Application of ultrasound for muscle assessment in sarcopenia: towards standardized measurements

Skeletal muscle estimation: A review of techniques and their applications

Quantifying skeletal muscle size is necessary to identify those at risk for conditions that increase frailty, morbidity, and mortality, as well as decrease quality of life. Although muscle strength, muscle quality, and physical performance have been suggested as important assessments in the screening, prevention, and management of sarcopenic and cachexic individuals, skeletal muscle size is still a critical objective marker. Several techniques exist for estimating skeletal muscle size; however, each technique presents with unique characteristics regarding simplicity/complexity, cost, radiation dose, accessibility, and portability that are important factors for assessors to consider before applying these modalities in practice. This narrative review presents a discussion centred on the theory and applications of current non-invasive techniques for estimating skeletal muscle size in diverse populations. Common instruments for skeletal muscle assessment include imaging techniques such as computed tomography, magnetic resonance imaging, peripheral quantitative computed tomography, dual-energy X-ray absorptiometry, and Brightness-mode ultrasound, and non-imaging techniques like bioelectrical impedance analysis and anthropometry. Skeletal muscle size can be acquired from these methods using whole-body and/or regional assessments, as well as prediction equations. Notable concerns when conducting assessments include the absence of standardised image acquisition/processing protocols and the variation in cut-off thresholds used to define low skeletal muscle size by clinicians and researchers, which could affect the accuracy and prevalence of diagnoses. Given the importance of evaluating skeletal muscle size, it is imperative practitioners are informed of each technique and their respective strengths and weaknesses.

Relationship between quadriceps femoris echotexture biomarkers and muscle strength and physical function in older adults with heart failure with preserved ejection fraction

BACKGROUND

Muscle wasting is pronounced in patients with heart failure with preserved ejection fraction (HFpEF). The quadriceps femoris echotexture biomarkers assessed by ultrasound (US) have not been studied in these patients.

OBJECTIVE

To describe echotexture biomarkers assessed by the US and to assess their relationship with sex, age, body mass index (BMI), self-reported outcomes, muscle strength and physical function in older adults with HFpEF.

METHODS

A cross-sectional study was conducted. Patients 70 years and older with HFpEF were included. The sex, age, BMI, and self-reported outcomes were collected. The US assessed muscle and subcutaneous fat tissue contrast, correlation, energy, homogeneity, and entropy at rest and maximal voluntary isometrical contraction (MVIC). The six-minute walk test (6MWT), the short physical performance battery (SPPB), the timed up and go test (TUG), the usual pace gait speed test (UGS), and the fast pace gait speed test (FGS) were used to assess physical function. The five-repetitions sit-to-stand test (5-STS) was performed to assess muscle strength. Bivariant Pearson correlations and subsequent multivariate linear regression analyses were conducted.

RESULTS

Seventy-two older adults with HFpEF [81.06 years, 29.13 BMI, and 55.60% females] were recruited. In women, relaxed and MVIC muscle energy and entropy explained 35.40% of the TUG variance; relaxed muscle entropy and MVIC muscle energy shared 24.00% of the UGS variance; relaxed and MVIC muscle entropy, MVIC muscle contrast and MVIC muscle energy explained 32.60% of the FGS variance, adjusted all the models by age and BMI.

CONCLUSIONS

Echotexture biomarkers are related to women's muscle strength and physical function, especially muscle energy, contrast, and entropy. Echotexture biomarkers assessed by the US could facilitate the management of older adults with HFpEF, monitor its progression and assess the effectiveness of treatments on the musculoskeletal structure.

TRIAL REGISTRATION

NCT03909919. April 10, 2019. Retrospectively registered.

Skeletal Muscle Texture Assessment Using Ultrasonography: Comparison with Magnetic Resonance Imaging in Chronic Kidney Disease

Skeletal muscle dysfunction is common in chronic kidney disease (CKD). Of interest is the concept of "muscle quality," of which measures include ultrasound-derived echo intensity (EI). Alternative parameters of muscle texture, for example, gray level of co-occurrence matrix (GCLM), are available and may circumvent limitations in EI. The validity of EI is limited in humans, particularly in chronic diseases. This study aimed to investigate the associations between ultrasound-derived parameters of muscle texture with MRI. Images of the thigh were acquired using a 3 Tesla MRI scanner. Quantification of muscle (contractile), fat (non-contractile), and miscellaneous (connective tissue, fascia) components were estimated. Anatomical rectus femoris cross-sectional area was measured using B-mode 2D ultrasonography. To assess muscle texture, first (i.e., EI)- and second (i.e., GLCM)-order statistical analyses were performed. Fourteen participants with CKD were included (age: 58.0 ± 11.9 years, 50% male, eGFR: 27.0 ± 7.4 ml/min/1.73m2, 55% Stage 4). Higher EI was associated with lower muscle % (quadriceps: β = -.568, p = .034; hamstrings: β = -.644, p = .010). Higher EI was associated with a higher fat % in the hamstrings (β = -.626, p = .017). A higher angular second moment from GLCM analysis was associated with greater muscle % (β = .570, p = .033) and lower fat % (β = -.534, p = .049). A higher inverse difference moment was associated with greater muscle % (β = .610, p = .021 and lower fat % (β = -.599, p = .024). This is the first study to investigate the associations between ultrasound-derived parameters of muscle texture with MRI. Our preliminary findings suggest ultrasound-derived texture analysis provides a novel indicator of reduced skeletal muscle % and thus increased intramuscular fat.

Low handgrip strength is related to elevated echogenicity in patients with chronic kidney disease: A pilot, cross-sectional and exploratory study

OBJECTIVES

Evaluate associations between triceps braqui muscle ultrasound measures (TB US) and handgrip strength (HGS), and the sensibility of TB US for low HGS in non-dialysis-dependent chronic kidney disease (nd-CKD) patients.

PARTICIPANTS AND METHODS

This pilot, cross-sectional, and exploratory study evaluated TB cross-sectional images from A-mode US and processed by FIJI-Image J to obtain muscle thickness (MT), echogenicity (EI), cross-sectional area (CSA), pennation angle (PA), and fascicle length (Lf) associating them with absolute HGS by simple and, multiple linear regression. The HGS was normalized to body mass index (BMI) and separated into low HGS (HGS/BMI≤10p according to sex and age) and adequate HGS (HGS/BMI>10p) groups. The body composition was from multifrequency bioimpedance. ROC analysis verified the TB US diagnostic accuracy to low HGS.

RESULTS

Were included 42 (21M/21F) adults with 65.5 (60-70) y median age, 47.22% in 3b CKD stage. The low HGS group (45.23%) showed a higher fat mass (FM), TB muscle medium head's PA, and EI than adequate HGS (p<0.05). In crude model, a pixels increase in EI was associated with a 0.452kgf HGS reduction (p=0.019); adjusted for sex, age, and FM, a one-unit increase in EI was associated with a 0.510kgf HGS reduction (p=0.011). The EI also showed moderate diagnostic accuracy (AUC=0.730; CI 95%=0.589; 0.919) to low HGS and a sensitivity of 86.9% (cutoff≥13.52 pixels).

CONCLUSION

In nd-CKD patients, of all measurements from US, the EI was the most associated with HGS, and the only one sensitive to low HGS diagnosis.

Ultrasound Cut-Off Values for Rectus Femoris for Detecting Sarcopenia in Patients with Nutritional Risk

BACKGROUND

A nationwide, prospective, multicenter, cohort study (the Disease-Related caloric-protein malnutrition EChOgraphy (DRECO) study) was designed to assess the usefulness of ultrasound of the rectus femoris for detecting sarcopenia in hospitalized patients at risk of malnutrition and to define cut-off values of ultrasound measures.

METHODS

Patients at risk of malnutrition according to the Malnutrition Universal Screening Tool (MUST) underwent handgrip dynamometry, bioelectrical impedance analysis (BIA), a Timed Up and Go (TUG) test, and rectus femoris ultrasound studies. European Working Group on Sarcopenia in Older People (EWGSOP2) criteria were used to define categories of sarcopenia (at risk, probable, confirmed, severe). Receiver operating characteristic (ROC) and area under the curve (AUC) analyses were used to determine the optimal diagnostic sensitivity, specificity, and predictive values of cut-off points of the ultrasound measures for the detection of risk of sarcopenia and probable, confirmed, and severe sarcopenia.

RESULTS

A total of 1000 subjects were included and 991 of them (58.9% men, mean age 58.5 years) were evaluated. Risk of sarcopenia was detected in 9.6% patients, probable sarcopenia in 14%, confirmed sarcopenia in 9.7%, and severe sarcopenia in 3.9%, with significant differences in the distribution of groups between men and women (p < 0.0001). The cross-sectional area (CSA) of the rectus femoris showed a significantly positive correlation with body cell mass of BIA and handgrip strength, and a significant negative correlation with TUG. Cut-off values were similar within each category of sarcopenia, ranging between 2.40 cm2 and 3.66 cm2 for CSA, 32.57 mm and 40.21 mm for the X-axis, and 7.85 mm and 10.4 mm for the Y-axis. In general, these cut-off values showed high sensitivities, particularly for the categories of confirmed and severe sarcopenia, with male patients also showing better sensitivities than women.

CONCLUSIONS

Sarcopenia in hospitalized patients at risk of malnutrition was high. Cut-off values for the better sensitivities and specificities of ultrasound measures of the rectus femoris are established. The use of ultrasound of the rectus femoris could be used for the prediction of sarcopenia and be useful to integrate nutritional study into real clinical practice.

