Martin Vigorimeter Research Articles

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.

Reliability and Validity of the Martin Vigorimeter for Grip Strength Measurement in Korean Adults.

Grip strength is important for fine motor skills, and one of the measurement tools for grip strength is the Martin Vigorimeter (MV) dynamometer. Studies on establishing the reliability and validity of the MV in Koreans are limited. We aimed to establish the reliability and validity of the MV for grip strength measurement in healthy Korean adults by comparing it with the Jamar dynamometer, the standard tool used by the American Society of Hand Therapists. In total, 99 healthy participants (50 men and 49 women) were enrolled. Grip strength was measured using the Jamar dynamometer and MV. Reliability and validity were assessed using the intraclass correlation coefficient (ICC) and minimal detectable change (MDC). The correlation between the measurements of the instruments was analyzed using Pearson's correlation. The effect of hand anthropometry was evaluated, and the conversion equation between the instruments was calculated. MV showed excellent reliability (ICC > 0.90, p < 0.001) and validity with a high correlation (0.7 ≤ r < 0.9) with the Jamar dynamometer. The MDC was acceptable for detecting minimal clinically important differences (< 19.5%) in both instruments (Jamar: 3.4%-6.7%, MV: 3.8% to 6.3%). The grip strength measured using the MV was independent of hand anthropometry, unlike that using the Jamar dynamometer. This study provides insights into the relationship between the Jamar and MV instruments for measuring grip strength in Koreans. The MV is a viable alternative to the Jamar dynamometer in Koreans, offering not only reproducible and reliable measurements of grip strength but also the advantage of being unaffected by variations in hand anthropometry.

Grip strength cut-points from the Swiss DO-HEALTH population

BackgroundWhile grip strength (GS) is commonly assessed using a Dynamometer, the Martin Vigorimeter was proposed as an alternative method especially in older adults. However, its reference values for Swiss older adults are missing. We therefore aimed to derive sex- and age-specific GS cut-points for the dominant and non-dominant hand (DH; NDH) using the Martin Vigorimeter. Additionally, we aimed to identify clinically relevant weakness and assess convergent validity with key markers of physical function and sarcopenia in generally healthy Swiss older adults.MethodsThis cross-sectional analysis includes baseline data from Swiss participants enrolled in DO-HEALTH, a 3-year randomized controlled trial in community-dwelling adults age 70 + . For both DH and NDH, 4 different definitions of weakness to derive GS cut-points by sex and age category (≤ 75 vs. > 75 years) were used: i) GS below the median of the 1st quintile, ii) GS below the upper limit of the 1st quintile, iii) GS below 2-standard deviation (SD) of the sex- and age-specific mean in DO-HEALTH Swiss healthy agers (i.e. individuals without major chronic diseases, disabilities, cognitive impairment or mental health issues) and iv) GS below 2.5-SD of the sex- and age-specific mean in DO-HEALTH Swiss healthy agers. To assess the proposed cut-points’ convergent validity, we assessed their association with gait speed, time to complete the 5 Times Sit-To-Stand (5TSTS) test, and present sarcopenia.ResultsIn total, 976 participants had available GS at the DH (mean age 75.2, 62% women). According to the 4 weakness definitions, GS cut-points at the DH ranged from 29–42 and 25–39 kPa in younger and older women respectively, and from 51–69 and 31–50 kPa in younger and older men respectively. Overall, weakness prevalence ranged from 2.0% to 19.3%. Definitions of weakness using the median and the upper limit of the 1st GS quintile were most consistently associated with markers of physical performance. Weak participants were more likely to have lower gait speed, longer time to complete the 5TSTS, and sarcopenia, compared to participants without weakness.ConclusionsIn generally healthy Swiss older adults, weakness defined by the median or the upper limit of the 1st GS quintile may serve as reference to identify clinically relevant weakness. Additional research is needed in less healthy populations in order to derive representative population-based cut-points.Trial registrationClinicalTrials.gov Identifier: NCT01745263.

