Musculoskeletal Structures Research Articles

Hypergraph modeling of complex interactions: Applications from human musculoskeletal structures to complex system dynamics.

The musculoskeletal network is a complex system of different types of nodes and edges interacting with each other. Although there is a wealth of knowledge about the anatomical components of the human body and the connections between them, the interdependence of these components as a system remains largely unexplored. This study aims to understand the structure of musculoskeletal networks by using hypergraphs as a model of the musculoskeletal system with many-to-many connections. We used both pairwise and hypergraph-based embedding methods to learn the connectivity of muscles. Experiments demonstrated the superiority of the proposed hypergraph-based method over pairwise methods in distinguishing the specific roles of the muscles connecting different body parts.

Enhancing postural stability in musculoskeletal quadrupedal locomotion through tension feedback for CPG-based controller

A central pattern generator (CPG)-based controller enhances the adaptability of quadrupedal locomotion, for example, by controlling the trunk posture. The conventional CPG-based controllers with attitude control often utilized the posture angle as feedback information. However, if the robot's body is as soft as a musculoskeletal structure, it can detect the over-tilting of the trunk based on proprioceptive information of the muscles. In general, proprioceptive information such as muscle tension changes more rapidly than posture angle information. Therefore, a feedback loop based on proprioceptive information has great potential to respond to sudden disturbances that occur during locomotion over uneven terrain. In this research, we proposed a CPG-based controller utilizing the tension of soft pneumatic artificial muscles (PAMs). Musculoskeletal quadruped robots driven by PAMs are so soft, which prevents over-tilting of the trunk because the soft leg acts like a suspension. In addition, tension, one of the proprioceptive information of PAMs, exhibits high sensitivity to changes in trunk posture because the soft body's motion easily is affected by over-tilting of the trunk. To validate the efficacy of the proposed controller, we conducted numerical simulations with a simple quadruped model and experiments with a musculoskeletal quadruped robot. As a result, the tension feedback is not effective for posture stabilization on flat terrain whereas it is effective on uneven terrain. Moreover, the tension feedback improved the running velocity over uneven terrain. These results will enhance the locomotion capability of musculoskeletal quadruped robots, advancing their practical application.

Low-carbon transformation and ecological safeguarding in the Yellow River Basin: Integrating biomechanical and biological insights

This research, titled “Low-carbon transformation and ecological safeguarding in the Yellow River Basin: Integrating biomechanical and biological insights” explores the interplay between economic activities, land use changes, and environmental impact. Through regression analyses and assessments of land use alterations, the study identifies significant provincial variations in factors influencing carbon emissions. In addition to the socio-economic factors, the research incorporates insights from biomechanics and biology, drawing parallels between the ecological systems of the Yellow River Basin and biological processes such as energy efficiency and resource allocation in living organisms. For instance, just as organisms optimize energy usage and adapt to external stressors, the proposed low-carbon strategies aim to optimize resource use and improve the resilience of the basin’s ecosystem. Proposed strategies for low-carbon transformation provide a practical roadmap for sustainable development, informed by biological principles like ecological balance, regeneration, and the importance of maintaining biodiversity. These principles reflect how biomechanical systems, such as musculoskeletal structures, balance energy expenditure and repair to maintain functionality under strain, similar to how ecosystems must manage resource cycles to withstand environmental stressors. The integration of socio-economic indicators, alongside biological and biomechanical insights, underscores the need for region-specific policies that consider not only economic factors but also the natural regenerative capacities of the ecosystem. The study suggests that, like biological systems that repair and adapt to maintain homeostasis, the Yellow River Basin’s ecological processes can be guided by sustainable management practices to ensure long-term resilience and stability. In conclusion, the research contributes valuable insights to the global discourse on balancing economic growth with ecological preservation in the ecologically vital Yellow River Basin, highlighting how the integration of biomechanical and biological principles can enhance both ecological safeguarding and low-carbon transformation strategies.

Lower limb joint loading during high-impact activities: implication for bone health.