Uncovering sarcopenia and frailty in older adults by using muscle ultrasound-A narrative review

Muscle ultrasound is a valuable non-invasive and cost-effective method in assessing muscle mass and structure, both of which are significant indicators for the development of sarcopenia and frailty in elderly individuals. Sarcopenia refers to the loss of muscle mass and strength that occurs with age, whereas frailty is a complex geriatric syndrome characterized by reduced physical function and an increased susceptibility to negative health outcomes. Both conditions are prevalent in older adults and are associated with higher risks of falls, disability, and mortality. By measuring muscle size and structure and several other ultrasound parameters, including muscle thickness, cross-sectional area, echogenicity (brightness in the ultrasound image), pennation angle, and fascicle length ultrasound can assist in identifying sarcopenia and frailty in older adults. In addition, ultrasound can be used to evaluate muscle function such as muscle contraction and stiffness, which may also be affected in sarcopenia and frailty. Therefore, muscle ultrasound could lead to better identification and tracking of sarcopenia and frailty. Such advancements could result in the implementation of earlier interventions to prevent or treat these conditions, resulting in an overall improvement in the health and quality of life of the elderly population. This narrative review describes the benefits and challenges when using ultra-sound for the evaluation of frailty and sarcopenia.

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

BACKGROUND

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.

METHODS

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).

RESULTS

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.

CONCLUSIONS

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.

Investigating the effects of synbiotic supplementation on functional movement, strength and muscle health in older Australians: a study protocol for a double-blind, randomized, placebo-controlled trial

BACKGROUND

Aging has been associated with a progressive loss of skeletal muscle quality, quantity and strength, which may result in a condition known as sarcopenia, leading to a decline in physical performance, loss of independence and reduced quality of life. While the cause of impaired physical functioning observed in elderly populations appears to be multifactorial, recent evidence suggests that age-associated alterations in gut microbiota could be a contributing factor. The primary objective will be to assess the effects of a dietary synbiotic formulation on sarcopenia-related functional outcomes such as handgrip strength, gait speed and physical performance within older individuals living independently. The secondary objective will be to examine associations between changes in gut microbiota composition, functional performance and lean muscle mass.

METHODS

Seventy-four elderly (60-85 years) participants will be randomized in a double-blind, placebo-controlled fashion to either an intervention or control group. The intervention group (n = 37) will receive oral synbiotic formulation daily for 16 weeks. The control group (n = 37) will receive placebo. Assessments of physical performance (including Short Physical Performance Battery, handgrip strength and timed up-and-go tests) and muscle ultrasonography will be performed at 4 time points (baseline and weeks 8, 16 and 20). Likewise, body composition via bioelectric impedance analysis and blood and stool samples will be collected at each time point. Dual-energy X-ray absorptiometry will be performed at baseline and week 16. The primary outcomes will be between-group changes in physical performance from baseline to 16 weeks. Secondary outcomes include changes in body composition, muscle mass and architecture, fecal microbiota composition and diversity, and fecal and plasma metabolomics.

DISCUSSION

Gut-modulating supplements appear to be effective in modifying gut microbiota composition in healthy older adults. However, it is unclear whether these changes translate into functional and/or health improvements. In the present study, we will investigate the effects of a synbiotic formulation on measures of physical performance, strength and muscle health in healthy older populations.

TRIAL REGISTRATION

This study was prospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12622000652774) in May 2022.

Body composition assessment with ultrasound muscle measurement: optimization through the use of semi-automated tools in colorectal cancer

Colorectal cancer (CRC) is a disease with a high prevalence and major impact on global health. Body composition (BC) data are of great importance in the assessment of nutritional status. Ultrasound (US) is an emerging, accessible and non-invasive technique that could be an alternative when it is not feasible to perform computed tomography (CT). The aim of this study is to evaluate the correlation between CT, as a reference technique, and US of the rectus femoris (RF) as a "proof of concept," in a cohort of patients with CRC and assess the optimisation of results obtained by US when performed by our new semi-automated tool. A single-centre cross-sectional study including 174 patients diagnosed with CRC and undergoing surgery was carried out at the Vall d'Hebron Hospital. We found a strong correlation between CT and US of the RF area (r = 0.67; p < 0.005). The latter, is able to discriminate patients with worse prognosis in terms of length of hospital stay and discharge destination (AUC-ROC = 0.64, p 0.015). These results improve when they are carried out with the automatic tool (area AUC-ROC = 0.73, p 0.023), especially when normalised by height and eliminating patients who associate overflow. According to our results, the US could be considered as a valuable alternative for the quantitative assessment of muscle mass when CT is not feasible. These measurements are improved when measuring software is applied, such as "Bat" software.

Development of Continuous Assessment of Muscle Quality and Frailty in Older Patients Using Multiparametric Combinations of Ultrasound and Blood Biomarkers: Protocol for the ECOFRAIL Study

BACKGROUND

Frailty resulting from the loss of muscle quality can potentially be delayed through early detection and physical exercise interventions. There is a demand for cost-effective tools for the objective evaluation of muscle quality, in both cross-sectional and longitudinal assessments. Literature suggests that quantitative analysis of ultrasound data captures morphometric, compositional, and microstructural muscle properties, while biological assays derived from blood samples are associated with functional information.

OBJECTIVE

This study aims to assess multiparametric combinations of ultrasound and blood-based biomarkers to offer a cross-sectional evaluation of the patient frailty phenotype and to track changes in muscle quality associated with supervised exercise programs.

METHODS

This prospective observational multicenter study will include patients aged 70 years and older who are capable of providing informed consent. We aim to recruit 100 patients from hospital environments and 100 from primary care facilities. Each patient will undergo at least two examinations (baseline and follow-up), totaling a minimum of 400 examinations. In hospital environments, 50 patients will be measured before/after a 16-week individualized and supervised exercise program, while another 50 patients will be followed up after the same period without intervention. Primary care patients will undergo a 1-year follow-up evaluation. The primary objective is to compare cross-sectional evaluations of physical performance, functional capacity, body composition, and derived scales of sarcopenia and frailty with biomarker combinations obtained from muscle ultrasound and blood-based assays. We will analyze ultrasound raw data obtained with a point-of-care device, along with a set of biomarkers previously associated with frailty, using quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Additionally, we will examine the sensitivity of these biomarkers to detect short-term muscle quality changes and functional improvement after a supervised exercise intervention compared with usual care.

RESULTS

At the time of manuscript submission, the enrollment of volunteers is ongoing. Recruitment started on March 1, 2022, and ends on June 30, 2024.

CONCLUSIONS

The outlined study protocol will integrate portable technologies, using quantitative muscle ultrasound and blood biomarkers, to facilitate an objective cross-sectional assessment of muscle quality in both hospital and primary care settings. The primary objective is to generate data that can be used to explore associations between biomarker combinations and the cross-sectional clinical assessment of frailty and sarcopenia. Additionally, the study aims to investigate musculoskeletal changes following multicomponent physical exercise programs.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05294757; https://clinicaltrials.gov/ct2/show/NCT05294757.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/50325.

Ultrasound Evaluation of Sarcopenia in Patients with Hepatocellular Carcinoma: A Faster and Easier Way to Detect Patients at Risk

The condition of sarcopenia, defined as a progressive loss of musculoskeletal mass and muscular strength, is very common in patients with hepatocellular carcinoma (HCC) and presents a remarkable association with its prognosis. Thus, the early identification of sarcopenic patients represents one of the potential new approaches in the global assessment of HCC, and there is increasing interest regarding the potential therapeutic implications of this condition. The gold standard for the quantification of muscle mass is magnetic resonance imaging (MRI) or computed tomography (CT), but these techniques are not always feasible because of the high-cost equipment needed. A new possibility in sarcopenia identification could be muscle ultrasound examination. The measurement of specific parameters such as the muscle thickness, muscular fascicles length or pennation angle has shown a good correlation with CT or MRI values and a good diagnostic accuracy in the detection of sarcopenia. Recently, these results were also confirmed specifically in patients with chronic liver disease. This review summarizes the role of imaging for the diagnosis of sarcopenia in patients with HCC, focusing on the advantages and disadvantages of the diagnostic techniques currently validated for this aim and the future perspectives for the identification of this condition.

Ultrasound for measurement of skeletal muscle mass quantity and muscle composition/architecture in critically ill patients: A scoping review on studies' aims, methods, and findings

AIMS

This scoping review aimed to identify, explore, and map the objectives, methodological aspects, and results of studies that used ultrasound (US) to assess skeletal muscle (SM) in critically ill patients.

METHODS

A scoping review was conducted according to the Joanna Briggs Institute's methodology. All studies that evaluated SM parameters from the US in patients admitted to the intensive care unit (ICU) were considered eligible. We categorized muscle thickness and cross-sectional area as parameters for assessing SM quantity, while echogenicity, fascicle length, and pennation angle analysis were used to evaluate muscle "quality" (composition/architecture). A literature search was conducted using four databases for articles published until December 2022. Independent reviewers selected the studies and extracted data. Descriptive statistics were calculated to present the results.

RESULTS

A total of 107 studies were included, the majority of which were prospective cohort studies (59.8 %) conducted in general ICUs (49.5 %). The most frequent objective of the studies was to evaluate SM quantity depletion during the ICU stay (25.2 %), followed by determining whether a specific intervention would modify SM (21.5 %). Most studies performed serial SM evaluations (76.1 %). The rectus femoris muscle thickness was evaluated in most studies (67.9 %), followed by the rectus femoris cross-sectional area (54.3 %) and the vastus intermedius muscle thickness (40.2 %). The studies demonstrated the feasibility and reproducibility of US for SM evaluation, especially related to quantitative parameters. Most studies (70.3 %) reported significant SM quantity depletion during hospitalization. However, the accuracy of the US in measuring SM varied across the studies.

CONCLUSIONS

The lack of detailed description and standardization in the protocols adopted by the studies included in this scoping review precludes the translation of the evidence related to US for SM assessment into clinical practice.

The Role of Ultrasound Muscle Parameters for Myosteatosis and Myofibrosis Measurement in Young, Older, and Obese Subjects

OBJECTIVES

The aim of the study was to compare quantitative and qualitative ultrasound parameters between healthy young adults and post-acute hospitalized older adults with and without physical disability, as well as between normal weight and overweight/obese persons.

DESIGN

Cross-sectional observational study.

SETTING AND PARTICIPANTS

A total of 120 individuals were recruited: 24 healthy young adults, 24 normal weight and 24 overweight/obese community-dwelling adults, and 48 post-acute hospitalized older adults with different degrees of functional autonomy.

