Is muscle strength ratio a criterion for diagnosis of site-specific muscle loss?

Ultrasound assessment of diaphragm and quadriceps muscles and its relationship with handgrip and respiratory muscle strength in patients with systemic sclerosis: a cross-sectional study

BACKGROUND

Muscle dysfunction may cause disability and reduce the quality of life of patients with systemic sclerosis (SSc) when compared to healthy individuals. However, the literature on the topic is scarce and uses several criteria for assessing muscle dysfunction in this population.

OBJECTIVES

To compare diaphragm and quadriceps muscle thickness, diaphragm mobility, and handgrip strength between patients with SSc and healthy individuals.

METHOD

This cross-sectional study included 16 patients with SSc and 16 self-reported healthy individuals matched for age. We assessed quadriceps and diaphragm thickness and diaphragmatic mobility (ultrasound), handgrip strength (hand-held dynamometer), and respiratory muscle strength (manovacuometer). Patients also responded to the Health Assessment Questionnaire Disability Index and the International Physical Activity Questionnaire.

RESULTS

Patients with SSc presented lower quadriceps thickness (p < 0.0001), diaphragmatic mobility (p = 0.01), handgrip (p < 0.0001), and respiratory muscle strength (p < 0.0001) than healthy individuals. A moderate positive correlation was observed between handgrip strength and quadriceps thickness in patients with SSc (rho = 0.576; p = 0.02).

CONCLUSIONS

Patients with SSc presented reduced quadriceps thickness, diaphragmatic mobility, handgrip, and respiratory muscle strength when compared to healthy individuals Also, handgrip strength was correlated with quadriceps thickness in patients with SSc, suggesting that loss of muscle mass accompanies loss of peripheral muscle strength group of patients. Key Points • SSc patients presented reduced quadriceps thickness and diaphragmatic mobility • SSc patients have reduced handgrip and respiratory muscle strength • Lower handgrip muscle strength correlated with lower quadriceps thickness.

Association of strength, power, and function with muscle thickness, echo intensity, and lean tissue in older males

Dual-energy X-ray absorptiometry (DXA) appendicular lean tissue is used to screen older adults for sarcopenia. However, emerging data indicates that ageing-related muscle atrophy largely occurs within specific muscles, which may be masked using appendicular lean tissue. Comparisons between appendicular lean tissue and site-specific measures of muscle in relation to strength and physical function are needed to advance our understanding of these features in the context of poor muscle function in aged adults. Our primary objective was to compare correlations between lean tissue and site-specific muscle characteristics in relation to strength and physical function in older males. Older males (≥65 years) were evaluated for muscle strength, physical function (6-minute walk and 30-second sit-to-stand), and muscle size (appendicular and site-specific) and composition (echo intensity) using DXA and ultrasound. Of the 32 older males (75.4 ± 7.9 years), 12 had low appendicular lean tissue. All DXA and ultrasound muscle characteristics were associated (r = 0.39 to 0.83, p < 0.05) with torque or power producing capabilities. Except for the knee flexors, no differences in correlation coefficients were observed between muscle thickness or regional lean tissue in relation to muscle strength. Neither DXA nor ultrasound muscle characteristics were associated with physical function. In older males, ultrasound-based muscle thickness and DXA lean tissue provided similar associations with strength. Novelty: Lean tissue and muscle thickness provide similar associations with strength. Muscle thickness can distinguish low and normal appendicular lean tissue in older adults.

Application of Muscle Thickness and Quality Measured by Ultrasound in Frailty Assessment in China

