Upper-limb Amputees Research Articles

Nonfinancial Barriers to Prosthetic Use Following Upper-Limb Amputation: A Prospective Observational Study in India

ABSTRACT Introduction Upper-limb traumatic amputation is a common and poorly managed situation. Despite the huge burden, no study from the developing countries has evaluated rates of prosthesis acceptance and reasons for rejecting prostheses. Materials and Methods This was a longitudinal prospective observational study with a consecutive sampling technique. Participants were assessed after a period of 6 months of isolated upper-limb amputation. Patients were evaluated for reasons of nonfitment of upper-limb prosthesis despite their willingness to be fitted with an appropriate prosthesis. We conducted semistructured interviews to identify the potential hindrances. Results A total of 44 patients were recruited, out of which 38 did not get the prosthesis. A total of 57.8% reported a nonfinancial reason for prosthesis nonfitment. Nonfinancial is further classified into medical and nonmedical categories as per verbatim remarks by the patient. Among the nonmedical reasons, the most common reason was apprehension toward the use of the prosthesis, followed by satisfaction without the prosthesis and the weight of the prosthesis. In terms of medical reasons, the most common reason was persistent phantom limb pain, followed by residual limb infection. Conclusions Identification of “potentially correctable” hindrances to prosthesis acceptance is an essential step in the rehabilitation of persons with limb loss. All efforts should be made toward these hindrances so that persons with limb difference can be better rehabilitated. Clinical Relevance Given that some persons with limb difference need to be fitted with prostheses for optimal rehabilitation and to return as an able contributor to society, the identification of hindrances to prosthesis fitting is imperative to make further inroads toward improving prosthesis acceptance rate.

THE DESIGN OF A ROTATING MODULAR UPPER LIMB PROSTHETIC WRIST UNIT

This design study investigates a Prosthetic Wrist Unit for upper limb amputations using the Design Thinking methodology. It covers Problem Definition, Information Gathering, Concept Generation and Evaluation, Product Architecture, Configuration Design, Parametric Design, Detail Design, and Production. The study aims to create a small prosthetic wrist unit (50 mm diameter, 50 mm length, less than 125 gr), provides 360° rotation, connects easily with prosthetic hands, enables electric and data transfer, and is controllable via EMG sensors. This research contributes to prosthetic product design, enhancing the quality of life for amputees.

SoftBoMI: a non-invasive wearable body-machine interface for mapping movement of shoulder to commands

Objective.Customized human-machine interfaces for controlling assistive devices are vital in improving the self-help ability of upper limb amputees and tetraplegic patients. Given that most of them possess residual shoulder mobility, using it to generate commands to operate assistive devices can serve as a complementary approach to brain-computer interfaces.Approach.We propose a hybrid body-machine interface prototype that integrates soft sensors and an inertial measurement unit. This study introduces both a rule-based data decoding method and a user intent inference-based decoding method to map human shoulder movements into continuous commands. Additionally, by incorporating prior knowledge of the user's operational performance into a shared autonomy framework, we implement an adaptive switching command mapping approach. This approach enables seamless transitions between the two decoding methods, enhancing their adaptability across different tasks.Main results.The proposed method has been validated on individuals with cervical spinal cord injury, bilateral arm amputation, and healthy subjects through a series of center-out target reaching tasks and a virtual powered wheelchair driving task. The experimental results show that using both the soft sensors and the gyroscope exhibits the most well-rounded performance in intent inference. Additionally, the rule-based method demonstrates better dynamic performance for wheelchair operation, while the intent inference method is more accurate but has higher latency. Adaptive switching decoding methods offer the best adaptability by seamlessly transitioning between decoding methods for different tasks. Furthermore, we discussed the differences and characteristics among the various types of participants in the experiment.Significance.The proposed method has the potential to be integrated into clothing, enabling non-invasive interaction with assistive devices in daily life, and could serve as a tool for rehabilitation assessment in the future.

