The roles of predisposing characteristics, established need, and enabling resources on upper extremity prosthesis use and abandonment

Prosthesis usability experience is associated with extent of upper limb prosthesis adoption: A Structural Equation Modeling (SEM) analysis

Factors associated with upper limb prosthesis adoption are not well understood. In this study, we explored how prosthesis usability experience relates to the extent of prosthesis adoption through the development of a structural equation model (SEM). First, items related to prosthesis usability were developed and refined using cognitive testing and pilot testing and employed in a survey of 402 prosthesis users (mean age 61.7 (sd 14.4), 77.1% Veterans). The SEM examined two unidimensional latent constructs: Prosthesis Usability Experience and Prosthesis Adoption-and each had multiple measured indicators. SEMs tested direct as well as moderating and mediating effects between the latent constructs and covariates related to demographics and prosthesis type. SEM found a significant positive association between Prosthesis Usability Experience and Extent of Prosthesis Adoption. Several covariates had direct effects on prosthesis adoption: 1) Extent of Prosthesis Adoption was lower for those with transhumeral and shoulder amputation, and higher for those with bilateral amputation, compared to the reference group with unilateral transradial amputation and 2) Myoelectric multiple degree of freedom (multi-DOF) prosthesis use was associated with lower Extent of Prosthesis Adoption, compared to body-powered prosthesis use. Myoelectric multi-DOF use also modified the effect of Prosthesis Usability Experience on Extent of Prosthesis Adoption. For those with bilateral ULA, the strength of the relationship between Prosthesis Usability Experience and Extent of Prosthesis Adoption was reduced. Findings suggest that in order to increase prosthesis adoption, prosthetics developers and rehabilitation providers should focus on implementing strategies to improve prosthesis usability experience. New Prosthesis Usability Experience measures could be used to identify persons at greater risk for poor prosthesis adoption and target interventions to increase prosthesis use.

Sex and gender differences in upper extremity prosthesis rejection: A review of literature

Prosthesis rejection is a significant barrier to rehabilitation of persons with upper limb difference. Many individual factors can affect device rejection, including a person's sex or gender. The objective of this narrative review was to explore the reported differences between the sexes and genders in upper limb prosthesis rejection. This review considered peer-reviewed, published research studies in which the study population were adults (aged 18 and older) who had unilateral or bilateral limb difference (any level) of any etiology with current, past, or no history of prosthetic device usage. Using identified keywords, index terms, and a peer-reviewed search filter, the literature was searched in MEDLINE, Embase, and PsycInfo. The reasons for rejection, disuse, or abandonment of prosthetic devices were extracted, with the focus on reported differences between sex and genders. After searching, 29 articles were selected for full-text review and 15 were included. Only 5 of 15 articles examined differences between the sexes. Women tend to reject upper extremity prostheses more than men both before and after being fit with a device; device characteristics, such as weight and cosmesis, do not appear to be appropriately designed for women; and there may not be adequate consideration of the goals for women with limb difference(s). There is inadequate reporting of sex and gender in the literature on prosthesis rejection; future studies should report and explore these factors to determine whether the needs of the full population with limb loss are being met.

Current status and clinical perspectives of extended reality for myoelectric prostheses: review

Training with "Extended Reality" or X-Reality (XR) systems can undoubtedly enhance the control of the myoelectric prostheses. However, there is no consensus on which factors improve the efficiency of skill transfer from virtual training to actual prosthesis abilities. This review examines the current status and clinical applications of XR in the field of myoelectric prosthesis training and analyses possible influences on skill migration. We have conducted a thorough search on databases in the field of prostheses using keywords such as extended reality, virtual reality and serious gaming. Our scoping review encompassed relevant applications, control methods, performance evaluation and assessment metrics. Our findings indicate that the implementation of XR technology for myoelectric rehabilitative training on prostheses provides considerable benefits. Additionally, there are numerous standardised methods available for evaluating training effectiveness. Recently, there has been a surge in the number of XR-based training tools for myoelectric prostheses, with an emphasis on user engagement and virtual training evaluation. Insufficient attention has been paid to significant limitations in the behaviour, functionality, and usage patterns of XR and myoelectric prostheses, potentially obstructing the transfer of skills and prospects for clinical application. Improvements are recommended in four critical areas: activities of daily living, training strategies, feedback, and the alignment of the virtual environment with the physical devices.

Prosthesis nonuse and discontinuation in United States veterans with major limb amputation: Results of a national survey

BACKGROUND

Prosthesis use in persons with amputation can improve mobility and functional independence. Better understanding of the reasons for and outcomes associated with prosthesis nonuse is important to optimize function and long-term health in persons with amputation.

OBJECTIVES

Study objectives were to describe the rate, reasons for, and factors associated with never using or discontinuing prosthesis use in United States (US) veterans with amputation.

STUDY DESIGN

Cross-sectional study design.

METHODS

The study used an online survey to assess prosthesis use and satisfaction in veterans with upper-limb and lower-limb amputation. Survey participation invitations were distributed by email, text message, and mail to 46,613 potential participants.

RESULTS

The survey response rate was 11.4%. After exclusions, an analytic sample of 3,959 respondents with a major limb amputation was identified. The sample was 96.4% male; 78.3% White, with mean age of 66.9; and mean of 18.2 years since amputation. The rate of never using a prosthesis was 8.2%, and the rate of prosthesis discontinuation was 10.5%. Functionality (62.0%), undesirable prosthesis characteristics (56.9%), and comfort (53.4%) were the most common reasons for discontinuation. After controlling for the amputation subgroup, the odds of prosthesis discontinuation were higher for those with unilateral upper-limb amputation, female gender, White race (compared with Black race), diabetes, above-knee amputation, and lower prosthesis satisfaction. Prosthesis satisfaction and quality of life were highest for current prosthesis users.

CONCLUSIONS

This study adds new understanding regarding the rate and reasons for prosthesis nonuse in veterans and highlights the important relationship between prosthesis discontinuation and prosthesis satisfaction, quality of life, and satisfaction with life.

An Exploratory Multi-Session Study of Learning High-Dimensional Body-Machine Interfacing for Assistive Robot Control

Individuals who suffer from severe paralysis often lose the capacity to perform fundamental body movements and everyday activities. Empowering these individuals with the ability to operate robotic arms, in high degrees-of-freedom (DoFs), can help to maximize both functional utility and independence. However, robot teleoperation in high DoFs currently lacks accessibility due to the challenge in capturing high-dimensional control signals from the human, especially in the face of motor impairments. Body-machine interfacing is a viable option that offers the necessary high-dimensional motion capture, and it moreover is noninvasive, affordable, and promotes movement and motor recovery. Nevertheless, to what extent body-machine interfacing is able to scale to high-DoF robot control, and whether it is feasible for humans to learn, remains an open question. In this exploratory multi-session study, we demonstrate the feasibility of human learning to operate a body-machine interface to control a complex, assistive robotic arm. We use a sensor net of four inertial measurement unit sensors, bilaterally placed on the scapulae and humeri. Ten uninjured participants are familiarized, trained, and evaluated in reaching and Activities of Daily Living tasks, using the body- machine interface. Our results suggest the manner of control space mapping (joint-space control versus task-space control), from interface to robot, plays a critical role in the evolution of human learning. Though joint-space control shows to be more intuitive initially, task-space control is found to have a greater capacity for longer-term improvement and learning.

