Relationship Between Grip and Pinch Strength and Activities of Daily Living in Stroke Patients

Associations between pinch strength, cardiovascular events and all-cause mortality in patients undergoing maintenance hemodialysis

BACKGROUND AND AIMS

Patients undergoing maintenance hemodialysis (MHD) experience increased mortality and cardiovascular disease (CVD) risks; however, the potential connection between pinch strength (PS) and the prognosis of these patients remains unknown. Consequently, this study aimed to comprehensively assess the influence of PS and handgrip strength (HGS) on both survival and cardiovascular events (CVE) in patients undergoing MHD.

METHODS

Data were gathered from patients undergoing MHD at the Hemodialysis Center of Guangzhou Red Cross Hospital in March 2021. We performed a retrospective follow-up spanning 24 months, with death serving as the primary endpoint for observation and CVE as the secondary endpoint. Multifactorial Cox regression analysis, Kaplan-Meier survival curves, trend tests, and restricted cubic spline were applied to explore the association.

RESULTS

During a 24-month follow-up, data were collected from 140 patients undergoing MHD with an average age of 66.71 ± 12.61 years. Among them, 52 (37.14%) experienced mortality, whereas 36 (40.00%) had CVE without baseline CVD. Kaplan-Meier survival curves demonstrated better survival rates and reduced CVE risk for patients in the second, third, and fourth quartiles compared with those in the first quartile for PS. Adjusted analyses in different models revealed higher PS levels were independently associated with all-cause mortality (major model, model 4, HR, 0.78; 95% CI, 0.64-0.95) but not with CVE risk (unadjusted HR, 0.90; 95% CI, 0.77-1.05). Compared with lower quartile PS levels, higher PS levels significantly reduced all-cause mortality (HR, 0.31; 95% CI, 0.10-1.02), and this trend remained consistent (P for trend = 0.021). Finally, the restricted cubic spline method using different models showed a linear relationship between PS and all-cause mortality (P > 0.05), when PS exceeded 4.99 kg, the all-cause mortality of MHD patients significantly decreased.

CONCLUSIONS

PS was independently associated with all-cause mortality but not with CVE in patients undergoing MHD.

Combining soft robotics and telerehabilitation for improving motor function after stroke

Telerehabilitation and robotics, either traditional rigid or soft, have been extensively studied and used to improve hand functionality after a stroke. However, a limited number of devices combined these two technologies to such a level of maturity that was possible to use them at the patients' home, unsupervised. Here we present a novel investigation that demonstrates the feasibility of a system that integrates a soft inflatable robotic glove, a cloud-connected software interface, and a telerehabilitation therapy. Ten chronic moderate-to-severe stroke survivors independently used the system at their home for 4 weeks, following a software-led therapy and being in touch with occupational therapists. Data from the therapy, including automatic assessments by the robot, were available to the occupational therapists in real-time, thanks to the cloud-connected capability of the system. The participants used the system intensively (about five times more movements per session than the standard care) for a total of more than 8 hr of therapy on average. We were able to observe improvements in standard clinical metrics (FMA +3.9 ± 4.0, p < .05, COPM-P + 2.5 ± 1.3, p < .05, COPM-S + 2.6 ± 1.9, p < .05, MAL-AOU +6.6 ± 6.5, p < .05) and range of motion (+88%) at the end of the intervention. Despite being small, these improvements sustained at follow-up, 2 weeks after the end of the therapy. These promising results pave the way toward further investigation for the deployment of combined soft robotic/telerehabilitive systems at-home for autonomous usage for stroke rehabilitation.

"Self-care selfies": Patient-uploaded videos capture meaningful changes in dexterity over 6 months

OBJECTIVE

Upper extremity function reflects disease progression in multiple sclerosis (MS). This study evaluated the feasibility, validity, and sensitivity to change of remote dexterity assessments applying human pose estimation to patient-uploaded videos.

METHODS

A discovery cohort of 50 adults with MS recorded "selfie" videos of self-care tasks at home: buttoning, brushing teeth, and eating. Kinematic data were extracted using MediaPipe Hand pose estimation software. Clinical comparison tests were grip and pinch strength, 9 hole peg test (9HPT), and vibration, and patient-reported dexterity assessments (ABILHAND). Feasibility and acceptability were evaluated (Health-ITUES framework). A validation cohort (N = 35) completed 9HPT and videos.

RESULTS

The modality was feasible: 88% of the 50 enrolled participants uploaded ≥3 videos, and 74% completed the study. It was also usable: assessments easy to access (95%), platform easy to use (97%), and tasks representative of daily activities (86%). The buttoning task revealed four metrics with strong correlations with 9HPT (nondominant: r = 0.60-0.69, dominant: r = 0.51-0.57, P < 0.05) and ABILHAND (r = -0.48, P = 0.05). Retest validity at 1 week was stable (r > 0.8). Cross-sectional correlations between video metrics and 9HPT were similar at 6 months, and in the validation cohort (nondominant: r = 0.46, dominant: r = 0.45, P < 0.05). Over 6 months, pinch strength (5.8-5.0 kg/cm2 , P = 0.05) and self-reported pinch (ABILHAND) decreased marginally. While only 15% of participants worsened by 20% on 9HPT, 70% worsened in key buttoning video metrics.

INTERPRETATION

Patient-uploaded videos represent a novel, patient-centered modality for capturing dexterity that appears valid and sensitive to change, enhancing its potential to be disseminated for neurological disease monitoring and treatment.