Training in the Use of Myoelectric Prostheses Through the Combined Application of Immersive Virtual Reality, Cross-education, and Mirror Therapy

ABSTRACT Introduction During the rehabilitation process (RHB) of the patient with traumatic upper-limb amputation, the use of immersive virtual reality (IVR) facilitates the incorporation of the prosthesis into the body schema. This reinforces and enhances sensorimotor and cognitive stimulation to improve motor learning and motor patterns, while normalizing global gestures. Objectives The aims of this study were to implement retraining of gestural acquisition and prosthetic control in patients with upper-limb injuries and amputations through IVR, and to then incorporate this in the normalization of functional patterns in activities of daily living (ADLs) with the work of “cross-education” as well as the therapy of observation of actions—mirror therapy to enhance the joint effect of the approach with IVR. Methods Standard sessions were established for transradial and transhumeral trauma patients with upper-limb amputation and traumatic injuries within the rehabilitation treatment. During the sessions, games and virtual environment were used. The software ran in desktop mode using a “Leap Motion” or for immersive versions of 3D glasses (Oculus Rift S). Results The application of IVR in combination with conventional treatment obtained significant benefits for functionality. These included learning correct motor execution as well as motivational and emotional state with distal traumatic injuries and upper-limb amputations with or without myoelectric prosthesis, obtaining 5.6 on average on the GROC (global rating of change) scale. Conclusions Immersive virtual reality shows benefit for the normalization of motor learning of functional patterns in DLA and on the emotional, motivational level of the patient. Clinical Relevance The integrated combination of cross-education, mirror therapy, and immersive virtual reality may represent greater acquisition of motor patterns in the prosthetic training of patients with upper-limb amputation.

Osseointegration: A new approach to improve functional performance of prostheses – a systematic review of the literature

Background: Individuals with amputations experience functional limitations in their daily activities, depending on the level of their injuries. They often encounter problems with socket-based prostheses. Osseointegration is a new method in prosthetic rehabilitation that aims to enhance the performance of amputees and reduce the issues associated with current prostheses. The objective of this review was to assess the advantages and disadvantages of this novel approach in the rehabilitation of amputees. Method: A search was conducted in various databases, including Google Scholar, PubMed, ISI Web of Knowledge, Embase, and Scopus. The search terms used were “osseointegration,” “prosthesis,” and “amputation.” The quality of the studies was evaluated using the Down and Black tool. Results: The search using the aforementioned keywords yielded 18 papers. Out of these, 10 papers focused on the use of osseointegration for lower limb amputations, while 5 papers focused on upper limb amputations. Additionally, 3 papers examined the occurrence of stump infections associated with this method. The quality of the studies ranged from 15 to 20. Conclusion: Based on the available literature, osseointegration addresses some of the challenges associated with socket-based prostheses. Furthermore, it improves the performance of prostheses. However, there are several issues with this method, including high costs, stump infections, and the need for extensive expertise to insert the implant. Further large-scale studies are necessary to determine the various limitations and advantages of this approach for different levels of amputations.

Multiplexed Piezoelectric Electronic Skin with Haptic Feedback for Upper Limb Prosthesis

AbstractUpper limb amputation severely impairs tactile perception, limiting daily activities. Developing a near‐natural replacement with prosthetic devices requires improving user sensory experiences during object interactions. The ideal upper limb prosthesis should provide real‐time sensory feedback, mirroring natural experiences. Current prostheses struggle with providing adequate tactile feedback due to sensory limitations. Inspired by the sensory properties of skin, we present a micro‐fabricated, multiplexed electronic skin (e‐skin) with actuators for sensory feedback in upper limb amputation. The piezoelectric‐capacitive sensor array detects static pressure, temperature, vibration, and texture, with integrated actuators stimulating the skin to provide real‐time feedback. The sensors integrate with actuators via readout electronics, making the system standalone and easy to use. The flexible, compact sensor array design (two pixels within a 1 cm² footprint) detects a wide range of pressure (0.5–10 kPa), temperature (22–60 °C), vibration (35–100 Hz), and texture (2.5–45 Hz), suitable for daily use. The e‐skin, attached to a prosthetic finger, is tested for feasibility on human volunteers with wrist‐mounted actuators. Statistics are used to quantitatively assess system performance. The integration of multiplexed sensors and actuators enhances tactile feedback, improving the quality of life for people with upper limb amputations.

