Search Results (518)

The application of functional electrical stimulation (FES) to restore hand motor function remains challenging due to the difficulty of calibrating multi-channel stimulation to produce coordinated finger movements. This study proposes a compositional FES calibration framework to customize the stimulation of isolated finger actions and enable their combination into functional hand gestures. The proposed method was validated through a two-session experimental study involving thirteen participants. In the first session, subject-specific stimulation sites and parameters were identified for eight individual finger movements using a structured spatial grid defined over the forearm. The second session, conducted on a subset of five participants, evaluated the generation of seven hand gestures derived from combinations of the isolated movements. Results showed that ten of the thirteen participants achieved at least six movements, while three participants successfully elicited all targeted motions. Successfully elicited movements were generally well isolated, although thumb and ring/little finger extensions proved more difficult to isolate. The second session demonstrated that individually calibrated finger activations can be combined to produce coordinated multi-finger movement patterns, with average finger excursions matching the expected motions. Overall, these preliminary results support the use of compositional calibration strategies to achieve functional multi-finger control with multi-channel FES. Full article

Objective: To quantify and map bone mineral density (BMD) at the bases of human finger phalanges using computed tomography (CT) with a calibration phantom and to compare BMD both between and within digits. Methods: Ten cadaveric hands (H1 to H10) were CT scanned with a Model 3 CT Calibration Phantom (Mindways). All data were processed in the Horos software (Version 4.0.0) and the regions of interest (ROIs) at each phalangeal base were delineated. Hounsfield Units (HU) were converted to BMD (mg/cm³) per the phantom framework. Descriptive statistics and repeated-measures ANOVA analyses were performed for each digit and corresponding phalangeal level (proximal, middle, distal). Inter-digital comparisons were performed at corresponding phalanx levels and intra-digital variations were analyzed within digits across phalangeal levels. Results: Mean BMD varied across digits and phalangeal levels. At the proximal phalanx base, the thumb and index fingers exhibited the highest values, whereas at the middle phalanx base the middle and ring fingers demonstrated the highest mean BMD values. At the distal phalanx base, the little finger demonstrated the highest BMD value, while the lowest value was observed at the distal phalanx of the index finger. Intra-digital analysis revealed distinct distribution patterns: BMD decreased distally in the thumb and index fingers, peaked at the middle phalanx in the middle and ring fingers, and was highest distally in the little finger. Repeated-measures ANOVA demonstrated statistically significant intra-digital differences in the thumb and index fingers, whereas no statistically significant inter-digital differences were observed across corresponding phalangeal levels. Conclusions: CT-based, phantom-calibrated BMD mapping at the bases of the phalanges demonstrates substantial intra-digital variability and descriptive inter-digital differences. These site-specific findings may provide additional information relevant to implant selection and preoperative planning for fixation in phalangeal fractures and tendon- or ligament-to-bone insertion injuries in hand surgery. Full article

Meta-analysis is a statistical tool commonly used within systematic reviews to synthesize quantitative evidence, but individual studies with atypical results or disproportionate influence can materially affect pooled estimates, heterogeneity estimates, and the conclusions drawn from evidence syntheses. Conventional outlier and influence diagnostics for meta-analysis are useful, but their interpretation often relies on asymptotic reference values or informal rules of thumb, which may be inadequate when the number of studies is limited or heterogeneity is substantial. We introduce boutliers, an R package that implements bootstrap-calibrated outlier detection and influence diagnostics for fixed-effect and random-effects meta-analysis. The package provides leave-one-study-out diagnostics based on Studentized deleted residuals, relative changes in the variance of the pooled effect estimator, and relative changes in the between-study variance, together with a likelihood-ratio diagnostic based on a mean-shifted model. For each diagnostic measure, bootstrap reference distributions, critical values, and p-values are provided to support quantitative interpretation of influential studies. We describe the statistical framework, implementation, and practical use of the package and illustrate its application using a real published meta-analysis dataset on spinal manipulative therapy for chronic low back pain. The boutliers package provides accessible tools for incorporating uncertainty-calibrated influence diagnostics into routine meta-analytic practice. Full article

