Forearm Muscle Thickness Research Articles

New Perspectives for Low Muscle Mass Quantity/Quality Assessment in Probable Sarcopenic Older Adults: An Exploratory Analysis Study.

Low muscle mass quantity/quality is needed to confirm sarcopenia diagnosis; however, no validated cut-off points exist. This study aimed to determine the diagnostic accuracy of sarcopenia through muscle mass quantity/quality parameters, using the bioimpedance analysis (BIA), isokinetic, and ultrasound tools in probable sarcopenic community-dwelling older adults (≥60 years). Also, it aimed to suggest possible new cut-off points to confirm sarcopenia diagnosis. A cross-sectional exploratory analysis study was performed with probable sarcopenic and non-sarcopenic older adults. BIA, isokinetic, and ultrasound parameters were evaluated. The protocol was registered on ClinicalTrials.gov (NCT05485402). A total of 50 individuals were included, 38 with probable sarcopenia (69.63 ± 4.14 years; 7 men and 31 women) and 12 non-sarcopenic (67.58 ± 4.54 years; 7 men and 5 women). The phase angle (cut-off: 5.10° men, p = 0.003; 4.95° women, p < 0.001), peak torque (cut-off: 66.75 Newtons-meters (N-m) men, p < 0.001; 48.35 N-m women, p < 0.001), total work (cut-off: 64.00 Joules (J) men, p = 0.007; 54.70 J women, p = 0.001), and mean power (cut-off: 87.8 Watts (W) men, p = 0.003; 48.95 W women, p = 0.008) in leg extension, as well as the the forearm muscle thickness (cut-off: 1.41 cm (cm) men, p = 0.017; 0.94 cm women, p = 0.041), had great diagnostic accuracy in both sexes. The phase angle, peak torque, total work, and mean power in leg extension, as well as forearm muscle thickness, had great diagnostic accuracy in regard to sarcopenia, and the suggested cut-off points could lead to the confirmation of sarcopenia diagnosis, but more studies are needed to confirm this.

Longitudinal changes of grip strength and forearm muscle thickness in young children.

Grip strength is a marker of future health conditions and is mainly generated by the extrinsic flexor muscles of the fingers. Therefore, whether or not there is a relationship between grip strength and forearm muscle size is vital in considering strategies for grip strength development during growth. Thus, this study aimed to examine the association between changes in grip strength and forearm muscle thickness in young children. Two hundred eighteen young children (104 boys and 114 girls) performed maximum voluntary grip strength and ultrasound-measured muscle thickness measurements in the righthand. Two muscle thicknesses were measured as the perpendicular distance between the adipose tissue-muscle interface and muscle-bone interface of the radius (MT-radius) and ulna (MT-ulna). All participants completed the first measurement and underwent a second measurement one year after the first one. There were significant (P < 0.001) within-subject correlations between MT-ulna and grip strength [r = 0.50 (0.40, 0.60)] and MT-radius and grip strength [r = 0.59 (0.49, 0.67)]. There was no significant between-subject correlation between MT-ulna and grip strength [r = 0.07 (-0.05, 0.20)], but there was a statistically significant (P < 0.001) between-subject relationship between MT-radius and grip strength [r = 0.27 (0.14, 0.39)]. Although we cannot infer causation from the present study, our findings suggest that as muscle size increases within a child, so does muscle strength. Our between-subject analysis, however, suggests that those who observed the greatest change in muscle size did not necessarily get the strongest.

Assessment of Sarcopenia Using Muscle Ultrasound in Patients With Cirrhosis and Sarcopenic Obesity (AMUSE STUDY).