What Are the Factors Associated With Revision Surgery on the Residual Limb and Functional Results in Patients With Posttraumatic Lower Limb Amputations?

Lower limb amputations performed after trauma are associated with a high risk of revision surgery. While the factors influencing revision surgery in the upper limbs have been studied, no studies have analyzed these factors in the lower limbs. Existing explanations for these revision surgeries are unclear, often leaving patients uninformed. Surgeons also lack the tools to explain the factors that influence repeat operations to patients. Therefore, the aim of this study was to provide surgeons with some answers so they can inform their patients undergoing posttraumatic lower limb amputation, whether military or civilian. (1) What was the survivorship of the initial amputation free from any revision surgery? (2) What patient- and injury-related factors were associated with revision amputation? (3) Do these factors influence functional outcomes in these patients? A single-center, retrospective study was conducted between January 2010 and February 2020 on patients who had undergone traumatic lower limb amputation. Between January 2010 and February 2020, 322 patients underwent amputation or were followed up at Percy Military University Hospital. Thirty-one patients had undergone amputation at another center, 178 had undergone amputation for nontraumatic reasons, and 27 patients had only upper limb amputations. Of those remaining, 1 died before 6 months, and 6% (5 of 86) were not fitted with a prosthesis, leaving 99% (85 of 86) for survivorship free from revision analysis and 93% (80 of 86) for functional endpoints analysis in this retrospective study at a median of 6.5 years (IQR 5 to 9) following the index amputation. The median age at the time of amputation was 31 years (IQR 26 to 52), 85% (72 of 85) of patients were men, and 31% (26 of 85) were military personnel. Revision surgery was defined as surgery performed at or after 6 months to ensure that the residual limb was healed and fitted with a prosthesis. Revision procedures performed before 6 months (median 2 [IQR 0 to 7]) were considered as part of the initial residual limb formation surgery. We performed Kaplan-Meier survivorship analysis for the time free from revision amputation from 6 months after amputation. We considered the competitive risk of death using a Fine-Gray model by an ascending stepwise procedure. To answer our third research question, we performed a chart review and assessed patients' use of prostheses and assistive devices and the percentage of patients who returned to work. An ordinal logistic regression was used to analyze the factors influencing functional outcome using an ascending stepwise procedure. A total of 85 patients (94 limbs) were included, of whom 25 (27 limbs) underwent a revision surgery on the residual limb > 6 months after amputation. Kaplan-Meier survival estimates indicated that 5 years after the initial amputation 64% (95% confidence interval 53% to 77%) of the patients remained free from revision surgery on their residual limb. Factors associated with increased odds of revision amputation were smoking (subdistribution HR 2.6 [95% CI 1.2 to 5.8]; p = 0.02) and an age of > 50 years (subdistribution HR 0.3 [95% CI 0.1 to 0.8]; p = 0.01). Ninety-four percent (80 of 85) of patients were fitted with prostheses, and 40% (32 of 80) of patients used material or human assistance for simple activities of daily living. Seventy-one percent of patients (57 of 80) had returned to work. Ordinal logistic regression revealed an association between preinjury sports activity and the absence of need for assistance in daily activities (OR 9 [95% CI 2.9 to 31.8]; p < 0.001). Smoking appeared to be an associated risk factor for residual limb revision surgery in posttraumatic lower limb amputations and is potentially modifiable. Being at least 50 years of age seemed to be associated with a lower incidence of revision surgery, which is probably linked to lower functional demands made on limbs beyond this age. Our study showed a remarkable rate of fitting with a prosthetic device, with an improved functional result if the patient was athletic before the trauma. These results provide more precise information on the care pathway to be considered for each patient. A study with a much larger sample would make it possible to assess the risk factors for the occurrence of each complication involving revision surgery. Level III, therapeutic study.