Comparison between Two Different Handgrip Systems and Protocols on Force Reduction in Handgrip Assessment

Introduction: Fatigue resistance (FR) can be assessed as the time during which grip strength (GS) drops to 50% of its maximum during a sustained maximal voluntary contraction. For the first time, we compared force-time characteristics during FR test between two different handgrip systems and investigated age- and clinical-related differences in order to verify if a briefer test protocol (i.e., until 75%) could be sufficiently informative. Methods: A cohort of young healthy controls (Y, <30 y, 24 ± 3 y, 54% women), middle-aged (MA, 30–65 y, 47 ± 11 y, 54% women), and older (OLD, >65 y, 77 ± 7 y, 50% women) community-dwelling persons, and hospitalized geriatric patients (HOSP, 84 ± 5 y, 50% women) performed the FR test. For this purpose, an adapted vigorimeter (original rubber bulb of the Martin Vigorimeter connected to a Unik 5000 pressure gauge) here defined as “pneumatic handgrip system” (Pneu) and Dynamometer G200 system (original Jamar Dynamometer handle with an in-build strength gauge) here defined as “hydraulic handgrip system” (Hydr) were used. Force-time curves were analysed from 100% to 75% and from 75% to 50% of the initial maximal GS during the FR test. The area under the curve (GW) was calculated by integrating the actual GS at each time interval (i.e., 1/5,000 s) and corrected for body weight (GW/_{body weight}). Results: For both systems, we found fair associations between FR_100–50 and FR_100–75 (Pneu mean difference = 50.1 s [95% CI: 47.9–52.4], r² = 0.48; Hydr mean difference = 28.4 s [95% CI: 27.0–29.7], r² = 0.52, all p < 0.001) and also moderate associations between GW_{(100–50)/body weight} and GW_{(100–75)/body weight} (Pneu mean difference = 32.1 kPa*s/kg [95% CI: 30.6–33.6], r² = 0.72; Hydr mean difference = 8.1 kg*s/kg [95% CI: 7.7–8.6], r² = 0.68, all p < 0.001). Between MA and OLD, we found a significant age-related difference in the GW results in the first 25% strength decay for Pneu (10.2 ± 0.6 kPa*s/kg against 7.1 ± 1.2 kPa*s/kg, respectively). Conclusion: The brief test protocol is valid. Differences within the first 25% strength decay in GW between OLD and HOSP were identified when using Pneu but not when using Hydr. Therefore, a brief FR test protocol using a continuous registration of the strength decay seems to be sufficiently informative in a clinical setting to appraise muscle fatigability, however, only when using a Pneu system.

Hand grip strengthening exercises on fine motor skills in children with autism spectrum disorder

Background. Movement impairments in autism spectrum disorder (ASD) are manifested as both delays and deficits, with delays found in gross motor, fine motor and speech domains and deficits found in coordination, postural control and gait. Functional fine motor task is dependent on hand grip strength (HGS) which is found to be decreased. Therapeutic strategies focus primarily on sensory integration issues but HGS is not comprehensively addressed in improving fine motor skills (FMS). Objective. The aim of the study was to analyse the effect of hand grip strengthening exercises on improving FMS in children with ASD. Materials and Methods. This interventional study was carried out in 27 children with ASD who were recruited from Vidya sudha – Centre for children with special needs. After including in the study, level of FMS was assessed by Peabody Developmental Motor Scale (PDMS-2) and HGS was quantified with Martin Vigorimeter. Control group received conventional therapy and Intervention group received hand grip strengthening exercises along with routine therapy for duration of 6 weeks and HGS and level of FMS were reassessed with same outcome measures. Results. Paired t test showed statistically significant change of HGS in Intervention group and FMS of both the group with p &lt; 0.05. Unpaired t test showed statistically significant change of HGS and FMS with p &lt; 0.05 in Interventional group compared to control group. Conclusion. Hand grip strengthening exercises improves the HGS and has positive effect on FMS which can be included in the standard plan of care in rehabilitating children with ASD.

