The importance of psoas muscle on low back pain: a single-center study on lumbar spine MRI.

Background: Low back pain (LBP) is the most frequent indication to magnetic resonance imaging (MRI) examinations of the lumbosacral spine. The individual role of soft tissues, including muscles, on LBP is not fully understood and the contribution of each MRI-derived parameter of soft tissues status on the intensity of LBP has not been investigated in detail. Methods: The study design was observational retrospective, single center carried out at a University Hospital. Images were acquired using a using a 1.5 Tesla scanner. Patients completed a symptom questionnaire and rated their pain intensity using the Visual Analogue Scale (VAS). The VAS scores ​​were categorized as mild, moderate, and severe using cutoff values of 3.8 and 5.7, based on the literature. Biometric data, including weight and height, were also recorded to calculate the body mass index (BMI). The ratios between intramuscular fat infiltration and net muscle area were also calculated. Patient sample included 94 patients with LBP underwent MRI of the lumbosacral spine. Results: The stepwise analysis revealed that increasing psoas net area was associated with lower VAS levels (odds ratio [OR]: 0.94: 95% confidence interval [CI]: 0.90-0.98; p=.005), and an increase of one square centimeter of total psoas area resulted in a greater probability of reporting a mild (+1.21%; 95% CI: 0.37, 2.05%) or a moderate VAS (+0.40%; 95% CI: -0.02, 0.82%), Furthermore, a more severe VAS was associated with a higher BMI (OR: 1.13; 95% CI: 1.00-1.27). Conclusion: Our study demonstrates a relationship between LBP and MRI parameters of paravertebral and psoas muscles status. The psoas muscle is extremely important for spine stabilization and is linked to clinical symptoms of patients affected by LBP. These findings could contribute to future studies and improve treatment options in patients with LBP, possibly reducing the impact on disability, quality of life and socioeconomical burden.

Relationship between paraspinal muscle properties and bone mineral density based on QCT in patients with lumbar disc herniation.

OBJECTIVE: Increasing research suggests that paraspinal muscle fat infiltration may be a potential biological marker for the assessment of osteoporosis. Our aim was to investigate the relationship between lumbar paraspinal muscle properties on MRI and volumetric bone mineral density (vBMD) based on QCT in patients with lumbar disc herniation (LDH). METHODS: A total of 383 patients (aged 24-76 years, 193 females) with clinically and radiologically diagnosed LDH were enrolled in this retrospective study. The muscle cross-sectional area (CSA) and the proton density fat fraction (PDFF) were measured for the multifidus (MF), erector spinae (ES) and psoas major (PS) at the central level of L3/4, L4/5 and L5/S1 on lumbar MRI. QCT was used to measure the vBMD of two vertebral bodies at L1 and L2 levels. Patients were divided into three groups based on their vBMD values: normal bone density group (> 120 mg/cm3), osteopenia group (80 to 120 mg/cm3) and osteoporosis group (< 80 mg/cm3). The differences in paraspinal muscle properties among three vBMD groups were tested by one-way ANOVA with post hoc analysis. The relationships between paraspinal muscle properties and vBMD were analyzed using Pearson correlation coefficients. Furthermore, the association between vBMD and paraspinal muscle properties was further evaluated using multiple linear regression analysis, with age and sex also included as predictors. RESULTS: Among the 383 LDH patients, 191 had normal bone density, 129 had osteopenia and 63 had osteoporosis. In LDH patients, compared to normal and osteopenia group, paraspinal muscle PDFF was significantly greater in osteoporosis group, while paraspinal muscle CSA was lower (p < 0.001). After adjusting for age and sex, it was found that MF PDFF and PS CSA were found to be independent factors influencing vBMD (p < 0.05). CONCLUSION: In patients with LDH, paraspinal muscle properties measured by IDEAL-IQ sequence and lumbar MR scan were found to be related to vBMD. There was a correlation between the degree of paraspinal muscle PDFF and decreasing vBMD, as well as a decrease paraspinal muscle CSA with decreasing vBMD. These findings suggest that clinical management should consider offering tailored treatment options for patients with LDH based on these associations.

Peripheral quantitative computed tomography is a valid imaging technique for tracking changes in skeletal muscle cross-sectional area.

