The LightBack device applies controlled axial compression forces on the femur to replicate posterior femoral displacement and provide mechanical stimulation to the gluteal region. This study aimed to examine the effects of LightBack application on sciatic nerve stiffness and posterior chain flexibility in healthy, physically active individuals. A randomized within-subject, contralateral-leg controlled trial was conducted with 25 healthy, physically active participants (49 lower limbs; n=25 in the LightBack testing leg and n=24 in the contralateral control leg). Sciatic nerve stiffness was assessed using shear wave elastography (SWE), and posterior chain flexibility was evaluated using the Active Knee Extension (AKE) and Active Straight Leg Raise (ASLR) tests. All outcomes were measured immediately before and after each intervention session. Linear mixed-effect models demonstrated a significant time×leg interaction for all variables (p<0.05). In the LightBack testing leg, AKE improved from 26.72° to 19.04° (p<0.001) and ASLR from 22.08° to 15.96° (p<0.001). Sciatic nerve stiffness decreased from 33.84 to 28.79kPa (p<0.001), while shear wave velocity declined from 3.27 to 2.99m/s (p<0.001). LightBack application resulted in significant improvements in posterior chain flexibility and reductions in sciatic nerve stiffness in healthy individuals. Further studies are warranted to explore these relationships and their implications for clinical and performance settings.

Fe/N-doped hollow carbon nanozymes for synergistic chemo-photothermal-catalytic therapy via tumor microenvironment remodeling.

Semitendinosus force-joint angle relationship after anterior cruciate ligament reconstruction with semitendinosus tendon.

This study aimed to investigate the relationship between medial gastrocnemius (MG) shear modulus and viscosity, as measured using shear wave elastography (SWE), and the capacity for rapid force production, specifically the rate of torque development (RTD). Twenty-nine healthy young men participated in this study. The passive shear modulus and viscosity (viscosity coefficient) of the MG were measured using SWE. Viscosity was quantified at 15° of plantarflexion, whereas shear modulus was measured at 0° and 15° of plantarflexion. Participants performed maximal isometric plantarflexion at 0°. RTD was calculated over 0-50 (RTD50) and 0-100 ms (RTD100) and was normalized to peak torque. The relationships between MG viscosity, MG shear modulus, RTD, and peak torque were analysed using Pearson product-moment correlation coefficients. Viscosity at 15° of plantarflexion was significantly positively correlated with RTD50 (r = 0.507, p = 0.005) and RTD100 (r = 0.399, p = 0.032). Shear modulus at 0° of plantarflexion was also significantly correlated with RTD50 (r = 0.479, p = 0.009) and RTD100 (r = 0.377, p = 0.044). No significant correlations were found between peak torque and any viscoelastic parameters. Shear modulus at 15° of plantarflexion did not correlate with RTD. This study provides initial evidence that skeletal muscle viscosity may be crucial in determining rapid force production. In addition to acting as a property characterized by velocity-dependent resistance, muscle viscosity may contribute to stable and efficient force transmission during the initial phase of contraction.

To compare the immediate effects of two neurodynamic mobilization techniques (flossing vs. tensioning) on the sciatic nerve and hamstring muscle tissues, using different stretching intensities. Twenty physically active volunteers performed a randomized, study comprising seven conditions (six stretching + control). Interventions included static stretching (SS), neurodynamic tensioning (TENS), and neurodynamic flossing (FLOS), applied at 100% (pain threshold) or 90% maximal range of motion, using 5 × 60-s sets. Shear wave elastography (SWE) was used to assess sciatic nerve and biceps femoris stiffness before and immediately after the interventions. Measurements included flexibility tests (passive knee extension (PKE), stand and reach (SR), slump), and hamstring strength (MVIC) alongside with electromyography (EMG). SWE of the sciatic nerve showed a significant condition × time interaction (p < 0.001), with a significant decrease only after flossing at maximal intensity (FLOS100); The biceps femoris (BF) shear wave velocity (SWV) decreased over time (p = 0.004) independently of the condition. Flexibility outcomes significantly improved after all stretching interventions (p < 0.001). Nevertheless, FLOS100 produced significantly greater improvements in sciatic nerve mobility than SS at maximal intensity (p = 0.017). MVIC significantly decreased from PRE to POST (p = 0.009) across all conditions, with no condition × time interaction (p = 0.991). The EMG activity remained unchanged for BF muscle while semitendinosus (ST) EMG showed a significant decrease over time (p = 0.017). Neurodynamic flossing at maximal intensity reduced sciatic nerve stiffness and mobility in asymptomatic individuals. These neural adaptations suggest flossing should be prioritized for neural tissue, while all stretching techniques similarly affect muscle stiffness.

