Dexterous Hand Research Articles

Combined Effects of Brunnstorm Movement Therapy and Low-Level Laser Therapy on Upper Limb Function and Hand Dexterity in Chronic Stroke Patient

Background: Stroke remains a leading cause of disability worldwide, necessitating innovative rehabilitation strategies to enhance recovery and improve quality of life. The integration of Brunnstrom movement therapy and low-level laser therapy (LLLT) presents a novel approach to addressing the complexities of stroke rehabilitation, focusing on improving upper limb function and hand dexterity. Objective: This study aimed to evaluate the combined effects of Brunnstrom movement therapy and LLLT on upper limb function and hand dexterity in chronic stroke patients, providing insights into potentially enhancing rehabilitation outcomes. Methods: A randomized controlled trial was conducted involving 48 chronic stroke patients, divided equally into two groups to receive either Brunnstrom movement therapy or LLLT. The study spanned six months, with assessments including the Modified Ashworth Scale (MAS), Nine-Hole Peg Test, Box and Block Test, Fugl-Meyer Assessment, and Handheld Dynamometer. Data were analyzed using SPSS version 25, employing descriptive statistics, chi-square tests, and Mann-Whitney U tests to compare outcomes between groups. Results: Significant improvements were noted in both groups, with the LLLT group showing superior performance in the Nine-Hole Peg Test (p<0.001), Box and Block Test (p<0.001), and Fugl-Meyer Assessment (p<0.001) compared to baseline. The MAS scores indicated a significant reduction in muscle spasticity over time in both groups, with the LLLT group exhibiting a more substantial decrease (p=0.003 at week 6). Conclusion: The study demonstrated that combining Brunnstrom movement therapy with LLLT could significantly enhance upper limb function and hand dexterity in chronic stroke patients. These findings advocate for the integration of innovative and non-invasive therapies into rehabilitation programs, potentially setting a new benchmark in stroke recovery practices.

Evaluation of the efficacy of inter-dental brush and dental floss for peri-implant mucositis: A crossover randomized clinical trial.

To evaluate the most effective method for mechanical inter-dental plaque removal between inter-dental brushes (IDB) and dental floss (DF), in addition to toothbrushing in patients affected by peri-implant mucositis (PIM); to identify possible factors related to the patient or to the single implant-supported element that could influence plaque accumulation and inflammation of peri-implant tissues. Forty patients with PIM were recruited. They were randomly assigned to two different groups depending on inter-dental device used (IDB or DF). At baseline (T0), interproximal area (IA), interproximal emergence angle of the implant crown (A°) and manual dexterity (evaluated with Purdue Pegboard) have been recorded. At 14 days (T1), the inter-dental cleaning devices have been inverted between groups. After 14 days (T2), the Plaque Index (PI) and Gingival Index (GI) have been recorded. A questionnaire has been submitted to a patient for the analysis of preferences at T0, T1 and T2. Both inter-dental cleaning devices were effective in reducing PI and GI in the inter-dental area after 14 days of use. GI reduction was influenced by manual dexterity of the dominant hand. No significant differences were found for PI and GI at the variation of IA and A°. IDB was the most effective method for inter-dental plaque removal in all subjects regardless of their manual dexterity. DF seems to be more effective than IDB only in subjects with good dexterity.

Effects of the powerball® system on muscle strength, coordination, fatigue, functionality and quality of life in people with multiple sclerosis. A randomized clinical trial

