Search

Despite the increasing incidence and prevalence of amputation across the globe, individuals with acquired limb loss continue to struggle with functional recovery and chronic pain. A more complete understanding of the motor and sensory remodeling of the peripheral and central nervous system that occurs postamputation may help advance clinical interventions to improve the quality of life for individuals with acquired limb loss. The purpose of this article is to first provide background clinical context on individuals with acquired limb loss and then to provide a comprehensive review of the known motor and sensory neural adaptations from both animal models and human clinical trials. Finally, the article bridges the gap between basic science researchers and clinicians that treat individuals with limb loss by explaining how current clinical treatments may restore function and modulate phantom limb pain using the underlying neural adaptations described above. This review should encourage the further development of novel treatments with known neurological targets to improve the recovery of individuals postamputation. [ABSTRACT FROM AUTHOR]

If the alignment of a leg prosthesis is inadequate there will be the danger of arthritic defects occurring in the preserved knee joint. Acoustic-kinetic joint analysis in orthopaedic technology allows monitoring of the knee joint of an amputee after the alignment of a leg prosthesis and to recognize early joint defects resulting in adaptation of the alignment of the prothesis. A test rig was developed which includes acoustic emission analysis of the knee, video-based gait analysis, ground reaction force measurement and the measurement of the holding forces of the hands. During the examination a subject must do 3 one-legged knee bends during 10 sec with the preserved leg. To support the subject two grab handles were fixed with force sensors to a frame. A series of 6 measurements were recorded with breaks of 2 min. The recorded forces of the leg show a double hump pattern during the knee bend. The rising edge of the flexion phase was not uniform. The forces show no conclusive uniform pattern. The fitness of the probands acts as an indicator for the pattern of the force signals. The signals of the measurements show the necessity of the support for both hands to execute a one-legged knee bend. The understanding of the 3 measured forces is important for the arthritic diagnosis of the knee joint. [ABSTRACT FROM AUTHOR]

The kinematics of the body center of mass (bCoM) may provide crucial information supporting the rehabilitation process of people with transfemoral amputation. The use of magneto-inertial measurement units (MIMUs) is promising as it may allow in-the-field bCoM motion monitoring. Indeed, bCoM acceleration might be obtained by fusing the estimated accelerations of body segments' centers of mass (sCoM), the formers being computed from the measured accelerations by segment-mounted MIMUs and the known relative position between each pair of MIMU and underlying sCoM. This paper investigates how erroneous identifications of MIMUs positions impact the accuracy of estimated 3D sCoM and bCoM accelerations in transfemoral amputee gait. Using an experimental design approach, 215 simulations of erroneous identifications of MIMUs positions (up to 0.02 m in each direction) were simulated over seven recorded gait cycles of one participant. MIMUs located on the trunk and sound lower limbs were shown to explain up to 77% of the variance in the accuracy of the estimated bCoM acceleration, presumably due to the higher mass and/or angular velocity of these segments during gait of lower-limb amputees. Therefore, a special attention should be paid when identifying the positions of MIMUs located on segments contributing the most to the investigated motion. Sensitivity of the estimated vertical body center of mass acceleration to erroneous identifications of MIMU positions in the anteroposterior (AP), mediolateral (ML), and vertical (V) directions, expressed in percentage of the total variance of the estimation accuracy. [ABSTRACT FROM AUTHOR]

Introduction: Patients who undergo extremity amputation have historically used socket prosthetics to ambulate and perform daily functions; however, these prosthetics can be limited by poor terminal control and wear issues. In patients who have difficulty wearing their prostheses or with upper extremity amputations, osseointegrated implants may offer better function and quality of life. The Osseointegrated Prostheses for the Rehabilitation of Amputees (OPRA) was the first such device to become commercially available. Clinical trials have demonstrated benefit in patient gait, prosthetic use, and overall well-being, and new implants may be applied for various amputation levels. Areas covered: The OPRA, the most studied osseointegrated prosthetic stem, is reviewed, presenting indications, surgical procedure, complications, and results of clinical studies. Expert commentary: Osseointegration for amputees is an expanding field that has the potential to enhance rehabilitative potential. The OPRA implant is an effective device with a long life-span and low complication profile. [ABSTRACT FROM AUTHOR]

This investigation compared stance, swing, and double support times of a recent below-the-knee amputee (BKA) child's gait with the gait of normal children and with that of experienced BKA children. Kinematic data were collected for 11 normal children, 2 experienced BKA children, and a novice BKA child. Results indicated there were significant differences between the steps of prosthetic and nonprosthetic limbs and between normals and BKAs. Initially the gait of the novice BKA differed from that of experienced BKAs. After 94 days the gait of the novice BKA was not significantly different from that of the experienced BKAs. It was concluded that since the structure and function of the prosthetic limb is not the same as normal, (a) it may be appropriate for the BKA child to have an asymmetrical gait pattern, and (b) rehabilitation may be directed toward teaching the recent BKA child to walk more like experienced BKAs than like normal children. [ABSTRACT FROM AUTHOR]

Background: Major lower-limb amputation (LLA) predisposes patients post-operatively to a significant decline in daily-life functioning. The physical condition of amputee patients prior to surgery is significantly deteriorated due to chronic peripheral vascular disease (PVD) and diabetes, which accounts for the majority of LLAs in the adult population. A common strategy called pre-rehabilitation has been used in multiple patient populations to prepare the patient for undergoing a surgical event and to improve post-operative patient outcomes. Pre-rehabilitation might enhance the outcome of dysvascular LLA patients and reduce the high post-operative mortality rates. However, experience of experts with pre-rehabilitation and feasibility of a pre-rehabilitation program in this group remains unknown. Objective: To investigate the experiences of medical professionals and researchers in the field of LLA with the use of pre-rehabilitation in general and in particular PVD patients. Additionally, the study examines their opinions regarding need for and feasibility of a pre-rehabilitation program for dysvascular patients at risk for an LLA. Methods: Two explorative focus group discussions were organized with in total 16 experts in the field of treatment and research of LLA. Transcribed data were coded using the Atlas.ti software package. Thematic analysis with inductive approach was opted to arrange and interpret codes. Results: The experiences of the experts with pre-rehabilitation in dysvascular patients were scarce. The experts described dysvascular patients at risk for an LLA as a difficult group for pre-rehabilitation due to short time window prior to surgery, older age, multiple co-morbidities and lack of motivation for behavioral change. The experts concluded that a pre-rehabilitation program should focus on patients who have sufficient time in advance before the amputation for pre-rehabilitation and who are motivated to participate. Conclusion: Although in general the effects of pre-rehabilitation are promising, pre-operative rehabilitation in dysvascular patients at risk for an LLA seems not feasible. Future research could focus on a better monitoring of dysvascular patients and the development of pre-rehabilitation in subgroups of younger dysvascular LLA patients. [ABSTRACT FROM AUTHOR]