Reimagining Prosthetic Control: A Novel Body-Powered Prosthetic System for Simultaneous Control and Actuation

Globally, the most popular upper-limb prostheses are powered by the human body. For body-powered (BP) upper-limb prostheses, control is provided by changing the tension of (Bowden) cables to open or close the terminal device. This technology has been around for centuries, and very few BP alternatives have been presented since. This paper introduces a new BP paradigm that can overcome certain limitations of the current cabled systems, such as a restricted operation space and user discomfort caused by the harness to which the cables are attached. A new breathing-powered system is introduced to give the user full control of the hand motion anywhere in space. Users can regulate their breathing, and this controllable airflow is then used to power a small Tesla turbine that can accurately control the prosthetic finger movements. The breathing-powered device provides a novel prosthetic option that can be used without limiting any of the user’s body movements. Here we prove that it is feasible to produce a functional breathing-powered prosthetic hand and show the models behind it along with a preliminary demonstration. This work creates a step-change in the potential BP options available to patients in the future.

Hierarchical Human-Inspired Control Strategies for Prosthetic Hands

The abilities of the human hand have always fascinated people, and many studies have been devoted to describing and understanding a mechanism so perfect and important for human activities. Hand loss can significantly affect the level of autonomy and the capability of performing the activities of daily life. Although the technological improvements have led to the development of mechanically advanced commercial prostheses, the control strategies are rather simple (proportional or on/off control). The use of these commercial systems is unnatural and not intuitive, and therefore frequently abandoned by amputees. The components of an active prosthetic hand are the mechatronic device, the decoding system of human biological signals into gestures and the control law that translates all the inputs into desired movements. The real challenge is the development of a control law replacing human hand functions. This paper presents a literature review of the control strategies of prosthetics hands with a multiple-layer or hierarchical structure, and points out the main critical aspects of the current solutions, in terms of human's functions replicated with the prosthetic device. The paper finally provides several suggestions for designing a control strategy able to mimic the functions of the human hand.

5-Year Activity and Participation Outcomes of the First Successful Pediatric Bilateral Hand Transplantation: A Case Report

AIMS

Describe the 5-year outcomes of the first successful pediatric bilateral hand transplantation.

METHODS

The child underwent quadrimembral amputation at age two and received bilateral hand allografts at age eight. Rehabilitation included biomechanical, neurorehabilitation, and occupational approaches in acute and outpatient settings. Therapist observed outcomes, patient-reported measures, and parent-reported measures were repeated over a 5-year period.

RESULTS

Observation assessments revealed functional dexterity skills and modified independence to full independence with self-care activities. The parent reported the child had moderate difficulty with upper extremity functioning 25-, 41-, and 48-months post-transplantation, and mild difficulty at 60-months; the child reported no difficulties in this domain at 41 months. Five years post-transplantation the child reported enjoying many age-appropriate activities, and high-quality peer relations were endorsed by both parent and child.

CONCLUSION

The child developed hand movements for daily activities and was completing daily activities with improved efficiency. Health-related quality of life outcomes were favorable.

Usability Assessment of Body Controlled Electric Hand Prostheses: A Pilot Study

Poly-articulated hands, actuated by multiple motors and controlled by surface myoelectric technologies, represent the most advanced aids among commercial prostheses. However, simple hook-like body-powered solutions are still preferred for their robustness and control reliability, especially for challenging environments (such as those encountered in manual work or developing countries). This study presents the mechatronic implementation and the usability assessment of the SoftHand Pro-Hybrid, a family of poly-articulated, electrically-actuated, and body-controlled artificial hands, which combines the main advantages of both body-powered and myoelectric systems in a single device. An assessment of the proposed system is performed with individuals with and without limb loss, using as a benchmark the SoftHand Pro, which shares the same soft mechanical architecture, but is controlled using surface electromyographic sensors. Results indicate comparable task performance between the two control methods and suggest the potential of the SoftHand Pro-Hybrid configurations as a viable alternative to myoelectric control, especially in work and demanding environments.

Early life experience sets hard limits on motor learning as evidenced from artificial arm use

The study of artificial arms provides a unique opportunity to address long-standing questions on sensorimotor plasticity and development. Learning to use an artificial arm arguably depends on fundamental building blocks of body representation and would therefore be impacted by early life experience. We tested artificial arm motor-control in two adult populations with upper-limb deficiencies: a congenital group—individuals who were born with a partial arm, and an acquired group—who lost their arm following amputation in adulthood. Brain plasticity research teaches us that the earlier we train to acquire new skills (or use a new technology) the better we benefit from this practice as adults. Instead, we found that although the congenital group started using an artificial arm as toddlers, they produced increased error noise and directional errors when reaching to visual targets, relative to the acquired group who performed similarly to controls. However, the earlier an individual with a congenital limb difference was fitted with an artificial arm, the better their motor control was. Since we found no group differences when reaching without visual feedback, we suggest that the ability to perform efficient visual-based corrective movements is highly dependent on either biological or artificial arm experience at a very young age. Subsequently, opportunities for sensorimotor plasticity become more limited.

Training for users of myoelectric multigrip hand prostheses: a scoping review

BACKGROUND

Training is crucial to develop the ability to operate a myoelectric prosthetic hand and use it in daily life. Multigrip prostheses, with their wider repertoire of functions, require further training. Because studies show that prosthesis abandonment is an issue and the advanced functions are not used to the expected extent, the question of what training should be offered to patients arises. If the available training methods were synthesized, the training could be improved to the benefit of the people who are fitted with a multigrip prosthesis.

OBJECTIVE

To critically examine the content of published sources for training of users with myoelectric multigrip hand prostheses.

STUDY DESIGN

Scoping review.

METHODS

A literature search covering the period 2007-2020 in the databases PubMed, CINAHL, and Allied and Complementary Medicine Database, as well as gray literature from prosthesis manufacturers, identified 2,005 sources. After full-text review of 88 articles and four user manuals from manufacturers, nine sources were included and analyzed in their entirety.

RESULTS

We found few descriptions of multigrip prosthesis training, and no source described all training phases in detail. Integration of the prosthesis and training in daily activities was described least. Few sources actually described how to perform training in multigrip functions, and none described how to integrate these functions in daily life.

CONCLUSIONS

Existing training instructions for using multigrip prosthetic hands are inadequate, providing poor guidance to clinicians and insufficient training for patients. Further research is needed into the efficiency of various training methods.

Longitudinal study of prosthesis use in veterans with upper limb amputation

BACKGROUND

Little is known about the patterns of prosthesis use and satisfaction of those who cease use or begin to use upper limb prostheses.

OBJECTIVES

Among a longitudinal sample of Veterans with upper limb amputation, (1) describe changes in prosthesis use over 1 year, (2) examine rates of receipt of new prostheses, and (3) compare prosthesis satisfaction in respondents who received a new prosthesis to those who did not.

STUDY DESIGN

Longitudinal survey.

METHODS

808 Veterans who had participated in a baseline interview 1 year earlier were invited to participate in structured telephone interviews.

RESULTS

A total of 562 persons with unilateral and 23 with bilateral amputation participated in the interviews (Response rate = 72.4% and 85.2%, respectively). Prosthesis use, frequency and intensity of use, and types of prostheses used were stable over 1 year. About 24% reported using a different primary terminal device type at follow-up than baseline. Prosthesis use was less frequent/intense at baseline among those who discontinued use compared with those who did not (P < 0.05), and less frequent/intense for those who started compared with those who continued using a prosthesis (P < 0.0001). Rates of prosthetic training were higher among those who received a different prosthesis type compared with those using the same type (P = 0.06). Satisfaction scores were higher (P < 0.01) for new prosthesis recipients, and lower at baseline for prosthesis abandoners compared with continued users (P = 0.03).

