Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 7.321
Filtrar
1.
J Biomech Eng ; 145(2)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36149020

RESUMO

Active prostheses can provide net positive work to individuals with amputation, offering more versatility across locomotion tasks than passive prostheses. However, the effect of powered joints on bilateral biomechanics has not been widely explored for ambulation modes different than level ground and treadmill walking. In this study, we present the bilateral biomechanics of stair ascent and descent with a powered knee-ankle prosthesis compared to the biomechanical profiles of able-bodied subjects at different configurations of stair height between 102 mm and 178 mm. In addition, we include reference profiles from users with passive prostheses for the nominal stair height of 152 mm to place our findings in relation to the typical solution for individuals with transfemoral amputation (TFA). We report the biomechanical profiles of kinematics, kinetics, and power, together with temporal and waveform symmetry and distribution of mechanical energy across the joints. We found that an active prosthesis provides a substantial contribution to mechanical power during stair ascent and power absorption during stair descent and gait patterns like able-bodied subjects. The active prosthesis enables step-over-step gait in stair ascent. This translates into a lower mechanical energy requirement on the intact side, with a 57% reduction of energy at the knee and 26% at the hip with respect to the passive prosthesis. For stair descent, we found a 28% reduction in the negative work done by the intact ankle. These results reflect the benefit of active prostheses, allowing the users to complete tasks more efficiently than passive legs. However, in comparison to able-bodied biomechanics, the results still differ from the ideal patterns. We discuss the limitations that explain this difference and suggest future directions for the design of impedance controllers by taking inspiration from the biological modulation of the knee moment as a function of the stair height.


Assuntos
Membros Artificiais , Fenômenos Biomecânicos , Impedância Elétrica , Marcha , Humanos , Articulação do Joelho , Caminhada
2.
Medicine (Baltimore) ; 101(47): e32056, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36451475

RESUMO

Acetabular revision arthroplasty with major bone loss is one of the most difficult operations in hip arthroplasty, The graft augmentation prosthesis (GAP) has been designed particularly as an implant for revision acetabular reconstruction. We evaluated the use of GAP II acetabular cage in revision of acetabulum in total hip arthroplasty. From 2009 to 2014, we performed revision total hip arthroplasty in patients with acetabular defects by cage (GAP II) in patients referred to Milad and Erfan Hospitals, Tehran, Iran. We included all patients in class 3a and 3b of Paprosky bone loss classification and type III bone loss according to the system of the American Academy of Orthopedic Surgeons. We used SPSS software Ver 19 and descriptive tests, Chi square and independent t-test were used for analysis. There were 221 men (71.99%) and 86 women (28.01%) with an average age of 51.3 ±â€…21.7 years (range, 35-86 years). The Modified Harris Hip Score (MHHS) improved significantly at the last follow-up compared with the preoperative MHHS (P < .001). The mean MHHS was 40 (range, 29-44) preoperatively and 92 (range, 86-95) at the last follow-up. There were no major intraoperative complications during acetabular reconstruction. Our findings showed that using GAP II acetabular cage in the restoration of acetabulum in hip revision surgery is significantly desirable.


Assuntos
Artroplastia de Quadril , Membros Artificiais , Doenças Ósseas Metabólicas , Masculino , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Acetábulo/cirurgia , Reoperação , Irã (Geográfico)
3.
J Neuroeng Rehabil ; 19(1): 122, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369004

RESUMO

The concept of embodiment has gained widespread popularity within prosthetics research. Embodiment has been claimed to be an indicator of the efficacy of sensory feedback and control strategies. Moreover, it has even been claimed to be necessary for prosthesis acceptance, albeit unfoundedly. Despite the popularity of the term, an actual consensus on how prosthetic embodiment should be used in an experimental framework has yet to be reached. The lack of consensus is in part due to terminological ambiguity and the lack of an exact definition of prosthetic embodiment itself. In a review published parallel to this article, we summarized the definitions of embodiment used in prosthetics literature and concluded that treating prosthetic embodiment as a combination of ownership and agency allows for embodiment to be quantified, and thus useful in translational research. Here, we review the potential mechanisms that give rise to ownership and agency considering temporal, spatial, and anatomical constraints. We then use this to propose a multi-dimensional framework where prosthetic embodiment arises within a spectrum dependent on the integration of volition and multi-sensory information as demanded by the degree of interaction with the environment. This framework allows for the different experimental paradigms on sensory feedback and prosthetic control to be placed in a common perspective. By considering that embodiment lays along a spectrum tied to the interactions with the environment, one can conclude that the embodiment of prosthetic devices should be assessed while operating in environments as close to daily life as possible for it to become relevant.