Military members with war-related lower limb amputation experience a range of acute and chronic pain symptoms. The purpose of this study was to evaluate pain during 12 weeks of a military amputee rehabilitation program ( MARP) pre- and post-prosthesis. The data for this study were drawn from a randomized clinical trial comparing MARP supplemented with neuromuscular electrostimulation ( MARP + NMES, n = 23) to MARP alone ( n = 21) for service members with unilateral transtibial amputation. The McGill Pain Questionnaire ( MPQ) and phantom limb pain/sensations were assessed at baseline, 3, 6, 9, and 12 weeks. Changes within- and between-groups were analyzed with generalized mixed models. Participants reported mild-to-moderate pain at all visits, and improved significantly on the MPQ and frequency of phantom limb pain/sensations ( p < .001 for effect of time). Group by time interactions were not significant, indicating both groups showed similar improvement. Univariate tests showed the NMES + MARP group had lower pain intensity than MARP-only group at weeks 3 and 6. Participants in MARP demonstrated good overall pain control and reported reduced pain and fewer days with phantom limb pain/sensations over 12 weeks. Adding NMES to MARP may be beneficial in early rehabilitation, and NMES could potentially enhance physical therapy participation by decreasing pain. [ABSTRACT FROM AUTHOR]

Background: The majority of lower limb amputations are undertaken in people with peripheral arterial occlusive disease, and approximately 50% have diabetes. Quality of life is an important outcome in lower limb amputations; little is known about what influences it, and therefore how to improve it.Objectives: The aim of this systematic review was to identify the factors that influence quality of life after lower limb amputation for peripheral arterial occlusive disease.Methods: MEDLINE, EMBASE, CINAHL, PsycINFO, Web of Science and Cochrane databases were searched to identify articles that quantitatively measured quality of life in those with a lower limb amputation for peripheral arterial occlusive disease. Articles were quality assessed by two assessors, evidence tables summarised each article and a narrative synthesis was performed.Study Design: Systematic review.Results: Twelve articles were included. Study designs and outcome measures used varied. Quality assessment scores ranged from 36% to 92%. The ability to walk successfully with a prosthesis had the greatest positive impact on quality of life. A trans-femoral amputation was negatively associated with quality of life due to increased difficulty in walking with a prosthesis. Other factors such as older age, being male, longer time since amputation, level of social support and presence of diabetes also negatively affected quality of life.Conclusion: Being able to walk with a prosthesis is of primary importance to improve quality of life for people with lower limb amputation due to peripheral arterial occlusive disease. To further understand and improve the quality of life of this population, there is a need for more prospective longitudinal studies, with a standardised outcome measure. Clinical relevance This is of clinical relevance to those who are involved in the rehabilitation of persons with lower limb amputations. Improved quality of life is associated with successful prosthetic use and focus should be directed toward achieving this. [ABSTRACT FROM AUTHOR]

Copyright of Medical Rehabilitation / Rehabilitacja Medyczna is the property of Medical Rehabilitation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: To overcome the challenges of rehabilitation of bilateral transfemoral amputees, we developed a novel "hip prosthesis in the sitting posture." Case Description and Methods: A 64-year-old male bilateral transfemoral amputee was transferred for rehabilitation 4 months following a burn injury. His wounds remained unhealed for 20 months; thus, he was unable to participate in standing training with the standard prosthetic sockets. Hip prosthesis in the sitting posture has very little friction between the sockets and residual limbs, which facilitated our patient to begin standing and walking exercises. Findings and Outcomes: The patient's refractory wounds healed 1 month after initiating exercises using hip prosthesis in the sitting posture, and he could begin rehabilitation with the standard prostheses.Discussion and Conclusion: Hip prosthesis in the sitting posture enabled a bilateral transfemoral amputee with unhealed residual limbs to stand, walk, and begin balance training. Hip prosthesis in the sitting posture is an effective temporary prosthesis to prevent disuse until wounds are healed and to continue rehabilitation with standard prostheses. Clinical relevance Hip prosthesis in the sitting posture is useful for bilateral transfemoral amputees with unhealed residual limbs after burn injuries to prevent disuse and maintain motivation for walking. [ABSTRACT FROM AUTHOR]

Background: This novel case report describes the problems of prescribing a prosthetic socket in a left transfemoral amputee secondary to chronic patellofemoral instability compounded by complex regional pain syndrome. Case Description and Methods: Following the amputation, complex regional pain syndrome symptoms recurred in the residual limb, presenting mainly with oedema. Due to extreme daily volume fluctuations of the residual limb, a conventional, laminated thermoplastic socket fitting was not feasible. Findings and Outcomes: An adjustable, modular socket design was trialled. The residual limb volume fluctuations were accommodated within the socket. Amputee rehabilitation could be continued, and the rehabilitation goals were achieved. The patient was able to wear the prosthesis for 8 h daily and to walk unaided indoors and outdoors.Conclusion: An adjustable, modular socket design accommodated the daily residual limb volume fluctuations and provided a successful outcome in this case. It demonstrates the complexities of socket fitting and design with volume fluctuations. Clinical relevance Ongoing complex regional pain syndrome symptoms within the residual limb can lead to fitting difficulties in a conventional, laminated thermoplastic socket due to volume fluctuations. An adjustable, modular socket design can accommodate this and provide a successful outcome. [ABSTRACT FROM AUTHOR]

