Joints Of Upper Limb Research Articles

Improved Surface Electromyogram-Based Hand–Wrist Force Estimation Using Deep Neural Networks and Cross-Joint Transfer Learning

Deep neural networks (DNNs) and transfer learning (TL) have been used to improve surface electromyogram (sEMG)-based force estimation. However, prior studies focused mostly on applying TL within one joint, which limits dataset size and diversity. Herein, we investigated cross-joint TL between two upper-limb joints with four DNN architectures using sliding windows. We used two feedforward and two recurrent DNN models with feature engineering and feature learning, respectively. We found that the dependencies between sEMG and force are short-term (<400 ms) and that sliding windows are sufficient to capture them, suggesting that more complicated recurrent structures may not be necessary. Also, using DNN architectures reduced the required sliding window length. A model pre-trained on elbow data was fine-tuned on hand–wrist data, improving force estimation accuracy and reducing the required training data amount. A convolutional neural network with a 391 ms sliding window fine-tuned using 20 s of training data had an error of 6.03 ± 0.49% maximum voluntary torque, which is statistically lower than both our multilayer perceptron model with TL and a linear regression model using 40 s of training data. The success of TL between two distinct joints could help enrich the data available for future deep learning-related studies.

Role of joint interactions in upper limb joint movements: a disability simulation study using wearable inertial sensors for 3D motion capture

BackgroundRestriction of movement at a joint due to disease or dysfunction can alter the range of motion (ROM) at other joints due to joint interactions. In this paper, we quantify the extent to which joint restrictions impact upper limb joint movements by conducting a disability simulation study that used wearable inertial sensors for three-dimensional (3D) motion capture.MethodsWe employed the Wearable Inertial Sensors for Exergames (WISE) system for assessing the ROM at the shoulder (flexion–extension, abduction–adduction, and internal–external rotation), elbow (flexion–extension), and forearm (pronation-supination). We recruited 20 healthy individuals to first perform instructed shoulder, elbow, and forearm movements without any external restrictions, and then perform the same movements with restriction braces placed to limit movement at the shoulder, elbow, and forearm, separately, to simulate disability. To quantify the extent to which a restriction at a non-instructed joint affected movement at an instructed joint, we computed average percentage reduction in ROM in the restricted versus unrestricted conditions. Moreover, we performed analysis of variance and post hoc Tukey tests (q statistic) to determine the statistical significance (p < 0.05 denoted using *) of the differences in ROM of an instructed joint in the unrestricted versus restricted conditions.ResultsRestricting movement at the shoulder led to a large reduction in the average ROM for elbow flexion–extension (21.93%, q = 9.34*) and restricting elbow movement significantly reduced the average ROM for shoulder flexion–extension (17.77%, q = 8.05*), shoulder abduction–adduction (19.80%, q = 7.60*), and forearm pronation-supination (14.04%, q = 4.96*). Finally, restricting the forearm significantly reduced the average ROM for shoulder internal–external rotation (16.71%, q = 3.81*) and elbow flexion–extension (10.01%, q = 4.27*).ConclusionsJoint interactions across non-instructed joints can reduce the ROM of instructed movements. Assessment of ROM in the real-world using 3D motion capture, for example using the WISE system, can aid in understanding movement limitations, informing interventions, and monitoring progress with rehabilitation.

Research on the difference of stroke characteristics and stroke effect between different stroke duration of table tennis players

This study aimed to explore the differences in joint kinematic characteristics and stroke effect between fast and slow strokes of table tennis players. Thirty-four table tennis players were randomly selected as participants for this experiment. A high-speed infrared motion capture system was used to collect kinematic data of the right-side upper and lower limb joints during strokes. Simultaneously, a high-speed camera was used to measure the stroke effect. According to the duration of a stroke, the stroke data were classified into two types: fast-stroke and slow-stroke using a two-step clustering algorithm. The duration of the three phases of fast-stroke was shorter, with faster ball speed and stronger spin. Compared with slow-stroke, fast-stroke exhibited shorter displacements in the three lower limb joints and faster linear velocities in the three upper limb joints. In addition, the motion angles of the knee and ankle joints were smaller, while the angles of the hip, shoulder, and elbow joints were larger, with higher angular velocities. Increasing the extension speed of the lower limbs, the flexion speed of the elbow joints, and the wrist movement speed can achieve fast strokes, enhancing ball speed and spin. Small and quick hip joint movement can effectively transfer energy to the upper limbs, increasing the movement speed of the elbow and wrist joints, thus improving the ball speed and spin of the stroke.