Truck-to-excavator assignment is a time-critical control problem in open-pit earthmoving systems (mines, quarries, and large cut-and-fill construction sites) where stochastic travel and service times, changing queues, and equipment outages continually alter the best dispatch decision. A deep reinforcement learning (DRL) dispatch policy is developed and trained using a discrete-event simulation (DES) digital twin of the Sungun copper mine haulage system. The dispatch task is formulated as a Markov decision process using state features that represent fleet locations, excavator and dump queues, and short-term congestion conditions. The resulting deep artificial neural network (DANN) policy is tuned via systematic hyperparameter optimisation and evaluated against a priority-based rule-of-thumb dispatch baseline under long-horizon operating tracks. Results show that the final trained policy improves the average production rate per truck cycle by approximately 17% while reducing avoidable waiting and maintaining stable performance over extended operation, with inference fast enough for real-time dispatch use. Model fidelity is supported by close agreement between simulated and observed daily completed-cycle counts. Robustness is assessed through controlled truck load-capacity perturbations, and scalability is examined through fleet-size sensitivity, which reveals diminishing returns as additional trucks are added under a fixed excavation–haulage configuration. Practical deployment considerations and implications for construction earthmoving logistics are discussed. Full article

Background: Hand Hygiene (HH) plays a crucial role in preventing Hospital-Acquired Infections (HAIs), yet compliance and technique often remain inadequate. To our knowledge, this study is among the first large-scale Semmelweis Scanner-based evaluations of hand hygiene technique among both medical and non-medical students in Uzbekistan and the wider Central Asian region. Methods: A cross-sectional study was conducted between March 2024 and July 2025 at the Tashkent Medical Academy and the Tashkent State Technical University, resulting in 4191 data scans and 16,764 pictures analyzed. Hand surface coverage was evaluated using the Semmelweis digital monitoring system, which provides image-based feedback on insufficiently covered areas. Adequate performance was defined as achieving at least 95% hand surface coverage. Results: The findings showed that only 43.4% of hand hygiene measurements achieved the ≥95% hand coverage threshold, while 56.6% showed incomplete coverage. The sixth WHO-recommended step, i.e., rotational rubbing of the thumb and fingertips was identified as the most frequently missed moment. Significant variation was observed across faculties and departments, with bachelors achieving the highest success (n = 1012, 51.8%) and Ph.D. students reaching the lowest (18.4%). Conclusions: Hand hygiene technique among students in Uzbekistan is highly variable and frequently inadequate when evaluated using scanner-based digital assessment. The findings suggest that incomplete hand surface coverage, rather than the absence of sanitization attempts, is the principal challenge. Digital hand hygiene monitoring systems can provide an effective complementary tool for technique-focused education and can support infection prevention practices in both medical and non-medical training environments. Full article

Stray-current corrosion from DC-electrified railways drives premature failure of buried metallic infrastructure (pipelines, foundations, tunnel reinforcement), causing resource waste, repair-driven carbon emissions and service disruptions that undermine the sustainability of urban transit corridors. Conventional impressed-current cathodic protection (ICCP) design relies on uniform-anode rules of thumb or closed commercial codes that cannot quantify the trade-off between protection uniformity, energy use and hardware cost. We present an open MATLAB framework that couples a custom 3D finite element method (FEM) solver with multi-objective particle swarm optimisation (MOPSO) and minimises three competing objectives simultaneously: total impressed current, RMS deviation from the protection target, and number of active anodes. A laboratory-calibrated coupling factor ($\mathrm{CF}=1.98$, consistent with the image-method prediction of 2 for a highly conductive pipe inclusion) absorbs the pipe–soil interface kinetics into a single direct FEM solve, and a pre-computed Green’s-function basis accelerates each MOPSO evaluation by more than two orders of magnitude. The solver is validated against an instrumented prototype with RMSE $=14.9$ mV across ten Cu/CuSO₄ saturated reference electrode (CSE) measurements, and applied to a 500 m DC traction line. At an identical total current of 20.30 A across five anodes, the optimised design achieves an RMSE of 86.6 mV against the $-850$ mV NACE target, whereas a conventional uniform layout produces severe over-protection (RMSE $=1107$ mV)—a twelve-fold reduction. The framework is recommended as a transparent, reproducible engineering tool that simultaneously extends pipeline service life and reduces rectifier energy demand, supporting UN Sustainable Development Goals 9 and 11 for sustainable urban-rail infrastructure. Full article