Background: Most amputees live with their prostheses for a long time. Therefore, quality of life is an important outcome for lower limb amputees.Objective: To translate the Prosthesis Evaluation Questionnaire (PEQ) and evaluate psychometric properties.Study Design: Methodological research.Methods: Lower limb amputees responded to electronic versions of the PEQ and SF-36v2 at baseline (n=64), after two weeks (n=51), and after 12 weeks (n=50). Reliability was assessed using Cronbach's alpha and intraclass correlation coefficient (ICC) analyses of the baseline and two weeks test-retest data. Estimates for standard error of measurement (SEM) were calculated based on reliability estimates. Construct validity was evaluated by testing using hypotheses testing.Results: Reliability estimates (ICC/Cronbach's alpha) for the nine subscales were: Social Burden (0.85/0.76), Appearance (0.85/0.72), Residual Limb Health (0.80/0.69), Well-Being (0.78/0.90), Utility (0.76/0.89), Frustration (0.74/0.90), Perceived Response (0.62/0.80), Ambulation (0.61/0.94), Sounds (0.51/0.65). Construct validity was supported in three out of four subscales evaluated.Conclusions: The subscales Social Burden, Appearance, Well-Being, Utility and Frustration had consistent high reliability, supporting their use in assessing the prosthesis related quality of life in lower limb amputees. Results were mixed on three other scales (Residual Limb Health, Perceived Response, and Ambulation), while one scale, Sounds, had consistent low reliability. Clinical relevance For the first time a patient reported disease specific quality of life measure for lower limb amputees is available in Danish. Health care providers can now identify patients with reduced quality of life and measure treatment and rehabilitation effects over time. [ABSTRACT FROM AUTHOR]

Background: Balance is an important variable to consider during the rehabilitation process of individuals with trans-tibial amputation. Limited evidence exists on the balance abilities of people with trans-tibial amputation due to vascular causes.Objective: The purpose of this article is to review literature and determine if standing balance is diminished in people with trans-tibial amputation due to vascular causes.Study Design: Literature review.Methods: Data were obtained from PubMed, Google Scholar, OandP.org , CINHAL, and Science Direct. Studies were selected only if they included standing balance assessment of people with unilateral trans-tibial amputation due to vascular causes.Results: The review yielded seven articles that met the inclusion criteria. The general test methodology required participants to stand still on force platforms, with feet together, while center of pressure or postural sway was recorded.Conclusion: According to the findings of this review, individuals with trans-tibial amputees due to vascular causes have diminished balance abilities. Limited evidence suggests their balance might be further diminished as compared to individuals with trans-tibial amputation due to trauma. Although the evidence is limited, because of the underlying pathology and presence of comorbidities in individuals with trans-tibial amputation due to vascular causes, one cannot ignore these findings, as even a minor injury from a fall may develop into a non-healing ulcer and affect their health and well-being more severely than individuals with trans-tibial amputation due to trauma. Clinical relevance Individuals with trans-tibial amputation due to vascular causes have diminished balance abilities compared to healthy individuals and individuals with trans-tibial amputation due to trauma. This difference should be considered when designing and fabricating prostheses. Prosthetists and rehabilitation clinicians should consider designing amputation cause-specific rehabilitation interventions, focussing on balance and other functional limitations related to comorbidities of amputation. [ABSTRACT FROM AUTHOR]

Background: Capturing the variability that exists among patients attending an amputee clinic using standardized paper-based questionnaires is time-consuming and may not be practical for routine clinical use. Electronic questionnaires are a potential solution; however, the benefits are dependent on the feasibility and acceptance of this mode of data collection among patients.Objective: To determine the feasibility and patient preference/comfort in using a tablet-based questionnaire for data collection in an outpatient amputee rehabilitation clinic compared to a traditional paper-based questionnaire.Study Design: Observational study.Methods: In all, 48 patients with major extremity amputations completed both tablet and paper questionnaires related to their amputation and prosthetic use. Both trials were timed; patients then completed a semi-structured questionnaire about their experience.Results: In all, 20.5% of patients needed hands-on assistance completing the paper questionnaire compared to 20.8% for the tablet. The majority of participants (52.1%) indicated a preference for the tablet questionnaire; 64.6% of patients felt the tablet collected a more complete and accurate representation of their status and needs. In all, 70.8% of participants described themselves as comfortable using the tablet.Conclusion: Despite comorbidities, patients with amputations demonstrated excellent acceptance of the electronic tablet-based questionnaire. Tablet questionnaires have significant potential advantages over paper questionnaires and should be further explored. Clinical relevance A custom electronic questionnaire was found to be beneficial for routine clinic use and was well received by patients in an amputee rehabilitation clinic. Development of such questionnaires can provide an efficient mechanism to collect meaningful data that can be used for individual patient care and program quality improvement initiatives. [ABSTRACT FROM AUTHOR]

Background: Amputation of lower limb results in limitations in mobility which are amenable to multiple rehabilitation interventions. The challenges faced by the persons with lower limb amputation vary internationally. The International Classification of Functioning, Disability and Health provides a common language to describe the function of persons with lower limb amputation across various countries.Objectives: This article reports the concepts in mobility important to persons with lower limb amputation across six countries using the International Classification of Functioning, Disability and Health.Study Design: Qualitative study using focus groups and individual interviews.Methods: Focus groups and individual interviews of persons with lower limb amputation were organised across six countries to identify the issues faced by patients with an amputation during and after their amputation, subsequent rehabilitation and on an ongoing basis in their daily life. Meaningful concepts were extracted from the responses and linked to suitable second-level and where applicable third-level International Classification of Functioning, Disability and Health categories. International Classification of Functioning, Disability and Health categorical frequencies were analysed to represent the prevalence and spread of International Classification of Functioning, Disability and Health categories by location.Results: A total of 133 patients were interviewed. A large percentage (93%) of the identified concepts could be matched to International Classification of Functioning, Disability and Health categories for quantitative analysis.Conclusion: The important concepts in mobility were similar across different countries. The comprehensiveness of International Classification of Functioning, Disability and Health as a classification system for human function and its universality across the globe is demonstrated by the large proportion of the concepts contained in the interviews from across the study centres that could be matched to International Classification of Functioning, Disability and Health categories. Clinical relevance The activity and participation restrictions faced by a person with lower limb amputation vary internationally and are amenable to multiple rehabilitation interventions. The International Classification of Functioning, Disability and Health may provide a common language to report and quantify the various concepts important to the patient in their rehabilitation journey. [ABSTRACT FROM AUTHOR]