Sarcopenic obesity (SO) marks a confluence of 2 complex entities involving the muscle-liver-adipose tissue axis. Computed tomographic (CT) scan-derived skeletal muscle index (SMI) remains the gold standard for sarcopenia assessment in SO. However, it has intrinsic limitations of cost, radiation, and point of care applicability. We assessed the role of muscle ultrasound (US) in SO. A total of 52 patients with cirrhosis and obesity were assessed for sarcopenia using SMI. US assessment of thigh and forearm muscles was done to record quadriceps muscle thickness (QMT), quadriceps feather index (QMFI), forearm muscle thickness (FMT), and forearm feather index (FFI), respectively. Evaluated US parameters were correlated with SMI and assessed for diagnostic accuracy using the area under the curve. A total of 40 (76.9%) males and 12 (23.1%) females [mean age: 50.9y (43.8 to 53.5y)] were included. QMT [0.45cm/m2 (0.42 to 0.48cm/m2) vs. 0.67cm/m2 (0.63 to 0.70cm/m2)], QMFI [0.82cm/m2 (0.77 to 0.87cm/m2) vs. 1.12cm/m2 (1.06 to 1.19cm/m2)], FMT [0.19cm/m2 (0.17 to 0.20cm/m2) vs. 0.25cm/m2 (0.23 to 0.27cm/m2)], and FFI [0.38cm/m2 (0.35 to 0.412cm/m2) vs. 0.47cm/m2 (0.44 to 0.50cm/m2)] were significantly lower in patients with SO (P<0.01). A positive correlation with SMI was seen for all parameters in the entire cohort. The strongest correlation was exhibited by QMT (r=0.70) and QMFI (r=0.70) in males. The area under the curve of QMT, QMFI, FMT, and FFI were 0.98 (95% confidence interval: 0.96-1), 0.95 (0.89-1), 0.85 (0.75-0.96), and 0.80 (0.68-0.93), respectively. US-based assessment of sarcopenia has excellent diagnostic accuracy and correlates well with computed tomography-SMI in patients with SO. US may serve as an easy-to-use, point of care tool for assessing sarcopenia in SO with the advantage of repeated sequential assessment.

One-Year Handgrip Strength Change in Kindergarteners Depends upon Physical Activity Status.

Free play in kindergarten can be roughly divided into fine and gross motor activities, but the effects of these activities on improving handgrip strength are unknown. Therefore, we aimed to compare one-year changes in handgrip strength and forearm flexor muscle size in children separated by preferred play in a kindergarten. One hundred and eleven children were recruited from a local kindergarten. They underwent handgrip strength and forearm muscle thickness measurements, and 95 (49 boys and 46 girls) underwent a second measurement one year after the first measurement. Class teachers assessed the physical activity of everyone in their class after the second measurement. Using three evaluation scores by the class teachers, we divided children into three groups based on the children's preference to play in kindergarten (fine movement vs. gross motor movement). Handgrip strength did not change differently between groups across one year. However, children who liked active playing outside (i.e., gross motor activity) were stronger than others. Furthermore, children who like playing outside observed greater changes than the other groups in the ulna (right hand) and radius muscle thickness (left hand), suggesting that changes in forearm muscle size might be incongruent with changes in handgrip strength among the three activity groups.

Association of changes in grip strength with second digit length adjusted for fourth digit length in young children.

The factors involved in changes in grip strength (GS) during growth/development are not well known. Findings from cross-sectional studies have indicated that digit lengths are associated with physical fitness, including GS. This study aimed to investigate the association of changes in GS over 1 year and the second (2D) and fourth (4D) digit lengths in young children using the 4D as a covariate. One hundred and three young children (54 boys and 49 girls) performed maximum voluntary GS and ultrasound-measured forearm muscle thickness measurements in the right hand. All participants completed the first measurement and underwent a second measurement 1 year after the first one. The 2D and 4D were taken on the palmar surface of the outstretched right hand at the second measurement. The 2D was inversely associated with the change in GS (B = -2.1, p = 0.023) adjusted for all covariates. Girls had numerically lower adjusted changes in grip strength, although this was not statistically significant [-0.61 (-1.2, 0.02) kg]. When sex was removed from the model, the 2D remained inversely associated with the change in GS (B = -2.39, p = 0.011). Finally, when only adjusting for the 4D, the 2D was inversely associated with the change in GS (B = -3.07, p = 0.004). This study documented the association between changes in GS over 1 year and digit lengths in young children. The difference in children's digit length needs to be recognized as a factor involved in weak GS in children.