CONCLUSION

Prosthesis abandonment appears to be predicated on dissatisfaction with the device, as well as less frequent/intense prosthesis use. These findings can be used to identify those at risk for prosthesis abandonment and improve their prosthesis experience.

A Multimodal Intention Detection Sensor Suite for Shared Autonomy of Upper-Limb Robotic Prostheses

Neurorobotic augmentation (e.g., robotic assist) is now in regular use to support individuals suffering from impaired motor functions. A major unresolved challenge, however, is the excessive cognitive load necessary for the human–machine interface (HMI). Grasp control remains one of the most challenging HMI tasks, demanding simultaneous, agile, and precise control of multiple degrees-of-freedom (DoFs) while following a specific timing pattern in the joint and human–robot task spaces. Most commercially available systems use either an indirect mode-switching configuration or a limited sequential control strategy, limiting activation to one DoF at a time. To address this challenge, we introduce a shared autonomy framework centred around a low-cost multi-modal sensor suite fusing: (a) mechanomyography (MMG) to estimate the intended muscle activation, (b) camera-based visual information for integrated autonomous object recognition, and (c) inertial measurement to enhance intention prediction based on the grasping trajectory. The complete system predicts user intent for grasp based on measured dynamical features during natural motions. A total of 84 motion features were extracted from the sensor suite, and tests were conducted on 10 able-bodied and 1 amputee participants for grasping common household objects with a robotic hand. Real-time grasp classification accuracy using visual and motion features obtained 100%, 82.5%, and 88.9% across all participants for detecting and executing grasping actions for a bottle, lid, and box, respectively. The proposed multimodal sensor suite is a novel approach for predicting different grasp strategies and automating task performance using a commercial upper-limb prosthetic device. The system also shows potential to improve the usability of modern neurorobotic systems due to the intuitive control design.

User-relevant factors determining prosthesis choice in persons with major unilateral upper limb defects: A meta-synthesis of qualitative literature and focus group results

OBJECTIVE

Considering the high rejection rates of upper limb prostheses, it is important to determine which prosthesis fits best the needs of each user. The introduction of the multi-grip prostheses hands (MHP), which have functional advantages but are also more expensive, has made prosthesis selection even harder. Therefore, we aimed to identify user opinions on factors determining prosthesis choice of persons with major unilateral upper limb defects in order to facilitate a more optimal fit between user and prosthesis.

METHODS

A qualitative meta-synthesis using a 'best-fit framework' approach was performed by searching five databases (PROSPERO registration number: CRD42019126973). Studies were considered eligible if they contained qualitative content about adults with major unilateral upper limb defects experienced in using commercially available upper limb prostheses and focused on upper limb prosthesis users' opinions. Results of the meta-synthesis were validated with end-users (n = 11) in a focus group.

RESULTS

Out of 6247 articles, 19 studies were included. An overview of six main themes ('physical', 'activities and participation', 'mental', 'social', 'rehabilitation, cost and prosthetist services' and 'prosthesis related factors') containing 86 subthemes that could affect prosthesis choice was created. Of these subthemes, 19 were added by the focus group. Important subthemes were 'work/school', 'functionality' and 'reactions from public'. Opinions of MHP-users were scarce. MHPs were experienced as more dexterous and life-like but also as less robust and difficult to control.

CONCLUSION

The huge number of factors that could determine upper limb prosthesis choice explains that preferences vary greatly. The created overview can be of great value to identify preferences and facilitate user-involvement in the selection process. Ultimately, this may contribute to a more successful match between user and prosthesis, resulting in a decrease of abandonment and increase of cost-effectiveness.

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

Objectives

To 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.

Design

Clinical measurement.

Setting

Laboratories at the United States Food and Drug Administration.

Participants

Convenience sample of participants (N=14) with no upper limb disability or impairment.

Interventions

All participants were trained on either an upper limb body-powered (n=6) or DEKA Arm (n=8) bypass device.

Main Outcome Measures

Participants 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.

Results

Significant 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).

Conclusions

Results 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.

A National Survey of Prosthesis Use in Veterans with Major Upper Limb Amputation: Comparisons by Gender

BACKGROUND

A better understanding of women veterans with upper limb amputation is needed.

OBJECTIVE

To compare prosthetic use and outcomes of female and male veterans with upper limb amputation.

DESIGN

Cross-sectional survey: Amputation characteristics, prosthesis use, and quality of life outcomes were compared by gender. Separate logistic regression models examined association of gender with prosthesis use and receipt of training to use a prosthesis. Separate linear regression models examined the relationship between gender and health-related quality of life (HRQoL) outcomes.

PARTICIPANTS

Participants were veterans with major upper limb amputation who received care at the Department of Veterans Affairs (VA) in 2010-2015, identified from VA data sources. A total of 808 individuals (755 men, 21 women) were surveyed by telephone.

MAIN OUTCOME MEASURES

Disabilities of the Arm, Shoulder and Hand (QuickDASH), VR-12 Physical Component Summary (PCS) and VR-12 Mental Component Summary (MCS), Trinity Amputation and Prosthetic Experience Scale satisfaction scale, Orthotics and Prosthetic User's Survey client satisfaction with devices scale.

SETTING

Telephone survey of community dwelling participants.

INTERVENTIONS

Not applicable.

RESULTS

Survey response rate was 47.3% for men and 62.8% for women. Women were less likely to have ever used a prosthesis (adjusted odds ratio [aOR] = 0.26; confidence interval [CI] 0.08-0.88), have received training for an initial prosthesis (aOR: 0.24; CI 0.08-0.70), be current users (aOR = 0.34; CI 0.12-1.01), and have received training for a current prosthesis (aOR: 0.15; 0.03-0.87). A greater proportion of women used cosmetic and a smaller proportion used body-powered devices compared to men (P < .05). Device heaviness or fatigue was the most common reason for abandonment. There were no significant differences in outcome measures by gender.

CONCLUSIONS

Women were less likely than men to have ever used and currently use prostheses or to have received prosthetic training, more likely to use cosmetic devices, and less likely to use body-powered devices. Efforts to develop prostheses that are cosmetically acceptable, yet lightweight and functional, are needed.

Prosthesis satisfaction in a national sample of Veterans with upper limb amputation

BACKGROUND

Many persons with upper limb amputation reject prostheses, and many are not satisfied with their devices. Research is needed to understand modifiable factors related to device satisfaction. Myoelectric devices with multiple degrees of freedom are now available; however, no studies have examined whether they lead to greater device satisfaction. Prosthetic training contributes to more skillful prosthesis use and greater likelihood of long-term use; however, the relationship between training and device satisfaction is unclear.

OBJECTIVES

(1) To describe and compare satisfaction by prosthesis and terminal device type and (2) to identify factors associated with satisfaction.

STUDY DESIGN

Cross-sectional study.

METHODS

Participants were 449 persons with unilateral upper limb amputation who used a prosthesis. Participants described their prostheses, prosthetic training, device repairs, visits to a prosthetist, and rated device satisfaction using two standardized measures (Trinity Amputation and Prosthesis Experience Scales Satisfaction scale and Orthotics and Prosthetics Users' Survey - Client Satisfaction with Devices scale). Multivariate generalized linear regression models examined the relationship between prosthesis and terminal device type and satisfaction, controlling for covariates that were meaningful in bivariate analyses.

RESULTS

There were no differences in satisfaction by prosthesis type or terminal device degrees of freedom. Satisfaction was associated with receipt of training to use the initial prosthesis, amputation level, age, and race.

CONCLUSION

No differences in satisfaction by device or terminal device type were observed. Worse satisfaction was associated with more proximal amputation level, younger age, and black race. The association between receipt of initial prosthetic training and device satisfaction points to the critical role of occupational or physical therapy in the early stages of prosthetic care.

