The reliability of a Biometrics device as a tool for assessing hand grip and pinch strength, in a Polish cohort-A prospective observational study.

The aim of the study was to assess the external and internal compatibility of the Biometrics E-LINK EP9 evaluation system device in the area of hand grip and pinch strength in the Polish population. The testing of hand grip and pinch strength was carried out among 122 healthy students. Two examiners performed hand grip and pinch strength measurements with a Biometrics E-LINK EP9 evaluation system device. Measurements were made for the right and left hands. The same people were tested again two weeks later, under the same conditions. The scores of one rater on the first and second tests were compared for reproducibility, and the scores of the two raters were compared to assess the reliability of the instrument. The measurements were found to be highly consistent both between the investigators and between the tests in the hand grip dynamometer test. The findings show high values of the Pearson's correlation coefficient equal or close to 1, as well as the interclass correlation coefficient (ICC) >0.9. Analysis of pinch strength measurements performed using the pinchmeter also found high values of the Pearson's correlation coefficient close to 1, as well as the interclass correlation coefficient >0.9; this reflects high agreement between the measurements performed by two investigators as well as assessments performed by one investigator at time intervals. These findings were confirmed by analyses performed using Bland-Altman plots. The measurements made with the Biometrics E-link EP9 evaluation system show high internal and external consistency in hand grip and pinch strength assessment. Biometrics E-link EP9 can be recommended for daily clinical practice.

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.

Carpal tunnel syndrome prediction with machine learning algorithms using anthropometric and strength-based measurement.

OBJECTIVES: Carpal tunnel syndrome (CTS) stands as the most prevalent upper extremity entrapment neuropathy, with a multifaceted etiology encompassing various risk factors. This study aimed to investigate whether anthropometric measurements of the hand, grip strength, and pinch strength could serve as predictive indicators for CTS through machine learning techniques. METHODS: Enrollment encompassed patients exhibiting CTS symptoms (n = 56) and asymptomatic healthy controls (n = 56), with confirmation via electrophysiological assessments. Anthropometric measurements of the hand were obtained using a digital caliper, grip strength was gauged via a digital handgrip dynamometer, and pinch strengths were assessed using a pinchmeter. A comprehensive analysis was conducted employing four most common and effective machine learning algorithms, integrating thorough parameter tuning and cross-validation procedures. Additionally, the outcomes of variable importance were presented. RESULTS: Among the diverse algorithms, Random Forests (accuracy of 89.474%, F1-score of 0.905, and kappa value of 0.789) and XGBoost (accuracy of 86.842%, F1-score of 0.878, and kappa value of 0.736) emerged as the top-performing choices based on distinct classification metrics. In addition, using variable importance calculations specific to these models, the most important variables were found to be wrist circumference, hand width, hand grip strength, tip pinch, key pinch, and middle finger length. CONCLUSION: The findings of this study demonstrated that wrist circumference, hand width, hand grip strength, tip pinch, key pinch, and middle finger length can be utilized as reliable indicators of CTS. Also, the model developed herein, along with the identified crucial variables, could serve as an informative guide for healthcare professionals, enhancing precision and efficacy in CTS prediction.

Exploratory analysis using machine learning algorithms to predict pinch strength by anthropometric and socio-demographic features.

Objectives. This study examines the role of different machine learning (ML) algorithms to determine which socio-demographic factors and hand-forearm anthropometric dimensions can be used to accurately predict hand function. Methods. The cross-sectional study was conducted with 7119 healthy Iranian participants (3525 males and 3594 females) aged 10-89 years. Seventeen hand-forearm anthropometric dimensions were measured by JEGS digital caliper and a measuring tape. Tip-to-tip, key and three-jaw chuck pinches were measured using a calibrated pinch gauge. Subsequently, 21 features pertinent to socio-demographic factors and hand-forearm anthropometric dimensions were used for classification. Furthermore, 12 well-known classifiers were implemented and evaluated to predict pinches. Results. Among the 21 features considered in this study, hand length, stature, age, thumb length and index finger length were found to be the most relevant and effective components for each of the three pinch predictions. The k-nearest neighbor, adaptive boosting (AdaBoost) and random forest classifiers achieved the highest classification accuracy of 96.75, 86.49 and 84.66% to predict three pinches, respectively. Conclusions. Predicting pinch strength and determining the predictive hand-forearm anthropometric and socio-demographic characteristics using ML may pave the way to designing an enhanced tool handle and reduce common musculoskeletal disorders of the hand.