Site-dependent differences in placental stiffness in extrachorial placenta: implications for shear wave elastography assessment.

This study aimed to examine the effects of a 12‑week hamstrings dynamic stretching (DS) program on joint flexibility, muscle strength, and musculoskeletal properties in the stretched limb, with the non‑stretched limb assessed for comparison. The study comprised 18 healthy young adults (12 males, 6 females) who performed hamstrings DS on one leg three times per week for 12 weeks, with the contralateral leg serving as the control. Pre- and post-intervention assessments included knee extension range of motion (KEROM), peak passive torque during KEROM (stretch tolerance), muscle stiffness, and knee flexor strength. Muscle stiffness was evaluated using shear-wave elastography targeting the biceps femoris (BF). Knee flexor strength was assessed using the rate of torque development (RTD) and isokinetic knee flexion torque. KEROM significantly increased in the DS condition (p = 0.025; d = 0.61), with no significant change in the control condition (p = 0.55; d = 0.15). Peak passive torque significantly increased following DS (p = 0.041; d = 0.68), with no change in the contralateral limb (p = 0.21; d = 0.21). BF stiffness significantly decreased in the DS condition and remained unchanged in the contralateral limb (70° knee flexion: DS, p < 0.01, d = 0.79; control, p = 0.30, d = 0.30; 50° knee flexion: DS, p = 0.044, d = 0.55; control, p = 0.18, d = 0.34. RTD and isokinetic knee flexion strength did not change significantly in either condition. Twelve weeks of hamstrings DS enhanced stretch tolerance, reduced muscle stiffness, and improved joint flexibility in the stretched limb, with no notable changes observed in the contralateral limb. Name of trial registry Effects of training and conditioning methods on mechanical properties of skeletal muscle Identifying number (URL) UMIN000051819 ( https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000058080 ) Date of registration 5th Aug 2023.

Shearwave elastography (SWE) to detect hyperglycaemic changes in the placenta (a pilot feasibility study).

This study aimed to investigate the value of shear wave elastography (SWE) and an ultrasonic multi-parameter score in identifying chronic kidney disease (CKD) stage ≥ III (moderate-to-severe CKD) in patients with known CKD. A single-centre cross-sectional study was conducted, enrolling 152 patients with CKD (staged I-V according to estimated glomerular filtration rate). Conventional ultrasound parameters (renal length, parenchymal thickness, echogenicity) and SWE measurements (Young's modulus [YM] in kPa) of the renal cortex and medulla were obtained. The ultrasonic multi-parameter score was calculated using a standardised rubric. Receiver operating characteristic curve analysis was performed to evaluate the diagnostic performance of SWE cortical YM and the multi-parameter score for identifying CKD stage ≥ III. The study included 23 patients with stage I CKD, 45 with stage II, 44 with stage III, 15 with stage IV and 25 with stage V. Shear wave elastography cortical YM (area under the curve [AUC]: 0.894) and the multi-parameter score (AUC: 0.870) showed promising discrimination for stage ≥ III CKD. Cortical YM demonstrated a specificity of 0.912 and a sensitivity of 0.671. Shear wave elastography cortical YM has high specificity, supporting its potential role in the rule-in of moderate-to-severe CKD. The ultrasonic multi-parameter score also shows clinical value for severity stratification. However, the relatively low sensitivity limits its utility for rule-out purposes. Not applicable.

Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease with progressive bile duct injury, inflammation, and fibrosis. Matrix metalloproteinases (MMPs) contribute to extracellular matrix remodeling but their circulating profile and clinical relevance in early-stage PBC remain incompletely defined. We characterized circulating MMPs in early-stage PBC and related them to non-invasive fibrosis and portal hemodynamics. Forty-six patients with early-stage PBC and 31 healthy controls were studied. Plasma MMP-2, -3, -7, -9, -10, and -26 were quantified by ELISA; liver stiffness was measured by point shear-wave elastography and portal flow indices by Doppler ultrasound. Compared with controls, PBC patients showed higher MMP-7 (p < 0.0001), MMP-2 (p = 0.0007), and MMP-10 (p = 0.046). MMP-7 correlated with liver stiffness (R = 0.68, p < 0.001) and demonstrated the highest discriminatory performance for significant fibrosis defined as LSM > 5.56kPa (AUC = 0.800, p < 0.001). In exploratory regression analyses, higher MMP-7 concentrations remained associated with significant fibrosis after adjustment for age, whereas APRI and FIB-4 did not show significant discriminatory performance in ROC analysis. Early-stage PBC is therefore associated with a distinct plasma MMP profile, and MMP-7 may serve as a practical biomarker of fibrogenesis, supporting its use for monitoring disease progression.

Acute dehydration impairs performance, but its effects on resting neuromuscular and tissue mechanics are unclear. We tested whether baseline hydration status and exercise-induced sweat loss alter the resting neuromechanical phenotype of the rectus femoris (RF) as well as skin, subcutaneous tissue (subQ), and fascia overlying the RF. Thirty physically active men were randomized to hydration guidance (EXP) or habitual intake (CON). Hydration was verified weekly using first-morning urine specific gravity (USG), with targets of USG < 1.018 (EXP) and USG > 1.018 (CON). Participants performed continuous cycling at 50% maximal power output (Wmax) until ~3% body mass loss. Shear-wave elastography quantified tissue shear modulus (kPa), and tensiomyography assessed RF twitch-derived contractile properties (Dm, Tc, Tr) before and immediately after exercise. SWE data were analyzed using mixed design repeated-measures ANOVA; TMG outcomes were analyzed using non-parametric tests. Baseline measures did not differ between groups. No significant group, time, or interaction effects were observed for RF muscle, skin, or subQ shear modulus. In contrast, fascia shear modulus showed a significant time effect, while TMG outcomes did not change significantly from pre- to post-exercise (all p > 0.05). Deep fascia showed a significant main effect of time, with decreased shear modulus post-exercise (F(1, 21) = 5.06, p = 0.035, η2p = 0.194; Δ = 1.25 kPa; d = 0.41; 95% CI [0.04, 0.78]), independent of hydration group. Under moderate-intensity cycling with approximately 3% body mass loss, we did not detect significant hydration-group differences or significant pre-post changes in resting RF twitch-derived contractile properties or in RF muscle, skin, and subQ shear modulus. Fascia shear modulus decreased after exercise irrespective of hydration group. These findings should be interpreted cautiously: the study was underpowered to detect small effects, and the fascial finding emerged from an exploratory, layer-specific analysis without correction for multiple comparisons. It should therefore be regarded as preliminary and hypothesis-generating, requiring confirmation in adequately powered, pre-registered studies.

Fontan-associated liver disease (FALD) is a fibrotic liver disease in individuals with Fontan physiology. This study sought to determine the efficacy of treatment with udenafil, a phosphodiesterase type 5 inhibitor, for reducing liver congestion leading to a decreased liver stiffness and reduction in serologic biomarkers of liver fibrosis. In patients enrolling in the FUEL trial open label extension, liver stiffness measurements were obtained by ultrasound shear wave elastography (SWE) and magnetic resonance elastography (MRE); serum markers of liver fibrosis were measured by the Enhanced Liver Fibrosis (ELF) score. Change in liver stiffness and ELF score after 12 months of udenafil treatment were analyzed. In 88 subjects, 36 were previously treated with udenafil and 52 were udenafil-naïve. The cohort's baseline liver stiffness was elevated by SWE, mean 2.0 ± 0.4m/sec (adult upper limit normal 1.5m/sec), and MRE, mean 5.3 ± 1.2kPa (adult upper limit normal 2.8kPa). After 12 months of udenafil treatment, there was no change in SWE (post-treatment mean 1.9 ± 0.3m/sec, p = 0.28) nor change in MRE (post-treatment mean 5.2 ± 0.97kPa, p = 0.68). The cohort's baseline ELF score was elevated at 10.4 ± 1.0 according to values correlating with liver fibrosis in other diseases. ELF score decreased at 12 months to 9.8 ± 0.8 (p < 0.0001). Liver stiffness did not change following 12 months of udenafil treatment, but ELF scores significantly decreased. Further study is needed to understand the relationship of ELF score to age, but these results suggest the possibility that udenafil may alter the overall Fontan fibrotic milieu.