To explore the correlation between Fried Frailty Phenotype (FFP) and the muscle thickness and quality of local muscle, and to provide a reasonable basis for the application of ultrasound measurement in the frailty assessment. A total of 150 people (age ≥ 65 years, 58 women, 92 men) were included from the First Hospital Affiliated to Nanjing Medical University. They were divided into Normal group (40 cases), Prefrailty group (69 cases) and Frailty group (41 cases). The thickness and the quality of local muscle were detected by ultrasound. Participants in the prefrailty group had a higher grayscale value of the vastus lateralis muscle, indicating the deterioration of muscle quality. At the frailty stage, the muscle thickness and quality of the vastus lateralis muscle and the anterior tibialis muscle decreased significantly compared with the normal and the prefrailty group. Pearson's correlation analysis also showed FFP was negatively correlated with muscle thickness and quality of the lower limbs. In multiple regression model, FFP was positively associated with gray value (Vastus lateralis muscle:β =0.457, p < 0.001; Anterior tibialis muscle: β = 0.220, p = 0.037) and inversely associated with muscle thickness (Vastus lateralis muscle:β = −0.973, p = 0.031; Anterior tibialis muscle: β = −4.551, p = 0.004) in the frailty stage. Together, FFP was closely related to muscle thickness and quality, especially vastus lateralis muscle. Moreover, Muscle quality has deteriorated in the prefrailty stage, which is earlier than muscle thickness.

Energy Intake Is Highly Associated with Handgrip Strength in Community-Dwelling Elderly Adults

BACKGROUND

Handgrip strength (HGS) is used to assess muscle strength, which is an important indicator of health status in older adults.

OBJECTIVE

We evaluated associations of demographic, anthropometric, clinical, and nutritional factors with muscle strength in community-dwelling elderly adults.

METHODS

This population-based cross-sectional study employed the 2014-2015 Israeli Health and Nutrition Survey in the Elderly (n = 1039, age ≥65 y, 46.7% males, 9.9% Arabs). Trained personnel performed face-to-face interviews that focused on health and nutrition status, as well as anthropometric measurements and examinations. HGS was measured in the dominant hand 3 times using a digital grip strength dynamometer; the highest result was reported. Dietary intake data were collected using single-day 24-h recall. Multivariable logistic regressions were used to explore factors associated with low HGS (<27 kg for men and <16 kg for women).

RESULTS

HGS measurements were completed by 704 participants. Following adjustment for several factors, higher prevalence of low HGS was significantly associated with age (OR: 1.14; 95% CI: 1.11, 1.18), whereas decreased prevalence was associated with higher levels of education (OR: 0.55; 95% CI: 0.32, 0.94) and meeting physical activity recommendations (OR: 0.53; 95% CI: 0.31, 0.88); P < 0.05 for all. Incremental increases of 100 kcal/d in energy intake and of 1 cm in midarm circumference were associated with decreased prevalence of low HGS (OR: 0.95; 95% CI: 0.91, 0.99 and OR: 0.91; 95% CI: 0.85, 0.97, respectively; P < 0.01 for both). Associations were not found of low HGS with ethnicity, comorbidity, BMI, smoking, or alcohol consumption or with protein, carbohydrate, or fat intakes.

CONCLUSION

Energy intake, physical activity, midarm circumference, and education are associated with HGS in elderly Israeli adults. Further cohort studies are necessary to assess possible causal relations between these factors and HGS. Modifiable factors should be targeted in planning public health strategies for promoting a healthy aging population.

Associations Between Measures of Physical Activity and Muscle Size and Strength: A Systematic Review

Objective

To determine whether physical activity is associated with lower limb muscle size and strength within the general population.

Data Sources

Six databases were systematically searched from inception using 3 main constructs: lower extremity, muscle volume, and muscle strength.

Study Selection

Studies that measured physical activity (using either objective or subjective measurements), lower limb muscle size, and strength were included. Available discrete group data were standardized using previously published age- and sex-specific normative values prior to analysis.

Data Extraction

The final analysis included 47 studies from an initial yield of 5402 studies. Standardized scores for outcome measures were calculated for 97 discrete groups.

Data Synthesis

As anticipated, lower limb muscle size was positively correlated with lower limb muscle strength (r=0.26, P<.01; n=4812). Objectively measured physical activity (ie, accelerometry, pedometry) (n=1944) was positively correlated with both lower limb muscle size (r=0.30, P<.01; n=1626) and lower limb strength (r=0.24, P<.01; n=1869). However, subjectively measured physical activity (ie, questionnaires) (n=3949) was negatively associated with lower limb muscle size (r=–0.59, P<.01; n=3243) and lower limb muscle strength (r=–0.48, P<. 01; n=3882).

