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.

Grip and pinch strength prediction models based on hand anthropometric parameters: an analytic cross-sectional study.

BACKGROUND: Hand grip strength (HGS) and pinch strength are important clinical measures for assessing the hand and overall health. OBJECTIVE: The aim of the present study is to predict HGS and pinch strength based on 1 hand anthropometry, and (2) body anthropometric parameters using machine learning. METHODS: A Secondary analysis was conducted on 542 participant aged 30-60 years from the Persian Organizational Cohort study in Mashhad University of Medical Sciences. Artificial Neural Network (ANN) were fitted as prediction model. The dataset was divided into two sets: a training set, which comprised 70% of the data, and a test set, which comprised 30% of the data. Various combinations of the hand anthropometric, demographic, and body anthropometric parameters were used to determine the most accurate model. RESULTS: The optimal HGS model, using the input of gender, body mass, and hand anthropometric parameters of length (both total length and palm), maximum width, maximum breadth, and hand shape index, achieved nearly equal accuracy to the model that incorporated all variables (RMSE = 5.23, Adjusted R2 = 0.67). As for pinch strength, gender, hand length (both total length and palm), maximum width, maximum breadth, hand shape index, hand span, and middle finger length came closest to the model incorporating all variables (RMSE = 1.20, Adjusted R2 = 0.52). CONCLUSION: This ANN model showed that hand anthropometric parameters of total length, palm length, maximum width, maximum breadth, and the hand shape index, emerge as optimal predictors for both HGS and HPS. Body anthropometric factors (e.g., body mass) play roles as predictors for HGS, whereas their influence on pinch strength appears to be less pronounced. LEVEL OF EVIDENCE: Level III (Diagnosis). TRIAL REGISTRATION: Not applicable.

Pressure Sensors for Evaluating Hand Grasp and Pinch.

This study addresses the need for highly sensitive tools to evaluate hand strength, particularly grasp and pinch strength, which are vital for diagnosing and rehabilitating conditions affecting hand function. Current devices like the Jamar dynamometer and Martin Vigorimeter, although reliable, fail to measure extremely low force or pressure values required for individuals with severe hand impairments. This research introduces a novel device, a modified Martin Vigorimeter, utilizing an ultra-soft latex chamber and differential pressure measurement to detect minute pressure changes, thus significantly enhancing sensitivity. The device offers a cost-effective solution, making advanced hand strength evaluation more accessible for clinical and research applications. Future research should validate its accuracy across diverse populations and settings, exploring its broader implications for hand rehabilitation and occupational health.

Are the sensorimotor control capabilities of the hands the factors influencing hand function in people with schizophrenia?

BACKGROUND: Previous works reported people with schizophrenia experienced inferior hand functions which influence their daily participation and work efficiency. Sensorimotor capability is one of indispensable elements acting in a well-executed feed-forward and feedback control loop to contribute to hand performances. However, rare studies investigated contribution of sensorimotor ability to hand functions for people with schizophrenia. This study aimed to explore hand function in people with schizophrenia based on the perspective of the sensorimotor control capabilities of the hands. METHODS: Twenty-seven people at the chronic stage of schizophrenia were enrolled. The following assessment tools were used: the Purdue Pegboard Test (PPT) and the VALPAR Component Work Sample-8 (VCWS 8) system for hand function; the Self-Reported Graphic version of the Personal and Social Performance (SRG-PSP) scale for functionality; and the Semmes-Weinstein Monofilaments (SWM), the pinch-holding-up-activity (PHUA) test and the Manual Tactile Test (MTT) for the sensory and sensorimotor parameters. The Clinical Global Impression-Severity (CGI-S) scale and the Extrapyramidal Symptom Rating Scale (ESRS) were used to grade the severity of the illness and the side-effects of the drugs. Spearman's rank correlation coefficient was used to analyze associations among hand function, functionality, and sensorimotor capabilities. A multiple linear regression analysis was used to identify the determinants of hand function. RESULTS: The results indicated that both hand function and sensorimotor capability were worse in people with schizophrenia than in healthy people, with the exception of the sensory threshold measured with the SWM. Moreover, the sensorimotor abilities of the hands were associated with hand function. The results of the regression analysis showed that the MTT measure of stereognosis was a determinant of the PPT measure of the dominant hand function and of the performance on the VCWS 8, and that the ESRS and the MTT measure of barognosis were determinants of the performance on the assembly task of the PPT. CONCLUSIONS: The findings suggested that sensorimotor capabilities, especially stereognosis and barognosis, are crucial determinants of hand function in people with schizophrenia. The results also revealed that the side effects of drugs and the duration of the illness directly affect hand function. CLINICAL TRAIL REGISTRATION: ClinicalTrials.gov , identifier NCT04941677, 28/06/2021.