CLINICAL RELEVANCE

Prosthetic satisfaction did not vary by device or terminal device degrees of freedom. Proximal amputation level, younger age, and black race were associated with lower prosthetic satisfaction. Receipt of initial prosthetic training was associated with greater device satisfaction, pointing to the critical role and lasting impact of early training.

Obstacles to Prosthetic Care—Legal and Ethical Aspects of Access to Upper and Lower Limb Prosthetics in Germany and the Improvement of Prosthetic Care from a Social Perspective

Prosthetic technology for people with missing limbs has made great progress in recent decades. However, acceptance rates and user satisfaction are not only dependent on technical aspects, but also to a great extent on social and psychological factors. We propose that these factors should receive greater attention in order to improve prosthetic care and give recommendations how to incorporate the findings from social science in research and development (R&D) and in care practice. Limited access due to high costs of new prosthetic technology combined with rising costs in health care systems in general is a further issue we address. Our legal and ethical analysis of the reimbursement process in Germany shows that this issue requires further empirical investigation, a stakeholder dialogue and maybe even policy changes. Social science knowledge and participatory methods are of high relevance to answer questions about the benefit of prosthetics for users, based on individual needs and preferences, which should be at the core of debates on ethical resource allocation.

Assessment of body-powered 3D printed partial finger prostheses: a case study

BACKGROUND

Traditional prosthetic fabrication relies heavily on plaster casting and 3D models for the accurate production of prosthetics to allow patients to begin rehabilitation and participate in daily activities. Recent technological advancements allow for the use of 2D photographs to fabricate individualized prosthetics based on patient anthropometrics. Additive manufacturing (i.e. 3D printing) enhances the capability of prosthesis manufacturing by significantly increasing production speed and decreasing production cost. Existing literature has extensively described the validity of using computer-aided design and 3D printing for fabrication of upper limb prostheses. The present investigation provides a detailed description of the development of a patient specific body-powered 3D printed partial finger prosthesis and compares its qualitative and functional characteristics to a commercially available finger prosthesis.

CASE PRESENTATION

A 72-year old white male with a partial finger amputation at the proximal interphalangeal joint of the left hand performed a simple gross motor task with two partial finger prostheses and completed two self-reported surveys (QUEST & OPUS). Remote fitting of the 3D printed partial finger began after receipt of 2D photographs of the patient's affected and non-affected limbs. Prosthetic fitting when using 3D printable materials permitted the use of thermoforming around the patient's residual limb, allowing for a comfortable but tight-fitting socket. Results of the investigation show improved performance in the Box and Block Test when using both prostheses (22 blocks per minute) as compared to when not using a prosthesis (18 blocks per minute). Both body-powered prostheses demonstrated slightly lower task-efficiency when compared to the non-affected limb (30 blocks per minute) for the gross motor task. Results of the QUEST and OPUS describe specific aspects of both prostheses that are highly relevant to quality of life and functional performance when using partial finger prostheses.

CONCLUSION

The use of 3D printing exhibits great potential for the fabrication of functional partial finger prostheses that improve function in amputees. In addition, 3D printing provides an alternative means for patients located in underdeveloped or low-income areas to procure a functional finger prosthesis.

Perceptions of ability among adults with upper limb absence: impacts of learning, identity, and community

Aims: The purpose of this research was to examine the lived experiences of adults with upper limb absence, specifically the interplay of device use, ability, and quality of life through semi-structured interviews. We sought to draw insight from these experiences to improve the practice and perceptions of adults with upper limb absence, prosthetists, and technology designers.Methods: Semi-structured interviews were conducted and interpreted with phenomenological analysis for fourteen individuals with acquired or congenital limb absence. Through an interpretive phenomenological analysis approach, researchers employed an inductive approach to coding and identification of central themes.Results: Participants shared high perceptions of ability and function, regardless of prosthesis or assistive technology use. Life experiences related to three dimensions strongly influenced perceptions of ability: (1) learning to live with upper limb absence, (2) developing their identity, and (3) connecting with their community. The diversity of experiences across participants highlighted the limitations of identifying "normative" pathways of recovery or device use, emphasizing the need for flexible and adaptable systems that can creatively support personal goals and needs.Conclusions: Integration of novel platforms for professional practice, supportive communities, and technology innovation can support the evolving needs and care of individuals with upper limb absence.Implications for rehabilitationIn this study, perceptions of ability were largely independent of prosthetic use and each individual developed a unique toolkit of devices and strategies to support function in daily life.Clinicians can support perceptions of ability by promoting opportunities for community development and life-long learning.Informal communities, such as online networks, can provide novel device designs, resources for learning, and societal awareness to empower individuals with limb absence.

The SoftHand Pro: Functional evaluation of a novel, flexible, and robust myoelectric prosthesis

Roughly one quarter of active upper limb prosthetic technology is rejected by the user, and user surveys have identified key areas requiring improvement: function, comfort, cost, durability, and appearance. Here we present the first systematic, clinical assessment of a novel prosthetic hand, the SoftHand Pro (SHP), in participants with transradial amputation and age-matched, limb-intact participants. The SHP is a robust and functional prosthetic hand that minimizes cost and weight using an underactuated design with a single motor. Participants with limb loss were evaluated on functional clinical measures before and after a 6-8 hour training period with the SHP as well as with their own prosthesis; limb-intact participants were tested only before and after SHP training. Participants with limb loss also evaluated their own prosthesis and the SHP (following training) using subjective questionnaires. Both objective and subjective results were positive and illuminated the strengths and weaknesses of the SHP. In particular, results pre-training show the SHP is easy to use, and significant improvement in the Activities Measure for Upper Limb Amputees in both groups following a 6-8 hour training highlights the ease of learning the unique features of the SHP (median improvement: 4.71 and 3.26 and p = 0.009 and 0.036 for limb loss and limb-intact groups, respectively). Further, we found no difference in performance compared to participant's own commercial devices in several clinical measures and found performance surpassing these devices on two functional tasks, buttoning a shirt and using a cell phone, suggesting a functional prosthetic design. Finally, improvements are needed in the SHP design and/or training in light of poor results in small object manipulation. Taken together, these results show the promise of the SHP, a flexible and adaptive prosthetic hand, and pave a path forward to ensuring higher functionality in future.

Does the DEKA Arm substitute for or supplement conventional prostheses

BACKGROUND

Research on home use of advanced upper limb prostheses is needed.

OBJECTIVES

To describe and compare DEKA Arm usage patterns during the last 4 weeks of a home trial for participants with a personal prosthesis and those without. To compare usage patterns during home trial to those of the personal prosthesis prior to home trial. To evaluate user activity preferences for the DEKA Arm and personal prosthesis after a trial of home use.

STUDY DESIGN

Quasi-experimental, time-series design.

METHODS

Data from 17 participants were analyzed. At baseline, prosthesis users reported days and hours they wore and used personal device(s). Home trial diaries documented days and hours of wear and use for the DEKA Arm and personal device(s), if applicable. Questionnaires asked prosthesis users to list activities they could do with the DEKA Arm but not with their current prosthesis and vice versa and activities they preferred doing with either devices.

RESULTS

The DEKA Arm was worn 81% and used 73% of functioning days, averaging 4.2 h worn and 2.4 h used on days worn. During home trial, prosthesis users used personal devices and any prosthesis for fewer hours/day than at baseline.