Impact of forearm pronation on ultrasound-measured forearm muscle thickness in children and adolescents

AbstractBackground and AimIt was unknown whether ultrasound-measured forearm muscle thickness was impacted by pronation of the forearm. The aim of this study was to investigate the influence of forearm pronation on two forearm muscle thicknesses (MT-ulna and MT-radius).Participants and MethodsFourteen healthy children and adolescents sat on a chair with their right arm comfortably on a table, and their hands were fixed to the board with elastic bands. The probe was placed perpendicularly over the forearm, and the angle of the board was then pronated in 5° increments from −10° to 30°. The average value of the two measures at each angle was used.ResultsThere was evidence that MT-ulna differed across measurement sites (F = 51.086, P &lt; 0.001). For example, the values of the MT-ulna were 2.58 (SD 0.40) cm in standard position (0°), 2.56 (SD 0.41) in −10°, 2.62 (SD 0.41) in 10°, 2.65 (SD 0.42) in 20°, and 2.71 (SD 0.43) in 30°. Follow-up tests found that all sites differed from each other except for −10° and −5° (P = 0.155) and 10° and 15° (P = 0.075). There was also evidence that the MT-radius differed across measurement sites (F = 22.07, P &lt; 0.001). Follow-up tests found that many but not all sites differed from each other.ConclusionOur results suggest that MT-ulna increases and MT-radius decreases due to forearm pronation from the standard position (0°). When determining the forearm position using the 95% limits of agreement, we recommend the forearm position within ±5° of the standard forearm position when measuring forearm MT.

Association of Hand Grip Strength with Ultrasound-derived Forearm Muscle Thickness and Echo Intensity in Young Indian Adults.

Muscle thickness (MT) quantification, which reflects the muscle function, can be measured using ultrasonography. Echo intensity (EI) quantified from the ultrasonography-derived skeletal muscle images reflects muscle quality. This study aimed to analyze the associations between handgrip strength, ultrasound-measured forearm MT, and EI in healthy young adults. Sixty healthy volunteers between the ages of 18 and 25 years participated in the study. Brightness mode ultrasonography (USG) was done to measure forearm radial and ulna MT. The EI was measured from an ultrasound image as a mean pixel value using a histogram in Adobe Photoshop. Individuals were tested for forearm handgrip strength using hand dynamometry. Males had higher forearm MT and handgrip strength compared to females. Handgrip strength had a significant positive correlation with forearm radius, ulna MT (r = 0.726, 0.757 and P < 0.01), and forearm circumference (r = 0.529 and P < 0.01) and a negatively correlation with subcutaneous fat thickness (r = -0.496 and P < 0.01) and EI (r = -0.618 and P < 0.01). Linear regression showed a significant correlation between MT, circumference, and EI with handgrip strength (r = 0.825 and P < 0.001). After adjustment for the other two parameters, the forearm MT correlated positively and EI negatively with handgrip strength. USG can be more easily used than other imaging methods in research and clinical setting as it is nonhazardous, less expensive, versatile, and provides results faster. Thus, USG measurements in skeletal muscle are useful for measuring MT and subcutaneous fat thickness. EI measurement can be a convenient and noninvasive method for assessing muscle quality.

The feasibility and reliability of measuring forearm muscle thickness by ultrasound in a geriatric inpatient setting: a cross-sectional pilot study

BackgroundGiven the potential benefits of introducing ultrasound in the clinical assessment of muscle disorders, this study aimed to assess the feasibility and reliability of measuring forearm muscle thickness by ultrasound in a geriatric clinical setting.MethodsCross-sectional pilot study in 25 participants (12 patients aged ≥ 70 years in an acute geriatric ward and 13 healthy volunteers aged 25–50 years), assessed by three raters. Muscle thickness measurement was estimated as the distance between the subcutaneous adipose tissue-muscle interface and muscle-bone interface of the radius at 30% proximal of the distance between the styloid process and distal insertion of the biceps brachii muscle of the dominant forearm. Examinations were repeated three times by each rater and intra- and inter-rater reliability was calculated. Feasibility analysis included consideration of technological, economic, legal, operational, and scheduling (TELOS) components.ResultsMean muscle-thickness measurement difference between groups was 4.4 mm (95% confidence interval [CI] 2.4 mm to 6.3 mm], p < 0.001). Intra-rater reliability of muscle-thickness assessment was excellent, with intraclass correlation coefficient (ICC) of 0.947 (95%CI 0.902 to 0.974), 0.969 (95%CI 0.942 to 0.985), and 0.950 (95%CI 0.907 to 0.975) for observer A, B, and C, respectively. Inter-rater comparison showed good agreement (ICC of 0.873 [95%CI 0.73 to 0.94]). Four of the 17 TELOS components considered led to specific recommendations to improve the procedure’s feasibility in clinical practice.ConclusionOur findings suggest that US is a feasible tool to assess the thickness of the forearm muscles with good inter-rater and excellent intra-rater reliability in a sample of hospitalized geriatric patients, making it a promising option for use in clinical practice.