IntroductionAlthough clinical and functional impairments in the lower limbs have been extensively studied in patients with MS, the upper limb (UL) are also frequently affected. Clinical impairment of the UL in patients with MS is very common with muscle strength and hand dexterity as critical factors in maintaining functional activities that are the basis for independence and quality of life in people with MS.ObjectiveTo investigate the effects of a training protocol using the Powerball® system in combination with conventional physiotherapy on muscle strength, coordination, fatigue, functionality, and quality of life in persons with MS over an 8-week period.Materials and methodsA double-blind randomized controlled trial was conducted. The control group received conventional treatment, while the experimental group received additional UL training using the Powerball® system. Both groups received the same number of sessions and weeks of intervention. The following outcome measures were used: isometric grip and pinch strength, Box and Block Test (BBT), Nine Hole Peg Test (NHPT), Abilhand scale, Fatigue Severity Scale (FSS), Multiple Sclerosis Impact Scale (MSIS-29), and Likert satisfaction questionnaire for the experimental group. All measures were administered at baseline, after the treatment, and during a 3-week follow-up period.Results25 patients completed the study (12 in the experimental and 13 in the control group). The experimental group showed significant improvements in coordination and manual dexterity of the more affected UL as measured by the BBT comparing pre- to post-treatment (p = 0.048) and pre-treatment to follow-up (p = 0.001), and on the less affected UP comparing pre-treatment to follow-up (p < 0.001) and post-treatment to follow-up (p = 0.034). The Likert-type satisfaction questionnaire obtained a mean score of 89.10 (± 8.54) out of 100 points.ConclusionsUpper limb treatment protocol using the Powerball® system, in combination with conventional physiotherapy for 8 weeks resulted in significant improvements in the intra-group analysis for UL coordination and manual dexterity in favor of the experimental group. The experimental group showed excellent satisfaction to the treatment.

Transcutaneous Magnet Localizer for a Self-Contained Myokinetic Prosthetic Hand.

The search for a physiologically appropriate interface for the control of dexterous hand prostheses is an ongoing challenge in bioengineering. In this context, we proposed an interface, named myokinetic control interface, based on the localization of magnets implanted in the residual limb muscles, to monitor their contractions and send appropriate commands to the artificial hand. As part of such concept, this interface requires a transcutaneous magnet localizer that can be integrated in a self-contained limb prosthesis, a feature yet to be realized within the current state of the art. In an attempt to cover this gap, here we present a modular embedded system consisting of a computation unit able to acquire synchronized samples captured by up to eight acquisition units, so to localize multiple magnets. The system exhibits short computation times (<60ms) and power consumption (0.6-1.2W) which are suitable for use in a clinically viable prosthetic arm. The system proved able to localize magnets while moving at speeds in the range of physiological movements (<0.24m/s), with high accuracy (<1mm) and precision (<0.5mm). We demonstrated a system suitable for the implementation of a self-contained myokinetic prosthetic hand. These results pave the way towards the clinical implementation of the myokinetic interface, with amputees controlling an artificial arm by means of implanted magnets.

인지적 지시수행을 결합한 치유농업프로그램이 발달장애인의 손 민첩성, 협응력, 일상생활활동에 미치는 영향(무작위표본추출)

인지적 지시수행을 결합한 치유농업프로그램이 발달장애인의 손 민첩성, 협응력, 일상생활활동에 미치는 영향(무작위표본추출)

Impact of motor task conditions on end-point kinematics and trunk movements during goal-directed arm reach

Task conditions significantly impact human motor control. We investigated how task type, difficulty, and constraints influence the kinematics of goal-directed arm reaching. Non-disabled young adults performed two distinct goal-directed arm reaching tasks: pointing and picking up an object with chopsticks. These tasks were carried out under various conditions, including constrained and unconstrained elbow extension and two different task difficulties. We collected kinematic data using a 3-D motion capture system and analyzed the effects of different task conditions on kinematic variables using linear mixed-effects regression analysis. Our findings revealed statistically significant differences in kinematics between the two tasks. Arm reaching during the picking-up task was slower and exhibited jerkier movements compared to the pointing task. Additionally, when arm reaching was performed with constrained elbow extension, it led to slower and jerkier movements, with an increased involvement of trunk movements compared to the unconstrained condition. These findings show that complex manipulative motor tasks requiring higher hand dexterity necessitate feedback-based control of arm reaching, but simple pointing tasks requiring less hand dexterity do not. In conclusion, our study sheds light on the influence of task conditions on goal-directed arm reaching kinematics and provides valuable insights into the motor control strategies involved in different tasks.

Evolution, biomechanics, and neurobiology converge to explain selective finger motor control.

