Search Results (1,164)

Hand range of motion (ROM) measurement is crucial for diagnosing joint limitations, tracking rehabilitation progress, and creating personalized treatment plans. In recent years, exergames combined with dedicated game controllers have emerged as promising tools to complement traditional hand rehabilitation; however, their validity as motor function assessment tools remains insufficiently explored. This study evaluates the validity of the eJamar game controller as a tool for measuring hand ROM and hand grip strength (HGS), by comparing its outputs with standard goniometry and dynamometry. In a prior technical validation using a robotic arm under controlled conditions, the device showed a mean error of approximately 1.5°, indicating high measurement precision under ideal conditions. In the clinical validation with 32 patients undergoing hand rehabilitation, performance was movement-dependent. Pronation and supination showed strong agreement (MAE < 3°) and higher agreement compared with other movements, whereas flexion, extension, and radial-ulnar deviation exhibited weaker correlations and substantially higher errors (around 20°). In contrast, grip strength measurements for more and less affected hands, respectively, showed high correlation (0.88–0.91) and moderate agreement (ICC 0.81–0.66) with MAE values around 4 kg-f. Overall, results suggest that the eJamar shows preliminary suitability for assessing HGS and forearm pronation and supination in clinical settings. However, for HGS, agreement should be interpreted with caution due to the observed bias and error levels, indicating that further validation and calibration are required before stronger clinical claims can be made. For wrist flexion, extension, and radial-ulnar deviation, the device currently shows limited accuracy and requires further improvement. Full article

Background/Objectives: Proximal phalangeal fractures account for 38% of all phalangeal fractures, with unstable patterns requiring surgical intervention. Various modalities have been explored, including open reduction and internal fixation, percutaneous K-wire fixation, and intramedullary techniques. This study explores the technical nuances, indication, and outcomes of antegrade cannulated compressive screw (CCS) fixation of proximal phalangeal fractures. Methods: This retrospective case series involved 18 closed proximal phalangeal fractures in 16 patients who underwent intramedullary headless screw fixation between January 2018 and December 2023. Records were reviewed for demographics, fracture characteristics, and screw type. With the metacarpophalangeal joint flexed at 60–75°, a 1 cm longitudinal incision was made, the extensor tendon split, and a 0.9 mm guidewire advanced anterogradely along the phalangeal axis under fluoroscopy. A 2.2 mm or 3.0 mm SpeedTip CCS was selected based on phalanx size and advanced until fully buried below the cartilage line. Postoperatively, patients were immobilized in a volar intrinsic-plus splint, transitioned to a gutter splint within five to seven days, and commenced on range of motion (ROM) exercises within one week. Primary outcomes included radiographic union, Total Active Motion (TAM), QuickDASH scores, and postoperative complications. Results: All fractures were healed within acceptable radiological parameters and with no postoperative complications. Mean TAM was measured to be 216.0° (SD 7.7°, range 200–230°) and mean QuickDASH was 10.1 (SD 2.8, range 5–16). Conclusions: Antegrade intramedullary headless screw fixation demonstrates feasibility, short-term safety, and excellent early functional outcomes for carefully selected unstable proximal phalanx fractures, supporting its role as a minimally invasive alternative in appropriately indicated cases. Full article

Background/Objectives: Trapeziometacarpal osteoarthritis (TMC OA) is a common disabling condition. This study compared clinical and radiographic outcomes of trapeziectomy with suspension arthroplasty and dual mobility TMC joint replacement in a prospective comparative cohort study design. Methods: A prospective comparative study was conducted on 122 patients contributing 129 hands with Eaton–Littler stage II–III TMC osteoarthritis. Patients were treated with trapeziectomy with suspension arthroplasty (58 patients, 60 hands) or TMC joint replacement with a dual mobility prosthesis (64 patients, 69 hands), based on surgical indication and shared decision-making. Clinical and radiographic evaluations were performed up to 24 months postoperatively. Results: Both techniques significantly improved pain, function, range of motion, and strength (p < 0.05). Joint replacement provided faster pain relief and functional recovery, with superior strength at all follow-up points. At 12 months, pain and functional outcomes were comparable between groups. No implant loosening or failures were observed. Conclusions: Both surgical techniques are effective for TMC osteoarthritis. Dual mobility TMC joint replacement allows faster recovery and greater strength, while achieving comparable mid-term clinical outcomes to suspension arthroplasty. Full article