Background: Individuals with transtibial amputation are at increase risk of falling. The absence of an ankle joint and the associated musculature in these individuals can reduce clearance between the prosthetic foot and ground during the swing phase of gait, which may increase the risk of stumbling and in turn falling.Objectives: To associate minimum toe clearance during gait in the laboratory with community-based, trip-related stumbles by individuals with transtibial amputation using conventional feet.Study Design: Prospective cohort design; following quantitative gait analysis, participants completed electronic surveys to prospectively report stumbles and falls for 1 year thereafter.Methods: General community with gait analysis conducted within a motion analysis laboratory and prospective tracking of stumbles occurring in the community. A volunteer sample of eight unilateral, transtibial amputees that were K3 or K4 level ambulators and current patients at a local prosthetic clinic. All participants completed the entire 1-year follow-up study. Prosthetic-side minimum toe clearance while walking on a level treadmill at self-selected speed and self-reported trip-related stumbles in the community. Minimum toe clearance was defined as a local minimum of the vertical displacement of the toe from toe-off to heelstrike relative to its position during midstance.Results: Prosthetic-side minimum toe clearance was more than 50% lower for participants who reported one or more trip-related stumbles on that side compared with participants who reported zero trip-related stumbles on the prosthetic side (minimum toe clearance = 12.3 ± 0.8 mm vs 25.6 ± 5.4 mm, respectively; p = 0.036).Conclusion: This is the first study relating laboratory-based measures to prospective stumbles by prosthesis users. The results suggest that prosthesis users with low minimum toe clearance may be at increased risk of experiencing a trip-related stumble in the community. Given that frequent stumbling increases the risk of falling, future work is warranted on the effectiveness of interventions focused on minimum toe clearance on reducing fall risk. Clinical relevance Interventions to increase minimum toes clearance, which could include prescription of active dorsiflexing prostheses or gait training, may help reduce the risk of trip-related falls for individuals who report a history of trip-related stumbles. [ABSTRACT FROM AUTHOR]

Copyright of Avances en PsicologÍa Latinoamericana is the property of Colegio Mayor de Nuestra Senora del Rosario and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article considers the use of martial arts-based high intensity interval training (MA-HIIT) in the rehabilitation of combat amputees in the U.S. armed forces. Topics discussed include the benefits of a MA-HIIT program, the barriers to successful rehabilitation of the combat amputee, and some advances to the rehabilitation of the combat amputee that have been developed since the onset of the hostilities after the attacks of September 11, 2001.

A controller for a powered transfemoral prosthesis is presented, which can coordinate power delivery at the knee with the motion of the crankshaft on a bicycle. The controller continuously estimates the lengths of a four-bar linkage model through the application of a recursive least squares algorithm. The link lengths are used to estimate the angle of the bicycle crankshaft. With this measure, the delivery of knee torque is coordinated with the motion of the user. The controller is implemented on a prosthesis prototype and assessed on a transfemoral amputee subject ( N = 1). The subject exhibited a bilateral work asymmetry of 83.5% when cycling with his daily use prosthesis in a free-swing mode. When 60-N·m peak assistance was provided by the powered prosthesis, the bilateral work asymmetry was reduced to 11.4%. The subject's metabolic energy rate was measured for speed and power-matched cycling while the powered prosthesis provided zero assistance (i.e., turned off and providing its back-drive resistance) or 30-N·m peak assistance. Subject's metabolic energy rate decreased by 16.5% when receiving powered assistance relative to the zero-assistance condition. [ABSTRACT FROM PUBLISHER]

Background: The ability to walk with a prosthesis is the main objective of rehabilitation following amputation, and distance and speed of walking achieved are considered determining factors in amputees' perception of quality-of-life.Objectives: To assess walking abilities and improvement in gait distance and speed parameters in patients undergoing transfemoral amputation with a femoral implant that allows distal support of the residuum.Study Design: Experimental before-and-after study.Methods: Ten transfemoral amputation patients received a titanium implant that allowed distal weight bearing of the residuum within the socket. The post-intervention follow-up period was 14 months. We evaluated the functionality using a 2-min walk test and the physiological cost index.Results: The etiology of amputation was traumatic in six patients (60%). The mean 2-min walk test score was 98.4 ± 19.5 m prior to the femoral implant and 122.5 ± 26.1 m at 14 months ( p < 0.008), representing an improvement of 24.5%. The mean gait speed prior to the femoral implant was 0.82 ± 0.16 and 1.02 ± 0.21 m/s at 14 months ( p < 0.008). The physiological cost index showed no differences ( p < 0.55).Conclusion: The results of this study show an improvement in the distance walked and gait speed in amputees 14 months after having received a femoral implant. Clinical relevance This article provides additional insight into the use of a femoral implant that allows distal support of the residuum to improve walking abilities and gait distance and speed parameters in patients undergoing transfemoral amputation, mainly those of vascular origin. [ABSTRACT FROM AUTHOR]

Background: In product development for lower limb prosthetic devices, a set of special criteria needs to be met. Prosthetic devices have a direct impact on the rehabilitation process after an amputation with both perceived technological and psychological aspects playing an important role. However, available psychometric questionnaires fail to consider the important links between these two dimensions. In this article a probabilistic latent trait model is proposed with seven technical and psychological factors which measure satisfaction with the prosthesis. The results of a first study are used to determine the basic parameters of the statistical model. These distributions represent hypotheses about factor loadings between manifest items and latent factors of the proposed psychometric questionnaire.Methods: A study was conducted and analyzed to form hypotheses for the prior distributions of the questionnaire's measurement model. An expert agreement study conducted on 22 experts was used to determine the prior distribution of item-factor loadings in the model.Results: Model parameters that had to be specified as part of the measurement model were informed prior distributions on the item-factor loadings. For the current 70 items in the questionnaire, each factor loading was set to represent the certainty with which experts had assigned the items to their respective factors. Considering only the measurement model and not the structural model of the questionnaire, 70 out of 217 informed prior distributions on parameters were set.Conclusion: The use of preliminary studies to set prior distributions in latent trait models, while being a relatively new approach in psychological research, provides helpful information towards the design of a seven factor questionnaire that means to identify relations between technical and psychological factors in prosthetic product design and rehabilitation medicine. [ABSTRACT FROM AUTHOR]