Microinstability of Major Joints in Movement Disorders: The Hidden Challenge.

Microinstability, characterized by subtle and often painful disturbances in joint stability, significantly impacts individuals engaged in activities requiring extensive ranges of motion, such as dancing or gymnastics, and is particularly prevalent in young female athletes. This condition, resulting from progressive microtrauma, architectural and functional abnormalities, or iatrogenic factors, is challenging to diagnose and often underreported. Understanding the biomechanical nuances of microinstability is essential for accurate diagnosis and effective management. Upper limb joints, including the shoulder, elbow, wrist, and hand, each exhibit unique anatomical and functional characteristics that contribute to their susceptibility to microinstability. Movement disorders, such as Parkinson's disease, essential tremor, dystonia, and cerebral palsy, exacerbate joint instability due to impaired proprioception, altered muscle tone, and uncoordinated muscle contractions. Effective diagnosis involves physical examination techniques and advanced imaging modalities. Therapeutic interventions encompass physical therapy, pharmacological treatments, surgical procedures, and assistive devices, tailored to enhance joint stability and improve the quality of life for affected individuals.

An Exploration of Self-Efficacy and Its Associated Factors among Rheumatoid Arthritis Patients in Taiwan

Self-efficacy is an important ingredient in successful disease management, especially in patients with chronic conditions such as rheumatoid arthritis (RA). However, the information on self-efficacy and its influencing factors among RA patients is scarce. This study investigated the level of self-efficacy and its pertinent predictors among RA patients in Taiwan. This cross-sectional study recruited patients with RA from a hospital in Taiwan between January and October 2023. A structured questionnaire was used to collect data on respondents’ demographic and job characteristics and included a Chinese version of the Arthritis Self-Efficacy Scale (ASES). Multiple linear stepwise regression analysis was employed to identify predictors of self-efficacy. A total of 284 RA patients were enrolled during the study period. The mean ASES score among enrollees was 1607.1, indicating a moderate level of self-efficacy (score range of 200–2000). The regression model displayed that those with higher disease activity scores, Taiwanese Depression Questionnaire scores, fatigue level, shorter disease duration, swollen upper limb joints, and no regular exercise regimen reported lower ASES scores, accounted for 46% of the total variance. The study findings may be useful for healthcare providers in identifying RA patients with low self-efficacy attitudes, a trait that appears to be linked to several medical indicators, and thus facilitating the provision of future tailored healthcare regimens.

Upper limb joint kinematics resulting from a model conceived for the analysis of SHAP motor tasks performed by trans-radial amputees: discrepancies with the Vicon upper limb model joint kinematics

Upper limb joint kinematics resulting from a model conceived for the analysis of SHAP motor tasks performed by trans-radial amputees: discrepancies with the Vicon upper limb model joint kinematics

Research on design and control methods of a lightweight upper limb joint isokinetic rehabilitation training equipment.

Isokinetic exercise can improve joint muscle strength and stability, making it suitable for early rehabilitation of stroke patients. However, traditional isokinetic equipment is bulky and costly, and cannot effectively avoid external environmental interference. This paper designed a lightweight upper limb joint isokinetic rehabilitation training equipment, with a control system that includes a speed planning strategy and speed control with disturbance rejection. Based on the established human-machine kinematic closed-loop model between the equipment and the user, a dynamic evaluation method of torque at the joint level was proposed. To validate the effectiveness of the equipment, experiments were conducted by manually applying random disturbances to the equipment operated at an isokinetic speed. The results showed that the root mean square error between the observed torque curve of the second-order linear extended state observer used in this paper and the actual disturbance curve was 0.52, and the maximum speed tracking error of the speed control algorithm was 1.27%. In fast and slow sinusoidal speed curve tracking experiments, the root mean square errors of the speed tracking results for this algorithm were 9.65 and 5.27, respectively, while the tracking errors for the PID speed control algorithm under the same environment were 19.94 and 12.11. The research results indicate that compared with traditional PID control method, the proposed control strategy demonstrates superior performance in achieving isokinetic control and suppressing external disturbances, thereby exhibiting significant potential in promoting upper limb rehabilitation among patients.