Conclusions

This review identified that objective measures of physical activity are moderately associated with lower limb muscle size and muscle strength and can, therefore, be used to predict muscle changes within the lower limbs associated with exercise-based rehabilitation programs.

Association between core stability and physical function, functional performance in patients with systemic sclerosis

OBJECTIVE

To investigate the association of core stability with physical function and functional performance in patients with systemic sclerosis (SSc).

METHODS

Forty patients who met the American College of Rheumatology / European League Against Rheumatism 2013 classification criteria for SSc were included in the cross-sectional study. For evaluation of core stability, trunk muscle endurance and trunk muscle strength were assessed. Trunk extensor and trunk flexor endurance tests were used for assessment of trunk muscle endurance. Trunk muscle strength was measured with a hand-held dynamometer and modified sit-up test. To measure physical function the Health Assessment Questionnaire Disability Index (HAQ-DI) and to measure functional performance 6-minute walking test (6MWT) and sit-to-stand test (STS) were used.

RESULTS

Patients with SSc had lower mean trunk extensor and flexor endurance test times (49.87 ± 30.81 and 32.17 ± 15.42 seconds, respectively), modified sit-up test repetition (17.42 ± 7.81) and trunk extensor and flexor muscle strength (7.48 ± 2.29 kg and 6.20 ± 1.68 kg, respectively) when compared to the reference values in healthy individuals. All measurements were used to evaluate core stability associated with HAQ-DI score, 6DMWT walking distance and STS test duration (all P < .05).

CONCLUSION

Patients with SSc have markedly reduced core stability and this negatively affects the physical function and functional performance. Therefore, this study highlights the importance of trunk muscle in patients with SSc. We suggest that not only upper-lower extremity muscles, but also trunk muscle strength and endurance should be measured and core stability exercises can be added to the training programs to maintain and/or improve physical functions and functional performance in SSc patients.

Correlation between SARC-F Score and Ultrasound-Measured Thigh Muscle Thickness in Older Hospitalized Cancer Patients

BACKGROUND

Strength, Assistance for walking, Rise from a chair, Climb stairs, and Falls (SARC-F) score is frequently used for screening the sarcopenia risk in older people. However, the agreement between SARC-F and loss of ultrasound-derived muscle thickness in hospitalized older cancer patients is unexplored.

OBJECTIVE

The primary objective was to evaluate the relationship between the SARC-F score and ultrasound-derived muscle thickness of rectus femoris and vastus intermedius in older hospitalised cancer patients. The secondary objective was to identify the presence of sarcopenia.

MEASUREMENTS

A cross-sectional study enrolled forty-one older hospitalised cancer patients ongoing chemotherapy or surgical treatment. Body weight (kg) was measured using a digital scale and height using a portable stadiometer to assess body mass index. SARC-F was performed to assess and classify sarcopenia risk (with (SARC-F: ≥4), without (SARC-F: <4). US-derived muscle thickness of rectus femoris and vastus intermedius was assessed using a portable ultrasound. Relationship between the SARC-F and muscle thickness was tested using Pearson´s correlation and Bland-Altman analyses.

RESULTS

Approximately, 46.3% of the patients presented sarcopenia and a lower non-significant muscle thickness of rectus femoris and vastus intermedius (SARC-F ≥4: 18.54±6.28 vs. SARC-F <4: 22.22±9.16 mm, p=0.07). There was a moderate negative correlation between SARC-F and muscle thickness (r=-0.40, p=0.004). Additionally, Bland-Altman plots no found systematic bias risk between SARC-F and ultrasound-derived muscle thickness.

CONCLUSIONS

Approximately, 46.3% of older hospitalized cancer patients presented sarcopenia. Additionally, we found a moderate inverse correlation and no systematic bias risk between SARC-F and ultrasound-measured muscle thickness.

Regional and total muscle mass, muscle strength and physical performance: The potential use of ultrasound imaging for sarcopenia

OBJECTIVE

To evaluate the relationship between the regional and total muscle mass, muscle strength and physical performance, and also to investigate the affected muscles, their strength and physical performance with aging.