Humans use their fingers to perform a variety of tasks, from simple grasping to manipulating objects, to typing and playing musical instruments, a variety wider than any other species. The more sophisticated the task, the more it involves individuated finger movements, those in which one or more selected fingers perform an intended action while the motion of other digits is constrained. Here we review the neurobiology of such individuated finger movements. We consider their evolutionary origins, the extent to which finger movements are in fact individuated, and the evolved features of neuromuscular control that both enable and limit individuation. We go on to discuss other features of motor control that combine with individuation to create dexterity, the impairment of individuation by disease, and the broad extent of capabilities that individuation confers on humans. We comment on the challenges facing the development of a truly dexterous bionic hand. We conclude by identifying topics for future investigation that will advance our understanding of how neural networks interact across multiple regions of the central nervous system to create individuated movements for the skills humans use to express their cognitive activity.

Anthropomorphic Soft Hand: Dexterity, Sensing, and Machine Learning

Humans possess dexterous hands that surpass those of other animals, enabling them to perform intricate, complex movements. Soft hands, known for their inherent flexibility, aim to replicate the functionality of human hands. This article provides an overview of the development processes and key directions in soft hand evolution. Starting from basic multi-finger grippers, these hands have made significant advancements in the field of robotics. By mimicking the shape, structure, and functionality of human hands, soft hands can partially replicate human-like movements, offering adaptability and operability during grasping tasks. In addition to mimicking human hand structure, advancements in flexible sensor technology enable soft hands to exhibit touch and perceptual capabilities similar to humans, enhancing their performance in complex tasks. Furthermore, integrating machine learning techniques has significantly promoted the advancement of soft hands, making it possible for them to intelligently adapt to a variety of environments and tasks. It is anticipated that these soft hands, designed to mimic human dexterity, will become a focal point in robotic hand development. They hold significant application potential for industrial flexible gripping solutions, medical rehabilitation, household services, and other domains, offering broad market prospects.

Impact of Hand Grip Strength on Functional Independence and Arm Motor Performance in Stroke Survivors

Background: Stroke remains a leading cause of disability worldwide, with a significant number of survivors experiencing impairments in upper limb function and hand grip strength, which are crucial for performing activities of daily living (ADLs). Understanding the relationship between hand grip strength, functional independence, and arm motor performance is essential for optimizing rehabilitation strategies. Objective: This study aimed to investigate the impact of hand grip strength on functional independence and arm motor performance in stroke survivors and to evaluate the effectiveness of Mirror Therapy in enhancing these outcomes. Methods: An analytical cross-sectional study was conducted at DHQ Teaching Hospital Sargodha, involving 22 stroke survivors, evenly split between genders. Participants were aged 45-65 years, clinically diagnosed with ischemic stroke in the subacute stage, and exhibited Modified Ashworth Scale scores of 1 to 1+ for hand flexors. The study employed randomized assignments to intervention groups, utilizing assessments such as the Action Research Arm Test (ARAT), Fugl-Meyer Assessment for Upper Extremity (FMA UE), Hand-Held Dynamometer (HHD), and Stroke Impact Scale (SIS) at baseline, 3 weeks, and 6 weeks. Statistical analysis was performed using Pearson’s coefficient of correlation with SPSS version 25. Results: Significant improvements were observed in upper limb strength and hand dexterity, particularly in the group undergoing Mirror Therapy. The correlation coefficients among ARAT, HHD, and SIS were .676**, .748**, and .704** respectively, indicating strong positive relationships between hand grip strength, functional ability, and quality of life. Mirror Therapy demonstrated notable enhancements in ARAT (p = .001), FMA UE (p &lt; .000), HHD (p = .000), and SIS scores (p = .000), reflecting increased functional ability, grip strength, and improved quality of life. Conclusion: The study confirmed the significant impact of hand grip strength on the functional independence and arm motor performance of stroke survivors, with Mirror Therapy providing substantial benefits. These findings advocate for the inclusion of grip strength-focused interventions and Mirror Therapy in stroke rehabilitation programs to improve survivors' functional outcomes and quality of life.