Variability in musculoskeletal fatigue responses associated with repeated exposure to an occupational overhead drilling task completed on successive days

Emerging research suggests that muscular and kinematic responses to overhead work display a high degree of variability in fatigue-related muscular and kinematics changes, both between and within individuals when evaluated across separate days. This study examined whether electromyographic (EMG), kinematic, and kinetic responses to an overhead drilling task performed until volitional fatigue were comparable to those of a repeated identical exposure of the task completed 1 week later. Surface EMG and intramuscular EMG, sampled from 7 shoulder muscles, and right upper limb kinematics and kinetics were analyzed from 15 male and 14 female participants. No significant day-to-day changes in EMG mean power frequency (MPF) were observed, though serratus anterior displayed significantly less fatigue-related increase in EMG root-mean-squared (RMS) signal amplitude on day 2. Unfatigued upper kinematics on day 2 featured an increase in thoracohumeral elevation, elbow flexion, and decrease in wrist ulnar deviation compared to unfatigued state on day 1. Fatigue-related changes in shoulder joint flexion moment that were present on day 1 were reduced on day 2, suggesting that a more efficient overhead work strategy was learned and preserved across successive days. Day-to-day changes in upper limb joint angle variability, quantified by median absolute deviation (MdAD), were joint dependent. Despite yielding a variable fatigue-related kinetic strategy on both days, kinematic and kinetic fatigue-related changes on a second day of completing an overhead drilling task suggested a potential kinematic learning effect.

Innervation of the human sternoclavicular joint.

The sternoclavicular joint (SCJ) functions as the basal joint of the entire upper limb and must move in the proper pattern for normal scapular motion. Afferent sensations from joints, such as proprioception and pain sensation, are important for maintaining the proper motion and condition of joints. Detailed anatomical data are useful for discussing injuries or surgeries that impair the afferent nerve to the SCJ. Nerve branches to SCJs were examined on 12 sides, and the subclavian nerve was investigated on six sides to clarify whether it innervates this joint. On seven of the 12 sides, the SCJ was innervated by two nerves, (1) a branch from the medial supraclavicular nerve that ran medially along the clavicle and (2) a branch from the lateral pectoral nerve that innervated the clavicular head and upper part of the sternocostal head of the pectoralis major. This branch ran medially behind the clavicular head of the pectoralis major and reached the SCJ. In the remaining five sides, the SCJ was innervated solely by the branch from the medial supraclavicular nerve. Subclavian nerves ended within the subclavius muscle or periosteum of the clavicle and were separate from the SCJs. Our data on the route of nerve branches to the SCJ suggest that injury or surgery, such as clavicle fracture or resection of the clavicular head of the pectoralis major for myocutaneous flap transfer, can impair the SCJ's afferent nerve supply.

A critical review of transitioning from conventional actuators to artificial muscles in upper-limb rehabilitation devices

Brain injuries resulting from spinal cord injuries, strokes, or cerebral palsy are among the traumas most capable of compromising the motor activities of human limbs, hence the necessity for the development of exoskeletons dedicated to the rehabilitation of these organs. This review examines the landscape of actuators essential for the design of cutting-edge upper-limb rehabilitation exoskeletal structures. Beyond merely surveying the current types of actuators available, the paper aims to provide guidelines for selecting actuators that fit optimally with the objectives of upper-limb rehabilitation. The description starts with a brief discussion on the biomechanics of the upper limbs, focusing on the kinematics of pivotal joints (wrist, elbow, shoulder). Subsequently, the existing actuators are systematically reviewed, offering detailed insights into their primary features, operational principles, strengths, weaknesses, and noteworthy applications within the realm of rehabilitation robotics. After the discussion about the actuators, the paper advances by furnishing valuable guidelines for actuators’ selection tailored for upper limb rehabilitation. These guidelines discuss crucial factors, such as the forces required and the natural Range Of Motions (ROMs) of upper limb joints. Finally, the manuscript serves as a valuable resource for researchers, engineers, and practitioners involved in the development of innovative upper-limb rehabilitation devices.

