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.

Normative Data of Grip Strength and Pinch Strength in the Indian Population.

Background There is no normative study of transregional grip strength data available from India. Hence, a multicenter study is designed to obtain reference value. Materials and Methods This is a prospective observational study conducted as a part of the Indian normative data project of the Indian Society for Surgery of the Hand. The study included three participating centers: one from the northern part and two from the southern part. Certified calibrated Jamar dynamometer and Jamar pinch gauge were used to measure the grip strength, key pinch strength, tip pinch strength, and tripod pinch strength as per the guidelines of the American Society of Hand Therapists. Results A total of 1,019 volunteers in the age group of 18 to 60 years were studied. The mean grip strength in males and females was 38.18 and 24.06 kg, respectively. The mean key pinch strength was 8.52 kg in males and 5.97 kg in females. The mean tip pinch strength was 4.86 kg in males and 3.59 kg in females. The mean tripod pinch strength was 5.41 kg in males and 4.16 kg in females. Conclusions All four strengths were lower in value when compared with American and other populations. The men had more strength than women. There was no relation to hand dominance. There was a correlation for age and height but no correlation with body mass index (BMI).

Population Norms for Hand Grip and Precision Grip Strengths in Polish Children and Adolescents Aged 3-19.

Background: Normative data on hand and precision grip strengths are essential for evaluating the level of development, the efficacy of rehabilitation, and treatment results. The need for established norms of grip strength in Polish children is one of the problems that Polish physiotherapists and physicians face when treating upper limbs. The aim was to establish normative values of hand and precision grips strengths in Polish children and adolescents aged 3-19. Methods: In the years 2012-2023, a sample of 358 children and adolescents with no history of upper limb injuries or congenital upper extremity defects were randomly chosen from kindergartens, primary schools, middle schools, and high schools. They were living in urban agglomerations and in smaller towns or villages. Hand and precision grips like the pincer, three-point, side, and opposition grip strength were assessed using a hand dynamometer and pinchmeter in standard positions. Results: The strength in all types of examined hand grips increases with chronological age in both genders. The grip strength was higher in the boys' group than in the girls' and it was higher in the right hand than in the left, but the difference was no more greater than 10%. Detailed data with standard deviation were presented in the form of a table, divided by age and sex. Conclusions: Norms for grip strength were provided for Polish children and adolescents aged 3-19, allowing therapists and physicians to compare Polish patients with that of normally developed, healthy children of the same age and sex.

Reliability, validity, and responsiveness of pinch strength assessment: a systematic review.

PURPOSE: To summarize and critically appraise the quality of studies investigating psychometric properties of pinch strength assessment. METHODS: Medical literature up to February 2024 was searched for studies reporting on at least one measurement property of pinch strength assessment. The quality of the evidence and the risk of bias were rated using COSMIN 2018 guidelines. RESULTS: Thirty-three studies (1962 participants) were included. The majority (16/19) of reliability studies were of adequate to very good quality. Seven of 12 studies of validity were rated as adequate or very good. The quality of the eight responsiveness studies was adequate. Reliability was good to excellent (ICC > 0.75) for neurological conditions, and excellent (ICC > 0.90) for musculoskeletal disorders and healthy participants. Pinch strength showed strong to very strong correlations with grip strength (r = 0.72-0.92), moderate to strong correlations with assessments of dexterity (r = 0.78-0.80), and weak to moderate correlation with patient-reported outcome measures (r = 0.03-0.50). Varied results were found for pinch strength responsiveness in a small number of studies. CONCLUSIONS: Pinch strength assessment is reliable. Validity and responsiveness are less reported, but there is a strong correlation between pinch and grip strength, and a moderate correlation with dexterity.

This review demonstrated that the reliability of pinch strength assessment is good to excellent.Clinicians can measure pinch strength and expect accurate results over repeated measurements and between raters.There is a strong correlation between pinch and grip strength, and a moderate correlation between pinch strength and hand dexterity.The low correlation between pinch strength and patient-reported outcome measures highlights the need to measure these outcomes independently of each other.

Using a Sensor-Embedded Baseball to Identify Finger Characteristics Related to Spin Rate and Pitching Velocity in Pitchers.