Osteoporosis results in low-trauma fractures affecting millions globally, in particular elderly populations. Despite the inclusion of physical activity in fracture prevention strategies, the optimal bone-strengthening exercises remain uncertain, highlighting the need for a deeper understanding of lower limb joint loading dynamics across various exercise types and levels. This study examines lower limb joint loading during high-impact exercises across different intensities. A total of 40 healthy, active participants were recruited (mean ± SD: age of 40.3 ± 13.1yr; height 1.71 ± 0.08m; and mass 68.44 ± 11.67kg). Motion capture data and ground reaction forces of 6 different exercises: a self-selected level of walking, running, countermovement jump, squat jump, unilateral hopping, and bilateral hopping were collected for each participant. Joint reaction forces were estimated using lower body musculoskeletal models developed in OpenSim. Running and hopping increased joint forces compared to walking, notably at the hip (83% and 21%), knee (134% and 94%), and ankle (94% and 77%), while jump exercises reduced hip and ankle loading compared to walking (36% and 19%). Joint loading varied with exercise type and intensity, with running faster increasing forces on all joints, particularly at the hip. Sprinting increased forces at the hip but lowered knee and ankle forces. Higher jumps intensified forces on all joints, while faster hopping reduced forces. The wide variation of lower limb joint loading observed across the exercises tested in this study underscores the importance of implementing diverse exercise routines to optimize overall bone health and strengthen the musculoskeletal structure. Practitioners must therefore ensure that exercise programs include movements that are specifically suitable for their intended purpose.

Ultrasound Screening of Achilles Tendon, Patellar Tendon, and Plantar Fascia for Pain Development in Collegiate Athletes: A Multi-institutional Prospective Evaluation.

Diagnostic ultrasound can evaluate musculoskeletal structures for abnormalities that correlate with tendinopathy and fasciopathy. Previous literature suggests that sonographic screening of tendons and fascia can identify structures that are at risk for developing pain, although this has not been evaluated in collegiate athletes competing in a variety of sports. To evaluate the use of ultrasound for screening the patellar tendon, Achilles tendon, and plantar fascia for time-loss injury in collegiate athletes during a full year. Cohort study; Level of evidence, 2. A total of 242 National Collegiate Athletic Association (NCAA) Division I athletes from 3 institutions participated in this yearlong prospective observational study. Each athlete completed a brief demographic questionnaire, followed by an ultrasound examination of the bilateral patellar tendons, Achilles tendons, and plantar fascia performed at the beginning of the season. Ultrasound examinations assessed for tendon/fascia thickening, hypoechogenicity, and neovascularization. Athletes were monitored for any time-loss injury in these 3 structures throughout a full year. Of the 242 athletes (n = 484 tendon/fascia) evaluated, the patellar tendon had the highest prevalence of sonographic abnormalities (37.4%), followed by the Achilles tendon (10.6%); plantar fascia abnormalities were rare (3.5%). The overall number of tendon/fascia structures that developed injury was low (<5%). The relative risk for a time-loss injury based on an initial abnormal ultrasound screening was 8.8, 17.2, and 13.2 for the patellar tendon, Achilles tendon, and plantar fascia, respectively (P < .01). Negative predictive values (99-99.6) far outweighed positive predictive values (10.3-14). NCAA Division I student-athletes with sonographic abnormalities on initial screening were more likely to develop a time-loss injury in the affected tendon/fascia during the competitive season. Further research on this topic should focus on identifying the specific sonographic abnormalities and their relationship with future injury.

The Effect of Stretching Exercises Applied to Caregivers of Children with Development Disabilities on Musculoskeletal Muscle Mobility and Respiratory Function.

We aimed to investigate the effect of stretching exercises applied to the hamstring, one of the posterior muscle chains, on musculoskeletal flexibility, chest mobility, and respiratory function. Proprioceptive neuromuscular facilitation and static stretching exercises were applied to 30 healthcare personnel caring for children with developmental delays using a crossover randomized study design. Posterior muscle chain mobility was assessed using the popliteal angle test (PAT) for the hamstring muscle, the mobility of the lumbar muscles was assessed using the Schober test (ST), and the mobility of the posterior chain muscles as a whole was assessed using the finger-to-floor distance test. Chest mobility was measured using chest circumference measurements and lung volumes were measured using the pulmonary function test (PFT). The results showed that stretching exercises applied to the hamstrings led to significant improvements in PAT, ST, and chest mobility in the direction of maximal expiration (p < 0.05), without being superior to each other. Ten males (33.3%) and twenty females (66.7%) who met the inclusion criteria were analyzed. The mean age of the participants was 26.6 ± 5.9 years, the mean height was 169.53 ± 8.67 cm, the mean weight was 65.26 ± 12.03 kg, and the mean body mass index was 22.58 ± 3 kg/m2. Chest inspiratory mechanics also showed a low positive correlation with posterior muscle mobility (r = 0.381; p = 0.038). There was no significant change in PAT. Within the framework of the myofascial theory, stretching exercises that can contribute positively to the musculoskeletal and respiratory system structures of healthcare professionals can be recommended and encouraged to healthcare professionals.