An evaluation of 3D printable elastics for post stroke dynamic hand bracing: a pilot study

The rise of 3D printing allows unprecedented customization of rehabilitation devices, and with an ever-expanding library of 3D printable (3DP) materials, the spectrum of attenable rehabilitation devices is likewise expanding. The current pilot study explores feasibility of using 3DP elastic materials to create dynamic hand orthoses for stroke survivors. A dynamic orthosis featuring a replaceable finger component was fabricated using 3DP elastic materials. Duplicates of the finger component were printed using different materials ranging from low stiffness (low elastic modulus) to relatively high stiffness (high elastic modulus). Five stroke survivors with predominantly moderate hand impairment were recruited to evaluate usability and impact of orthoses on upper extremity function and biomechanics. No significant differences in usability were found between 3D-printed orthoses and a commercial orthosis. Increases in stiffness of the 3DP material reduced pincer force (p = .0041) and the BBT score (p = .043). In comparison, the commercial orthosis did not reduce pincer force but may reduce BBT score to a degree that is clinically significant (p = .0002). While preliminary, these findings suggest that a dynamic orthosis is a feasible clinical application of 3DP elastic materials, and future study is warranted.

Ultrasound Assessment of Spastic Muscles in Ambulatory Chronic Stroke Survivors Reveals Function-Dependent Changes

OBJECTIVE

To correlate ultrasound characteristics of spastic muscles with clinical and functional measurements in chronic stroke survivors.

METHODS

Ultrasound assessment and clinical and functional assessments were performed in 28 ambulatory stroke survivors (12 females, mean age 57.8 ± 11.8 years, 76 ± 45 months after stroke).

RESULTS

Muscle thickness in the affected side was decreased compared with the contralateral side (p < 0.001). The decrease was more evident in the upper limb muscles. On the affected side, the modified Heckmatt scale score was lowest (closer to normal) in the rectus femoris (RF) muscle compared with other muscles (biceps brachii (BB), flexor carpi ulnaris (FCU) and medial gastrocnemius (MG)). Muscle thickness and echogenicity of spastic muscles did not correlate with spasticity, as measured with the modified Ashworth scale (MAS), Fugl-Meyer motor assessment scores, age, or time since stroke. There was a significant negative correlation between grip strength and percentage decrease in muscle thickness for the spastic FCU muscle (r = -0.49, p = 0.008). RF muscle thickness correlated with ambulatory function (Timed Up and Go test (r = 0.44, p = 0.021) and 6-metre walk test (r = 0.41, p = 0.032)). There was no significant correlation between echogenicity and functional assessments Conclusion: Ambulatory chronic stroke survivors had function-dependent changes in muscle thickness on the affected side. Muscle thickness and echogenicity of spastic muscles did not correlate with spasticity, Fugl-Meyer motor assessment scores, age, or time since stroke.

The Effects of Yoga Exercise on Blood Pressure and Hand Grip Strength in Chronic Stroke Patients: A Pilot Controlled Study

BACKGROUND

We investigated the beneficial effect of add-on yoga with rehabilitation on blood pressure (BP) and hand grip strength in patients with chronic stroke (more than 90 days).

METHODS

The study included patients 30-80 years of age who could stand independently for 1 min. Patients with psychiatric diseases or undergoing other therapies (like acupuncture) were excluded. The yoga group received training (1 h session twice weekly) with standard rehabilitation for 8 weeks. The control group received standard rehabilitation only. There were no differences in age, gender, hand grip strength, or BP between the two groups (16 subjects in each group) at baseline.

RESULTS

The systolic BP (p = 0.01) decreased significantly, and the diastolic BP also decreased but not significantly in the yoga group (p = 0.11). For hand grip strength, both the unaffected hand (p = 0.00025) and the affected hand (p = 0.027) improved significantly. The control group showed no significant change in systolic or diastolic BP, nor did the grip strength change in both hands. Gender and age also affected the results of overall rehabilitation in that women benefited more from a decrease in BP, while men and young people (lower than the mean age of 60) benefited from hand grip strength improvement.

CONCLUSIONS

Combining yoga with rehabilitation in chronic stroke patients can improve hand grip strength and decrease systolic BP.

Development of an Innovative Telerehabilitation System to Improve Handgrip Strength

Handgrip strength is an essential function of the hand to perform day-to-day tasks. People lose grip strength due to various factors such as aging, diseases, and other medical conditions. According to neuroplastic and physiological principles, grip strength can be improved using goal-oriented tasks or exercises repeatedly and consistently. People often fail to adhere to repeated movements, including grip strength exercises. Studies have shown that game-based rehabilitation has improved exercise compliance and functional outcomes. This article explains the design and development of an affordable smartphone-based telerehabilitation system that includes an innovatively designed grip strength device (eGripper) and a phone application to play games.

Does grip strength of the less-affected side of ischemic stroke survivors influences performance of self-care activities?

Background and aim

Adequate grip strength is needed to execute various self-care activities. This study was aimed to assess the influence of grip strength of the less-affected side of ischemic stroke survivors on performance of self-care activities, and also to determine the reference values of less-affected grip strength needed for independent performance of each of the self-care activities.

Methods

Seventy-three consenting patients with ischemic stroke participated in this cross-sectional study. Handheld dynamometer was used to measure grip strength of the less-affected hand, while functional independence measure was used to evaluate self-care activities (eating, grooming, bathing, dressing of upper body, dressing of lower body and toileting) as independent and dependent. Data was analyzed using inferential statistics of Pearson’s correlation, binomial logistic regression, and receiver operating characteristics. Alpha level was set at p < 0.05.