Association between infrapatellar fat pad stiffness and gait-related mechanical characteristics in women with knee osteoarthritis.

BackgroundCongenital aortic stenosis (ConAoS) accounts for approximately 4%–8% of all congenital heart diseases. Chronic pressure overload may result in myocardial stiffening, leading to impaired cardiac filling, reduced contractility and ultimately contributing to the onset of symptomatic heart failure. Shear wave elastography (SWE), using high-frame-rate echocardiography, allows visualisation of myocardial shear waves. By measuring shear wave propagation velocity (SWV), this technique may enable non-invasive assessment of myocardial stiffness. This study aimed to explore the feasibility of SWE in adults with ConAoS and to compare SWV with healthy volunteers (HVs).MethodsIn 68 adult patients with ConAoS—including 17 patients after aortic valve replacement (AVR)—and 19 HVs, high-frame-rate recordings were acquired in the parasternal long-axis view. Custom software was used to measure SWV by manually placing M-mode lines through the interventricular septum after aortic valve closure.ResultsSWE feasibility was 73% in ConAoS patients with a native aortic valve (NV), 53% post-AVR and 100% in HVs. Median SWV was 4.7 m/s (3.2–5.5) in NV patients, 3.7 m/s (3.1–5.4) post-AVR and 3.4 m/s (3.0–4.4) in HVs (p=0.200). Patients with moderate-to-severe ConAoS demonstrated higher SWV compared with HVs (4.7 m/s (3.4–5.6) vs 3.4 m/s (3.0–4.4); p=0.035).ConclusionsSWE is feasible in the majority of ConAoS patients. Higher SWV in moderate-to-severe ConAoS patients, despite preserved diastolic function in most cases, may reflect early myocardial mechanical alterations and provide a promising non-invasive marker for myocardial stiffening. Further technical optimisation and cross-platform validation are essential for clinical translation.

Hepatologist-Driven Screening for Obstructive Sleep Apnea in Patients With MASLD Using a Modified STOP-Bang Questionnaire: The SOMA Model.

Aim Metabolic and alcohol-associated liver disease (MetALD) is a newly defined category of steatotic liver disease. It remains unclear whether the severity of fibrosis differs between MASLD-predominant and ALD-predominant MetALD. This study aimed to compare liver stiffness measurements (LSM) using shear wave elastography (SWE) and non-imaging non-invasive liver disease assessments (NILDAs) between these subtypes. Methods In this single-center cross-sectional study, participants with MetALD were stratified into MASLD-predominant (n=176) and ALD-predominant (n=72) groups. Significant fibrosis was defined as a ≥8 kPa. We also compared non-imaging NILDAs (FIB-4 index, NAFLD fibrosis score, Fibrotic NASH index, MAF-5 score, and LiverRisk score) between the two groups. Results No significant differences were observed in LSM (6.35 vs. 6.13 kPa, p=0.1209) or the prevalence of significant fibrosis (36.3% vs. 26.3%, p=0.1308) between the MASLD-predominant and ALD-predominant groups. Similarly, other non-imaging NILDAs, including the Fibrotic NASH index and MAF-5 score, showed no significant differences in the proportion of analyses using clinical cut-offs. In contrast, the proportion of patients with a high FIB-4 index was significantly higher in the ALD-predominant group than in the MASLD-predominant group (18% vs. 30.8%, p=0.0331). Multivariate and decision tree analyses identified the AST levels as the most impacted independent factor of a high FIB-4 index in the ALD-predominant group (OR 1.033, 95%CI 1.011-1.058, p=0.0028). Conclusion Fibrosis severity as assessed by SWE and most non-imaging NILDAs is comparable between MASLD-predominant and ALD-predominant MetALD, supporting their management as a unified clinical entity regarding liver fibrosis. However, the FIB-4 index may overestimate the fibrosis risk in ALD-predominant MetALD due to an alcohol-induced AST elevation.