Peripheral quantitative computed tomography (pQCT) has recently expanded to quantifying skeletal muscle, however its validity to determine muscle cross-sectional area (mCSA) compared to magnetic resonance imaging (MRI) is unknown. Eleven male participants (age: 22 ± 3 y) underwent pQCT and MRI dual-leg mid-thigh imaging before (PRE) and after (POST) 6 weeks of resistance training for quantification of mid-thigh mCSA and change in mCSA. mCSA agreement at both time points and absolute change in mCSA across time was assessed using Bland-Altman plots for mean bias and 95% limits of agreement (LOA), as well as Lin's concordance correlation coefficients (CCC). Both pQCT and MRI mCSA increased following 6 weeks of resistance training (∆mCSApQCT: 6.7 ± 5.4 cm2, p < 0.001; ∆mCSAMRI: 6.0 ± 6.4 cm2, p < 0.001). Importantly, the change in mCSA was not different between methods (p = 0.39). Bland-Altman analysis revealed a small mean bias (1.10 cm2, LOA: -6.09, 8.29 cm2) where pQCT tended to overestimate mCSA relative to MRI when comparing images at a single time point. Concordance between pQCT and MRI mCSA at PRE and POST was excellent yielding a CCC of 0.982. For detecting changes in mCSA, Bland-Altman analysis revealed excellent agreement between pQCT and MRI (mean bias: -0.73 cm2, LOA: -8.37, 6.91 cm2). Finally, there was excellent concordance between pQCT and MRI mCSA change scores (CCC = 0.779). Relative to MRI, pQCT imaging is a valid technique for measuring both mid-thigh mCSA at a single time point and mCSA changes following a resistance training intervention.

Evaluation of lumbar paraspinal muscles degeneration and fatty infiltration in dynamic sagittal imbalance based on magnetic resonance imaging.

PURPOSE: To explore degeneration and fatty infiltration (FI) of lumbar paraspinal muscles in patients with dynamic sagittal imbalance (DSI) and the relationship between lumbar paraspinal muscles degeneration, fatty infiltration and severity of the disease. METHODS: We recruited 41 DSI patients and selected 22 lumbar spinal stenosis (LSS) patients without osphyalgia as controls. All patients received magnetic resonance imaging (MRI) scan and DSI patients also received pre-walk and post-walk X-rays. DSI patients were divided into 2 subgroups according to their symptom improvement after conservative treatment. We calculated rmCSA and FI of the lumbar paraspinal muscles. The rmCSA and FI between DSI and control and between DSI subgroups were compared by t test. The regression analysis was used to explore the risk factors influencing disease severity. Receiver operating characteristic (ROC) curves and area under curves (AUCs) were used to evaluate the severity of the disease. RESULTS: In comparison of rmCSA and FI between DSI and control, there are significant differences of most muscles. In comparison of rmCSA between two subgroups, there are significant differences of most muscles, while in comparison of FI, only muscles in L4 segment have significant different. In logistic regression analysis, total rmCSA and total FI are risk factors influencing disease severity. ROC curves shows that total rmCSA and total FI both achieve an AUC greater than 0.7. CONCLUSION: Compared with control, DSI patients have degeneration and fatty infiltration of the lumbar paraspinal muscles. The degeneration and fatty infiltration are risk factors influencing disease severity. The total rmCSA and total FI can be used as an indicator to determine whether a patient has severe DSI.

How mechanics of individual muscle-tendon units define knee and ankle joint function in health and cerebral palsy-a narrative review.

This study reviews the relationship between muscle-tendon biomechanics and joint function, with a particular focus on how cerebral palsy (CP) affects this relationship. In healthy individuals, muscle size is a critical determinant of strength, with muscle volume, cross-sectional area, and moment arm correlating with knee and ankle joint torque for different isometric/isokinetic contractions. However, in CP, impaired muscle growth contributes to joint pathophysiology even though only a limited number of studies have investigated the impact of deficits in muscle size on pathological joint function. As muscles are the primary factors determining joint torque, in this review two main approaches used for muscle force quantification are discussed. The direct quantification of individual muscle forces from their relevant tendons through intraoperative approaches holds a high potential for characterizing healthy and diseased muscles but poses challenges due to the invasive nature of the technique. On the other hand, musculoskeletal models, using an inverse dynamic approach, can predict muscle forces, but rely on several assumptions and have inherent limitations. Neither technique has become established in routine clinical practice. Nevertheless, identifying the relative contribution of each muscle to the overall joint moment would be key for diagnosis and formulating efficient treatment strategies for patients with CP. This review emphasizes the necessity of implementing the intraoperative approach into general surgical practice, particularly for joint correction operations in diverse patient groups. Obtaining in vivo data directly would enhance musculoskeletal models, providing more accurate force estimations. This integrated approach can improve the clinicians' decision-making process and advance treatment strategies by predicting changes at the muscle and joint levels before interventions, thus, holding the potential to significantly enhance clinical outcomes.