Effects of weights applied to the apex of a bag-valve-mask and pinch strength on tidal volume: a prospective simulation study.

A bag-valve-mask (BVM) is a first aid tool that can easily and quickly provide positive-pressure ventilation in patients with breathing difficulties. The most important aspect of BVM bagging is how closely the mask adheres to the patient's face when the E-C technique is used. In particular, the greater the adhesion force at the apex of the mask, the greater the tidal volume. The purpose of this study was to investigate the effect of various weights applied to the mask's apex and the pinch strength needed to perform the E-C technique, on tidal volume. In this prospective simulation study, quasi-experimental and equivalent time-series designs were used. A total of 72 undergraduate paramedic student from three universities were recruited using convenience sampling. The tidal volumes according to the weights (0 g, 100 g, 200 g, 300 g) applied to the apical area of the mask, handgrip strength, and pinch strength (tip pinch strength, key pinch strength, and tripod pinch strength) were measured. A linear mixed model analysis was performed. Linear mixed model analyses showed that tidal volume was significantly higher at 200 g (B = 43.38, p = 0.022) and 300 g (B = 38.74, p = 0.017) than at 0 g. Tripod pinch strength (B = 12.88, p = 0.007) had a significant effect on mask adhesion for effective BVM ventilation. Adding weight to the apical area of the mask can help maintain the E-C technique and enable effective ventilation. Future studies are required to develop specific strategies to improve the ventilation skills, which can be an important first-aid activity.

Are there any benefits for post-operative splinting after carpal tunnel release? A systematic review and meta-analysis.

BACKGROUND: There is a controversy on the effectiveness of post-operating splinting in patients with carpal tunnel release (CTR) surgery. This study aimed to systematically evaluate various outcomes regarding the effectiveness of post-operating splinting in CTR surgery. METHODS: Multiple databases, including PubMed, EMBASE, CINAHL, Web of Science, and Cochrane, were searched for terms related to carpal tunnel syndrome. A total of eight studies involving 596 patients were included in this meta-analysis. The quality of studies was evaluated, and their risk of bias was calculated using the methodological index for non-randomized studies (MINORS) and Cochrane's collaboration tool for assessing the risk of bias in randomized controlled trials. Data including the visual analogue scale (VAS), pinch strength, grip strength, two-point discrimination, symptom severity score (SSS), and functional status scale (FSS) were extracted. RESULTS: Our analysis showed no significant differences between the splinted and non-splinted groups based on the VAS, SSS, FSS, grip strength, pinch strength, and two-point discrimination. The calculated values of the standardized mean difference (SMD) or the weighted mean difference (WMD) and a 95% confidence interval (CI) for different variables were as follows: VAS [SMD = 0.004, 95% CI (-0.214, 0.222)], pinch strength [WMD = 1.061, 95% CI (-0.559, 2.681)], grip strength [SMD = 0.178, 95% CI (-0.014, 0.369)], SSS [WMD = 0.026, 95% CI (- 0.191, 0.242)], FSS [SMD = 0.089, 95% CI (-0.092, 0.269)], and the two-point discrimination [SMD = 0.557, 95% CI (-0.140, 1.253)]. CONCLUSIONS: Our findings revealed no statistically significant differences between the splinted and non-splinted groups in terms of the VAS, SSS, FSS, grip strength, pinch strength, and two-point discrimination. These results indicate that there is no substantial evidence supporting a significant advantage of post-operative splinting after CTR.

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.

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.