Validity and reliability of Eforto®, a system to (self-)monitor grip strength and muscle fatigability in older persons

IntroductionWe developed Eforto®, an innovative system for (self-)monitoring of grip strength (GS) and muscle fatigability (Fatigue Resistance (FR = time until GS decreased to 50% of maximum during sustained contraction) and grip work (GW = area under the strength-time curve)). The Eforto® system consists of a rubber bulb that is wirelessly connected to a smartphone-based application, and a telemonitoring platform. The aim was to evaluate the validity and reliability of Eforto® to measure muscle fatigability.MethodsCommunity-dwelling older persons (n = 61), geriatric inpatients (n = 26) and hip fracture patients (n = 25) were evaluated for GS and muscle fatigability. In community dwellers fatigability was tested twice in the clinic (once with Eforto®, once with Martin Vigorimeter (MV), standard analog handgrip system) and for six consecutive days as a self-assessment at home with Eforto®. In hospitalized participants, fatigability was tested twice using Eforto®, once by a researcher and once by a health professional.ResultsCriterion validity was supported by good to excellent correlations between Eforto® and MV for GS (r = 0.95) and muscle fatigability (FR r = 0.81 and GW r = 0.73), and no significant differences in measurements between both systems. Inter-rater and intra-rater reliability for GW were moderate to excellent (intra-class correlation: 0.59–0.94). The standard error of measurement for GW was small for geriatric inpatients and hip fracture patients (224.5 and 386.5 kPa*s) and higher for community-dwellers (661.5 kPa*s).Discussion/conclusionWe established the criterion validity and reliability of Eforto® in older community-dwelling persons and hospitalized patients, supporting the implementation of Eforto® for (self-)monitoring of muscle fatigability.

Hand grip strength and risk of incident venous thromboembolism: The Tromsø study

BackgroundHand grip strength (HGS), a common proxy of whole‐body muscular strength, is associated with a wide range of adverse health outcomes and mortality. However, there are limited data on the association between HGS and risk of venous thromboembolism (VTE). ObjectivesWe aimed to investigate the association between HGS and risk of incident VTE in a population‐based cohort. MethodsParticipants (n = 13,704) from the fourth to seventh surveys of the Tromsø study (Tromsø4–Tromsø7, enrollment: 1994–2016) were followed throughout 2020, and all incident VTEs were recorded. HGS of the nondominant hand was measured using a Martin Vigorimeter (Tromsø4–Tromsø6) and a Jamar Digital Dynamometer (Tromsø7). Hazard ratios (HRs) for VTE with 95% confidence intervals (CIs) according to weak HGS (less than 25th percentile) versus normal HGS (25th percentile or greater) were estimated using Cox regression models and adjusted for age, sex, body height, body mass index, physical activity, cardiovascular disease, and cancer. ResultsDuring a median of 6.5 years of follow‐up, 545 incident VTEs occurred. Participants with weak HGS had a 27% higher risk of VTE (HR, 1.27; 95% CI, 1.03–1.57) compared to those with normal HGS. Subgroup analyses revealed that the point estimates were higher for unprovoked VTE (HR, 1.35; 95% CI, 0.96–1.91) and deep vein thrombosis (DVT; HR, 1.52; 95% CI, 1.14–2.01). Similar results were found in analyses restricted to men, women, and elderly (aged greater than 75 years). ConclusionA weak HGS was associated with increased risk of VTE, and particularly unprovoked VTE and isolated DVT. Our findings suggest that weak muscle strength may be a risk factor for VTE.

Randomized trial of intravenous immunoglobulin maintenance treatment regimens in chronic inflammatory demyelinating polyradiculoneuropathy.

High peak serum immunoglobulin G (IgG) levels may not be needed for maintenance intravenous immunoglobulin (IVIg) treatment in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and such high levels may cause side effects. More frequent lower dosing may lead to more stable IgG levels and higher trough levels, which might improve efficacy. The aim of this trial is to investigate whether high frequent low dosage IVIg treatment is more effective than low frequent high dosage IVIg treatment. In this randomized placebo-controlled crossover trial, we included patients with CIDP proven to be IVIg-dependent and receiving an individually established stable dose and interval of IVIg maintenance treatment. In the control arm, patients received their individual IVIg dose and interval followed by a placebo infusion at half the interval. In the intervention arm, patients received half their individual dose at half the interval. After a wash-out phase patients crossed over. The primary outcome measure was handgrip strength (assessed using a Martin Vigorimeter). Secondary outcome indicators were health-related quality of life (36-item Short-Form Health Survey), disability (Inflammatory Rasch-built Overall Disability Scale), fatigue (Rasch-built Fatigue Severity Scale) and side effects. Twenty-five patients were included and were treated at baseline with individually adjusted dosages of IVIg ranging from 20 to 80g and intervals ranging from 14 to 35days. Three participants did not complete the trial; the main analysis was therefore based on the 22 patients completing both treatment periods. There was no significant difference in handgrip strength change from baseline between the two treatment regimens (coefficient -2.71, 95% CI -5.4, 0.01). Furthermore, there were no significant differences in any of the secondary outcomes or side effects. More frequent lower dosing does not further improve the efficacy of IVIg in stable IVIg-dependent CIDP and does not result in fewer side effects.

