Arm Prosthesis Research Articles

Function Integration through Design for Hybrid Integrating Additive Manufacturing Technologies

AbstractAdditive manufacturing (AM) technologies enable the design of new products due to their potentials. The potential of function integration can be extended through a combination of AM with a component integrating technology forming a hybrid integrating additive manufacturing technology (hiAM). With a created development method optimization areas within a product are identified on a functional level using characteristics, structural configurations and integrated functional areas. These are derived analysing examples in literature. The method is applied to a mechanical arm and hand prosthesis.

Hybrid FPGA-CPU-Based Architecture for Object Recognition in Visual Servoing of Arm Prosthesis.

The present paper proposes an implementation of a hybrid hardware–software system for the visual servoing of prosthetic arms. We focus on the most critical vision analysis part of the system. The prosthetic system comprises a glass-worn eye tracker and a video camera, and the task is to recognize the object to grasp. The lightweight architecture for gaze-driven object recognition has to be implemented as a wearable device with low power consumption (less than 5.6 W). The algorithmic chain comprises gaze fixations estimation and filtering, generation of candidates, and recognition, with two backbone convolutional neural networks (CNN). The time-consuming parts of the system, such as SIFT (Scale Invariant Feature Transform) detector and the backbone CNN feature extractor, are implemented in FPGA, and a new reduction layer is introduced in the object-recognition CNN to reduce the computational burden. The proposed implementation is compatible with the real-time control of the prosthetic arm.

Functional performance and patient satisfaction comparison between a 3D printed and a standard transradial prosthesis: a case report

BackgroundThe delay between amputation and prosthesis fitting contributes to the high rate of prosthetic abandonment despite advances in technology. Three-dimensional (3D) printing has allowed for the rapid fabrication of prostheses. Allowing individuals with amputations to interact with a prosthesis shortly after their procedure may reduce rejection chances. The purpose of the current investigation is to compare functional outcomes and patient satisfaction between a standard transradial prosthesis fitted in a clinic with a 3D-printed prosthesis fitted remotely. The standard prosthesis featured a hook terminal device, while the 3D printed prosthesis’ terminal device was a functional hand.ResultsThe main finding of this case study was that the use of a 3D printed arm prosthesis fitted remotely resulted in better functional performance, but lower overall patient satisfaction than the standard arm prosthesis. Use of the 3D printed arm resulted in improved gross manual dexterity as measured by the Box and Block test. The 3D printed prosthesis also allowed improved performance in bimanual coordination. However, the standard-hook device scored higher in patient satisfaction survey results. The patient's concerns with the 3D printed prosthesis were the durability and effectiveness of the device.ConclusionWhile durability and complex grip patterns remain a concern, the positive attributes of 3D printed prostheses include visual appeal, ease of donning, and customization of parameters to improve upper-limb symmetry offers a promising option to familiarize new amputee patients with the use of a prosthesis. Rapid manufacturing and remote fitting allows 3D printed devices to serve as postoperative transitional devices and may function as definitive devices with minimal loss of functionality if standard clinic-based prostheses are not available.MethodsThe patient was a 59-year-old male with a traumatic transradial amputation of the dominant arm. A 3D printed transradial prosthesis was remotely fitted and manufactured using photogrammetry. Assessments were performed initially with the standard-hook prosthesis and then with the 3D printed device after a 5-week familiarization period. Functional outcomes were evaluated using the Box and Block Test and Bimanual Coordination Tray Test. Patient satisfaction was evaluated using two self-reported questionnaires (the QUEST 2.0 and the modified OPUS).

Конструкция протеза верхней конечности с увеличенным числом степеней свободы пальцев

The article deals with the design of the upper limb is arm prosthesis. In the Autodesk Inventor environment, the model is analyzed for stress-strain states, the results of which are presented in this work. It also provides a brief description and block diagram of the prosthesis control system, including the main elements and their interconnection. The resulting design is aimed at manufacturing using 3D printing technologies. The paper describes the main characteristics of the material proposed for the production of the prosthesis. The prosthesis will allow you to lift and hold objects weighing up to 5 kg, as well as perform the basic functions of a human hand based on the grips and movements described in the work, which was achieved through the use of articulated joints.

The design of an upper arm prosthesis utilising 3D printing conceived for the 2020 Tokyo paralympic games: A technical note.

