Muscle Injury Research Articles

Novel therapeutic activities of dragon blood from palm tree Daemonorops draco for the treatment of chronic diabetic wounds

BackgroundThe clinical efficacy of Jinchuang Ointment, a traditional Chinese medicine (TCM), in treating chronic non-healing diabetic wounds has been demonstrated over the past decades. Both in vitro and in vivo angiogenic activities have been reported for its herbal ingredients, including dragon blood from the palm tree Daemonorops draco and catechu from Uncaria gambir Roxb. Additionally, crude extracts of dragon blood have exhibited hypoglycemic effects not only in animal studies but also in cell-based in vitro assays.ResultsOur findings indicate that crude dragon blood extract promotes the differentiation of myoblasts into myotubes. Partially purified fractions of dragon blood crude extract significantly enhance the expression of muscle cell differentiation-related genes such as myoG, myoD, and myoHC. Our results also demonstrate that crude extracts of dragon blood can inhibit platelet-derived growth factor-induced PAI-1 expression in primary rat vascular smooth muscle cells, thereby favoring changes in hemostasis towards fibrinolysis. Consistent with previous reports, reduced expression of plasminogen activator inhibitor 1 (PAI-1) accelerates wound healing. However, further separation resulted in a significant loss of both activities, indicating the involvement of more than one compound in these processes. Stem cells play a crucial role in muscle injury repair. Neither dragon blood nor catechu alone stimulated the proliferation of human telomerase reverse transcriptase (hTERT)-immortalized and umbilical cord mesenchymal stem cells. Interestingly, the proliferation of both types of stem cells was observed when crude extracts of dragon blood and catechu were present together in the stem cell growth medium.ConclusionsDragon blood from D. draco offers multifaceted therapeutic benefits for treating chronic nonhealing diabetic wounds from various perspectives. Most drugs in Western medicine consist of small molecules with defined ingredients. However, this is not the case in TCM, as the activities of dragon blood reported in this study. Surprisingly, the activities documented here align with descriptions in ancient Chinese medical texts dating back to A.D. 1625.

Myositis and Its Mimics: Guideline Updates, MRI Characteristics, and New Horizons.

Myositis is defined as inflammation within skeletal muscle and is a subcategory of myopathy, which is more broadly defined as any disorder affecting skeletal muscle. Myositis may be encountered as a component of autoimmune and connective tissue disease, where it is described as idiopathic inflammatory myopathy. Myositis can also be caused by infections, as well as toxins and drugs, including newer classes of medications. MRI plays an important role in the diagnosis and evaluation of patients with suspected myositis, but many entities may have imaging features similar to myositis and can be considered myositis mimics. These include muscular dystrophies, denervation, deep venous thrombosis, diabetic myonecrosis, muscle injury, heterotopic ossification, and even neoplasms. In patients with suspected myositis, definitive diagnosis may require integrated analysis of imaging findings with clinical, laboratory, and pathology data. The objectives of this article are to review the fundamental features of myositis, including recent updates in terminology and consensus guidelines for idiopathic inflammatory myopathies, the most important MRI differential diagnostic considerations for myositis (i.e., myositis mimics), and new horizons, including the potential importance of artificial intelligence and multimodal integrated diagnostics in the evaluation of patients with muscle disorders.

Eccentric Muscle Strengthening Using Maximal Contractions Is Deleterious in Knee Osteoarthritis: A Randomized Clinical Trial.