Home monitoring of maintenance intravenous immunoglobulin therapy in patients with chronic inflammatory neuropathy.

To evaluate the utility of different outcome measures to monitor dose adjustment of intravenous immunoglobulin (IVIg) therapy in patients with chronic inflammatory neuropathy (CIN). We assessed the adjustment of IVIg maintenance therapy in 20 patients (10 CIDP and 10 MMN) by regularly monitoring grip strength (GS) using a Martin Vigorimeter, RODS, and quality of life using the SF-36 questionnaire. These measures were regularly performed by the patient at home. We also assessed the extended MRC sumscore (eMRC sumscore) at each outpatient visit for IVIg infusion. We also enrolled 30 healthy controls to measure any possible training effect of GS with time and to analyze random fluctuation of GS. Clinically relevant change was detected by eMRC sumscore in 14 (93%) patients, by RODS in 11 (73%) patients, and by GS in 8 (53%) patients. Early sensitivity was greatest for RODS (73%), followed by GS (53%), and eMRC sumscore (27%). This differed from CIDP, with an early change in RODS in 100% of patients, and MMN with an early change in GS in 75%. None of the outcome measures alone was sufficient to detect clinically significant changes in all patients. Home monitoring of outcome measures objectively assisted clinical decision during individualization of IVIg treatment. We recommend a multimodal approach using different outcome measures to monitor the individual patient with CIN.

Comparison of the Jamar dynamometer and the Martin vigorimeter for grip strength measurements in a healthy elderly population.

Grip strength is considered to be a good indicator of upper limb strength. The Jamar dynamometer and the Martin vigorimeter are two instruments frequently used to assess grip strength in clinical and research settings. The purpose of this study was to compare these instruments for assessing grip strength in 360 people aged 60 to 94 years, randomly selected from the electoral list. Anthropometric data were also collected. Data analyses were done using the maximum value on 3 trials with each instrument. Although the Martin vigorimeter is a pressure measure implying a dynamic movement as opposed to the static strength measure of the Jamar dynamometer, results indicate a very high correlation between the two measures. Grip strength measured by the Jamar dynamometer is even more dependent on hand anthropometry than measurements with the Martin vigorimeter.

Grip strength in men and women aged 50-79 years is associated with non-vertebral osteoporotic fracture during 15 years follow-up: The Tromsø Study 1994-1995.

We aimed to explore whether low grip strength was associated with increased risk of non-vertebral osteoporotic fracture in the population-based Tromsø Study 1994-1995. Grip strength (bar) was measured by a Martin Vigorimeter and fractures were retrieved from the X-ray archives at the University Hospital of North Norway between 1994 and 2010. At baseline, weight and height were measured, whereas information on the other covariates were obtained through self-reported questionnaires. Cox regression was used to estimate the hazard ratio (HR) of fracture in age- and gender-specific quintiles of grip-strength, and per 1 SD lower grip strength. Similar analyses were done solely for hip fractures. Adjustments were made for age, height, body mass index (BMI), marital status, education, smoking, physical activity, use of alcohol, self-perceived health, and self-reported diseases. In 2891 men and 4002 women aged 50-79 years, 1099 non-vertebral osteoporotic fractures-including 393 hip fractures-were sustained during the median 15 years follow-up. Risk of non-vertebral osteoporotic fracture increased with declining grip strength: hazard ratios per SD decline was 1.22 (95% CI 1.05-1.43) in men and 1.09 (95% CI 1.01-1.18) in women. HR for fracture in lower vs. upper quintile was 1.58 (95% CI 1.02-2.45) in men and 1.28 (95% CI 1.03-1.59) in women. The association was most pronounced in men aged 50-64 years with HR = 3.39 (95% CI 1.76-6.53) in the lower compared to the upper quintile. The risk of non-vertebral osteoporotic fracture increased with declining grip-strength in both genders, particularly in men aged 50-64 years.

