Search Results (102)

Background: The reliable assessment of cervical muscle morphology is essential for both clinical and research use. However, evidence on the reliability of ultrasound measurements remains limited. Objective: To investigate the intra-rater and test–retest reliability of morphological measurements of the Longus Colli, Sternocleidomastoid, Multifidus Cervicis, and Semispinalis Capitis muscles using musculoskeletal ultrasound. Methods: Cross-sectional area, anteroposterior, and lateral dimensions were assessed using B-mode ultrasound. Anterior neck muscles were scanned in the supine position, while posterior neck muscles were scanned in the prone position. Each muscle was measured three times (to assess intra-rater reliability), which was repeated after 30 min (to assess test–retest reliability). Measurements were also normalized according to BMI and neck circumference. Results: Intra-rater reliability was found to be good to excellent for the Longus Colli (ICC = 0.77–0.92), excellent for the Sternocleidomastoid (ICC = 0.93–0.99), good to excellent for the Semispinalis Capitis (ICC = 0.89–0.97), and moderate to excellent for the Multifidus Cervicis (ICC = 0.69–0.92). Test–retest reliability was found to be moderate to good for the Longus Colli (ICC = 0.73–0.87), good to excellent for the Sternocleidomastoid (ICC = 0.84–0.98), good to excellent for the Semispinalis Capitis (ICC = 0.78–0.95), and good to excellent for the Multifidus Cervicis (ICC = 0.80–0.92). Conclusions: Musculoskeletal ultrasound demonstrates strong reliability for cervical muscle assessment, supporting its clinical use. Full article

Objectives: The aim of this study was to evaluate the impact of four working heights on lumbar biomechanics during wall construction tasks, focusing on work-related musculoskeletal disorders (WMSDs). Methods: Fifteen young male participants performed simulated mortar-spreading and bricklaying tasks while actual body movements were recorded using Inertial Measurement Unit (IMU) sensors. Muscle activities of the lumbar erector spinae (ES), quadratus lumborum (QL), multifidus (MF), gluteus maximus (GM), and iliopsoas (IL) were estimated using a 3D musculoskeletal (MSK) model and measured via surface electromyography (sEMG). The analysis of variance (ANOVA) test was conducted to identify the significant differences in muscle activities across four working heights (i.e., foot, knee, waist, and shoulder). Results: Findings showed that working at foot-level height resulted in the highest muscle activity (7.6% to 40.6% increase), particularly in the ES and QL muscles, indicating an increased risk of WMSDs. The activities of the ES, MF, and GM muscles were statistically significant across both tasks and all working heights (p < 0.01). Conclusions: Both MSK and sEMG analyses indicated significantly lower muscle activities at knee and waist heights, suggesting these as the best working positions (47 cm to 107 cm) for minimizing the risk of WMSDs. Conversely, working at foot and shoulder heights was identified as a significant risk factor for WMSDs. Additionally, the similar trends observed between MSK simulations and sEMG data suggest that MSK modeling can effectively substitute for sEMG in future studies. These findings provide valuable insights into ergonomic work positioning to reduce WMSD risks among wall construction workers. Full article

Core stability is fundamental to posture, balance, and force transmission throughout the kinetic chain. Although traditionally associated with athletic performance, emerging research highlights its broader applicability to recreational fitness. This study investigates the effects of an eight-week core training program on muscle hypertrophy, static balance, and neuromuscular control in recreationally active, non-athletic adults. Participants will undertake a structured intervention comprising progressive triads targeting core stability, strength, and power. Assessment methods include surface electromyography (EMG), ultrasound imaging, three-dimensional force plates, Kinovea motion analysis, and the Satisfaction With Life Scale (SWLS) questionnaire. Expected outcomes include enhanced core muscle activation, improved static balance, and increased core-generated force during overhead medicine ball slam trials. Additionally, the intervention aims to facilitate hypertrophy of the transverse abdominis, internal oblique, and lumbar multifidus muscles, contributing to spinal resilience and motor control. This protocol bridges gaps in core training methodologies and advances their scalability for recreational populations. The proposed model offers a structured, evidence-informed framework for improving core activation, postural stability, muscle adaptation, movement efficiency, and perceived quality of life in recreationally active individuals. Full article