Biceps brachii muscle cross-sectional area measured by ultrasonography is independently associated with one-month mortality: A prospective observational study.

PURPOSE: Studies examining mortality in palliative care units are limited. We aimed to investigate the mortality and associated factors including ultrasonographic muscle parameters in hospitalized palliative patients with a subgroup analysis of older patients. METHODS: A prospective-observational study. We recorded the demographics, number of diseases, diagnoses, and the Charlson comorbidity index (CCI), palliative performance scale (PPS), and nutritional risk screening-2002 (NRS-2002) scores. We noted the nutritional parameters and mortality. We measured the subcutaneous fat thickness (SFT), muscle thickness (MT), and cross-sectional area (CSA) of the rectus femoris and biceps brachii using ultrasonography. RESULTS: We enrolled 100 patients (mean age: 73.2 ± 16.4 years, 53%: female). One-month mortality was 42%. The non-survivors had significantly higher malignancy, increased CCI and NRS-2002 scores, lower required energy intake, calorie sufficiency rate, and biceps brachii SFT, MT, and CSA than the survivors. The independent mortality predictors were malignancy and biceps brachii CSA while the PPS score and malignancy were significantly associated with mortality in the older subgroup. CONCLUSION: The malignancy and biceps brachii CSA might have prognostic value in predicting mortality in palliative patients. This was the first study investigating the mortality-associated factors including ultrasonographic muscle measurements of both the lower and upper limbs in a palliative care center.

The Effects of Creatine Supplementation Combined with Resistance Training on Regional Measures of Muscle Hypertrophy: A Systematic Review with Meta-Analysis.

The purpose of this paper was to carry out a systematic review with a meta-analysis of randomized controlled trials that examined the combined effects of resistance training (RT) and creatine supplementation on regional changes in muscle mass, with direct imaging measures of hypertrophy. Moreover, we performed regression analyses to determine the potential influence of covariates. We included trials that had a duration of at least 6 weeks and examined the combined effects of creatine supplementation and RT on site-specific direct measures of hypertrophy (magnetic resonance imaging (MRI), computed tomography (CT), or ultrasound) in healthy adults. A total of 44 outcomes were analyzed across 10 studies that met the inclusion criteria. A univariate analysis of all the standardized outcomes showed a pooled mean estimate of 0.11 (95% Credible Interval (CrI): -0.02 to 0.25), providing evidence for a very small effect favoring creatine supplementation when combined with RT compared to RT and a placebo. Multivariate analyses found similar small benefits for the combination of creatine supplementation and RT on changes in the upper and lower body muscle thickness (0.10-0.16 cm). Analyses of the moderating effects indicated a small superior benefit for creatine supplementation in younger compared to older adults (0.17 (95%CrI: -0.09 to 0.45)). In conclusion, the results suggest that creatine supplementation combined with RT promotes a small increase in the direct measures of skeletal muscle hypertrophy in both the upper and lower body.

Relationship between the thickness of erector spinae muscles and mortality in patients with pulmonary tuberculosis.

BACKGROUND: Skeletal muscle mass is a known predictor of mortality in older patients. However, its relationship with tuberculosis is unclear. Skeletal muscle mass is determined by the cross-sectional area of erector spinae muscle (ESMCSA). Additionally, the erector spinae muscle thickness (ESMT) is an easier measurement than ESMCSA. This study investigated the relationship of ESMT and ESMCSA with mortality in tuberculosis patients. METHODS: We retrospectively collected the data of 267 older patients (age ≥65 years) who were hospitalized due to tuberculosis at the Fukujuji Hospital from January 2019 to July 2021. This included 40 patients with 60-day mortality (the death group) and 227 patients with 60-day survival (the alive group). Here, we assessed the correlations between ESMCSA and ESMT, and the data were compared between the two groups. RESULTS: ESMT had a strong proportional relationship with ESMCSA (r = 0.991, p < 0.001). ESMCSA (median 670.2 mm2 [interquartile range (IQR): 585.1-760.9] vs. 914.3 mm2 [717.6-1141.6], p < 0.001) and ESMT (median 16.7 mm [15.4-18.6] vs. 21.1 mm [18.0-25.5], p < 0.001) were significantly lower in the patients in the death group than those of patients in the alive group. A multivariable Cox proportional hazard model for 60-day mortality showed significantly independent differences in ESMT (hazard ratio [HR] 0.870 [95% confidence interval (Cl): 0.795-0.952], p = 0.003) and ESMCSA (HR 0.998 [95% Cl: 0.996-0.999], p = 0.009). CONCLUSIONS: This study demonstrated a strong correlation between ESMCSA and ESMT, which were risk factors for mortality in patients with tuberculosis. Therefore, using ESMT is easier to predict mortality than ESMCSA.