Results

The mean hand grip strength, functional independence measure and trunk control test scores were 23.8 kg, 29.9 kg, and 68.2 kg respectively. Grip strength was significantly associated with independence in all of the self-care activities (p < 0.05). Less-affected grip strength of 19.5 kg (sensitivity, 80.4%; specificity, 80.1%; area under curve, 0.85), 23.7 kg (sensitivity, 79%; specificity, 72.2%; area under curve, 0.79), 24.8 kg (sensitivity, 70.2%; specificity, 65.2%; area under curve, 0.75), 24.7 kg (sensitivity, 82.1%; specificity, 80.1%; area under curve, 0.84), 23.7 kg (sensitivity, 80.1%; specificity, 76.1%; area under curve, 0.84), and 19.9 kg (sensitivity, 76.9%; specificity, 76.2%; area under curve, 0.79) was needed for independent performance in eating, grooming, bathing, dressing of upper body, dressing of lower body, and toileting respectively.

Conclusion

The less-affected grip strength of patients with ischemic stroke influences their ability to independently perform self-care activities. The reference values of less-affected grip strength in association with other stroke-related characteristics may help clinicians to estimate independence in eating, grooming, bathing, dressing of upper body, dressing of lower body, and toileting among patients with ischemic stroke.

Validity and reliability of sensor system to measure trunk range of motion during Streamlined Wolf Motor Function Test in chronic stroke and aged-matched healthy participants

OBJECTIVE

To investigate the validity and reliability of using the Valedo® system to measure trunk Range of Motion (ROM) during performance of the streamlined Wolf Motor Function Test (SWMFT).

METHODS

Twenty chronic strokes and 20 age-matched healthy participants performed SWMFT while wearing Valedo® sensors on their trunks to capture trunk movements. A paired sample T-test was used to examine the validity of the system in distinguishing between the healthy and stroke group, and between the affected and unaffected sides in the stroke group. Interclass correlation coefficients were used to assess the inter-rater and intra-rater reliability (between-days) with 95% CI.

RESULTS

The Valedo® system was able to distinguish between stroke and healthy participants; stroke participants employed greater trunk range of movements than the healthy controls in all tasks (p < .01). Furthermore, the Valedo® system enabled differentiation between affected and unaffected hands of people within the stroke group. The reliability for the stroke group was good to excellent with intrarater reliability (ICC = 0.71-0.92) and interrater reliability (ICC = 0.63-0.95).

CONCLUSIONS

The Valedo system demonstrates an acceptable level of validity and reliability for measuring trunk ROM during the Streamlined Wolf Motor Function Test (SWMFT). Future studies with a larger sample size, different levels of upper limb impairment are warranted.

Evaluation of a shortened version of the Action Research Arm Test (ARAT) for upper extremity function after stroke: The Mini-ARAT

OBJECTIVES

(i) to create a shortened version of the Action Research Arm Test scale, (ii) to investigate its psychometric properties compared to the original scale and (iii) to externally validate it within an independent cohort.

DESIGN

Prospective longitudinal cohort study.

SETTINGS

Two University Hospitals (France, Switzerland).

PARTICIPANTS

47 patients with poststroke motor deficits of the upper limb coming from two different sites were included and divided into two cohorts (n = 22 for the construction cohort; n = 25 for the validation cohort).

MAIN MEASURES

We used the first cohort to build the Mini-ARAT by shortening the Action Research Arm Test scale on the basis of ceiling/floor effects and collinearity of the subscales. We studied its reliability, validity, and responsiveness and performed an external validation with the second cohort.

RESULTS

The Mini-ARAT consisted of 2 subscales from the original Action Research Arm Test scale (Grip and Pinch). Internal consistency (α = 87) and inter-rater reliability (0.99, 95% CI: 0.98-0.99, p < 0.01) were good and similar to those of the Action Research Arm Test scale. The Minimal Clinically Important Difference of the Mini-ARAT was 9 points. The predictive validity in the construction and validation cohorts showed good correlation between the Mini-ARAT at baseline and the Fugl Meyer at 3 months (rho, 95% CI: 0.77, 0.49-0.90, p < 0.01, and 0.58, 0.19-0.96, p < 0.01).

CONCLUSION

The Mini-ARAT is a time-effective tool able to capture the dynamics of motor deficits with high reliability and consistency, providing excellent information about residual motor functions, which is critically important for clinical and research purposes.

Is grip strength useful in screening to predict the severity of locomotive syndrome?

BACKGROUND

This study was conducted to investigate the relationship between grip strength and the 25-question Geriatric Locomotive Function Scale (GLFS-25) score and the diagnosis of locomotive syndrome (LS), and the usefulness of grip strength in screening for LS.

METHODS

This cross-sectional study was conducted on 2251 community-dwelling residents (male, n = 1035; female, n = 1216). Subjects with GLFS-25 scores of 0-6 points, 7-15 points, 16-23 points, and 24-100 points were diagnosed with non-LS, LS-1, LS-2, and LS-3, respectively. Multivariate linear regression and multivariate logistic regression analyses were performed to assess the relationship between grip strength and the GLFS-25 score and LS after adjustment for age, sex, and body mass index. A conventional receiver operating characteristic (ROC) curve analysis was used to calculate the optimal cutoff value of grip strength for predicting the severity of LS. The discriminative ability of the model was assessed using the area under the ROC curve (AUC).

RESULTS

The multivariate linear regression analysis showed that grip strength was significantly associated with the GLFS-25 score. The multivariate logistic regression analysis revealed that grip strength was significantly associated with the diagnosis of LS. The optimal cutoff values of grip strength for identifying LS-1 or more, LS-2 or more, and LS-3 or more were 36.0 kg (sensitivity 65.7%, specificity 57.1%, AUC 0.66), 35.0 kg (sensitivity 70.0%, specificity 57.5%, AUC 0.70), and 34.0 kg (sensitivity 67.2%, specificity 62.5%, AUC 0.70), respectively, in males, and 24.0 kg (sensitivity 69.1%, specificity 45.4%, AUC 0.61), 23.0 kg (sensitivity 69.5%, specificity 52.3%, AUC 0.67), and 22.0 kg (sensitivity 69.1%, specificity 61.0%, AUC 0.69) in females.

