Phantom motor execution facilitated by machine learning and augmented reality as treatment for phantom limb pain: a single group, clinical trial in patients with chronic intractable phantom limb pain.

BACKGROUND: Phantom limb pain is a debilitating condition for which no effective treatment has been found. We hypothesised that re-engagement of central and peripheral circuitry involved in motor execution could reduce phantom limb pain via competitive plasticity and reversal of cortical reorganisation. METHODS: Patients with upper limb amputation and known chronic intractable phantom limb pain were recruited at three clinics in Sweden and one in Slovenia. Patients received 12 sessions of phantom motor execution using machine learning, augmented and virtual reality, and serious gaming. Changes in intensity, frequency, duration, quality, and intrusion of phantom limb pain were assessed by the use of the numeric rating scale, the pain rating index, the weighted pain distribution scale, and a study-specific frequency scale before each session and at follow-up interviews 1, 3, and 6 months after the last session. Changes in medication and prostheses were also monitored. Results are reported using descriptive statistics and analysed by non-parametric tests. The trial is registered at ClinicalTrials.gov, number NCT02281539. FINDINGS: Between Sept 15, 2014, and April 10, 2015, 14 patients with intractable chronic phantom limb pain, for whom conventional treatments failed, were enrolled. After 12 sessions, patients showed statistically and clinically significant improvements in all metrics of phantom limb pain. Phantom limb pain decreased from pre-treatment to the last treatment session by 47% (SD 39; absolute mean change 1·0 [0·8]; p=0·001) for weighted pain distribution, 32% (38; absolute mean change 1·6 [1·8]; p=0·007) for the numeric rating scale, and 51% (33; absolute mean change 9·6 [8·1]; p=0·0001) for the pain rating index. The numeric rating scale score for intrusion of phantom limb pain in activities of daily living and sleep was reduced by 43% (SD 37; absolute mean change 2·4 [2·3]; p=0·004) and 61% (39; absolute mean change 2·3 [1·8]; p=0·001), respectively. Two of four patients who were on medication reduced their intake by 81% (absolute reduction 1300 mg, gabapentin) and 33% (absolute reduction 75 mg, pregabalin). Improvements remained 6 months after the last treatment. INTERPRETATION: Our findings suggest potential value in motor execution of the phantom limb as a treatment for phantom limb pain. Promotion of phantom motor execution aided by machine learning, augmented and virtual reality, and gaming is a non-invasive, non-pharmacological, and engaging treatment with no identified side-effects at present. FUNDING: Promobilia Foundation, VINNOVA, Jimmy Dahlstens Fond, PicoSolve, and Innovationskontor Väst.

Effect of multi-grip myoelectric prosthetic hands on daily activities, pain-related disability and prosthesis use compared with single-grip myoelectric prostheses: A single-case study.

OBJECTIVE: To evaluate the effect of multi-grip myoelectric prosthetic hands on performance of daily activities, pain-related disability and prosthesis use, in comparison with single-grip myoelectric prosthetic hands.  Design: Single-case AB design. PATIENTS: Nine adults with upper-limb loss participated in the study. All had previous experience of single-grip myoelectric prostheses and were prescribed a prosthesis with multi-grip functions. METHODS: To assess the changes in daily activities, pain-related disability and prosthesis use between single-grip and multi-grip myoelectric prosthetic hands, the Canadian Occupational Performance Measure, Pain Disability Index, and prosthesis wearing time were measured at multiple time-points. Visual assessment of graphs and multi-level linear regression were used to assess changes in the outcome measures.  Results: At 6 months' follow-up self-perceived performance and satisfaction scores had increased, prosthesis wearing time had increased, and pain-related disability had reduced in participants with musculoskeletal pain at baseline. On average, 8 of the 11 available grip types were used. Most useful were the power grip, tripod pinch and lateral pinch.  Conclusion: The multi-grip myoelectric prosthetic hand has favourable effects on performance of, and satisfaction with, individually chosen activities, prostheses use and pain-related disability. A durable single-grip myoelectric prosthetic hand may still be needed for heavier physical activities. With structured training, a standard 2-site electrode control system can be used to operate a multi-grip myoelectric prosthetic hand.

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.