Background/Objectives: The assessment of relationships between trunk muscle activity and thoraco-lumbar movements during sagittal bending has demonstrated that low back pain (LBP) subgroups (flexion pattern and active extension pattern motor control impairment) reveal distinct relationships that differentiate these subgroups from control groups. The study objective was to establish whether such relationships exist during various daily activities. Methods: Fifty participants with non-specific chronic low back pain (NSCLBP) (27 flexion pattern (FP), 23 active extension pattern (AEP)) and 28 healthy controls were recruited. Spinal kinematics were analysed using 3D motion analysis (Vicon™, Oxford, UK) and the muscle activity recorded via surface electromyography during a range of activities (box lift, box replace, reach up, step up, step down, stand-to-sit, and sit-to-stand). The mean sagittal angles for upper and lower thoracic and lumbar regions were correlated with normalised mean amplitude electromyography of bilateral transversus abdominis/internal oblique (IO), external oblique (EO), superficial lumbar multifidus (LM), and erector spinae (ES). Relationships were assessed via Pearson correlations (significance p < 0.01). Results: In the AEP group, increased spinal extension was associated with altered LM activity during box-replace, reach-up, step-up, and step-down tasks. In the FP group, increased lower lumbar spinal flexion was associated with reduced muscle activation, while increased lower thoracic flexion was associated with increased muscle activation. The control group elicited no significant associations. Correlations ranged between −0.812 and 0.754. Conclusions: Differential relationships between muscle activity and spinal kinematics exist in AEP, FP, and pain-free control groups, reinforcing previous observations that flexion or extension-related LBP involves distinct motor control strategies during different activities. These insights could inform targeted intervention approaches, such as movement-based interventions and wearable technologies, for these groups. Full article

Background and Objectives: We conducted a retrospective observational study. Background: While traditional rehabilitation approaches emphasize trunk muscle conditioning, emerging evidence suggests that leg muscle strength plays a critical role in postoperative functional mobility. Previous studies have focused on trunk muscle rehabilitation in patients with adult spinal deformity (ASD). However, recent findings suggest that leg muscle conditioning may be a better predictor of postoperative improvement. Strengthening the gluteal and iliopsoas muscles has been linked to improved sagittal balance, gait stability, and mobility, ultimately leading to enhanced surgical outcomes. This study examines the relationship between the preoperative functional cross-sectional area (FCSA) of trunk and leg muscles and postoperative improvement in mobility, as assessed by the Timed Up and Go (TUG) test, in patients undergoing surgery for ASD. Materials and Methods: Sixty-two patients (57 women, mean age 71.2 ± 7.1 years) who underwent ASD surgery between April 2017 and April 2024 were retrospectively analyzed. The FCSA of key muscles—psoas major (PM), erector spinae (ES), multifidus (MF), gluteus maximus (GM), and gluteus medius (GMed)—was measured using CT images. Patients were categorized into an improvement group and a non-improvement group based on whether they achieved the minimum clinically important difference (MCID) of −2 s in the TUG test 12 months after surgery. Propensity score matching (PSM) was applied to adjust for baseline differences between the groups. A significance level of 5% was used for all comparisons. Results: Thirty-three patients achieved a clinically meaningful improvement in TUG, while 29 did not. Before PSM, patients with worse preoperative TUG and Oswestry Disability Index (ODI) scores showed greater improvements (p < 0.01). After PSM, no significant differences were found between the groups in terms of age, sex, or BMI. However, the improvement group showed significantly greater FCSA values in PM (6.1 ± 2.3 mm² vs. 3.9 ± 1.5 mm², p = 0.021) and GM (19.9 ± 5.9 mm² vs. 15.3 ± 3.9 mm², p = 0.019). Conclusions: This study demonstrates that leg muscle quality, particularly that of the gluteus maximus and psoas major, is a significant predictor of postoperative mobility improvement in patients with ASD. These findings challenge the conventional focus on trunk muscles and suggest the inclusion of leg muscle training in preoperative rehabilitation strategies to enhance surgical outcomes. Full article