Optimal variable state estimation of Dexterous Hand Master system via Kalman filter to control desing in space states

This research aims to design an estimator via Kalman Filter design to estimate the system state variables Dexterous Hand Master, since in practice these are not available for measurement. The Kalman filter problem composes stage of the robust control LQG method, thus it can be stated that uncertainties, noises and disturbances in the system are considered in the controller project. Regarding the performance evaluation method of the controller, it was used the analysis in the time domain to an input to the ramp unit, analyzing settling time and steady-state error. In general, the estimator by Kalman filter designed accomplished his goal in the estimation of states, performing satisfactorily in accordance with the illustrations shown.

Combining Transcranial Direct Current Stimulation With Hand Robotic Rehabilitation in Chronic Stroke Patients: A Double-Blind Randomized Clinical Trial.

This study aimed to assess the impact of combining transcranial direct current stimulation with end-effector robot-assisted treatment on upper limb function, spasticity, and hand dexterity in chronic stroke patients. This was a prospective, double-blind randomized trial with 20 equally allocated stroke patients. The experimental group received dual transcranial direct current stimulation (anode over affected M1, cathode over contralateral M1) alongside robot-assisted treatment, while the control group received sham transcranial direct current stimulation with the same electrode placement + robot-assisted treatment. Each patient underwent 20 combined transcranial direct current stimulation and robot-assisted treatment sessions. The primary outcome measure was the Fugl-Meyer Upper Limb motor score, with secondary outcomes including AMADEO kinematic measures, Action Research Arm Test, and Functional Independence Measure. Assessments were conducted at baseline, after rehabilitation, and 3 mos later. Combining bilateral transcranial direct current stimulation with robot-assisted treatment did not yield additional improvements in Fugl-Meyer Upper Limb motor score, Functional Independence Measure, or Action Research Arm Test scores among stroke patients. However, the real transcranial direct current stimulation group showed enhanced finger flexion in the affected hand based on AMADEO kinematic measures. The addition of transcranial direct current stimulation to robot-assisted treatment did not result in significant overall functional improvements in chronic stroke patients. However, a benefit was observed in finger flexion of the affected hand.

InterCap: Joint Markerless 3D Tracking of Humans and Objects in Interaction from Multi-view RGB-D Images

Humans constantly interact with objects to accomplish tasks. To understand such interactions, computers need to reconstruct these in 3D from images of whole bodies manipulating objects, e.g., for grasping, moving and using the latter. This involves key challenges, such as occlusion between the body and objects, motion blur, depth ambiguities, and the low image resolution of hands and graspable object parts. To make the problem tractable, the community has followed a divide-and-conquer approach, focusing either only on interacting hands, ignoring the body, or on interacting bodies, ignoring the hands. However, these are only parts of the problem. On the contrary, recent work focuses on the whole problem. The GRAB dataset addresses whole-body interaction with dexterous hands but captures motion via markers and lacks video, while the BEHAVE dataset captures video of body-object interaction but lacks hand detail. We address the limitations of prior work with InterCap, a novel method that reconstructs interacting whole-bodies and objects from multi-view RGB-D data, using the parametric whole-body SMPL-X model and known object meshes. To tackle the above challenges, InterCap uses two key observations: (i) Contact between the body and object can be used to improve the pose estimation of both. (ii) Consumer-level Azure Kinect cameras let us set up a simple and flexible multi-view RGB-D system for reducing occlusions, with spatially calibrated and temporally synchronized cameras. With our InterCap method we capture the InterCap dataset, which contains 10 subjects (5 males and 5 females) interacting with 10 daily objects of various sizes and affordances, including contact with the hands or feet. To this end, we introduce a new data-driven hand motion prior, as well as explore simple ways for automatic contact detection based on 2D and 3D cues. In total, InterCap has 223 RGB-D videos, resulting in 67,357 multi-view frames, each containing 6 RGB-D images, paired with pseudo ground-truth 3D body and object meshes. Our InterCap method and dataset fill an important gap in the literature and support many research directions. Data and code are available at https://intercap.is.tue.mpg.de.