Intensity-modulated proton radiotherapy spares musculoskeletal structures in regional nodal irradiation for breast cancer: a dosimetric comparison.

Regional nodal irradiation (RNI) for breast cancer delivers radiation in proximity to the shoulder and torso, and radiation exposure may contribute to long-term upper extremity and postural morbidity. To date, no studies have assessed the differential dosimetric impact of proton versus photon radiation on shoulder and torso anatomy. This study examined clinically relevant musculoskeletal (MSK) structures and assessed the dose delivered with each modality. Ten MSK structures were contoured on IMPT (intensity-modulated proton therapy) and VMAT (volumetric modulated arc therapy) plans for 30 patients receiving RNI. Relevant dose metrics were compared for each of the structures. Intensity-modulated proton therapy dose was calculated using the relative biological effective value of 1.1. Hypo-fractionated plans were scaled to the equivalent dose in 2 Gy fractions (EQD2) using an alpha/beta ratio of four. Wilcoxon signed rank sum tests compared doses. Select three-dimensional and optimised VMAT plans were also informally compared. Each of the 10 structures received a statistically significantly lower dose with the use of IMPT compared with VMAT. Differences were greatest for posterior structures, including the trapezius, latissimus dorsi and glenohumeral joint. Mean absolute differences were as great as 23 Gy (supraspinatus D5cc) and up to 30-fold dose reductions were observed (deltoid D50cc). An average 3.7-fold relative dose reduction existed across all structures. Measures of low/intermediate dose (V15Gy and D50cc) showed the largest differences. Intensity-modulated proton therapy results in statistically lower radiation exposure to relevant shoulder and torso anatomy compared to photon radiation for patients requiring RNI. Prospective study is needed to correlate functional outcomes with radiation dose.

Persistence, not avoidance, is associated with low back pain-An observational cohort study.

Low back pain (LBP) is increasingly understood as a long-lasting condition with a variable course. Avoidance and persistence behaviour have been described to mediate pain persistence by potentially linking psychosocial factors and biomechanics. The resulting maladaptive changes in musculoskeletal structures can result in movement control impairment (MCI). This investigation aimed to observe avoidance and persistence behaviour and MCI in participants with acute LBP over 1 year and explore their association with pain persistence. In this observational cohort study, 165 participants were assessed at five time points: ≤ 1 month (baseline), 2, 3, 6, and 12 months after the onset of acute LBP. Simultaneously collected clinical data such as self-reported outcomes at baseline for avoidance and persistence and assessments of MCI were filled in linear mixed-effects regression models. The mixed-effects analysis revealed for the adjusted model that a one-point increase in persistence scores resulted in a 3.31-point increase in pain intensity while interacting with state anxiety over time (p = 0.05, 95% confidence interval 0.07-6.07). This effect was not found for avoidance behaviour at baseline (p = 0.21) and MCI. The relationship between persistence and pain intensity throughout measurement suggests that continuing usual activities beyond pain, coupled with feelings of distress, may lead to persistent LBP. These results underscore the need for a therapeutic shift toward a multidimensional approach that considers the physical and psychological characteristics of persons with LBP. Screening for activity patterns in acute LBP is critical for providing tailored treatment and counselling. In acute low back pain (LBP), maintaining usual activities despite pain and distress can contribute to the continuation of LBP. Alongside a multidimensional approach that considers physical and psychological factors, attitudes toward daily activities are also important. Screening for both maladaptive and adaptive activity patterns in individuals with acute LBP is essential for effective LBP management, improving patient outcomes, and preventing persistent pain.

Musculoskeletal infections associated with Nocardia species: a case series.