This article describes the design and development of an upper-limb prosthesis for a current elite level paracyclist that was conceived for use in the 2020 Paralympic Games. The prosthetic limb was intended specifically for use in cycling time trial events. These are held on the road and in the velodrome whereby the athlete rides using a tucked aerodynamic position. The prosthesis was developed using computer aided design software and an extensive use of the 3D printed manufacturing process. The resulting technical note illustrates the design methodology and manufacturing considerations for a high performance form of assistive technology. However, it results in a solution that challenges the traditional aesthetic of prosthetic limbs intended for sport and physical activity.

Dynamical and musculoskeletal effects of arm prosthesis on sprint running for runners with unilateral transradial deficiency

Dynamical and musculoskeletal effects of arm prosthesis on sprint running for runners with unilateral transradial deficiency

Factors influencing perceived function in the upper limb prosthesis user population.

Patient-reported outcomes (PROs) can be used to evaluate perceived capacity of an individual in executing tasks in a natural environment with their prosthetic device. According to the World Health Organization International Classification of Health, Functioning, and Disability (ICF) models, there may be specific factors of a person, factors of assistive prosthetic technology, or factors related to the health condition or body function that affect their functioning and disability. However, an understanding of factors affecting an upper limb prosthesis user's perception of their ability to execute tasks in a natural environment is not well established. To use the ICF model to identify which health condition-related, body function, environmental, and personal factors influence activity as measured by perceived function in the upper limb prosthesis user population. Quantitative clinical descriptive study. Clinical offices within outpatient private practice (removed for blinding). A sample of 101 participants with upper limb amputation who use a prosthetic device and were undergoing a prosthesis fitting process. Not applicable. PROs on pain with/without a prosthesis, satisfaction, and perceived function derived from the Comprehensive Arm Prosthesis and Rehabilitation Outcomes Questionnaire. Model coefficients indicate that with a unit increase in satisfaction (p< .001) and pain (p= .031) scores (with higher pain scores signifying less pain), the mean of perceived function increases by 0.66 and 0.47 units, respectively. Conversely, for individuals with elbow disarticulation, transhumeral, shoulder disarticulation, and interscapulothoracic amputations, the mean of perceived function decreases by 22.02 units (p= .006). Based on our sample, perceived function is significantly associated with satisfaction, pain, and amputation level. These findings could potentially help to inform initial clinical approach and targeted outcomes for patients based on these factors.

Validation of the Comprehensive Arm Prosthesis and Rehabilitation Outcomes Questionnaire

Purpose: To develop and psychometrically evaluate the Comprehensive Arm Prosthesis and Rehabilitation Outcomes Questionnaire (CAPROQ), a 28-item, self-report measure of three key facets associated with successful rehabilitation (perceived function, satisfaction, and pain) designed specifically for the adult upper limb loss (ULL) population. Materials and Methods: Using a national sample of adult ULL patients (N=240), factor structure, internal consistency, convergent/concurrent validity, and known group validity of the total CAPROQ score and three subscale scores were evaluated. Results: Confirmatory factor analysis indicated adequate-to-strong factor loading on each subscale: satisfaction (.623-.913), perceived function (.572-.860) and pain (.422-.834). Internal consistencies for the total measure and measure subscales were good-to-excellent (.89-.95) and convergent validity indicated moderate-to-strong statistically significant associations between the CAPROQ subscales and relevant measures. Concurrent validity showed moderate associations between CAPROQ total score, prosthetic wear time, and psychosocial adjustment scores. Known group validity indicated significant differences on CAPROQ total score between initial and definitive fitting stages (p=.012). Conclusion: Psychometric evaluation indicated that the CAPROQ and CAPROQ subscales were structurally sound, internally consistent, and demonstrated convergent validity with currently used assessments of perceived functioning, satisfaction, and pain. CAPROQ is needed for guiding individual patient care, improving care models and future prosthesis selection and development.