Causal pathways of potential factors affecting participation level of individuals with unilateral cerebral palsy

Introduction: Although most children with unilateral cerebral palsy can achieve independent mobility levels with or without assistive devices, they remain susceptible to decreased participation. This study aimed to explore the potential factors affecting participation of children with unilateral cerebral palsy. Method: Fifty children with unilateral cerebral palsy were enrolled. The degree of spasticity in the upper limb muscles was assessed using the Modified Ashworth Scale, active range of motion of the upper limb joints was assessed using a universal goniometer, and activity performance was measured using the ABILHAND-Kids and Gross Motor Function Measure. Environmental factors and mental health were evaluated using the European Child Environment Questionnaire and Strength and Difficulties Questionnaire. The Child and Adolescent Scale of Participation was used to assess participation. Results: Path analysis showed that upper limb impairment had both direct (β = −0.41; p &lt; 0.05) and indirect (β = 0.64; p &lt; 0.001) effects on participation. Most importantly, it was found that the participation of children with unilateral cerebral palsy was notably influenced by environmental factors and mental health (β2 = −0.42; p &lt; 0.05, and β2 = −0.36; p &lt; 0.05). Conclusion: Participation of children with unilateral cerebral palsy is affected by a combination of functioning and contextual factors.

Wrestling injuries during the 2016 Rio and 2020 Tokyo Olympic Games

ObjectivesTo evaluate and compare the injuries of Olympic wrestlers during the 2016 Rio and 2020 Tokyo Olympic Games held in August 2021 due to the COVID-19 pandemic.MethodsIn this descriptive epidemiological...

Restoration of coherent reach-grasp-pull movement via sequential intraneural peripheral nerve stimulation in rats

Objective. Peripheral nerve stimulation (PNS) has been demonstrated as an effective way to selectively activate muscles and to produce fine hand movements. However, sequential multi-joint upper limb movements, which are critical for paralysis rehabilitation, has not been tested with PNS. Here, we aimed to restore multiple upper limb joint movements through an intraneural interface with a single electrode, achieving coherent reach-grasp-pull movement tasks through sequential stimulation. Approach. A transverse intrafascicular multichannel electrode was implanted under the axilla of the rat’s upper limb, traversing the musculocutaneous, radial, median, and ulnar nerves. Intramuscular electrodes were implanted into the biceps brachii (BB), triceps brachii (TB), flexor carpi radialis (FCR), and extensor carpi radialis (ECR) muscles to record electromyographic (EMG) activity and video recordings were used to capture the kinematics of elbow, wrist, and digit joints. Charge-balanced biphasic pulses were applied to different channels to recruit distinct upper limb muscles, with concurrent recording of EMG signals and joint kinematics to assess the efficacy of the stimulation. Finally, a sequential stimulation protocol was employed by generating coordinated pulses in different channels. Main results. BB, TB, FCR and ECR muscles were selectively activated and various upper limb movements, including elbow flexion, elbow extension, wrist flexion, wrist extension, digit flexion, and digit extension, were reliably generated. The modulation effects of stimulation parameters, including pulse width, amplitude, and frequency, on induced joint movements were investigated and reach-grasp-pull movement was elicited by sequential stimulation. Significance. Our results demonstrated the feasibility of sequential intraneural stimulation for functional multi-joint movement restoration, providing a new approach for clinical rehabilitation in paralyzed patients.