Normative values for hand grip and pinch strength for 6 to 18 year-olds in Saudi Arabia.

BACKGROUND: Normative values for hand grip and pinch strength among children in Saudi Arabia has not been well established. Therefore, the main aim of this study is to establish normative values for hand grip and pinch strength in children aged 6 to 18 years in Saudi Arabia. METHODS: A cross-sectional study was conducted from different 5 regions in Saudi Arabia. Participants between the age of 6 years and 18 years old were recruited through different primary and secondary schools in Saudi Arabia. Data for age, gender, Body Mass Index, and preferred hand were collected. Hand grip strength was measured using digital hand dynamometer and the tip pinch, palmar pinch, and key pinch strength were measured using the hydraulic pinch gauge. RESULTS: A total of 616 participants included in this study (318 boys and 298 girls). Participants were stratified into 5 chronological age groups of 6-7 years, 8-9, 10-11, 12-13, 14-15, 16-17, and 18 years. The results showed an overall trend of increasing hand grip strength and pinch strength with age regardless of hand preference. Boys had significantly higher grip strength than girls in all age groups (P < 0.05). CONCLUSION: This study established normative values for hand grip and pinch strength in the healthy Saudi pediatric and adolescent population, using boys and girls aged 6 to 18. The outcomes of this study also demonstrated that gender, age, and hand preference can all have an impact on how strong a handgrip develops.

Head posture mediates the association of cognition with hand grip and pinch strength in older adults: an examination using structural equation modeling.

BACKGROUND: The association of cognition with hand grip and pinch strength has been well-recognized in older adults. The authors sought to explore: (1) associations among forward head posture (FHP), cognition, and hand grip and pinch strength in older adults; and (2) the mediator role of FHP in these pathways using structural equation modeling (SEM). METHODS: This cross-sectional study included 88 older adults (70.5% male; mean age = 68.75±3.87 years). Cognition was assessed by the Mini-Mental State Examination (MMSE), head posture by the Craniovertebral Angle (CVA) obtained from photographic analysis, hand grip strength by a handheld dynamometer, and pinch strength by a pinch meter. Using the two SEMs, a potential mediator role of the CVA was investigated. While the MMSE was addressed as an independent variable in both models, hand grip and pinch strength were addressed as dependent variables in model 1 and model 2, respectively. RESULTS: The correlations between the CVA and MMSE (r = 0.310), hand grip strength (r = 0.370), and pinch strength (r = 0.274 to 0.292) were statistically significant (p < 0.001). In addition, significant associations were found between the MMSE and hand grip and pinch strength, ranging from 0.307 to 0.380 (p < 0.001). The mediation analysis showed that the standardized total (ß = 0.41, p < 0.001) and indirect (mediated) effects (ß = 0.12, p = 0.008) of the MMSE on hand grip strength were significant in model (1) The results were similar for model (2) The standardized total (ß = 0.39, p = 0.001) and indirect effects (ß = 0.10, p = 0.026) of the MMSE on pinch strength were significant. As a partial mediator in both models, the CVA explained 29% and 26% of the total effect in models 1 and 2, respectively. CONCLUSIONS: The CVA was associated with the MMSE, hand grip strength, and pinch strength, and CVA partially mediates the association of the MMSE with grip and pinch strength in older adults, indicating that cognition had an effect on grip and pinch strength through an indirect path via head posture. This finding reveals that evaluating head posture and providing corrective therapeutic interventions as needed may be beneficial in reducing the negative impact of decreased cognition on motor functions in older adults.