Assuntos
Membros Artificiais , Pesquisa Translacional Biomédica , Humanos , Retroalimentação Sensorial
4.
J Neuroeng Rehabil ; 19(1): 119, 2022 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335345

RESUMO

BACKGROUND: The development of bionic legs has seen substantial improvements in the past years but people with lower-limb amputation still suffer from impairments in mobility (e.g., altered balance and gait control) due to significant limitations of the contemporary prostheses. Approaching the problem from a human-centered perspective by focusing on user-specific needs can allow identifying critical improvements that can increase the quality of life. While there are several reviews of user needs regarding upper limb prostheses, a comprehensive summary of such needs for those affected by lower limb loss does not exist. METHODS: We have conducted a systematic review of the literature to extract important needs of the users of lower-limb prostheses. The review included 56 articles in which a need (desire, wish) was reported explicitly by the recruited people with lower limb amputation (N = 8149). RESULTS: An exhaustive list of user needs was collected and subdivided into functional, psychological, cognitive, ergonomics, and other domain. Where appropriate, we have also briefly discussed the developments in prosthetic devices that are related to or could have an impact on those needs. In summary, the users would like to lead an independent life and reintegrate into society by coming back to work and participating in social and leisure activities. Efficient, versatile, and stable gait, but also support to other activities (e.g., sit to stand), contribute to safety and confidence, while appearance and comfort are important for the body image. However, the relation between specific needs, objective measures of performance, and overall satisfaction and quality of life is still an open question. CONCLUSIONS: Identifying user needs is a critical step for the development of new generation lower limb prostheses that aim to improve the quality of life of their users. However, this is not a simple task, as the needs interact with each other and depend on multiple factors (e.g., mobility level, age, gender), while evolving in time with the use of the device. Hence, novel assessment methods are required that can evaluate the impact of the system from a holistic perspective, capturing objective outcomes but also overall user experience and satisfaction in the relevant environment (daily life).


Assuntos
Amputados , Membros Artificiais , Humanos , Amputação , Amputados/psicologia , Qualidade de Vida , Extremidade Superior
5.
PLoS One ; 17(11): e0277917, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36399487

RESUMO

After a major upper limb amputation, the use of myoelectric prosthesis as assistive devices is possible. However, these prostheses remain quite difficult to control for grasping and manipulation of daily life objects. The aim of the present observational case study is to document the kinematics of grasping in a group of 10 below-elbow amputated patients fitted with a myoelectric prosthesis in order to describe and better understand their compensatory strategies. They performed a grasping to lift task toward 3 objects (a mug, a cylinder and a cone) placed at two distances within the reaching area in front of the patients. The kinematics of the trunk and upper-limb on the non-amputated and prosthetic sides were recorded with 3 electromagnetic Polhemus sensors placed on the hand, the forearm (or the corresponding site on the prosthesis) and the ipsilateral acromion. The 3D position of the elbow joint and the shoulder and elbow angles were calculated thanks to a preliminary calibration of the sensor position. We examined first the effect of side, distance and objects with non-parametric statistics. Prosthetic grasping was characterized by severe temporo-spatial impairments consistent with previous clinical or kinematic observations. The grasping phase was prolonged and the reaching and grasping components uncoupled. The 3D hand displacement was symmetrical in average, but with some differences according to the objects. Compensatory strategies involved the trunk and the proximal part of the upper-limb, as shown by a greater 3D displacement of the elbow for close target and a greater forward displacement of the acromion, particularly for far targets. The hand orientation at the time of grasping showed marked side differences with a more frontal azimuth, and a more "thumb-up" roll. The variation of hand orientation with the object on the prosthetic side, suggested that the lack of finger and wrist mobility imposed some adaptation of hand pose relative to the object. The detailed kinematic analysis allows more insight into the mechanisms of the compensatory strategies that could be due to both increased distal or proximal kinematic constraints. A better knowledge of those compensatory strategies is important for the prevention of musculoskeletal disorders and the development of innovative prosthetics.