High prevalence of sarcopenia and myosteatosis in patients undergoing hemodialysis.

Background and purpose: Sarcopenia is highly prevalent (28.5-40.3%) in patients undergoing hemodialysis and leads to poor clinical outcomes. However, the association between muscle quality and sarcopenia in patients receiving hemodialysis remains unclear. Therefore, we aimed to explore the association between muscle cross-sectional area (CSA) and proton-density fat-fraction (PDFF) in patients with sarcopenia undergoing hemodialysis. Methods: Seventy-six patients undergoing hemodialysis for > 3 months were enrolled. Their handgrip strength (HGS), short physical performance battery (SPPB) performance, and appendicular skeletal muscle mass index (ASMI) were measured. Sarcopenia was defined using the Asian Working Group for Sarcopenia 2019 consensus update. All patients underwent quantitative magnetic resonance imaging. CSA and PDFF were measured for the thigh, trunk, and gluteus muscles. Results: The prevalence of probable, confirmed, and severe sarcopenia in this study was 73.7%, 51.3%, and 22.4%, respectively. Older age (OR: 1.061, P < 0.003); lower body mass index (BMI) (OR: 0.837, P = 0.008), albumin (OR: 0.765, P = 0.004), prealbumin (OR: 0.987, P = 0.001), predialysis blood urea nitrogen (BUN) (OR: 0.842, P < 0.001), predialysis creatinine (OR: 0.993, P < 0.001), phosphorus (OR: 0.396, P = 0.047); lower CSA of the thigh (OR: 0.58, P = 0.035), third lumbar (L3) trunk (OR: 0.37, P = 0.004), gluteus minimus and medius (OR: 0.28, P = 0.001), and gluteus maximus (OR: 0.28, P= 0.001); and higher PDFF of the thigh (OR: 1.89, P = 0.036) and L3 trunk (OR: 1.71, P = 0.040) were identified as sarcopenia risk factors. The gluteus minimus and medius CSA was lower in patients with sarcopenia than in those without after adjusting for age and BMI (OR: 0.37, P = 0.017). Higher thigh (P = 0.031) and L3 trunk (P = 0.006) muscle PDFF were significantly associated with lower HGS. Furthermore, higher thigh (P = 0.011) and L3 trunk (P = 0.010) muscle PDFF were also inversely correlated with lower ASMI. Conclusion: Our findings demonstrate the high prevalence of sarcopenia and myosteatosis in patients undergoing hemodialysis and might trigger a paradigm shift in intervention strategies for patients receiving hemodialysis.

Comprehensive Analyses of Muscle Function, Lean and Muscle Mass, and Myofiber Typing in Mice.

Skeletal muscle disorders commonly affect the function and integrity of muscles. Novel interventions bring new potential to rescue or alleviate the symptoms associated with these disorders. In vivo and in vitro testing in mouse models allows quantitative evaluation of the degree of muscle dysfunction, and therefore, the level of potential rescue/restoration by the target intervention. Several resources and methods are available to assess muscle function and lean and muscle mass, as well as myofiber typing as separate concepts; however, a technical resource unifying these methods is missing. Here, we provide detailed procedures for analyzing muscle function, lean and muscle mass, and myofiber typing in a comprehensive technical resource paper. Graphical abstract.

A Cross-Sectional Study on Gluteal Muscles in Patients with Ankylosing Spondylitis at Different Stages of Hip Involvement.