Assessment and treatment of nonsurgical thumb carpometacarpal joint osteoarthritis: A modified Delphi-based consensus paper of the American Society of Hand Therapists.

BACKGROUND: While the literature is abundant on hand therapy assessment and treatment of nonsurgical thumb carpometacarpal (CMC) osteoarthritis (OA), clarity and uniformity are meager, making it a desirable diagnosis to establish expert consensus. PURPOSE: This study aimed to ascertain if consensus exists for the assessment and treatment of nonsurgical management of thumb CMC OA in the hand therapy clinical setting. STUDY DESIGN: This was a consensus paper via the modified Delphi approach. METHODS: A modified Delphi method was used to determine consensus among an expert panel, including hand therapists and hand surgeons, via two online surveys. A consensus paper steering committee (from the American Society of Hand Therapist's research division) designed the surveys and analyzed responses. Consensus was established as 75% agreement among the expert panel. Demographic information was collected from the expert panel. RESULTS: The expert panel included 34 hand therapists and seven hand surgeons. The survey response rates were 93.6% for the first survey and 90.2% for the second survey. Consensus recommendations were classified according to the World Health Organization categorization. These included evaluating the body structures for clinical signs/clinical testing and body functions for pain, range of motion for palmar abduction, radial abduction, opposition, and thumb metacarpal phalangeal flexion/extension, and grip and tripod pinch strength. Further consensus recommendations were for the assessment of function using a region-specific, upper extremity patient-reported outcome measure (activity and participation), environmental factors, outcome expectation, and illness perception within the patient's unique environmental and social contexts. Treatment recommendations included the use of an orthosis during painful activities, a dynamic stability program (stable C posture, release of tight adductors, and strengthening of stabilizers), patient education, joint protection techniques, adaptive equipment, and functional-based intervention. CONCLUSIONS: The findings describe the consensus of a group of experts and provide a clinical reference tool on the hand therapy assessment and treatment of nonsurgical thumb CMC joint OA.

Pain, function, and radiographic disease in trapeziometacarpal osteoarthritis.

INTRODUCTION: Trapeziometacarpal joint osteoarthritis (OA) produces significant functional impairment due to pain and loss of strength in both power and precision grips, but few studies have related radiographic scores to functional and pain-based measures. PURPOSE: To investigate the association between markers of radiographic disease and outcomes for symptomatic and functional disease. STUDY DESIGN: This study in an exploratory analysis of baseline data from the first 100 participants in a clinical trial evaluating the efficacy of combined conservative therapies for base of thumb OA (COMBO). METHODS: Functional Index for Hand Osteoarthritis (FIHOA) scores and Visual Analogue Scale (VAS) scores for pain were recorded for the index hand. Bilateral isometric grip and tip-pinch strength measurements were taken, as well as posteroanterior and Eaton stress-view hand radiographs. Generalized estimating equations (GEEs), univariate, and multivariate analyses were used according to whether the data were bilateral or unilateral. RESULTS: A total of 79 females and 21 males were included, with a median Kellgren-Lawrence (KL) grade of 3 in the index hand. Higher KL and Eaton grades were associated with lower grip strength in the GEE analysis (B-coefficients of -1.25 and -1.16, and P-values of .002 and .010, respectively). Higher KL grade was also associated with poorer function and higher pain levels in the multivariable analysis (B-coefficients of 1.029 and 3.681, and P-values of .021 and .047, respectively). Lower radial subluxation ratios were associated with lower grip strength in the GEE analysis, and higher pain scores in the multivariable analysis (B-coefficients of 2.06 and -42.1, and P-values of .006 and .031, respectively). Greater pain scores were also associated with poorer function (B-coefficient 0.082, P-value .001). CONCLUSION: More advanced radiographic trapeziometacarpal OA severity is associated with lower grip strength and poorer self-reported functional outcomes. Lower subluxation ratios were associated with higher pain scores and lower grip strength.

