-controlled prosthetic knee joints.

PubMed

Bellmann, Malte; Schmalz, Thomas; Blumentritt, Siegmar

2010-04-01

To investigate and identify functional differences of 4 microprocessor-controlled prosthetic knee joints (C-Leg, Hybrid Knee [also called Energy Knee], Rheo Knee, Adaptive 2). Tested situations were walking on level ground, on stairs and ramps; additionally, the fall prevention potentials for each design were examined. The measuring technology used included an optoelectronic camera system combined with 2 forceplates as well as a mobile spiroergometric system. The study was conducted in a gait laboratory. Subjects with unilateral transfemoral amputations (N=9; mobility grade, 3-4; age, 22-49y) were tested. Participants were fitted and tested with 4 different microprocessor-controlled knee joints. Static prosthetic alignment, time distance parameters, kinematic and kinetic data and metabolic energy consumption. Compared with the Hybrid Knee and the Adaptive 2, the C-Leg offers clear advantages in the provision of adequate swing phase flexion resistances and terminal extension damping during level walking at various speeds, especially at higher walking speeds. The Rheo Knee provides sufficient terminal extension; however, swing phase flexion resistances seem to be too low. The values for metabolic energy consumption show only slight differences during level walking. The joint resistances generated for descending stairs and ramps relieve the contralateral side to varying degrees. When walking on stairs, safety-relevant technical differences between the investigated joint types can be observed. Designs with adequate internal resistances offer stability advantages when the foot is positioned on the step. Stumble recovery tests reveal that the different knee joint designs vary in their effectiveness in preventing the patient from falling. The patient benefits provided by the investigated electronic prosthetic knee joints differ considerably. The C-Leg appears to offer the amputee greater functional and safety-related advantages than the other tested knee joints. Reduced loading of the contralateral side has been demonstrated during ramp and stair descent. Metabolic energy consumption does not vary significantly between the tested knees. Hence, this parameter seems not to be a suitable criterion for assessing microprocessor-controlled knee components. Copyright 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Rehabilitation strategies for partially edentulous-prosthodontic principles and current trends.

PubMed

D'Souza, Dsj; Dua, Parag

2011-07-01

The prosthetic considerations for treatment of partially edentulous patients involve evaluation of important aspects such as presence of certain functional or skeletal deficits, orientation of the occlusal plane, free-way space, size and location of edentulous areas, number, strategic location and quality of the likely abutment teeth, vertical dimension, and the type of occlusion. A comprehensive evaluation, multidisciplinary approach and a sequential treatment plan, worked out in harmony with the patient's perceptions are important factors to ensure a successful outcome. This article discusses the principles, current trends and importance of clinical decisions in designing a treatment strategy when confronted with complex situations of partial edentulism.

Modular socket system versus traditionally laminated socket: a cost analysis.

PubMed

Normann, Elna; Olsson, Anna; Brodtkorb, Thor-Henrik

2011-03-01

Using the new modular socket system (MSS) to produce a prosthetic socket directly on the patient has the potential of being easier and quicker to manufacture but also incurring higher costs. The purpose of the study was to compare the costs of manufacturing a transtibial prosthetic socket using either a MSS or a standard laminated socket (PC). Concurrent controlled trial. A total of 20 patients at two orthopaedic facilities were followed with regards to the cost of manufacturing a prosthetic socket using either MSS or PC. Time aspects and material costs were considered in the cost analysis. Other factors studied include delivery time and number of visits. For the cost analysis, only direct costs pertaining to the prosthetic socket were considered. The total cost of MSS was found to be significantly higher (p < 0.01) compared to PC. However, the production and time cost was significantly lower. Delivery time to the patient was 1 day for MSS compared to 17 days for PC. Our study shows that the direct prosthetic cost of treating a patient using MSS is significantly higher than treating a patient using PC. However, the MSS prosthesis can be delivered significantly faster and with fewer visits. Further studies taking the full societal costs of MSS into account should therefore be performed. This study shows that the direct prosthetic cost of treating a patient with Modular Socket System is significantly higher than treating a patient with plastercasting with standard laminated socket. However, the Modular Socket System prosthesis can be delivered significantly faster and with fewer visits.