Evaluation of the Association Between Carrying Angle, Hand Grip Strength, Lateral Pinch Strength, and Hand Functional Index in Nursing Students / Evaluación de la Asociación entre el Ángulo de Carga, la Fuerza de Agarre de la Mano, la Fuerza de Pellizco Lateral y el Índice Funcional de la Mano en Estudiantes de Enfermería

SUMMARY: Health professionals especially nurses have ongoing contact with patients and they may have a high incidence of musculoskeletal problems. For this reason, grip strength and carrying angle are important parameters for all health professionals to succeed in their job and avoid injuries. It was aimed to determine the effects of the hand grip, and pinch strength, carrying angle of dominant, and non-dominant hands as well as the association of the hand functional index with morphometric measurements in 193 nursing students. The means of the carrying angle of dominant and non-dominant sides were 169.11±4.21° and 168.16±4.30°, respectively. The means of the dominant and, non-dominant sides of hand grip strength were 45.99±11.24 kg and 45.89±11.34 kg, respectively. The lateral pinch strength means were measured as 19.55±3.75 kg and 19.31±3.45 kg, respectively. This paper's findings may be important for some experts such as anatomists, clinicians, surgeons, forensic scientists, anthropologists, and nurses- healthcare professionals keep in touch with patients. Also, we believe that appropriate and effective knowledge of carrying angle, hand grip and lateral pinch strength has created an opportunity to research in terms of reducing work-related risk factors.

Los profesionales de la salud, especialmente las enfermeras, se mantienen en contacto con los pacientes y pueden tener una alta incidencia de problemas musculo-esqueléticos. En consecuencia, la fuerza de agarre y el ángulo de carga son parámetros importantes para que todos los profesionales de la salud tengan éxito en su trabajo y eviten las lesiones. El objetivo de este estudio fue determinar los efectos de la fuerza de prensión y pinzamiento de la mano, el ángulo de carga de las manos dominantes y no dominantes, así como la asociación del índice funcional de la mano con medidas morfométricas en 193 estudiantes de enfermería. Las medias del ángulo de carga de los lados dominante y no dominante fueron 169,11±4,21° y 168,16±4,30°, respectivamente. Las medias de los lados dominante y no dominante de la fuerza de prensión manual fueron 45,99 ± 11,24 kg y 45,89 ± 11,34 kg, respectivamente. La media de la fuerza de pellizco lateral se midió como 19,55 ± 3,75 kg y 19,31 ± 3,45 kg, respectivamente. Los hallazgos de este artículo pueden ser importantes para algunos expertos, como anatomistas, médicos clínicos, cirujanos, científicos forenses, antropólogos y enfermeras y profesionales de la salud que se mantienen en contacto con los pacientes. Además, creemos que el conocimiento apropiado y efectivo del ángulo de carga, el agarre de la mano y la fuerza de pellizco lateral ha creado una oportunidad para investigar en términos de reducción de los factores de riesgo relacionados con el trabajo.

Metacarpophalangeal joint angle of the thumb during maximal pinch strength: a study of healthy volunteers.

Mean metacarpophalangeal joint angles of the thumb during maximal pinch were 9° greater in men than in women. More flexion was not associated with more force during key pinch, but a moderate association was found for palmar pinch, especially in men.

Pinch strength analyses in lacertus syndrome.

PURPOSE: Lacertus syndrome is defined as proximal median nerve entrapment at the lacertus fibrosus. We aimed to analyze change in pinch strengths in patients who underwent median nerve release at the lacertus fibrosus under WALANT (wide-awake local anesthesia, no tourniquet). METHODS: Pinch strength was measured with a pinch gauge. Subjective DASH score and pain, numbness in the operated extremity and satisfaction on visual analog scales were analyzed before and 6 weeks after surgery. RESULTS: There were 32 patients. Median nerve release under the lacertus fibrosus elicited statistically significant increases in tip-to-tip, lateral and tripod pinch strength at postoperative week 6. Improvements in DASH score, pain and paresthesia were also statistically significant. CONCLUSIONS: For lacertus syndrome treatment, mini-incision release of the lacertus fibrosus under WALANT was satisfactory and increased pinch strength significatively. LEVEL OF EVIDENCE: Therapeutic, Level IV - Case series.