Outcome After Pollicization for Congenital Thumb Deficiency: A Cohort Study of Cases in a Single Unit, 1987 to 2016.

PURPOSE: To investigate the functional and aesthetic outcomes in a cohort with pollicizations performed due to congenital anomalies in our hospital. METHODS: From 1987 to 2016, we performed pollicizations in 32 hands of children aged 1 to 8 years (median, 2 years). We followed-up on 31 of the hands from 1 to 31 years (median, 10 years) after the procedure. The participants and their caregivers self-assessed their function and appearance with visual analogue scales and patient-reported outcome measures (Patient-Reported Outcomes Measurement Information System Pediatric Upper Extremity; the short version of the Disability of Arm, Shoulder and Hand Outcome Measure; and EQ-5D-3L). We examined the hands with regard to motion, strength, sensitivity, and function. RESULTS: There were 2 complications and 6 reoperations. Participants with mild anomalies (radial longitudinal deficiency Bayne type N/0 to 2) had better subjective and objective hand function than participants with severe anomalies (radial longitudinal deficiency Bayne type 3-4, ulnar dimelia, 5-finger hand). Hands with preoperatively near-normal index fingers had, in most cases, good thumb opposition and pinch, and hands in both groups benefited from the creation of a cylinder grip. Grip and pinch strength were lower than reported in cohort studies where an additional opponensplasty had been performed. CONCLUSIONS: Hands with severe congenital anomalies also benefited from the procedure. We recommend a simplified follow-up program to identify cases where additional surgeries to enhance strength should be considered during growth of the child. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Measuring pinch strength before and after haemodialysis session in patients with end stage renal failure.

The objective of the study was to observe the change in Pinch Strength (PS) of arteriovenous fistula (AVF) arm and non-AVF arm before and after haemodialysis (HD). A total of 31 patients (21 Male and 10 Female) undergoing HD during January and February 2020 at a trust hospital were selected through purposive sampling. Mean PS was calculated from the measurements taken using the Jamar digital pinch gauge with an interval of five seconds between each measurement. Paired sample T-test was applied using SPSS 20. The mean PS values for AVF arm when compared before and after the session were 3.64 ±1.01 and 2.87 ±1.20 kgs (p<0.01), whereas for non AVF arm PS values were 3.96 ±1.50 and 3.69 ±1.37 kgs (p=0.09). It was concluded that PS of AVF arm decreased more significantly after HD as compared to the non AVF arm.

Clinical and electrophysiological examination of pinch strength in patients with amyotrophic lateral sclerosis.

BACKGROUND: The split-hand concept has highlighted the preferential wasting of the thenar side of the hand in amyotrophic lateral sclerosis (ALS). Our objective is to re-explore pinch grip strength to assess whether it has the potential to be a practical biomarker of ALS. METHODS: We measured different pinch grip strengths (thumb, index, and fifth) using a pinch gauge from both hands of 54 ALS patients and correlated this with the Medical Research Council (MRC) score, the upper-limb component of the revised ALS Functional Rating Scale - Revised (ALSFRS-R) score, and compound muscle action potentials (CMAPs) that comprise the split-hand index. RESULTS: Pinch grip strength using any of the three fingers showed a positive correlation with its corresponding CMAP, MRC grading, and upper-limb ALSFRS-R score. The thumb pinch showed the strongest correlation with the split-hand index and MRC grading. CONCLUSIONS: Pinch grip strength test using a simple gauge deserves further study as a potentially practical biomarker of ALS.