Analysis of colour stability of selected provisional prosthetic materials: an in vitro study.

PubMed

Koczorowski, Ryszard; Linkowska-Swidzińska, Kamila; Gedrange, Tomasz; Swidziński, Teodor

2009-08-01

Prosthetic restorative materials (that are) used for temporary fixed dentures tend to exhibit variable discolouration over several weeks of use. The aim of this study was to perform a spectrophotometric analysis of the influence of selected discolouring factors on the colour stability of provisional prosthetic materials in vitro. In the study, the following prosthetic materials for short-term use in the oral cavity were evaluated: Luxatemp, Structur 2S.C., Protemp II, Zhermacryl STC and Dentalon Plus. Samples of these materials were immersed in coffee, tea and dark fruit juice for 60 h at different pH values. Colour was evaluated by determining the monochromatic coefficients of light reflected by the samples, using a spectrophotometric method. Results received in artificial light (illuminant A) were compared with those obtained in daylight (illuminant D65). Changes in colour and its parameters according to the CIE L*a*b* system were analysed. The analysis (of the colour and colour parameters) of the tested materials in two types of light showed that Structur displayed the greatest tendency to discolouration and that the least tendency to discolouration was exhibited by Dentalon Plus. The fact that colour parameters obtained in two types of light were not identical suggests that changes in the colour of the same material may be perceived differently, depending on the illuminant. Provisional prosthetic materials show variable colour stability under different conditions in the oral cavity. The colour of prosthetic materials may be perceived differently, depending on the illuminant and the effect of the environment in which they are used.

Functional added value of microprocessor-controlled knee joints in daily life performance of Medicare Functional Classification Level-2 amputees.

PubMed

Theeven, Patrick; Hemmen, Bea; Rings, Frans; Meys, Guido; Brink, Peter; Smeets, Rob; Seelen, Henk

2011-10-01

To assess the effects of using a microprocessor-controlled prosthetic knee joint on the functional performance of activities of daily living in persons with an above-knee leg amputation. To assess the effects of using a microprocessor-controlled prosthetic knee joint on the functional performance of activities of daily living in persons with an above-knee leg amputation. Randomised cross-over trial. Forty-one persons with unilateral above-knee or knee disarticulation limb loss, classified as Medicare Functional Classification Level-2 (MFCL-2). Participants were measured in 3 conditions, i.e. using a mechanically controlled knee joint and two types of microprocessor-controlled prosthetic knee joints. Functional performance level was assessed using a test in which participants performed 17 simulated activities of daily living (Assessment of Daily Activity Performance in Transfemoral amputees test). Performance time was measured and self-perceived level of difficulty was scored on a visual analogue scale for each activity. High levels of within-group variability in functional performance obscured detection of any effects of using a microprocessor-controlled prosthetic knee joint. Data analysis after stratification of the participants into 3 subgroups, i.e. participants with a "low", "intermediate" and "high" functional mobility level, showed that the two higher functional subgroups performed significantly faster using microprocessor-controlled prosthetic knee joints. MFCL-2 amputees constitute a heterogeneous patient group with large variation in functional performance levels. A substantial part of this group seems to benefit from using a microprocessor-controlled prosthetic knee joint when performing activities of daily living.

Mechanical Properties and Simulated Aging of Silicone Maxillofacial Elastomers: Advancements in the Past 45 Years.

PubMed

Hatamleh, Muhanad M; Polyzois, Gregory L; Nuseir, Amjad; Hatamleh, Khaldoun; Alnazzawi, Ahmad