METHODS

A total of 145 healthy subjects were included for the cross-sectional descriptive study. Demographic data were obtained, and body composition was consecutively assessed by anthropometric methods, bioelectrical impedance analysis and ultrasound (muscle thickness, fascicule length and pennation angle). Functional status was assessed using hand grip strength and gait speed measurements.

RESULTS

Abdominal and thigh muscles were thinner and triceps muscle was thicker in older subjects when compared with younger ones. Age and grip strength were significant predictors for physical performance. Gait speed, grip strength and regional muscle measurements decreased with age at higher rates (26-28%), skeletal muscle mass index was affected at a lower rate (15%).

CONCLUSIONS

Low muscle strength and regional muscle measurements should be used to confirm the diagnosis of sarcopenia.

Age-related effects on maximal and rapid hamstrings/quadriceps strength capacities and vertical jump power in young and older females

BACKGROUND AND AIMS

Declines in hamstrings and quadriceps maximal and rapid strength are commonly reported as a consequence of aging; however, few studies have investigated the influence of age on maximal and rapid hamstrings to quadriceps (H/Q) strength ratios. This study aimed to examine the effects of age on leg extension and flexion maximal and rapid torque production, H/Q strength ratios, and muscle power in healthy, young and old females.

METHODS

Fifteen young (21 ± 2 years) and 15 old (69 ± 7 years) females performed 3 isometric leg extension and flexion maximal voluntary contractions (MVCs), from which peak torque (PT), early (0-30 ms) and late (0-200 ms) phase rate of torque development (RTD), and PT and RTD H/Q strength ratios were extracted. Lower-body peak power output (P _max) was assessed through a vertical jump test.

RESULTS

P _max, PT, and early (RTD30) and late (RTD200) RTD variables of the leg extensors and flexors were lower (P ≤ 0.048) and PT and RTD200 H/Q strength ratios were higher (P ≤ 0.030) in the old compared to the younger females; however, no difference was observed for RTD30 H/Q (P = 0.300). There were also significant negative relationships in the older (r = -0.616 and -0.522; P = 0.014 and 0.046) but not the younger (r = 0.295 and -0.109; P = 0.286 and 0.698) females between P _max and RTD30 and RTD200 H/Q strength ratios.

CONCLUSION

The higher RTD200 H/Q ratio for the older females may contribute to the muscle power deficits often observed in elderly populations. Practitioners may use these findings to help identify older adults with low muscle power capacities and possibly overall functional decline.

Functional and Volumetric Analysis of the Pectoralis Major Muscle After Submuscular Breast Augmentation

BACKGROUND

Dual plane breast augmentation is a technical variation of the submuscular plane described as a technique that reduces contour deformities due to contraction of the pectoralis major muscle and lower risk of double-bubble deformity associated with breast ptosis. Despite improvement in the aesthetic aspect, there is still no consensus whether this technique affects the function of the pectoralis major muscle.

OBJECTIVES

The aim of this study was to correlate functional with volumetric changes associated with dissection of the muscle origin in submuscular breast augmentation.

METHODS

Thirty women who desired to undergo breast augmentation were selected prospectively and randomly allocated to 2 groups: 10 patients in the control group and 20 patients in the interventional group, who underwent submuscular breast augmentation. Magnetic resonance imaging and volumetric software were used to assess muscle volume and isokinetic dynamometry was used to assess function of the pectoralis major muscle. Preoperative measurements were compared with those at 3, 6, and 12 months after surgery.

RESULTS

Magnetic resonance imaging revealed significant decrease in muscle volume at 6 and 12 months follow-up. The isokinetic test conducted during adduction showed a significant difference in muscle strength between groups from baseline to the 12-month follow-up, and between the 3- and 12-month follow-up. No significant differences in muscle strength during abduction were observed from baseline to the 3-, 6-, and 12-month follow-up.

CONCLUSIONS

Submuscular breast augmentation reduced muscle strength during adduction 12 months after surgery, but without a significant correlation with volumetric muscle loss.