Assuntos
Amputados , Membros Artificiais , Articulação do Cotovelo , Humanos , Fenômenos Biomecânicos , Cotovelo
6.
J Neural Eng ; 19(6)2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36317254

RESUMO

Objective.Advanced myoelectric hands enable users to select from multiple functional grasps. Current methods for controlling these hands are unintuitive and require frequent recalibration. This case study assessed the performance of tasks involving grasp selection, object interaction, and dynamic postural changes using intramuscular electrodes with regenerative peripheral nerve interfaces (RPNIs) and residual muscles.Approach.One female with unilateral transradial amputation participated in a series of experiments to compare the performance of grasp selection controllers with RPNIs and intramuscular control signals with controllers using surface electrodes. These experiments included a virtual grasp-matching task with and without a concurrent cognitive task and physical tasks with a prosthesis including standardized functional assessments and a functional assessment where the individual made a cup of coffee ('Coffee Task') that required grasp transitions.Main results.In the virtual environment, the participant was able to select between four functional grasps with higher accuracy using the RPNI controller (92.5%) compared to surface controllers (81.9%). With the concurrent cognitive task, performance of the virtual task was more consistent with RPNI controllers (reduced accuracy by 1.1%) compared to with surface controllers (4.8%). When RPNI signals were excluded from the controller with intramuscular electromyography (i.e. residual muscles only), grasp selection accuracy decreased by up to 24%. The participant completed the Coffee Task with 11.7% longer completion time with the surface controller than with the RPNI controller. She also completed the Coffee Task with 11 fewer transition errors out of a maximum of 25 total errors when using the RPNI controller compared to surface controller.Significance.The use of RPNI signals in concert with residual muscles and intramuscular electrodes can improve grasp selection accuracy in both virtual and physical environments. This approach yielded consistent performance without recalibration needs while reducing cognitive load associated with pattern recognition for myoelectric control (clinical trial registration number NCT03260400).


Assuntos
Membros Artificiais , Músculo Esquelético , Feminino , Humanos , Eletrodos , Eletromiografia/métodos , Mãos/fisiologia , Força da Mão , Músculo Esquelético/fisiologia , Nervos Periféricos/fisiologia
7.
Sci Robot ; 7(72): eabo3996, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36417500

RESUMO

Robotic leg prostheses promise to improve the mobility and quality of life of millions of individuals with lower-limb amputations by imitating the biomechanics of the missing biological leg. Unfortunately, existing powered prostheses are much heavier and bigger and have shorter battery life than conventional passive prostheses, severely limiting their clinical viability and utility in the daily life of amputees. Here, we present a robotic leg prosthesis that replicates the key biomechanical functions of the biological knee, ankle, and toe in the sagittal plane while matching the weight, size, and battery life of conventional microprocessor-controlled prostheses. The powered knee joint uses a unique torque-sensitive mechanism combining the benefits of elastic actuators with that of variable transmissions. A single actuator powers the ankle and toe joints through a compliant, underactuated mechanism. Because the biological toe dissipates energy while the biological ankle injects energy into the gait cycle, this underactuated system regenerates substantial mechanical energy and replicates the key biomechanical functions of the ankle/foot complex during walking. A compact prosthesis frame encloses all mechanical and electrical components for increased robustness and efficiency. Preclinical tests with three individuals with above-knee amputation show that the proposed robotic leg prosthesis allows for common ambulation activities with close to normative kinematics and kinetics. Using an optional passive mode, users can walk on level ground indefinitely without charging the battery, which has not been shown with any other powered or microprocessor-controlled prostheses. A prosthesis with these characteristics has the potential to improve real-world mobility in individuals with above-knee amputation.


Assuntos
Membros Artificiais , Procedimentos Cirúrgicos Robóticos , Humanos , Tornozelo , Fenômenos Biomecânicos , Qualidade de Vida , Desenho de Prótese , Articulação do Joelho/cirurgia , Articulação do Dedo do Pé
8.
Injury ; 53(12): 4114-4122, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36333155

RESUMO

AIM: Some amputees are unable to adequately ambulate using conventional socket prosthetics, osseointegrated prosthetics have been described as an alternative strategy in this patient group. This paper aims to assess the effect of osseointegrated prosthetics, commonly simply referred to as osseointegration, in transfemoral amputees on health-related quality of life and cost analysis. METHODS: Two centre analysis of patients receiving transcutaneous femoral osseointegration using The Osseointegration Group of Australia Osseointegration Prosthetic Limb (OGAP-OPL) implant. Retrospective health utility and cost analysis of prospectively collected patient reported health outcome data. Osseointegration cost was compared with the yearly cost of a poorly fitting conventional prosthetic determining cost/Quality Adjusted Life Year. RESULTS: Eighty amputees received osseointegration. Mean age was 39 years (range 20-57) and 66% were male (n = 53). The majority of subjects underwent unilateral (n = 62, 77.5%) rather than bilateral surgery (n = 18, 22.5%). Trauma was the most common indication (n = 59, 74%). Maximum follow up was 10.5-years. Mean preoperative EQ5D HUV in pooled data was 0.64 (SEM 0.025) increasing to 0.73 (0.036) at 5-years and 0.78 (0.051) at 6 years with continued improvement up to 10.5-years. In subgroup analysis those with a starting EQ5D HUV <0.60 reached a cost/QALY of <£30,000 at 5-years postoperatively and show statistically significant improvement in EQ5D HUV. The UK military experience was wholly positive with a mean starting EQ5D HUV of 0.48 (0.017) with significant (p < 0.05) improvement in EQ5D HUV at each time point and a resultant reducing cost/QALY at each time point being £28,616.89 at 5 years. CONCLUSION: There is both a quality of life and financial argument in favour of osseointegration in select patients with above transfemoral amputations. In those unable to mobilise satisfactorily with traditional prostheses and a pre-intervention score of <0.60, a consistent cost effectiveness and quality of life benefit can be seen. Such patients should be considered for osseointegration as these patients reap the maximum benefit and cost effectiveness of the device. This evidence lends strongly to the debate advocating the use of osseointegration through centrally funded resources, including the NHS.