Background: In transfemoral (TF) amputees, the forward propulsion of the prosthetic leg in swing has to be mainly carried out by hip muscles. With hip strength being the strongest predictor to ambulation ability, an active powered knee joint could have a positive influence, lowering hip loading and contributing to ambulation mobility. To assess this, gait of four TF amputees was measured for level walking, first while using a passive microprocessor-controlled prosthetic knee (P-MPK), subsequently while using an active powered microprocessor-controlled prosthetic knee (A-MPK). Furthermore, to assess long-term effects of the use of an A-MPK, a 4-weeks follow-up case study was performed.Methods: The kinetics and kinematics of the gait of four TF amputees were assessed while walking with subsequently the P-MPK and the A-MPK. For one amputee, a follow-up study was performed: he used the A-MPK for 4 weeks, his gait was measured weekly.Results: The range of motion of the knee was higher on both the prosthetic and the sound leg in the A-MPK compared to the P-MPK. Maximum hip torque (HT) during early stance increased for the prosthetic leg and decreased for the sound leg with the A-MPK compared to the P-MPK. During late stance, the maximum HT decreased for the prosthetic leg. The difference between prosthetic and sound leg for HT disappeared when using the A-MPK. Also, an increase in stance phase duration was observed. The follow-up study showed an increase in confidence with the A-MPK over time.Conclusions: Results suggested that, partially due to an induced knee flexion during stance, HT can be diminished when walking with the A-MPK compared to the P-MPK. The single case follow-up study showed positive trends indicating that an adaptation time is beneficial for the A-MPK. [ABSTRACT FROM AUTHOR]

This paper presents a review on design issues and solutions found in active lower limb prostheses. This review is based on a systematic literature search with a methodical search strategy. The search was carried out across four major technical databases and the retrieved records were screened for their relevance. A total of 21 different active prostheses, including 8 above-knee, 9 below-knee and 4 combined knee-ankle prostheses were identified. While an active prosthesis may help to restore the functional performance of an amputee, the requirements regarding the actuation unit as well as for the control system are high and the development becomes a challenging task. Regarding mechanical design and the actuation unit high force/torque delivery, high efficiency, low size and low weight are conflicting goals. The actuation principle and variable impedance actuators are discussed. The control system is paramount for a "natural functioning" of the prosthesis. The control system has to enable locomotion and should react to the amputee's intent. For this, multi-level control approaches are reviewed. [ABSTRACT FROM AUTHOR]

Context: Little is known about Libyan disability and rehabilitation services. Objectives: To describe workforce characteristics of the only functioning disability rehabilitation service in 2012 Libya. This was the Benghazi Rehabilitation and Handicap Center. The focus of the case study was the physical disability services including amputee care. Method: Organizational case study involving site visit, self-report workforce survey, and review of relevant policy, government and peak agency reports relevant to disability services. Results: The case study revealed that disability regulations in Libya focussed on social security entitlements and impairment focussed treatment. Community based rehabilitation or initiatives for social inclusion and participation were scant, creating problems for people requiring long term rehabilitation in the community. The center workforce continued to function in spite of conflict and in difficult circumstances. While expatriate staff left in the 2011 conflict, local staff retention was high. These workers were mono-lingual, had longevity of tenure, and a lack of qualification mobility. Some such as therapists and prosthetic technicians, had highly specialised skills requiring center facilities. The case study revealed: escalating patient demand; bed-block; and problems in supplies, capital and equipment maintenance. There were opportunities to increase capacity through: clinical and administrative staff training; development of inpatient facilities for women; discharge options for long-term male inpatients; and coordinated information systems. Of 232 eligible, n=72 staff, who participated in the survey (mean age was 39.4 years; n=40 males). Most therapists/ prosthetic technicians were male; most nurses/ administrative workers were female (p=.0001). The most common qualification across occupations was secondary school; 28.2% had intermediate secondary and 22.5% university degrees as their highest qualification. A third had been employed at the centre >20 years, >10 years and <10 years respectively. 42% worked as part of a team. Conclusion: The study provides an insight into issues affecting disability services and revealed areas for future post-conflict workforce development and opportunities for disability service capacity building particularly in relation to coordinated information systems, qualification upgrades, in-service training, and development of inpatient discharge options including community based rehabilitation and supported accommodation. [ABSTRACT FROM AUTHOR]

Background: Rehabilitation, which is essential for amputees with myoelectric hands, can improve the quality of daily life by remodeling the neuron network. In our study, we aim to develop a cerebral blood perfusion (CBF) single-photon emission computed tomography computer-aided (SPECT-CA) detection scheme to automatically locate the brain's activated regions after rehabilitation.Results: Five participants without forearms (three male, two female, mean age 51 ± 12.89 years, two missing the right side, and three missing the left side) were included in our study. In the clinical assessment, all of the participants received higher scores after training. The results of the SPM analysis indicated that CBF in the precentral gyrus, postcentral gyrus, frontal lobe, temporal lobe and cerebellum was significantly different among the five participants (P < 0.05). Moreover, SPECT-CA showed that the activated brain areas mainly included the precentral gyrus, postcentral gyrus, cerebellum and extensive cerebral cortex.Conclusion: Our study demonstrated that the CBF SPECT-CA method can detect the brain blood perfusion changes induced by rehabilitation with high sensitivity and accuracy. This method has great potential for locating the remodeled neuron regions of amputees with myoelectric hands after rehabilitation. [ABSTRACT FROM AUTHOR]

Lower limb amputees can use electrical activity from their residual muscles for myoelectric control of a powered prosthesis. The most common approach for myoelectric control is a finite state controller that identifies behavioral states and discrete changes in motor tasks. An alternative approach to state-based myoelectric control is continuous proportional myoelectric control where ongoing electrical activity has a proportional relationship to the prosthetic joint torque or power. To test the potential of continuous proportional myoelectric control for powered lower limb prostheses, we recruited five unilateral transtibial amputees to walk on a treadmill with an experimental powered prosthesis. Subjects walked using the powered prosthesis with and without visual feedback of their control signal in real time. Amputee subjects were able to adapt their residual muscle activation patterns to alter prosthetic ankle mechanics when we provided visual feedback of their myoelectric control signal in real time. During walking with visual feedback, subjects significantly increased their peak prosthetic ankle power (p = 0.02, ANOVA) and positive work (p = 0.02, ANOVA) during gait above their prescribed prosthesis values. However, without visual feedback, the subjects did not increase their peak ankle power during push off. These results show that amputee users were able to volitionally alter their prosthesis mechanics during walking, but only when given an explicit goal for their residual muscle motor commands. Future studies that examine the motor and learning capabilities of lower limb amputees using their residual muscles for continuous proportional myoelectric control are needed to determine the viability of integrating continuous high-level control with existing finite state prosthetic controllers. [ABSTRACT FROM PUBLISHER]