Objectives: To show the superiority of eccentric versus concentric strengthening in terms of improving quadriceps strength in knee osteoarthritis (OA), a randomized controlled study was conducted to perform 12 sessions of either eccentric or concentric isokinetic muscle strengthening over 6 weeks. Methods: We recruited males and females, aged between 40 and 70 years, with predominantly unilateral femorotibial OA. Exclusion criteria were having a prosthesis, inflammatory arthritis or flare-up of OA, symptomatic patellofemoral OA, cardiovascular or pulmonary disease that could be a contraindication to the study treatment, and any pathology that could cause muscle weakness. The primary endpoint was the between-group difference in change in maximum concentric isokinetic knee extension peak torque (PT) at 60°/s on the OA side at 6 weeks. Secondary endpoints were between-group difference in change in concentric hamstring PT at 60°/s; eccentric quadriceps and hamstring PT at 30°/s; 10 m and 200 m walking speeds; pain and functional status (WOMAC score) at 6 weeks and 6 months. Results: The sample consisted of 11 females and 27 males, with a mean age of 57.7 ± 7.52 years and a body mass index (BMI) of 25.95 ± 3.93 kg/m2. Quadriceps strength increased more at 6 weeks in the concentric than the eccentric group with no statistical difference. There was a rate of 25% major adverse events in the eccentric group. Conclusions: Eccentric training resulted in a smaller improvement in quadriceps strength than concentric training and was associated with a high risk of muscle injury, particularly to the hamstring muscles.

MiR-27b-3p reduces muscle fibrosis during chronic skeletal muscle injury by targeting TGF-βR1/Smad pathway

BackgroundFibrosis is a significant pathological feature of chronic skeletal muscle injury, profoundly affecting muscle regeneration. Fibro-adipogenic progenitors (FAPs) have the ability to differentiate into myofibroblasts, acting as a primary source of extracellular matrix (ECM). the process by which FAPs differentiate into myofibroblasts during chronic skeletal muscle injury remains inadequately explored.Methodmouse model with sciatic nerve denervated was constructed and miRNA expression profiles between the mouse model and uninjured mouse were analyzed. qRT/PCR and immunofluorescence elucidated the effect of miR-27b-3p on fibrosis in vivo and in vitro. Dual-luciferase reporter identified the target gene of miR-27b-3p, and finally knocked down or overexpressed the target gene and phosphorylation inhibition of Smad verified the influence of downstream molecules on the abundance of miR-27b-3p and fibrogenic differentiation of FAPs.ResultFAPs derived from a mouse model with sciatic nerves denervated exhibited a progressively worsening fibrotic phenotype over time. Introducing agomiR-27b-3p effectively suppressed fibrosis both in vitro and in vivo. MiR-27b-3p targeted Transforming Growth Factor Beta Receptor 1 (TGF-βR1) and the abundance of miR-27b-3p was negatively regulated by TGF-βR1/Smad.ConclusionmiR-27b-3p targeting the TGF-βR1/Smad pathway is a novel mechanism for regulating fibrogenic differentiation of FAPs. Increasing abundance of miR-27b-3p, suppressing expression of TGF-βR1 and inhibiting phosphorylation of smad3 presented potential strategies for treating fibrosis in chronic skeletal muscle injury.

Platelet-Poor versus Platelet-Rich Plasma for the Treatment of Muscle Injuries.

Muscle injury in sport results in significant lost time and potential for reinjury for athletes. Autologous blood product, namely, platelet-rich plasma (PRP), has been investigated for possible augmentation of the treatment timeline with prevention of reinjury; however, conflicting results have been identified. A growing body of basic science and clinical literature is forming that supports the use of platelet-poor plasma (PPP) for muscle injury. The purpose of this study was to provide a background of the basic science of PRP versus PPP for muscle injury and to identify and review the clinical evidence for both autologous blood products, including the author's clinical experience utilizing the blood products. At the tissue level, PRP causes myoblast proliferation while PPP has led to myoblast induction, potentially identifying improved native muscle healing. Conflicting studies have been identified for the use of PRP for muscle injury. A growing body of positive results for PPP was identified, but high-quality comparative studies are needed.

Anti-oxidative and anti-inflammatory effects of Ginkgo biloba extract (EGb761) on hindlimb skeletal muscle ischemia-reperfusion injury in rats.