2016-07-01

To identify and discuss the findings of publications on mechanical behavior of maxillofacial prosthetic materials published since 1969. Original experimental articles reporting on mechanical properties of maxillofacial prosthetic materials were included. A two-stage search of the literature, electronic and hand search, identified relevant published studies up to May 2015. An extensive electronic search was conducted of databases including PubMed, Embase, Scopus, and Google Scholar. Included primary studies (n = 63) reported on tensile strength, tear strength, and hardness of maxillofacial prosthetic materials at baseline and after aging. The search revealed 63 papers, with more than 28 papers being published in the past 10 years, which shows an increased number of publications when compared to only 6 papers published in the 1970s. The increase is linear with significant correlation (r = 0.85). Such an increase reflects great awareness and continued developments and warrants more research in the field of maxillofacial prosthetic materials properties; however, it is difficult to directly compare results, as studies varied in maxillofacial prosthetic materials tested with various silicone elastomers being heavily investigated, standards followed in preparing test specimens, experimental testing protocols, and parameters used in setting simulated aging conditionings. It is imperative to overcome the existing variability by establishing unified national or international standards/specifications for maxillofacial prosthetic materials. Standardization organizations or bodies, the scientific community, and academia need to be coordinated to achieve this goal. In the meantime and despite all of these theoretically significant alternatives, clinical practice still faces problems with serviceability of maxillofacial prostheses. © 2016 by the American College of Prosthodontists.

[Influence of preoperative bone mass density in periprosthetic bone remodeling after implantation of ABG-II prosthesis: A 10-year follow-up].

PubMed

Aguilar Ezquerra, A; Panisello Sebastiá, J J; Mateo Agudo, J

2016-01-01

Preoperative bone mass index has shown to be an important factor in peri-prosthetic bone remodelling in short follow-up studies. Bone density scans (DXA) were used to perform a 10-year follow-up study of 39 patients with a unilateral, uncemented hip replacement. Bone mass index measurements were made at 6 months, one year, 3 years, 5 years, and 10 years after surgery. Pearson coefficient was used to quantify correlations between preoperative bone mass density (BMD) and peri-prosthetic BMD in the 7 Gruen zones at 6 months, one year, 3 years, 5 years, and 10 years. Pre-operative BMD was a good predictor of peri-prosthetic BMD one year after surgery in zones 1, 2, 4, 5 and 6 (Pearson index from 0.61 to 0.75). Three years after surgery it has good predictive power in zones 1, 4 and 5 (0.71-0.61), although in zones 3 and 7 low correlation was observed one year after surgery (0.51 and 0.57, respectively). At the end of the follow-up low correlation was observed in the 7 Gruen zones. Sex and BMI were found to not have a statistically significant influence on peri-prosthetic bone remodelling. Although preoperative BMD seems to be an important factor in peri-prosthetic remodelling one year after hip replacement, it loses its predictive power progressively, until not being a major factor in peri-prosthetic remodelling ten years after surgery. Copyright © 2015 SECOT. Published by Elsevier Espana. All rights reserved.

Attachment systems for mandibular implant overdentures: a systematic review

PubMed Central

Kim, Ha-Young; Lee, Jeong-Yol; Bryant, S. Ross

2012-01-01

PURPOSE The aim of this systematic review was to address treatment outcome according to attachment systems for mandibular implant overdentures in terms of implant survival rate, prosthetic maintenance and complications, and patient satisfaction. MATERIALS AND METHODS A systematic literature search was conducted using PubMed and hand searching of relevant journals considering inclusion and exclusion criteria. Clinical trial studies on mandibular implant overdentures until August, 2010 were selected if more than one type of overdenture attachment was reported. Twenty four studies from 1098 studies were finally included and the data on implant survival rate, prosthetic maintenance and complications, patient satisfaction were analyzed relative to attachment systems. RESULTS Four studies presented implant survival rates (95.8 - 97.5% for bar, 96.2 - 100% for ball, 91.7% for magnet) according to attachment system. Ten other studies presented an implant survival rate ranging from 93.3% to 100% without respect to the attachment groups. Common prosthetic maintenance and complications were replacement of an assay for magnet attachments, and activation of a matrix or clip for ball or bar attachments. Prosthetic maintenance and complications most commonly occurred in the magnet groups. Conflicting findings were found on the rate of prosthetic maintenance and complications comparing ball and bar attachments. Most studies showed no significant differences in patient satisfaction depending upon attachment systems. CONCLUSION The implant survival rate of mandibular overdentures seemed to be high regardless attachment systems. The prosthetic maintenance and complications may be influenced by attachment systems. However patient satisfaction may be independent of the attachment system. PMID:23236571

The Ligand Trans Influence Governs Conformation in Cobalamin-Dependent Methionine Synthase†

PubMed Central

Fleischhacker, Angela S.; Matthews, Rowena G.