Relationship between ultrasonographic hand muscle thickness measurements and muscle strength following median or ulnar nerve reconstruction.

INTRODUCTION: The aim of this study was to assess the relationship between ultrasonographic hand muscle thickness measurements and hand muscle strength in patients who underwent median or ulnar nerve reconstruction. METHODS: In this prospective, cross-sectional study, intrinsic hand muscle thicknesses were measured using ultrasound with a 4- to 13-MHz linear-array probe. Measurements of hand strength were performed using a dynamometer and a pinchmeter. RESULTS: In the median nerve group (n = 11), a moderate correlation (r = 0.694; P = .018) was observed between lateral pinch strength and transverse thenar thickness. In the ulnar nerve group (n = 11), longitudinal thenar thickness below the flexor pollicis longus tendon was moderate to highly correlated with pinch and handgrip strengths (r = 0.726-0.893; P < .05); whole transverse thenar thickness was moderate to highly correlated with pinch strengths (r = 0.724-0.836; P < .05). DISCUSSION: Sonographic measurements of intrinsic hand muscle thickness may be a useful tool for the assessment and follow-up of patients with median or ulnar nerve injury.

Test-retest reliability of static and dynamic motor fatigability protocols using grip and pinch strength in typically developing children.

Upper limb motor fatigability is an important debilitating factor for activities of daily living in clinical pediatric populations. However, the reliability of fatigability protocols in these populations is currently unknown. Therefore, the current study investigates test-retest reliability of a static and dynamic motor fatigability protocol for grip and pinch strength in typically developing children (TDC). Eighty-nine TDC (35 boys, 54 girls; mean age 10 years 11 months) used a grip and pinch dynamometer for static (sustained) and dynamic (repeated) contractions during 30s. For static motor fatigability (SFI), mean (Fmean) and SD (Fvar) of force were calculated, and for dynamic motor fatigability, F mean and number of peaks (Npeaks) were calculated. Intraclass correlation coefficients (ICC) were calculated. ICCs of F mean in static and dynamic motor fatigability were high (ICC: 0.94-0.96 and 0.91-0.98). ICCs were moderate to high for F var (ICC: 0.67-0.85). The SFI showed moderate ICCs (ICC: 0.69-0.77). ICCs were moderate to high for N peaks (ICC: 0.78-0.91).Conclusion: The results suggest that static and dynamic motor fatigability in for grip and pinch can be used reliably in TD children aged 6-18 years. What is Known: •Psychometric properties of motor fatigability protocols using grip and pinch in children are lacking. •Motor fatigability in grip and pinch is an important debilitating symptom in multiple neurologic populations. What is New: •Static fatigability can be investigated using a 30-s maximum sustained grip strength protocol in children. •Dynamic fatigability can be investigated using a 30-s maximum repeated grip strength protocol in children.

Effects of Virtual Reality and Task-Oriented Training on Hand Function and Activity Performance in Pediatric Hand Burns: A Randomized Controlled Trial.