The Measurement of Strength in Children: Is the Peak Value Truly Maximal?

It is unclear whether the measurement of maximum muscle strength in younger children can be performed accurately due to factors such as motivation and maturity (i.e., the ability to receive instruction). If there is a large change in a ratio between muscular strength and size from the youngest to the oldest, then this might provide some indication that the youngest may not have been able to voluntarily activate their muscles for reasons mentioned previously. The purpose of this study was to observe the ratio between handgrip strength (HGS) and forearm muscle thickness (MT) across differing ages in younger children. A total of 1133 preschool children (559 boys and 574 girls) between the ages of 4.5 and 6.5 years had MT and HGS measurements and calculated the ratio of HGS/MT (kg/cm). Linear regression was used to assess the impact of age and sex on the dependent variables of MT, HGS, and the HGS/MT ratio. The HGS/MT ratio increases moderately from age 4.5 to 6.5 in both boys and girls. However, the difference in this ratio was small between the age ranges in this sample. Our results indicate children as young as 4.5 may be accurately measured with the handgrip strength test.

SHORT TERM (24 HOURS) AND LONG TERM (1 YEAR) ASSESSMENTS OF RELIABILITY IN OLDER ADULTS: CAN ONE REPLACE THE OTHER?

There may be some individuals who do not adapt favorably to an exercise stimulus. This is most commonly determined by assessing the error of the measurement across two separate testing sessions separated by a short period of time. It has been recommended that this error be assessed over the same time frame as the intervention. We examined the 24-h test-retest reliability (n=18, aged 42 to 64 years) of forearm muscle thickness, handgrip strength, and “muscle quality” and compared that to the reliability observed when visits are separated by 1-year (n=80, aged 60 to 79 years). The measurement errors were greater in all measured variables following test-retest separated by 1-year than the test-retest separated by 24-hours. Our findings suggest that a time-matched control group is likely important to fully capture the error of the tester as well as the error associated with random biological variability within a timed intervention.

Ultrasound-Derived Forearm Muscle Thickness Is a Powerful Predictor for Estimating DXA-Derived Appendicular Lean Mass in Japanese Older Adults

To test the validity of published equations, anterior forearm muscle thickness (MT-ulna) of 158 Japanese older adults (72 men and 86 women) aged 50–79 y was measured with ultrasound. Appendicular lean soft tissue mass (aLM) was estimated from MT-ulna using two equations (body height without [eqn 1] and with [eqn 2]) previously published in the literature. Appendicular lean mass was measured using dual-energy X-ray absorption (DXA), and this method served as the reference criterion. There was a strong correlation between DXA-derived and ultrasound-estimated aLM in both equations (r = 0.882 and r = 0.944). Total error was 2.60 kg for eqn (1) and 1.38 kg for eqn (2). A Bland–Altman plot revealed that there was no systematic bias between DXA-derived and ultrasound-estimated aLM; however, eqn (1) overestimated aLM compared with DXA-derived aLM. Our results suggest that an ultrasound MT-ulna equation that includes body height is appropriate and useful for estimating aLM in Japanese adults.

Age-related change in handgrip strength in men and women: is muscle quality a contributing factor?