In posterior spine surgery, retractors exert pressure on paraspinal muscles, elevating intramuscular pressure and compromising blood flow, potentially causing muscle injury during ischemia-reperfusion. Ginkgo biloba extract (EGb 761), known for its antioxidant and free radical scavenging properties and its role in treating cerebrovascular diseases, is investigated for its protective effects against muscle ischemia-reperfusion injury invitro and invivo. Animals were randomly divided into the control group, receiving normal saline, and experimental groups, receiving varying doses of EGb761 (25/50/100/200 mg/kg). A 2-h hind limb tourniquet-induced ischemia was followed by reperfusion. Blood samples collected pre-ischemia and 24 h post-reperfusion, along with muscle tissue samples after 24 h, demonstrated that EGb761 at 1000 μg/mL effectively inhibited IL-6 and TNF-α secretion in RAW 264.7 cells without cytotoxicity. EGb761 significantly reduced nitric oxide (NO) and malondialdehyde (MDA) levels, myeloperoxidase (MPO) activity, and increased glutathione (GSH) levels compared to the control after 24 h. Muscle tissue sections revealed more severe damage in the control group, indicating EGb761's potential in mitigating inflammatory responses and oxidative stress during ischemia-reperfusion injury, effectively protecting against muscle damage.

Pathomechanics of lumbrical and flexor digitorum profundus muscle tears in climbers: A cadaveric model

Lumbrical muscles originate on the flexor digitorum profundus (FDP) tendons and, during fist making, they move in the same direction when FDP muscle produces maximal proximal tendon gliding. Injuries of the bipennate lumbricals have been described when a shear force acts between the origins on adjacent tendons of the FDP, as they glide in opposite directions in asymmetric hand postures. Other structures of the deep flexors complex can be affected during this injury mechanism, due to the so-called quadriga effect, which can commonly occur during sport climbing practise. Biomechanical studies are needed to better understand the pathomechanism. A cadaveric study was designed to analyse the effects of load during the fourth lumbrical muscle injury mechanism. The amount of FDP tendon gliding and metacarpophalangeal (MCP) joint flexion of the 5th finger were calculated. Ten fresh-frozen cadaveric specimens (ten non-paired forearms and hands) were used. The specimens were placed on a custom-made loading apparatus. The FDP of the 5th finger was loaded, inducing isolated flexion of the 5th finger, until rupture. The rupture occurred in all specimens, under a load of 11 kg (SD 4.94), at 9.23 mm of proximal tendon gliding (SD 3.55) and at 21.4° (SD 28.91) of MCP joint flexion. Lumbrical muscle detachment from the 4th FDP was observed, from distal to proximal, and changes in FDP tendons at the distal forearm level too. The quadriga effect can lead to injury of the bipennate lumbrical muscles and the deep flexors complex in the hand and forearm.

Curcumin and its nano-formulations combined with exercise: From molecular mechanisms to clinic.

Curcumin is a strong substance derived from turmeric, a popular spice, renowned for its antioxidant and anti-inflammatory abilities. The study delved deeply into a thorough examination of various sources to evaluate the impact of both regular curcumin and nano-formulated curcumin on elements that impact physical performance, including muscular strain, discomfort, swelling, and oxidative tension. While engaging in exercise, the body experiences a rise in reactive oxygen species and inflammation. As a result, it is important to ensure a proper balance between internal and external sources of antioxidants to maintain stability in the skeletal muscle. Without this balance, there is a risk of muscle soreness, damage, and ultimately, a decline in exercise performance. Curcumin possesses the ability to enhance physical performance and reduce the symptoms of muscle fatigue and injury by virtue of its antioxidative and anti-inflammatory properties. Including curcumin supplements appears to have advantageous effects on various aspects of exercise, such as enhancing performance, assisting with recovery, lessening muscle damage and discomfort, and lowering levels of inflammation and oxidative stress. However, a thorough assessment is necessary to precisely gauge the healing advantages of curcumin in enhancing exercise ability and reducing recovery time.

Process mining to investigate the relationship between clinical antecedents and injury risk, severity and return to play in professional sports

ObjectiveThis paper presents an exploratory case study focusing on the applicability and value of process mining in a professional sports healthcare setting. We explore whether process mining can be retrospectively...