CONCLUSION

The DEKA supplemented but did not substitute for the personal prosthesis. Clinical relevance Findings strongly suggest that given the limitations of the DEKA Arm and conventional prosthesis, persons with upper limb amputation would be best served and would be able to perform the widest range of activities if they had several types of devices.

Development and Psychometric Validation of Capacity Assessment of Prosthetic Performance for the Upper Limb (CAPPFUL)

OBJECTIVES

(1) To develop a performance-based measure for adult upper limb (UL) prosthetic functioning through broad (ie, overall performance) and functional domain-specific (eg, control skills) assessment of commonplace activities; (2) to conduct initial psychometric evaluation of the Capacity Assessment of Prosthetic Performance for the Upper Limb (CAPPFUL).

DESIGN

Internal consistency of CAPPFUL and interrater reliability for task, functional domain, and full-scale (sub)scores among 3 independent raters were estimated. Known-group validity was examined comparing scores by amputation level. Convergent validity was assessed between CAPPFUL and 2 hand dexterity or function tests; discriminant validity was assessed against self-reported disability.

SETTING

Six prosthetic rehabilitation centers across the United States.

PARTICIPANTS

Subjects (N=60) with UL amputation using a prosthesis.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Not applicable.

RESULTS

Interrater reliability was excellent for scoring on the task, domain, and full-scale scores (intraclass correlation coefficients=.88-.99). Internal consistency was good (α=.79-.82). Generally, subjects with higher UL amputation levels scored lower (worse) than subjects with lower UL amputation levels. CAPPFUL demonstrated strong correlations with measures of hand dexterity or functioning (r_s=-.58 to .72) and moderate correlation with self-reported disability (r=-.35).

CONCLUSIONS

CAPPFUL was designed as a versatile, low-burden measure of prosthesis performance for any UL functional prosthetic device type and any UL amputation level. CAPPFUL assesses overall performance and 5 functional performance domains during completion of 11 tasks that require movement in all planes while manipulating everyday objects requiring multiple grasp patterns. Psychometric evaluation indicates good interrater reliability, internal consistency, known-group validity, and convergent and discriminant validity.

Feminine identity and functional benefits are key factors in women's decision making about upper limb prostheses: a case series

PURPOSE

Although the DEKA Arm promises new abilities, it is unclear if women with upper limb amputation are willing to avail themselves of this new technology. The study purpose was to understand key factors and tradeoffs that shape women's attitudes towards the DEKA Arm.

METHODS

This case series includes three women with transradial amputation. Structured surveys and semi-guided interviews were administered after completion of in-laboratory training and a home trial of the DEKA Arm. A constant comparative method with a grounded theory approach was used to generate a model describing women's decision-making related to the DEKA Arm. Quantitative data on prosthetic satisfaction was used to triangulate findings.

RESULTS

Factors that enhanced desirability of the DEKA Arm were improved functionality, increased abilities and the availability of someone to service the prosthesis. Factors that detracted from desirability of the device were its appearance, conspicuousness, lifestyle incompatibility, weight, need for service and difficulty of use. Each woman weighted these factors within the larger context of the capabilities of and satisfaction with her personal prostheses, her self-concept and lifestyle needs. Situational demands, particularly the desire to appear feminine and professional or need to perform certain activities, also altered the valuation of these priorities.

CONCLUSION

Findings strongly suggest that advanced upper limb prosthetic technologies, like the DEKA Arm, will be better accepted by women if appropriately gendered in appearance and designed with women's priorities in mind. Implications for Rehabilitation Women should be able to derive the functional benefits of advances in upper limb technology without needing to compromise their feminine identity and lifestyle preferences. Advanced upper limb prosthetic technologies will be better accepted by women if they are appropriately gendered.

Three-dimensional printed upper-limb prostheses lack randomised controlled trials: A systematic review

BACKGROUND

Three-dimensional printing provides an exciting opportunity to customise upper-limb prostheses.

OBJECTIVE

This review summarises the research that assesses the efficacy and effectiveness of three-dimensional printed upper-limb prostheses.

STUDY DESIGN

Systematic review.

METHODS

PubMed, Web of Science and OVID were systematically searched for studies that reported human trials of three-dimensional printed upper-limb prostheses. The studies matching the language, peer-review and relevance criteria were ranked by level of evidence and critically appraised using the Downs and Black Quality Index.

RESULTS

After removing duplicates, 321 records were identified. Eight papers met the inclusion criteria. No studies used controls; five were case studies and three were small case-series studies. All studies showed promising results, but none demonstrated external validity, avoidance of bias or statistically significant improvements over conventional prostheses. The studies demonstrated proof-of-concept rather than assessing efficacy, and the devices were designed to prioritise reduction of manufacturing costs, not customisability for comfort and function.

CONCLUSION

The potential of three-dimensional printing for individual customisation has yet to be fully realised, and the efficacy and effectiveness to be rigorously assessed. Until randomised controlled trials with follow-up are performed, the comfort, functionality, durability and long-term effects on quality of life remain unknown. Clinical relevance Initial studies suggest that three-dimensional printing shows promise for customising low-cost upper-limb prosthetics. However, the efficacy and effectiveness of these devices have yet to be rigorously assessed. Until randomised controlled trials with follow-up are performed, the comfort, functionality, durability and long-term effects on patient quality of life remain unknown.

The influence of environment: Experiences of users of myoelectric arm prosthesis-a qualitative study

BACKGROUND

Prostheses are used to varying degrees; however, little is known about how environmental aspects influence this use.

OBJECTIVES

To describe users' experiences of how environmental factors influence their use of a myoelectric arm prosthesis.

STUDY DESIGN

Qualitative and descriptive.

METHODS

A total of 13 patients previously provided with a myoelectric prosthetic hand participated. Their age, sex, deficiency level, etiology, current prosthesis use, and experience varied. Semi-structured interviews were audiotaped, transcribed, and analyzed through inductive content analysis.

RESULTS

Four categories were created from the data: "Prosthesis function," "Other people's attitudes," "Support from family and healthcare," and "Individual's attitude and strategies." The overarching theme, "Various degrees of embodiment lead to different experiences of environmental barriers and facilitators," emerged from differences in individual responses depending on whether the individual was a daily or a non-daily prosthesis user. Environmental facilitators such as support from family and healthcare and good function and fit of the prosthesis seemed to help the embodiment of the prosthesis, leading to daily use. This embodiment seemed to reduce the influence of environmental barriers, for example, climate, attitudes, and technical shortcomings.

CONCLUSION

Embodiment of prostheses seems to reduce the impact of environmental barriers. Support and training may facilitate the embodiment of myoelectric prosthesis use. Clinical relevance For successful prosthetic rehabilitation, environmental factors such as support and information to the patient and their social network about the benefits of prosthesis use are important. Local access to training in myoelectric control gives more people the opportunity to adapt to prosthesis use and experience less environmental barriers.

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

BACKGROUND

Prosthetic arm research predominantly focuses on "bionic" but not body-powered arms. However, any research orientation along user needs requires sufficiently precise workplace specifications and sufficiently hard testing. Forensic medicine is a demanding environment, also physically, also for non-disabled people, on several dimensions (e.g., distances, weights, size, temperature, time).

METHODS

As unilateral below elbow amputee user, the first author is in a unique position to provide direct comparison of a "bionic" myoelectric iLimb Revolution (Touch Bionics) and a customized body-powered arm which contains a number of new developments initiated or developed by the user: (1) quick lock steel wrist unit; (2) cable mount modification; (3) cast shape modeled shoulder anchor; (4) suspension with a soft double layer liner (Ohio Willowwood) and tube gauze (Molnlycke) combination. The iLimb is mounted on an epoxy socket; a lanyard fixed liner (Ohio Willowwood) contains magnetic electrodes (Liberating Technologies). An on the job usage of five years was supplemented with dedicated and focused intensive two-week use tests at work for both systems.