This paper describes a control approach that provides walking and standing functionality for a powered ankle prosthesis, and demonstrates the efficacy of the approach in experiments with a unilateral transtibial amputee subject. Both controllers incorporate a finite-state structure that emulates healthy ankle joint behavior via a series of piecewise passive impedance functions. The walking controller additionally modifies impedance parameters based on estimated cadence, while the standing controller modulates the ankle equilibrium angle in order to adapt to the ground slope and user posture, and the supervisory controller selects between the walking and standing controllers. The system is shown to reproduce several essential biomechanical features of the healthy joint during walking, particularly relative to a passive prosthesis, and is shown to adapt to various cadences. The system is also shown to adapt to slopes over a range of \pm 15^\circ, providing support to the user, as validated by quasi-static stiffness measurements recorded by the prosthesis. The subject is shown to place more weight on the powered prosthesis than on his passive prosthesis when standing on sloped surfaces, particularly at angles of 10^\circ or greater. The authors also demonstrated that the prosthesis typically began providing support within 1 s of initial ground contact. Further, the supervisory controller was shown to effectively switch between walking and standing, as well as determine ground slope just prior to the transition from the standing controller to the walking controller, where the estimated ground slope was accurate to within 1.25^\circ for all trials. [ABSTRACT FROM PUBLISHER]

Background: The devastating earthquake in Sichuan in 2008 has left many adolescent amputees. However, little research has been focused on the adolescent amputees who have high potential to return to premorbid activity level.Objectives: To investigate daily step activities and prosthesis-related quality of life of the adolescent transtibial and transfemoral amputees after the earthquake.Study Design: A prospective and descriptive study.Methods: A total of 21 adolescent unilateral amputees (11 transtibial and 10 transfemoral amputees) were recruited. Step Activity Monitors and Prosthesis Evaluation Questionnaire were used to assess patients over a 3-month period.Results: The average number of steps per day was 4577 ± 849 and 2551 ± 693 in transtibial and transfemoral amputees, respectively. Transtibial amputees had significantly higher (p < 0.05) levels of step activity than transfemoral amputees in all Step Activity Monitors measures. Prosthetic compliance was good with daily wearing time of above 12 h/day in both groups. Prosthesis Evaluation Questionnaire scores showed no significant difference between two groups.Conclusions: The subjective quality of life is similar for adolescent amputees across transtibial and transfemoral amputation levels. Higher levels of step activity of transtibial amputees suggest that they have had lower energy expenditure and more capacity for ambulation.Clinical Relevance: This article involves a unique subset of young amputees who have sustained traumatic amputations following a major natural disaster. It provides a better understanding on the daily activities and quality of life, and could assist in optimizing the prosthetic outcomes of this subset of populations. [ABSTRACT FROM AUTHOR]

Background: Recovering from trips is challenging for transfemoral amputees, and attempts often result in falls. Better understanding of the effects of the sensory-motor deficits brought by amputation and the functional limitations of prosthetic devices could help guide therapy and fall prevention mechanisms in prostheses. However, how transfemoral amputees attempt to recover from trips on the sound and prosthesis sides throughout swing phase is poorly understood.Methods: We tripped eight able-bodied subjects and eight unilateral transfemoral amputees wearing their prescribed prostheses. The protocol consisted of six repetitions of 6 and 4 points throughout swing phase, respectively. We compared recovery strategies in able-bodied, sound side and prosthesis side limbs. The number of kinematic recovery strategies used, when they were used throughout swing phase, and kinematic characteristics (tripped limb joint angles, bilateral trochanter height and time from foot arrest to foot strike) of each strategy were compared across limb groups. Non-parametric statistical tests with corrections for post-hoc tests were used.Results: Amputees used the same recovery strategies as able-bodied subjects on both sound and prosthesis sides, although not all subjects used all strategies. Compared to able-bodied subjects, amputees used delayed-lowering strategies less often from 30-60 % of swing phase on the sound side, and from 45-60 % of swing phase on the prosthesis side. Within-strategy kinematic differences occurred across limbs; however, these differences were not consistent across all strategies. Amputee-specific recovery strategies-that are not used by control subjects-occurred following trips on both the sound and prosthesis sides in mid- to late swing.Conclusions: Collectively, these results suggest that sensory input from the distal tripped leg is not necessary to trigger able-bodied trip recovery strategies. In addition, the differences between sound and prosthesis side recoveries indicate that the ability of the support leg might be more critical than that of the tripped leg when determining the response to a trip. The outcomes of this study have implications for prosthesis control, suggesting that providing correct and intuitive real-time selection of typical able-bodied recovery strategies by a prosthetic device when it is the tripped and the support limb could better enable balance recovery and avoid falls. [ABSTRACT FROM AUTHOR]

Background: Personal protection equipment, improved early medical care, and rapid extraction of the casualty have resulted in more injured service members who served in Afghanistan surviving after severe military trauma. Many of those who survive the initial trauma are faced with complex wounds such as multiple amputations. Although costs of care can be high, they have not been well quantified before. This is required to budget for the needs of the injured beyond their service in the armed forces. Question/purposes: The purposes of this study were (1) to quantify and describe the extent and nature of traumatic amputations of British service personnel from Afghanistan; and (2) to calculate an estimate of the projected long-term cost of this cohort. Methods: A four-stage methodology was used: (1) systematic literature search of previous studies of amputee care cost; (2) retrospective analysis of the UK Joint Theatre Trauma and prosthetic database; (3) Markov economic algorithm for healthcare cost and sensitivity analysis of results; and (4) statistical cost comparison between our cohort and the identified literature. Results: From 2003 to 2014, 265 casualties sustained 416 amputations. The average number of limbs lost per casualty was 1.6. The most common type of amputation was a transfemoral amputation (153 patients); the next most common amputation type was unilateral transtibial (143 patients). Using a Markov model of healthcare economics, it is estimated that the total 40-year cost of the UK Afghanistan lower limb amputee cohort is £288 million (USD 444 million); this figure estimates cost of trauma care, rehabilitation, and prosthetic costs. A sensitivity analysis on our model demonstrated a potential ± 6.19% variation in costs. Conclusions: The conflict in Afghanistan resulted in high numbers of complex injuries. Our findings suggest that a long-term facility to budget for veterans' health care is necessary. Clinical Relevance: Estimates here should be taken as the start of a challenge to develop sustained rehabilitation and recovery funding and provision. [ABSTRACT FROM AUTHOR]