Exploring Footedness, Throwing Arm, and Handedness as Predictors of Eyedness Using Cluster Analysis and Machine Learning: Implications for the Origins of Behavioural Asymmetries

Behavioural asymmetries displayed by individuals, such as hand preference and foot preference, tend to be lateralized in the same direction (left or right). This may be because their co-ordination conveys functional benefits for a variety of motor behaviours. To explore the potential functional relationship between key motor asymmetries, we examined whether footedness, handedness, or throwing arm was the strongest predictor of eyedness. Behavioural asymmetries were measured by self-report in 578 left-handed and 612 right-handed individuals. Cluster analysis of the asymmetries revealed four handedness groups: consistent right-handers, left-eyed right-handers, consistent left-handers, and inconsistent left-handers (who were left-handed but right-lateralized for footedness, throwing and eyedness). Supervised machine learning models showed the importance of footedness, in addition to handedness, in determining eyedness. In right-handers, handedness was the best predictor of eyedness, followed closely by footedness, and for left-handers it was footedness. Overall, predictors were more informative in predicting eyedness for individuals with consistent lateral preferences. Implications of the findings in relation to the origins and genetics of handedness and sports training are discussed. Findings are related to fighting theories of handedness and to bipedalism, which evolved after manual dexterity, and which may have led to some humans being right-lateralized for ballistic movements and left-lateralized for hand dexterity.

Development of a 2-DoFs Actuated Wrist for Enhancing the Dexterity of Myoelectric Hands

Development of a 2-DoFs Actuated Wrist for Enhancing the Dexterity of Myoelectric Hands

DeltaHands: A Synergistic Dexterous Hand Framework Based on Delta Robots

DeltaHands: A Synergistic Dexterous Hand Framework Based on Delta Robots

Grasping characteristics of SMA bionic flexible dexterous hand

In order to achieve the mechanical performance of grasping objects with SMA bionic flexible hands, a tendon finite element modeling method is proposed in this article to meet the mechanical requirements of the tendon being subjected to only axial forces and not radial forces. By using finite element dynamic simulation and experimental testing methods, the mechanical characteristics of the SMA bionic hands during the grasping process are analyzed and validated. A finite element dynamic simulation model of the SMA bionic hand grasping process is established to study the overall stress characteristics and contact forces of each phalanx, revealing the grasping characteristics of the bionic hand under SMA driving conditions. By creating a physical prototype of the SMA bionic hand, grasping of different objects is achieved. The results show that the stress in the grasping state of the bionic hand does not exceed 21 MPa, the sum of contact forces is 22 N, the theoretical grasping force is 13 N, and the prototype can grasp objects within a diameter range of 70 mm.

Arthroscopy-Assisted Surgery for Trapeziometacarpal Osteoarthritis.

Background: Functional outcomes of patients who underwent arthroscopy-assisted surgery for trapeziometacarpal osteoarthritis were reported. Methods: We included 24 consecutive patients (6 males and 18 females) who underwent surgery and postoperative hand therapy at our hospital between April 2012 and March 2018. For functional evaluation, we used the Purdue Pegboard Test (PPT), grip and pinch strength, range of motion of the thumb, visual analogue scale (VAS) for thumb pain, Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) and Japanese version of the Patient-Rated Wrist Evaluation (PRWE-J) preoperatively and 3 months postoperatively. Results: The mean PPT rating improved from 12.3 to 13.3, the VAS score from 51 to 16, the QuickDASH score from 48 to 30 and the PRWE-J score from 55 to 29. All the improvements were statistically significant. There was a moderate positive correlation between the magnitude of improvement in PPT and QuickDASH scores. Conclusions: Arthroscopic intervention and associated hand therapy were effective in achieving early postoperative relief of thumb pain and in improving hand dexterity and activities of daily living. Level of Evidence: Level IV (Therapeutic).