Acute and Chronic Effects of Static Stretching on Intramuscular Hamstring Stiffness.

Passive hamstring stiffness varies proximo-distally, resulting in inhomogeneous tissue strain during stretching that may affect localized adaptations and risk of muscle injuries. The purpose of the present study was to determine the acute and chronic effects of static stretching (SS) on intramuscular hamstring stiffness. Thirty healthy active participants had acute changes in passive biceps femoris (BF), semimembranosus (SM), and semitendinosus (ST) stiffness measured at 25% (proximal), 50% (middle), and 75% (distal) muscle length, using shear-wave elastography, immediately after SS. Participants then completed 4 weeks of either a SS intervention (n = 15) or no intervention (CON, n = 15) with stiffness measured before and after the interventions. The acute and chronic effects of SS were compared between anatomical regions and between regions on the basis of their relative stiffness pre-intervention. Acutely, SS decreased stiffness throughout the BF and SM (p ≤ 0.05) but not the ST (p = 0.326). However, a regional effect of stretching was observed for SM and ST with greater reduction in stiffness occurring in stiffer muscular regions (p = 0.001-0.013). Chronically, SS increased BF and ST (p < 0.05), but not SM (p = 0.422) stiffness compared with CON, but no regional effect of stretching was observed in any muscle (p = 0.361-0.833). SS resulted in contrasting acute and chronic effects, acutely decreasing stiffness in stiffer regions while chronically increasing stiffness. These results indicate that the acute effects of SS vary along the muscle's length on the basis of the relative stiffness of the muscle and that acute changes in stiffness from SS are unrelated to chronic adaptations.

Technique of Distal Tendon Excision for the Treatment of Chronic Pain Caused by Isolated Proximal Gracilis Tears

Proximal gracilis tear is a rare sports-related injury that can easily lead to misdiagnosis and underdiagnosis. Clinical manifestations are dominated by localized pain, tenderness, and dysfunction. Here, we report a therapy of proximal segmental tear of the gracilis and demonstrate its treatment process and clinical outcome. This Technical Note describes in detail the minimally invasive distal gracilis resection technique for the treatment of chronic proximal gracilis ruptures, focusing on the most important technical aspects and thus attempting to introduce this procedure and make it more widely used in the treatment of similar muscle injuries.

Benzoylaconine Protects Skeletal Muscle Against Ischemia-Reperfusion Injury Through Activation of IF1-Dependent AMPK/Nrf2 Axis.

Aconitum carmichaelii (Fuzi) has been conventionally used to cure a variety of ailments, such as pain, cold sensations, and numbness of limb muscles (Bi Zheng) in China. Our prior investigations identified Benzoylaconine (BAC) as a bioactive alkaloid derived from Aconitum carmichaelii, with other studies also demonstrating its significant pharmacological potential. This study aimed to explore the potential of BAC as a protective agent against skeletal muscle ischemia-reperfusion (I/R) injury and to elucidate the underlying mechanisms. In vivo models involved subjecting Sprague-Dawley rats to I/R through femoral artery ligation followed by reperfusion, while in vitro models utilized C2C12 cells subjected to hypoxia/reoxygenation (H/R). CCK-8 assay was used to assess cell viability. TUNEL staining and flow cytometric analysis were used to measure cell apoptosis. Biochemical assay was used to assess skeletal muscle injury and oxidative stress. Immunofluorescence and Western blot were performed to determine protein levels. BAC effectively protected muscle tissue from I/R injury, enhancing cell viability (p<0.01), elevating SOD levels (p<0.05), and reducing CK (p<0.01), LDH (p<0.01), ROS (p<0.01), MDA (p<0.01), and apoptosis-related molecules in vivo and in vitro (p<0.05, p<0.01). Mechanistically, BAC increased the expression of IF1, phosphorylated AMPK, facilitated the translocation of nuclear Nrf2, and induced the expression of HO-1 (p<0.01). Notably, AMPK inhibitor Compound C significantly hindered the ability of BAC to ameliorate H/R-induced cell injury (p<0.05), oxidative stress(p<0.01), and apoptosis (p<0.05), as well as promote Nrf2 nuclear translocation (p<0.01). Moreover, silencing of IF1 with siRNA abolished BAC-induced activation of AMPK/Nrf2 axis (p<0.01). Our study provides novel evidence supporting the potential of BAC as a myocyte-protective agent against I/R injury, and we establish a previously unknown mechanism involving the activation of the IF1-dependent AMPK/Nrf2 axis in mediating the protective effects of BAC.