Assuntos
Amputados , Membros Artificiais , Humanos , Masculino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Feminino , Osseointegração , Qualidade de Vida , Análise Custo-Benefício , Estudos Retrospectivos , Desenho de Prótese , Resultado do Tratamento , Amputação
9.
Sensors (Basel) ; 22(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36433483

RESUMO

Real-time gait event detection (GED) using inertial sensors is important for applications such as remote gait assessments, intelligent assistive devices including microprocessor-based prostheses or exoskeletons, and gait training systems. GED algorithms using acceleration and/or angular velocity signals achieve reasonable performance; however, most are not suited for real-time applications involving clinical populations walking in free-living environments. The aim of this study was to develop and evaluate a real-time rules-based GED algorithm with low latency and high accuracy and sensitivity across different walking states and participant groups. The algorithm was evaluated using gait data collected from seven able-bodied (AB) and seven lower-limb prosthesis user (LLPU) participants for three walking states (level-ground walking (LGW), ramp ascent (RA), ramp descent (RD)). The performance (sensitivity and temporal error) was compared to a validated motion capture system. The overall sensitivity was 98.87% for AB and 97.05% and 93.51% for LLPU intact and prosthetic sides, respectively, across all walking states (LGW, RA, RD). The overall temporal error (in milliseconds) for both FS and FO was 10 (0, 20) for AB and 10 (0, 25) and 10 (0, 20) for the LLPU intact and prosthetic sides, respectively, across all walking states. Finally, the overall error (as a percentage of gait cycle) was 0.96 (0, 1.92) for AB and 0.83 (0, 2.08) and 0.83 (0, 1.66) for the LLPU intact and prosthetic sides, respectively, across all walking states. Compared to other studies and algorithms, the herein-developed algorithm concurrently achieves high sensitivity and low temporal error with near real-time detection of gait in both typical and clinical populations walking over a variety of terrains.


Assuntos
Membros Artificiais , Humanos , Marcha , Caminhada , Algoritmos , Aceleração
10.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 36(11): 1374-1380, 2022 Nov 15.
Artigo em Chinês | MEDLINE | ID: mdl-36382455

RESUMO

Objective: To investigate the clinical application and effectiveness of three-dimensional (3D) printed customized prosthesis with preserved epiphysis and articular surface in the reconstruction of large bone defects in treatment of adolescent femoral malignant tumors. Methods: The clinical data of 10 adolescent patients with femoral primary malignant tumor who met the selection criteria and underwent limb salvage surgery with 3D printed customized prosthesis with preserved epiphysis and articular surface between January 2020 and October 2021 were retrospectively analyzed. There were 6 males and 4 females with an average age of 12.5 years ranging from 7 to 18 years. There were 8 cases of osteosarcoma and 2 cases of Ewing's sarcoma. Enneking stage was Ⅱb. The length of the lesions ranged from 76 to 240 mm, with an average of 138.0 mm. The length of osteotomy (i. e. length of customized prosthesis) ranged from 130 to 275 mm, with an average of 198.5 mm; the distance between distal osteotomy end and epiphyseal line ranged from 0 to 15 mm, with an average of 8.8 mm; the bone defect after osteotomy accounted for 37.36% to 79.02% of the total length of the lesion bone, with a mean of 49.43%. The operation time, intraoperative blood loss, complications, tumor outcome (refered to RESIST1.1 solid tumor efficacy evaluation criteria), and limb length discrepancy were recorded. The Musculoskeletal Cancer Society (MSTS) 93 score was used to evaluate the function at 6 months after operation, and visual analogue scale (VAS) score was used to evaluate the pain before and after operation. Results: The operation was successfully performed in all the 10 patients, and the postoperative pathological results were consistent with the preoperative pathological results. The operation time was 165-440 minutes, with an average of 263 minutes; and the intraoperative blood loss was 100-800 mL, with an average of 350 mL. All patients were followed up 7-26 months, with an average of 11.8 months. No tumor was found on the osteotomy surface; the customized prosthesis were firmly installed and closely matched with the retained articular surface. The tumor outcome of neoadjuvant chemotherapy was stable in 4 cases and partial remission in 6 cases. No local recurrence or distant metastasis was found in 9 cases after postoperative adjuvant chemotherapy; pulmonary metastasis was found in 1 case at 12 months after operation. Two patients had local incision fat liquefaction, superficial infection, and delayed healing at 14 days after operation; 1 patient had local bone absorption at the contact surface of the prosthesis, and the screw and prosthesis did not loosen at 7 months after operation; the other patients had good incision healing, with no infection, prosthesis loosening, fracture, or other complications. At 6 months after operation, the MSTS93 score was 19-28, with an average of 24.1; 8 cases were excellent and 2 cases were good. The VAS score was 0.9±1.0, which significantly improved when compared with before operation (5.9±1.0) ( t=23.717, P<0.001). The height of the patients increased by 1-12 cm, with an average of 4.6 cm. At last follow-up, 4 patients had limb length discrepancy, with a length difference of 1 cm in 2 cases and 2 cm in 2 cases. Conclusion: The application of 3D printed customized prosthesis in the resection and reconstruction of adolescents femoral primary malignant tumors can achieve the purpose of preserving epiphysis and articular surface, and obtain good effectiveness.