Restoration of grasping in an upper limb amputee using the myokinetic prosthesis with implanted magnets.

The loss of a hand disrupts the sophisticated neural pathways between the brain and the hand, severely affecting the level of independence of the patient and the ability to carry out daily work and social activities. Recent years have witnessed a rapid evolution of surgical techniques and technologies aimed at restoring dexterous motor functions akin to those of the human hand through bionic solutions, mainly relying on probing of electrical signals from the residual nerves and muscles. Here, we report the clinical implementation of an interface aimed at achieving this goal by exploiting muscle deformation, sensed through passive magnetic implants: the myokinetic interface. One participant with a transradial amputation received an implantation of six permanent magnets in three muscles of the residual limb. A truly self-contained myokinetic prosthetic arm embedding all hardware components and the battery within the prosthetic socket was developed. By retrieving muscle deformation caused by voluntary contraction through magnet localization, we were able to control in real time a dexterous robotic hand following both a direct control strategy and a pattern recognition approach. In just 6 weeks, the participant successfully completed a series of functional tests, achieving scores similar to those achieved when using myoelectric controllers, a standard-of-care solution, with comparable physical and mental workloads. This experience raised conceptual and technical limits of the interface, which nevertheless pave the way for further investigations in a partially unexplored field. This study also demonstrates a viable possibility for intuitively interfacing humans with robotic technologies.

Increased Risk of Fracture after Traumatic Amputation: A Nationwide Retrospective Cohort Study.

The physiological changes and alterations in gait following amputation may increase the risk of fractures. However, there is insufficient research on fracture risk in amputees. Therefore, this study intended to analyze whether the risk of new fractures increases after traumatic amputations. This population-based, retrospective cohort study used data from the Korean National Health Insurance System database. The study included 19,586 participants who had undergone an amputation and 76,645 matched controls. The incidence of any fracture and site-specific fractures (vertebral, hip, and others) according to amputation site(s) and severity of disability due to amputation were evaluated using Cox proportional hazard regression analysis. During the mean follow-up of 4.2 years, amputees had a higher incidence rate (IR) of any fracture (adjusted HR [aHR] 1.47, 95% CI 1.36-1.60), vertebral fracture (aHR 1.63, 95% CI 1.44-1.85), hip fracture (aHR 1.85, 95% CI 1.39-2.46), and other fracture (aHR 1.34, 95% CI 1.20-1.49) compared to that of controls. In the presence of disability, the risks were further increased and were highest among amputees with severe disabilities. All fracture risks were higher in amputees than they were in controls, regardless of lower limb or upper limb amputation. This cohort study demonstrated that traumatic amputees experienced higher incidence of all fractures than did individuals without amputations, and this risk increases with severity of disability. This finding underscores the importance of early screening and lifestyle interventions to address fracture risk in traumatic amputees.

Single-Stage Press-Fit Osseointegration of the Radius and Ulna for Rehabilitation After Trans-Forearm Amputation.