Grip Work Measurement with the Jamar Dynamometer: Validation of a Simple Equation for Clinical Use.

Previously, we developed and validated an easy test to measure muscle fatigability during sustained maximal handgrip contraction in older persons using a Martin Vigorimeter device. This study aimed at validating the equation to estimate grip work (GW) during sustained maximal handgrip contraction, by monitoring continuously the grip strength (GS) decay using a Jamar Dynamometer-like (JD) device. Cross sectional, explorative study. Data collection took place at The National Research Centre for the Working Environment in Copenhagen, Denmark. 962 subjects, belonging to a subgroup of the Copenhagen Aging and Midlife Biobank, were enrolled. GS was recorded continuously during sustained maximal contraction until it dropped to 50% of its maximum and fatigue resistance (FR, time to fatigue) was noted. GW, area under the force-time curve, was compared to its estimate which was calculated as GWestimated=GSmax*0.75*FR. Excellent correlation was found between GWestimated and GWmeasured (R²=0.98 p<0.001). The equation slightly overestimated GW by 6.04 kg*s (95% CI[-0.08, 12.15]) with a coefficient of variation method error of 6%. GW estimation is a valid parameter reflecting muscle work output during a sustained maximal grip effort in healthy middle-aged community-dwelling persons when using a JD. GW estimation is a promising outcome parameter in comprehensive geriatric assessment and its validation for commonly used instruments in geriatric practice will increase its clinical implementation.

Do More Recent Born Generations of Older Adults Have Stronger Grip? A Comparison of Three Cohorts of 66- to 84-Year-Olds in the Tromsø Study

BackgroundEvidence pertaining to whether more recent born generations of adults reaching old age have better physical capability than previous generations is scarce and inconclusive. We aimed to investigate birth cohort differences in grip strength.MethodsThe study comprised 5,595 individuals from the Tromsø study waves in 1994/1995, 2007/2008, and 2015/2016. Grip strength (bar) was measured using a Martin vigorimeter, and compared across three birth cohorts of 66- to 84-year-olds (born in: 1910–1929, 1923–1942, 1931–1949), as well as within narrower age bands to ensure nonoverlapping cohorts. Linear regression was applied, adjusted for age, education, smoking, physical activity, height, and weight.ResultsGrip strength increased across birth cohorts, and the increase was similar within narrower age bands and across genders. Overall, the increase in sex-adjusted mean grip strength when comparing the first and latest born cohorts, born 21 years apart, was 0.06 bar (95% CI 0.04, 0.07). Higher educational levels, and greater height and weight in the most recent born cohort explained 48% of this difference, while reduced smoking and physical inactivity in more recent born cohorts had little impact.ConclusionsOur findings suggest higher grip strength in more recent birth cohorts of older Norwegian adults, which can be partly attributed to higher education and greater height. This difference corresponded to a 5-year difference in grip strength; more recent born generations of 80-year-olds, therefore, have similar mean grip strength as 75-year-olds born one generation earlier.

Hip muscle and hand-grip strength to differentiate between older fallers and non-fallers: a cross-sectional validity study.

BackgroundHip muscle weakness in older people seems to be an influencing factor of falls. Currently, it is unclear which muscles out of the hip muscle group play an important role in older people. A validating process in the measurement regarding muscle strength related to falls is necessary before answering that question.ObjectiveFirstly, we aimed to investigate which hip muscle group strength shows an acceptable level of distinction between older adult fallers and non-fallers compared to a predefined external criterion regarding falling. Secondly, we aimed to compare the same outcomes and questions for hand-grip strength in relation to the same external criterion.DesignThis study was a cross-sectional validity study.MethodsThe maximum voluntary isometric strength (MVIS) and the rate of force generation of hip abductors (ABD), adductors, internal and external rotators, extensors, and flexors were measured with a dynamometer fixed to a custom-made frame as well as hand-grip strength with a Martin Vigorimeter in 60 older people aged over 65 years (38 females and 22 males).ResultsThe area under the curve (AUC) and the results of the mean decrease in Gini index assessed by random forest approach show that of all the assessed parameters, hip ABD MVIS showed the highest discriminative value regarding the chosen external criterion in older people (AUC ABD MVIS 0.825, 95% confidence interval: 0.712–0.938).ConclusionResults indicate that ABD MVIS is a useful measure to distinguish between older adult fallers and non-fallers regarding the chosen external criterion.