METHODS

The rectus femoris cross-sectional area (CSA), subcutaneous adipose tissue (SCAT) thickness, echogenicity, strain elastography, and compressibility were measured with ultrasound echography.

RESULTS

Post-acute older adults with a good level of autonomy showed higher echogenicity, a higher compressibility index and elastometry strain, and lower rectus femoris thickness and CSA as compared with young persons. Post-acute individuals with physical disability showed lower echogenicity and a greater stiffness compared with their still autonomous counterparts. Normal weight individuals showed lower stiffness as evaluated with elastometry and a lower SCAT thickness, as compared with individuals with age-matched overweight or obesity. From multiple regression analyses, using CSA as an independent variable, an inverse association with female sex and age was observed, explaining 16% and 51% of variance. Echogenicity was directly associated with age (34% of variance) and with the Barthel index (6% of variance). Elastometry showed association with age and body mass index (BMI), 30% and 16% of variance, respectively. Considering compressibility as a dependent variable, a direct association with age and an inverse association with BMI were observed, with 5% and 11% of variance respectively.

CONCLUSIONS AND IMPLICATIONS

Muscle mass decreases with age and with physical disability. Echogenicity, which increases with age and disability level, seems to be associated with myofibrosis. Conversely, elastometry seems useful in the characterization of muscle quality in overweight or obese individuals and as a reliable indirect measure of myosteatosis.

Combined ultrasound of m. quadriceps and diaphragm to determine the occurrence of sarcopenia and prolonged ventilation in a COVID-19 ICU cohort: The COVID-SARCUS trial

OBJECTIVE

The aim of this study was to determine the development of sarcopenia in a COVID-19 intensive care unit population by sequential quadriceps and diaphragm ultrasound and its relationship with hospital outcomes.

METHODS

We assessed muscle thickness, cross-sectional area, fascicle length, pennation angle, and echo intensity within 48 h after intubation, at days 5 and 10 and at discharge from the intensive care unit in 30 critically ill patients with confirmed COVID-19.

RESULTS

A different evolution of muscle thickness of the diaphragm and m. rectus femoris was observed; the changes between the two muscles were not correlated (Pearson's χ2 3.91, P = 0.419). The difference in muscle thickness was linked to the outcome for both m. rectus femoris and diaphragm, with the best survival seen in the group with stable muscle thickness. The greatest loss of muscle thickness occurred between days 5 and 10. The echo intensity was higher in the patients with increased muscle thickness, who also had a worse prognosis. There was a correlation between cross-sectional area on day 5 and handgrip strength (r = 0.290, P = 0.010). Only 31% of patients were able to return to their preadmission residence without any additional rehabilitation.

CONCLUSIONS

Muscle atrophy and decline in muscle strength appear in the earliest stages after admission to the intensive care unit and are related to functional outcome.

The relationship between urinary incontinence and abdominal muscle thickness in community-dwelling older women undergoing comprehensive geriatric assessment

PURPOSE

Urinary incontinence (UI) is one of the most common geriatric syndromes in older adults, especially in women. The aim of this study is to show the relationship between urinary incontinence and abdominal muscle thickness measured by muscle ultrasonography (US) in community-dwelling older women adults.

METHODS

Eighty-seven community-dwelling older women participated in our study. The presence and the type of UI were recorded. Clinical and demographic characteristics were collected, and a comprehensive geriatric assessment was performed on all participants. Abdominal muscle layer thicknesses were evaluated with muscle US.

RESULTS

The prevalence of UI was 55.2% (n = 48) of the study population. The median [IQR] age of the patients in the UI group was 73.0 [69.0-77.5] years and it was 69.0 [67.0-73.0] years in patients without UI (p = 0.007). Abdominal muscle thicknesses were measured smaller in patients with UI than those without UI except for internal oblique muscle thickness. The median [IQR] rectus abdominis muscle thickness was lower in patients with UI than in patients without UI, and the difference was statistically significant (p < 0.003). RA muscle was associated with UI regardless of age, polypharmacy, malnutrition, and frailty (OR: 0.58; 95% CI 0.38-0.89; p = 0.01).

CONCLUSIONS

We have shown that UI was independently related to the rectus abdominis muscle thickness, which may reflect the function and mass of the pelvic floor muscles.

Muscle ultrasound and its application to point-of-care ultrasonography: a narrative review

Technological advances of hand-held ultrasound devices and educational programmes for their use, such as point-of-care ultrasonography (POCUS) training, have contributed to the increasing application of these devices in clinical practice. With the greater impact of frailty and sarcopenia in aging societies, attention is being focused on the use of ultrasound for skeletal muscle assessment. In this narrative review, we discuss how ultrasound can be applied to skeletal muscle assessment, especially that of the quadriceps muscle, in clinical practice. Muscle thickness by ultrasound has been shown to have good reliability and validity for the evaluation of muscle size, and echo intensity has been used to evaluate muscle quality. Muscle ultrasound has not only been useful to diagnose sarcopenia in various settings, but has also been validated to predict health-related outcomes such as death and functional disability. Recommended methods for muscle ultrasound was published recently, and the results of future studies are expected to be comparable. Although several challenging issues with muscle ultrasound remain, if it could be incorporated into educational programmes such as POCUS training, more clinicians may be able to use ultrasound for skeletal muscle assessment in the future.KEY MESSAGESThe evolution of hand-held ultrasound devices enables physicians to perform ultrasound at the bedside as part of regular medical examinations.Muscle ultrasound is considered an effective tool for evaluating muscle size and quality, and has been studied in various settings.More clinicians may be able to evaluate skeletal muscle assessment with the development of educational programmes on muscle ultrasound in the future.

Variability in Cross-Sectional Muscle Atrophy: Insights From the Central Rectus Femoris

BACKGROUND AND PURPOSE

This study aimed to evaluate the non-uniformity of cross-sectional areas in atrophic muscles using the central aponeurosis (CA) as a marker for the central region of the rectus femoris (RF).

METHODS

We enrolled 51 consecutively admitted patients (102 limbs) with aortic valve stenosis who were scheduled for elective surgical or catheter-based aortic valve replacement and were expected to have low physical activity-induced muscle atrophy. We obtained short-axis images of the mid-thigh using an ultrasonic diagnostic imaging system (with a 5-cm-wide probe) and measured the deviation of the central region of the rectus femoris from the body surface. Muscle thickness was measured using conventional morphological measurements on the body surface ("On Surface") and landmarks within the ultrasonographic image ("In Images").

RESULTS

Displacements ≥ 1.5 cm were observed in 56 (54.9%) limbs, and displacements ≥ 2.5 cm were observed in 34 (33%) limbs. The displacements were predominantly in the medial direction and ranged from 4 cm to 1.5 cm. Among the cases in which the deviation was ≥2.5 cm, "On Surface" measurements resulted in images in which the vastus lateralis overlapped with the rectus femoris. The thickness of the rectus femoris was significantly lower with "On Surface" measurements than with "In Images" measurements (right, p < 0.001; left, p = 0.007), with a maximum difference of 10.5 mm.

CONCLUSIONS

In conclusion, it was observed that the rectus femoris at the center was often displaced medially, and the muscle thickness was thinner at the edge than at the center, showing a non-uniform morphology.

Association of Regional Muscle Thickness and Echo Intensity with Muscle Volume, Intramuscular Adipose Tissue, and Strength of the Quadriceps Femoris

Purpose

This study aimed to investigate the association of muscle thickness (MT) and echo intensity (EI) obtained at different regions along the muscle length with muscle volume (MV), intramuscular adipose tissue (IntraMAT), and muscle strength of the quadriceps femoris (QF).

Patients and Methods

A total of 135 community-dwelling adults (64 men and 71 women) participated in the study. Ultrasound scanning of the rectus femoris (RF) and vastus intermedius (VI) was performed at three locations (from mid- to distal thigh). The MT of the RF and VI and EI of the RF were measured. MRI-derived MV, IntraMAT, and muscle strength of the QF were measured.

Results

The correlation between RF-MT and RF-MV weakened as scanning approached the distal thigh, and the difference between the coefficients for the scanning locations was significant for women. However, the correlation of VI-MT with VI-MV and that of the combined MT of RF and VI with the MV of the whole QF and muscle strength were comparable among the scanning locations for both sexes. The correlation of RF-EI with the IntraMAT of the RF and the whole QF and muscle strength was also comparable among the scanning locations for both sexes.

Conclusion

The results of this study suggest that ultrasound measurements at the distal thigh can predict MV, IntraMAT, and muscle strength of the QF to the same degree as those at the mid-thigh.

Sarcopenia, More Than Just Muscle Atrophy: Imaging Methods for the Assessment of Muscle Quantity and Quality

BACKGROUND

Sarcopenia, a progressive reduction of muscle mass and function, is associated with adverse outcomes in the elderly. Sarcopenia and muscle atrophy are not equal processes. Low muscle strength in association with muscle quantity/quality reduction is currently the optimal method for assessing sarcopenia. There is a practical need for indirect measurement of muscle strength using state-of-the-art imaging techniques.

METHODS

The following provides a narrative, broad review of all current imaging techniques for evaluating muscles and identifying sarcopenia, including DEXA, CT, MRI, and high-resolution ultrasound, their main strengths, weaknesses, and possible solutions to problems regarding each technique.

RESULTS AND CONCLUSION

Well-recognized imaging methods for the assessment of muscle mass are explained, including evaluation with DEXA, CT, and MRI muscle quantity assessment, ultrasound evaluation of muscle thickness and CSA, and their correlations with established muscle mass calculation methods. A special focus is on imaging methods for muscle quality evaluation. Several innovative and promising techniques that are still in the research phase but show potential in the assessment of different properties of muscle quality, including MRI DIXON sequences, MRI spectroscopy, Diffusion Tensor Imaging, ultrasound echo intensity, ultrasound elastography, and speed-of-sound ultrasound imaging are briefly mentioned.

KEY POINTS

· Sarcopenia definition includes low muscle strength and low muscle quantity/quality.. · DEXA is a low-radiation method for whole-body composition measurement in a single image.. · CT has established cut-off values for muscle quality/quantity evaluation and sarcopenia diagnosis.. · MRI is the most sophisticated muscle quality assessment method capable of evaluating myosteatosis, myofibrosis, and microstructure.. · Ultrasound can evaluate muscle quality, including tissue architecture, and elasticity with excellent spatial resolution..