Upper limb (UL) amputation is disabling. ULs are necessary for many domains of life1, and few effective motor and sensory replacements are accessible2. Approximately 41,000 people in the United States have UL amputation proximal to the fingers3, two-thirds of (all) traumatic amputations are UL4, and 80% of UL amputations are performed for trauma-related etiologies5. Socket prosthesis (SP) abandonment remains high because of the lack of sensation, limited prosthesis control, perceived weight, and difficulty comfortably wearing the SP6. Transcutaneous osseointegration7,8 surgically inserts a bone-anchored implant, passed through a transcutaneous portal to attach a terminal device, improving amputee rehabilitation by reducing perceived weight, conferring osseoperception9, and increasing wear time10. Without the socket, all residual skin and musculature remain available for transcutaneous myoelectrodes. The present article describes single-stage radius and ulna press-fit osseointegration (PFOI) after trans-forearm amputation. This technique resembles a lower-extremity PFOI11,12. Importantly, at-risk nerves and vessels are different, and implant impaction must be gentler as a result. The surgery is indicated for patients who are dissatisfied with SP rehabilitation or declining alternative rehabilitative options, and who are motivated and enabled to procure, train with, and utilize a forearm prosthesis. An engaged prosthetist is critical. Surgical steps are exposure, bone-end and canal preparation, first implant insertion (in the operative video shown, in the radius), purse-string muscle closure, confirmation that radius-ulna motion remains, performing the prior steps for the other bone (in the video, the ulna), and closure (including potential nerve reconstruction, soft-tissue contouring, and portal creation). Although the patient in the operative video did not require nerve procedures to address pain or to create targets for transcutaneous myoelectrodes, targeted muscle reinnervation or a regenerative peripheral nerve interface procedure could be performed following exposure. Alternatives include socket modification, bone lengthening and/or soft-tissue contouring13, Krukenberg-type reconstructions14, or accepting the situation. An alternative implant is a screw-type osseointegration implant. Our preference for press-fit implants is based on considerations such as our practice's 12-year history of >1,000 PFOI surgeries; that the screw-type implant requires sufficient cortical thickness for the threads15, which is compromised in some patients; the lower cost per implant; that the procedure is performed in 1 instead of 2 surgical episodes15,16; and the documented suitability of press-fit implants for patients with challenging anatomy or comorbidities17-19. PFOI can be provided for amputees having difficulty with socket wear. PFOI usually provides superior prosthesis stability, which can confer better prosthesis control versus nonoperative and other operative options in patients expressing dissatisfaction for reasons such as those mentioned above, or for poor fit, compromised energy transfer, skin pinching, compression, and abrasions. For patients who want myoelectric control of their prosthesis but who are unable because the optimal myoelectric location is obstructed by the socket, osseointegration may provide access for the electrodes by eliminating the socket. Only 3 trans-forearm osseointegration20-22 publications totaling 10 limbs could be identified, limiting the ability to determine generalizable outcomes. Osseointegrated prostheses, being skeletally anchored, feel lighter to patients than SPs, which should confer better outcomes. In 1 patient, multiple implant fractures and infection prompted additional surgeries. Periprosthetic bone fractures and non-infectious loosening have not been documented for UL osseointegration. Osseointegration eliminates the socket, relieving socket-based pain. However, neurogenic pain relief requires specific nerve procedures.Osseointegration provides a prosthesis connection. Nerve- or muscle-based prosthesis control requires separate, potentially integrated planning.Osseointegrated prostheses confer osseoperception (i.e., mechanical force transmission), not "normal" skin-mediated afferent sensation (i.e., light touch, temperature, pain) or native proprioception.Prostheses must be individualized to the patient's elbow flexion and radioulnar rotation. An attentive prosthetist must be ensured preoperatively.Achieving the demonstrated outcomes requires more therapy and retraining than walking with an osseointegrated lower-extremity prosthesis. Patients must expect at least several months of spending multiple hours daily engaging in self-directed rehabilitation.Prosthesis utilization decision aids23 may minimize non-beneficial surgeries. UL = upper limbSP = socket prosthesisPFOI = press-fit osseointegrationperi-pros fx = periprosthetic fractureMRI = magnetic resonance imagingCT = computed tomography.

Prosthesis Usage and Functional Status in Upper Limb Amputees: A Prospective Cross-Sectional Study.