Hip involvement in ankylosing spondylitis (AS) is associated with severe functional impairment, and early diagnosis can improve the disease prognosis. We investigated gluteal muscle cross-sectional area (CSA) and radiodensity at different stages of hip involvement and their associations with AS-related clinical and laboratory parameters. This cross-sectional study included 83 patients with AS and 83 age- and sex-matched controls. Patients with AS were divided into three groups according to the Bath Ankylosing Spondylitis Radiology Hip Index system. The CSA and radiodensity of the gluteus maximus, medius, and minimus muscles were measured using computed tomography images. Muscle parameters were compared, and their relationships with clinical and laboratory parameters were evaluated. For the gluteus maximus, patients with AS had a lower CSA than controls, regardless of the degree of hip involvement. For the gluteus medius and minimus, patients with moderate/advanced hip involvement had significantly lower CSA and radiodensity than those with mild to no hip involvement. The severity of hip involvement was negatively associated with muscle parameters. CSA of the gluteus maximus decreased in early-stage hip involvement without any changes in radiographs, while radiodensity decreased in the later stages. Muscle parameters on computed tomography may be a more sensitive indicator than radiographic findings.

Effect of vitamin D3 vs. calcifediol on VDR concentration and fiber size in skeletal muscle.

INTRODUCTION: This study sought to examine the effect of vitamin D3 (VD3) 3200 IU/d, calcifediol (HyD) 20mcg/d, or placebo on intramyonuclear vitamin D receptor (VDR) concentration, muscle fiber cross-sectional area (FCSA), and muscle satellite cell activation. MATERIALS AND METHODS: It was conducted on a subset of the VD3 (n = 12), HyD (n = 11), and placebo (n = 13) groups who participated in the 6-month randomized controlled HyD Osteopenia Study in postmenopausal women. Baseline and 6-month vastus lateralis muscle cross sections were probed for VDR, fiber type I and II, and PAX7 (satellite cell marker) using immunofluorescence. RESULTS: Baseline mean ± SD age was 61 ± 4 years and serum 25-hydroxyvitamin D (25OHD) level was 55.1 ± 22.8 nmol/L. Baseline characteristics did not differ significantly by group. Six-month mean ± SD 25OHD levels were 138.7 ± 22.2 nmol/L (VD3), 206.8 ± 68.8 nmol/L (HyD), and 82.7 ± 36.1 nmol/L (placebo), ANOVA P < 0.001. There were no significant group differences in 6-month change in VDR concentration (ANOVA P = 0.227). Mean ± SD percent 6-month changes in type I FCSA were 20.5 ± 32.7% (VD3), - 6.6 ± 20.4% (HyD), and - 0.3 ± 14.0% (placebo, ANOVA P = 0.022). Type II FCSA or PAX7 concentration did not change significantly by group (all P > 0.358). CONCLUSION: This study demonstrated no significant change in intramyonuclear VDR in response to either form of vitamin D vs. placebo. Type I FCSA significantly increased with VD3, but not with HyD at 6 months. As type I fibers are more fatigue resistant than type II, enlargement in type I suggests potential for improved muscle endurance. Although HyD resulted in the highest 25OHD levels, no skeletal muscle benefits were noted at these high levels. CLINICAL TRIAL: NCT02527668.

Characteristics of paraspinal muscle degeneration in degenerative diseases of the lumbar spine at different ages.

OBJECTIVE: To analyze the relationship between gender, age, and the degree of lumbar degenerative disease. METHODS: 290 patients with Lumbar spinal stenosis and sciatica were analyzed. Sixty patients without sciatica were collected in the control group. Patient demography including age, gender, body mass index (BMI), serum calcium, and triglyceride level was acquired. The cross-sectional area (CSA) and percentage of fat infiltration area (Intermuscular adipose tissue (IMat%) of paraspinal muscles at the L4-5 level were measured using MRI imaging. The patients were divided into five age groups: A (18-30 years old), B (31-40 years old), C (41-50 years old), D (51-60 years old), and E (> 60 years old). Analysis of variance (ANOVA) and LSD was used to analyze differences among subgroups. Student's t-test was used to compare MCSA and fat CSA in the two groups. P < 0.05 was statistically significant. RESULTS: The paraspinal muscle CSA (MCSA) was significantly smaller in women (P < 0.05). Older age was associated with less MCSA and greater fatty infiltration in erector spinae and multifidus (MF) muscle (P < 0.05). Serum calcium and BMI were positively correlated with CSA of erector spinae muscle (P < 0.05), but not with muscle fat infiltration (P > 0.05). Although there was no significant difference in MCSA between the two groups, the fat infiltration (IMat%) in the disease group was significantly higher than in the control group (p < 0.05). CONCLUSION: Lumbar degenerative diseases caused the degeneration of the paravertebral muscles, which mainly resulted in increased intramuscular fat infiltration, rather than changes in the overall MCSA.