Time-loss injuries and illnesses at the FIFA world cup Qatar 2022

ABSTRACT The study aimed to analyse incidence and characteristics of time-loss injuries and illnesses during the FIFA World Cup Qatar 2022. Of 838 male football players, 705 consented to participate. Team medical staff reported 82 time-loss injuries, corresponding to an injury event incidence of 5.6 injuries/1000 h of total exposure (95%CI 4.5 to 7.0 injuries/1000 h), with a median of 2 time-loss injury events per team (IQR, 1 to 4.5, range 0–7). The total injury burden was 103 (95% CI 61 to 152) days per 1000 h. Muscle/tendon injuries had the highest incidence of tissue types (48 cases, 3.3/1000 h (95% CI 2.5 to 4.4), and hamstring muscle injuries were the most frequent diagnosis (16 cases, incidence 1.1/1000 h, 95% CI 0.6 to 1.8). Match injury event incidence was 20.6/1000 h (15.0 to 27.7) and training injury event incidence was 2.1/1000 h (1.4 to 3.1). The majority (52%) of sudden-onset injuries were non-contact injuries, 40% direct contact and 8% indirect contact. We recorded 15 time-loss illnesses, corresponding to an illness event incidence of 1.1 per 1000 competition days, (95% CI: 0.6 to 1.8), and illness burden of 2.1 (1.0 to 3.4) days lost per 1000 competition days. The most common illness was respiratory infection (12 cases, 80%). Match injury event incidence was the lowest in any FIFA World Cup since injuries have been monitored.

Self-powered porous polymer sensors with high sensitivity for machine learning-assisted motion and rehabilitation monitoring

Muscle contraction and relaxation inherently contains valuable information crucial for monitoring physical states, rehabilitation, and injury prevention. However, the majority of flexible wearable devices struggle to offer customizable sensors with high sensitivity, durability, and stability, resulting in suboptimal biofeedback performance. Herein, the machine learning-assisted smart motion and rehabilitation monitoring system (SMRMS) is demonstrated for full-body motion recognition and rehabilitation assessment using a designed porous triboelectric nanogenerator (TENG) array. A theoretical model of porous materials is built to demonstrate the effect mechanism of porosity on TENG output. Through pore design on the tribolayer, theoretical simulation and experimental are performed to determine the key features of porous TENG sensors with high sensitivity (1.76 kPa−1), fast response time (50 ms) and high durability (over 100,000 cycles). A ring-shaped TENG (RS-TENG) is fabricated based on the porous TENG sensor, enabling real-time recording of leg/arm force without additional attachment. By integrating the RS-TENG array with a multichannel signal acquisition system, an SMRMS is designed to capture motion information during human subjects’ exercise and rehabilitation training. These data are then fused for machine learning analytics, resulting in significantly improved accuracy in motion pattern recognition (98.75 %) and rehabilitation monitoring (100 %). The simple, precise and durable porous sensors could help mitigate the risk of excessive exercise-induced muscle injuries, expanding self-powered wearable functionalities and adaptabilities.