CONCLUSIONS

The use of grip strength in screening to predict the severity of LS may not be clinically useful. However, the results will increase our understanding of the relationship between grip strength and the GLFS-25 scores and LS.

Improving Assessment of Disease Severity and Strategies for Monitoring Progression in Degenerative Cervical Myelopathy [AO Spine RECODE-DCM Research Priority Number 4]

STUDY DESIGN

Narrative Review.

OBJECTIVE

To (i) discuss why assessment and monitoring of disease progression is critical in Degenerative cervical myelopathy (DCM); (ii) outline the important features of an ideal assessment tool and (iii) discuss current and novel strategies for detecting subtle deterioration in DCM.

METHODS

Literature review.

RESULTS

Degenerative cervical myelopathy is an overarching term used to describe progressive injury to the cervical spinal cord by age-related changes of the spinal axis. Based on a study by Smith et al (2020), the prevalence of DCM is approximately 2.3% and is expected to rise as the global population ages. Given the global impact of this disease, it is essential to address important knowledge gaps and prioritize areas for future investigation. As part of the AO Spine RECODE-DCM (Research Objectives and Common Data Elements for Degenerative Cervical Myelopathy) project, a priority setting partnership was initiated to increase research efficiency by identifying the top ten research priorities for DCM. One of the top ten priorities for future DCM research was: What assessment tools can be used to evaluate functional impairment, disability and quality of life in people with DCM? What instruments, tools or methods can be used or developed to monitor people with DCM for disease progression or improvement either before or after surgical treatment?

CONCLUSIONS

With the increasing prevalence of DCM, effective surveillance of this population will require both the implementation of a monitoring framework as well as the development of new assessment tools.

Upper extremity motor abilities and cognitive capability mediate the causal dependency between somatosensory capability and daily function in stroke individuals

Stroke individuals’ daily function has been demonstrated to be influenced by their somatosensory capability, cognitive capability, and upper extremity (UE) motor abilities. However, the structural relationships among these abilities on stroke individuals’ independence in daily function remain unclear. We analyzed the pretest measures of 153 stroke individuals in outpatient rehabilitation settings by structural equation modeling to determine the structural relationship among somatosensory capability, UE muscle strength, UE motor function, and cognitive capability that influences independence in daily function. The standardized results indicated somatosensory capability negatively influenced UE muscle strength, but positively influenced UE muscle strength mediated by UE motor function. UE muscle strength, then, positively influenced individuals’ independence in daily function. On the other hand, somatosensory capability positively influenced cognitive capability, which marginally and positively affected the performance of independence in daily function. To the best of our knowledge, this is the first study to demonstrate the influence of somatosensory capability on the daily function is mediated mainly by motor functions and marginally by cognitive capability. This structural model may allow future clinical therapists to design more effective task-related training protocols to promote the independence in daily function for stroke individuals.

Validity of the modified sphygmomanometer test for the assessment of tip pinch strength in Parkinson's disease

BACKGROUND

The tip pinch is one of the most delicate and precise movement of the hand, and it is used to manipulate small objects, commonly observed in the activities of daily living of any individuals. Individuals with Parkinson Disease (PD) with impaired manual dexterity, manipulative skills, and hand weakness have an important barrier for activities of daily life. However, the dynamometer usually used for measuring the tip pinch have a high cost, so, validate a sphygmomanometer can make this assessment more accessible.

OBJECTIVE

To investigate the validity of the modified sphygmomanometer test in the evaluation of tip pinch strength when compared to the gold standard.

METHODS

50 individuals with idiopathic PD took part in the study. The muscle strength of tip pinch on the dominant and non-dominant side was measured by the modified sphygmomanometer test and the gold standard, the dynamometer. Concurrent validity was analyzed using Pearson's correlation coefficient.

RESULTS

50 individuals diagnosed with idiopathic PD, mean age of 67 ± 8.0 years, 68% male, mean time of diagnosis in months of 84 ± 66 and Hoehn and Yahr mean of 2.5 ± 0.6. There was a significant correlation of moderate magnitude between the modified sphygmomanometer test and the dynamometer in dominant side (r = 0.44; p < 0.01) and non-dominant side (r = 0.48; p < 0.01).

CONCLUSION

The modified sphygmomanometer test showed adequate validity for assessing the muscle strength of the tip pinch in individuals with PD.

Influence of aging, disease, exercise, and injury on human hand movements: A systematic review

The human hand is a versatile organ that performs a variety of activities in daily life. The coordination of digits allows them to deal with objects of various sizes and shapes with an appropriate range of motions (ROM). A systematic literature review was performed to identify the clinical and non-clinical factors which affected the normal ROM, grip strength (GS), and dexterity of hand. The overall outcomes of the systematic review showed that: the performance of the individual declined as the age progressed; the performance of the dominant hand (DH) of an individual was better compared to his/her non-dominant hand (NDH); the tasks performed by a healthy hand was more efficient compared to a diseased one; appropriate rehabilitation programs/exercise techniques after a disease or injury improved the ROM, GS, and dexterity of hand post-surgery on par to a healthy hand.