Introduction Amputation poses significant challenges encompassing psychological, physical, and socio-economic dimensions, impacting individuals and society at large. In India, a substantial portion of the population faces loco-motor disabilities, with amputees forming a notable segment. Prosthetic rehabilitation plays a crucial role in mitigating the consequences of limb loss, aiming to restore autonomy post-amputation. Methods A prospective cross-sectional observational study was conducted over 18 months, from November 2018 to May 2020, involving unilateral upper limb amputees (ULAs) aged over 18 years. A consecutive cohort of 33 patients, predominantly male (30 males and three females), with a mean age of 43 ± 12 years (median: 43 years; range: 20-67 years), was prospectively enrolled in the study. Participants had completed at least one month of post-prosthetic fitment and were actively attending outpatient or prosthetic checkout clinics. The study utilized the Manipal Prosthetic Rehabilitation Success (PRS) score and the Orthotics and Prosthetics User Survey Upper Extremity Functional Status (OPUS UEFS) score to assess prosthesis usage and functional status. Statistical analyses included descriptive statistics, Chi-square tests, Mann-Whitney U tests, Kruskal-Wallis tests, and multivariate logistic regression analysis. Results The study revealed insights into upper limb prosthesis usage in India, highlighting factors influencing the success and challenges faced by ULAs. Associations were found between the success of prosthesis usage and several factors: occupation type (p=0.012), the side of amputation involving non-dominant limbs (p=0.033), comfort level (p=0.002), and prosthesis weight (p=0.029). Comfort level emerged as a primary predictor of usage success. The OPUS UEFS scores indicated varying levels of satisfaction and usage patterns among participants, with some utilizing prostheses for specific tasks while others for broader activities. Comfort level demonstrated a statistically significant difference in OPUS UEFS scores, favoring comfortable prostheses (p=0.020). Additionally, the mean OPUS UEFS score for patients with satisfactory or good prosthesis use was 53 ± 11 (median: 55; range: 22-64), compared to 45 ± 13 (median: 43; range: 18 - 64) in those with poor prosthesis use, with the difference nearing statistical significance (p=0.058). Conclusion The study sheds light on the landscape of upper limb prosthesis usage in India, emphasizing the need for tailored interventions based on individual needs and cultural contexts. The findings underscore the importance of comfort, side of amputation involving non-dominant limbs, occupation type, and prosthesis weight in determining the success of prosthesis usage. Opportunities exist to enhance upper limb prosthetic care in India by addressing cultural nuances and refining assessment tools to better suit the Indian population.

Multichannel Sensorimotor Integration with a Dexterous Artificial Hand

People use their hands for intricate tasks like playing musical instruments, employing myriad touch sensations to inform motor control. In contrast, current prosthetic hands lack comprehensive haptic feedback and exhibit rudimentary multitasking functionality. Limited research has explored the potential of upper limb amputees to feel, perceive, and respond to multiple channels of simultaneously activated haptic feedback to concurrently control the individual fingers of dexterous prosthetic hands. This study introduces a novel control architecture for three amputees and nine additional subjects to concurrently control individual fingers of an artificial hand using two channels of context-specific haptic feedback. Artificial neural networks (ANNs) recognize subjects’ electromyogram (EMG) patterns governing the artificial hand controller. ANNs also classify the directions objects slip across tactile sensors on the robotic fingertips, which are encoded via the vibration frequency of wearable vibrotactile actuators. Subjects implement control strategies with each finger simultaneously to prevent or permit slip as desired, achieving a 94.49% ± 8.79% overall success rate. Although no statistically significant difference exists between amputees’ and non-amputees’ success rates, amputees require more time to respond to simultaneous haptic feedback signals, suggesting a higher cognitive load. Nevertheless, amputees can accurately interpret multiple channels of nuanced haptic feedback to concurrently control individual robotic fingers, addressing the challenge of multitasking with dexterous prosthetic hands.

PCR219 Disparities in Physical Function in Upper Limb Amputation: Influence of Race and Veteran Status

PCR219 Disparities in Physical Function in Upper Limb Amputation: Influence of Race and Veteran Status

Quality of life, functioning and participation of adult patients with an amputation following complex regional pain syndrome I or brachial plexus injury: a scoping review protocol

IntroductionThis planned scoping review aims to provide insight into current literature regarding perceived quality of life (QoL), functioning and participation of patients with upper limb amputations (ULA) because of therapy-resistant...