2008-01-01

Cobalamin-dependent methionine synthase (MetH) of Escherichia coli is a large, modular enzyme that uses a cobalamin prosthetic group as a donor or acceptor in three separate methyl transfer reactions. The prosthetic group alternates between methylcobalamin and cob(I)alamin during catalysis as homocysteine is converted to methionine using a methyl group derived from methyltetrahydrofolate. Occasional oxidation of cob(I)alamin to cob(II)alamin inactivates the enzyme. Reductive methylation with flavodoxin and adenosylmethionine returns the enzyme to an active methylcobalamin state. At different points during the reaction cycle, the coordination of the cobalt of the cobalamin changes. The imidazole side chain of His759 coordinates to cobalamin in a “His-on” state and dissociates to produce a “His-off” state. The His-off state has been associated with a conformation of MetH that is poised for reactivation of cobalamin by reductive methylation rather than catalysis. Our studies on cob(III)alamins bound to MetH, specifically aqua-, methyl-, and n-propylcobalamin, show a correlation between the accessibility of the reactivation conformation and the order of the established ligand trans influence. The trans influence also controls the affinity of MetH in the cob(III)alamin form for flavodoxin. Flavodoxin, which acts to shift the conformational equilibrium towards the reactivation conformation, binds less tightly to MetH when the cob(III)alamin has a strong trans ligand and therefore has less positive charge on cobalt. These results are compared to those for cob(II)alamin MetH, illustrating that access to the reactivation conformation is governed by the net charge on the cobalt as well as the trans influence in cob(III)alamins. PMID:17924667

Prosthetic Hand Lifts Heavy Loads

NASA Technical Reports Server (NTRS)

Carden, James R.; Norton, William; Belcher, Jewell G.; Vest, Thomas W.

1991-01-01

Prosthetic hand designed to enable amputee to lift diverse heavy objects like rocks and logs. Has simple serrated end effector with no moving parts. Prosthesis held on forearm by system of flexible straps. Features include ruggedness, simplicity, and relatively low cost.

[Ectodermal Capdepont syndrome and oral prosthetic rehabilitation. About a clinical case].

PubMed

Kumpanya, P; Matshumba, M; Sekele, I B; Mayunga, M; Lutula, P S; Ntumba, M K

2015-03-01

The authors describe the ectodermal Capdepont syndrome as an anomaly characterized by anhidrosis, hypotrichosis and anodontia diagnosed in a 22 year-old adult. In front of this anodontia, oral prosthetic rehabilitation remains the only solution.

[Guywire dentures].

PubMed

Riakhovskiĭ, A N

2000-01-01

Analyzes possible complications and shortcomings of traditional prosthetic treatments. Presents a new approach to prosthetic treatment and describes the general design of guy dentures. Describes in brief the biomechanics, methods of making guy dentures, and discusses their advantages in comparison with the traditional dentures.

Silver Nanocoating Technology in the Prevention of Prosthetic Joint Infection

PubMed Central

Gallo, Jiri; Panacek, Ales; Prucek, Robert; Kriegova, Eva; Hradilova, Sarka; Hobza, Martin; Holinka, Martin

2016-01-01

Prosthetic joint infection (PJI) is a feared complication of total joint arthroplasty associated with increased morbidity and mortality. There is a growing body of evidence that bacterial colonization and biofilm formation are critical pathogenic events in PJI. Thus, the choice of biomaterials for implanted prostheses and their surface modifications may significantly influence the development of PJI. Currently, silver nanoparticle (AgNP) technology is receiving much interest in the field of orthopaedics for its antimicrobial properties and a strong anti-biofilm potential. The great advantage of AgNP surface modification is a minimal release of active substances into the surrounding tissue and a long period of effectiveness. As a result, a controlled release of AgNPs could ensure antibacterial protection throughout the life of the implant. Moreover, the antibacterial effect of AgNPs may be strengthened in combination with conventional antibiotics and other antimicrobial agents. Here, our main attention is devoted to general guidelines for the design of antibacterial biomaterials protected by AgNPs, its benefits, side effects and future perspectives in PJI prevention. PMID:28773461

18F-FDG-PET/CT Angiography for the Diagnosis of Infective Endocarditis.