BACKGROUND: Previous investigations have shown a positive relationship between baseball pitching velocity and the kinetic chain involved in pitching motion. However, no study has examined the influence of finger characteristics on pitching velocity and rate of spin via a sensor-embedded baseball. METHODS: Twenty-one pitchers volunteered and were recruited for this study. An experimental baseball embedded with a force sensor and an inertial measurement unit was designed for pitching performance measurement. Finger length and strength were measured as dependent variables. Spin rate and velocity were independent variables. Pearson product-moment correlations (r) and intraclass correlation coefficients (ICCs) determined the relationship between finger characteristics and pitching performance. RESULTS: Finger length discrepancy, two-point pinch strength, index finger RFD (rate of force development), middle finger impulse, and force discrepancy had significant correlations with spin rate (r = 0.500~0.576, p ≤ 0.05). Finger length discrepancy, two-point pinch, three-point pinch strength, index and middle finger RFD, middle finger impulse, and force combination had significant correlations with fastball pitching velocity (r = 0.491~0.584, p ≤ 0.05). CONCLUSIONS: Finger length discrepancy, finger pinch strength, and pitching finger force including maximal force and RFD may be factors that impact fastball spin rate and fastball pitching velocity.

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.

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.

Effect of physical therapy interventions in individuals with primary thumb carpometacarpal osteoarthritis: a systematic review and meta-analysis.

PURPOSE: This systematic review and meta-analysis aimed to investigate the effect of physiotherapeutic interventions in individuals with thumb primary CMC OA on the outcomes of pain, hand function, grip or pinch strength. METHODS: RCTs that used some type of physiotherapeutic intervention compared to a passive or active control group were included. The quality of the evidence was assessed using the GRADE approach and, for the calculation of the meta-analysis, the standardized difference of means (SMD) was used. RESULTS: Nineteen studies (n = 1477) were included and eight studies (n = 568) underwent meta-analysis. Orthosis intervention was superior to passive control group for pain improvement (SMD = -1.02, p = 0.03, very low evidence), grip strength (SMD = 0.45, p = 0.02, very low evidence) and pinch strength (SMD = 1.78, p = 0.01, very low evidence), but there was no improvement in hand function (p = 0.54). The use of a neoprene orthosis was similar to the use of a thermoplastic orthosis in improving pain (p = 0.38), hand function (p = 0.50), grip strength (p = 0.42) and pinch strength (p = 0.14). The use of short thermoplastic orthosis was also similar to long thermoplastic orthosis in improving pain (p = 0.88) and hand function (p = 0.58). CONCLUSION: The use of orthoses is superior to no intervention in all outcomes, exception hand function.IMPLICATIONS FOR REHABILITATIONThe use of orthosis is recommended for the treatment of patients with rhizoarthrosisUse of orthosis is better than no intervention in improving pain, grip and pinch strength.The type of orthosis (neoprene or thermoplastic, short or long thermoplastic) does not affect the clinical improvement of the individual to the outcomes of pain, hand physical function, grip and pinch strength.

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.

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.

Effect Of Texting And Handwriting On Hand-Grip And Key-Pinch Strength Among Female-Collegiate Students: Randomized Controlled Trial.

OBJECTIVE: To evaluate immediate and long-term effect of texting or handwriting on hand-grip and key-pinch strength among healthy female students. Methods: The single-blind, randomised controlled trial was conducted between February and April 2021 after approval from the ethics review committee of the College of Medical Rehabilitation Sciences, Taibah University, Saudi Arabia, and comprised female Physio Therapy students aged 19-23 years who were right-hand dominant and had normal body mass index. The subjects used smartphones and electronic gadgets for >2hrs daily, writing more than 10min/day. They were randomised using sealed envelopes into five groups. Group A practised 10min texting, group B 15min texting, group C 10min writing, group D 15min writing, and group E used the phones only for talking or watching, with no texting or writing, and was taken as the control group. Hand-grip strength and key- pinch strength were assessed one minute before starting, and within one minute after having finished the assigned hand activity. All measurements were recorded in the sitting position using a single hand-grip dynamometer. Data was analysed using SPSS 23. RESULTS: Of the 65 individuals assessed, 60(92.3%) were initially enrolled, but the study was finished by 50(83.3%) subjects with a mean age of 20.88±0.98 years and mean body mass index 20.8±2.30kg/m2. There were 12(24%) subjects in group A, 7(14%) in group B, 12(24%) in group C, 10(20%) in group D and 9(18%) in group E. The association of the time-based groups with hand-grip and key-pinch strength was not significant (p>0.05). CONCLUSIONS: Texting and handwriting did not have any significant immediate effect on hand- grip or key-pinch strength. Clinical Trial Number: (NCT04810416).