CITATION FORMAT

· Vasilevska Nikodinovska V, Ivanoski S, . Sarcopenia, More Than Just Muscle Atrophy: Imaging Methods for the Assessment of Muscle Quantity and Quality. Fortschr Röntgenstr 2023; 195: 777 - 789.

Investigating the impact of fluid status on the ultrasound assessment of muscle quantity and quality in the diagnosis of sarcopenia - a multidimensional cross-sectional study

BACKGROUND

Sarcopenia is a clinical manifestation of adverse ageing, characterised by progressive loss of muscle mass and function. Diagnosis requires assessment of muscle quantity and quality; ultrasound represents an emerging tool for this. However, ultrasound muscle assessment may be impacted by fluid balance. This is particularly important when assessing for acute sarcopenia in hospitalised patients, where fluid disturbance often occurs. The primary aim of this study was to characterise the impact of fluid status on ultrasound muscle assessment, such that this may be accounted for in sarcopenia diagnostics.

METHODS

This Multidimensional Cross-sectional study involved 80 participants, who were inpatients at QEHB, a large UK tertiary centre. Fluid status was evaluated clinically and quantified using Bioelectrical Impedance Analysis (BIA). Muscle quantity was measured using Bilateral Anterior Thigh Thickness (BATT) with Rectus Femoris (RF) echogenicity used to assesses muscle adiposity and hence provide an inverse measure of muscle quality.

RESULTS

A significant positive correlation was found between fluid status, measured using BIA, and BATT as a measure of muscle quantity, in males (rs = 0.662, p < 0.001) and females (rs = 0.638, p < 0.001). A significant negative correlation was found between fluid status and RF echogenicity (rs=-0.448, p < 0.001).

CONCLUSIONS

These findings demonstrate associations between fluid balance and ultrasound assessment of muscle quantity and quality. Given the emerging use of ultrasound muscle assessment in sarcopenia diagnosis, there is a need to account for this in clinical practice. Future research should focus on the development of a corrective equation allowing assessment of muscle quantity and quality which account for changes in fluid status, hence aiding accurate diagnosis of sarcopenia.

Reliability of Muscle Quantity and Quality Measured With Extended-Field-of-View Ultrasound at Nine Body Sites

OBJECTIVE

Measuring muscle quantity and quality is very important because the loss of muscle quantity and quality is associated with several adverse effects specifically in older people. Ultrasound is a method widely used to measure muscle quantity and quality. One problem with ultrasound is its limited field of view, which makes it impossible to measure the muscle quantity and quality of certain muscles. In this study, we aimed to evaluate the intra- and inter-rater reliability of extended-field-of-view (EFOV) ultrasound for the measurement of muscle quantity and quality in nine muscles of the limbs and trunk.

METHODS

Two examiners took two ultrasound EFOV images with a linear probe from each of the muscle sites. The intraclass correlation coefficient (ICC) was used, and the standard error of measurement and coefficient of variation were calculated.

RESULTS

Intra-rater reliability was good to excellent (ICC = 0.2-1.00) for all muscle measurements. The inter-rater reliability for most of the muscle measurements was good to excellent (ICC = 0.82-0.98). Inter-rater reliability was moderate (0.58-0.72) for some muscle quantity measurements of the tibialis anterior, gastrocnemius, rectus femoris, biceps femoris and triceps brachii muscles.

CONCLUSION

Muscle quantity and quality can be measured reliably using EFOV US.

Ultrasound assessment of rectus femoris pennation angle and echogenicity. Their association with muscle functional measures and fat infiltration measured by CT scan

BACKGROUND & AIMS

Ultrasound can be used to measure the pennation angle between muscle fiver and the presumed axis of force generation and muscle echogenicity as an indicator of muscle fat infiltration. We aimed to assess the association of the rectus femoris pennation angle and echogenicity with muscle functional measures. Also, to assess the concordance of rectus femoris echogenicity with muscle fat infiltration as determined by CT scan.

METHODS

Rectus femoris ultrasound pennation angle and thickness were measured in 78 participants aged 69 (65,73) years (37 women). Also hand grip strength, gait speed in 4 m, the 12 min' walk and body composition by DEXA were measured. In a different group of 114 participants aged 44 (31,52) years (80 females), non-dominant rectus femoris echogenicity and thickness were measured by ultrasound and muscle fat infiltration was assessed by CT scan. Handgrip strength and quadriceps torque were also measured.

RESULTS

There was a weak correlation between the pennation angle and rectus femoris thickness in men (r = 0.31 p = 0.05) but not in women (r = 0.29 NS). Women, but not men with a low pennation angle covered a longer distance during the 12 min' walk. The concordance between the z scores of rectus femoris echogenicity and CT radiological density was 0.43 (p < 0.01) and 0.01 (NS) in men and women, respectively. Men and women with an echogenicity below the 25th percentile had a higher quadriceps torque. Men with an echogenicity 25th percentile below 25th percentile had also a higher handgrip strength.

CONCLUSIONS

Rectus femoris pennation angle had a weak or absent association with muscle performance. Rectus femoris echogenicity had a moderate overall concordance with radiological density by CT scan and was inversely associated with quadriceps torque. Therefore, echogenicity was associated with muscle strength, but pennation angle measurement did not contribute to the assessment of muscle function.

Sarcopenia and Cardiovascular Diseases

Sarcopenia is the loss of muscle strength, mass, and function, which is often exacerbated by chronic comorbidities including cardiovascular diseases, chronic kidney disease, and cancer. Sarcopenia is associated with faster progression of cardiovascular diseases and higher risk of mortality, falls, and reduced quality of life, particularly among older adults. Although the pathophysiologic mechanisms are complex, the broad underlying cause of sarcopenia includes an imbalance between anabolic and catabolic muscle homeostasis with or without neuronal degeneration. The intrinsic molecular mechanisms of aging, chronic illness, malnutrition, and immobility are associated with the development of sarcopenia. Screening and testing for sarcopenia may be particularly important among those with chronic disease states. Early recognition of sarcopenia is important because it can provide an opportunity for interventions to reverse or delay the progression of muscle disorder, which may ultimately impact cardiovascular outcomes. Relying on body mass index is not useful for screening because many patients will have sarcopenic obesity, a particularly important phenotype among older cardiac patients. In this review, we aimed to: (1) provide a definition of sarcopenia within the context of muscle wasting disorders; (2) summarize the associations between sarcopenia and different cardiovascular diseases; (3) highlight an approach for a diagnostic evaluation; (4) discuss management strategies for sarcopenia; and (5) outline key gaps in knowledge with implications for the future of the field.

FGF19 and muscle architecture in older patients

BACKGROUND

Sarcopenia has a significant medical and economic impact. Serum fibroblast growth factor 19 (FGF19) has recently been described as promoting muscle mass and strength, and could be an interesting marker for early diagnosis of sarcopenia and prevention of its consequences. Ultrasound is a robust non-invasive technique used to measure muscle parameters, which cannot be evaluated by usual body composition measures, but are known to be associated with muscle function. In this cross-sectional cohort study, we aimed to determine whether FGF19 levels were correlated with functional muscle tests and muscle ultrasound parameters.

METHODS

Patients over 70 years old with a mobility disability risk were recruited from the cohort of the "well on your feet" mobility loss prevention program. Sarcopenia was diagnosed according to the European Working Group on Sarcopenia in Older Patients 2 (EWGSOP2) criteria. We have performed functional battery tests, muscle ultrasound measures and bioimpedance spectroscopy. FGF19 levels were measured by the ELISA method.

RESULTS

Out of 52 patients involved (34 women, mean age 81.3 years), 30 patients were sarcopenic (15 patients with probable sarcopenia and 15 with certain sarcopenia). Sarcopenic patients were older (mean 82.8 versus 79.6 years, P = 0.033), with higher frailty Fried score (P = 0.006), lower IADL score (P = 0.008), had lower daily protein intakes (P = 0.023) and were less performant to muscle functional tests than non-sarcopenic patients. Serum FGF19 levels were negatively correlated with the SPPB score (r_s = 0.28; P = 0.045). FGF19 levels were correlated positively with the pennation angle (r_s = 0.31; P = 0.024), but negatively with muscle fiber length (r_s = -0.44; P = 0.001). We found no association between FGF19 and muscle thickness (P = 0.243).

CONCLUSION

We highlighted in older patients significant correlations between FGF19 levels, pennation angle and muscle fiber length, suggesting that FGF19 could provide an enabling environment for the development of large muscle fibers, as previously suggested in histological studies in mice. However, high FGF-19 levels were unexpectedly associated with a low SPPB score. Further studies are needed to validate and further elucidate these exploratory findings.

"SARCOPENIA MEASURED BY ULTRASOUND IN HOSPITALIZED OLDER ADULTS" (ECOSARC): multi-centre, prospective observational study protocol

BACKGROUND

Measurement of muscle mass and function, and thereafter, screening and diagnosis of sarcopenia, is a challenge and a need in hospitalized older adults. However, it is difficult in complex real-world old patients, because usually they are unable to collaborate with clinical, functional, and imaging testing. Ultrasound measurement of quadriceps rectus femoris (QRF) provides a non-invasive, real-time assessment of muscle quantity and quality, and is highly acceptable to participants with excellent inter-rater and intra-rater variability. However, normative data, protocol standardization, and association with longitudinal outcomes, needs further research and consensus.