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.

Relationship between manual dexterity and left-right asymmetry of anatomical and functional properties of corticofugal tracts revealed by T2-weighted brain images.

The corticofugal tracts (CFT) are key agents of upper limb motor function. Although the tracts form high-intensity regions relative to surrounding tissue in T2-weighted magnetic resonance images (T2WI), the precise relations of signal intensities of the left and right CFT regions to hand function are unknown. Here, we tested the hypothesis that the different signal intensities between the left and right CFT signify clinically important differences of hand motor function. Eleven right-handed and eleven left-handed healthy volunteers participated in the study. Based on horizontal T2WI estimates, we confirmed the relationship between the signal intensity ratios of the peak values of each CFT in the posterior limbs of the internal capsules (right CFT vs. left CFT). The ratios included the asymmetry indices of the hand motor functions, including grip and pinch strength, as well as the target test (TT) that expressed the speed and accuracy of hitting a target ([right-hand score - left-hand score]/[right-hand score + left-hand score]), using simple linear regression. The signal intensity ratios of each CFT structure maintained significant linear relations with the asymmetry index of the speed (R2 = 0.493, P = 0.0003) and accuracy (R2 = 0.348, P = 0.004) of the TT. We found no significant association between left and right CFT structures for grip or pinch strengths. The findings are consistent with the hypothesis that the different signal intensities of the left and right CFT images captured by T2WI serve as biological markers that reflect the dominance of manual dexterity.

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.

Force-amplifying implant to improve key pinch strength in tendon transfer surgery: Cadaver model proof-of-concept.

The brachioradialis (BR) to flexor pollicis longus (FPL) tendon transfer surgery is a common procedure used to restore key pinch grip for incomplete spinal cord injury patients. However, the procedure only restores 22% of the physiological grip strength, which is important for successfully grasping objects and minimizing fatigue. The purpose of this study was to evaluate the efficacy of using a novel force-amplifying pulley implant to modify the standard BR to FPL tendon transfer surgery to improve key pinch grip strength in a human cadaver forearm model. A total of eight cadaveric specimens were mounted onto a custom testbed where a torque-controlled motor actuated the BR tendon to produce key pinch grip. In each cadaver, two experimental groups were examined: a standard and an implant-modified BR to FPL tendon transfer surgery. A force sensor mounted to the thumb recorded isometric key pinch grip forces over a range of input BR forces (2 N-25 N) applied in a ramp-and-hold protocol. Across the range of input BR forces, the average improvement in key pinch grip strength in the implant-modified surgery compared to the standard surgery was 58 ± 7.1% (ranging from 41% to 64% improvement). Throughout the experiments, we observed that the implant did not hinder the movement of the BR or FPL tendons. These results suggest that a BR to FPL tendon transfer surgery utilizing a force-amplifying pulley implant to augment force transmission can provide additional functional strength restoration over the standard procedure that directly sutures two tendons together.

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.

Test-Retest Reliability of a Static and Dynamic Motor Fatigability Protocol Using Grip and Pinch Strength in Children With Cerebral Palsy.