OBJECTIVE: To assess the efficacy of a motion-sensing, hands-free gaming device and task-oriented training (TOT) programs on improving hand function, activity performance, and satisfaction in pediatric hand burns. DESIGN: A randomized controlled trial. SETTING: Outpatient rehabilitation center. PARTICIPANTS: Fifty children with deep partial-thickness or full-thickness hand burns. (N=50; mean age, 10.70±1.64y; range, 7-14y) INTERVENTIONS: Children were randomized into 1 of the following 3 groups: the motion-sensing, hands-free gaming device group that used interactive video games plus traditional rehabilitation (TR); the TOT group that used real materials plus TR; and the control group that only received TR, all groups received the interventions 3 days per week for 8 weeks. MAIN OUTCOME MEASURES: We assessed the children at the baseline and after 8 weeks of intervention. The primary outcome measures were the Jebsen-Taylor Hand Function Test, Duruoz Hand Index (DHI), and Canadian Occupational Performance Measure (COPM). The secondary outcome measures were range of motion (ROM) of the digits, grip strength, and pinch strengths (tip, palmer, and lateral pinch). RESULTS: There was a significant increase in all measurements of the motion-sensing, hands-free gaming device and TOT groups compared with that of the control group postintervention (P<.05). There was no significant change in Jebsen-Taylor Hand Function Test, COPM performance, ROM, grip strength, and tip and lateral pinch strengths between the motion-sensing, hands-free gaming device group and TOT group (P>.05), whereas there was a significant increase in DHI, COPM satisfaction, and palmer pinch strength (P<.05) in the motion-sensing, hands-free gaming device group compared with the TOT group postintervention. CONCLUSIONS: The motion-sensing, hands-free gaming device and TOT programs resulted in significant improvement in hand function, activity performance and satisfaction, ROM of the digits, grip strength, and pinch strengths in pediatric hand burns compared with the traditional hand rehabilitation.

Effect of a Novel Perturbation-Based Pinch Task Training on Sensorimotor Performance of Upper Extremity for Patients With Chronic Stroke: A Pilot Randomized Controlled Trial.

OBJECTIVE: To investigate the effects of perturbation-based pinch task training on the sensorimotor performance of the upper extremities of patients with chronic stroke via a novel vibrotactile therapy system. DESIGN: A single-blinded randomized controlled trial. SETTING: A university hospital. PARTICIPANTS: Patients with chronic stroke (N=19) randomly assigned into either an experimental group or a control group completed the study. INTERVENTIONS: In addition to 10 minutes of traditional sensorimotor facilitation, each participant in the experimental group received 20 minutes of perturbation-based pinch task training in each treatment session, and the controls received 20 minutes of task-specific motor training twice a week for 6 weeks. MAIN OUTCOME MEASURES: The scores for the primary outcome, Semmes-Weinstein monofilament (SWM), and those for the secondary outcomes, Fugl-Meyer Assessment (FMA), amount of use, quality of movement (QOM) on the Motor Activity Log (MAL) scale, and box and block test (BBT), were recorded. All outcome measures were recorded at pretreatment, post treatment, and 12-week follow-up. RESULTS: There were statistically significant between-group differences in the training-induced improvements revealed in the SWM results (P=.04) immediately after training and in the BBT results (P=.05) at the 12-week follow-up. The changes in muscle tone and in the QOM, SWM, and BBT scores indicated statistically significant improvements after 12 sessions of treatment for the experimental group. For the control group, a significant statistical improvement was found in the wrist (P<.001) and coordination (P=.01) component of the FMA score. CONCLUSIONS: This study indicated that the perturbation-based pinch task training has beneficial effects on sensory restoration of the affected thumb in patients with chronic stroke.

Analysis of hand-forearm anthropometric components in assessing handgrip and pinch strengths of school-aged children and adolescents: a partial least squares (PLS) approach.

BACKGROUND: The purpose of this study was to examine the influence of hand-forearm anthropometric dimensions on handgrip and pinch strengths among 7-18 years children and adolescents and to investigate the extent to which these variables can be used to predict hand strength. METHODS: Four types of hand strengths including handgrip, tip to tip, key, and three-jaw chuck pinches were measured in 2637 healthy children and adolescents (1391 boys and 1246 girls) aged 7-18 years using standard adjustable Jamar hydraulic hand dynamometer and pinch gauge. A set of 17 hand-forearm anthropometric dimensions were also measured with an accurate digital caliper and tape measure. RESULTS: No significant differences were found between the hand strengths of boys and girls up to the age of 10 years. Gender related differences in handgrip and pinches were observed from the age of 11 years onwards, with boys always being stronger. The dominant hand was stronger than the non-dominant hand (8% for handgrip and by about 10% for all three types of pinches). The strongest correlations were found between the hand length and hand strengths (r > 0.83 for handgrip and three all pinches; p < 0.001, 2-tailed). Based on the partial least squares (PLS) analysis, 8 out of 17 anthropometric indices including hand length, hand circumference, thumb length, index finger length, middle finger length, and forearm length had considerable loadings in the PLS analysis, which together accounted for 46% of the total variance. CONCLUSIONS: These results may be used by health professionals in clinical settings as well as by designers to create ergonomic hand tools.