METHODS

Prospective exploratory multicenter study in older adults admitted to Acute Geriatric Units (AGUs) for medical reasons. 157 subjects from 7 AGUs of Spain were recruited between May 2019 and January 2022. Muscle ultrasound measurements of the anterior vastus of the QRF were acquired on admission and on discharge, using a previously validated protocol, using a Chieson model ECO2 ultrasound system (Chieson Medical Technologies, Co. Ltd, Wimxu District Wuxi, Jiangsu, China). Measurements included the cross-sectional area, muscle thickness in longitudinal view, intramuscular central tendon thickness, echogenicity, and the presence or absence of edema and fasciculations. Functional, nutritional, and DXA measurements were provided. Clinical follow-up was completed at discharge, and 30 and 90 days after discharge. Variations between hospital admission and discharge ultrasound values, and the relationship with clinical variables, will be analyzed using paired t-tests, Wilcoxon tests, or Mc Nemar chi-square tests when necessary. Prevalence of sarcopenia will be calculated, as well as sensitivity and specificity of ultrasound measurements to determine sarcopenia. Kappa analysis will be used to analyze the concordance between measurements, and sensitivity analysis will be conducted for each participating center.

DISCUSSION

The results obtained will be of great interest to the scientific geriatric community to assess the utility and validity of ultrasound measurements for the detection and follow-up of sarcopenia in hospitalized older adults, and its association with adverse outcomes.

TRIAL REGISTRATION

NCT05113758. Registration date: November 9^th 2021. Retrospectively registered.

Intrinsic motor neuron excitability is increased after resistance training in older adults

This study investigated the effects of high-intensity resistance training on estimates of the motor neuron persistent inward current (PIC) in older adults. Seventeen participants (68.5 ± 2.8 yr) completed a 2-wk nonexercise control period followed by 6 wk of resistance training. Surface electromyographic signals were collected with two 32-channel electrodes placed over soleus to investigate motor unit discharge rates. Paired motor unit analysis was used to calculate delta frequency (ΔF) as an estimate of PIC amplitudes during 1) triangular-shaped contractions to 20% of maximum torque capacity and 2) trapezoidal- and triangular-shaped contractions to 20% and 40% of maximum torque capacity, respectively, to understand their ability to modulate PICs as contraction intensity increases. Maximal strength and functional capacity tests were also assessed. For the 20% triangular-shaped contractions, ΔF [0.58-0.87 peaks per second (pps); P ≤ 0.015] and peak discharge rates (0.78-0.99 pps; P ≤ 0.005) increased after training, indicating increased PIC amplitude. PIC modulation also improved after training. During the control period, mean ΔF differences between 20% trapezoidal-shaped and 40% triangular-shaped contractions were 0.09-0.18 pps (P = 0.448 and 0.109, respectively), which increased to 0.44 pps (P < 0.001) after training. Also, changes in ΔF showed moderate to very large correlations (r = 0.39-0.82) with changes in peak discharge rates and broad measures of motor function. Our findings indicate that increased motor neuron excitability is a potential mechanism underpinning training-induced improvements in motor neuron discharge rate, strength, and motor function in older adults. This increased excitability is likely mediated by enhanced PIC amplitudes, which are larger at higher contraction intensities.NEW & NOTEWORTHY Resistance training elicited important alterations in soleus intrinsic motor neuronal excitability, likely mediated by enhanced persistent inward current (PIC) amplitude, in older adults. Estimates of PICs increased after the training period, accompanied by an enhanced ability to increase PIC amplitudes at higher contraction intensities. Our data also suggest that changes in PIC contribution to self-sustained discharging may contribute to increases in motor neuron discharge rates, maximal strength, and functional capacity in older adults after resistance training.

Association of Sonographic Sarcopenia and Falls in Older Adults Presenting to the Emergency Department

BACKGROUND AND OBJECTIVE

To determine the association between point-of-care-ultrasonography (POCUS)-measured sarcopenia and grip strength, as well as the history of prior-year falls among older adults admitted to the emergency department observation unit (EDOU).

MATERIALS AND METHODS

This cross-sectional observational study was conducted over 8 months at a large urban teaching hospital. A consecutive sample of patients who were 65 years or older and admitted to the EDOU were enrolled in the study. Using standardized techniques, trained research assistants and co-investigators measured patients' biceps brachii and thigh quadriceps muscles via a linear transducer. Grip strength was measured using a Jamar Hydraulic Hand Dynamometer. Participants were surveyed regarding their history of falls in the prior year. Logistic regression analyses assessed the relationship of sarcopenia and grip strength to a history of falls (the primary outcome).

RESULTS

Among 199 participants (55% female), 46% reported falling in the prior year. The median biceps thickness was 2.22 cm with an Interquartile range [IQR] of 1.87-2.74, and the median thigh muscle thickness was 2.91 cm with an IQR of 2.40-3.49. A univariate logistic regression analysis demonstrated a correlation between higher thigh muscle thickness, normal grip strength, and history of prior-year falling, with an odds ratio [OR] of 0.67 (95% conference interval [95%CI] 0.47-0.95) and an OR of 0.51 (95%CI 0.29-0.91), respectively. In multivariate logistic regression, only higher thigh muscle thickness was correlated with a history of prior-year falls, with an OR of 0.59 (95% CI 0.38-0.91).

CONCLUSIONS

POCUS-measured thigh muscle thickness has the potential to identify patients who have fallen and thus are at high risk for future falls.

Reproducibility and feasibility of a handheld ultrasound device compared to a standard ultrasound machine in muscle thickness measurements

Objective

To test the feasibility and reproducibility of a handheld ultrasound device (HUD) compared to a standard ultrasound machine for muscle thickness measurements in healthy participants.

Methods

A prospective cross-sectional study was designed where two novice operators tested the thickness of the vastus lateralis, rectus femoris, and vastus intermedius muscles on recruited asymptomatic participants with no history of muscle diseases. The anterior-posterior thickness of each muscle was measured three times per operator to evaluate intra-operator reproducibility and using two machines to evaluate inter-system reproducibility. Scanning started using the HUD followed by the standard system. Intraclass correlation coefficients (ICC) and simple linear regression were used to test for reproducibility and proportional bias respectively.

Results

A total of 33 male participants volunteered to take part in this study with a mean age of 22.7 years (6.8). Intra-operator reproducibility was almost perfect for both operators on both machines (ICC > 0.80). The measurements difference percentage between the machines ranged from 1.8% to 6.6% and inter-system reproducibility ICC ranged from 0.815 to 0.927 showing excellent reproducibility. Inter-operator reproducibility was poor to moderate on both machines (ICC: 0.522-0.849). Regression analysis showed no proportional bias in the measurements. All measurements were completed successfully using the HUD.

Conclusion

The HUD demonstrated excellent accuracy compared to the standard ultrasound machine for measuring thigh muscle thickness.

Diagnostic test accuracy of ultrasound for sarcopenia diagnosis: A systematic review and meta-analysis

Muscle ultrasound is an emerging tool for diagnosing sarcopenia. This review aims to summarize the current knowledge on the diagnostic test accuracy of ultrasound for the diagnosis of sarcopenia. We collected data from Ovid Medline, Embase and the Cochrane Central Register of Controlled Trials. Diagnostic test accuracy studies using muscle ultrasound to detect sarcopenia were included. Bivariate random-effects models based on sensitivity and specificity pairs were used to calculate the pooled estimates of sensitivity, specificity and the area under the curves (AUCs) of summary receiver operating characteristic (SROC), if possible. We screened 7332 publications and included 17 studies with 2143 participants (mean age range: 52.6-82.8 years). All included studies had a high risk of bias. The study populations, reference standards and ultrasound measurement methods varied across the studies. Lower extremity muscles were commonly studied, whereas muscle thickness (MT) was the most widely measured parameter, followed by the cross-sectional area (CSA). The MTs of the gastrocnemius, rectus femoris, tibialis anterior, soleus, rectus abdominis and geniohyoid muscles showed a moderate diagnostic accuracy for sarcopenia (SROC-AUC 0.83, 8 studies; SROC-AUC 0.78, 5 studies; AUC 0.82, 1 study; AUC 0.76-0.78, 2 studies; AUC 0.76, 1 study; and AUC 0.79, 1 study, respectively), whereas the MTs of vastus intermedius, quadriceps femoris and transversus abdominis muscles showed a low diagnostic accuracy (AUC 0.67-0.71, 3 studies; SROC-AUC 0.64, 4 studies; and AUC 0.68, 1 study, respectively). The CSA of rectus femoris, biceps brachii muscles and gastrocnemius fascicle length also showed a moderate diagnostic accuracy (AUC 0.70-0.90, 3 studies; 0.81, 1 study; and 0.78-0.80, 1 study, respectively), whereas the echo intensity (EI) of rectus femoris, vastus intermedius, quadriceps femoris and biceps brachii muscles showed a low diagnostic accuracy (AUC 0.52-0.67, 2 studies; 0.48-0.50, 1 study; 0.43-0.49, 1 study; and 0.69, 1 study, respectively). The combination of CSA and EI of biceps brachii or rectus femoris muscles was better than either CSA or EI alone for diagnosing sarcopenia. Muscle ultrasound shows a low-to-moderate diagnostic test accuracy for sarcopenia diagnosis depending on different ultrasound parameters, measured muscles, reference standards and study populations. The combination of muscle quality indicators (e.g., EI) and muscle quantity indicators (e.g., MT) might provide better diagnostic test accuracy.

Reliability assessment of ultrasound muscle echogenicity in patients with rheumatic diseases: Results of a multicenter international web-based study

Objectives

To investigate the inter/intra-reliability of ultrasound (US) muscle echogenicity in patients with rheumatic diseases.

Methods

Forty-two rheumatologists and 2 radiologists from 13 countries were asked to assess US muscle echogenicity of quadriceps muscle in 80 static images and 20 clips from 64 patients with different rheumatic diseases and 8 healthy subjects. Two visual scales were evaluated, a visual semi-quantitative scale (0-3) and a continuous quantitative measurement ("VAS echogenicity," 0-100). The same assessment was repeated to calculate intra-observer reliability. US muscle echogenicity was also calculated by an independent research assistant using a software for the analysis of scientific images (ImageJ). Inter and intra reliabilities were assessed by means of prevalence-adjusted bias-adjusted Kappa (PABAK), intraclass correlation coefficient (ICC) and correlations through Kendall's Tau and Pearson's Rho coefficients.