Assuntos
Membros Artificiais , Neoplasias Ósseas , Neoplasias Femorais , Masculino , Feminino , Adolescente , Humanos , Criança , Neoplasias Ósseas/cirurgia , Estudos Retrospectivos , Perda Sanguínea Cirúrgica , Resultado do Tratamento , Neoplasias Femorais/cirurgia , Epífises/cirurgia , Epífises/patologia , Salvamento de Membro
11.
Sensors (Basel) ; 22(20)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36298335

RESUMO

sEMG-based gesture recognition is useful for human-computer interactions, especially for technology supporting rehabilitation training and the control of electric prostheses. However, high variability in the sEMG signals of untrained users degrades the performance of gesture recognition algorithms. In this study, the hand posture recognition algorithm and radar plot-based visual feedback training were developed using multichannel sEMG sensors. Ten healthy adults and one bilateral forearm amputee participated by repeating twelve hand postures ten times. The visual feedback training was performed for two days and five days in healthy adults and a forearm amputee, respectively. Artificial neural network classifiers were trained with two types of feature vectors: a single feature vector and a combination of feature vectors. The classification accuracy of the forearm amputee increased significantly after three days of hand posture training. These results indicate that the visual feedback training efficiently improved the performance of sEMG-based hand posture recognition by reducing variability in the sEMG signal. Furthermore, a bilateral forearm amputee was able to participate in the rehabilitation training by using a radar plot, and the radar plot-based visual feedback training would help the amputees to control various electric prostheses.


Assuntos
Amputados , Membros Artificiais , Adulto , Humanos , Antebraço , Eletromiografia/métodos , Retroalimentação Sensorial , Mãos , Gestos , Algoritmos , Postura
12.
J Neural Eng ; 19(5)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36206722

RESUMO

Objective. Accurate decoding of surface electromyography (sEMG) is pivotal for muscle-to-machine-interfaces and their application e.g. rehabilitation therapy. sEMG signals have high inter-subject variability, due to various factors, including skin thickness, body fat percentage, and electrode placement. Deep learning algorithms require long training time and tend to overfit if only few samples are available. In this study, we aim to investigate methods to calibrate deep learning models to a new user when only a limited amount of training data is available.Approach. Two methods are commonly used in the literature, subject-specific modeling and transfer learning. In this study, we investigate the effectiveness of transfer learning using weight initialization for recalibration of two different pretrained deep learning models on new subjects data and compare their performance to subject-specific models. We evaluate two models on three publicly available databases (non invasive adaptive prosthetics database 2-4) and compare the performance of both calibration schemes in terms of accuracy, required training data, and calibration time.Main results. On average over all settings, our transfer learning approach improves 5%-points on the pretrained models without fine-tuning, and 12%-points on the subject-specific models, while being trained for 22% fewer epochs on average. Our results indicate that transfer learning enables faster learning on fewer training samples than user-specific models.Significance. To the best of our knowledge, this is the first comparison of subject-specific modeling and transfer learning. These approaches are ubiquitously used in the field of sEMG decoding. But the lack of comparative studies until now made it difficult for scientists to assess appropriate calibration schemes. Our results guide engineers evaluating similar use cases.