RESULTS

The side-by-side comparison showed that the customized body-powered arm provides reliable, comfortable, effective, powerful as well as subtle service with minimal maintenance; most notably, grip reliability, grip force regulation, grip performance, center of balance, component wear down, sweat/temperature independence and skin state are good whereas the iLimb system exhibited a number of relevant serious constraints.

CONCLUSIONS

Research and development of functional prostheses may want to focus on body-powered technology as it already performs on manually demanding and heavy jobs whereas eliminating myoelectric technology's constraints seems out of reach. Relevant testing could be developed to help expediting this. This is relevant as Swiss disability insurance specifically supports prostheses that enable actual work integration. Myoelectric and cosmetic arm improvement may benefit from a less forgiving focus on perfecting anthropomorphic appearance.

Grasp Performance of a Soft Synergy-Based Prosthetic Hand: A Pilot Study

Current prosthetic hands are frequently rejected in part due to limited functionality and versatility. We assessed the feasibility of a novel prosthetic hand, the SoftHand Pro (SHP), whose design combines soft robotics and hand postural synergies. Able-bodied subjects ( ) tracked cursor motion by opening and closing the SHP and performed a grasp-lift-hold-release (GLHR) task with a sensorized cylindrical object of variable weight. The SHP control was driven by electromyographic (EMG) signals from two antagonistic muscles. Although the time to perform the GLHR task was longer for the SHP than native hand for the first few trials (10.2 ± 1.4 s and 2.13 ± 0.09 s, respectively), performance was much faster on subsequent trials (~5 s). The SHP steady-state grip force was significantly modulated as a function of object weight ( ). For the native hand, however, peak and steady-state grip forces were modulated to a greater extent (+68% and +91%, respectively). These changes were mediated by the modulation of EMG amplitude and co-contraction. These data suggest that the SHP has a promise for prosthetic applications and point-to-design modifications that could improve the SHP.

Factors associated with interest in novel interfaces for upper limb prosthesis control

BACKGROUND

Surgically invasive interfaces for upper limb prosthesis control may allow users to operate advanced, multi-articulated devices. Given the potential medical risks of these invasive interfaces, it is important to understand what factors influence an individual's decision to try one.

METHODS

We conducted an anonymous online survey of individuals with upper limb loss. A total of 232 participants provided personal information (such as age, amputation level, etc.) and rated how likely they would be to try noninvasive (myoelectric) and invasive (targeted muscle reinnervation, peripheral nerve interfaces, cortical interfaces) interfaces for prosthesis control. Bivariate relationships between interest in each interface and 16 personal descriptors were examined. Significant variables from the bivariate analyses were then entered into multiple logistic regression models to predict interest in each interface.

RESULTS

While many of the bivariate relationships were significant, only a few variables remained significant in the regression models. The regression models showed that participants were more likely to be interested in all interfaces if they had unilateral limb loss (p ≤ 0.001, odds ratio ≥ 2.799). Participants were more likely to be interested in the three invasive interfaces if they were younger (p < 0.001, odds ratio ≤ 0.959) and had acquired limb loss (p ≤ 0.012, odds ratio ≥ 3.287). Participants who used a myoelectric device were more likely to be interested in myoelectric control than those who did not (p = 0.003, odds ratio = 24.958).

CONCLUSIONS

Novel prosthesis control interfaces may be accepted most readily by individuals who are young, have unilateral limb loss, and/or have acquired limb loss However, this analysis did not include all possible factors that may have influenced participant's opinions on the interfaces, so additional exploration is warranted.

Hand Transplantation: Current concepts and management algorithm

Introducción. El trasplante de mano ha sido uno de los retos del siglo XXI, cuyo primer caso reportado ocurrió en 1964. En este campo se han hecho estudios y avances que permitieron explorar nuevas alternativas para el manejo del paciente con trasplante de mano, por lo que diversos centros de referencia han realizado análisis basados en sus experiencias, las cuales permitieron lograr la viabilidad de este tipo de trasplante.Objetivo. Esta revisión busca dar una visión general sobre el trasplante de mano y proponer un algoritmo de manejo.Materiales y métodos. La selección de candidatos requiere una serie de criterios, tales como evaluación clínica, paraclínica y psicosocial, desarrollados por un equipo multidisciplinario. La inmunosupresión busca evitar el rechazo y los inmunosupresores deben tener los niveles séricos apropiados para reducir sus efectos adversos. Se han reportado casos de rechazo agudo clásico y atípico, donde la piel es el principal tejido blanco, y rechazo crónico, en el cual se afectan los vasos sanguíneos. El seguimiento se realiza con varias pruebas, de modo que la de oro es la biopsia de piel.Resultados. Las complicaciones del tratamiento farmacológico derivan de la toxicidad de los medicamentos y se manifiestan como alteraciones metabólicas, infecciones oportunistas y neoplasias. La rehabilitación y los aspectos sociales, como el grado de satisfacción del paciente, deben ser evaluados durante la recuperación para asegurar adherencia al tratamiento. En 2011 el registro internacional de alotransplante compuesto de mano reportó 39 casos de trasplante de extremidades superiores con resultados variables; todo esto evidencia que para lograr un resultado óptimo y viable del trasplante debe realizarse seguimiento por un equipo multidisciplinario, red de apoyo del paciente y motivación del mismo, junto con el cumplimiento del manejo farmacológico.Conclusión. Se espera que nuevas investigaciones puedan crear estrategias para desarrollar tolerancia y, de esta forma, reducir el manejo mediante inmunosupresión.

Perceptions of satisfaction, usability and desirability of the DEKA Arm before and after a trial of home use

Objectives

To: 1) describe perceptions of satisfaction with and usability of the DEKA Arm and preferences for the DEKA Arm or personal prosthesis; 2) compare perceptions of satisfaction and usability by DEKA Arm configuration level; and 3) evaluate satisfaction and usability for study completers and non-completers; and for those who did and did not want to receive a DEKA Arm.

Methods

The study had 2 phases: in-laboratory (Part A) and home trial (Part B). 32 participants with amputation, (50% transradial, 38% transhumeral and 13% shoulder) completed Part A and 18 completed Part B 16 (89%) of whom were prosthesis users at baseline. Measures of satisfaction, usability and user preferences were administered. Responses were compared for completers of Part A only and completers of Parts A and B. Preferences for the DEKA Arm over personal prosthesis and proportion of participants who wanted to receive a DEKA Arm were evaluated. Relationships between satisfaction, usability and desire to receive a DEKA Arm were examined.

Results

At end of Part A, 22 (69%) of the 32 participants who completed in-laboratory training wanted to receive a DEKA Arm and 5 (16%) might want one. At end of Part B, 14 (88%) of 16 prosthesis users who completed the home trial preferred the overall function of the DEKA Arm, 13 (81%) preferred DEKA hand function and 14 (88%) preferred DEKA wrist function to their own prosthesis. In contrast, 14 (88%) preferred the weight and 13 (81%) preferred the look of their own prosthesis. Most aspects of the DEKA Arm were rated “easy” to use. No items were rated as “difficult”. Users were satisfied with most aspects of the DEKA Arm, except for the weight, shoulder appearance and harnessing. There were few differences in perceived usability or satisfaction by configuration level. Findings about desire to receive a DEKA Arm pertain only to study completers. Non-completers viewed the DEKA Arm less favorably than completers. Satisfaction was strongly related to participants’ expressed desire to receive a DEKA Arm in the future.