Military operators performing vehicle maintenance work are at times subject to onerous tasks such as lifting and transporting heavy loads, potentially in confined spaces. As this presents a risk for developing musculoskeletal injury, it is of interest to evaluate if a passive back-support exosuit could help reduce back muscle load. This study used wireless electromyographic (EMG) sensors to evaluate the biomechanical effects of exosuits during lifting tasks. Ten male participants performed military-relevant lifting tasks with and without wearing the exosuit in randomised orders. The lifting tasks included (1) vertical lifts of different weights (15 and 25 kg) onto different platform heights (0.5 m and 1.2 m) and (2) a lateral walk task across 4 m in a confined space while carrying a 39 kg weight. EMG activities of three back muscle groups (longissimus, iliocostalis, and multifidus) were measured and normalised to maximal isometric back extension tasks. The results showed no significant differences in muscle activation between conditions in most lifting tasks, except for a reduction in longissimus muscle activity when using the exosuit during lateral walking. Individual responses varied substantially, with some participants showing reduced muscle activity, while others did not. These findings highlight the challenges in implementing exosuits in reducing back muscle load during military lifting tasks. While passive back-support exosuits may provide benefits to some users, their effectiveness varies among individuals and may be task-dependent. Full article

This study evaluated attenuation values of lumbar epaxial musculature in dogs with acute spinal pathology using computed tomography (CT) and compared them with values in dogs without spinal disease. Sixty client-owned dogs were included: thirty dogs with thoracolumbar spinal lesions (intervertebral disc herniation) and thirty control dogs without spinal abnormalities. Mean Hounsfield unit (HU) values of epaxial muscles (multifidus–longissimus–iliocostalis group) were measured bilaterally at three lumbar levels for each dog—one level cranial to the lesion, the lesion level, and one level caudal to the lesion; for controls, the corresponding segments were T13, L1, L2, and L3. Dogs with spinal pathology showed a significant local decrease in muscle HU at the lesion site (average ~48 HU) compared to the segment cranial to the lesion (~50–51 HU, p < 0.01). In contrast, control dogs had relatively uniform muscle HU (~52–54 HU) across T13–L3 with no significant differences between these levels. Side to side differences were minimal in both groups. A logistic regression using the HU drop between segments correctly classified ~70% of cases, indicating moderate diagnostic value. Age and breed influenced overall muscle HU; older dogs had lower values (r = –0.39, p = 0.03 in controls), and French Bulldogs showed lower HU than other breeds. In conclusion, dogs with acute thoracolumbar disc herniation exhibit a focal reduction in paraspinal muscle HU at the lesion level. This acute change is subtle but detectable with CT and may serve as an additional indicator of lesion presence or chronicity, although its clinical utility requires further investigation in larger studies. Full article