Associations of muscle size and fatty infiltration with bone mineral density of the proximal femur bone.

Purpose: To investigate the relationship of muscle atrophy and fat infiltration around the hip joint with areal bone mineral density (aBMD) in each subregion of the proximal femur. Materials and methods: In total, 144 participants (66 women and 78 men) were examined by quantitative computed tomography (QCT), and areal bone mineral density (aBMD) of the femoral neck (FN), trochanter (TR), and intertrochanter (IT) of the proximal femur were obtained. The cross-sectional area (CSA) and proton density fat fraction (PDFF) of the gluteus maximus (G.MaxM), gluteus medius (G.MedM), gluteus minimus (G.MinM), and iliopsoas (IliopM) were obtained via magnetic resonance imaging (MRI) using the mDIXON-Quant sequence. A multivariate generalized linear model was used to evaluate the correlation of the CSA and PDFF of muscles with aBMD in all subregions of the proximal femur. Results: The FN integral (Int) aBMD was significantly associated with the G.MaxM CSA (men: P = 0.002; women: P = 0.008) and PDFF (men: P < 0.001; women: P = 0.047). Some muscle indexes were related to the FN aBMD in males or females, including the CSA of G.MedM, G.MinM, and IliopM as well as the PDFF of IliopM and G.MinM. Associations of hip muscle parameters with the TR Int aBMD in both males and females were observed, including G.MaxM CSA (men: P < 0.001; women: P = 0.028) and G.MaxM PDFF (men: P = 0.031; women: P = 0.038). Other muscle indexes, including G.MedM and IliopM, were related to the TR aBMD, mainly affecting the aBMD of TR cortical (Cort) and TR Int. The IT Int aBMD and IT Cort aBMD showed significant correlation with the muscle indexes of G. MaxM, IliopM, and G.MedM, including the PDFF and CSA in males and females. Further, more indicators of the G.MedM and IliopM correlated with the TR and IT aBMD compared to the FN aBMD. Conclusions: The CSA of gluteus muscles and iliopsoas had a positive association with the aBMD in the proximal femur, and the PDFF of gluteus muscles and iliopsoas had a negative correlation with the aBMD in the proximal femur. In addition, there was an interaction of the proximal femur aBMD with the muscle size and fatty infiltration of hip muscles.

L-Carnitine Combined with Leucine Supplementation Does Not Improve the Effectiveness of Progressive Resistance Training in Healthy Aged Women.

OBJECTIVES: To evaluate the effect of L-carnitine (LC) in combination with leucine supplementation on muscle strength and muscle hypertrophy in aged women participating in a resistance exercise training (RET) program. DESIGN/SETTING/PARTICIPANTS: Thirty-seven out of sixty (38.3% dropout) healthy women aged 60-75 years (mean 67.6 ± 0.7 years) completed the intervention in one of three groups. One of the supplemented groups received 1 g of L-carnitine-L-tartrate in combination with 3 g of L-leucine per day (LC+L group; n = 12), and the second supplemented group received 4 g of L-leucine per day (L group; n = 13). The control group (CON group; n = 12) received no supplementation. INTERVENTION: All three groups completed the same RET protocol involving exercise sessions twice per week for 24 weeks. MEASUREMENTS: Before and after the experiment, participants performed isometric and isokinetic muscle strength testing on the Biodex dynamometer. The cross-sectional areas of the major knee extensors and total thigh muscles were assessed using magnetic resonance imaging. Fasting serum levels of insulin-like growth factor-1 (IGF-1), myostatin and decorin, and plasma levels of total carnitine (TC) and trimethylamine-N-oxide (TMAO) levels were measured. RESULTS: The 24-week RET significantly increased muscle strength and muscle volume, but the group and time interactions were not significant for the muscle variables analyzed. Plasma total carnitine increased only in the LC+L group (p = 0.009). LC supplementation also caused a significant increase in plasma TMAO, which was higher after the intervention in the LC+L group than in the L (p < 0.001), and CON (p = 0.005) groups. The intervention did not change plasma TMAO concentration in the L (p = 0.959) and CON (p = 0.866) groups. After the intervention serum decorin level was higher than before in both supplemented groups combined (p = 0.012), still not significantly different to post intervention CON (p = 0.231). No changes in serum IGF-1 and myostatin concentrations and no links between the changes in blood markers and muscle function or muscle volume were observed. CONCLUSIONS: LC combined with leucine or leucine alone does not appear to improve the effectiveness of RET.