Background: Nocardia is an uncommon pathogen that has been reported to infect musculoskeletal structures. However, studies are largely limited to case reports, and little is known regarding management and outcomes of these infections. Methods: We performed a multicenter retrospective cohort study of adults with culture-confirmed musculoskeletal Nocardia infections at three Mayo Clinic centers in Arizona, Florida, and Minnesota from November 2011 through April2022. Results: Nine cases of Nocardia musculoskeletal infection were identified. Seven (78 %) occurred in men, and the median age was 57.3 years (range 32.6-79.0). Specific infections included native joint septic arthritis with or without associated osteomyelitis ( ), hardware-associated infection ( ), sternal osteomyelitis ( ), pyomyositis ( ), bursitis ( ), and tenosynovitis ( ). Three cases (33 %) were associated with disseminated disease, all three occurring in solid organ transplant recipients. Surgical intervention was performed in all but the bursitis case. Length of treatment varied from 21 d for tenosynovitis to 467 d for osteomyelitis. The 1-year mortality was 22 %, and all fatal cases involved disseminated disease. Conclusion: Patients with localized nocardiosis affecting musculoskeletal structures generally have good outcomes, as opposed to those with disseminated infection. Management often required operative intervention, with one patient experiencing recurrence within 1year.

Practical Use of Ultrasound in Modern Rheumatology-From A to Z.

During the past 20 years, the use of ultrasound (US) in rheumatology has increased tremendously, and has become a valuable tool in rheumatologists' hands, not only for assessment of musculoskeletal structures like joints and peri-articular tissues, but also for evaluation of nerves, vessels, lungs, and skin, as well as for increasing the accuracy in a number of US-guided aspirations and injections. The US is currently used as the imaging method of choice for establishing an early diagnosis, assessing disease activity, monitoring treatment efficacy, and assessing the remission state of inflammatory joint diseases. It is also used as a complementary tool for the assessment of patients with degenerative joint diseases like osteoarthritis, and in the detection of crystal deposits for establishing the diagnosis of metabolic arthropathies (gout, calcium pyrophosphate deposition disease). The US has an added value in the diagnostic process of polymyalgia rheumatica and giant-cell arteritis, and is currently included in the classification criteria. A novel use of US in the assessment of the skin and lung involvement in connective tissue diseases has the potential to replace more expensive and risky imaging modalities. This narrative review will take a close look at the most recent evidence-based data regarding the use of US in the big spectrum of rheumatic diseases.

Enhancing Multi-Object Detection in Ultrasound Images Through Semi-Supervised Learning, Focal Loss and Relation of Frame

ObjectiveTo identify musculoskeletal anatomical structures in real time by using deep learning techniques. MethodsAn automated annotation system based on deep learning neural networks was designed to aid in the real-time identification of anatomical structures. Additionally, novel algorithms aimed at diminishing model training duration while enhancing accuracy were introduced. In this study, we proposed a semi-supervised learning (SSL) approach that substantially reduced annotation time. We also adopted the focal loss (FL) method to enhance the accuracy of challenging structures. Additionally, during the inference stage, we harnessed the temporal continuity of video frames, which involved leveraging information from preceding frames to facilitate recognition of structures in the current image. Training the model through a combination of SSL and FL yielded superior performance compared with supervised learning, while also substantially mitigating any expense linked to annotations. During inference, the incorporation of frame continuity helped to avoid discontinuity and bolster accuracy. ResultsForearm tissue detection was demonstrated by properly configuring the SSL approach, including FL and the filtering threshold. Comparable performance with supervised learning was achieved while only using 30% of the training data. The real-time experimental results also demonstrated that implementing relation of frame reduced the number of missing frames during inference and successfully increased the confidence scores of detected objects. ConclusionThis proposed system has the potential to aid medical professionals in efficiently and effectively diagnosing musculoskeletal disorders, ultimately leading to enhanced patient outcomes.

Ultrasound for pain interventions: peripheral nerve and musculoskeletal structures

Ultrasound for pain interventions: peripheral nerve and musculoskeletal structures

Comparative muscle anatomy of the anuran pelvis and hindlimb in relation to locomotor mode.