Assuntos
Algoritmos , Membros Artificiais , Humanos , Eletromiografia/métodos , Calibragem , Aprendizado de Máquina
13.
Exp Brain Res ; 240(11): 3011-3021, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36222884

RESUMO

Understanding the fundamental characteristics of prosthetic movement control is imperative in improving prosthesis design and training. This study quantified how using an upper limb prosthesis affected performance during goal-directed reaching tasks. Nine prosthesis users with unilateral transradial limb absence and nine healthy controls completed a series of goal-directed reaching movements with different goals: one spatial and three temporal with different goal frequencies. We quantified end-point accuracy, smoothness, and peak speed for the spatial task and temporal accuracy, horizontal distance, and speed for the temporal task. For the temporal task, we also used a goal-equivalent manifold (GEM) approach to decompose variability in movement distance and speed into those perpendicular and tangential to the GEM. Detrended fluctuation analysis (DFA) quantified the temporal persistence of each time series. For the spatial task, movements made with prostheses were less smooth, had larger end-point errors, and had slower peak speed compared to those with control limbs (p < 0.041). For the temporal task, movements made with prostheses and intact limbs of prosthesis users and control limbs were similar in distance and speed and had similar timing errors (p > 0.138). Timing errors, distance, speed, and GEM deviations were corrected similarly between prosthetic limbs and control limbs (p > 0.091). The mean and variability of distance, speed, and perpendicular deviations decreased with increased goal frequency (p < 0.001). Our results suggest that prosthesis users have a sufficient internal model to successfully complete ballistic movements but are unable to accurately complete movements requiring substantial feedback.


Assuntos
Membros Artificiais , Humanos , Objetivos , Extremidade Superior , Movimento , Fatores de Tempo
14.
Transl Vis Sci Technol ; 11(10): 34, 2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-36269183

RESUMO

Purpose: To determine the feasibility of a custom frame generation approach for nonsurgical management of severe blepharoptosis with the magnetic levator prosthesis (MLP). Methods: Participants (n = 8) with severe blepharoptosis (obscuring the visual axis) in one or both eyes who had previously been using a non-custom MLP had a craniofacial scan with a smartphone app to generate a custom MLP frame. A magnetic adhesive was attached to the affected eyelid. The custom MLP frame held a cylindrical magnet near the eyebrow above the affected eyelid, suspending it in the magnetic field while still allowing blinking. The spectacle magnet could be rotated manually, providing adjustable force via angular translation of the magnetic field. Fitting success and comfort were recorded, and interpalpebral fissure (IPF) was measured from video frames after 20 minutes in-office and one-week at-home use. Preference was documented, custom versus non-custom. Results: Overall, 88% of patients (7/8) were successfully fitted with a median 9/10 comfort (interquartile 7-10) and median ptosis improvement of 2.3 mm (1.3-5.0); P = 0.01). Exact binomial testing suggested, with 80% power, that the true population success rate was significantly greater than 45% (P = 0.05). Five participants took the custom MLP home for one week, with only one case of mild conjunctival redness which resolved without treatment. Highest to lowest force modulation resulted in a marginally significant median IPF adjustment of 1.5 mm (0.8 to 2.7; P = 0.06). All preferred the custom frame. Conclusions: The three-dimensional custom MLP frame generation approach using a smartphone app-based craniofacial scan is a feasible approach for clinical deployment of the MLP. Translational Relevance: First demonstration of customized frame generation for the MLP.


Assuntos
Membros Artificiais , Blefaroptose , Humanos , Blefaroptose/cirurgia , Músculos Oculomotores/diagnóstico por imagem , Músculos Oculomotores/cirurgia , Estudos de Viabilidade , Impressão Tridimensional , Fenômenos Magnéticos
15.
Phys Med Rehabil Clin N Am ; 33(4): 857-870, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36243476

RESUMO

Management of the post amputation wound and skin is an individualized and evolving process. Although no consensus recommendations are available, optimal wound healing occurs with a dressing that provides the appropriate level of moisture, and management of edema, and can assist in contracture prevention and limb protection. Management of comorbid conditions and complications that might impede healing, as well as nutritional optimization help promotes wound closure. A faster time to heal increases the opportunity and likelihood of prosthetic fitting and use, working toward improved functional independence.