PubMed

Roque, A; Pizzi, M N; Cuéllar-Calàbria, H; Aguadé-Bruix, S

2017-02-01

This article reviews the current imaging role of 18 F-fluordeoxyglucose positron emission computed tomography ( 18 F-FDG-PET/CT) combined with cardiac CT angiography (CTA) in infective endocarditis and discusses the strengths and limitations of this technique. The diagnosis of infective endocarditis affecting prosthetic valves and intracardiac devices is challenging because echocardiography and, therefore, the modified Duke criteria have well-recognized limitations in this clinical scenario. The high sensitivity of 18 F-FDG-PET/CT for the detection of infection associated with the accurate definition of structural damage by gated cardiac CTA in a combined technique (PET/CTA) has provided a significant increase in diagnostic sensitivity for the detection of IE. PET/CTA has proven to be a useful diagnostic tool in patients with suspected infective endocarditis. The additional information provided by this technique improves diagnostic performance in prosthetic valve endocarditis when it is used in combination with the Duke criteria. The findings obtained in PET/CTA studies have been included as a major criterion in the recently updated diagnostic algorithm in infective endocarditis guidelines.

Indications for cardiac surgery in patients with active infective endocarditis.

PubMed

Alsip, S G; Blackstone, E H; Kirklin, J W; Cobbs, C G

1985-06-28

Currently, absolute indications for valve replacement during active infective endocarditis include severe heart failure, the presence of an infecting microorganism that is not susceptible to available antimicrobial agents, and, in patients with an infected prosthetic valve, an unstable device. Relative indications include an etiologic microorganism other than a susceptible Streptococcus, relapse after presumed effective therapy, evidence of intracardiac extension of the infection, two or more systemic emboli, vegetations large enough to be demonstrated by echocardiography, and, in patients with an infected prosthetic device, early disease and periprosthetic leak. With use of data from the medical literature, a study generated by the cardiovascular surgical group at the University of Alabama School of Medicine, and a brief cost analysis, a point system was constructed to assist in decision-making concerning surgery in patients with active infective endocarditis. The usefulness of this system will depend on experience generated from its utilization in a larger number of patients as well as new data relative to a more complete understanding of the risks and benefits of surgery in this condition.

Changes in ganglion cell physiology during retinal degeneration influence excitability by prosthetic electrodes

NASA Astrophysics Data System (ADS)

Cho, Alice; Ratliff, Charles; Sampath, Alapakkam; Weiland, James

2016-04-01

Objective. Here we investigate ganglion cell physiology in healthy and degenerating retina to test its influence on threshold to electrical stimulation. Approach. Age-related Macular Degeneration and Retinitis Pigmentosa cause blindness via outer retinal degeneration. Inner retinal pathways that transmit visual information to the central brain remain intact, so direct electrical stimulation from prosthetic devices offers the possibility for visual restoration. Since inner retinal physiology changes during degeneration, we characterize physiological properties and responses to electrical stimulation in retinal ganglion cells (RGCs) of both wild type mice and the rd10 mouse model of retinal degeneration. Main results. Our aggregate results support previous observations that elevated thresholds characterize diseased retinas. However, a physiology-driven classification scheme reveals distinct sub-populations of ganglion cells with thresholds either normal or strongly elevated compared to wild-type. When these populations are combined, only a weakly elevated threshold with large variance is observed. The cells with normal threshold are more depolarized at rest and exhibit periodic oscillations. Significance. During degeneration, physiological changes in RGCs affect the threshold stimulation currents required to evoke action potentials.

Differences in Military Obstacle Course Performance Between Three Energy-Storing and Shock-Adapting Prosthetic Feet in High-Functioning Transtibial Amputees: A Double-Blind, Randomized Control Trial.