Silajathu Rasayana in Management of Rheumatoid Arthritis

Rheumatoid Arthritis is a systemic autoimmune disease characterized by inflammatory arthritis and extra-articular involvement. Considering the pathophysiology, clinical features, and extra-articular manifestations it can be correlated to Vataraktha in Ayurveda. In this case, a 24-year-old female patient who was diagnosed with Juvenile Rheumatoid Arthritis at the age of 15 and was under Disease-modifying anti-rheumatic drug therapy for several years, complaints of pain and swelling over symmetrical joints of upper and lower limbs along with morning stiffness, and evident boutonniere deformity. She also had pain in her left hip for 4 years. Ayurvedic treatment was initiated with a primary focus on Amapachana, Shodhana, and Rasayana therapies. Patient assessment was conducted using a Visual analog scale, DAS28 score, HAQ-DI score, and Ama assessment tool on the 0th and 69th day. DAS 28 score improved from 7.73 to 3.19, and HAQ-DI score improved from 1.63 to 0.88. The visual analog scale was improved from 8 to 4. Following 69 days of treatment incorporated with Ayurvedic treatment procedures coupled with Rasayana therapy, demonstrated a notable amelioration of symptoms, an enhancement in the overall quality of life, and an improvement in laboratory parameters.

Upper-limb joint kinematics analysis of accuracy dart throwing at different vertical targets between different level dart players

Darts has evolved from a traditional pub room game to a professional sport. More and more people worldwide are participating in the sport of dart throwing. In order to enhance throwing performance, it is important to understand the mechanics of precise dart throwing techniques. Therefore, the purpose of this study was to investigate the fine-tune control of joint kinematics with different vertical targets between different skill levels to understand how to increase the success rate and generate precise fine-tuning of the motor system. Eight advanced players and eight intermediate players participated in this study. A motion capture system measured the kinematic data of the arm during throwing. The results indicated a significant interaction in shoulder internal rotation velocity (p = .031) and elbow supination velocity (p = .047) between advanced and intermediate groups with the different vertical targets. When intermediate players threw darts at different vertical targets, changes in shoulder internal rotation velocity and elbow supination velocity were observed. Conversely, these phenomena were not present in the advanced group. Additionally, we found that dart accuracy or light weight throwing requires an more angle of elbow pronation and generate high angular velocity of wrist palmar flexion during the release process. Based on the findings of this study, these results could provide a reference guide for dart throwing to improve the throwing performance.

Can lower-limb exoskeletons support sit-to-stand motions in frail elderly without crutches? A study combining optimal control and motion capture.

With the global geriatric population expected to reach 1.5 billion by 2050, different assistive technologies have been developed to tackle age-associated movement impairments. Lower-limb robotic exoskeletons have the potential to support frail older adults while promoting activities of daily living, but the need for crutches may be challenging for this population. Crutches aid safety and stability, but moving in an exoskeleton with them can be unnatural to human movements, and coordination can be difficult. Frail older adults may not have the sufficient arm strength to use them, or prolonged usage can lead to upper limb joint deterioration. The research presented in this paper makes a contribution to a more detailed study of crutch-less exoskeleton use, analyzing in particular the most challenging motion, sit-to-stand (STS). It combines motion capture and optimal control approaches to evaluate and compare the STS dynamics with the TWIN exoskeleton with and without crutches. The results show trajectories that are significantly faster than the exoskeleton's default trajectory, and identify the motor torques needed for full and partial STS assistance. With the TWIN exoskeleton's existing motors being able to support 112 Nm (hips) and 88 Nm (knees) total, assuming an ideal contribution from the device and user, the older adult would need to contribute a total of 8 Nm (hips) and 50 Nm (knees). For TWIN to provide full STS assistance, it would require new motors that can exert at least 121 Nm (hips) and 140 Nm (knees) total. The presented optimal control approaches can be replicated on other exoskeletons to determine the torques required with their mass distributions. Future improvements are discussed and the results presented lay groundwork for eliminating crutches when moving with an exoskeleton.

Estimating Rotational Acceleration in Shoulder and Elbow Joints Using a Transformer Algorithm and a Fusion of Biosignals.