Significance

To maximize likelihood of adoption of the DEKA Arm, findings suggest that both an in-laboratory and a home use trial may be useful prior to finalizing a recommendation for prescription.

Predictors of retention and attrition in a study of an advanced upper limb prosthesis: implications for adoption of the DEKA Arm

PURPOSE

The purpose was to identify factors associated with completion of the VA home study of the DEKA Arm. Design and methodological procedures used: Differences between groups were examined using chi-square and t-tests. A multivariable logistic regression model predicting completion was generated and odds ratios (OR) for significant variables calculated. Post-hoc analysis was performed to plot the receiver operating characteristics (ROC) curve.

RESULTS

Participants who completed were more likely to be prosthesis users at study onset (p = .03), and less likely to have a history of musculoskeletal problems (p = .047). There were no statistically significant differences between groups who completed and those who did not in gender, race, veteran status, age, body mass index (BMI), weight, height, musculoskeletal pain at baseline, satisfaction with current prosthesis, type of prosthesis, or months of prosthesis use. Two variables, prosthesis use and history of musculoskeletal problems were significant at p < .10. The area under the curve (AUC) accuracy index was 0.78.

CONCLUSIONS

We considered completion of the home use study a reasonable proxy for participant willingness to adopt the device; and believe that findings can be extrapolated to guide DEKA Arm prescription recommendations. Participants most likely to complete the study were already using a personal prosthesis, and without pre-existing musculoskeletal problems. Implications for rehabilitation Data from the VA Study of the DEKA Arm were analysed to determine which factors were associated with likely successful adoption of the DEKA Arm. Participants most likely to complete the study were those who already using a personal prosthesis, and those without pre-existing chronic or re-occurring musculoskeletal problems. This information may be useful when attempting to identify and target the most appropriate candidates for DEKA Arm prescription.

Proof of Concept of an Online EMG-Based Decoding of Hand Postures and Individual Digit Forces for Prosthetic Hand Control

INTRODUCTION

Options currently available to individuals with upper limb loss range from prosthetic hands that can perform many movements, but require more cognitive effort to control, to simpler terminal devices with limited functional abilities. We attempted to address this issue by designing a myoelectric control system to modulate prosthetic hand posture and digit force distribution.

METHODS

We recorded surface electromyographic (EMG) signals from five forearm muscles in eight able-bodied subjects while they modulated hand posture and the flexion force distribution of individual fingers. We used a support vector machine (SVM) and a random forest regression (RFR) to map EMG signal features to hand posture and individual digit forces, respectively. After training, subjects performed grasping tasks and hand gestures while a computer program computed and displayed online feedback of all digit forces, in which digits were flexed, and the magnitude of contact forces. We also used a commercially available prosthetic hand, the i-Limb (Touch Bionics), to provide a practical demonstration of the proposed approach's ability to control hand posture and finger forces.

RESULTS

Subjects could control hand pose and force distribution across the fingers during online testing. Decoding success rates ranged from 60% (index finger pointing) to 83-99% for 2-digit grasp and resting state, respectively. Subjects could also modulate finger force distribution.

DISCUSSION

This work provides a proof of concept for the application of SVM and RFR for online control of hand posture and finger force distribution, respectively. Our approach has potential applications for enabling in-hand manipulation with a prosthetic hand.

Learning to use a body-powered prosthesis: changes in functionality and kinematics

BACKGROUND

Little is known about action-perception learning processes underlying prosthetic skills in body-powered prosthesis users. Body-powered prostheses are controlled through a harness connected by a cable that might provide for limited proprioceptive feedback. This study aims to test transfer of training basic tasks to functional tasks and to describe the changes over time in kinematics of basic tasks of novice body-powered prosthesis users.

METHODS

Thirty able-bodied participants and 17 controls participated in the study, using a body-powered prosthetic simulator. Participants in the training group were divided over four groups and practiced during a 2-week-period either direct grasping, indirect grasping, fixation, or a combination of these tasks. Deformable objects with different compliances had to be manipulated while kinematic variables and grip force control were assessed. Functional performance was measured with the Southampton Hand Assessment Procedure (SHAP) prior to and after the training sessions, and after 2 weeks and 3 months retention. The control group only performed the SHAP tests.

RESULTS

All four training groups and the control group improved on the SHAP, also after a period of non-use. Type of training had a small but significant influence on the improvements of the SHAP score. On a kinematic level movement times decreased and hook closing velocities increased over time. The indirect grasping group showed significantly shorter plateau times than the other training groups. Grip force control only improved a little over training.

CONCLUSIONS

Training action-perception couplings of body-powered prosthesis in basic tasks transferred to functional tasks and this lasted after a period of non-use. During training movement times decreased and the indirect grasping group showed advantages. It is advisable to start body-powered training with indirect grasping tasks but also to practice hook-object orientations.

Predicting prosthetic prescription after major lower-limb amputation

We describe prosthetic limb prescription in the first year following lower-limb amputation and examine the relationship between amputation level, geographic region, and prosthetic prescription. We analyzed 2005 to 2010 Department of Veterans Affairs (VA) Inpatient and Medical Encounters SAS data sets, Vital Status death data, and National Prosthetic Patient Database data for 9,994 Veterans who underwent lower-limb amputation at a VA hospital. Descriptive statistics and bivariates were examined. Cox proportional hazard models identified factors associated with prosthetic prescription. Analyses showed that amputation level was associated with prosthetic prescription. The hazard ratios (HRs) were 1.41 for ankle amputation and 0.46 for transfemoral amputation compared with transtibial amputation. HRs for geographic region were Northeast = 1.49, Upper Midwest = 1.26, and West = 1.39 compared with the South (p < 0.001). African American race, longer length of hospital stay, older age, congestive heart failure, paralysis, other neurological disease, renal failure, and admission from a nursing facility were negatively associated with prosthetic prescription. Being married was positively associated. After adjusting for patient characteristics, people with ankle amputation were most likely to be prescribed a prosthesis and people with transfemoral amputation were least likely. Geographic variation in prosthetic prescription exists in the VA and further research is needed to explain why.

Children with congenital limb deficiency in Norway: issues related to school life and health-related quality of life. A cross-sectional study

PURPOSE

To describe clinical features, issues related to school life and health-related quality of life (HRQOL) for children with congenital limb deficiency (CLD) and compare these children to Norwegian school children on HRQOL.

METHOD

Cross-sectional study. In 2010, a postal questionnaire, designed for this study and the Paediatric Quality of Life Inventory (PedsQL), was sent to 154 eligible parents of children with CLD, aged 6-18 years and registered at TRS National Resource Centre for Rare Disorders in Norway.

RESULTS

Response rate 44% (n = 67), median age 11 years, 42% were girls. Of the total group, 46 had unilateral upper limb deficiency (UULD) and 21 had multiple/lower limb deficiency (MLD/LLD). The most common UULD was below-elbow deficiency, of these, 65% used grip-improving devices, and 35% used prostheses. Children with UULD-reported PedsQL score similar to Norwegian schoolchildren (NSC). The MLD/LLD group was heterogeneous; most had below-elbow/knee deficiency. In this group, PedsQL scores were reduced for physical and social functioning compared with NSC. Compared with children with UULD, more children with MLD/LLD were restricted in participation because of pain and fewer participated in physical education with peers.