Results

The semi-quantitative scale showed a moderate inter-reliability [PABAK = 0.58 (0.57-0.59)] and a substantial intra-reliability [PABAK = 0.71 (0.68-0.73)]. The lowest inter and intra-reliability results were obtained for the intermediate grades (i.e., grade 1 and 2) of the semi-quantitative scale. "VAS echogenicity" showed a high reliability both in the inter-observer [ICC = 0.80 (0.75-0.85)] and intra-observer [ICC = 0.88 (0.88-0.89)] evaluations. A substantial association was found between the participants assessment of the semi-quantitative scale and "VAS echogenicity" [ICC = 0.52 (0.50-0.54)]. The correlation between these two visual scales and ImageJ analysis was high (tau = 0.76 and rho = 0.89, respectively).

Conclusion

The results of this large, multicenter study highlighted the overall good inter and intra-reliability of the US assessment of muscle echogenicity in patients with different rheumatic diseases.

Differential association of total and regional muscle mass and quality with physical performance in community-dwelling older adults

PURPOSE

In this study, we examined the association among total muscle mass, regional muscle mass, muscle quality, and various types of physical performance in community-dwelling older adults.

METHODS

This study included 195 community-dwelling older adults (61 males and 134 females). The muscle thickness and echo intensity of the quadriceps femoris and triceps surae were measured using ultrasound, and the skeletal muscle mass index was evaluated using bioelectrical impedance analysis. Physical performance was measured using the 30-s standing test (CS30), Timed up-and-go test (TUG), 10-m maximum walking speed (10MWT), vertical jump test (VJT), and grip strength.

RESULTS

Partial correlation analysis after controlling for age, sex, and body mass index showed that CS30 was significantly correlated with muscle thickness and echo intensity of the quadriceps femoris. The TUG and VJT were significantly correlated with muscle thickness of the triceps surae, and grip strength was significantly correlated with muscle thickness of the triceps surae and skeletal muscle mass index. Stepwise multiple regression analyses indicated that the echo intensity of the quadriceps femoris was a significant predictor of CS30, and the muscle thickness of the triceps surae was a significant predictor of TUG, VJT, and grip strength, whereas the skeletal muscle mass index was not a significant predictor of any physical performance test.

CONCLUSION

Our results suggest that regional muscle mass and quality are more important than skeletal muscle mass index for predicting physical performance.

Ultrasonographic findings in long COVID: A cross-sectional study of 312 patients

Background

Fatigue and muscle weakness are common complaints in COVID-19 survivors. However, little is still known about the skeletal muscle qualitative and quantitative characteristics after hospitalization due to moderate and severe COVID-19.

Objectives

To assess rectus femoris and vastus intermedius muscle thickness (MT) and rectus femoris echo intensity (EI) and to establish its association with demographic, clinical, functional, and inflammatory parameters in long COVID patients after hospital discharge.

Methods

Cross-sectional study with 312 COVID-19 patients (53.53% male; age: 54.59 ± 13.50 years), with a laboratory-confirmed diagnosis of COVID-19. Patients were assessed 3-11 months after hospital discharge. We evaluated MT of the right rectus femoris and vastus intermedius and EI of the right rectus femoris using a portable ultrasound system, 6-13 MHz, broadband linear transducer. We corrected EI using the subcutaneous fat thickness. Ultrasonographic parameters were tested in association with demographic (sex and age); functional (Handgrip strength measurement, Timed Up and Go, 1 min Sit-to-Stand test, EuroQoL-5 Dimensions-5 Levels, World Health Organization Disability Assessment Schedule (WHODAS 2.0), Post-COVID-19 Functional Status, Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT), Medical Research Council (MRC) sum score, Borg Dyspnea Scale, MRC Dyspnea score, Visual Analogue Scale (VAS), Epworth Sleepiness Scale, Insomnia Severity Index, Functional Independence Measurement (FIM), and Functional Oral Intake Scale); clinical (length of hospital stay, intubation, and presence of comorbidities such as systemic hypertension, diabetes, obesity, chronic obstructive pulmonary disease, asthma), and inflammatory data assessed by the C-reactive protein and D-dimer serum concentrations.

Results

Rectus femoris MT was associated with age, handgrip strength, Epworth Sleepiness Scale, and subcutaneous fat thickness (r² = 27.51%; p < 0.0001). Vastus intermedius MT was associated with age, pain intensity, handgrip strength, Epworth Sleepiness scale, FIM, and time since hospital discharge (r² = 21.12%; p < 0.0001). Rectus femoris EI was significantly associated with the male sex, TUG, Epworth Sleepiness Scale, and C-Reactive Protein levels (r² = 44.39%; p < 0.0001). Mean MT of rectus femoris and vastus intermedius are significantly different (p < 0.001).

Conclusion

After hospital discharge, long COVID patients present qualitative and quantitative skeletal muscle characteristics associated with a combination of demographic, clinical, and functional parameters.

Ultrasound-derived muscle assessment system for older adults: a promising muscle mass estimation tool

BACKGROUND

Quantitative assessment of muscle mass is a critical step in sarcopenia disease management. Expanding upon the use of ultrasound in foetal growth assessment, we established and validated an ultrasound-derived muscle assessment system for older adults at a risk of sarcopenia.

METHODS

A total of 669 older adults were recruited in three cohorts in this cross-sectional study. In cohort 1(n = 103), the most valuable sites for skeletal muscle mass index (SMI) estimation were located among 11 ultrasound scanning sites. An ultrasound-derived SMI estimating algorithm based on muscle thickness (MT) was obtained in the modelling group composed of cohorts 1 and 2 (n = 309). The reliability of the muscle mass estimation equation and the validity of the obtained cut-off values were verified in cohort 3 (n = 257), which was selected as the verification group.

RESULTS

In the modelling group, the cut-off values of ultrasound-derived e-SMI for low SMI were 7.13 kg/m2 for men and 5.81 kg/m2 for women. In the verification group, the intraclass correlation between e-SMI and SMI was 0.885. The sensitivity of the e-SMI in detecting low SMI was 93.6% for men and 89.7% for women, and the negative predictive value was 94.9% for men and 94.7% for women. Combined with the handgrip strength and gait speed, the e-SMI had an overall diagnostic sensitivity of 92.7% and a specificity of 91.0% for sarcopenia.

CONCLUSION

The ultrasound-derived muscle assessment system can be a promising muscle mass estimation tool and a potential disease classification tool.

Relationship between quadriceps femoris muscle architecture and muscle strength and physical function in older adults with heart failure with preserved ejection fraction

Heart failure (HF)-related factors potentially lead to sarcopenia. Ultrasound (US) assessment has all the advantages of being used in clinical practice to assess muscle architecture. This study aimed to assess the relationship between the quadriceps femoris (QF) muscle architecture with the gender, age, body mass index (BMI), muscle strength and physical function in older adults with HF with preserved ejection fraction (HFpEF) as well as to assess the difference in these relationships between the two genders. Patients 70 years and older with HFpEF were included. The gender, age and BMI were collected. The QF muscle thickness, the QF muscle echo-intensity, the subcutaneous fat tissue thickness (FT) and the subcutaneous fat tissue echo-intensity were assessed by the US. The six-minute walk test, the short physical performance battery (SPPB), the timed up and go test (TUG), and the gait speed test (UGS) were used to assess physical function. The five-repetitions sit-to-stand test (5-STS) was performed to assess muscle strength. Bivariant Pearson correlations and subsequent multivariate linear regression analysis were conducted. Seventy older adults with HFpEF [81.00 (5.97) years] were recruited. The FT showed a correlation between poor and moderate muscle strength and physical function in women with HFpEF. The FT explained 24.5% of the 5-STS variance, 32.4% of the SPPB variance, 31.5% of the TUG variance, 28.6% of the UGS variance, and 21.4% of the FGS variance in women. The US assessment could allow clinicians to assess muscle architecture biomarkers related to muscle strength and physical function in older adults with HFpEF.Trial registration NCT03909919. April 10, 2019. Retrospectively registered.

Skeletal Muscle Complications in Chronic Kidney Disease

PURPOSE OF REVIEW

To provide an overview of the recent literature investigating the pathophysiology of skeletal muscle changes, interventions for skeletal muscle, and effects of exercise in chronic kidney disease (CKD).

RECENT FINDINGS

There are multiple CKD-related changes that negatively impact muscle size and function. However, the variability in the assessment of muscle size, in particular, hinders the ability to truly understand the impact it may have in CKD. Exercise interventions to improve muscle size and function demonstrate inconsistent responses that warrant further investigation to optimize exercise prescription. Despite progress in the field, there are many gaps in the knowledge of the pathophysiology of sarcopenia of CKD. Identifying these gaps will help in the design of interventions that can be tested to target muscle loss and its consequences such as impaired mobility, falls, and poor quality of life in patients with CKD.

Musculoskeletal Ultrasound Shows Muscle Mass Changes during Post-Acute Care Hospitalization in Older Men: A Prospective Cohort Study

This study aimed to prospectively assess changes in muscle thickness (MT) and the cross-sectional area (CSA) of the rectus femoris (RF) muscle in a cohort of older adults, using musculoskeletal ultrasound at admission and at a 2-week follow-up during hospitalization in a post-acute care unit. Differences in frailty status and correlations of MT-RF and CSA-RF with current sarcopenia diagnostic criteria were also studied. Forty adults aged 79.5 (SD 9.5) years (57.5% women) participated, including 14 with frailty and 26 with pre-frailty. In the first week follow-up, men had a significant increase in MT (0.9 mm [95%CI 0.3 to 1.4], p = 0.003) and CSA (0.4 cm² [95%CI 0.1 to 0.6], p = 0.007). During the second week, men continued to have a significant increase in MT (0.7 mm [95%CI 0.0 to 1.4], p = 0.036) and CSA (0.6 cm² [95%CI 0.01 to 1.2], p = 0.048). Patients with frailty had lower values of MT-RF and CSA-RF at admission and during the hospitalization period. A moderate-to-good correlation of MT-RF and CSA with handgrip strength, fat-free mass and gait speed was observed. Musculoskeletal ultrasound was able to detect MT-RF and CSA-RF changes in older adults admitted to a post-acute care unit.