Background/Objectives: Atrophy of the paraspinal and psoas major muscles is closely linked to sagittal malalignment in adult spinal deformity (ASD). However, most studies overlook the balance between these muscle groups. This study investigates the relationship between trunk muscle balance and sagittal alignment in ASD patients. Methods: A single-institution database was reviewed for patients with sagittal malalignment (PT > 20° and PI–LL > 10°). Standard sagittal parameters were measured based on standing X-rays. The cross-section area (CSA) of trunk posterior muscles (CSA^P: erector spinae and multifidus) and anterior muscles (CSA^A: psoas) at L4 were measured based on a T2-weighted MRI. Patients with prior lateral fusions were excluded. Muscle balance was evaluated by the CSA ratio of trunk posterior to anterior muscles (CSA^P/A). The relationship between sagittal alignment parameters and CSA^P, CSA^A, as well as CSA^P/A were analyzed using linear and quadratic regressions. Akaike information criteria (AIC) compared model fit. Subgroup analyses examined the relationship between sagittal alignment changes and different CSA^P/A levels. Results: A total of 112 patients met inclusion and exclusion criteria. CSA^P correlated linearly with SS (r² = 0.057, p = 0.011), PT (r² = 0.043, p = 0.028), and T4–L1PA mismatch (r² = 0.044, p = 0.027). CSA^A showed no significant linear or quadratic relationships with sagittal spinal alignment parameters. In contrast, CSA^P/A was quadratically associated with LL (r² = 0.056, p = 0.044), SS (r² = 0.134, p < 0.001), PI (r² = 0.096, p = 0.004), L1PA (r² = 0.114, p = 0.001), and T4–L1PA mismatch (r² = 0.094, p = 0.005). Quadratic models of CSA^P/A consistently had higher r² and lower AIC values compared to the linear models of CSA^P for most sagittal alignment parameters, especially in SS, PI, L1PA, and T4–L1PA mismatch (AIC difference ≥4). Higher CSA^P/A is correlated to larger PI (and consequently, larger LL, SS, and L1PA). Conclusions: Trunk posterior–anterior muscle balance (CSA^P/A) demonstrates a stronger relationship with sagittal alignment than individual muscle metrics. Quantitative MRI-based definitions of sarcopenia may need to be adjusted for PI. Full article

Background/Objectives: Functional spinal instability from multifidus dysfunction has been proposed as a mechanism for chronic postsurgical pain. Prior studies reported structural impairments in the lumbar multifidus in patients with chronic low back pain, including a reduced cross-sectional area, muscle thickness, and increased fat infiltration. This preliminary report examined the prevalence of multifidus fat infiltration after Spinal Cord Stimulation (SCS), an established pain management technique. It also assessed inter-rater reliability in evaluating fat infiltration using MRI. Methods: The medical imaging data from four patients with Persistent Spinal Pain Syndrome Type II (PSPS II) treated with SCS were collected. Two independent operators performed the manual segmentation of the multifidus muscle on axial MRI images of the lumbar spine. The fat-to-muscle ratio was quantified and rated using a four-point classification system, categorizing multifidus fat infiltration as normal, mild, moderate, or severe. To assess the reliability of the manual segmentations, inter-rater reliability was determined. Results: The median fat-to-muscle ratio at the levels L2–L3 was 46.12 (Q1–Q3: 44.88–47.35). At the levels L3–L4, L4–L5, and L5–S1, the median values were 50.45 (Q1–Q3: 45.57–52.98), 52.11 (Q1–Q3: 48.81–52.80), and 52.84 (Q1–Q3: 49.09–56.39), respectively. An ICC value of one (95% CI from 0.999 to 1, p < 0.001) was found for inter-rater agreement on the muscle volume of the multifidus muscle. Conclusions: All the patients had moderate-to-severe fat infiltration of the multifidus muscle at each lumbar spinal level. Although time-consuming, the manual segmentation of the multifidus muscle in patients treated with SCS was feasible and yielded excellent inter-rater reliability when determining muscle volume. Future endeavors should focus on the automation of segmentation and classification. Full article

Background/Objectives: Symptomatic intravertebral vacuum cleft (SIVC) is a complication of vertebral compression fractures (VCFs) that leads to persistent pain and deformity. Its prediction remains challenging due to multifactorial causes. Paraspinal muscle fat infiltration has been associated with spinal fracture outcomes but has not been extensively explored in SIVC prediction. Our aim was to develop machine learning (ML) models for predicting SIVC and to evaluate the role of muscle-related variables in improving predictive performance. Methods: Demographic, radiological, and muscle-related variables were collected. ML models—including Logistic Regression, Random Forest, XGBoost, and Multi-Layer Perceptron—were trained and tested under two input conditions: baseline variables (SETTING_1) and baseline plus muscle-related variables (SETTING_2). Model performance was evaluated using accuracy, the area under the receiver operating characteristic curve (AUC), and feature importance analysis. Results: The Random Forest model in SETTING_2, which incorporated muscle-related variables, achieved the highest accuracy (96.6%) and AUC (0.956). Multifidus fatty infiltration (MFfi), erector spinae fatty infiltration (ESfi), and endplate CSA were identified as the most significant predictors. The inclusion of muscle-related variables significantly improved the predictive performance of all ML models. Conclusions: ML models, particularly Random Forest, demonstrated high accuracy in predicting SIVC when muscle-related variables were included. Paraspinal muscle fat infiltration is a critical predictor of SIVC and should be integrated into risk assessment strategies to improve early diagnosis and management. Full article