Frogs have a highly conserved body plan, yet they employ a diverse array of locomotor modes, making them ideal organisms for investigating the relationships between morphology and locomotor function, in particular whether anatomical complexity is a prerequisite for functional complexity. We use diffusible iodine contrast-enhanced microCT (diceCT) imaging to digitally dissect the gross muscle anatomy of the pelvis and hindlimbs for 30 species of frogs representing five primary locomotor modes, including the first known detailed dissection for some of the world's smallest frogs, forming the largest digital comparative analysis of musculoskeletal structure in any vertebrate clade to date. By linking musculoskeletal dissections and phylogenetic comparative methods, we then quantify and compare relationships between anatomy and function across over 160 million years of anuran evolution. In summary, we have found that bone lengths and pelvic crest sizes are generally not reliable predictors of muscle sizes, which highlights important implications for future palaeontological studies. Our investigation also presents previously unreported differences in muscle anatomy between frogs specialising in different locomotor modes, including several of the smallest frog hindlimb muscles, which are extremely difficult to extract and measure using traditional approaches. Furthermore, we find evidence of many-to-one and one-to-many mapping of form to function across the phylogeny. Additionally, we perform the first quantitative analysis of how the degree of muscle separation can differ between frogs. We find evidence that phylogenetic history is the key contributing factor to muscle separation in the pelvis and thigh, while the separation of shank muscles is influenced more strongly by locomotor mode. Finally, our anatomical 3D reconstructions are published alongside this manuscript to contribute towards future research and serve as educational materials.

Neuropsychiatric considerations in treating anorexia nervosa patients with osteopathic manipulative medicine: a narrative review.

Osteopathic manipulative medicine (OMM) has a growing recognition in serving as an effective treatment topromote adaptation and homeostasis of the body by addressing musculoskeletal, neural, vascular, and lymphatic structures to promote self-healing and regulation. OMM can treat the musculoskeletal tension and sympathetic hyperactivity resulting from the increased cortisol response and hypersensitivity found in varying psychiatric illnesses, including anorexia nervosa (AN). This paper addresses the considerations necessary for treating AN patients with OMM, emphasizing the need to evaluate their abnormal high-level neuronal processing of sensory information, including differences in touch perception compared to the general population. Current literature was gathered utilizing a combination of the following keywords: anorexia nervosa, perception of touch, and osteopathic manipulative medicine/treatment. No literature was found addressing the effects of OMM on treating AN patients. Eight studies addressed the change in perception of touch found in AN patients. Results of the literature review reveal that the perceptions of touch in AN patients are distorted and can lead to reduced perceived pleasantness encountered in social interactions and touch. Specific changes have been found in C-tactile (CT) afferents responsible for the positive effects of touch, thus influencing emotional regulation. The significance of addressing this topic is to provide insight into the pathophysiological processes of AN and to inform physicians of unconventional stimuli that may exacerbate AN symptoms and behaviors. Further study is required to elucidate the role and mechanism of OMM in patients with AN and whether manual therapy could worsen pathological behavior and thinking patterns seen in AN patients. Such studies could include, but are not limited to, examining biological factors such as cortisol levels in AN patients receiving OMM and collecting data about AN patients' thinking patterns and behavior during OMM treatment.

Pain management after thoracotomy with dexamethasone and bupivacaine through a peripleural cather: a randomized controlled trial

IntroductionThoracotomy procedures can result in significant pain and cause nausea/vomiting. Glucocorticoids have anti-emetic and analgesic effects due to their anti-inflammatory and nerve-blocking properties. This study investigates the additive effect of local dexamethasone with bupivacaine as sole analgesic medication through a peripleural catheter after thoracotomy.MethodThe study was conducted as a randomized control trial on 82 patients. Participants were allocated to receive either 2.5 mg/kg of bupivacaine plus 0.2 mg/kg of dexamethasone or 2.5 mg/kg of bupivacaine plus the same amount of normal saline as placebo through a 6 French peripleural catheter implemented above the parietal pleura and beneath the musculoskeletal structure of the chest wall. The primary outcome was the severity of pain 24 h after the operation in the visual analogue scale (VAS) score. Secondary outcomes were the incidence of nausea/vomiting, opioid consumption for pain control, and incidence of any adverse effects.Results: A total of 50 participants were randomized to each group, and the baseline characteristics were similar between the groups. Median of VAS score (6 (3-8) vs. 8 (6-9), p < 0.001), postoperative opioid consumption (9 (36%) vs. 17 (68%) patients, p=0.024), and median length of hospital stay (4 (3-8) vs. 6 (3-12) days, p < 0.001) were significantly lower in the dexamethasone group. However, postoperative nausea/vomiting (p=0.26 for nausea and p=0.71 for vomiting) and surgical site infection (p = 0.55) were similar between the two groups. ConclusionIn thoracotomy patients, administering local dexamethasone + bupivacaine through a peripleural catheter can reduce postoperative pain, analgesic consumption, and length of hospital stay.Trial RegistrationIranian Registry of Clinical Trials (IRCT20220309054226N1, registration date: 3/21/2022.