Development of Agricultural Assistive Device and Phage Locking Algorithm to secure A Rural Labor Convenience System for Upper-Limb Amputee

Development of Agricultural Assistive Device and Phage Locking Algorithm to secure A Rural Labor Convenience System for Upper-Limb Amputee

Necrotizing soft-tissue infection of the upper limb: A single-center study of 24 cases

ObjectivesNecrotizing soft-tissue infection and necrotizing fasciitis of the upper limb are infrequent. Studies are rare, and often include other anatomical regions. The specificities and particularities of this pathology are not well known. The aim of this study was to report diagnosis and treatment aspects. MethodsA retrospective study was conducted over 10 years on every patient treated for necrotizing fasciitis of the upper limb with clinical, bacteriological and histological confirmation. One hundred ninety-eight items were extracted for each patient concerning clinical, biological, radiological and therapeutic data. ResultsDuring 10 years, 24 patients were diagnosed with necrotizing fasciitis of the upper limb: 18 males, 6 females; mean age, 59.9 years; mean body mass index, 25. Local erythema, pain and fever were the most frequent symptoms. Skin necrosis was present in fewer than 40% of patients.Sixteen cases (66.6%) had prior skin lesions and/or an entry point on the limb. Ten had non-steroidal anti-inflammatory drug prescription before acute symptom onset (42%), requiring intensive care unit admission.Treatment comprised surgical resection, resuscitative measures, antibiotic therapy and reconstructive surgery. Seven patients (30.4%) had 1 session of cutaneous excision, and the others had more than 2. Microbiological analysis found mono-microbial beta-hemolytic group A streptococci (BHGAS) infection in 14 patients (58.4%). Antibiotics were prescribed in 91% of cases before surgery, and in 100% after. The most frequently prescribed substance was clindamycin (18 patients, 75%).Ten patients (42%) stayed in the intensive care unit during treatment.Seventeen patients (70.8%) had thin skin graft reconstruction, including 50% with dermal substitute. Five patients (20.8%) had partial upper limb amputation. Two patients (8.3%) died in the 30 days following diagnosis. ConclusionsThe death rate in necrotizing fasciitis of the upper limb was rather low but the amputation rate was higher than in other locations.This study shows the specific clinical, biological and treatment features of this rare but serious pathology of the upper limb.

Vision-aided grasp classification: design and evaluation of compact CNN for prosthetic hands

Powered prosthetic hands capable of executing various grasp patterns are highly sought-after solutions for upper limb amputees. A crucial requirement for such prosthetic hands is the accurate identification of the intended grasp pattern and subsequent activation of the prosthetic digits accordingly. Vision-based grasp classification techniques offer improved coordination between amputees and prosthetic hands without physical contact. Deep learning methods, particularly Convolutional Neural Networks (CNNs), are utilized to process visual information for classification. The key challenge lies in developing a model that can effectively generalize across various object shapes and accurately classify grasp classes. To address this, a compact CNN model named GraspCNet is proposed, specifically designed for grasp classification in prosthetic hands. The use of separable convolutions reduces the computational burden, making it potentially suitable for real-time applications on embedded systems. The GraspCNet model is designed to learn and generalize from object shapes, allowing it to effectively classify unseen objects beyond those included in the training dataset. The proposed model was trained and tested using various standard object data sets. A cross-validation strategy has been adopted to perform better in seen and unseen object class scenarios. The average accuracy achieved was 82.22% and 75.48% in the case of seen, and unseen object classes respectively. In computer-based real-time experiments, the GraspCNet model achieved an accuracy of 69%. A comparative analysis with state-of-the-art techniques revealed that the proposed GraspCNet model outperformed most benchmark techniques and demonstrated comparable performance with the DcnnGrasp method. The compact nature of the GraspCNet model suggests its potential for integration with other sensing modalities in prosthetic hands.