Background: Non-specific low back pain is a discomfort that affects individuals at any point in their lives. This study’s aim was to determine the effects of myofascial release and joint mobilization on muscle thickness via ultrasonography in individuals experiencing non-specific low back pain. Methods: This double-blinded randomized clinical trial was conducted on 84 participants in three groups: joint mobilization, myofascial release, and a combination of joint mobilization and myofascial release. Data were collected during a two-week treatment regimen (days 1, 4, 8, and 12) and at a one-month follow-up. Ultrasound evaluations were used to measure the thickness of deep lumbar muscles at rest and contraction, i.e., the transverse abdominis (rTrA and cTrA) and lumbar multifidus (rLM and cLM). Repeated-measures ANOVA was utilized to analyze the follow-ups within the groups and among the groups, with post hoc tests conducted to identify specific differences. Results: Significant increases in muscle thickness were observed over time in the transverse abdominis, with improvements in both rTrA (right, p = 0.001; left, p = 0.001) and cTrA (right, p = 0.001; left, p = 0.008). The lumbar multifidus also demonstrated significant changes, with increases in the rLM (right, p = 0.001; left, p = 0.047) and cLM (right, p = 0.004; left, p = 0.037). However, the main effects showed no significant differences in muscle thickness among the groups. Conclusions: Joint mobilization demonstrated increased effectiveness in improving muscle thickness relative to myofascial release and a combination of both treatments for individuals with non-specific low back pain. Full article

Myofascial pain syndrome (MPS) is a common musculoskeletal disorder that significantly affects quality of life. Conventional treatment approaches include pharmacological interventions, physical therapy, and procedures such as dry needling. Among these, ultrasound-guided injections (USGIs) have gained recognition for their precision and therapeutic benefits. Additionally, repetitive peripheral magnetic stimulation (rPMS) has emerged as a non-invasive neuromodulatory technique for pain management. This perspective article examines the physiological mechanisms and clinical applications of USGIs and rPMS, particularly in the lumbar multifidus muscle, and explores their potential synergistic effects. MPS is often associated with chronic muscle dysfunction due to energy depletion, leading to persistent pain and motor impairment. USGIs play a crucial role in restoring muscle perfusion, disrupting pain cycles, and providing diagnostic insights in real time. In parallel, rPMS modulates neuromuscular activation, enhances endogenous pain control, and promotes functional recovery. Ultrasound guidance enhances the precision and effectiveness of interventions, such as dry needling, interfascial plane blocks, and fascial hydrodissection, while rPMS complements these strategies by facilitating neuromuscular reconditioning and reducing pain via central and peripheral mechanisms. The preliminary findings suggest that combining multifidus USGIs with rPMS results in significant pain relief and functional improvements in patients with chronic low back pain. Integrating USGIs with rPMS represents a promising multimodal strategy for managing MPS. By combining targeted injections with non-invasive neuromodulation, clinicians may optimize therapeutic outcomes and provide sustained relief for patients with chronic musculoskeletal pain. Further research is needed to refine treatment protocols and assess the long-term efficacy. Full article