Towards wearable pressure sensors using multiwall carbon nanotube/polydimethylsiloxane nanocomposite foams

The use of multiwall carbon nanotube/polydimethylsiloxane (MWCNT/PDMS) nanocomposite in pressure sensors for healthcare and sports applications promises great benefits due to ease of its fabrication and mechanical robustness. In this study we investigate the effect of porosity in MWCNT/PDMS nanocomposites on its pressure sensing property. In contrast to its dense counterpart, MWCNT/PDMS nanocomposite foams exhibit negative pressure coefficient of resistance (NPCR) in which resistance decreases with applied pressure. This behavior is explained in terms of conducting paths formed between MWCNT protruding from walls of pores which are collapsing during compression. Normalized resistance change, computed from resistance data, increases at a slower rate for higher MWCNT loading in the range of variables investigated. A sports glove with integrated MWCNT/PDMS nanocomposites foam sensing elements (sensels) was fabricated. Maximal grip strengths determined using the sports glove are in agreement to those obtained using the Jamar dynamometer and Martin vigorimeter reported in the literature.

Optimizing the Use of Outcome Measures in Chronic Inflammatory Demyelinating Polyneuropathy

The challenges encountered during the assessment of patients with chronic inflammatory demyelinating polyneuropathy (CIDP) are many. Ideally, CIDP outcome measures capture impairments in disability, strength, and sensory dysfunction, and quality of life (QoL). A number of outcome measures have been validated for this purpose. Disability outcomes include the adjusted inflammatory neuropathy cause and treatment (INCAT) disability score, INCAT overall disability sum score (ODSS), and overall neuropathy limitations scale (ONLS). A more sensitive disability score, the inflammatory Rasch-built overall disability scale (I-RODS), has also been validated for use in clinical trials and may better capture clinically meaningful changes in those with CIDP. Strength and sensory impairment can be assessed in a number of ways, including the INCAT sensory subscore (ISS), Medical Research Council sum score, and Martin vigorimeter or Jamar dynamometer grip strength. However, the feasibility of applying and interpreting these measures during routine daily practice has been questioned. Furthermore, these outcome measures may not reflect other factors that can impair QoL in those affected by CIDP, such as pain and fatigue. A valid, reliable, and responsive composite measure that addresses all aspects of impairment faced by patients with CIDP remains an unmet need in clinical practice.

The Martin Vigorimeter Represents a Reliable and More Practical Tool Than the Jamar Dynamometer to Assess Handgrip Strength in the Geriatric Patient

BackgroundGeriatric patients with low skeletal muscle mass and strength generally have a relatively poor clinical outcome following acute illness. Therefore, it is recommended to routinely assess skeletal muscle mass and strength in patients admitted to the acute care geriatric ward. Handgrip strength is generally measured as a proxy for muscle strength and/or functional performance. ObjectiveTo compare the applicability and test-retest reliability of measuring handgrip strength using the Jamar dynamometer and the Martin Vigorimeter in geriatric patients during hospitalization. DesignA total of 96 geriatric patients (age 85 ± 5 y) admitted to the acute care geriatric ward participated in this study. Handgrip strength was assessed 3 times on 2 different occasions within 1 week of hospital admission using both the Jamar dynamometer and the Martin Vigorimeter. ResultsMaximal handgrip strength as determined over the 3 successive attempts performed on 2 occasions averaged 17 ± 7 kg and 35 ± 13 kPa when using the Jamar dynamometer and Martin Vigorimeter, respectively. Handgrip strength was significantly greater when using the dominant versus nondominant hand using both the Jamar dynamometer (17 ± 7 kg vs 16 ± 7 kg; P = .003) and Martin Vigorimeter (34 ± 12 kPa vs 33 ± 13 kPa; P = .022). Test-retest reliability showed an ICC of 0.94 and 0.92 when applying the Jamar dynamometer or Martin Vigorimeter, respectively (both P < .001). Furthermore, handgrip strength assessed with the Jamar and Martin Vigorimeter showed a strong correlation for both the first (ρ = 0.83, P < .001) and second measurement (ρ = 0.79, P < .001). Almost 80% of the geriatric patients needed help from nursing staff with transfer from bed to an arm-rested chair measuring handgrip strength with the Jamar dynamometer according to the Southampton protocol, which is not necessary when using the Martin Vigorimeter. ConclusionThe Martin Vigorimeter represents a reliable and more practical tool than the Jamar dynamometer to assess handgrip strength in the geriatric patient on admission to the acute geriatric ward.