Anthropometric scaling of musculoskeletal models of the hand captures age-dependent differences in lateral pinch force

Musculoskeletal models and computer simulations enable non-invasive study of muscle function and contact forces. Hand models are useful for understanding the complexities of hand strength, precision movement, and the dexterity required during daily activities. Yet, generic models fail to accurately represent the entire scope of the population, while subject-specific models are labor-intensive to create. The objective of this study was to assess the efficacy of scaled generic models to represent the broad spectrum of strength profiles across the lifespan. We examined one hundred lateral pinch simulations using a generic model of the wrist and thumb anthropometrically scaled to represent the full range of heights reported for four ages across childhood, puberty, older adolescence, and adulthood. We evaluated maximum lateral pinch force produced, muscle control strategies, and the effect of linearly scaling the maximum isometric force. Our simulations demonstrated three main concepts. First, anthropometric scaling could capture age-dependent differences in pinch strength. Second, a generic muscle control strategy is not representative of all populations. Lastly, simulations do not employ optimal fiber length to complete a lateral pinch task. These results demonstrate the potential of anthropometrically-scaled models to study hand strength across the lifespan, while also highlighting that muscle control strategies may adapt as we age. The results also provide insight to the force-length relationship of thumb muscles during lateral pinch. We conclude that anthropometric scaling can accurately represent age characteristics of the population, but subject-specific models are still necessary to represent individuals.

A TRIZ-driven conceptualisation of finger grip enhancer designs for the elderly

Background: Elderly people with severe finger weakness may need assistive health technology interventions. Finger weakness impedes the elderly in executing activities of daily living such as unbuttoning shirts and opening clothes pegs. While studies have related finger weakness with ageing effects, there appears to be no research that uses an algorithmic problem-solving approach such as the theory of inventive problem-solving (TRIZ) to recommend finger grip assistive technologies that resolve the issue of finger weakness among the elderly. Using TRIZ, this study aims to conceptualise finger grip enhancer designs for elderly people. Methods: Several TRIZ tools such as the cause-and-effect chain (CEC) analysis, engineering contradiction, physical contradiction, and substance-field analysis are used to conceptualise solutions that assist elderly people in their day-to-day pinching activities. Results: Based on the segmentation principle, a finger assistant concept powered by a miniature linear actuator is recommended. Specific product development processes are used to further conceptualise the actuation system. The study concluded that the chosen concept should use a DC motor to actuate fingers through tendon cables triggered by a push start button. Conclusions: Finger pinch degradation worsens the quality of life of the elderly. A finger grip enhancer that assists in day-to-day activities may be an effective option for elderly people, not only for their physical but also their mental well-being in society.

Flexion-extension strength of the index-thumb system in Italian population. A cross-sectional study to gather normative data

STUDY DESIGN

Cross-sectional study.

INTRODUCTION

Flexion (Palmar Pinch, PP-MVC and Tip Pinch, TP-MVC) and extension (E-MVC) maximal voluntary contraction (MVC) of the index-thumb system offers a quick way to estimate the level of hands' impairment in several musculoskeletal and neurologic conditions.

PURPOSE OF THE STUDY

This study established normative data of PP-MVC, TP-MVC, E-MVC in the Italian population and evaluated their correlation with hand dominance, anthropometric factors, dexterity and workload level.

METHODS

In our study, 303 healthy people (150F, 153M) were recruited. Participants performed PP-MVC, TP-MVC and E-MVC tests per hand, conducted by using a pinch-gauge. T-test was used to analyze MVC means between sexes and between hands. One-way ANOVA was conducted to compare MVC means in male and female samples stratified by age (18-29, 30-44, 45-59, 60-74, +75). Spearman's correlation analysis was performed to determine anthropometric variables, dexterity and workload level effects on MVCs.

RESULTS

Medium-to-large effect sizes of age were shown in the majority of tasks. The 30 to 44 years and then +75 years age groups showed the highest and the lowest values, respectively, for both sex and both hands. Men were meanly 50% stronger, and the dominant hand showed higher values (6-10%). MVC-tests correlated moderately with weight and height weakly with dexterity and workload level.

CONCLUSIONS

After 30 to 44 years, hand strength declines in line with the normal process of aging that also entails muscle fibers and the reduction of daily activities in older adults. In relative terms, E-MVC showed the highest strength loss in the over 75 seconds. The difference between sexes was higher in E-MVC than in flexion MVCs. E-MVC seems to depend more on musculoskeletal architecture that differs from women to men, according to the highest correlation between E-MVC and anthropometric variables. Only high workload levels impacted hand strength. In heaviest occupations, no PP-MVCs differences were observed between hands.

Effects of a Soft Robotic Hand for Hand Rehabilitation in Chronic Stroke Survivors

OBJECTIVES

Soft robotic hands are proposed for stroke rehabilitation in terms of their high compliance and low inherent stiffness. We investigated the clinical efficacy of a soft robotic hand that could actively flex and extend the fingers in chronic stroke subjects with different levels of spasticity.

METHODS

Sixteen chronic stroke subjects were recruited into this single-group study. Subjects underwent 20 sessions of 1-hour EMG-driven soft robotic hand training. Training effect was evaluated by the pre-training and post-training assessments with the clinical scores: Action Research Arm Test(ARAT), Fugl-Meyer Assessment for Upper Extremity(FMA-UE), Box-and-Block test(BBT), Modified Ashworth Scale(MAS), and maximum voluntary grip strength.

RESULTS

For all the recruited subjects (n = 16), significant improvement of upper limb function was generally observed in ARAT (increased mean=2.44, P = 0.032), FMA-UE (increased mean=3.31, P = 0.003), BBT (increased mean=1.81, P = 0.024), and maximum voluntary grip strength (increased mean=2.14 kg, P < 0.001). No significant change was observed in terms of spasticity with the MAS (decreased mean=0.11, P = 0.423). Further analysis showed subjects with mild or no finger flexor spasticity (MAS<2, n = 9) at pre-training had significant improvement of upper limb function after 20 sessions of training. However, for subjects with moderate and severe finger flexor spasticity (MAS=2,3, n = 7) at pre-training, no significant change in clinical scores was shown and only maximum voluntary grip strength had significant increase.