Background: Joubert syndrome (JS) is a rare neurodevelopmental ciliopathy characterized by cerebellar and brainstem malformation and heterogeneous motor outcomes. Although global developmental delay is well described, integrated clinical characterization combining functional and structural domains remains limited. The aim of this exploratory study was to describe a multidimensional motor phenotype in children with JS and to explore associations between selected functional and structural parameters. Methods: A prospective cross-sectional cohort study was conducted in 25 children with MRI-confirmed JS (aged 2–16 years). Gross motor performance was assessed using the GMFM-88, and postural control was evaluated with the modified Brief Ataxia Rating Scale (mBARS). Measured musculoskeletal parameters included joint range of motion and sacral slope as an indicator of sagittal pelvic alignment. Thoracoabdominal configuration was assessed using angular and anthropometric measurements. Associations between predefined functional and structural variables were explored using Spearman’s rank correlation coefficients. Analyses were exploratory and hypothesis-generating and were not adjusted for multiple comparisons. Results: Marked inter-individual variability was observed across functional and structural domains. A moderate negative correlation was identified between GMFM-88 (Gross Motor Function Measure-88) and mBARS (modified Brief Ataxia Rating Scale) scores (ρ = −0.512, p-value = 0.007). Sacral slope demonstrated statistically significant associations with hip extension, ankle dorsiflexion, chest and abdominal circumference, and sternoclavicular alignment (all p-value < 0.05). No significant correlations were detected between gross motor performance and isolated structural parameters. Intra-rater reliability of selected measurements was high (ICC range 0.939–0.999). Conclusions: This exploratory, hypothesis-generating study demonstrates multidimensional variability in motor organization encompassing functional, postural, and structural domains. Gross motor performance appears more closely related to postural control than to isolated peripheral structural measures within this exploratory framework. Structural parameters exhibit internal statistical co-variation but do not independently determine functional capacity. These findings support the value of integrated multidomain physiotherapy assessment in rare cerebellar neurodevelopmental disorders. Full article

Background and Clinical Significance: Post-traumatic finger stiffness is frequently attributed to soft tissue adhesions; however, mechanical obstruction from occult osseous structures remains a rare but critical differential diagnosis in adults. Case Presentation: This report describes a 56-year-old female presenting with severe, refractory stiffness of the little finger eight months after a proximal phalanx fracture. Despite extensive conservative therapy, active and passive flexion at the proximal and distal interphalangeal joints remained locked in extension. While conventional radiographs demonstrated bony union, musculoskeletal ultrasonography (MSUS) revealed an occult protruding malunited fragment incarcerating the flexor tendons. Dynamic MSUS provided real-time evidence of mechanical impingement by demonstrating proximal muscle contraction without distal tendon excursion. Intraoperatively, initial soft tissue tenolysis failed to restore motion; further exploration guided by MSUS evidence successfully identified a sharp bone spike. Subsequent ostectomy resulted in immediate restoration of functional range of motion. This case underscores the limitations of static imaging in evaluating the dynamic gliding mechanism and highlights the valuable role of MSUS in identifying mechanical functional obstructions. Conclusions: Early sonographic evaluation should be considered for refractory post-traumatic stiffness to prevent prolonged, ineffective conservative care and to guide definitive surgical management. Full article

This paper presents a low-cost retrofitting pipeline for a legacy industrial robot that uses a single RGB webcam and monocular 2D keypoint tracking to estimate human-arm posture angles ${\mathit{\theta }}^{\left(\mathrm{h}\right)}$ and map them to robot-axis joint targets ${\mathbf{q}}_{\mathrm{cmd}}^{\left(\mathrm{r}\right)}$ for A1–A3 on a KUKA KR5-2 ARC HW, while keeping the wrist orientation (A4–A6) fixed. Rather than targeting full six-DoF manipulation, the main contribution is an experimental characterization of how far monocular 2D posture-to-axis mapping can be used reliably for coarse placement and safeguarded low-speed demonstrations on a legacy robot platform. Vision-side accuracy was evaluated per axis against goniometer-based reference angles ${\mathit{\theta }}_{\mathrm{ref}}^{\left(\mathrm{h}\right)}$, showing low errors for A2–A3 within the tested range and larger errors for A1 due to monocular yaw/depth ambiguity and occlusions. The study also analyzes failure modes during simultaneous multi-joint motion, where performance degrades notably, especially for A2 and A3, and reports practical mitigation directions such as improved viewpoints, multi-view/depth sensing, and stricter dropout handling. Runtime behavior is additionally characterized through a loop timing budget, with an end-to-end latency of 185.44 ms and an effective loop frequency of 5.39 Hz, which is consistent with low-speed online operation within the demonstrated scope. The system was implemented in a fenced industrial cell with restricted access and emergency stop; no collaborative operation is claimed. Full article