LEVEL OF EVIDENCE 2

Systemic sclerosis: Association between physical function, handgrip strength and pulmonary function

BACKGROUND

Systemic sclerosis (SSc) is a multisystem disease affecting the skin, respiratory system and skeletal muscles. In SSc patients, hand function disability is the major factor limiting daily activities.

AIM

To evaluate the association of physical function with handgrip strength and pulmonary function in SSc patients. A further aim was to assess the relationship between handgrip strength and pulmonary function in patients with SSc.

METHOD

A cross-sectional study in which 28 patients with SSc underwent isometric handgrip strength (IHGS) measurement and pulmonary function tests and completed the Health Assessment Questionnaire Disability Index (HAQ-DI) to measure physical function.

RESULTS

The HAQ-DI scores were associated with the IHGS (r_s = -0.599, P = 0.001) and pulmonary function parameters, particularly the diffusion capacity for carbon monoxide (DLco; r_s = -0.642, P = 0.0004).

CONCLUSION

In patients with SSc, the degree of physical disability is associated with both hand grip strength and pulmonary function. However, there is no relationship between handgrip strength and pulmonary function in these patients.

Kinematic analysis of tandem gait on a sine wave walkway

[Purpose] The purpose of this study was to ascertain the kinematic characteristics on a horizontal plane, including knee joint rotation, when walking with a tandem gait on a sine wave walkway. [Subjects and Methods] Eighteen healthy adults were enrolled as subjects in this study. They walked with a tandem gait on a sine wave walkway. A three-dimensional motion analysis system was used to record data and calculate the trunk, hip joint, and knee joint rotation angles. [Results] The rotation angle ranges for the trunk, hip joint, and knee joint were 23.3°, 53.3°, and 47.3°, respectively. The trunk generally rotated towards the direction of movement, and when turning left using the left leg as the pivot, the hip joint was internally rotated and the knee joint was externally rotated. In contrast, when making a directional change to the right using the left leg as the pivot, the hip joint was externally rotated and the knee joint was internally rotated. [Conclusion] Through tandem gait analysis on a sine wave walkway, knee joint rotation was found to be important in changes of direction.

Relationships of ultrasound measures of intrinsic foot muscle cross-sectional area and muscle volume with maximum toe flexor muscle strength and physical performance in young adults

[Purpose] To investigate the relationships between toe flexor muscle strength with (TFS-5-toes) and without (TFS-4-toes) the contribution of the great toe, anatomical and physiological muscle cross-sectional areas (CSA) of intrinsic toe flexor muscle and physical performance were measured. [Subjects] Seventeen men (82% sports-active) and 17 women (47% sports-active), aged 20 to 35 years, volunteered. [Methods] Anatomical CSA was measured in two intrinsic toe flexor muscles (flexor digitorum brevis [FDB] and abductor hallucis) by ultrasound. Muscle volume and muscle length of the FDB were also estimated, and physiological CSA was calculated. [Results] Both TFS-5-toes and TFS-4-toes correlated positively with walking speed in men (r=0.584 and r=0.553, respectively) and women (r=0.748 and r=0.533, respectively). Physiological CSA of the FDB was significantly correlated with TFS-5-toes (r=0.748) and TFS-4-toes (r=0.573) in women. In men, physiological CSA of the FDB correlated positively with TFS-4-toes (r=0.536), but not with TFS-5-toes (r=0.333). [Conclusion] Our results indicate that physiological CSA of the FDB is moderately associated with TFS-4-toes while toe flexor strength correlates with walking performance.

Appendicular lean mass and site-specific muscle loss in the extremities correlate with dynamic strength

BACKGROUND

Previous studies have reported the non-homogenous loss of muscle mass (site-specific muscle loss) with ageing, but this relationship to the loss of strength is not totally understood.

PURPOSE

To investigate the relationship between maximal dynamic strength and site-specific muscle mass of the thigh and upper arm.