CONCLUSION

EMG-driven rehabilitation training using the soft robotic hand with flexion and extension could be effective for the functional recovery of upper limb in chronic stroke subjects with mild or no spasticity.

Development of a Comprehensive Outcome Measure for Motor Coordination, Step 2: Reliability and Construct Validity in Chronic Stroke Patients

BACKGROUND

A comprehensive scale assessing motor coordination of multiple body segments was developed using a 3-phase content validation process. The Comprehensive Coordination Scale (CCS) evaluates motor coordination defined as the ability to produce context-dependent movements of multiple effectors in both spatial and temporal domains. The scale assesses motor coordination in individuals with neurological injuries at 2 levels of movement description: the motor performance level describes end point movements (ie, hand, foot), and the movement quality level describes limb joints/trunk movements contributing to end point movement.

OBJECTIVE

To determine measurement properties of the scale in people with chronic stroke.

METHODS

Standardized approaches determined the internal consistency (factor loadings), intrarater and interrater reliability (interclass correlation coefficient), measurement error (SEM; minimal detectable change [MDC]), construct validity, and interpretability (ie, ceiling and floor effects) of the CCS.

RESULTS

Data from 30 patients with chronic stroke were used for the analysis. The internal consistency of the scale was high (0.94), and the scale consisted of separate factors characterizing end point motor performance and movement quality. Intrarater (intraclass correlation coefficient [ICC] = 0.97-0.97) and interrater (ICC=0.76-0.98) reliability of the whole scale and subscales were good to excellent. The CCS had an SEM of 1.80 points (total score = 69 points) and an MDC₉₅ of 4.98 points. The CCS total score was related to Fugl-Meyer Assessment total and motor scores and had no ceiling or floor effects.

CONCLUSIONS

The CCS scale has strong measurement properties and may be a useful measure of spatial and temporal coordination deficits in chronic stroke survivors.

Composite Grip Strength as a Marker of Outcome in Patients Surgically Treated for Degenerative Cervical Myelopathy

Study Design

Retrospective case series.

Purpose

This study aimed to examine the efficacy of composite grip strength as a marker of surgical outcome in patients with moderate to severe degenerative cervical myelopathy.

Overview of Literature

Degenerative cervical myelopathy causes loss of dexterity, muscle strength, and sensations in the hand. The impact of surgical management on improvement in composite grip strength has received scant attention.

Methods

This retrospective study was performed on degenerative cervical myelopathy patients with a complete composite grip strength assessment between January 2013 to January 2019. The Biometrics E-link hand kit was used for the assessment. The following parameters were measured: maximum grip strength, sustained grip strength, three-jaw pinch, maximum key pinch, and sustained key pinch. The pre- and postoperative functional status was assessed using the Nurick grade and the modified Japanese Orthopaedic Association (mJOA) score.

Results

A total of 40 patients were included in the study. The mean patient age was 51.9 years. The mean preoperative Nurick grade was 3.5 and the mJOA score was 10.9. The anterior approach was used in 25 patients, and the posterior approach was used in 15 patients. Four patients developed complications. Degenerative cervical myelopathy resulted in decreased handgrip and pinch strength as compared to normative Indian data. There was a significant improvement in the postoperative composite grip strength for all five parameters. There was no differential improvement between the anterior and posterior surgical groups. The improvement in the composite grip strength correlated with the improvement in functional scores.

Conclusions

Composite grip strength analysis is an objective method for assessing the impact of degenerative cervical myelopathy on grip strength and monitoring the postoperative improvement. Decompressive surgery resulted in global improvement in all the parameters of composite grip strength.

Post-stroke depression, anxiety, and stress symptoms and their associated factors: A cross-sectional study

Individuals post-stroke are subject to increased levels of mental health symptoms. This is a cross-sectional study explored levels of depression, anxiety, and stress symptoms and identified their predictors among Jordanian individuals with stroke. Outcome measures included Depression Anxiety Stress Scale, Fugl-Meyer assessment, goniometry, hand-held dynamometry, nine-hole peg test, Ashworth scale, Motor Activity Log, ten-meter walk test, and 12-item Short-Form health survey (SF-12). Descriptive analyses were used to describe prevalence of mental health symptoms and multiple variable linear regression models were used to identify their predictors. A total of 153 individuals participated in the study. Proportions of participants with mental health symptoms were 74.5% for depression, 52.9% for anxiety, and 68% for stress. Significant predictors of post-stroke mental health symptoms were SF-12 Mental Composite Score and grip strength for depression, anxiety, and stress. Depression and stress symptoms were significantly associated with discontinuation of rehabilitation services. Furthermore, self-reports of fewer sleep hours was significantly associated with anxiety and stress. Finally, Gender and self-reported physical diseases other than stroke were significantly associated with depression symptoms. We conclude that high proportions of Jordanian individuals' post-stroke have suffered mental health symptoms. Future studies are required to design effective interventions to improve post-stroke mental health.

Transcranial direct-current stimulation combined with attention increases cortical excitability and improves motor learning in healthy volunteers

Background

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that has the potential to induce motor cortical plasticity in humans. It is well known that motor cortical plasticity plays an essential role in motor learning and recovery in patients with stroke and neurodegenerative disorders. However, it remains unclear how cognitive function influences motor cortical plasticity induced by tDCS. The present study aimed to investigate whether anodal tDCS combined with attention to a target muscle could enhance motor cortical plasticity and improve motor learning in healthy individuals.