Objective: Functional training exercises involve complex multi-joint movements that challenge traditional rule-based or data-driven recognition systems. This paper introduces a Movement Description Language (MDL) designed to formally represent, analyze, and evaluate such exercises using camera-based pose estimation and interpretable, composable structures. Methods: The proposed MDL models each exercise as a finite-state machine defined by pose-derived angle proxy transitions, allowing movements to be described in a modular and reusable way. Demonstrated with MediaPipe landmark extraction from monocular video, while the MDL remains compatible with any pose estimation algorithm, the framework focuses on exercise phase detection and repetition counting. Experimental validation was conducted on a dataset of 1513 videos of 12 functional exercises (squats, deadlifts, lunges, shoulder presses, planks, push-ups, pull-ups, bent-over rows, box jumps, thrusters, overhead squats, and burpees) obtained from public pose datasets, competition footage, and recordings of 9 participants in real-world environments. Results: Automated repetition counts were compared against manually annotated ground truth, showing an overall repetition-counting accuracy of 97.2%, with a mean per-exercise accuracy of 98.8% (range 95–100%). The MDL successfully handled both simple and compound exercises, maintaining reliable phase detection despite variations in execution speed, camera perspective, and environmental conditions. Conclusion: The system was implemented using real-time pose estimation to demonstrate the practical execution of the MDL framework. The proposed MDL provides a transparent, extensible, and computationally efficient framework for functional exercise analysis. By bridging human-readable movement semantics with executable motion logic, it enables interpretable automatic repetition counting and phase detection, offering an alternative to black-box recognition approaches. The results support its potential for scalable deployment in training, monitoring and movement analysis applications. The proposed system is not intended for biomechanical measurement or clinical-grade kinematic analysis, but rather for interpretable modeling of exercise structure and repetition detection using approximate pose-derived signals. Full article

Mongolian horses are an indigenous Chinese breed known for their endurance capacity, yet quantitative descriptions of their gait-related kinematic characteristics remain limited. This pilot exploratory study aimed to describe the kinematics of Mongolian horses during walk, slow trot, and fast trot, and to examine whether selected variables differed between race-result groups in a 12 km endurance race. Forty-six horses were classified into an excellent group and an ordinary group based on the result of a single race. Kinematic data were collected using optical motion capture and three-dimensional skeletal modelling. Separate gait-specific linear mixed-effects models were fitted, with horse identity as a random effect and group and speed as fixed effects. The results showed gait-dependent between-group differences. During walk, the excellent group had significantly greater range of motion of the tarsal, hip, and elbow joints, as well as a greater maximum forelimb retraction angle (all p < 0.001). During slow trot, the excellent group showed significantly greater stride length (p = 0.009), elbow joint range of motion (p < 0.001), minimum hindlimb forward extension angle (p = 0.033), and minimum forelimb forward extension angle (p = 0.004). During fast trot, the between-group differences were most pronounced, with significantly greater stride length (p < 0.001) and range of motion of the tarsal joint (p < 0.001), hip joint (p = 0.015), and elbow joint (p = 0.014), together with greater maximum hindlimb retraction angle (p = 0.001) and minimum forelimb forward extension angle (p = 0.026). Overall, these findings provide preliminary evidence that gait-related kinematic differences may exist between race-result groups in Mongolian horses. However, because this was an exploratory study based on a single race, the findings should be interpreted cautiously and require validation in larger and more diverse cohorts. Full article