METHODS

Thirty-five recreationally active men were separated into young-aged (YG, 20-39 years, n = 12), middle-aged (MG, 40-59 years, n = 13) and old-aged groups (OG, 60-75 years, n = 10). One-repetition maximum strength (1-RM; leg press, chest press, knee flexion, lat pull-down, and knee extension), muscle thickness (MTH, anterior and posterior thigh and upper arm) and appendicular lean mass (aLM) index were obtained from participants. Site-specific thigh MTH ratio was determined by dividing anterior thigh MTH (50% of thigh length) by posterior thigh MTH (50% of thigh length).

RESULTS

aLM index was not significantly different between age groups, but a significantly smaller site-specific MTH thigh ratio was found in the OG. Collapsed across age groups both site-specific thigh MTH ratio and aLM index were significantly correlated with leg press, knee extension and knee flexion1-RM strength (r = 0·390-0·699), but not with knee extension: knee flexion (KE:KF) 1-RM strength ratios (r = 0·037-0·081). Separated by age groups only aLM index was correlated with KE:KF 1-RM ratio for the OG (r = 0·780).

CONCLUSIONS

Site-specific thigh MTH ratio may be an important assessment tool in older individuals as it is different among age groups and is significantly related to dynamic maximal strength. However, maximal dynamic strength ratios appear to be less sensitive to differences in site-specific MTH ratios.

Association between toe grasping strength and accelerometer-determined physical activity in middle-aged and older women

[Purpose] To test the hypothesis that toe grasping strength is associated with daily physical activity in older adults. [Subjects] Fifty-seven Japanese women, aged 52-78 years, volunteered. [Methods] Toe grasping and knee extension strength were measured. Physical activity was also measured, using an accelerometer, and the total duration of each level of exercise intensity (light, moderate, and vigorous) and average step counts were calculated. Subjects were separated into two groups on the basis of accelerometer-determined step counts: LOW (n=28, <8000 steps/day) and HIGH (n=29, ≥8000 steps/day). [Results] Body mass index and body composition (% fat and fat-free mass) were similar between the two groups. Absolute and relative toe grasping strengths (divided by body weight) were greater in HIGH than in LOW. However, both absolute and relative knee extension strength were similar between the groups. Relative toe grasping and knee extension strength correlated with all 3 intensities of physical activity and average step count. After adjusting for age, the duration of light plus moderate physical activity and average step counts correlated to toe grasping strength but not to knee extension strength. [Conclusion] Our results suggest that toe grasping strength may be associated with the amount of light intensity daily physical activity.

Ultrasound assessment of hamstring muscle size using posterior thigh muscle thickness

Several studies have investigated the relationship between ultrasound-measured muscle thickness (MT) and individual muscle cross-sectional area (CSA) and muscle volume (MV) in extremity and trunk muscles; however, the hamstring muscle has not been studied. The purpose of this study was to examine the relationship between posterior thigh MT by ultrasound and the muscle CSA and MV of the hamstring obtained by magnetic resonance imaging (MRI). Ten young women aged 20-31 had MT measured by ultrasound at three sites on the medial anterior (50% of thigh length; TL) and posterior (50% and 70% of TL) aspects of the thigh. On the same day, a series of continuous muscle CSA along the thigh was measured by MRI. In each slice, the anatomical CSA of the hamstring (biceps femoris, semitendinosus and semimembranosus) and quadriceps muscle was analysed, and the CSAs at 50% and 70% of TL and maximal CSA of the hamstring (CSAmax ) were determined. MV was calculated by multiplying CSA by slice thickness. A significant correlation was observed between posterior 50% MT and 50% hamstring CSA (r = 0·848, P = 0·002) and between posterior 70% MT and 70% hamstring CSA (r = 0·679, P = 0·031). Posterior 50% MT (r = 0·732, P = 0·016) and 50% MTxTL (r = 0·873, P = 0·001) were also correlated to hamstring MV. Anterior:posterior 50% thigh MT ratio was correlated to MV ratio of quadriceps and hamstring muscles (r = 0·803, P = 0·005). Our results suggest that posterior thigh MT reflects hamstring muscle CSA and MV. The anterior:posterior MT ratio may serve as a surrogate for MV ratio of quadriceps and hamstring.