Teaching patient-centred communication skills during clinical procedural skill training - a preliminary pre-post study comparing international and local medical students

BackgroundInternational medical students are frequently confronted with intercultural, psychosocial, and language barriers and often receive lower marks in written, oral, and clinical-practical examinations than fellow local students. Training communication competence in procedural skills, such as blood sampling, is further challenge in this particular group of medical students. This pre-post comparative intervention study aimed to investigate the effects of training communication skills during the performance of procedural skills (taking blood samples from a silicone model) in international and local students as part of their clinical practical medical training.MethodsStudy participants performed blood sampling on an arm prosthesis model (part-task trainer) before and after the communication skills training, focusing on accompanying communication with a simulation patient sitting next to the arm model. The pre- and post-evaluation video was assessed by two independent evaluators using a binary checklist, the Integrated Procedural Performance Instrument (IPPI) and global assessments of clinical professionalism in terms of procedural and communication performance. Linear models with mixed effects were used. Group differences regarding global competence levels were analysed with χ2-tests.ResultsInternational medical students did not perform as well as their local counterparts in the pre- and post-examinations. Both groups improved their performance significantly, whereby the international students improved more than their local counterparts in terms of their communication performance, assessed via binary checklist. Clinical professionalism evaluated via global assessments of procedural and communication performance highlights the intervention’s impact insofar as no international student was assessed as clinically not competent after the training.ConclusionsOur results suggest that already a low-dose intervention can lead to improved communication skills in medical students performing procedural tasks and significantly increase their confidence in patient interaction.

Quality of life of patients with 3D-printed arm prostheses in a rural area of Sierra Leone

IntroductionIn Sierra Leone, access to prostheses is limited due to absence of practical knowledge, materials, trained staff, and high cost. This paper investigates the impact of a 3D printed prosthesis on the health-related quality of life (HRQoL) in prosthesis recipients. MethodsPatients with upper extremity amputations were included in this case study from December 2018 until July 2019. Data on the HRQoL was gathered until April 2020 in Masanga Hospital, central rural Sierra Leone. At two follow-up moments the HRQoL was assessed by applying the standard EQ-5D-5L questionnaire. These two follow-up moments varied between one week and just over a year after receiving the prosthesis. A second patient questionnaire was used to assess prosthesis satisfaction. ResultsSeven patients were included. The results of the EQ-5D-5L questionnaire show no deterioration of the HRQoL in any patient and the overall HRQoL increased by almost 20% compared to the null measurement. One patient was lost to follow up after the first re-visit. The responses to the second questionnaire indicated that patients are satisfied with the prosthesis and use it in various situations. Patients often mentioned they feel more included in society when wearing the prosthesis. One patient says wearing the prosthesis helped in accepting the amputation. As a result, enough self-confidence was experienced without the prosthesis and the patients stopped wearing the prosthesis. DiscussionThe overall HRQoL in patients wearing a 3D-printed prosthesis increases compared to not wearing one. Assessing the HRQoL at regular intervals is important for the long-term follow-up and to safeguard sustainability and long-term success of this project. Nevertheless, defining the HRQoL is challenging due to cultural differences and misunderstandings. Therefore, the use of alternative questionnaires to define the HRQoL should be investigated. To improve and warrant long-term success, identifying long-term problems is important, and the second questionnaire accounts for this need.

Closing the Loop Between Body Compensations and Upper Limb Prosthetic Movements: A Feasibility Study

To control the robotic joints of an upper limb prosthesis, most existing approaches rely on decoding the user motor intention from electrophysiological signals produced by the subject, and then executing the desired movement. This suffers from important limitations and requires extended training, particularly when a large number of prosthetic joints have to be controlled. Even when they master the control of their prosthesis, many amputees underuse the prosthetic mobility to the benefit of compensatory body movements, whose generation is less expensive and more natural from a cognitive point of view. Indeed, with an arm prosthesis, hand movements result from a combination of human and robotic joint motions. We propose in this article to use these compensatory motions as an error signal to servo the robotic controller. This approach thus creates a coupling between body compensations and prosthetic movements. To study the feasibility of such a coupling, the concept is tested with ten able-bodied subjects wearing an emulated elbow prosthesis and one congenital arm amputee. The results validate the concept, which allows naive subjects to control the prosthetic joint with no or very short training period.