In the present study, we used a transformer model and a fusion of biosignals to estimate rotational acceleration in elbow and shoulder joints. To achieve our study objectives, we proposed a mechanomyography (MMG) signal isolation technique based on a variational mode decomposition (VMD) algorithm. Our results show that the VMD algorithm delivered excellent performance in MMG signal extraction compared to the commonly used technique of empirical mode decomposition (EMD). In addition, we found that transformer models delivered estimates of joint acceleration that were more precise than those produced by mainstream time series forecasting models. The average R2 values of transformer are 0.967, 0.968, and 0.935, respectively. Finally, we found that using a fusion of signals resulted in more precise estimation performance compared to using MMG signals alone. The differences between the average R2 values are 0.041, 0.053, and 0.043, respectively. Taken together, the VMD isolation method, the transformer algorithm and the signal fusion technique described in this paper can be seen as supplying a robust framework for estimating rotational acceleration in upper-limb joints. Further study is warranted to examine the effectiveness of this framework in other musculoskeletal contexts.

Anatomical and biomechanical characteristics of plantaris tendon and its application in ligament reconstruction

To improve the clinical utility of the plantaris tendon mainly by summarizing its anatomical characteristics, biomechanical properties, harvesting methods, and its applications in ligament reconstruction. The relevant literature from domestic and international databases regarding the anatomical and biomechanical characteristics of the plantaris tendon and its applications in ligament reconstruction was comprehensively reviewed and systematically summarized. The plantaris tendons have an absence. The majority of plantaris tendon forms a fan-shape on the anterior and medial sides of the Achilles tendon and terminates at the calcaneal tuberosity. There are significant differences in biomechanical parameters between plantaris tendon with different numbers of strands, and multi strand plantaris tendon have significant advantages over single strand tendon. The plantaris tendon can be harvested through proximal and distal approaches, and it is necessary to ensure that there are no obvious anatomical variations or adhesions in the surrounding area before harvesting. The plantaris tendon is commonly utilized in ligament reconstruction around the ankle joint or suture reinforcement for Achilles tendon rupture, with satisfactory effectiveness. There is limited research on the use of plantar tendon in the reconstruction of upper limb and knee joint ligaments. The plantaris tendon is relatively superficial, easy to be harvested, and has less impact on local function. The plantaris tendon is commonly utilized in ligaments reconstruction around the ankle joint or suture reinforcement for Achilles tendon rupture. The study on the plantaris tendon for upper limbs and knee joints ligament reconstruction is rarely and require further research.

Intelligent upper-limb exoskeleton integrated with soft bioelectronics and deep learning for intention-driven augmentation

The age and stroke-associated decline in musculoskeletal strength degrades the ability to perform daily human tasks using the upper extremities. Here, we introduce an intelligent upper-limb exoskeleton system that utilizes deep learning to predict human intention for strength augmentation. The embedded soft wearable sensors provide sensory feedback by collecting real-time muscle activities, which are simultaneously computed to determine the user’s intended movement. Cloud-based deep learning predicts four upper-limb joint motions with an average accuracy of 96.2% at a 500–550 ms response rate, suggesting that the exoskeleton operates just by human intention. In addition, an array of soft pneumatics assists the intended movements by providing 897 newtons of force while generating a displacement of 87 mm at maximum. The intent-driven exoskeleton can reduce human muscle activities by 3.7 times on average compared to the unassisted exoskeleton.

AI-Based Automatic System for Assessing Upper-Limb Spasticity of Patients With Stroke Through Voluntary Movement.

Spasticity is a common complication for patients with stroke, but only few studies investigate the relation between spasticity and voluntary movement. This study proposed a novel automatic system for assessing the severity of spasticity (SS) of four upper-limb joints, including the elbow, wrist, thumb, and fingers, through voluntary movements. A wearable system which combined 19 inertial measurement units and a pressure ball was proposed to collect the kinematic and force information when the participants perform four tasks, namely cone stacking (CS), fast flexion and extension (FFE), slow ball squeezing (SBS), and fast ball squeezing (FBS). Several time and frequency domain features were extracted from the collected data, and two feature selection approaches based on recursive feature elimination were adopted to select the most influential features. The selected features were input into five machine learning techniques for assessing the SS for each joint. The results indicated that using CS task to assess the SS of elbow and fingers and using FBS task to assess the SS of thumb and wrist can reach the highest weighted-average F1-score. Furthermore, the study also concluded that FBS is the optimal task for assessing all the four upper-limb joints. The overall result shown that the proposed automatic system can assess four upper-limb joints through voluntary movements accurately, which is a breakthrough of finding the relation between spasticity and voluntary movement.