Cosmetic gloves from natural rubber latex for upper limb prostheses: Preparation and physicochemical, mechanical and biological characterization

Upper limb amputations are frequently the result of traumatic events, often associated with car accidents or incidents involving industrial machinery. The development of prosthetic technologies is essential to provide physical assistance to amputees and offer psychological support. In such circumstances, cosmetic gloves can be utilized to improve personal and social comfort by enhancing visual characteristics similar to those of a biological hand. In this work, we developed formulations based on natural rubber latex (NRL) with antibacterial properties by the incorporation of an additive consisting of zinc oxide coated with silver nanoparticles to manufacture cosmetic gloves designed for upper limb prostheses. The dispersion efficiency of the additive was investigated by microscopic techniques. Tensile and tear strength tests, Shore A hardness measurements, swelling indices, hydrophobicity and inhibition of bacterial growth were also conducted to ascertain the suitability and adaptability of the developed material for integration into the daily activities of patients. Moreover, processing parameters for the immersion molding production of cosmetic gloves were assessed and validated, highlighting the crucial relationship between manufacturing techniques and material properties. Overall, the results indicated that the combination of the additive with a high crosslinking density of NRL effectively improved the material mechanical properties, resulting in a tensile strength of up to 20.7 MPa and a tear strength of approximately 40 kN m−1. In addition, and according to the antibacterial tests, the gloves exhibited bacteriostatic effects against Staphylococcus aureus and bactericidal effects against Escherichia coli. As a conclusion, the dataset indicates that the manufactured cosmetic gloves can be used to covering upper limb prostheses. Additionally, it underscores the considerable potential for the cosmetic glove manufacturing industry through the use of appropriate formulations and processing techniques for NRL.

OBT-Trace: An approach to trace and recognition object motion through prosthetic hand gestures

The development of prosthetic hands has advanced significantly in recent years, aiming to provide more intuitive and functional solutions for individuals with upper limb amputations. This research presents a novel approach to prosthetic hand control by integrating 3D hand gesture recognition with object manipulation and recognition capabilities. Our proposed system utilizes a pre-trained object recognition model, based on transfer learning, to enable the prosthetic hand to perceive and identify objects in its vicinity. The model leverages a vast dataset of objects, enabling the prosthetic hand to recognize a wide array of everyday items, thus enhancing its versatility.In addition, the prosthetic hand incorporates a sophisticated 3D hand gesture recognition system, allowing users to control the hand's movements and actions seamlessly. By recognizing specific gestures, such as grasping, lifting, and releasing, users can intuitively interact with their environment and perform various tasks with ease. This research leverages the synergy between gesture recognition and object recognition, creating a powerful framework for prosthetic hand control. The system's adaptability and versatility make it suitable for a broad range of applications, from assisting with daily tasks to enhancing the quality of life for individuals with upper limb amputations.The results of this study demonstrate the feasibility and effectiveness of combining 3D hand gesture recognition with pre-trained object recognition through transfer learning. This approach opens up new possibilities for enhancing prosthetic hand functionality and usability, ultimately improving the lives of those who rely on these devices for daily living. The proposed model combines the features of YOLO V7 object detection with pre-trained models. The proposed model achieves 99.8% of accuracy compared to the existing models.

Patterns of use of a myoelectric prosthesis in a cohort of children with transverse defects below the level of the elbow.

Myoelectric prostheses have become the accepted standard of care for pediatric upper-limb amputees. To describe the clinical characteristics and patterns of prosthesis use and to analyze the changes that occur during the growth process of these patients. This is a longitudinal retrospective study comparing the results of surveys carried out in 2015 and 2022. The variables measured included clinical and demographic characteristics, patterns of use, and satisfaction with the prosthesis. Twenty-one patients with transverse defects were fitted with myoelectric prostheses. With increasing age, there was a statistically nonsignificant decrease in the duration of use and a decrease in the number of patients using the prosthesis for activities of daily living from 13 to 10 (p = 0.045), with a 28% dropout rate, higher in patients with more distal defects. Since 2015, we have observed a decrease in the number of hours of prosthesis use, while maintaining a high percentage of patients using the prosthesis.