Muscle-Driven Predictive Physics Simulations of Quadrupedal Locomotion in the Horse.

Musculoskeletal simulations can provide insights into the underlying mechanisms that govern animal locomotion. In this study, we describe the development of a new musculoskeletal model of the horse, and to our knowledge present the first fully muscle-driven, predictive simulations of equine locomotion. Our goal was to simulate a model that captures only the gross musculoskeletal structure of a horse, without specialized morphological features. We mostly present simulations acquired using feedforward control, without state feedback ("top-down control"). Without using kinematics or motion capture data as an input, we have simulated a variety of gaits that are commonly used by horses (walk, pace, trot, tölt, and collected gallop). We also found a selection of gaits that are not normally seen in horses (half bound, extended gallop, ambling). Due to the clinical relevance of the trot, we performed a tracking simulation that included empirical joint angle deviations in the cost function. To further demonstrate the flexibility of our model, we also present a simulation acquired using spinal feedback control, where muscle control signals are wholly determined by gait kinematics. Despite simplifications to the musculature, simulated footfalls and ground reaction forces followed empirical patterns. In the tracking simulation, kinematics improved with respect to the fully predictive simulations, and muscle activations showed a reasonable correspondence to electromyographic signals, although we did not predict any anticipatory firing of muscles. When sequentially increasing the target speed, our simulations spontaneously predicted walk-to-run transitions at the empirically determined speed. However, predicted stride lengths were too short over nearly the entire speed range unless explicitly prescribed in the controller, and we also did not recover spontaneous transitions to asymmetric gaits such as galloping. Taken together, our model performed adequately when simulating individual gaits, but our simulation workflow was not able to capture all aspects of gait selection. We point out certain aspects of our workflow that may have caused this, including anatomical simplifications and the use of massless Hill-type actuators. Our model is an extensible, generalized horse model, with considerable scope for adding anatomical complexity. This project is intended as a starting point for continual development of the model and code that we make available in extensible open-source formats.

Cervical spine positioning patterns amongst hand surgeons: A critical analysis of surgical posture

AimThis study aims to assess the cervical spine positioning of consultant and trainee hand surgeons during standardised hand surgeries, focusing on the prevalence of sustained end-range postures, particularly cervical spine flexion. BackgroundSurgeons often perform procedures that require maintenance of sustained postures for prolonged periods of time. Hand surgeons may be at increased risk of sustained end of range postures, particularly cervical spine flexion. This can lead to strain on the musculoskeletal structures of the neck. Recent evidence suggests a higher incidence of neck dysfunction in hand surgeons, leading to an associated morbidity. MethodsWe examined hand surgeons of all experience levels during 40 common hand surgery procedures. We used real-time dynamic goniometric measurements of neck flexion using the “UPRIGHT GO 2” device and accompanying smartphone app. Neck flexion exceeding 40° was used as the threshold for defining an acceptable neck position. ResultsAnalysis included 20 total subjects at various levels of medical training (SHO n ​= ​6, Registrar n ​= ​9, Consultant n ​= ​5) performing surgeries under different conditions. Maladaptive neck positions were prevalent, with junior surgeons exhibiting such postures for 71 ​% of procedure time compared to 60 ​% for consultants. This underscores the potential contribution of sustained end-range postures to cervical spine dysfunction in hand surgeons, highlighting an early intervention opportunity. Notably, participants reported varied experiences with neck pain and expressed unanimous interest in integrating biofeedback posture devices into surgical training, with a single consultant expressing reservations.

Unsupervised Feature Extraction From Raw Data for Gesture Recognition With Wearable Ultralow-Power Ultrasound.