Challenges in evaluating forearm muscle activity based on the compound muscle action potential of the flexors of the whole forearm.

Objective: Muscle strength, which correlates with the compound muscle action potential (CMAP), can also be estimated by measuring the CMAP. Therefore, we evaluated the CMAP of the flexor muscles of the whole forearm to identify their muscle strength. Methods: Fourteen healthy volunteers were enrolled. The elbow was determined to be the stimulation point, and the recording site for the flexor muscles of the whole forearm was set at approximately 8 cm distal to the elbow. We prospectively evaluated the baseline-to-peak amplitude of the CMAP of the whole forearm flexor muscles (WFFM), including that obtained from the median nerve stimulation (WFFMm), ulnar nerve stimulation (WFFMu), and their sum (WFFMsum). Additionally, we analyzed the relationships between WFFMm and WFFMu amplitudes with other quantitative parameters, including grip strength and routine CMAP amplitudes. Results: The CMAP's test-retest analysis revealed high reliability. Grip power was significantly correlated with WFFMm and WFFMsum and mildly correlated with WFFMu. Tip-pinch strength with WFFMm and flexor pollicis longus (FPL) measurements correlated significantly. Lateral-pinch strength was significantly correlated with the first dorsal interosseous muscle (FDI) measurements but not with WFFM. The abductor digiti minimi (ADM) and abductor pollicis brevis (APB) were not correlated with grip power or pinch strength. Conclusions: By electrophysiology examination, this study demonstrated that WFFMm is involved in grip power and other pinch strengths. This method may serve as a novel tool for measurement of distal muscle strengths. Significance: This is the first study to attempt to evaluate the muscle strength of forearm flexor muscles by measuring the CMAP.

Normative Values for Pinch Strength-Relationship With Joint Hypermobility as Measured With the Beighton Criteria.

Purpose: This study aimed to determine normative ranges of static pinch strength as measured with a spring gauge in adults of working age and investigate whether pinch strength is associated with hand hypermobility. A secondary aim was to explore whether the Beighton criteria for hypermobility are associated with hypermobility in joints of the hand during forceful pinching. Methods: A convenience sample of healthy men and women aged 18-65 years were recruited for measurement of lateral pinch, 2-point pinch, 3-point pinch, and joint hypermobility according to the Beighton criteria. Regression analysis was used to determine the effect of age, sex, and hypermobility on pinch strength. Results: Two hundred and fifty men and 270 women participated in this study. Men were stronger than women at all ages. Lateral and 3-point pinch were greatest for all participants and 2-point pinch was the least strong. There were no statistically significant differences between age groups, but a trend for the lowest pinch strength to occur before the mid-thirties was seen in both sexes. Thirty-eight percent of women and 19% of men were hypermobile; however, these participants statistically insignificant differ in pinch strength compared with other participants. The Beighton criteria corresponded strongly with hypermobility in other joints of the hand as observed and photographed during pinch. Hand dominance did not show clear relationships with pinch strength. Conclusions: Normative lateral, 2-point, and 3-point pinch strength data for adults of working age are presented with men having greatest pinch strength at all ages. The Beighton criteria for hypermobility are associated with hypermobility in other joints of the hand. Clinical Relevance: Benign joint hypermobility is not related to pinch strength. Men have greater pinch strength at all ages than women.

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.

Investigation of grip strength, pain threshold, pain tolerance and function in smartphone users.