Assuntos
Membros Artificiais , Amputação , Bandagens , Humanos , Cicatrização
16.
JAMA Netw Open ; 5(10): e2235074, 2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-36227599

RESUMO

Importance: Transcutaneous osseointegration post amputation (TOPA) creates a direct linkage between residual bone and an external prosthetic limb, providing superior mobility and quality of life compared with a socket prosthesis. The causes and potential risks of mortality after TOPA have not been investigated. Objective: To investigate the association between TOPA and mortality and assess the potential risk factors. Design, Setting, and Participants: This observational cohort study included all patients with amputation of a lower extremity who underwent TOPA between November 1, 2010, and October 31, 2021, at a specialty orthopedic practice and tertiary referral hospital in a major urban center. Patients lived on several continents and were followed up as long as 10 years. Exposures: Transcutaneous osseointegration post amputation, consisting of a permanent intramedullary implant passed transcutaneously through a stoma and connected to an external prosthetic limb. Main Outcomes and Measures: Death due to any cause. The hypotheses tested-that patient variables (sex, age, level of amputation, postosseointegration infection, and amputation etiology) may be associated with subsequent mortality-were formulated after initial data collection identifying which patients had died. Results: A total of 485 patients were included in the analysis (345 men [71.1%] and 140 women [28.9%]), with a mean (SD) age at osseointegration of 49.1 (14.6) years among living patients or 61.2 (12.4) years among patients who had died. Nineteen patients (3.9%) died a mean (SD) of 2.2 (1.7) years (range, 58 days to 5 years) after osseointegration, including 17 (3.5%) who died of causes unrelated to osseointegration (most commonly cardiac issues) and 2 (0.4%) who died of direct osseointegration-related complications (infectious complications), of which 1 (0.2%) was coclassified as a preexisting health problem exacerbated by osseointegration (myocardial infarction after subsequent surgery to manage infection). No deaths occurred intraoperatively or during inpatient recuperation or acute recovery after index osseointegration (eg, cardiopulmonary events). Kaplan-Meier survival analysis with log-rank comparison and Cox proportional hazards regression modeling identified increased age (hazard ratio, 1.06 [95% CI, 1.02-1.09]) and vascular (odds ratio [OR], 4.73 [95% CI, 1.35-16.56]) or infectious (OR, 3.87 [95% CI, 1.31-11.40]) amputation etiology as risk factors. Notable factors not associated with mortality risk included postosseointegration infection and male sex. Conclusions and Relevance: These findings suggest that patients who have undergone TOPA rarely die of problems associated with the procedure but instead usually die of unrelated causes.


Assuntos
Membros Artificiais , Osseointegração , Adulto , Amputação , Membros Artificiais/efeitos adversos , Feminino , Humanos , Extremidade Inferior/cirurgia , Masculino , Pessoa de Meia-Idade , Qualidade de Vida
17.
J Glob Health ; 12: 04083, 2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36259231

RESUMO

Background: Prosthetic service development and delivery rely on data describing population needs. These needs are context-specific, but most existing data come from high-income countries or small geographic areas, which are often not comparable. This study analysed routinely collected digital patient record data at multiple time points to provide insights into characteristics of people accessing Cambodian prosthetic services. Methods: We investigated trends in birth year, sex, year and reason for limb absence, and prosthesis type, over three decades. Then, we observed data from 2005 and 2019 indicating how the population actively accessing prosthetics services has changed. Results: Temporal trends in prosthetics service user demographics corresponded with events in Cambodia's socio-political history. The predominant historical reason for limb absence prior to 2000 was weapon trauma during and following conflict. Since 2000, this was replaced by non-communicable disease and road accidents. Transtibial remained the most prevalent amputation level but transfemoral amputation had higher incidence for people with limb loss from road accidents, and people with limb loss due to disease were older. These observations are important as both transfemoral and older-aged groups experience particular rehabilitation challenges compared to the young, transtibial group. Conclusions: The study shows how standardised, routinely collected data across multiple clinics within a country can be used to characterise prosthetics service user populations and shows significant changes over time. This indicates the need to track client characteristics and provides evidence for adapting services according to population dynamics and changes in patient need.


Assuntos
Amputados , Membros Artificiais , Humanos , Camboja , Amputados/reabilitação , Amputação
18.
Gait Posture ; 98: 240-247, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36195049