Background: Transcutaneous electrical stimulation can provide amputees with tactile feedback for better manipulating an advanced prosthesis. In general, there are two ways to transfer the stimulus to the skin: somatotopical feedback (SF) that stimulates the phantom digit somatotopy on the stump and non-somatotopical feedback (NF) that stimulates other positions on the human body. Methods: To investigate the difference between SF and NF, electrotactile experiments were conducted on seven amputees. Electrical stimulation was applied via a complete phantom map to the residual limb (SF) and to the upper arm (NF) separately. The behavior results of discrimination accuracy and response time were used to examine: 1) performance differences between SF and NF for discriminating position, type and strength of tactile feedback; 2) performance differences between SF and NF for one channel (1C), three channels (3C), and five channels (5C). NASA-TLX standardized testing was used to determine differences in mental workload between SF and NF. Results: The grand-averaged discrimination accuracy for SF was 6% higher than NF, and the average response time for SF was 600 ms faster than NF. SF is better than NF for position, type, strength, and the overall modality regarding both accuracy and response time except for 1C modality (p < 0.001). Among the six modalities of stimulation channels, performance of 1C/SF was the best, which was similar to that of 1C/NF and 3C/SF; performance of 3C/NF was similar to that of 5C/SF; performance of 5C/NF was the worst. NASA-TLX scores indicated that mental workload increased as the number of stimulation channels increased. Conclusions: We quantified the difference between SF and NF, and the influence of different number of stimulation channels. SF was better than NF in general, but the practical issues such as the limited area of stumps could constrain the use of SF. We found that more channels increased the amount and richness of information to the amputee while fewer channels resulted in higher performance, and thus the 3C/SF modality was a good compromise. Based on this study, we provide possible solutions to the practical problems involving the implementation of tactile feedback for amputees. These results are expected to promote the application of SF and NF tactile feedback for amputees in the future. [ABSTRACT FROM AUTHOR]

Many upper limb amputees experience an incessant, post-amputation "phantom limb pain" and report that their missing limbs feel paralyzed in an uncomfortable posture. One hypothesis is that efferent commands no longer generate expected afferent signals, such as proprioceptive feedback from changes in limb configuration, and that the mismatch of motor commands and visual feedback is interpreted as pain. Non-invasive therapeutic techniques for treating phantom limb pain, such as mirror visual feedback (MVF), rely on visualizations of postural changes. Advances in neural interfaces for artificial sensory feedback now make it possible to combine MVF with a high-tech "rubber hand" illusion, in which subjects develop a sense of embodiment with a fake hand when subjected to congruent visual and somatosensory feedback. We discuss clinical benefits that could arise from the confluence of known concepts such as MVF and the rubber hand illusion, and new technologies such as neural interfaces for sensory feedback and highly sensorized robot hand testbeds, such as the "BairClaw" presented here. Our multi-articulating, anthropomorphic robot testbed can be used to study proprioceptive and tactile sensory stimuli during physical finger-object interactions. Conceived for artificial grasp, manipulation, and haptic exploration, the BairClaw could also be used for future studies on the neurorehabilitation of somatosensory disorders due to upper limb impairment or loss. A remote actuation system enables the modular control of tendon-driven hands. The artificial proprioception system enables direct measurement of joint angles and tendon tensions while temperature, vibration, and skin deformation are provided by a multimodal tactile sensor. The provision of multimodal sensory feedback that is spatiotemporally consistent with commanded actions could lead to benefits such as reduced phantom limb pain, and increased prosthesis use due to improved functionality and reduced cognitive burden. [ABSTRACT FROM AUTHOR]

Recent powered (or robotic) prosthetic legs independently control different joints and time periods of the gait cycle, resulting in control parameters and switching rules that can be difficult to tune by clinicians. This challenge might be addressed by a unifying control model used by recent bipedal robots, in which virtual constraints define joint patterns as functions of a monotonic variable that continuously represents the gait cycle phase. In the first application of virtual constraints to amputee locomotion, this paper derives exact and approximate control laws for a partial feedback linearization to enforce virtual constraints on a prosthetic leg. We then encode a human-inspired invariance property called effective shape into virtual constraints for the stance period. After simulating the robustness of the partial feedback linearization to clinically meaningful conditions, we experimentally implement this control strategy on a powered transfemoral leg. We report the results of three amputee subjects walking overground and at variable cadences on a treadmill, demonstrating the clinical viability of this novel control approach. [ABSTRACT FROM PUBLISHER]

An introduction is presented in which the authors discuss various reports within the issue on topics including gait recognition and control of lower limb prosthetic, biomechanical analysis for assessment of the utility of active prostheses, and virtual reality rehabilitation.

