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Phantom limb pain (PLP) represents a significant challenge after amputation. This study investigated the use of phantom motor execution (PME) and phantom motor imagery (PMI) facilitated by extended reality (XR) for the treatment of PLP. Both treatments used XR, but PME involved overt execution of phantom movements, relying on the decoding of motor intent using machine learning to enable real-time control in XR. In contrast, PMI involved mental rehearsal of phantom movements guided by XR. The study hypothesized that PME would be superior to PMI. A multicenter, double-blind, randomized controlled trial was conducted in 9 outpatient clinics across 7 countries. Eighty-one participants with PLP were randomly assigned to PME or PMI training. The primary outcome was the change in PLP, measured by the Pain Rating Index, from baseline to treatment cessation. Secondary outcomes included various aspects related to PLP, such as the rate of clinically meaningful reduction in pain (CMRP; >50% pain decrease). No evidence was found for superiority of overt execution (PME) over imagery (PMI) using XR. PLP decreased by 64.5% and 68.2% in PME and PMI groups, respectively. Thirty-seven PME participants (71%) and 19 PMI participants (68%) experienced CMRP. Positive changes were recorded in all other outcomes, without group differences. Pain reduction for PME was larger than previously reported. Despite our initial hypothesis not being confirmed, PME and PMI, aided by XR, are likely to offer meaningful PLP relief to most patients. These findings merit consideration of these therapies as viable treatment options and alternatives to pharmacological treatments.

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.

People with acquired upper limb loss or congenital limb reduction deficiency are often offered a myoelectric prosthesis to compensate for the missing hand. A common problem is the non-use of prostheses, and lack of training has been suggested as a reason for this. Today, myoelectric prosthetic hands are available with multiple grips to benefit the users, but these benefits have yet to be confirmed in daily activities. 

The overall aim of this thesis was to gather empirical evidence about the benefits and use of myoelectric arm prostheses, by investigating and describing the environmental factors influencing prosthesis use, describing a training method for the use of multi-grip prostheses and evaluating the effect of multigrip hands in daily activities. The users’ experience of environmental influences on prosthesis use were investigated in a survey (study I) and an interview study (study II). A scoping review of training methods for the use of multi-grip prostheses (study III) showed that training instructions are few and none were described in detail. Therefore, a new method for training, STAIR, was developed and described (study IV). This method was used when we investigated the benefits of multi-grip hands in a clinical trial (study V). We found that, after a period of structured training, users found the multi-grip prostheses beneficial for performing their daily activities and reducing their pain-related disability, and they reported an increase in prosthesis wearing time. 

In conclusion, prosthesis users experience most environmental barriers from the physical environment and from the prosthesis itself. Positive environmental factors, such as training and support from health care professionals, facilitate their adaptation to the prosthesis. When a prosthesis feels like a part of the user, the negative impact from the surrounding environment decreases. With a structured training method, it is possible to learn how to operate a multi-grip prosthesis and use it in daily activities. 

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.

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.

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.

INTRODUCTION: New prosthetic hands with advanced technology making it possible to perform many different grasps and positions are now available on the market. This new advanced technology is also difficult for users to control, and studies have shown that the new hand functions are not used to the extent expected (1).

The Örebro Centre for Limb Deficiency and Arm Prostheses has a long experience of prosthetic fitting for both children and adults. About 80% of the adults report daily prosthesis use (2). Today, many prosthesis users find the advanced prosthetic hands interesting and wish to have one. However, when introducing a new prosthetic hand with questionable merits, the reasons for these results need to be considered. In light of our experience from fittings in Örebro, we decided that the training programs for the new hand models were not comprehensive enough, and there was a need for the development of a new method for training.

AIMS: To design a training method for advanced hand prosthetic hands.

METHODS: We performed a review of existing training programs for advanced myoelectric prosthetic hands and combined this with a structured training program, and a treatment philosophy with early fitting and regular follow up used in Örebro.

RESULTS AND CONCLUSIONS: The training method comprises control training and performance of ADL’s. It follows a structured program based on the 14 steps described in the Skills Index Ranking Scale. The control training focuses on control of all different grasps available with the body in different positions: sitting, standing; with and without support of the arm. The ADL’s are chosen individually through a Canadian Occupational Performance Measure interview. The capacity to use different grasps and integrating the new prosthesis when performing ADL’s is evaluated through the Assessment of Capacity for Myoelectric Control. The method is based on regular support and feedback from an occupational therapist, with follow-ups weekly the first month and then monthly the following 3-6 months. The method has been used on patients with good results.

CONCLUSION: A new method is designed to fit the new multifunctional prosthetic hands. The method can be applied upon prescription of advanced multifunctional prosthetic hands to enhance the functional use of the hands.

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.