Purpose: Impaired balance leads to loss of function, e.g., the inability to walk safely. Therefore, restoring balance is a common goal of rehabilitation after a stroke. An innovative motor imaging and robotic device, the Erigo^®Pro walking table, was used to improve balance in patients who had suffered an acute stroke. Materials and Methods: Sixty-six stroke patients in the acute phase with an average age of 64.85 ± 18.62 years were randomly assigned to one of three groups (22 subjects each) and treated with different therapies (conventional, conventional with Erigo^®Pro, and conventional with Erigo^®Pro enriched with motor imaging). The duration of therapy was two weeks. Patients were assessed before and after completion of therapy. The study used the trunk stability test and the Berg Balance Scale to assess balance, and the Riablo™ device to measure static balance. In addition, an assessment of the superficial tension of the transversus abdominis and multifidus muscles was performed. The clinical trial registration URL unique identifier was NCT06276075. Results: In each of the groups studied, the therapies applied resulted in significant improvement in functional assessment of trunk stability and balance (TCT < 0.001 and BBS < 0.001). The assessment of balance in the frontal (p = 0.023) and sagittal (p = 0.074) planes with the Riablo™ device confirmed the superiority of motor imaging-enhanced therapy at the level of a statistical trend. The tension of the transversus abdominis was higher at the second measurement (M = 14.41; SE = 3.31). Conclusions: Motor imagery-enhanced therapy is most important, both for trunk stability and functional improvement of body balance parameters and for increasing transversus abdominis muscle tension. Full article

Background: the validity and reliability of the front plank test (FPT) have been studied in young adults but not in adults aged 34 to 60 years. The aim of this study was to analyze the criterion-related validity and reliability of the front plank test (FPT) for evaluating trunk musculature in adults according to sex and age groups. Methods: a repeated measures design was used to study the reliability of the FPT. A total of 84 adults aged 18–62 years performed trunk muscular force tests and the FPT. Criterion-related validity was assessed using repeated measures ANOVA. Reliability was examined by ICC, error measurements, and Bland–Altman analysis across sex and age groups. Results: significant differences in the activation of the rectus abdominis and external oblique muscles were found compared with the erector spinae and multifidus muscles (p < 0.001). No correlations were found between FPT time and physical activity or rate of perceived exertion at the end (p > 0.05). Low and moderate correlations were found with body fat percentage, trunk fat mass percentage, and external oblique, regardless of sex and age groups (p < 0.05). Extremely high reliability was found regardless of sex and age groups (ICC > 0.98), with low error measurements (RMSE = 11.93–18.73; %CV = 4.91–6.33; SEE = 11.45–16.84). MDC90 values indicated no real change between T1 and T2. Conclusion: FPT is a valid and reliable test for assessing trunk musculature in adults regardless of sex and age groups. Full article

Neonatal mammals must rapidly adapt to significant physiological changes during the transition from the intrauterine to extrauterine environments. This adaptation, particularly in the metabolic and respiratory systems, is essential for survival. MicroRNAs (miRNAs) are small noncoding RNAs that regulate various physiological and pathological processes by binding to the 3′ untranslated regions of mRNAs. This study aimed to identify miRNAs involved in the early extrauterine adaptation of neonatal piglets and explore their functions. We performed small RNA sequencing on six tissues (heart, liver, spleen, lung, multifidus muscle, and duodenum) from piglets 24 h before birth (day 113 of gestation) and 6 h after birth. A total of 971 miRNA precursors and 1511 mature miRNAs were identified. Tissue-specific expression analysis revealed 881 tissue-specific miRNAs and 164 differentially expressed miRNAs (DE miRNAs) across the tissues. Functional enrichment analysis showed that these DE miRNAs are significantly enriched in pathways related to early extrauterine adaptation, such as the NFκB, PI3K/AKT, and Hippo pathways. Specifically, miR-22-3p was significantly upregulated in the liver post-birth and may regulate the PI3K/AKT pathway by targeting AKT3, promoting gluconeogenesis, and maintaining glucose homeostasis. Dual-luciferase reporter assays and HepG2 cell experiments confirmed AKT3 as a target of miR-22-3p, which activates the AKT/FoxO1 pathway, enhancing gluconeogenesis and glucose production. Furthermore, changes in blood glucose and liver glycogen levels in newborn piglets further support the role of miR-22-3p in glucose homeostasis. This study highlights the importance of miRNAs, particularly miR-22-3p, in the early extrauterine adaptation of neonatal piglets, offering new insights into the physiological adaptation of neonatal mammals. Full article