Age-related changes in muscle quality and muscle mass in the forearm, which relate to decline in handgrip strength (HGS), have not been reported. The purpose of this study was to investigate the relationships between age-related declines in HGS and loss of muscle thickness and/or muscle quality in the forearm of 613 adults (306 men and 307 women) aged 20-89. Anterior forearm muscle thickness (MT-ulna) and HGS were measured using an ultrasound and a hand dynamometer, respectively, in the dominant hand. Muscle quality (fMQ) was defined as a ratio of HGS to MT-ulna. HGS was similar among younger (ages 20-29, 30-39, and 40-49) groups and was progressively lower with increasing age in both sexes. MT-ulna was similar between ages 20-29 and 60-69 in men and between ages 20-29 and 70-79 in women. In men, MT-ulna was lower in ages 70-79 and 80-89 compared with other age groups. In women, MT-ulna was lower in ages 80-89 compared with ages 20-29 and 40-49. In both men and women, fMQ was identical among younger (ages 20-29, 30-39, and 40-49) groups. After that fMQ was progressively lower with age in both men and women. The results indicated that age-related decline in HGS is associated with fMQ, but it appears to be accelerated after the seventh decade due to muscle loss.

Protein Requirements in the Critically Ill: A Randomized Controlled Trial Using Parenteral Nutrition.

Current recommendations for higher protein/amino acid provision in the critically ill are based on weak evidence. This double-blinded randomized controlled trial aimed to compare standard amino acid intake with the higher level recommended as the minimum for critically ill patients. In total, 119 patients requiring parenteral nutrition (PN) in an intensive care unit (ICU) were randomized to receive blinded PN solutions containing amino acids at either 0.8 g/kg or 1.2 g/kg. Primary outcome was handgrip strength at ICU discharge. Secondary outcomes measured at study day 7 included handgrip strength, fatigue score (using the Chalder scale), and ultrasound measurements of muscle thickness at defined body sites. Analysis of covariance was used to control for age, sex, nutrition status (Subjective Global Assessment), Acute Physiology and Chronic Health Evaluation II (APACHE II) score, and baseline measurement. Actual amino acid delivery to the 2 groups was 0.9 and 1.1 g/kg respectively, averaged over the first 7 days. Grip strength at ICU discharge was not significantly different between groups (P =054) despite being improved at study day 7 in the group receiving the higher level of amino acids (mean [SD], 22.1 [10.1] vs 18.5 [11.8] kg, P =025). These patients also had less fatigue (Chalder score, mean [SD], 5.4 [2.2] vs 6.2 [2.2], P = .045) and greater forearm muscle thickness on ultrasound (mean [SD], 3.2 [0.4] vs 2.8 [0.4] cm, P < .0001). Nitrogen balance was significantly better at study day 3 but not at day 7. There was no difference between groups in mortality or length-of-stay measures. The higher level of amino acids was associated with small improvements in a number of different measures, supporting guideline recommendations for ICU patients. This trial was registered at Australian New Zealand Clinical Trials Registry (www.anzctr.org.au) as ACTRN12609000366257.

Handgrip strength dominance is associated with difference in forearm muscle size.

[Purpose] It is unknown whether handgrip strength dominance is related to the size of the forearm flexor muscles. The purpose of the present study was to investigate the relationship between side-by-side differences in handgrip strength and forearm muscle thickness. [Subjects] Thirty-one young women (26 right handed and 5 left handed) between the ages of 20 and 33 years volunteered to participate. [Methods] Two muscle thicknesses (forearm-ulna and forearm-radius muscle thicknesses) were measured using B-mode ultrasound at the anterior forearm on both sides of the body. Handgrip strength was also measured on both sides. [Results] The side-by-side difference in handgrip strength was 10.2% for the right-handed group, meaning the right hand was stronger. However, the left hand of the left-handed group was 7.8% stronger compared with their right hand. There was a significant positive correlation between side-by-side differences in handgrip strength and forearm-ulna muscle thickness (r = 0.765) and between handgrip strength and forearm-radius muscle thickness (r = 0.622). [Conclusion] Our results indicate that side-by-side differences in forearm muscle size may strongly contribute to handgrip strength dominance.