PubMed

Highsmith, M Jason; Kahle, Jason T; Miro, Rebecca M; Lura, Derek J; Carey, Stephanie L; Wernke, Matthew M; Kim, Seok Hun; Quillen, William S

2016-11-01

Approximately 683 persons engaged in military service experienced transtibial amputation (TTA) related to recent war in Iraq and Afghanistan. Military TTAs function at a level beyond basic ambulation. No empirical data demonstrate which higher functioning prosthetic feet maximize injured service personnel's ability to continue performing at a level commensurate with return to duty. This study's purpose was to determine which of three high-functioning, energy-storing prosthetic feet maximize performance and preference in a field obstacle course (OC) and to quantify physical performance differences between TTAs and high-functioning nonamputees. A randomized, double-blind, repeated measures experimental design compared three prosthetic feet (Ossur Variflex, Endolite Elite Blade, and Ossur Re-Flex Rotate) during performance on a field OC. TTAs accommodated with study feet and the OC before assessment. 14 TTAs and 14 nonamputee controls completed the course. Subjective and objective performance differences were compared across feet conditions and between groups. Total OC completion times were similar between prosthetic feet: Elite-Blade (419 seconds ± 130), Variflex (425 seconds ± 144), and Re-Flex Rotate (444 seconds ± 220). Controls' OC completion time (287.2 seconds ± 58) was less (p ≤ 0.05) than TTA times. In total, controls had faster completion times (p ≤ 0.05) compared to all prosthetic feet conditions in 13/17 obstacles. Re-Flex Rotate had 2 additional obstacles different (p ≤ 0.05) than controls and required more time to complete. Median RPE values were lower (p ≤ 0.05) for controls than TTA regardless of foot. Regarding foot preference for OC completion, 7/14 (50%) preferred Elite Blade, 5/14 (36%) preferred Re-Flex Rotate, and the remaining 2/14 (14%) preferred Variflex. Controls completed the OC faster and with less effort than TTAs regardless of prosthetic foot. No clear differences in prosthetic feet emerged during OC completion; however, individual task performance, perceived effort, and preference resulted in trends of slight performance improvement with and preference for Elite Blade, a dual function energy-storing and return foot combined with vertical shock absorption. Understanding how to maximally improve performance in such functional tasks may allow service members to best sustain physical fitness, return to their military occupational specialty and possibly in-theater duty. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

Rotational joint for prosthetic leg

NASA Technical Reports Server (NTRS)

Jones, W. C.; Owens, L. J.

1977-01-01

Device is installed in standard 30 millimeter tubing used for lower leg prosthetics. Unit allows proper rotation (about 3 degrees) of foot relative to the hip, during normal walking or running. Limited rotational movement with restoring force results in a more natural gait.

Mesofluidic controlled robotic or prosthetic finger

DOEpatents

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.

Re-operation for aortic and mitral prosthetic dysfunctions.

PubMed

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.

A rare case of prosthetic endocarditis and dehiscence in a mechanical valved conduit

PubMed Central

Kannan, Arun; Smith, Cristy; Subramanian, Sreekumar; Janardhanan, Rajesh

2014-01-01

A middle-aged adult patient with a history of aortic root replacement with a mechanical valved conduit and remote chest trauma was referred to our institution with prosthetic endocarditis. Transoesophageal echocardiogram at our institution confirmed a near-complete dehiscence of the prosthetic aortic valve from the conduit, with significant perivalvular flow forming a pseudoaneurysm. The patient underwent a high-risk re-operation, involving redo aortic root replacement with a homograft after extensive debridement of the infected tissue. The patient was discharged to an outside facility after an uncomplicated hospital course, and remains stable. PMID:24510692

A rare case of prosthetic endocarditis and dehiscence in a mechanical valved conduit.

PubMed

Kannan, Arun; Smith, Cristy; Subramanian, Sreekumar; Janardhanan, Rajesh

2014-02-07

A middle-aged adult patient with a history of aortic root replacement with a mechanical valved conduit and remote chest trauma was referred to our institution with prosthetic endocarditis. Transoesophageal echocardiogram at our institution confirmed a near-complete dehiscence of the prosthetic aortic valve from the conduit, with significant perivalvular flow forming a pseudoaneurysm. The patient underwent a high-risk re-operation, involving redo aortic root replacement with a homograft after extensive debridement of the infected tissue. The patient was discharged to an outside facility after an uncomplicated hospital course, and remains stable.