Robotic Smart Prosthesis Arm with BCI and Kansei / Kawaii / Affective Engineering Approach. Pt I: Quantum Soft Computing Supremacy

A description of the design stage and results of the development of the conceptual structure of a robotic prosthesis arm is given. As a result, a prototype of manmade prosthesis on a 3D printer as well as a foundation for computational intelligence presented. The application of soft computing technology (the first step of IT) allows to extract knowledge directly from the physical signal of the electroencephalogram, as well as to form knowledge-based intelligent robust control of the lower performing level taking into account the assessment of the patient’s emotional state. The possibilities of applying quantum soft computing technologies (the second step of IT) in the processes of robust filtering of electroencephalogram signals for the formation of mental commands and quantum supremacy simulation of robotic prosthetic arm discussed.

Biological Plausibility of Arm Postures Influences the Controllability of Robotic Arm Teleoperation.

ObjectiveWe investigated how participants controlling a humanoid robotic arm’s 3D endpoint position by moving their own hand are influenced by the robot’s postures. We hypothesized that control would be facilitated (impeded) by biologically plausible (implausible) postures of the robot.BackgroundKinematic redundancy, whereby different arm postures achieve the same goal, is such that a robotic arm or prosthesis could theoretically be controlled with less signals than constitutive joints. However, congruency between a robot’s motion and our own is known to interfere with movement production. Hence, we expect the human-likeness of a robotic arm’s postures during endpoint teleoperation to influence controllability.MethodTwenty-two able-bodied participants performed a target-reaching task with a robotic arm whose endpoint’s 3D position was controlled by moving their own hand. They completed a two-condition experiment corresponding to the robot displaying either biologically plausible or implausible postures.ResultsUpon initial practice in the experiment’s first part, endpoint trajectories were faster and shorter when the robot displayed human-like postures. However, these effects did not persist in the second part, where performance with implausible postures appeared to have benefited from initial practice with plausible ones.ConclusionHumanoid robotic arm endpoint control is impaired by biologically implausible joint coordinations during initial familiarization but not afterwards, suggesting that the human-likeness of a robot’s postures is more critical for control in this initial period.ApplicationThese findings provide insight for the design of robotic arm teleoperation and prosthesis control schemes, in order to favor better familiarization and control from their users.

Intent Prediction Based on Biomechanical Coordination of EMG and Vision-Filtered Gaze for End-Point Control of an Arm Prosthesis.

We propose a novel controller for powered prosthetic arms, where fused EMG and gaze data predict the desired end-point for a full arm prosthesis, which could drive the forward motion of individual joints. We recorded EMG, gaze, and motion-tracking during pick-and-place trials with 7 able-bodied subjects. Subjects positioned an object above a random target on a virtual interface, each completing around 600 trials. On average across all trials and subjects gaze preceded EMG and followed a repeatable pattern that allowed for prediction. A computer vision algorithm was used to extract the initial and target fixations and estimate the target position in 2D space. Two SVRs were trained with EMG data to predict the x- and y- position of the hand; results showed that the y-estimate was significantly better than the x-estimate. The EMG and gaze predictions were fused using a Kalman Filter-based approach, and the positional error from using EMG-only was significantly higher than the fusion of EMG and gaze. The final target position Root Mean Squared Error (RMSE) decreased from 9.28 cm with an EMG-only prediction to 6.94 cm when using a gaze-EMG fusion. This error also increased significantly when removing some or all arm muscle signals. However, using fused EMG and gaze, there were no significant difference between predictors that included all muscles, or only a subset of muscles.

Comparison of DEKA Arm and Body-Powered Upper Limb Prosthesis Joint Kinematics

ObjectivesTo study the effects of advancements in upper-limb prosthesis technology on the user through biomechanical analyses at the joint level to quantitatively examine movement differences of individuals using an advanced upper-limb device, the DEKA Arm, and a conventional device, a body-powered Hosmer hook. DesignClinical measurement. SettingLaboratories at the United States Food and Drug Administration. ParticipantsConvenience sample of participants (N=14) with no upper limb disability or impairment. InterventionsAll participants were trained on either an upper limb body-powered (n=6) or DEKA Arm (n=8) bypass device. Main Outcome MeasuresParticipants completed the Jebsen-Taylor Hand Function Test (JHFT) and targeted Box and Blocks Test within a motion capture framework. Task completion times and joint angle trajectories for each degree of freedom of the right elbow, right shoulder, and torso were collected and analyzed for range of motion, mean angle, maximum angle, and angle path length during each task. ResultsSignificant differences between devices were observed across metrics in at least one task for each degree of freedom. Completion times were significantly higher for DEKA users (eg, 30.51±19.29s vs 9.30±1.44s) for JHFT–simulated feeding. Some kinematic measures, such as angle path length, were significantly lower in DEKA users, with the greatest difference in the right elbow flexion path length during JHFT–Page Turning (0.29±0.14 units vs 0.11±0.04 units). ConclusionsResults from this work elucidate the effect of the device on the user’s movement approach and performance, as well as emphasizing the importance of capturing movement quality into the assessment of function for advanced prosthetic technology to fully understand and evaluate potential benefits.