This paper presents a lightweight MATLAB-based framework with a graphical interface for modeling, 3D simulation, trajectory generation, and experimental validation of a 6-DOF industrial robot. The platform integrates kinematic modeling using the rigidBodyTree structure, animated visualization, and both predefined and user-defined trajectory planning within a unified environment. A central aspect of the proposed approach is the implementation of a ROS-compatible TCP/IP communication protocol that avoids the need for a full ROS core installation while preserving compatibility with ROS-Industrial standards. This enables bidirectional data exchange between MATLAB and the robot controller within a simplified architecture. Communication performance tests indicate round-trip latency in the tens-of-milliseconds range and consistent StateServer update rates, supporting monitoring, trajectory execution, and digital twin synchronization in non-real-time conditions. Experiments conducted on an ABB IRB120 robot demonstrate a close correspondence between simulated and real motion, with RMSE below 0.0075 rad and MAE below 0.0065 rad across all joints. All data are stored in JSON format to support reproducibility and further analysis. By integrating simulation and real robot execution within a modular architecture, the proposed framework provides a practical tool for education, rapid prototyping, and experimental research in industrial robotics, while offering a basis for future extensions toward advanced control strategies and digital twin applications. Full article

Background: Chronic venous insufficiency (CVI) is characterized by venous dysfunction in the lower extremities, leading to increased venous pressure, edema, and reduced quality of life. Objectives: This study aimed to evaluate the additional effect of a structured home-based calf muscle strengthening exercise program when combined with standard compression therapy, by comparing disease severity, musculoskeletal function, and quality of life over time between patients receiving compression therapy alone and those receiving combined intervention. Methods: A randomized controlled trial was conducted in 50 patients with CVI (CEAP C₃–C₅), who were assigned to an experimental group (n = 25) and a control group (n = 25). Outcomes were assessed at baseline, week 6, and week 12. Disease severity was measured using the Revised Venous Clinical Severity Score (rVCSS), and swelling, muscle, and joint function were assessed using calf muscle strength and ankle range of motion. Quality of life outcomes were assessed using the chronic venous disease quality of life questionnaire (CIVIQ-20). Data were analyzed using two-way repeated measures ANOVA. This trial was registered retrospectively at the Thai Clinical Trials Registry (registration number: TCTR20260307002). Results: Significant group × time interaction effects were observed for disease severity (right leg: F = 81.562, p < 0.001, η²p = 0.630; left leg: F = 73.765, p < 0.001, η²p = 0.606), indicating greater improvement in the experimental group over time. Calf muscle strength significantly increased in the experimental group (right leg: F = 395.246, p < 0.001, η²p = 0.892; left leg: F = 87.278, p < 0.001, η²p = 0.645). Ankle range of motion also improved significantly (p < 0.001). Quality of life showed significant improvement with a group × time interaction effect (F = 66.104, p < 0.001, η²p = 0.579). Conclusions: A structured home-based calf muscle strengthening exercise program combined with compression therapy produced significant improvements in disease severity, musculoskeletal function, and quality of life over time, demonstrating an additive therapeutic effect in patients with CVI. Full article

The query propagation paradigm provides a unified theoretical framework for end-to-end multi-object tracking, yet it still faces challenges in complex scenarios involving multi-scale variations, dense interactions, and trajectory fragmentation, including insufficient query initialization quality, imprecise feature alignment, and difficult identity recovery. Building upon MOTRv2, this paper proposes three core improvements. First, we design a geometric prior injection strategy based on sine–cosine encoding, which explicitly encodes target location and scale information into detection queries, providing high-quality initialization for tracking queries. Second, we propose a width–height-modulated deformable attention mechanism that dynamically adjusts the sampling range of deformable convolution according to target size, enabling fine-grained feature matching for multi-scale targets. Third, we construct a motion-direction-consistency-based trajectory re-association module that leverages motion continuity to efficiently recover lost trajectories without introducing additional appearance models. Furthermore, we introduce a progressive joint training strategy that optimizes detection and tracking modules in stages, effectively mitigating gradient competition in multi-task learning. Extensive quantitative and qualitative experiments on the BEE24, UAVSwarm, and VTMOT infrared datasets validate the effectiveness of the proposed method. On the UAVSwarm dataset, our method achieves state-of-the-art performance with 52.4% HOTA, 72.1% MOTA, and only 51 identity switches. Ablation studies further reveal the synergistic enhancement mechanism among the proposed modules. Full article