Association Between Forearm Muscle Thickness and Age-related Loss of Skeletal Muscle Mass, Handgrip and Knee Extension Strength and Walking Performance in Old Men and Women: A Pilot Study

Very little information is available concerning the relationship between handgrip strength and muscle size in the upper and lower extremities, especially the forearm muscle itself. To investigate the relationships among ultrasound-measured forearm muscle thickness from the radius and ulna bone interface with handgrip strength, knee extension strength, walking speed and absolute/relative total skeletal muscle mass (TMM), 32 Japanese men and 21 Japanese women ages 70–83 years had muscle thickness (MT) measured by ultrasound. In the forearm, two MTs (forearm-radius and forearm-ulna MT) were measured. TMM was estimated from an ultrasound-derived prediction equation. Handgrip-strength was significantly correlated with forearm-ulna MT in both men and women. There were no significant correlations between forearm MT and walking speed in either sex. In men, both forearm-radius and forearm-ulna MT were significantly correlated with TMM and TMM index. In women, a significant correlation was only observed between forearm-ulna MT and TMM index. Our results suggest that forearm-ulna MT may be a useful parameter for evaluating handgrip strength and TMM index in older Japanese men and women.

Strength Asymmetries In The Upper Limbs Of Right- And Left-handed Individuals

Motor skill tasks involving the upper body often show performance asymmetries favouring the dominant hand, and right-handers often show greater asymmetries than left-handers. However, very little is known about strength asymmetries in right- and left-handed people. PURPOSE: To determine the amount of strength asymmetry between the dominant (DOM) and non-dominant (NONDOM) upper limbs for various strength tasks in right- and left-handers. METHODS: Fifteen right-handers (RH) and fourteen left-handers (LH) completed seven maximal strength tasks (via a Norm or handgrip dynamometer), each for the DOM and NONDOM upper limb. Five tasks involved elbow flexion (EF) contractions: 1) Isometric (1.57 rad); 2) concentric fast (3.14 rad s-1); 3) concentric slow (0.52 rad s-1); 4) eccentric fast (3.14 rad s-1); and 5) eccentric slow (0.52 rad s-1); and two tasks involved isometric contractions of the wrist/hand: 1) ulnar deviation (UD) and 2) handgrip (HG). For each task, percent strength asymmetry scores were computed using the following formula: [(DOM strength score - NONDOM strength score) / stronger limb score] × 100. Positive scores indicate a DOM advantage. Activity of the agonist and antagonist muscles during maximal contractions was recorded via electromyography. DOM and NONDOM elbow flexor and medial forearm muscle thickness was measured via ultrasound. RESULTS: RH showed a significant DOM advantage for UD (+11.7 [SD 12.9] %; p<0.01) and HG (+8.1 [SD 8.1] %; p<0.01), whereas LH showed no significant strength asymmetry for hand tasks. No significant strength asymmetries were observed for EF tasks for either group. For both RH and LH, agonist and antagonist muscle activation was not significantly different between DOM and NONDOM for any task. There were no significant differences in muscle size between limbs. CONCLUSIONS: Right-handers exhibit greater strength asymmetry than left-handers for isometric hand strength tasks, but not for elbow flexor strength tasks. Since there was no significant difference in muscle size or peripheral muscle activation patterns, the neural basis of the dominant hand strength advantage in right-handers may be supraspinal. The lack of strength asymmetry in the upper limbs of left-handers might be due to more equal use of the limbs in tasks of daily living.

Relationship between Forearm Muscle Volume and Pressor Response during Static Handgrip in Elderly Women

The purpose of this study was to clarify the relationship between blood pressure (BP) response during static handgrip and forearm muscle thickness in 66 elderly women (60-81 years old). They performed static handgrip exercise (right hand) in a supine position. Exercise compromised a 30s static handgrip exercise separated by a 30s recovery. First and second loads were 1kgw and 2kgw, respectively, and thereafter the load was increased by 2kgw every 1min until the BP drifted upward from the previous load-BP relationship. Blood pressure was monitored on the finger of the left hand continuously. The critical load for notable BP elevation (BPcrit) was defined as an intersection point of two regression equations obtained from lower (L1) and higher (L2) intensity. Forearm muscle volume was estimated from muscle thickness measured by B-mode ultrasonography. BPcrit decreased significantly with age (r=-0.263, p<0.05). Forearm muscle thickness did not show a significant decrease in the age range of this study, whereas forearm muscle volume decreased significantly with age (r=-0.331, p<0.001). A negative correlation coefficient was obtained between muscle volume and slope of L2, indicating that the slope of L2 decreased as muscle volume increased. Consequently the blood pressure elevation at the lower intensity below BPcrit was independent of muscle thickness and volume; however, it was revealed that muscle volume affects the degree of BP elevation at the higher intensity.