Gender-specific associations between functional autonomy and physical capacities in independent older adults: Results from the NuAge study

BackgroundEven with healthy and active aging, many older adults will experience a decrease in physical capacities. This decrease might be associated with diminished functional autonomy. However, little is known about the physical capacities associated with functional autonomy in older women and men. ObjectiveThis study aimed to examine gender-specific associations between functional autonomy and physical capacities in independent older women and men. MethodsSecondary analyses were carried out using cross-sectional data from 652 women and 613 men who participated in the NuAge longitudinal study. The “functional autonomy measurement system” (SMAF) was used to evaluate functional autonomy. The physical capacities measured (tests used) were: biceps and quadriceps strength (Microfet dynamometer), grip strength (Martin vigorimeter), unipodal balance, changing position & walking (timed up and go), normal & fast walking (four-meter walking speed) and changing position (chair stand). Correlation and multiple linear regression analyses adjusted for age, depressive symptoms and body composition were performed. ResultsOn average, participants were aged 73 years and had mild to moderate functional autonomy loss. In women, after controlling for age, depressive symptoms and body composition, greater functional autonomy was best explained by faster changing position & walking skills and superior biceps strength (R2=0.46; p<0.001). After controlling for depressive symptoms, faster changing position & walking skills and better unipodal balance best explained greater functional autonomy in men (R2=0.21; p<0.001). ConclusionAccording to these results, physical capacities are moderately associated with functional autonomy among independent older adults, especially women.

Clinical impact of persistent hyperCKemia in a Norwegian general population: A case-control study

In this case-control study we assessed the clinical impact of persistent hyperCKemia in a Norwegian general population. HyperCKemia was defined according to the NORIP- references (women 35-210 U/L, men <50 years 50-400 U/L, and men ≥50 years 40-280 U/L). We compared the frequency of muscular symptoms and function, neuromuscular diseases and risk factors between 120 cases with persistent hyperCKemia and 130 age- and sex-matched controls with normal CK values, all recruited from the single-centre, population-based prospective Tromsø Study. The participants underwent a standardized interview assessing muscle symptoms, physical activity, use of statins and presence of other CK risk factors, prior to clinical neurological and neurophysiological examination. Knee extensor muscle strength (Cybex NORM dynamometer) and dominant hand grip strength (Martin Vigorimeter) was assessed. A total of 85 cases (71%) reported either muscle pain, muscle stiffness or cramps, compared to 70 controls (54%) (p=0.017) There were no differences in muscle strength between the groups. In men, weight, Body Mass Index and muscle symptoms were significantly higher in the group with persistent hyperCKemia. In women, no differences between the groups were detected. Use of statins was similar in cases and controls. We diagnosed 3 women with previously unknown myopathy, all in the group with persistent hyperCKemia. This study support that CK may be used as a marker of muscular symptoms in the general population.

Peripheral muscle weakness in RASopathies

RASopathies are a group of genetic conditions due to alterations of the Ras/MAPK pathway. Neurocutaneous findings are hallmark features of the RASopathies, but musculoskeletal abnormalities are also frequent. The objective was to evaluate handgrip strength in the RASopathies. Individuals with RASopathies (e.g., Noonan syndrome, Costello syndrome, cardio-facio-cutaneous [CFC] syndrome, and neurofibromatosis type 1 [NF1]) and healthy controls were evaluated. Two methods of handgrip strength were tested: GRIP-D Takei Hand Grip Dynamometer and the Martin vigorimeter. A general linear model was fitted to compare average strength among the groups, controlling for confounders such as age, gender, height, and weight. Takei dynamometer: handgrip strength was decreased in each of the syndromes compared with controls. Decreased handgrip strength compared with sibling controls was also seen with the Martin vigorimeter (P < 0.0001). Handgrip strength is decreased in the RASopathies. The etiology of the reduced muscle force is unknown, but likely multifactorial.