Diagnostic accuracy of sensory and motor tests for the diagnosis of carpal tunnel syndrome: a systematic review.

BACKGROUND: Carpal tunnel syndrome (CTS) is the most common entrapment mononeuropathy of the upper extremity. The previous systematic review of the diagnostic tests for CTS was outdated. The objective of this study was to compile and appraise the evidence on the accuracy of sensory and motor tests used for the diagnosis of CTS. METHODS: MEDLINE, CINAHL, and Embase databases were searched on January 20, 2020. Studies assessing at least one diagnostic accuracy property of the sensory or motor tests for CTS diagnosis were selected by two independent reviewers. Diagnostic test accuracy extension of the PRISMA guidelines was followed. Risk of bias and applicability concerns were rated using QUADAS-2 tool. Any reported diagnostic accuracy property was summarized. Study characteristics and any information on the accuracy of the sensory and motor tests for CTS diagnosis were extracted. RESULTS: We included sixteen clinical studies, assessing thirteen different sensory or motor tests. The most sensitive test for CTS diagnosis was the Semmes-Weinstein monofilament test (with 3.22 in any radial digit as the normal threshold) with sensitivity from 0.49 to 0.96. The tests with the highest specificity (Sp) were palmar grip strength (Sp = 0.94), pinch grip strength (Sp from 0.78 to 0.95), thenar atrophy (Sp from 0.96 to 1.00), and two-point discrimination (Sp from 0.81 to 0.98). CONCLUSIONS: The evidence was inconclusive on which sensory or motor test for CTS diagnosis had the highest diagnostic accuracy. The results suggest that clinicians should not use a single sensory or motor test when deciding on CTS diagnosis. TRIAL REGISTRATION: PROSPERO CRD42018109031 , on 20 December 2018.

The relationship between smartphone usage duration (using smartphone's ability to monitor screen time) with hand-grip and pinch-grip strength among young people: an observational study.

BACKGROUND: The use of smartphones has become widely popular, especially among young people, for multiple purposes other than communication, including gaming and internet browsing. The hand and wrist weakness is one of the main complications associated with the increased use of smartphones. This weakness occurs due to the repetitive flexion and extension of the wrist, thumb, and fingers, leading to a significant musculoskeletal pathology. Little is known about the relationship between smartphone usage duration (using the phones ability to monitor screen time) and hand-grip, pinch-grip strength. Therefore, the study was aimed to investigate the association between smartphone usage duration and hand-grip, pinch-grip strength among young people. METHODS: One hundred young males volunteered to participate in the study. Participants were briefly examined for height and weight using a portable stadiometer and a digital scale. Hand-grip, pinch-grip strength measurement was performed using a hand-held dynamometer. Smartphones usage duration was obtained from the daily average screen time reported in the last seven days. RESULTS: Mean daily usage of smartphone among the participants was 7.8 ± 2.2. There was a weak significant inverse relationship between smartphone usage duration and hand-grip strength (r=-.22, p = .03) and pinch-grip strength (r=-.28, p = .004). Linear regression revealed that 18.8 % of the variance in hand-grip strength and 20.4 % of the variance in pinch-grip strength was explained by age, and smartphone usage duration, with the addition of BMI only to hand-grip strength (p's < 0.00). CONCLUSIONS: Prolonged use of smartphones was related to weaker hand-grip and pinch-grip. Despite the weak relationship, the study showed that smartphone usage duration might contribute as a factor along with age to hand muscles' strength.

