Handgrip Strength: A Comparison of Values Obtained From the NHANES and NIH Toolbox Studies

IMPORTANCE

Handgrip dynamometry is probably the most commonly used method to characterize overall human muscle strength.

OBJECTIVE

To compare and summarize grip strength measurements obtained from two population-based studies.

DESIGN

Secondary data analysis.

SETTING AND PARTICIPANTS

Data from (1) the 2011-2014 National Health and Nutrition Examination Survey (NHANES) with 13,918 participants and (2) the 2011 normative phase of the National Institutes of Health (NIH) Toolbox project with 3,594 participants.

OUTCOMES AND MEASURES

The NHANES values used were the mean and best of three trials; the NIH Toolbox value used was the one maximum trial after a practice trial.

RESULTS

General linear model analysis revealed that values obtained from the NIH Toolbox differed from NHANES best values but not from NHANES mean values. The analysis also indicated, regardless of the values used, that grip strength differed significantly between dominant and nondominant sides, males and females, and age groups. We provide updated reference values for handgrip strength.

CONCLUSIONS AND RELEVANCE

On the basis of these analyses, we summarize grip strength measures obtained from the NHANES and NIH Toolbox for side, gender, and age group strata. Reference values are essential to assist in the interpretation of testing results and clinical decision making.

A comparison of electronic and manual dynamometry and goniometry in patients with fracture of the distal radius and healthy participants

The purpose of this study was to assess the intra-rater and inter-rater reliability of electronic and manual dynamometry and goniometry in healthy volunteers, and the inter-instrument reliability in the assessment of healthy volunteers and patients recovering after a fracture of the distal radius. Grip strength, grip fatigue, pinch strength and range of motion were assessed in all participants with both the manual and electronic instruments by two physiotherapists and orthopaedic specialist trainee. The measures of dynamometry demonstrated excellent reliability (intra-class correlation coefficient >0.90), with the instruments found to be interchangeable with the exception of the grip fatigue. Variable intra-rater and inter-rater reliability was demonstrated with all planes of movement for the goniometry measures regardless of the instrument used. The results of this study support the continued use of dynamometry in the clinical setting, but raise questions regarding the use of goniometry measurements.

LEVEL OF EVIDENCE

Diagnostic level III.

Direct, quantitative clinical assessment of hand function: usefulness and reproducibility

Methods of assessing functional impairment in arthritic hands include pain assessments and disability scoring scales which are subjective, variable over time and fail to take account of the patients' need to adapt to deformities. The aim of this study was to evaluate measures of functional strength and joint motion in the assessment of the rheumatoid (RA) and osteoarthritic (OA) hand. Ten control subjects, ten RA and ten OA patients were recruited for the study. All underwent pain and disability scoring and functional assessment of the hand using measures of pinch/grip strength and range of joint motion (ROM). Functional assessments including ROM analyses at interphalangeal (IP), metacarpophalangeal (MCP) and wrist joints along with pinch/grip strength clearly discriminated between patient groups (RA vs. OA MCP ROM P<0.0001), pain and disability scales were unable to. In the RA there were demonstrable relationships between ROM measurements and disability (R2=0.31) as well as disease duration (R2=0.37). Intra-patient measures of strength were robust whereas inter-patient comparisons showed variability. In conclusion, pinch/grip strength and ROM are clinically reproducible assessments that may more accurately reflect functional impairment associated with arthritis.

Socio-economic position and its relationship to physical capacity among elderly people living in Jyväskylä, Finland: five- and ten-year follow-up studies

Socio-economic differences in self-reported disability are well described but much less is known about their associations with more objective measures of physical capacity. The aim was to study socio-economic differences in performance-based physical capacity in 75-year-old persons, examining changes in performance at five- and ten-year follow-up intervals. At the baseline 350 residents of the city of Jyväskylä, Finland, aged 75 were interviewed and 295 of them took part in clinical examinations. The corresponding figures at the five-year follow-up were 234 and 191 and at the ten-year follow-up 139 and 103. The statistical significance of differences in physical capacity between the socio-economic groups and genders were tested using ANOVA in univariate and repeated measures models and ANCOVA, with confounders added to the models. Generally, higher education and income were separately related to better maximal walking speed and vital capacity at every measurement point. In addition, higher income was related to better maximal isometric hand grip strength at both follow-ups. When education and income were in the same model, only income was related to physical capacity, almost without exception. Similarly, in the five- and ten-year follow-up periods, both education and income groups showed a parallel decline in physical capacity. The association between income and physical capacity remained even after adjusting for smoking, physical activity and number of chronic diseases. The results indicate that elderly people in disadvantaged socio-economic groups show lower levels of performance in almost all domains of physical capacity, but change in capacity over time does not differ significantly between either markers of socio-economic position.

Functional and biomechanical assessment of the normal and rheumatoid hand

OBJECTIVE

To assess hand function in accordance with its accepted definition and to compare the results of three different assessment techniques.

DESIGN

A clinical-type assessment was used together with measurement of pinch grip and three-dimensional biomechanical trials.

BACKGROUND

Traditional clinical assessment may not relate to a patient's actual hand function. If hand function is defined as "the ability to use the hand in daily activities" then it is more appropriate to measure the forces available for performing everyday tasks using biomechanical tests.

METHODS

Eight female patients with rheumatoid arthritis and eight control subjects were recruited for the study. Volunteers underwent a clinical-type assessment using a six-task activity board. Lateral pinch grip of both hands was measured using a custom-built transducer. Biomechanical trials were conducted using a 6 degree-of-freedom transducer and 6-camera motion analysis.

RESULTS

Functional differences between the two subject groups were apparent using all three methods of assessment. Pinch strength correlated well with the biomechanical trial data but results from the clinical-type assessment provided only a weak correlation.

CONCLUSIONS

Clinical-type assessments do not give an accurate measure of hand function. Pinch strength measurements can provide a cost-effective alternative to full biomechanical analysis.

RELEVANCE

Traditional functional assessment uses measurements of grip or pinch strength and range of motion together with a subjective assessment of activities of daily living. This study demonstrates that pinch strength measurements can provide an accurate measure of hand function. The results from activity-board trials do not reflect hand ability and are of limited use for hand evaluation.

Grip strength in end stage renal disease

The grip strength of 110 patients with end stage renal disease was measured. Their grip strength tended to be low compared with published norms. Significant correlations were found between the patients' grip strength and their gender, height, weight, and diabetic status. A regression equation including gender, height, and diabetic status as independent variables explained more than 40% of the variance in patients' grip strength.