Thumb degree-of-freedom (DOF) allocation in anthropomorphic robot hands involves a trade-off between functional mobility and mechanical-control complexity. This study presents a controlled multi-metric framework for comparing recurring thumb DOF configurations under common palm geometry, non-thumb finger structure, reference frames, Denavit–Hartenberg kinematics, and sampling assumptions. Five literature-derived thumb configurations, namely 3-1-1, 2-2-1, 2-1-1, 2-0-1, and 1-1-1, were evaluated to determine which thumb DOFs should be preserved when kinematic complexity is reduced. The theoretical evaluation included Kapandji Opposition Test reachability, opposition alignment, workspace volume, workspace compactness, cylindrical grasp opportunity, and Jacobian-based dexterity. A targeted experimental validation of the 2-1-1 and 2-0-1 prototypes was then performed on a tendon-driven test bench. The results showed that qualitatively similar thumb configurations are quantitatively unequal: several designs achieved identical Kapandji scores but differed substantially in workspace, alignment, dexterity, and grasp feasibility. Overall, 3-1-1 achieved the strongest overall capability, while 2-2-1 emerged as the strongest reduced-complexity alternative and achieved the best mean dexterity. Retaining two active carpometacarpal DOFs preserved a large share of dexterous function, whereas metacarpophalangeal fixation maintained selected cylindrical grasps but narrowed the feasible task boundary. Full article

Traumatic thumb loss causes severe functional impairment, as the thumb provides approximately 40% of total hand function. Toe-to-thumb transfer remains the gold standard for thumb reconstruction, yet donor site morbidity represents a significant functional and aesthetic limitation. A total thumb reconstruction using a “trimmed” right great toe transfer, combined with immediate donor site reconstruction using a free SCIP (superficial circumflex iliac perforator) flap and iliac crest bone graft. The flap was designed as a tubular skin island to create a neo-hallux with optimal contour and volume, minimizing visible scarring and avoiding microcirculatory compression. The patient, a 33-year-old man with post-traumatic thumb avulsion, underwent delayed reconstruction three months after injury. The postoperative course was uneventful, with no vascular or wound complications. At 12 months, he resumed full ambulation and manual activities, including motorcycle driving and work tasks. Baropodometric analysis demonstrated symmetric load distribution and gait dynamics. Thumb opposition was satisfactory (Kapandji score: seven); the patient rated the aesthetic results as excellent. This case demonstrates that SCIP flap reconstruction with iliac crest bone graft enables complete functional and aesthetic restoration of the great toe donor site after total toe transfer. Compared to previous techniques using cross-flaps, skin grafts, or peroneal flaps, this approach minimizes morbidity, optimizes cosmetic outcomes, and preserves gait. Although representing a single case, this constitutes the first documented instance of total hallux reconstruction following toe-to-thumb transfer, emphasizing the importance of the foot as a functional and aesthetic unit and the need for donor-site preservation in microsurgical reconstructive planning. Full article

Background: Several surgical techniques are available for the treatment of thumb trapeziometacarpal (TMC) osteoarthritis. Trapeziectomy with ligament reconstruction and tendon interposition (LRTI) is a widely accepted procedure, while suspensionplasty techniques have been introduced to improve first metacarpal stability after trapeziectomy. A simplified transosseous suture suspensionplasty (SUSP) has recently been introduced as an alternative to implant-based constructs, but comparative clinical data remain limited. This study aimed to compare the clinical and functional outcomes between LRTI and SUSP techniques in patients with TMC osteoarthritis. Methods: A retrospective comparative study was conducted on 54 consecutive patients treated surgically for TMC osteoarthritis between 2018 and 2022. Thirty-three patients underwent trapeziectomy with ligament reconstruction and tendon interposition (LRTI group), and 21 underwent trapeziectomy with transosseous suture suspensionplasty (SUSP group). At a minimum follow-up of 2 years, 44 patients were available for evaluation. Assessments were performed using DASH, 10 cm VAS, key pinch strength, Kapandji score, and radial/palmar abduction. Results: At 2 years, there were no significant between-group differences in DASH (median 4 vs. 16.5; p = 0.190), VAS (2.0 ± 2.1 vs. 2.9 ± 2.3; p = 0.235), key pinch (median 4 vs. 3 kg; p = 0.136), Kapandji score, or abduction. Both groups improved significantly over time in DASH and VAS (p < 0.001). Key pinch increased progressively in LRTI group (p < 0.001) but showed less consistent change in SUSP group. Conclusions: Both techniques provided comparable mid-term clinical and functional outcomes in patients with TMC osteoarthritis. No clear clinical advantage of suspensionplasty over tendon interposition was demonstrated. Transosseous suture suspensionplasty represents a valid alternative, while tendon interposition arthroplasty remains a reliable reference technique. Full article