Methods

Thirty-three healthy volunteers were assigned to two experiments. In experiment 1, there were three interventional conditions: 1) anodal tDCS was applied while participants paid attention to the first dorsal interosseous (FDI) muscle, 2) anodal tDCS was applied while participants paid attention to the sound, and 3) anodal tDCS was applied without the participants paying attention to the FDI muscle or the sound. Anodal tDCS (2 mA, 10 min) was applied over the primary motor cortex (M1). Changes in motor evoked potentials (MEPs), short-interval intracortical inhibition (SICI), and intracortical facilitation (ICF) were assessed before and immediately after (0 min), and then 10 min, 30 min, and 60 min after each intervention. In experiment 2, we investigated whether the combination of anodal tDCS and attention to the abductor pollicis brevis (APB) muscle could facilitate the learning of a ballistic thumb movement.

Results

Anodal tDCS increased cortical excitability in all conditions immediately after the stimulation. Significant increases in MEPs and significant decreases in SICI were observed for at least 60 min after anodal tDCS, but only when participants paid attention to the FDI muscle. In contrast, no significant changes in ICF were observed in any condition. In experiment 2, the combination of tDCS and attention to the APB muscle significantly enhanced the acquisition of a ballistic thumb movement. The higher performance was still observed 7 days after the stimulation.

Conclusions

This study shows that anodal tDCS over M1 in conjunction with attention to the target muscle enhances motor cortex plasticity and improves motor learning in healthy adults. These findings suggest that a combination of attention and tDCS may be an effective strategy to promote rehabilitation training in patients with stroke and neurodegenerative disorders.

Trial registration

Retrospectively registered (UMIN000036848).

Hand strengthening exercises in chronic stroke patients: Dose-response evaluation using electromyography

STUDY DESIGN

Cross-sectional.

PURPOSE OF THE STUDY

This study evaluates finger flexion and extension strengthening exercises using elastic resistance in chronic stroke patients.

METHODS

Eighteen stroke patients (mean age: 56.8 ± 7.6 years) with hemiparesis performed 3 consecutive repetitions of finger flexion and extension, using 3 different elastic resistance levels (easy, moderate, and hard). Surface electromyography was recorded from the flexor digitorum superficialis (FDS) and extensor digitorum (ED) muscles and normalized to the maximal electromyography of the non-paretic arm.

RESULTS

Maximal grip strength was 39.2 (standard deviation: 12.5) and 7.8 kg (standard deviation: 9.4) in the nonparetic and paretic hand, respectively. For the paretic hand, muscle activity was higher during finger flexion exercise than during finger extension exercise for both ED (30% [95% confidence interval {CI}: 19-40] vs 15% [95% CI: 5-25] and FDS (37% [95% CI: 27-48] vs 24% [95% CI: 13-35]). For the musculature of both the FDS and ED, no dose-response association was observed for resistance and muscle activity during the flexion exercise (P > .05).

CONCLUSION

The finger flexion exercise showed higher muscle activity in both the flexor and extensor musculature of the forearm than the finger extension exercise. Furthermore, greater resistance did not result in higher muscle activity during the finger flexion exercise. The present results suggest that the finger flexion exercise should be the preferred strengthening exercise to achieve high levels of muscle activity in both flexor and extensor forearm muscles in chronic stroke patients. The finger extension exercise may be performed with emphasis on improving neuromuscular control.

LEVEL OF EVIDENCE

4b.

Prevalence of peripheral neuropathy and its impact on activities of daily living in people with type 2 diabetes mellitus

Myanmar has one of the highest rates of diabetes in South-East Asia. This study aimed to determine prevalence and background characteristics of diabetic peripheral neuropathy and neuropathic pain, their effect on the functioning of hands and feet, and the impact on activities of daily living in people with type 2 diabetes mellitus. A total of 975 participants attending the outpatient clinics of four hospitals in Myanmar were interviewed using questionnaires in the local language about pain and difficulties in daily activities. The participants also underwent tests of physical functioning of both hands and feet. There was a high prevalence rate of neuropathy (33.7%) and neuropathic pain (59.5%), with an increased risk in old age, longer duration of diabetes, and history of smoking. The common difficulties in daily activities were sleeping, climbing stairs, walking, and work or chores. Participants with diabetic neuropathic pain experienced more difficulties in specific activities using upper and lower extremities than did those without. Healthcare service in Myanmar should be focused on diabetic peripheral neuropathy, as it can lead to further disabilities.

Functional and cognitive variables predicting successful use of chopsticks or a spoon by the paretic upper extremity in patients following stroke: a cross-sectional study

BACKGROUND

The factors necessary for successful use of chopsticks or a spoon, by patients with a paretic upper extremity (UE) following stroke are unknown.

OBJECTIVES

We identified the functional capacities and interactions related to chopsticks or spoon use in patients with right hemiplegia following stroke.

METHODS

Participants were 139 stroke patients with right hemiplegia who required rehabilitation, divided into the following three categories: able to use chopsticks, able to use a spoon, or unable to use a spoon. We collected sociodemographic data, medical data, physical and cognitive function data, and functional grades associated with chopsticks or spoon use by the paretic dominant UE while eating. We identified a complex interaction of variables relating to functional use of chopsticks or a spoon using a classification and regression tree analytic process.

RESULTS

Patients with UE Brunnstrom recovery stage (BRS) >IV, and a Hasegawa Dementia Scale - Revised (HDS-R) score >16 had a 91.3% probability of being able to use chopsticks. Moreover, patients with a UE BRS of >IV, and the HDS-R score ≤16 had a 66.7% probability of being able to use a spoon. By contrast, patients with a UE BRS of ≤IV had a 90.5% probability of not being able to use a spoon.