Body composition and weakness of hand grip strength and pinch strength in patients with chronic kidney disease from different ethnic backgrounds.

BACKGROUND: Chronic kidney disease (CKD) patients commonly report muscle weakness and fatigue. Losing muscle mass increases mortality. Accordingly, we aimed to determine the main factors associated with loss of muscle mass and muscle weakness. METHODS: Anthropometric measurements were made in CKD patients attending a specialised clinic, along with hand grip strength (HGS), pinch strength (PS) and body composition (muscle mass and fat mass), using segmental bioimpedance assessment. RESULTS: We reviewed the results of 161 CKD patients; 105 male (65.2%), mean (SD) age 70.3 (15) years, body mass index (BMI) 28.8 (6.7) kg m-2 . In multivariable models, both HGS and PS were independently negatively associated with age [standardised ß (St ß) = 0.35; 95% confidence limits (CL) = -0.32 to -0.14; St ß = 0.38; 95% CL = -0.65 to -0.02; P < 0.001, respectively] and positively with appendicular muscle in the arm tested [St ß = 0.34; 95% CL = 2.5-6.3; St ß = 0.24; 95% CL = 0.17-0.98; P < 0.001 and P = 0.006, respectively]. In addition, HGS was associated with male gender (St ß = 0.19; 95% CL = 0.7-7.5; P = 0.019] and negatively with percentage body fat (St ß = 0.22; 95% CL = -0.36 to -0.07; P = 0.003]. There were 47 (29.2%) Asian patients who had lower total skeletal muscle mass/height ratio and appendicular muscle mass/BMI ratio compared to other ethnicities [9.6 (1.8) versus 10.5 (1.6) kg m-2 , P < 0.01; 0.73 (0.23) versus 0.83 (0.33) m2 ; P < 0.01). CONCLUSIONS: In CKD patients, we found that muscle weakness measured by HGS and PS was associated with increasing age and loss of appendicular muscle mass. HGS was also weaker with increasing fat mass and female gender, whereas PS was weaker in patients of Asian ethnicity.

Exercise interventions in lateral elbow tendinopathy have better outcomes than passive interventions, but the effects are small: a systematic review and meta-analysis of 2123 subjects in 30 trials.

OBJECTIVE: To evaluate the effectiveness of exercise compared with other conservative interventions in the management of lateral elbow tendinopathy (LET) on pain and function. DESIGN: Systematic review and meta-analysis. METHODS: We used the Cochrane risk-of-bias tool 2 for randomised controlled trials (RCTs) to assess risk of bias and the Grading of Recommendations Assessment, Development and Evaluation methodology to grade the certainty of evidence. Self-perceived improvement, pain intensity, pain-free grip strength (PFGS) and elbow disability were used as primary outcome measures. ELIGIBILITY CRITERIA: RCTs assessing the effectiveness of exercise alone or as an additive intervention compared with passive interventions, wait-and-see or injections in patients with LET. RESULTS: 30 RCTs (2123 participants, 5 comparator interventions) were identified. Exercise outperformed (low certainty) corticosteroid injections in all outcomes at all time points except short-term pain reduction. Clinically significant differences were found in PFGS at short-term (mean difference (MD): 12.15, (95% CI) 1.69 to 22.6), mid-term (MD: 22.45, 95% CI 3.63 to 41.3) and long-term follow-up (MD: 18, 95% CI 11.17 to 24.84). Statistically significant differences (very low certainty) for exercise compared with wait-and-see were found only in self-perceived improvement at short-term, pain reduction and elbow disability at short-term and long-term follow-up. Substantial heterogeneity in descriptions of equipment, load, duration and frequency of exercise programmes were evident. CONCLUSIONS: Low and very low certainty evidence suggests exercise is effective compared with passive interventions with or without invasive treatment in LET, but the effect is small. PROSPERO REGISTRATION NUMBER: CRD42018082703.