Control factors in removable complete dentures: from the articulation quintet to kinetic contact

PubMed Central

Pompa, Giorgio; Giovannetti, Agostino; Gentile, Tina; Di Carlo, Stefano

2010-01-01

Summary Hanau’s laws and the so-called articulation quintet have contributed greatly to the evolution of the prosthetic dentistry and have been further elaborated by various authors. The main aim of this study was to establish the stability of prosthetic plates by attaining balanced occlusion. Several authors have addressed the problem of removable and fixed prostheses by classifying mandibular movements into functional and parafunctional movements which extends the classical occlusal mechanics for the modern occlusal feedback model. Moreover, they suggest the use of the angle of convergence as a reference plane when manufacturing prosthetic. PMID:22238706

Differentiation between solid-ankle cushioned heel and energy storage and return prosthetic foot based on step-to-step transition cost.

PubMed

Wezenberg, Daphne; Cutti, Andrea G; Bruno, Antonino; Houdijk, Han

2014-01-01

Decreased push-off power by the prosthetic foot and inadequate roll-over shape of the foot have been shown to increase the energy dissipated during the step-to-step transition in human walking. The aim of this study was to determine whether energy storage and return (ESAR) feet are able to reduce the mechanical energy dissipated during the step-to-step transition. Fifteen males with a unilateral lower-limb amputation walked with their prescribed ESAR foot (Vari-Flex, Ossur; Reykjavik, Iceland) and with a solid-ankle cushioned heel foot (SACH) (1D10, Ottobock; Duderstadt, Germany), while ground reaction forces and kinematics were recorded. The positive mechanical work on the center of mass performed by the trailing prosthetic limb was larger (33%, p = 0.01) and the negative work performed by the leading intact limb was lower (13%, p = 0.04) when walking with the ESAR foot compared with the SACH foot. The reduced step-to-step transition cost coincided with a higher mechanical push-off power generated by the ESAR foot and an extended forward progression of the center of pressure under the prosthetic ESAR foot. Results can explain the proposed improvement in walking economy with this kind of energy storing and return prosthetic foot.

Prosthesis rejection in acquired major upper-limb amputees: a population-based survey.

PubMed

Østlie, Kristin; Lesjø, Ingrid Marie; Franklin, Rosemary Joy; Garfelt, Beate; Skjeldal, Ola Hunsbeth; Magnus, Per

2012-07-01

To estimate the rates of primary and secondary prosthesis rejection in acquired major upper-limb amputees (ULAs), to describe the most frequently reported reasons for rejection and to estimate the influence of background factors on the risk of rejection. Cross-sectional study analysing population-based questionnaire data (n = 224). Effects were analysed by logistic regression analyses and Cox regression analyses. Primary prosthesis rejection was found in 4.5% whereas 13.4% had discontinued prosthesis use. The main reasons reported for primary non-wear were a perceived lack of need and discrepancies between perceived need and the prostheses available. The main reasons reported for secondary prosthesis rejection were dissatisfaction with prosthetic comfort, function and control. Primary prosthesis rejection was more likely in ULAs amputated at high age and in ULAs with proximal amputations. Secondary prosthesis rejection was more likely in proximal ULAs and in women. Clinicians should be aware of the increased risk of rejection in proximal ULAs, elderly ULAs and in women. Emphasising individual needs will probably facilitate successful prosthetic fitting. Improved prosthesis quality and individualised prosthetic training may increase long-term prosthesis use. Further studies of the effect of prosthetic training and of the reasons for rejection of different prosthetic types are suggested.

Emergence of a Stable Cortical Map for Neuroprosthetic Control

PubMed Central

Ganguly, Karunesh; Carmena, Jose M.

2009-01-01

Cortical control of neuroprosthetic devices is known to require neuronal adaptations. It remains unclear whether a stable cortical representation for prosthetic function can be stored and recalled in a manner that mimics our natural recall of motor skills. Especially in light of the mixed evidence for a stationary neuron-behavior relationship in cortical motor areas, understanding this relationship during long-term neuroprosthetic control can elucidate principles of neural plasticity as well as improve prosthetic function. Here, we paired stable recordings from ensembles of primary motor cortex neurons in macaque monkeys with a constant decoder that transforms neural activity to prosthetic movements. Proficient control was closely linked to the emergence of a surprisingly stable pattern of ensemble activity, indicating that the motor cortex can consolidate a neural representation for prosthetic control in the presence of a constant decoder. The importance of such a cortical map was evident in that small perturbations to either the size of the neural ensemble or to the decoder could reversibly disrupt function. Moreover, once a cortical map became consolidated, a second map could be learned and stored. Thus, long-term use of a neuroprosthetic device is associated with the formation of a cortical map for prosthetic function that is stable across time, readily recalled, resistant to interference, and resembles a putative memory engram. PMID:19621062

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

PubMed

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.