Clinical evaluation of automated segmentation for body composition analysis on abdominal L3 CT slices in polytrauma patients

INTRODUCTION

Sarcopenia is a muscle disease that involves loss of muscle strength and physical function and is associated with adverse health effects. Even though sarcopenia has attracted increasing attention in the literature, many research findings have not yet been translated into clinical practice. In this article, we aim to validate a deep learning neural network for automated segmentation of L3 CT slices and aim to explore the potential for clinical utilization of such a tool for clinical practice.

MATERIALS AND METHODS

A deep learning neural network was trained on a multi-centre collection of 3413 abdominal cancer surgery subjects to automatically segment muscle, subcutaneous and visceral adipose tissue at the L3 lumbar vertebral level. 536 Polytrauma subjects were used as an independent test set to show generalizability. The Dice Similarity Coefficient was calculated to validate the geometric similarity. Quantitative agreement was quantified using Bland-Altman's Limits of Agreement interval and Lin's Concordance Correlation Coefficient. To determine the potential clinical usability, randomly selected segmentation images were presented to a panel of experienced clinicians to rate on a Likert scale.

RESULTS

Deep learning results gave excellent agreement versus a human expert operator for all of the body composition indices, with Concordance Correlation Coefficient for skeletal muscle index of 0.92, Skeletal muscle radiation attenuation 0.94, Visceral Adipose Tissue index 0.99 and Subcutaneous Adipose Tissue Index 0.99. Triple-blinded visual assessment of segmentation by clinicians correlated only to the Dice coefficient, but had no association to quantitative body composition metrics which were accurate irrespective of clinicians' visual rating.

CONCLUSION

A deep learning method for automatic segmentation of truncal muscle, visceral and subcutaneous adipose tissue on individual L3 CT slices has been independently validated against expert human-generated results for an enlarged polytrauma registry dataset. Time efficiency, consistency and high accuracy relative to human experts suggest that quantitative body composition analysis with deep learning should is a promising tool for clinical application in a hospital setting.

The Diagnostic Value of Ultrasound of the Rectus Femoris for the diagnosis of Sarcopenia in adults: A systematic review

BACKGROUND & AIM

Sarcopenia is defined as a loss of muscle mass and function, which can be caused by normal ageing or factors such as physical inactivity. Severe health consequences caused by sarcopenia highlight the need for early identification. Computed Tomography (CT) imaging, often mentioned as the gold standard due to its accuracy, is costly and not routinely performed in daily clinical care. Ultrasound of the rectus femoris, however, is low in costs and easily accessible. The aim is to present the current and most recent literature regarding the diagnostic value of ultrasound measurements of the rectus femoris for the diagnosis of sarcopenia in adults.

METHODS

The databases PubMed and Web of Science were used to search for studies comparing ultrasound of the rectus femoris with a reference test to diagnose sarcopenia in adults. The quality of the final eligible studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies, version 2, tool (QUADAS-2).

RESULTS

Six studies were included in this systematic review. The muscle thickness and cross-sectional area of the rectus femoris were assessed and compared with the reference tests CT, Dual-Energy X-ray Absorptiometry (DXA), and Bioelectrical Impedance Analysis (BIA). Half of the studies had a low risk of bias on all QUADAS-2 domains. Three studies reported statistical significant outcomes and diagnostic values ranging from 60 to 81% sensitivity and 51 to 94% specificity.

CONCLUSIONS

Ultrasound of the rectus femoris muscle to diagnose sarcopenia has been shown to be a promising method in multiple clinical populations. However, there were some limitations such as a high methodological heterogeneity. Future research should develop standardized protocols and determine clear cut-off values to allow for a better implementation of ultrasound in clinical practice.

Diagnostic Utility of Temporal Muscle Thickness as a Monitoring Tool for Muscle Wasting in Neurocritical Care

Temporalis muscle (TM) atrophy has emerged as a potential biomarker for muscle wasting. However, its diagnostic utility as a monitoring tool in intensive care remains uncertain. Hence, the objective of this study was to evaluate the diagnostic value of sequential ultrasound- and computed tomography (CT)-based measurements of TM thickness (TMT). With a prospective observational design, we included 40 patients without preexisting sarcopenia admitted to a neurointensive care unit. TMT measurements, performed upon admission and serially every 3−4 days, were correlated with rectus femoris muscle thickness (RFT) ultrasound measurements. Interrater reliability was assessed by Bland Altmann plots and intraclass correlation coefficient (ICC). Analysis of variance was performed in subgroups to evaluate differences in the standard error of measurement (SEM). RFT decline was paralleled by ultrasound- as well as CT-based TMT measurements (TMT to RFT: r = 0.746, p < 0.001; CT-based TMT to ultrasound-based RFT: r = 0.609, p < 0.001). ICC was 0.80 [95% CI 0.74, 0.84] for ultrasound-based assessment and 0.90 [95% CI 0.88, 0.92] for CT-based TMT measurements. Analysis of variance for BMI, Heckmatt score, fluid balance, and agitation showed no evidence of measurement errors in these subgroups. This study demonstrates the clinical feasibility and utility of ultrasound- and CT-based TMT measurements for the assessment of muscle wasting.

Biomarkers and the quadriceps femoris muscle architecture assessed by ultrasound in older adults with heart failure with preserved ejection fraction: a cross-sectional study

BACKGROUND

Sarcopenia is an important comorbidity in patients with heart failure with preserved ejection fraction (HFpEF). The ultrasound (US) assessment has all the advantages of being used in primary care to assess muscle quantity and quality. Some biomarkers could be indicative of muscle mass loss.

AIMS

To describe the quantitative and qualitative characteristics of the quadriceps femoris assessed by US in older adults with HFpEF and to assess the relationship of the blood and urinary biomarkers, the polypharmacy and comorbidities with US outcomes in older adults with HFpEF.

METHODS

A cross-sectional study was conducted. 76 older adults with HFpEF were included. The quadriceps femoris muscle thickness (MT, cm), the subcutaneous fat tissue thickness (FT, cm), the muscle echo intensity (MEI) and the subcutaneous fat tissue echo intensity (FEI) were assessed by US in a non-contraction (non-con) and contraction (con) situations. Polypharmacy, comorbidities, blood and urine biomarkers were also collected.

RESULTS

The carbohydrate antigen 125 (CA-125), the folic acid and the urine creatinine shared the 86.6% variance in the non-con MT, adjusted by age, sex and body mass index (BMI). The folic acid shared the 38.5% of the variance in the con MT, adjusted by age, sex and BMI. The glycosylated haemoglobin explained the 39.6% variance in the non-con MEI, adjusted by age, sex and BMI. The chlorine (Cl-) explained the 40.2% of the variance in the non-con FT, adjusted by age, sex and BMI. The polypharmacy and the folic acid explained the 37.9% of variance in the non-con FEI, while the polypharmacy and the thyrotropin (TSH) shared the 44.4% of variance in the con FEI, both adjusted by age, sex and BMI. No comorbidities, polypharmacy, or blood and urinary biomarkers could explain the con MEI and the con FT variance.

CONCLUSIONS

Blood and urinary biomarkers obtained in routine analyses could help clinicians detect US outcome changes in older adults with HFpEF and identify a worsening of sarcopenia.

TRIAL REGISTRATION

NCT03909919. April 10, 2019. Retrospectively registered.

Ultrasonography for Assessment of Sarcopenia: A Primer

The human skeletal muscle has a pivotal role in preserving health by maintaining mobility, balance, and metabolic homeostasis. Significant muscle loss as a part of aging and accelerated by disease leads to sarcopenia which becomes an important predictor of quality of life in older persons. Therefore, clinical screening for sarcopenia and validation by precise qualitative and quantitative measurement of skeletal muscle mass (MM) and function is at the center-stage of translational research. Many imaging modalities are available, each having their strengths and limitations, either in interpretation, technical processes, time constraints, or expense. B-mode ultrasonography (US) is a relatively novel approach to evaluating muscle. It can measure several parameters such as MM and architecture simultaneously including muscle thickness, cross-sectional area, echogenicity, pennate angle, and fascicle length. It can also evaluate dynamic parameters like muscle contraction force and muscle microcirculation. US has not gained global attention due to a lack of consensus on standardization and diagnostic threshold values to diagnose sarcopenia. However, it is an inexpensive and widely available technique with clinical applicability. The ultrasound-derived parameters correlate well with strength and functional capacity and provide potential prognostic information. Our aim is to present an update on the evidence-based role of this promising technique in sarcopenia, its advantages over the existing modalities, and its limitations in actual practice with the hope that it may emerge as the "stethoscope" for community diagnosis of sarcopenia.

Biceps femoris long head morphology in youth competitive alpine skiers is associated with age, biological maturation and traumatic lower extremity injuries

Lower extremity injuries are common in competitive alpine skiers, and the knee and lower leg are often affected. The hamstring muscles, especially the biceps femoris long head (BFlh), can stabilize the knee and the hip and may counteract various adverse loading patterns during typical mechanisms leading to severe lower extremity injuries. The aim of the present study was to describe BFlh morphology in youth competitive alpine skiers in relation to sex, age and biological maturation and to investigate its association with the occurrence of traumatic lower extremity injuries in the upcoming season. 95 youth skiers underwent anthropometric measurements, maturity offset estimations and ultrasound assessment, followed by 12-months prospective injury surveillance. Unpaired t tests showed that the two sexes did not differ in BFlh morphology, including fascicle length (Lf), pennation angle (PA), muscle thickness (MT) and average anatomical cross-sectional area (ACSA_avg). In contrast, U16 skiers had longer fascicles than U15 skiers (9.5 ± 1.3 cm vs 8.9 ± 1.3 cm, p < 0.05). Linear regression analyses revealed that maturity offset was associated with Lf (R² = 0.129, p < 0.001), MT (R² = 0.244, p < 0.001) and ACSA_avg (R² = 0.065, p = 0.007). No association was found between maturity offset and PA (p = 0.524). According to a binary logistic regression analysis, ACSA_avg was significantly associated with the occurrence of traumatic lower extremity injuries (Chi-square = 4.627, p = 0.031, R_Nagelkerke² = 0.064, Cohen f = 0.07). The present study showed that BFlh morphology is age- and biological maturation-dependent and that BFlh ACSA_avg can be considered a relevant modifiable variable associated with lower extremity injuries in youth competitive alpine skiers.