OBJECTIVE: The purpose of this study was to investigate the test-retest reliability, measurement error, and interpretability of new motor fatigability outcomes of grip and pinch strength for children with unilateral cerebral palsy (UCP). METHODS: Motor fatigability during grip and pinch strength was measured twice (within 48 hours) in both hands of 50 children (mean age = 11 years 2 months; 14, 31, and 5 children with Manual Ability Classification System levels I, II, and III, respectively) using a 30-second static and dynamic maximum exertion protocol. For static motor fatigability, the Static Fatigue Index (SFI) and mean force (Fmean) in the first (Fmean1) and last (Fmean3) 10 seconds were calculated. For dynamic motor fatigability, Fmean1, Fmean3, and the number of peaks in the first and last 10 seconds were calculated. RESULTS: For static motor fatigability, the intraclass correlation coefficients (ICCs) were moderate to high for Fmean1 and Fmean3 (0.56-0.88), and the SFI showed low to moderate reliability (ICC = 0.32-0.72). For dynamic motor fatigability, the ICCs were moderate to high for all outcomes (0.54-0.91). The standard error of measurement agreement and the smallest detectable difference agreement were large in all outcomes, except for the SFI in static motor fatigability. Details per age group are provided. In general, younger children (6-11 years old) showed lower reliability than older children (12-18 years old). CONCLUSION: Most outcome measures for static and dynamic motor fatigability of grip and pinch strength show moderate to high reliability in children with UCP, indicating that these tests can be used reliably to investigate the presence of motor fatigability in UCP, especially in older children. Standard error of measurement agreement and smallest detectable difference agreement indicated that these outcome measures should be interpreted with caution when evaluating change. IMPACT: Most of the proposed outcome measures for static and dynamic motor fatigability of grip and pinch are reliable in children with UCP and can be used for discriminative purposes.

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.

Hand functionality in dentists: the effect of anthropometric dimensions and specialty.

Objectives. This study aimed to investigate the relationship between dentists' hand functionality (handgrip, tip-to-tip pinch, key pinch and palmar pinch strengths) and dental specialty (maxillofacial surgery, endodontics, pediatric dentistry), socio-demographic factors and hand-forearm anthropometric dimensions. Methods. A cross-sectional study was designed in which 720 certified dentists (330 males and 390 females) voluntarily participated in the study. A tape measure (±0.1 cm) and a digital caliper (±0.1 mm) were used to measure anthropometric dimensions. A Jamar dynamometer and pinch gauge were used to measure hand strength variables. Results. Hand strengths decreased with age and clinical experience, and were always greater in male than female dentists. Maxillofacial surgeons aged 35-39 years attained the highest values of handgrip and key pinch strengths, while endodontists aged 30-34 years attained the peak values of tip-to-tip pinch strength. Among the measured hand dimensions, forearm circumference was significantly greater in maxillofacial surgeons compared with endodontists and pediatric dentists. Conclusion. Hand functionality is specialty-related among dentists because distinct dental specialties expose practitioners to different task demands. Like any other manual workers, dentists need more ergonomic and usable hand tools tailored not only to the intended application but also to the anthropometry of users.

A quantitative measurement of trapeziometacarpal joint pressure using a cadaveric model of lateral pinch.

Trapeziectomy is performed for trapeziometacarpal (TMC) arthritis but decreased lateral pinch strength is a major source of discomfort after the surgery. The magnitude of the decrease is unclear, however, and how the pressure changes in the TMC joint is unknown. To investigate this relationship, we designed a cadaveric study to measure TMC joint pressure using a lateral pinch model, and quantitatively evaluated the effect of trapeziectomy on the pressure measurements. For 10 cadaveric forearms, physiologic forces were applied across the thumb TMC joint by loading five tendons, thereby simulating lateral pinch. Using pressure sensors, we measured the lateral pinch pressure and TMC joint pressure, which averaged 10.1 (range, 4.2-16.2) kg/cm2 and 2.0 (range, 0.8-4.4) kg/cm2 , respectively. A significant correlation between the measurements was found, with an average ratio of 19% (range, 10%-27%). After trapeziectomy and interposition of the tendon ball using flexor carpi radialis, the pressure measurements were repeated under the same conditions. Significant changes were found, which averaged 5.1 (range, 1.7-10.7) kg/cm2 for lateral pinch pressure and 15.0 (range, 5.6-25.6) kg/cm2 for TMC joint pressure. In conclusion, TMC joint pressure could be measured as the ratio relative to lateral pinch pressure using a cadaveric model. After trapeziectomy, the lateral pinch strength decreased, whereas the TMC joint pressure increased.