This contribution is concerned with joint angle calculation based on inertial measurement data in the context of human motion analysis. Unlike most robotic devices, the human body lacks even surfaces and right angles. Therefore, we focus on methods that avoid assuming certain orientations in which the sensors are mounted with respect to the body segments. After a review of available methods that may cope with this challenge, we present a set of new methods for: (1) joint axis and position identification; and (2) flexion/extension joint angle measurement. In particular, we propose methods that use only gyroscopes and accelerometers and, therefore, do not rely on a homogeneous magnetic field. We provide results from gait trials of a transfemoral amputee in which we compare the inertial measurement unit (IMU)-based methods to an optical 3D motion capture system. Unlike most authors, we place the optical markers on anatomical landmarks instead of attaching them to the IMUs. Root mean square errors of the knee flexion/extension angles are found to be less than 1° on the prosthesis and about 3° on the human leg. For the plantar/dorsiflexion of the ankle, both deviations are about 1°. [ABSTRACT FROM AUTHOR]

We developed an upper-limb power-assist exoskeleton actuated by pneumatic muscles. The exoskeleton included two metal links: a nylon joint, four size-adjustable carbon fiber bracers, a potentiometer and two pneumatic muscles. The proportional myoelectric control method was proposed to control the exoskeleton according to the user's motion intention in real time. With the feature extraction procedure and the classification (back-propagation neural network), an electromyogram (EMG)-angle model was constructed to be used for pattern recognition. Six healthy subjects performed elbow flexion-extension movements under four experimental conditions: (1) holding a 1-kg load, wearing the exoskeleton, but with no actuation and for different periods (2-s, 4-s and 8-s periods); (2) holding a 1-kg load, without wearing the exoskeleton, for a fixed period; (3) holding a 1-kg load, wearing the exoskeleton, but with no actuation, for a fixed period; (4) holding a 1-kg load, wearing the exoskeleton under proportional myoelectric control, for a fixed period. The EMG signals of the biceps brachii, the brachioradialis, the triceps brachii and the anconeus and the angle of the elbow were collected. The control scheme's reliability and power-assist effectiveness were evaluated in the experiments. The results indicated that the exoskeleton could be controlled by the user's motion intention in real time and that it was useful for augmenting arm performance with neurological signal control, which could be applied to assist in elbow rehabilitation after neurological injury. [ABSTRACT FROM AUTHOR]

The most important tool for controlling an industrial robotic arm is a teach pendant, which controls the robotic arm movement in work spaces and accomplishes teaching tasks. A good teaching tool should be easy to operate and can complete teaching tasks rapidly and effortlessly. In this study, a new teaching system is proposed for enabling users to operate robotic arms and accomplish teaching tasks easily. The proposed teaching system consists of the teach pen, optical markers on the pen, a motion capture system, and the pen tip estimation algorithm. With the marker positions captured by the motion capture system, the pose of the teach pen is accurately calculated by the pen tip algorithm and used to control the robot tool frame. In addition, Fitts' Law is adopted to verify the usefulness of this new system, and the results show that the system provides high accuracy, excellent operation performance, and a stable error rate. In addition, the system maintains superior performance, even when users work on platforms with different inclination angles. [ABSTRACT FROM AUTHOR]

Objective: To assess improvement in functional outcomes following prosthetic fitting after lower limb amputation using a lower extremity functional scale in a cohort of the Pakistani population. Study Design: Quasi experimental Study. Place and Duration of Study: Amputee rehabilitation ward (indoor) / OPD (out patient department) at Armed Forces Institute of Rehabilitation Medicine Rawalpindi. From August 2009 to August 2010. Patients and Methods: Study was carried out in the amputee rehabilitation ward of the Armed Forces Institute of Rehabilitation Medicine, Rawalpindi, Pakistan. Fifty two consenting lower limb amputees fulfilling the inclusion criteria were enrolled. All patients were provided with modular prosthesis followed by gait training and integrated amputee rehabilitation program. An assessment was done at 0, 4 and 12 weeks after the provision of prosthesis. Results were analyzed by SPSS Version 15. Results: Most of the patients were males (98.1%). Mean age was 30.17±9 years . Trauma was the main etiology (99%) followed by tumor (in only 1 patient who had osteosarcoma). Transtibial amputation level was the commonest (53.8%) followed by transfemoral in 32.7% patients and Syme's (7.7%). Lower extremity functional scale (LEFS) mean score in the first week was 35.56 (44.5% of maximum function), which improved to 49.40 (61.8% of maximum function) at week 4, and 59.27 (74.09% of maximum function) at the end of week 12. The p-value for each was 0.000. Conclusion: Early and multidisciplinary amputee rehabilitation improves the functional ambulation level, quality of life and satisfaction level of the individual. [ABSTRACT FROM AUTHOR]

C5/C6 tetraplegic patients and transhumeral amputees may be able to use voluntary shoulder motion as command signals for a functional electrical stimulation system or transhumeral prosthesis. Stereotyped relationships, termed “postural synergies,” among the shoulder, forearm, and wrist joints emerge during goal-oriented reaching and transport movements as performed by able-bodied subjects. Thus, the posture of the shoulder can potentially be used to infer the desired posture of the elbow and forearm joints during reaching and transporting movements. We investigated how well able-bodied subjects could learn to use a noninvasive command scheme based on inferences from these postural synergies to control a simulated transhumeral prosthesis in a virtual reality task. We compared the performance of subjects using the inferential command scheme (ICS) with subjects operating the simulated prosthesis in virtual reality according to complete motion tracking of their actual arm and hand movements. Initially, subjects performed poorly with the ICS but improved rapidly with modest amounts of practice, eventually achieving performance only slightly less than subjects using complete motion tracking. Thus, inferring the desired movement of distal joints from voluntary shoulder movements appears to be an intuitive and noninvasive approach for obtaining command signals for prostheses to restore reaching and grasping functions. [ABSTRACT FROM PUBLISHER]

The article focuses on the motor and sensory rehabilitation of patient who underwent lower limb amputation. It says that rehabilitation of amputated patient was based mainly on protesization and an early return to home and work. It states that the rehabilitation for amputees must be based on coordinated series, which includes the diagnostic, prognostic, and therapeutic interventions. It adds that based on a study by Sherman and colleagues, almost 78% of amputees experienced phantom limb pain.

In this study, we hypothesized that haptic feedback would enhance grip force control of surface electromyography (sEMG)-controlled prosthetic hands for targeted reinnervation (TR) amputees. A new miniature haptic device, a tactor, that can deliver touch, pressure, shear, and temperature sensation, allows modality-matching haptic feedback. TR surgery that creates sensory regions on the patient's skin that refer to the surface of the missing limb allows somatotopic-matching haptic feedback. This paper evaluates the hypothesis via an sEMG-controlled virtual prosthetic arm operated by TR amputees under diverse haptic feedback conditions. The results indicate that the grip force control is significantly enhanced via the haptic feedback. However, the simultaneous display of two haptic channels (pressure and shear) does not enhance, but instead degrades, grip force control. [ABSTRACT FROM AUTHOR]