PURPOSE/AIM OF THE STUDY: Few studies have demonstrated the effects of smartphone use on grip strength and upper extremity function. The present study was purposed to compare smartphone users' grip/lateral pinch strength, pain threshold/tolerance and upper limb function. MATERIALS AND METHODS: A prospective cross-sectional study was conducted with 241 individuals. Participants were divided into three groups with the cut-off values of the Smartphone Addiction Scale (SAS). The Edinburgh Handedness Inventory (EHI) was used to determine the dominant side. Thumb pain threshold and tolerance were evaluated with the algometer. A hand dynamometer measured the grip and lateral pinch strength. Upper extremity functions were evaluated with the Shortened Disabilities of the Arm, Shoulder and Hand Questionnaire (Quick-DASH). RESULTS: Handgrip strength of the dominant/non-dominant extremities and Quick-DASH scores were higher in low-level smartphone users (p < 0.05). There was no significant difference between the groups on lateral pinch strength and pain threshold/tolerance (p > 0.05). Smartphone usage significantly affected dominant and non-dominant hand grip strength (Standardized ß1 = -0.15, ß2 = -0.15, p < 0.05). In addition, the smartphone use level negatively affected dominant lateral pinch strength (Standardized ß = -0.12, p = 0.05). On the other hand, smartphone use positively affected upper extremity function (Standardized ß = 0.17, p < 0.05). CONCLUSIONS: As smartphone addiction increases, standard handgrip strength and functionality decrease. Pain threshold/tolerance is not affected by smartphone use. Future studies should focus on fine motor skills to present a more comprehensive upper limb function evaluation.

The effect of task-oriented circuit training-based telerehabilitation on upper extremity motor functions in patients with Parkinson's disease: A randomized controlled trial.

INTRODUCTION: Upper extremity functions are impaired in patients with Parkinson's disease (PwPD), which leads to difficulties in activities of daily living (ADL), such as reaching or handwriting. The aim of this study was to investigate the effectiveness of task-oriented circuit training-based telerehabilitation (TOCT-TR) on the upper extremity motor function in PwPD. METHODS: In this randomized controlled trial (RCT) 30 PwPD (aged 45-70 years, Hoehn & Yahr stage I-III) were recruited and randomly allocated into two groups. The TOCT-TR group received home training through video sessions three days/week for six weeks. Additionally, both the TOCT-TR group and the control group (CG) underwent home exercises aimed at improving balance, gait, and mobility three days/week for six weeks. The primary outcome measure was upper extremity motor functions measured with the Nine Hole Peg test (9-HPT), the Jebsen Hand Function Test (JHFT), grip strengths, pinch strengths, and the Unified Parkinson's Disease Rating Scale-III (UPDRS-III). Secondary outcome measures included the UPDRS-II and the quality of life (QoL, PDQ-8). RESULTS: This study showed significant group-by-time interactions on the 9-HPT (p < 0.001), the JHFT (p < 0.001), grip strengths (p < 0.001), pinch strengths (p ≤ 0.015), and the UPDRS-III (p = 0.007) in favor of the TOCT-TR. Additionally, the UPDRS-II (p < 0.001), and the PDQ-8 (p = 0.005) improved in both groups. CONCLUSION: This is the first RCT showing that the TOCT-TR improved upper extremity motor functions, ADL, and QoL in PwPD. The TOCT-TR may help improve the upper extremities of PwPD who have difficulties reaching rehabilitation clinics.

A human, allogeneic cortical bone screw for distal interphalangeal joint (DIP) arthrodesis: a retrospective cohort study with at least 10 months follow-up.