Wearable ultrasound (US) is a novel sensing approach that shows promise in multiple application domains, and specifically in hand gesture recognition (HGR). In fact, US enables to collect information from deep musculoskeletal structures at high spatiotemporal resolution and high signal-to-noise ratio, making it a perfect candidate to complement surface electromyography for improved accuracy performance and on-the-edge classification. However, existing wearable solutions for US-based gesture recognition are not sufficiently low power for continuous, long-term operation. On top of that, practical hardware limitations of wearable US devices (limited power budget, reduced wireless throughput, and restricted computational power) set the need for the compressed size of models for feature extraction and classification. To overcome these limitations, this article presents a novel end-to-end approach for feature extraction from raw musculoskeletal US data suited for edge computing, coupled with an armband for HGR based on a truly wearable (12 cm2, 9 g), ultralow-power (ULP) (16 mW) US probe. The proposed approach uses a 1-D convolutional autoencoder (CAE) to compress raw US data by 20× while preserving the main amplitude features of the envelope signal. The latent features of the autoencoder are used to train an XGBoost classifier for HGR on datasets collected with a custom US armband, considering armband removal/repositioning in between sessions. Our approach achieves a classification accuracy of 96%. Furthermore, the proposed unsupervised feature extraction approach offers generalization capabilities for intersubject use, as demonstrated by testing the pretrained encoder on a different subject and conducting posttraining analysis, revealing that the operations performed by the encoder are subject-independent. The autoencoder is also quantized to 8-bit integers and deployed on a ULP wearable US probe along with the XGBoost classifier, allowing for a gesture recognition rate ≥ 25 Hz and leading to 21% lower power consumption [at 30 frames/s (FPS)] compared to the conventional approach (raw data transmission and remote processing).

Mesenchymal Stromal Cells for the Enhancement of Surgical Flexor Tendon Repair in Animal Models: A Systematic Review and Meta-Analysis.

Flexor tendon lacerations are primarily treated by surgical repair. Limited intrinsic healing ability means the repair site can remain weak. Furthermore, adhesion formation may reduce range of motion post-operatively. Mesenchymal stromal cells (MSCs) have been trialled for repair and regeneration of multiple musculoskeletal structures. Our goal was to determine the efficacy of MSCs in enhancing the biomechanical properties of surgically repaired flexor tendons. A PRISMA systematic review was conducted using four databases (PubMed, Ovid, Web of Science, and CINAHL) to identify studies using MSCs to augment surgical repair of flexor tendon injuries in animals compared to surgical repair alone. Nine studies were included, which investigated either bone marrow- or adipose-derived MSCs. Results of biomechanical testing were extracted and meta-analyses were performed regarding the maximum load, friction and properties relating to viscoelastic behaviour. There was no significant difference in maximum load at final follow-up. However, friction, a surrogate measure of adhesions, was significantly reduced following the application of MSCs (p = 0.04). Other properties showed variable results and dissipation of the therapeutic benefits of MSCs over time. In conclusion, MSCs reduce adhesion formation following tendon injury. This may result from their immunomodulatory function, dampening the inflammatory response. However, this may come at the cost of favourable healing which will restore the tendon's viscoelastic properties. The short duration of some improvements may reflect MSCs' limited survival or poor retention. Further investigation is needed to clarify the effect of MSC therapy and optimise its duration of action.

Marathon Health Pitfalls: What Every Runner Needs to Know

Introduction and Purpose: Long-distance running, especially marathons, tests human endurance and physical limits. While the benefits of marathon running are well-documented, the associated health risks often go unnoticed. This review aims to synthesize current knowledge on the health risks and complications faced by marathon runners, providing crucial insights for both amateur and professional athletes.State of Knowledge: Marathon running imposes significant stress on the cardiovascular system, musculoskeletal structure, and metabolic processes. Issues such as acute myocardial injury, overhydration leading to hyponatremia, and musculoskeletal injuries are prevalent. The review also examines less common but severe risks like rhabdomyolysis and marathon-related cardiac arrests. Despite the robust fitness levels of runners, these health risks remain a serious concern, necessitating preventive strategies and proper health monitoring.Summary: Marathon runners must be aware of the potential health risks associated with prolonged endurance activities. Precautionary measures, including tailored training programs, dietary adjustments, and regular medical check-ups, are essential to mitigate these risks. Additionally, further research is required to develop more effective interventions and guidelines that can safeguard the health of marathon participants. This review underscores the need for a balanced approach that respects the physiological demands of marathon running while ensuring the health and safety of the runners.