CONCLUSIONS

Most children with CLD participated with their peers and managed well in everyday life. Children with MLD/LLD seemed to have more challenges than children with UULD. Approximately one-third of all the children had assistive devices and/or practical assistance in school. Implications for Rehabilitation Most children with upper-limb deficiency (UULD) in Norway manage well in everyday life and have HRQOL equal to other Norwegian children. Many choose grip-improving devices instead of prostheses. Their preferences should be respected and taken into account as the need for new assistive devices arise. For children with pronounced disabilities, access to, and use of, assistive devices, adaptions and practical assistance may be important for participation. Cooperation with the child and the parents is necessary to find useful measures. Physical education and practical subjects may provide special challenges, both for children and their teachers. Children themselves often find good solutions and the tasks should be planned ahead in cooperation with them.

Task-Oriented Gaming for Transfer to Prosthesis Use

The aim of this study is to establish the effect of task-oriented video gaming on using a myoelectric prosthesis in a basic activity of daily life (ADL). Forty-one able-bodied right-handed participants were randomly assigned to one of four groups. In three of these groups the participants trained to control a video game using the myosignals of the flexors and extensors of the wrist: in the Adaptive Catching group participants needed to catch falling objects by opening and closing a grabber and received ADL-relevant feedback during performance. The Free Catching group used the same game, but without augmented feedback. The Interceptive Catching group trained a game where the goal was to intercept a falling object by moving a grabber to the left and right. They received no additional feedback. The control group played a regular Mario computer game. All groups trained 20 minutes a day for four consecutive days. Two tests were conducted before and after training: one level of the training game was performed, and participants grasped objects with a prosthesis simulator. Results showed all groups improved their game performance over controls. In the prosthesis-simulator task, after training the Adaptive Catching group outperformed the other groups in their ability to adjust the hand aperture to the size of the objects and the degree of compression of compressible objects. This study is the first to demonstrate transfer effects from a serious game to a myoelectric prosthesis task. The specificity of the learning effects suggests that research into serious gaming will benefit from placing ADL-specific constraints on game development.

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

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.

Changes in performance over time while learning to use a myoelectric prosthesis

BACKGROUND

Training increases the functional use of an upper limb prosthesis, but little is known about how people learn to use their prosthesis. The aim of this study was to describe the changes in performance with an upper limb myoelectric prosthesis during practice. The results provide a basis to develop an evidence-based training program.

METHODS

Thirty-one able-bodied participants took part in an experiment as well as thirty-one age- and gender-matched controls. Participants in the experimental condition, randomly assigned to one of four groups, practiced with a myoelectric simulator for five sessions in a two-weeks period. Group 1 practiced direct grasping, Group 2 practiced indirect grasping, Group 3 practiced fixating, and Group 4 practiced a combination of all three tasks. The Southampton Hand Assessment Procedure (SHAP) was assessed in a pretest, posttest, and two retention tests. Participants in the control condition performed SHAP two times, two weeks apart with no practice in between. Compressible objects were used in the grasping tasks. Changes in end-point kinematics, joint angles, and grip force control, the latter measured by magnitude of object compression, were examined.

RESULTS

The experimental groups improved more on SHAP than the control group. Interestingly, the fixation group improved comparable to the other training groups on the SHAP. Improvement in global position of the prosthesis leveled off after three practice sessions, whereas learning to control grip force required more time. The indirect grasping group had the smallest object compression in the beginning and this did not change over time, whereas the direct grasping and the combination group had a decrease in compression over time. Moreover, the indirect grasping group had the smallest grasping time that did not vary over object rigidity, while for the other two groups the grasping time decreased with an increase in object rigidity.

CONCLUSIONS

A training program should spend more time on learning fine control aspects of the prosthetic hand during rehabilitation. Moreover, training should start with the indirect grasping task that has the best performance, which is probably due to the higher amount of useful information available from the sound hand.

Opinions of youngsters with congenital below-elbow deficiency, and those of their parents and professionals concerning prosthetic use and rehabilitation treatment

Background

Youngsters with unilateral congenital below-elbow deficiency (UCBED) seem to function well with or without a prosthesis. Reasons for rejecting prostheses have been reported earlier, but unfortunately not those of the children themselves. Furthermore, reasons for acceptance are underexplored in the literature.

Objectives

To investigate opinions of children and early and late adolescents with UCBED, and those of their parents and healthcare professionals, concerning (1) reasons to wear or not to wear prostheses and (2) about rehabilitation care.

Methods

During one week of online focus group interviews, 42 children of 8–12 y/o, early and late adolescents of 13–16 and 17–20 y/o, 17 parents, and 19 healthcare professionals provided their opinions on various topics. This study addresses prosthetic use or non-use of prosthetics and rehabilitation care. Data were analyzed using the framework approach.

Results

Cosmesis was considered to be the prime factor for choosing and wearing a prosthesis, since this was deemed especially useful in avoiding stares from others. Although participants functioned well without prostheses, they agreed that it was an adjuvant in daily-life activities and sports. Weight and limited functionality constituted rejection reasons for a prosthesis. Children and adolescents who had accepted that they were different no longer needed the prosthesis to avoid being stared at. The majority of participants highly valued the peer-to-peer contact provided by the healthcare professionals.

Conclusions

For children and adolescents with UCBED, prostheses appeared particularly important for social integration, but much less so for functionality. Peer-to-peer contact seemed to provide support during the process of achieving social integration and should be embedded in the healthcare process.

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

PURPOSE

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.

METHOD

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.

RESULTS

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.

CONCLUSIONS

Most major ULAs wear prostheses. Individualised prosthetic training and fitting of myoelectric rather than passive prostheses may increase actual prosthesis use in ADL.

Musculoskeletal pain and overuse syndromes in adult acquired major upper-limb amputees

OBJECTIVES

(1) To compare the prevalence of self-reported musculoskeletal pain in upper-limb amputees (ULAs) in Norway with that of a control group drawn from the Norwegian general population; (2) to describe musculoskeletal pain bothersomeness in ULAs; (3) to estimate the association between prosthesis wear and self-reported musculoskeletal pain in ULAs; and (4) to describe the occurrence of musculoskeletal overuse syndromes in a sample of ULAs.

DESIGN

Cross-sectional study: postal questionnaires and clinical examinations.

SETTING

Norwegian ULA population. Clinical examinations performed at 3 clinics.

PARTICIPANTS

Questionnaires: population-based amputee sample (n=224; 57.4% response rate). Random control sample (n=318; 33.1% response rate). Clinical examinations: combined referred sample and convenience sample (n=70; 83.3% of those invited). Survey inclusion criteria: adult, resident in Norway and mastering Norwegian (amputees and controls), acquired major upper-limb amputation (amputees only).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Self-reported musculoskeletal pain and pain bothersomeness. Self-reported pain in prosthesis wearers and nonwearers. Clinically assessed diagnoses of musculoskeletal overuse syndromes.

RESULTS

Self-reported musculoskeletal pain was more frequent in ULAs than in the control group except for lower back pain. In ULAs, 57.0% reported neck/upper back pain (odds ratio [OR]=2.56; 95% confidence interval [CI], 1.64-3.98), and 58.9% reported shoulder pain (OR=4.00; 95% CI, 2.51-6.36). The percentage difference for arm pain was 24.8% (P<.001). All pain was reported as bothersome. We found no difference in pain prevalence between prosthesis wearers and nonwearers. Musculoskeletal overuse syndromes were found in 6.1% to 24.2% of ULAs, depending on diagnosis and case-definition criteria.

CONCLUSIONS

Upper-limb loss increases the risk of self-reported musculoskeletal pain in the neck/upper back, shoulders, and in the remaining arm. Prosthesis wear does not prevent musculoskeletal pain. Further studies should be conducted to investigate the effects of prosthesis wear and possible preventive measures, and to ascertain our preliminary prevalence estimates of overuse syndromes.