INTRODUCTION: The prime requisites of a good digital arthrodesis are a painless and stable union in a proper position. Arthrodesis of the distal interphalangeal joint of the fingers is not without potential complications including nonunion, malunion, and deep tissue infections. The Shark Screw® is a human, cortical bone allograft for osteosynthesis and an alternative to metal or bioabsorbable devices in orthopedics and trauma surgery. The primary hypothesis is that the fusion and complication rate, using the Shark Screw®, is at least similar to those reported in the literature, using metal or bioabsorbable screws. MATERIAL AND METHODS: This retrospective cohort study analyzes the fusion and complication rate and the patient satisfaction of distal interphalangeal joint arthrodesis of 27 fingers with the human allogeneic cortical bone screw. Complications, Disabilities of Arm, Shoulder, and Hand Questionnaire (Quick-DASH) score and Michigan Hand Outcomes Questionnaire (MHQ) score, grip and pinch strength and fusion angle were investigated. RESULTS: The mean follow-up was 23 months. At 6 weeks after surgery, fusion was obtained for all fingers. There was no surgical complication that required revision surgery. An average fusion angle of 13.6° ± 10.7° was measured. VAS pain score decreased significantly from 6.9 before surgery to 0.14 after surgery. The Quick-DASH score decreased from 10.7 to 7.8. The MHQ score improved in all sub-scores. CONCLUSION: The complication rates, using the Shark Screw® for DIP joint arthrodesis, are lower compared to the results reported in the literature for other surgical techniques. Complications related to the human allograft cortical bone screw itself were not observed. The bone screw is completely remodeled into the host bone and further hardware removal is not necessary. LEVEL OF EVIDENCE: IV.

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.

Investigation of hand functions in individuals with cannabis and its derivatives use disorder.

BACKGROUND: The present study was aimed to compare the grip/pinch strengths and manual dexterity of individuals with and without the use of cannabis and its derivatives. METHODS: A cross-sectional prospective study was conducted with 66 individuals, including 33 cases with the use of cannabis (and its derivatives) and 33 age- and sex-matched controls. Grip and pinch strengths were evaluated with a dynamometer. The Nine-Hole Peg Test (9HPT), Minnesota Manual Dexterity Test (MMDT), and Michigan Hand Outcomes Questionnaire (MHQ) were used to assess the hand function. RESULTS: The hand grip strength and dominant hand 2-point pinch (2PP) grip strength were less in individuals with substance use disorder (SUD) (p < 0.05). The 9HPT duration of the SUD patients was higher (p < 0.05). On the other hand, the MMDT insertion and rotation test results were different between the groups (p < 0.05). Grip strength was related with the MMDT insertion and rotation tests (r = -0.411 to -0.480). There was significant correlation between grip strength with dominant hand 9HPT (r = -0.370) and between dominant hand 3-point pinch (3PP) strength with MMDT insertion (r = -0.378). In addition, dominant hand 2PP strength was correlated with overall hand function of MHQ (r = 0.382). CONCLUSION: The individuals with cannabis use disorder showed reduced grip strength on both sides and decreased 2PP strength on the dominant side compared to healthy individuals. In addition, there is a decrease in the hand skills of individuals with cannabis use disorder. Decreased grip strength of individuals with cannabis use disorder affected their hand skills negatively.

Determinants of hand function in children and adolescent with Down Syndrome-A scoping review.

BACKGROUND: Down Syndrome (DS) is a genetic condition. Physical characteristics like short stature, hypotonia, small, and thick hands result in decreased grip and pinch strength and quality of fine motor tasks. PURPOSE: The purpose of this review is to summarize the evidence of upper extremity physical characteristics and its influence on hand function in DS population. STUDY DESIGN: A scoping review. METHODOLOGY: A comprehensive electronic literature search was conducted through PubMed, CINAHL, Cochrane Library. The search was limited to articles written in English and published between 2010 to 2021. Additionally, books were referred for a better understanding of the hand function in DS. The Preferred Reporting Items for Systematic Review and Meta-Analysis extension for scoping reviews (PRISMA-ScR) was adopted to develop the protocol. RESULTS: Following a detailed review of 28 articles meeting the inclusion criteria, fetuses with a diagnosis of DS are reported to have shortening of humerus on sonographic markers wherein 9% of fetuses had below 5th percentile shortening. Additionally, literature reports that during reaching there was increased trunk rotation (effect size = 0.88). DS population had 60% less grip strength, 33% less palmar pinch strength ,20% less key pinch strength and poor manual dexterity (CI = 4.5-5.5). CONCLUSION: Findings of this review concludes that physical characteristics of the upper extremity have an influence on hand function performance in children and adolescents with DS.However, only arm length and hand span have been quantified and correlated with grip strength. Further work must focus on correlation of upper extremity anthropometry and overall hand function in children and adolscents with DS.