Atrial fibrillation induced by carbon monoxide poisoning: Case report

Background: Carbon monoxide (CO) poisoning is known to have direct toxic effects on the cardiovascular system, including the potential to cause arrhythmias by prolonging the QTc interval. The arrhythmogenic properties of CO are believed to be attributed to its impact on cardiac membranes. Case Presentation: This case report presents the clinical course and management of a 21-year-old male who presented to the Emergency Department (ED) with an altered level of consciousness following exposure to carbon monoxide while cooking on a gas cylinder in a closed room. The patient had no history of chronic medical illness and was a non-smoker. Physical examination revealed stable vital signs, clear breath sounds, and a lax, soft, and non-tender abdomen. Laboratory investigations showed elevated troponin levels indicative of cardiac muscle injury but normal potassium levels. ECG revealed atrial fibrillation with a fast ventricular rate and transient ST elevation. The patient received high flow oxygen. The carboxyhemoglobin level decreased significantly after high-flow oxygen administration, confirming the successful treatment of carbon monoxide poisoning. Echocardiography and coronary angiography demonstrated normal cardiac function and ruled out coronary artery disease, respectively. The patient received high-flow oxygen therapy, continuous cardiac monitoring, and supportive care during hospitalization. Following stabilization and restoration of sinus rhythm, the patient was discharged in stable condition. Conclusion: This case highlights the importance of prompt recognition and management of carbon monoxide poisoning, as well as the need for careful evaluation of cardiac function in such cases. The patient responded well to high-flow oxygen therapy, leading to a decrease in the carboxy hemoglobin level and resolution of symptoms. Timely recognition and appropriate management of carbon monoxide poisoning are crucial in preventing adverse cardiac events and ensuring a favorable outcome for the patient.

An ALK2 inhibitor, BLU-782, prevents heterotopic ossification in a mouse model of fibrodysplasia ossificans progressiva.

Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disease driven by gain-of-function variants in activin receptor-like kinase 2 (ALK2), the most common variant being ALK2R206H. In FOP, ALK2 variants display increased and dysregulated signaling through the bone morphogenetic protein (BMP) pathway resulting in progressive and permanent replacement of skeletal muscle and connective tissues with heterotopic bone, ultimately leading to severe debilitation and premature death. Here, we describe the discovery of BLU-782 (IPN60130), a small-molecule ALK2R206H inhibitor developed for the treatment of FOP. A small-molecule library was screened in a biochemical ALK2 binding assay to identify potent ALK2 binding compounds. Iterative rounds of structure-guided drug design were used to optimize compounds for ALK2R206H binding, ALK2 selectivity, and other desirable pharmacokinetic properties. BLU-782 preferentially bound to ALK2R206H with high affinity, inhibiting signaling from ALK2R206H and other rare FOP variants in cells in vitro without affecting signaling of closely related homologs ALK1, ALK3, and ALK6. In vivo efficacy of BLU-782 was demonstrated using a conditional knock-in ALK2R206H mouse model, where prophylactic oral dosing reduced edema and prevented cartilage and heterotopic ossification (HO) in both muscle and bone injury models. BLU-782 treatment preserved the normal muscle-healing response in ALK2R206H mice. Delayed dosing revealed a short 2-day window after injury when BLU-782 treatment prevented HO in ALK2R206H mice, but dosing delays of 4 days or longer abrogated HO prevention. Together, these data suggest that BLU-782 may be a candidate for prevention of HO in FOP.

Presence of Additional Pathology in Low-Grade Acromioclavicular Joint Injuries.

To determine if additional pathology is present in low-grade acromioclavicular (AC) joint injuries. Prospective case series. Patients were assessed by primary care sports medicine physicians at a single institution between 2019 and 2023. Patients aged 18 to 65 years diagnosed with a type I to III AC injury based on clinical and radiographic evaluation. Consenting patients underwent magnetic resonance imaging (MRI) evaluation within 21 days of injury. All injuries were treated nonoperatively. Additional pathologies identified on MRI were reported in a standardized fashion by fellowship-trained musculoskeletal radiologists. Twenty-nine patients (26 men/3 women) were consented with a mean (±SD) age of 28.6 ± 9.5 years. The mean time from injury to MRI was 8.1 ± 5.9 days. Twenty-three injuries were sport related, and 6 were accidental traumas. Based on MRI, injury type was reclassified in 16 of 29 patients, and 13 remained unchanged. Additional pathologies identified included 14 muscle injuries, 5 rotator cuff tears, 5 labral tears, 1 nondisplaced fracture, and 1 intra-articular body. MRI evidence suggests that most AC joint injuries are more severe than clinically diagnosed. Identifying additional pathology may alter diagnostic and treatment guidelines for type I to III AC joint injuries.