Attitudes is the most important environmental factor for use of powered mobility devices - users' perspectives.

Introduction: Different factors in the environment influence the use of powered wheelchairs or powered scooters, i.e. powered mobility devices (PMDs), but there is limited knowledge about how these factors interact and if any factor has a greater impact. According to the ICF the environment consists of five areas.Aim: To describe users' experiences of how environmental factors from all ICF areas influence the use of PMDs.Methods: Descriptive qualitative design including 14 interviews with PMD users, analyzed using inductive qualitative content analysis.Findings: Use of PMDs means a conditional freedom depending on the interaction of several environmental factors. Regardless of environmental factor the societal attitudes were always present, directly or indirectly, and influenced the participants' feeling of being included and involved in society. The environmental factors and how they influence PMD use are described in four categories, comprising the following subjects: societal attitudes, the service delivery process, accessibility to the physical environment and financial resources.Conclusion: The findings show that societal attitudes influence all other factors, directly by others people's attitudes, or indirectly by how legislation and guidelines are formulated, interpreted and applied. Therefore, a change of societal attitudes seems necessary to increase accessibility and participation for PMD users.

Environmental barriers to participation and facilitators for use of three types of assistive technology devices.

The aim was to compare the presence of environmental barriers to participation and facilitators for assistive technology (AT) use and study the relation between barriers and AT use in three different AT devices. A cross-sectional survey was conducted. Inclusion criteria were ≥one year of experience as a user of myoelectric prosthesis (MEP), powered mobility device (PMD), or assistive technology for cognition (ATC) and age 20-90 years. Overall, 156 participants answered the Swedish version of the Craig Hospital Inventory of Environmental Factors and a study-specific questionnaire on facilitating factors. Non-parametric tests were used for comparisons. Barriers to participation were lowest in MEP users (md=0.12; p>0.001), and highest in ATC users (md=1.56; p>0.001) with the least support for AT use (p>0.001 - p=0.048). A positive correlation between fewer barriers and higher use of MEP was seen (r=0.30, p=0.038). The greatest barriers to participation were Natural environment, Surroundings and Information, and the most support came from relatives and professionals. Support, training and education are vital in the use of AT. These factors may lead to a more sustained and prolonged use of AT and may enable increased participation. Future research should focus on interventions that meet the needs of people with cognitive disabilities.

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.

Phantom motor execution as a treatment for phantom limb pain: protocol of an international, double-blind, randomised controlled clinical trial.

INTRODUCTION: Phantom limb pain (PLP) is a chronic condition that can greatly diminish quality of life. Control over the phantom limb and exercise of such control have been hypothesised to reverse maladaptive brain changes correlated to PLP. Preliminary investigations have shown that decoding motor volition using myoelectric pattern recognition, while providing real-time feedback via virtual and augmented reality (VR-AR), facilitates phantom motor execution (PME) and reduces PLP. Here we present the study protocol for an international (seven countries), multicentre (nine clinics), double-blind, randomised controlled clinical trial to assess the effectiveness of PME in alleviating PLP. METHODS AND ANALYSIS: Sixty-seven subjects suffering from PLP in upper or lower limbs are randomly assigned to PME or phantom motor imagery (PMI) interventions. Subjects allocated to either treatment receive 15 interventions and are exposed to the same VR-AR environments using the same device. The only difference between interventions is whether phantom movements are actually performed (PME) or just imagined (PMI). Complete evaluations are conducted at baseline and at intervention completion, as well as 1, 3 and 6 months later using an intention-to-treat (ITT) approach. Changes in PLP measured using the Pain Rating Index between the first and last session are the primary measure of efficacy. Secondary outcomes include: frequency, duration, quality of pain, intrusion of pain in activities of daily living and sleep, disability associated to pain, pain self-efficacy, frequency of depressed mood, presence of catastrophising thinking, health-related quality of life and clinically significant change as patient's own impression. Follow-up interviews are conducted up to 6 months after the treatment. ETHICS AND DISSEMINATION: The study is performed in agreement with the Declaration of Helsinki and under approval by the governing ethical committees of each participating clinic. The results will be published according to the Consolidated Standards of Reporting Trials guidelines in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT03112928; Pre-results.