Utilizing Music Therapy for Enhanced Recovery from Neurologic Disease Complications

Neurologic music therapy (NMT) has proven instrumental in aiding recovery from complications in patients with a diverse range of neurologic diseases. Integrating music and virtual reality with standard rehabilitation therapies enhances patient compliance and makes therapy more enjoyable. The act of listening to music not only reduces epileptiform discharges but also amplifies brain plasticity. Moreover, music induces discernible variations in brain anatomy between musicians and non-musicians. As a cost-effective intervention, music therapy significantly contributes to the accelerated and efficient recovery of post-stroke patients, particularly when applied promptly after the event. Substantial evidence supports the integration of music into rehabilitation programs, facilitating the recovery of hand function, dexterity, spatial movement, cognitive function, mood, coordination, stride length, and memory. Techniques such as learning words as lyrics, melodic intonation therapy, and singing play crucial roles in expediting recovery for aphasic patients. Recognized by the World Rehabilitation Federation, NMT therapists are valuable members of the rehabilitation team. The approval of NMT as an effective, evidence-based treatment method underscores its significance in enhancing patient outcomes.

Comparison of hand dexterity and hand laterality task in duchenne muscular dystrophy patients with typically developing peers.

Hand dexterity is important with Duchenne muscular dystrophy (DMD). The aim of this study was to compare hand dexterity and hand laterality task assessments in patients with DMD with typically-developing peers. The study included 25 DMD with a mean age of 10.2±2.38 and 21 typically-developing peers with a mean age of 10.33±2.26. Functional levels of DMD patients were determined by Brooke Upper Extremity Functional Classification Scale and Brooke Lower Extremity Functional Scale. The ABILHAND-Kids and 9-hole peg test were used to assess the hand dexterity of all participants, and assess the hand laterality task. Patients with DMD had lower ABILHAND-Kids scores than their typically-developing peers (p < 0.001). Patients with DMD had higher 9-hole peg test duration on the dominant and non-dominant extremity compared to typically-developing peers (p < 0.001). Patients with DMD were found to be different from their typically-developing peers (p < 0.001) in lateralization response time and accuracy. Patients with DMD were found to have lower manual dexterity and hand laterality task skills compared to their typically-developing peers. It is recommended that hand dexterity and upper extremity recognition capacities should be considered in assessment and intervention programs for physiotherapists and clinicians working in this field.

Effectiveness of MusicGlove on Motor and Psychological Symptoms in Parkinson’s Disease: A Quasi-experimental Study

Introduction: Individuals with Parkinson’s Disease commonly experience both physical and psychological effects, which subsequently affect their ability to perform daily activities and overall wellbeing. MusicGlove is an emerging adjunct proposed to address the motor issues but also the psychological ones with references to improving motivation and participation in individuals with Parkinson’s Disease. Aim: To determine the effectiveness of the MusicGlove on hand dexterity and the psychological response in individuals with Parkinson’s disease. Materials and Methods: A quasi-experimental study was performed on 40 individuals with Parkinson disease January 2021 to June 2021 from local community settings in Chengalpattu district, Tamil Nadu, India. They were recruited and divided into a control group (n=20) and experimental group (n=20). Hand dexterity and psychological responses were assessed using the Box and Block Test (BBT), Beck’s Depression Inventory (BDI), and Apathy Inventory (AI) as pre and post-test measures. Both groups received conventional occupational therapy for three weeks in total, and in addition to this, the experimental group received the MusicGlove. The control group included muscle stretching and strengthening activities with therapeutic putty and using activities such as connecting circles where the subject is given a sheet of paper with 25 circles, each containing 25 numbers or letters. They were asked to connect these in ascending, alternating numerical, and alphabetical order. Sessions were conducted for 30 minutes with two sets of repetitions. Descriptive statistics were used to examine data using the Statistical Package for Social Sciences (SPSS) version 24.0. Results: The study results revealed that there was no statistically significant difference found between the groups but clinically significant differences were found between the groups with posttest scores on motor symptoms that were measured by BBT: μ=- 1.2534, p=0.211 (BBT Dominant); μ=-0.9400, p-value=0.3472 (BBT Non Dominant), and psychological symptoms that were measured by BDI; (μ=-1.0445, p-value=0.2983) and AI; (μ=- 1.0445, p-value=0.9203). Conclusion: The study concluded that conventional occupational therapy along with MusicGlove was effective in improving hand dexterity and psychological responses in Parkinson’s disease patients. Also, further study needs to be conducted to warrant its long-term impact of intervention on hand dexterity and psychological responses.