Improving Lives in Three Dimensions: The Feasibility of 3D Printing for Creating Personalized Medical Aids in a Rural Area of Sierra Leone.

The aim of this feasibility study was to investigate how a 3D printer could be put to its best use in a resource-limited healthcare setting. We have examined whether a 3D printer can contribute to making prostheses, braces, or splints for patients who underwent major limb amputation because of complex wounds, for example, due to burns and subsequent scarring, accidents, conflicts, or congenital abnormalities. During a 3-month period, we investigated the benefits of customized, 3D-printed arm prostheses, splints, and braces in Sierra Leone. Using a handheld 3D scanner and a 3D printer, patient-specific medical aids were designed, manufactured, and tested. Questionnaires regarding patient satisfaction and the functionality of the prostheses were used for a short-term follow-up. Four esthetic prostheses were designed: two prostheses of the hand, one of the forearm, and one of the entire arm. Follow-ups were conducted after 3 to 4 weeks to investigate the quality of the prostheses and to complete a patient questionnaire. Even though the prostheses primarily fulfill esthetic needs, they also exhibit some degree of functionality. In addition, four splints for hands and arms were made to prevent scar contractures after skin transplantation. Finally, a brace for a young boy with kyphoscoliosis was manufactured. The boy has accepted the brace and will be followed up in the months to come. Long-term follow-up is required to prove the sustainability of the 3D-printed brace and prosthetic arms. Further research into how to sustain and refine this project is underway.

Cognitive intelligent control of a robotic prosthesis arm. Part 2

Cognitive intelligent control of a robotic prosthesis arm. Part 2

Proposta para confecção de implantes protéticos de braços mecânicos com custos reduzidos.

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Advances in Orthotic and Prosthetic Manufacturing: A Technology Review.

In this work, the recent advances for rapid prototyping in the orthoprosthetic industry are presented. Specifically, the manufacturing process of orthoprosthetic aids are analysed, as thier use is widely extended in orthopedic surgery. These devices are devoted to either correct posture or movement (orthosis) or to substitute a body segment (prosthesis) while maintaining functionality. The manufacturing process is traditionally mainly hand-crafted: The subject’s morphology is taken by means of plaster molds, and the manufacture is performed individually, by adjusting the prototype over the subject. This industry has incorporated computer aided design (CAD), computed aided engineering (CAE) and computed aided manufacturing (CAM) tools; however, the true revolution is the result of the application of rapid prototyping technologies (RPT). Techniques such as fused deposition modelling (FDM), selective laser sintering (SLS), laminated object manufacturing (LOM), and 3D printing (3DP) are some examples of the available methodologies in the manufacturing industry that, step by step, are being included in the rehabilitation engineering market—an engineering field with growth and prospects in the coming years. In this work we analyse different methodologies for additive manufacturing along with the principal methods for collecting 3D body shapes and their application in the manufacturing of functional devices for rehabilitation purposes such as splints, ankle-foot orthoses, or arm prostheses.

Flexible Approach for Classifying EMG Signals for Rehabilitation Applications

Generally, the system used for recording and analysis of surface electromyography (sEMG) signals consists of an acquisition card (data), a preamplifier, and a software code for signal acquisition and signal conditioning at different stages (e.g., utilization of wavelet transform) before feeding to statistical evaluation. In our study, basically, two independent muscle locations (m.m. biceps and triceps of the human upper limb) were selected for the recording of data with multiple motion activities; analysis of the recorded data was carried out based on the extracted parameters. Further, a computational tool of analysis of variance (ANOVA) algorithm and wavelet decomposition db2 were implemented and consequently used for identifying the best mechanism for dual-channel muscle positions in the course of independent arm movements. The respective procedures are described; the results obtained are analyzed from the aspect of the possibility of their use for the control of a robot arm and upper limb prostheses.