The possible predictive value of muscle ultrasound in the diagnosis of ICUAW in long-term critically ill patients.

PURPOSE: Intensive Care Unit acquired weakness (ICUAW) occurs commonly. Muscular ultrasonography allows visualization and classification of muscle characteristics. The aims of this study were to evaluate peripheral and respiratory muscles, their changes during long-term ICU stays, and the possible diagnostic predictive value of ICUAW as compared to the Medical Research Council strength score (MRC-SS). MATERIALS: 50 mechanically ventilated patients were enrolled. Within 48 h after ICU admission (T1), patients underwent muscular ultrasound (rectus femoris cross sectional area (RFCSA), pennation angle, diaphragm, and parasternal intercostal). All the same measures were repeated at days 3 (T3) and 7 (T7). Muscle strength assessment was performed using the MRC-SS. RESULTS: No significant differences were found regarding age, sex, weight, height, or BMI values, in those who developed ICUAW according to MRC-SS. The RF pennation angle, however, significantly changed between T7-T1 in patients who developed ICUAW and was. Found to be the best predictor of ICUAW. CONCLUSIONS: Quadriceps and respiratory muscles were altered within the first week of mechanical ventilation. The loss of pennation angle offers high diagnostic accuracy for ICUAW, allowing for an earlier diagnosis before patients became able to perform volitional tests.

Relationship between sarcopenia classification and thigh muscle mass, fat area, muscle CT value and osteoporosis in middle-aged and older Japanese adults.

Sarcopenia is one of the most important health issues in today's ageing society. As an evaluation method, computed tomography (CT) is an effective means of assessing not only the quantity but also the quality of skeletal muscle. We aimed to examine the relationship between sarcopenia severity and muscle/fat area, and osteoporosis. 321 patients (116 men and 205 women, mean age 77.2 ± 7.1 years, age range 53-96 years) who visited the Integrated Healthy Aging Clinic from 2016 to 2017 were included in this study. Based on the Asia Working Group for Sarcopenia2019 criteria, patients were divided into four groups: normal group, low-functional group (with normal skeletal muscle mass, but reduced muscle strength or physical function), sarcopenia group, and severe sarcopenia group. We measured the skeletal muscle (SM), intermuscular adipose tissue (IMAT), and subcutaneous adipose tissue (SAT) areas and the CT attenuation values (CTV) using cross sections of the mid-thigh CT. We also measured bone mineral density. Then, we compared each result among the four groups. We found a significant decrease in SM area in both men and women with sarcopenia (p < 0.001 for both sexes). In women, a decrease in SAT area was observed in the sarcopenia group (p < 0.001), and an increase in IMAT was observed in the low functional group (p < 0.001). The CTV decreased in men with sarcopenia and severe sarcopenia; similarly, women in the low functional and severe sarcopenia groups had decreased CTV (p < 0.001 for both sexes). An association between sarcopenia and osteoporosis in men was detected (p = 0.004). By using not only muscle mass but also fat mass and CTV, we were able to better examine the pathogenesis of sarcopenia and differences between men and women in Japanese middle-aged and older adults.

Influence of Long-Lasting Static Stretching on Maximal Strength, Muscle Thickness and Flexibility.