This study aimed to investigate retrobulbar biomechanical and microvascular changes associated with increasing axial length in myopic eyes using shear wave elastography and a quantitative vascularity index. In this prospective cross-sectional study, 99 eyes from 99 adults were classified into three groups according to axial length: <24.00mm (Group 1), 24.00-25.99mm (Group 2), and ≥ 26.00mm (Group 3). All participants underwent comprehensive ophthalmologic and ultrasonographic evaluations. Shear wave elastography was used to quantify the stiffness of the optic nerve and adjacent retrobulbar fat tissue. Retrobulbar microvascularity was assessed using ultra-microangiography, with color pixel percentage measured as a vascularity index. No significant differences in tissue stiffness were observed among axial length groups (all p > 0.05). However, the vascularity index differed significantly between groups (p = 0.026) and remained independently associated with axial length after adjusting for age and sex (p = 0.041), suggesting progressive reduction in retrobulbar microvascularity, reflected by lower vascularity index values, with increasing axial elongation. Optic nerve diameter significantly decreased with increasing axial length (p = 0.010). These findings indicate that axial elongation in myopic eyes is associated with significant retrobulbar microvascular changes without corresponding alterations in tissue stiffness.

Boiling Histotripsy Ex Vivo in Human Liver Metastases of Various Origin.

Helmet loads have been identified as a source of neck pain in fighter pilots. To minimize risk for neck pain, the effect of helmets on cervical spine biomechanics must be understood. In-vivo methods are difficult and invasive, so finite element modeling (FEM) techniques have been utilized recently to understand neck pathology development. Accurate muscle forces are crucial for physiologically relevant results. Therefore, this study evaluated the relationship between helmet loads and cervical muscle forces using two FEM muscle activation strategies. A validated cervical spine model was altered to include a fighter pilot's helmet load and muscle activations. The following simulations were analyzed: a no-helmet (NH) and helmet (H) conditions using both proportional-integral-derivative (PID) and shear wave elastography (SWE) techniques to estimate muscle forces to stabilize the head in a neutral position. Intervertebral disc (IVD) forces and pressures were reported to validate the muscle forces. PID and SWE methods produced different muscle activation patterns, with PID recruiting larger muscles first. SWE muscle forces were more closely aligned with EMG data, displaying larger activations in the deep stabilizer muscles. NH model loads suggest that both PID and SWE will produce physiological loads on structures in the spine. The use of SWE allows for more subject- and muscle-specificity in FEM, and the results are more consistent with in-vivo data. With the implementation of SWE-informed FEMs, pain mechanisms may be more accurately predicted which can lead to production of more optimal helmet designs, injury prevention protocols, and individualized rehabilitation strategies.

Shear wave elastography (SWE) is widely used for elasticity imaging, but conventional implementations remain confined to two-dimensional (2D) measurement planes and lack sensitivity to viscosity, an emerging biomarker linking shear wave dissipation and disease progression. The objective of this work is to extend SWE for viscoelasticity imaging beyond the measurement plane through methodological and acquisition-based advances. We introduce a cross-plane acquisition strategy in which multiple measurement planes are recorded per acoustic radiation force (ARF) push to capture dissipation across planes. We perform imaging using recently developed full-waveform inversion (FWI), enhanced with an H1 regularization scheme that stabilizes reconstructions by penalizing spurious oscillations. The method is validated using synthetic datasets generated using a reduced-dimension proof-of-concept model focused on out-of-plane sensitivity under varying inclusion geometries, contrasts, and noise levels. Reconstructions were performed using a multiresolution sequential inversion framework that progressively refines elasticity (G) and viscosity (eta). The cross-plane strategy significantly improved the recovery of viscosity distributions by capturing dissipative behavior between measurement planes, while H1 regularization enhanced stability and suppressed noise-induced artifacts without over smoothing. Elasticity maps remained consistent across all cases, whereas viscosity reconstructions exhibited improved boundary fidelity and reduced ambiguity compared with single-plane configurations. These findings demonstrate the feasibility of reconstructing viscoelastic properties beyond the measurement plane using cross-plane SWE. The proposed framework establishes a pathway toward true volumetric (3D) viscoelastic imaging using standard 2D ultrasound acquisitions.