Architectural Ultrasound Pennation Angle Measurement of Lumbar Multifidus Muscles: A Reliability Study

The pennation angle has been shown to be a relevant parameter of muscle architecture. This parameter has not previously been measured in the lumbar multifidus musculature, and it is for this reason that it has been considered of great interest to establish an assessment protocol to generate new lines of research in the future. Objective: The objective of this study was to establish a protocol for measuring the pennation angle of the multifidus muscles, with a study of intra-rater and interrater reliability values. Design: This was a reliability study following the recommendations of the Guidelines for Reporting Reliability and Agreement Studies (GRRAS). Setting: The study was carried out at University of Alcalá, Department of Physiotherapy. Subjects: Twenty-seven subjects aged between 18 and 55 years were recruited for this study. Methods: Different ultrasound images of the lumbar multifidus musculature were captured. Subsequently, with the help of ImageJ software, the pennation angle of this musculature was measured. Finally, a complex statistical analysis determined the intra- and interrater reliability. Results: The intra-rater reliability of the pennation angle measurement protocol was excellent for observer 1 in the measurement of the left-sided superficial multifidus 0.851 (0.74, 0.923), and for observer 2 in the measurement of the right-sided superficial 0.711 (0.535, 0.843) and deep multifidus 0.886 (0.798, 0.942). Interrater reliability was moderate to poor, and correlation analysis results were high for thickness vs. pennation angle. Conclusions: The designed protocol for ultrasound measurement of the pennation angle of the lumbar multifidus musculature has excellent intra-rater reliability values, supporting the main conclusions and interpretations. Normative ranges of pennation angles are reported. High correlation between variables is described.

Ultrasound Assessment of Changes in Muscle Architecture of the Brachialis Muscle After Stroke—A Prospective Study

Objective

To investigate changes in ultrasound-derived muscle architecture parameters of the brachialis and correlations in patients with subacute stroke.

Design

Prospective longitudinal observational study.

Setting

Tertiary inpatient rehabilitation center.

Participants

Fifty adult patients (N=50) who were recruited within the first month poststroke. The patients had a mean age of 57.2±12.3 years and 68.0% were male. The majority of patients had significant upper limb weakness with a low mean Motricity Index of 18.5±24.7 and median elbow flexor strength of grade 0.

Intervention

Not applicable.

Main Outcome Measures

Ultrasound of the intact and hemiparetic brachialis was performed at 3-time intervals: within 1 month of stroke onset and at 1 and 6 months after first assessment. Clinical variables captured included upper limb motor power and elbow flexor spasticity.

Results

Compared to the intact brachialis, there was reduced muscle thickness (1.93 cm vs 2.07 cm, 1.86 cm vs 2.08 cm, 1.85 cm vs 2.05 cm; P=.022) and increased echo intensity (63.3 arbitrary units [AU] vs 56.8 AU, 69.4 AU vs 56.6 AU, 77.4 AU vs 58.2 AU; P<.001) in the hemiparetic brachialis at all assessment intervals (baseline, 1 month, 6 months). Reduction in muscle mass was greater in older patients, with the correlation coefficient ranging from −0.30 (P=.03) at baseline to −0.50 (P<.001) at 6 months. Presence of elbow flexor spasticity at 1-month assessment interval was associated with lower muscle mass reduction (1.93 cm vs 1.74 cm; P=.017), lower echo intensity (65.1 AU vs 75.1 AU; P=.023), and longer fascicle lengths (12.92 cm vs 9.83 cm; P=.002).

Conclusions

Changes including decreased muscle thickness and increased echo intensity of the hemiparetic brachialis were noted over time. Elbow flexor spasticity at 1-month assessment interval appears to mitigate against these changes.

Muscle Ultrasound as Imaging Domain of Frailty

Introduction

Frailty is a geriatric syndrome, a clinical state of vulnerability for developing dependency and/or death. Due to its multidimensional nature, Comprehensive Geriatric Assessment (CGA) constitutes the best strategy to evaluate frailty in older patients. Accumulation of deficits model synthesizes the global assessment of geriatric domains in the Frailty Index (FI) score. Muscle Ultrasound (MUS) has been employed to evaluate muscle mass wasting as tool to assess sarcopenia in late life. The present study aims to evaluate the association between CGA-based FI and MUS measures in a population of hospitalized older adults.

Methods

Patients aged ≥65 years underwent CGA for the evaluation of the domains of health and functional status, psycho-cognition, nutritional status, socio-environmental condition. Following standard procedure, a CGA-based FI was elaborated, taking into account 38 multidimensional items. Muscle thicknesses (MT) of rectus femoris plus vastus intermedius were measured through MUS axial cross-section. Multivariable regression analysis was employed to determine factors associated with FI.

Results

The study population consisted of 136 older patients, 87 men (63.9%), with median age of 74 (70–81) years, FI of 0.3 (0.21–0.46), and MT of rectus femoris plus vastus intermedius 29.27 (23.08–35.7) mm. At multivariable regression analysis, FI resulted significantly and independently associated with age and MT.

Conclusion

Muscle thicknesses of rectus femoris plus vastus intermedius, measured through MUS, resulted to be significantly related to FI in a population of hospitalized older patients. In the CGA-based assessment of frailty, MUS may constitute an additional imaging domain.

Measurement of Sarcopenia in Head and Neck Cancer Patients and Its Association With Frailty

In head and neck cancer (HNC) there is a need for more personalized treatment based on risk assessment for treatment related adverse events (i.e. toxicities and complications), expected survival and quality of life. Sarcopenia, defined as a condition characterized by loss of skeletal muscle mass and function, can predict adverse outcomes in HNC patients. A review of the literature on the measurement of sarcopenia in head and neck cancer patients and its association with frailty was performed. Skeletal muscle mass (SMM) measurement only is often used to determine if sarcopenia is present or not. SMM is most often assessed by measuring skeletal muscle cross-sectional area on CT or MRI at the level of the third lumbar vertebra. As abdominal scans are not always available in HNC patients, measurement of SMM at the third cervical vertebra has been developed and is frequently used. Frailty is often defined as an age-related cumulative decline across multiple physiologic systems, with impaired homeostatic reserve and a reduced capacity of the organism to withstand stress, leading to increased risk of adverse health outcomes. There is no international standard measure of frailty and there are multiple measures of frailty. Both sarcopenia and frailty can predict adverse outcomes and can be used to identify vulnerable patients, select treatment options, adjust treatments, improve patient counselling, improve preoperative nutritional status and anticipate early on complications, length of hospital stay and discharge. Depending on the definitions used for sarcopenia and frailty, there is more or less overlap between both conditions. However, it has yet to be determined if sarcopenia and frailty can be used interchangeably or that they have additional value and should be used in combination to optimize individualized treatment in HNC patients.

Ultrasound Assessment of Sarcopenia in Patients With Sarcoidosis

OBJECTIVES

Sarcoidosis can cause sarcopenia like other chronic diseases. Ultrasonography is a simple method, which has been used frequently in recent years. We aimed to evaluate the sarcoidosis patients with ultrasonography for sarcopenia and to compare the results of ultrasonography with the accepted standard method, bioelectrical impedance analysis (BIA).

METHODS

BIA and handgrip test were applied to all patients diagnosed with sarcoidosis. The patients were classified according to the presence of probable sarcopenia with their handgrip results and the presence of sarcopenia with the appendicular skeletal muscle mass index calculated with using BIA. Ultrasonography was applied to each patient and the thickness of seven different muscle groups of the patients were evaluated. The ability of muscle thickness values measured by ultrasonography to predict sarcopenia was compared with the reference standard test BIA.

RESULTS

Forty patients (women/men = 31/9) were included in our study. The mean age was 53.2 ± 12.5 years. A statistically significant positive correlation was observed between handgrip strength and gastrocnemius medialis (GM), rectus femoris (RF) cross-sectional area, rectus abdominis (RA), external oblique (EO), transversus abdominus (TA), and diaphragm thicknesses. Therefore, there was a significant correlation between fat free mass index with RA, EO, and TA muscles. According to the ROC analysis, statistically significant muscle groups predicting sarcopenia were found as GM, RF cross-sectional area, EO, and IO. Again, according to the ROC analysis, it was seen that the thicknesses of GM, RA, EO, IO, and TA muscles corrected for BMI predicted probable sarcopenia with quite high sensitivity and specificity.

CONCLUSIONS

Muscle thicknesses measured by ultrasonography are helpful for the diagnosis of sarcopenia that may develop in chronic diseases such as sarcoidosis. Further studies with higher number of patients are needed to validate the results of the present pilot study.

Human skeletal muscle size with ultrasound imaging: a comprehensive review

Skeletal muscle size is an important factor in assessing adaptation to exercise training and detraining, athletic performance, age-associated atrophy and mobility decline, clinical conditions associated with cachexia, and overall skeletal muscle health. Magnetic resonance (MR) imaging and computed tomography (CT) are widely accepted as the gold standard methods for skeletal muscle size quantification. However, it is not always feasible to use these methods (e.g., field studies, bedside studies, large cohort studies). Ultrasound has been available for skeletal muscle examination for more than 50 years and the development, utility, and validity of ultrasound imaging are underappreciated. It is now possible to use ultrasound in situations where MR and CT imaging are not suitable. This review provides a comprehensive summary of ultrasound imaging and human skeletal muscle size assessment. Since the first study in 1968, more than 600 articles have used ultrasound to examine the cross-sectional area and/or volume of 107 different skeletal muscles in more than 27,500 subjects of various ages, health status, and fitness conditions. Data from these studies, supported by decades of technological developments, collectively show that ultrasonography is a valid tool for skeletal muscle size quantification. Considering the wide-ranging connections between human health and function and skeletal muscle mass, the utility of ultrasound imaging will allow it to be employed in research investigations and clinical practice in ways not previously appreciated or considered.