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

PubMed

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 < 0.02) in those undergoing revision replacement of the hip, and the mean Hospital for Special Surgery knee score increased to 75 points (70 to 80; p < 0.01) in those undergoing revision replacement of the knee. A single-stage revision following fungal peri-prosthetic infection is feasible, with an acceptable rate of a satisfactory outcome.

The biological response to orthopedic implants for joint replacement. II: Polyethylene, ceramics, PMMA, and the foreign body reaction.

PubMed

Gibon, Emmanuel; Córdova, Luis A; Lu, Laura; Lin, Tzu-Hua; Yao, Zhenyu; Hamadouche, Moussa; Goodman, Stuart B

2017-08-01

Novel evidence-based prosthetic designs and biomaterials facilitate the performance of highly successful joint replacement (JR) procedures. To achieve this goal, constructs must be durable, biomechanically sound, and avoid adverse local tissue reactions. Different biomaterials such as metals and their alloys, polymers, ceramics, and composites are currently used for JR implants. This review focuses on (1) the biological response to the different biomaterials used for TJR and (2) the chronic inflammatory and foreign-body response induced by byproducts of these biomaterials. A homeostatic state of bone and surrounding soft tissue with current biomaterials for JR can be achieved with mechanically stable, infection free and intact (as opposed to the release of particulate or ionic byproducts) implants. Adverse local tissue reactions (an acute/chronic inflammatory reaction, periprosthetic osteolysis, loosening and subsequent mechanical failure) may evolve when the latter conditions are not met. This article (Part 2 of 2) summarizes the biological response to the non-metallic materials commonly used for joint replacement including polyethylene, ceramics, and polymethylmethacrylate (PMMA), as well as the foreign body reaction to byproducts of these materials. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1685-1691, 2017. © 2016 Wiley Periodicals, Inc.

Human-technology Integration

NASA Astrophysics Data System (ADS)

Mullen, Katharine M.

Human-technology integration is the replacement of human parts and extension of human capabilities with engineered devices and substrates. Its result is hybrid biological-artificial systems. We discuss here four categories of products furthering human-technology integration: wearable computers, pervasive computing environments, engineered tissues and organs, and prosthetics, and introduce examples of currently realized systems in each category. We then note that realization of a completely artificial sytem via the path of human-technology integration presents the prospect of empirical confirmation of an aware artificially embodied system.

Additive Manufacturing Technologies Used for Processing Polymers: Current Status and Potential Application in Prosthetic Dentistry.

PubMed

Revilla-León, Marta; Özcan, Mutlu

2018-04-22

There are 7 categories of additive manufacturing (AM) technologies, and a wide variety of materials can be used to build a CAD 3D object. The present article reviews the main AM processes for polymers for dental applications: stereolithography (SLA), digital light processing (DLP), material jetting (MJ), and material extrusion (ME). The manufacturing process, accuracy, and precision of these methods will be reviewed, as well as their prosthodontic applications. © 2018 by the American College of Prosthodontists.

Esthetic considerations for the treatment of the edentulous maxilla based on current informatic alternatives: a case report.

PubMed

Rodríguez-Tizcareño, Mario H; Barajas, Lizbeth; Pérez-Gásque, Marisol; Gómez, Salvador

2012-06-01

This report presents a protocol used to transfer the virtual treatment plan data to the surgical and prosthetic reality and its clinical application, bone site augmentation with computer-custom milled bovine bone graft blocks to their ideal architecture form, implant insertion based on image-guided stent fabrication, and the restorative manufacturing process through computed tomography-based software programs and navigation systems and the computer-aided design and manufacturing techniques for the treatment of the edentulous maxilla.