Objectives: The aim of this study was to evaluate the psychometric properties of the Pain Catastrophizing Scale (PCS) in patients with carpometacarpal osteoarthritis of the thumb. Methods: In this cross-sectional register-based study of 253 patients with carpometacarpal osteoarthritis of the thumb, a two-parameter item response theory analysis was used to evaluate the items’ difficulty and discrimination parameters. Results: Of 253 patients, 245 (57%) were women. The mean age was 56.0 (SD 16.5) years. The mean total PCS score was 14.0 (SD 10.5) points. Difficulty estimates were distributed fairly evenly across the item score scale, with a slight shift towards higher scores. Discrimination of both total and subscale scores was perfect, varying from 1.91 to 2.84. Conclusions: PCS was able to discriminate well between different levels of catastrophizing. PCS performed slightly more accurately when the catastrophizing level was above average in the studied sample. PCS can be recommended for clinical use when assessing catastrophizing in patients with carpometacarpal osteoarthritis of the thumb. Full article

To meet daily grasping needs under lightweight, low-complexity wearable constraints, this study proposes an underactuated multi-finger prosthetic hand with transmission–control co-design to achieve predictable multi-joint synergies and stable grasps under limited actuation. The prototype uses six miniature motors to drive 14 joint degrees of freedom (DOFs): four fingers have active metacarpophalangeal actuation with tendon-driven underactuated proximal and distal interphalangeal joints, while the thumb provides two independently controlled DOFs for opposition expansion and posture adjustment. It supports five-finger power grasps, tripod pinches, and lateral pinches. To mitigate tendon slack and stroke inconsistency, active/passive tendon-length constraints are defined, and an equal-stroke configuration is obtained via chord-to-arc mapping. A layered STM32F767-based controller combines a reference rotation range limit (free motion) with encoder speed-decay detection (contact/near-stall) to realize per-finger termination and overdrive protection without force/tactile sensors. Experiments report a total mass of 176.6 g and a peak single-finger driving force of approximately 2.8 N. Following the Feix GRASP taxonomy (33 types), the hand reproduces 24 types (72.7%), covering power, intermediate and precision grasps, both thumb abduction/adduction postures, and palm–pad–side opposition/contact, with stable grasp formation across objects of varying geometries. Full article

As robotics prehension systems and virtual reality applications are in constant evolution, the need for high-fidelity haptic interaction increases. This helps ensure and enhance user immersion and handling precision. While commercial haptic interfaces offer high performance, their prohibitive cost limits their widespread adoption in general-purpose robotics. Furthermore, many low-cost solutions suffer from limited transparency, where the operator constantly fights the friction of the actuator even during free motion. This article presents the design and development of an innovative, cost-effective master–slave robotic system aimed at democratizing efficient haptic feedback devices. The solution is intended for remote manipulation of objects with a maximum mass of 1 kg, while limiting the gripping force to 50 N, thus ensuring the integrity of objects being manipulated. The device includes a master haptic module in the form of a clamp that reproduces the thumb–index–middle finger gripping motion performed by the user. The system relies on a custom haptic interface measuring the angular position of the master gripper, which is transmitted in real time to the slave gripper, so as to adjust the position of the clamp accordingly, thus optimizing the grasping control loop. As soon as an object is detected, using a force sensor integrated into the slave gripper, the master motor renders a resistive force, preventing the user from closing the haptic module. The other part of the system is the slave mechanical gripper with three fingers, each with three phalanges based on human anatomy, allowing the clamp to mechanically conform to irregular object geometries with a single actuator. The last but not least innovative aspect lies in the implementation of a current sensor, which provides the haptic feedback. The force applied by the user is reproduced by the slave gripper using current sensors, eliminating the need for expensive force-torque sensors while maintaining a responsive feedback loop. Full article