CONCLUSIONS

The interaction of BRS as a measure of UE function and HDS-R score as a measure of cognitive function affect the ability of patients with stroke histories to functionally use the paretic UE to operate chopsticks or a spoon.

External biomechanical constraints impair maximal voluntary grip force stability post-stroke

BACKGROUND

Grip strength is frequently measured as a global indicator of motor function. In clinical populations, such as hemiparesis post-stroke, grip strength is associated with upper-extremity motor impairment, function, and ability to execute activities of daily living. However, biomechanical configuration of the distal arm and hand may influence the magnitude and stability of maximal voluntary grip force and varies across studies. The influence of distal arm/hand biomechanical configuration on grip force remains unclear. Here we investigated how biomechanical configuration of the distal arm/hand influence the magnitude and trial-to-trial variability of maximal grip force performed in similar positions with variations in external constraint.

METHODS

We studied three groups of 20 individuals: healthy young, healthy older, and individuals post-stroke. We tested maximal voluntary grip force in 4 conditions: 1: self-determined/"free"; 2: standard; 3: fixed arm-rest; 4: gripper fixed to arm-rest, using an instrumented grip dynamometer in both dominant/non-dominant and non-paretic/paretic hands.

FINDINGS

Regardless of hand or group, maximal voluntary grip force was highest when the distal limb was most constrained (i.e., Condition 4), followed by the least constrained (i.e., Condition 1) (Cohen's f = 0.52, P's < 0.001). Coefficient of variation among three trials was greater in the paretic hand compared with healthy individuals, particularly in more (Conditions 3 and 4) compared to less (Conditions 1 and 2) constrained conditions (Cohen's f = 0.29, P's < 0.05).

INTERPRETATION

These findings have important implications for design of rehabilitation interventions and devices. Particularly in individuals post-stroke, external biomechanical constraints increase maximal voluntary grip force variability while fewer biomechanical constraints yield more stable performance.

Pilot Study Combining Electrical Stimulation and a Dynamic Hand Orthosis for Functional Recovery in Chronic Stroke

OBJECTIVE

We investigated the effect of a combined neuromuscular electrical stimulation (ES) and dynamic hand orthosis (DHO) regimen with a group of people with chronic stroke to improve performance on specific daily tasks.

METHOD

Four people with chronic stroke participated in an ES-DHO regimen using the affected upper extremity 5×/wk for 6 wk. Outcome measures included grip strength, range of motion (ROM), and analysis of muscle activation-deactivation during release of grasp through electromyography. Ability to perform specific daily living tasks was assessed using the Assessment of Motor and Process Skills (AMPS).

RESULTS

Results suggested that improvements in strength, ROM, and grasp deactivation are possible with the combined ES-DHO regimen. All participants' AMPS motor scores improved.

CONCLUSIONS

An ES-DHO regimen may improve motor skills needed for functional task performance in people with chronic stroke. Results should be interpreted cautiously because of the pilot nature of the study and the small sample size.

Neurobehavioral testing in subarachnoid hemorrhage: A review of methods and current findings in rodents

The most important aspect of a preclinical study seeking to develop a novel therapy for neurological diseases is whether the therapy produces any clinically relevant functional recovery. For this purpose, neurobehavioral tests are commonly used to evaluate the neuroprotective efficacy of treatments in a wide array of cerebrovascular diseases and neurotrauma. Their use, however, has been limited in experimental subarachnoid hemorrhage studies. After several randomized, double-blinded, controlled clinical trials repeatedly failed to produce a benefit in functional outcome despite some improvement in angiographic vasospasm, more rigorous methods of neurobehavioral testing became critical to provide a more comprehensive evaluation of the functional efficacy of proposed treatments. While several subarachnoid hemorrhage studies have incorporated an array of neurobehavioral assays, a standardized methodology has not been agreed upon. Here, we review neurobehavioral tests for rodents and their potential application to subarachnoid hemorrhage studies. Developing a standardized neurobehavioral testing regimen in rodent studies of subarachnoid hemorrhage would allow for better comparison of results between laboratories and a better prediction of what interventions would produce functional benefits in humans.

Perceived ability to perform daily hand activities after stroke and associated factors: a cross-sectional study

Background

Despite that disability of the upper extremity is common after stroke, there is limited knowledge how it influences self-perceived ability to perform daily hand activities. The aim of this study was to describe which daily hand activities that persons with mild to moderate impairments of the upper extremity after stroke perceive difficult to perform and to evaluate how several potential factors are associated with the self-perceived performance.

Methods

Seventy-five persons (72 % male) with mild to moderate impairments of the upper extremity after stroke (4 to 116 months) participated. Self-perceived ability to perform daily hand activities was rated with the ABILHAND Questionnaire. The perceived ability to perform daily hand activities and the potentially associated factors (age, gender, social and vocational situation, affected hand, upper extremity pain, spasticity, grip strength, somatosensation of the hand, manual dexterity, perceived participation and life satisfaction) were evaluated by linear regression models.

Results

The activities that were perceived difficult or impossible for a majority of the participants were bimanual tasks that required fine manual dexterity of the more affected hand. The factor that had the strongest association with perceived ability to perform daily hand activities was dexterity (p < 0.001), which together with perceived participation (p = 0.002) explained 48 % of the variance in the final multivariate model.

Conclusion

Persons with mild to moderate impairments of the upper extremity after stroke perceive that bimanual activities requiring fine manual dexterity are the most difficult to perform. Dexterity and perceived participation are factors specifically important to consider in the rehabilitation of the upper extremity after stroke in order to improve the ability to use the hands in daily life.