Background: In animal studies long-term stretching interventions up to several hours per day have shown large increases in muscle mass as well as maximal strength. The aim of this study was to investigate the effects of a long-term stretching on maximal strength, muscle cross sectional area (MCSA) and range of motion (ROM) in humans. Methods: 52 subjects were divided into an Intervention group (IG, n = 27) and a control group (CG, n = 25). IG stretched the plantar flexors for one hour per day for six weeks using an orthosis. Stretching was performed on one leg only to investigate the contralateral force transfer. Maximal isometric strength (MIS) and 1RM were both measured in extended knee joint. Furthermore, we investigated the MCSA of IG in the lateral head of the gastrocnemius (LG) using sonography. Additionally, ROM in the upper ankle was investigated via the functional "knee to wall stretch" test (KtW) and a goniometer device on the orthosis. A two-way ANOVA was performed in data analysis, using the Scheffé Test as post-hoc test. Results: There were high time-effects (p = 0.003, ƞ² = 0.090) and high interaction-effect (p < 0.001, ƞ²=0.387) for MIS and also high time-effects (p < 0.001, ƞ²=0.193) and interaction-effects (p < 0.001, ƞ²=0,362) for 1RM testing. Furthermore, we measured a significant increase of 15.2% in MCSA of LG with high time-effect (p < 0.001, ƞ²=0.545) and high interaction-effect (p=0.015, ƞ²=0.406). In ROM we found in both tests significant increases up to 27.3% with moderate time-effect (p < 0.001, ƞ²=0.129) and high interaction-effect (p < 0.001, ƞ²=0.199). Additionally, we measured significant contralateral force transfers in maximal strength tests of 11.4% (p < 0.001) in 1RM test and 1.4% (p=0.462) in MIS test. Overall, there we no significant effects in control situations for any parameter (CG and non-intervened leg of IG). Discussion: We hypothesize stretching-induced muscle damage comparable to effects of mechanical load of strength training, that led to hypertrophy and thus to an increase in maximal strength. Increases in ROM could be attributed to longitudinal hypertrophy effects, e.g., increase in serial sarcomeres. Measured cross-education effects could be explained by central neural adaptations due to stimulation of the stretched muscles.

Sex-related differences in sternocleidomastoid muscle morphology in healthy young adults: A cross-sectional magnetic resonance imaging measurement study.

BACKGROUND: Changes in sternocleidomastoid (SCM) muscle cross-sectional area (CSA) and volume may contribute to neck-related concussion symptoms and whiplash-associated disorders. Magnetic resonance imaging (MRI) data on healthy SCM morphology can provide information that may lead to targeted treatment protocols. OBJECTIVES: To examine sex-related differences in MRI-based SCM CSA, SCM volume and neck area in healthy young adults, to analyze associations between measurements and participant variables and to assess inter-rater reliability for measurement quantification. DESIGN: Cross-sectional study. METHODS: 13 males and 14 females underwent MRI scans. Slices obtained from C3-C7 were analyzed by three raters. SCM CSA at C4, total SCM volume from C3-C7 and neck area at C4 were quantified. Measurements were calculated as absolute and normalized values by body mass. Multivariable regression was used to analyze associations between normalized measurement values and participant variables. Inter-rater reliability was determined using intraclass correlation coefficients (ICC). RESULTS: Females had significantly lower normalized overall average SCM CSA (mean difference 1.3 mm2/kg (95% CI 0.4-2.2, p = 0.006) and total SCM volume (mean difference 140.8 mm3/kg (95% CI 66.1-215.5, p < 0.001) than males. Regression models indicated female sex was associated with lower normalized overall average SCM CSA (p = 0.004) and total SCM volume (p < 0.001). Inter-rater reliability was excellent for SCM CSA (ICC3,3 = 0.909), SCM volume (ICC3,3 = 0.910) and neck area (ICC3,3 = 0.995). CONCLUSIONS: These results enhance our understanding of sex-related differences in SCM morphology and will inform future research and clinical practice related to cervical muscle injury.

Early Life Factors Associated with Lean Body Mass in Spanish Children: CALINA Study.

Early life is critical for the programming of body composition. The literature links perinatal factors with fat mass development and its future effects (e.g., obesity); however, little evidence exists between early life factors and lean body mass (LBM). This study follows up on a cohort of 416 Spanish children at ages six to eight, previously evaluated at birth in the CALINA study. Here, we studied the association between early life factors, LBM, and limb strength. Parental origin/nutritional status, maternal smoking during pregnancy, gestational diabetes/weight gain/age, birth weight (BW), early feeding, and rapid weight gain (RWG) were collected from primary care records. Bioimpedance analysis, dual-energy X-ray absorptiometry, peripheral quantitative computed tomography, and a handgrip/standing long jump test were used to assess fat-free mass index (FFMI), total lean soft tissue mass index (TLSTMI), muscle cross-sectional area index (MCSAI), and limb strength, respectively. In girls, maternal smoking, gestational age, and BW were positively associated with FFM/LSTM. In boys, the parents' BMI, BW, and RWG were positively associated with FFM/LSTM. BW was associated with handgrip strength in both. Maternal BMI in girls and RWG in boys were negatively associated with the standing long jump. Early life programming plays a key role in determining LBM in children.