Background: Trapeziometacarpal (TM) osteoarthritis (OA) is a common condition, especially among postmenopausal women, often requiring surgical intervention when conservative treatment fails. In recent years, dual-mobility prostheses have been increasingly used as an alternative to traditional trapeziectomy with suspension arthroplasty. However, limited data exist regarding their comparative cost-effectiveness in public healthcare systems. Purpose: The aim of this study was to compare the cost–benefit ratio and clinical outcomes of two surgical techniques for TM OA: trapeziectomy with suspension arthroplasty and total joint arthroplasty with a dual-mobility prosthesis. Methods: We conducted a retrospective cohort study of 116 hands treated between 2020 and 2024. Patients were divided into two groups based on the surgery they received: trapeziectomy with suspension arthroplasty or implantation of a dual-mobility TM prosthesis. Clinical outcomes were assessed using VAS, DASH, Kapandji score, grip strength, and pinch strength at 12, 36, and 48 months postoperatively. A cost analysis was performed based on hospital reimbursement (Diagnosis-Related Group) and estimated productivity loss. Results: Both techniques yielded significant improvements in pain and function. Patients who were operated on with a prosthesis showed faster recovery and better early outcomes, while the trapeziectomy group had lower direct surgical costs and fewer complications. At 48 months, clinical scores were comparable. The overall cost–benefit ratio favoured trapeziectomy with suspension arthroplasty, while TM prosthesis’s higher costs were justified due to improved short-term functional recovery. Conclusions: Both surgical techniques achieved satisfactory long-term clinical outcomes. The prosthetic option allows for quicker recovery and reduces indirect social costs, while suspension arthroplasty remains more cost-effective for direct costs. These findings highlight the importance of balancing clinical benefit and economic sustainability in surgical decision-making for TM osteoarthritis. Level of Evidence: Level III, retrospective comparative study. Full article

Electronic sport (esport) refers to competition in video games. Injuries in esports have hardly been studied so far. A total of 1229 e-athletes of all levels and genres answered a retrospective questionnaire about injuries and overuse damages that occurred in the course of their careers. The average age of the 1229 participants was 23.8 ± 5.5 years. A total of 198 (16.1%) of the e-athletes take part in competitions. The most common injury location was the trunk/spine (319, 26.0%) followed by the wrist region (225, 18.3%). Degenerative and overuse injuries were in the foreground. Professional athletes were injured more frequently than amateur athletes (p = 0.006). Tactical shooter players have significantly more injuries than sports game players (p = 0.021) and MMO (Massively Multiplayer Online) players (p = 0.042). E-athletes are just as susceptible to injury as athletes in traditional disciplines. The high injury rate is certainly not due to acute injuries but to overloading and overuse injuries, with a focus on the thoracocervical area and the upper extremities. Terms such as “Nintenditis”, “gamer’s thumb” and “PlayStation thumb”, which describe injuries caused by repetitive strain, are becoming increasingly common. Injuries in esports should be taken seriously, as they can cause long-term health problems in the event of overuse injuries. Prevention is a critical and promising approach for such a young patient clientele, especially in a sport that is growing so rapidly and is unknown to the majority. Full article

Background/Objectives: Hand loss or severe impairment significantly reduces quality of life by restricting essential daily activities and professional tasks. Despite advances in prosthetics, challenges remain in affordability, accessibility, and usability. This study aimed to design and develop a low-cost, ergonomic bionic hand prototype that integrates sustainable fabrication, intuitive control, and modular electronics. Methods: A user-centred design process guided by iterative prototyping, anatomical modelling, and functional validation. The prototype was manufactured using 3D printing techniques and assembled with modular electronic components. The design included segmented fingers, independent thumb articulation, and a tendon-like actuation system driven by micro-motors. Control was implemented through an ESP32-based board and a Bluetooth-enabled mobile application. Durability was preliminarily assessed through 500 grasp–release cycles. Results: Experimental validation confirmed the feasibility of both precision and power grips. The pinch grip successfully lifted objects to 120 g, and the power grip up to 85 g, corresponding to effective output forces of approximately 1.2 N and 0.83 N, respectively. The final prototype weighed ~350 g and maintained reliable performance during 500 grasp–release cycles. Conclusions: The developed bionic hand demonstrates that an affordable, ergonomic, and functional prosthetic can be achieved through sustainable 3D printing and accessible electronics. Future work will focus on enhancing actuation strength, long-term durability, and integration of sensory feedback, with the long-term objective of clinical testing and scalable production. Full article