Compliant mechanisms have contributed to many advances in soft robotics, and there is strong motivation to translate these ideas to assistive devices where adaptive motion at the human interface is required. This work presents novel reconfigurable compliant joints (RCJs) as a parameterized joint element for functional biomimicry in lower-extremity joints for prosthetic knees and ankle–foot orthoses, with concepts that extend to other limb joints. The RCJ uses a rigid hub and outer ring joined by an array of flexible links with centerlines defined by cubic Bézier curves. Link shapes are organized into four Bézier classes (A–D), with base types using 10, 12, or 14 uniformly distributed link slots and variants generated by modifying active-link count and distribution, forming a structured morphology space of 12 configurations for machine design. Dual-extrusion 3D-printed prototypes are characterized by a custom testing apparatus using a 2.2 kN load cell at 25 mm/s over a 0–90° rotation range across six recorded load cycles to measure torque–angle curves and stiffness under large deformations. Angle-dependent stiffness is evaluated over three fixed intervals (0–30°, 30–60°, and 60–90°) to quantify multi-stage behavior. A 2-dimensional corotational frame model and a Simscape Multibody model, including a rolling-contact knee configuration, use the same parameterization to relate geometry, nonlinear mechanics, and system-level motion. Experiments and simulations show multi-stage torque–angle profiles and predictable stiffness modulation across all configurations, with both magnitude and transition angle tunable through Bézier class and active-link distribution, positioning the RCJ as a CAD/CAE-compatible joint architecture for assistive devices or wearable robotic systems and a basis for advancing functional biomimicry in compliant mechanism design. Full article

This study systematizes the form generation process using machine learning-driven motion-tracking data and investigates the interrelationships between the characteristics of generated data and forms generated according to data-processing methods. Through the vision-based machine learning motion estimation (VideoPose3D) algorithm, 3D motion data are extracted from 2D video and categorized into point (joint), curve (bone), and boundary (range of motion) types. Furthermore, this study analyzes the form generation characteristics and limitations associated with each type of motion-tracking data derived from dynamic-to-dynamic physical activities with postural transitions. A data-processing methodology based on artistic practice from prior research is applied. The characteristics of generated data and the morphological characteristics of generated forms are then analyzed according to non-processed and processed methods. Results suggest a potential correlative tendency between the characteristics and generated forms of each type of motion data value information. A bidirectional complementary relationship exists between non-processed and processed motion-tracking data. The data-based form generation methodology demonstrates potential applicability in architectural design. This study expands design possibilities by supporting decisions early in the architectural design process and immediately generating diverse alternatives; it also proposes a standardized framework for a universal data-centric design process applicable to diverse data types, including motion data. Full article

Understanding knee kinematics during gait is essential for the design of prostheses, orthoses, and biomimetic mechanisms. In many biomechanical analyses, tibiofemoral motion is simplified to the sagittal plane, allowing the locus of the instantaneous center of rotation (ICR) to describe joint kinematics derived from the instantaneous axis of rotation (IAR). However, it remains unclear whether ICR trajectories obtained from simplified flexion–extension tasks can represent those observed during gait. This study analyzes the sagittal-plane trajectory of the tibiofemoral ICR during gait swing, standing swing, seated swing, and squat. Motion data from 21 healthy participants were captured using videogrammetry, and the instantaneous axis of rotation (IAR) was computed from homogeneous transformation matrices using the Mozzi–Chasles theorem. Sagittal-plane ICR trajectories were derived and compared within subjects across tasks. Significant differences were found between gait and all other movements in both trajectory shape and spatial position. The shape metric (S), which quantifies differences in trajectory geometry, showed mean values ranging from 0.82 to 1.04 with very large effect sizes (Cohen’s d = 2.90 to 4.47, p < 0.0001). The centroid distance metric (M), which measures the overall spatial displacement between trajectories, indicated positional differences ranging from 8.15 mm to 12.37 mm between trajectories also showing very large effect sizes (Cohen’s = 1.72–3.40, p < 0.0001). Additionally, the mean deviation of the IAR from the sagittal plane ranged from 14° to 18° during gait, whereas smaller deviations were observed in non–weight-bearing swing movements. These results demonstrate that tibiofemoral ICR trajectories are task-dependent and that simplified flexion–extension tasks do not fully reproduce the knee kinematics observed during gait. Consequently, the use of gait-derived ICR trajectories, together with their variability, provides a more suitable basis for the design and optimization of polycentric mechanisms, enabling the development of devices that more closely replicate real biomechanics and are potentially better adapted to the user. Full article