RESUMO

BACKGROUND: Despite prosthetic technology advancements, individuals with transfemoral amputation have compromised temporal-spatial gait parameters and high metabolic requirements for ambulation. It is unclear how adding mass at different locations on a transfemoral prosthesis might affect these outcomes. Research question Does walking with mass added at different locations on a transfemoral prosthesis affect temporal-spatial gait parameters and metabolic requirements compared to walking with no additional mass? METHODS: Fourteen participants with unilateral transfemoral amputations took part. A 1.8 kg mass was added to their prostheses in three locations: Knee, just proximal to the prosthetic knee; Shank, mid-shank on the prosthesis; or Ankle, just proximal to the prosthetic foot. Temporal-spatial gait parameters were collected as participants walked over a GAITRite® walkway and metabolic data were collected during treadmill walking for each of these conditions and with no mass added, the None condition. Separate linear mixed effects models were created and post-hoc tests to compare with the control condition of None were performed with a significance level of 0.05. RESULTS: Overground self-selected walking speed for Ankle was significantly slower than for None (p < 0.05) (None: 1.16 ± 0.24; Knee: 1.15 ± 0.19; Shank: 1.14 ± 0.24; Ankle 0.99 ± 0.20 m/s). Compared to None, Ankle showed significantly increased oxygen consumption during treadmill walking (p < 0.05) (None: 13.82 ± 2.98; Knee: 13.83 ± 2.82; Shank: 14.30 ± 2.89; Ankle 14.56 ± 2.99 ml O2/kg/min). Other metabolic outcomes (power, cost of transport, oxygen cost) showed similar trends. Knee and Shank did not have significant negative effects on any metabolic or temporal-spatial parameters, as compared to None (p > 0.05). Significance Results suggest that additional mass located mid-shank or further proximal on a transfemoral prosthesis may not have negative temporal-spatial or metabolic consequences. Clinicians, researchers, and designers may be able to utilize heavier components, as long as the center of mass is not further distal than mid-shank, without adversely affecting gait parameters or metabolic requirements.


Assuntos
Amputados , Membros Artificiais , Humanos , Fenômenos Biomecânicos , Marcha , Amputação , Velocidade de Caminhada , Caminhada , Desenho de Prótese
19.
Sci Rep ; 12(1): 16696, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36202893

RESUMO

A non-optimal prosthesis integration into an amputee's body schema suggests some important functional and health consequences after lower limb amputation. These include low perception of a prosthesis as a part of the body, experiencing it as heavier than the natural limb, and cognitively exhausting use for users. Invasive approaches, exploiting the surgical implantation of electrodes in residual nerves, improved prosthesis integration by restoring natural and somatotopic sensory feedback in transfemoral amputees. A non-invasive alternative that avoids surgery would reduce costs and shorten certification time, significantly increasing the adoption of such systems. To explore this possibility, we compared results from a non-invasive, electro-cutaneous stimulation system to outcomes observed with the use of implants in above the knee amputees. This non-invasive solution was tested in transfemoral amputees through evaluation of their ability to perceive and recognize touch intensity and locations, or movements of a prosthesis, and its cognitive integration (through dual task performance and perceived prosthesis weight). While this managed to evoke the perception of different locations on the artificial foot, and closures of the leg, it was less performant than invasive solutions. Non-invasive stimulation induced similar improvements in dual motor and cognitive tasks compared to neural feedback. On the other hand, results demonstrate that remapped, evoked sensations are less informative and intuitive than the neural evoked somatotopic sensations. The device therefore fails to improve prosthesis embodiment together with its associated weight perception. This preliminary evaluation meaningfully highlights the drawbacks of non-invasive systems, but also demonstrates benefits when performing multiple tasks at once. Importantly, the improved dual task performance is consistent with invasive devices, taking steps towards the expedited development of a certified device for widespread use.


Assuntos
Membros Artificiais , Retroalimentação Sensorial , Amputados , Cognição , Retroalimentação , Humanos , Neuroestimuladores Implantáveis
20.
Sci Rep ; 12(1): 17501, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36261465

RESUMO

Lower-limb amputation imposes a health burden on amputees; thus, gait assessments are required prophylactically and clinically, particularly for individuals with unilateral transfemoral amputation (UTFA). The centre of pressure (COP) during walking is one of the most useful parameters for evaluating gait. Although superimposed COP trajectories reflect the gait characteristics of individuals with neurological disorders, the quantitative characteristics based on the COP trajectories of individuals with UTFA remain unclear. Thus, these COP trajectories were investigated across a range of walking speeds in this study. The COP trajectories were recorded on a split-belt force-instrumented treadmill at eight walking speeds. Asymmetry and variability parameters were compared based on the COP trajectories of 25 individuals with UTFA and 25 able-bodied controls. The COP trajectories of the individuals with UTFA were significantly larger in lateral asymmetry and variability but did not show significant differences in anterior-posterior variability compared with those of the able-bodied controls. Further, the individuals with UTFA demonstrated larger lateral asymmetry at lower speeds. These results suggest that (1) individuals with UTFA adopt orientation-specific balance control strategies during gait and (2) individuals with UTFA could also be exposed to a higher risk of falling at lower walk speeds.


Assuntos
Amputados , Membros Artificiais , Humanos , Amputação/métodos , Caminhada , Marcha , Fenômenos Biomecânicos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...