Lipidomics and single-cell RNA sequencing reveal lipid and cell dynamics of porcine glycerol-injured skeletal muscle regeneration model

AimsIntramuscular fat (IMF) infiltration and extracellular matrix (ECM) deposition are characteristic features of muscle dysfunction, such as muscular dystrophy and severe muscle injuries. However, the underlying mechanisms of cellular origin, adipocyte formation and fibrosis in skeletal muscle are still unclear. Main methodsPigs were injected with 50 % glycerol (GLY) to induce skeletal muscle injury and regeneration. The acyl chain composition was analyzed by lipidomics, and the cell atlas and molecular signatures were revealed via single-cell RNA sequencing (scRNA-seq). Adipogenesis analysis was performed on fibroblast/fibro-adipogenic progenitors (FAPs) isolated from pigs. Key findingsThe porcine GLY-injured skeletal muscle regeneration model was characterized by IMF infiltration and ECM deposition. Skeletal muscle stem cells (MuSCs) and FAP clusters were analyzed to explore the potential mechanisms of adipogenesis and fibrosis, and it was found that the TGF-β signaling pathway might be a key switch that regulates differentiation. Consistently, activation of the TGF-β signaling pathway increased SMAD2/3 phosphorylation and inhibited adipogenesis in FAPs, while inhibition of the TGF-β signaling pathway increased the expression of PPARγ and promoted adipogenesis. SignificanceGLY-induced muscle injury and regeneration provides comprehensive insights for the development of therapies for human skeletal muscle dysfunction and fatty infiltration-related diseases in which the TGF-β/SMAD signaling pathway might play a primary regulatory role.

Muscle Injuries in Elite Youth Football Academy: A Six-Year Longitudinal Study on the U15 Football Team

To develop specific preventive strategies, it is necessary to investigate in detail the occurrence of injuries in young football players. This study aimed to provide details about the type, location, severity, and contact nature of muscle injuries in elite U15 Croatian football players. A total number of 130 muscle injuries occurred during the six competitive seasons, of which 88 were DOMS injuries and 42 were rupture injuries. Specifically, 87% of all muscle injuries belonged to the four major groups, with only 15 injuries to the other muscle groups: hamstrings (43), quadriceps (41), adductors (25), calves (6). The muscle injury incidence was stable during the observed period as the injury incidence rate ratio (IRR) was 1.01 (95%CI: 0.99–1.03), with 3.13 (95%CI: 3.09–3.17) muscle injuries per 1000 h of exposure in the first season and 3.06 (95%CI: 3.02–3.1) in the sixth season. A significantly higher risk for muscle injuries was discovered in the competition as the incidence for the whole observed period was 7.38 (95%CI: 7.29–7.47) compared to 2.25 (95%CI: 2.24–2.26) in the training period. Despite the relatively stable number of sustained muscle injuries, the relative proportion of muscular injuries increased over the years due to a severe decrease in the total number of injuries. Regarding the proportion of players who had sustained a muscle injury, our results suggest that approximately two out of five players can expect a muscular injury over the one-season period. Relatively high injury expectancy rates, as well as reinjury rates, require specific preventive interventions that will reduce the number and severity of new and recurred injuries. Future studies should include a wide set of predictor variables in order to establish the most important injury risk factors.

Ultrasound in sports traumatology

Ultrasound (US) has numerous applications in sports traumatology. The technical progress of mobile US devices has led to increasing use of ultrasound as a primary diagnostic tool. New applications such as elastography and 3 D vascularization are used for special indications.The purpose of this review is to present the current status of ultrasound in the diagnosis of sports injuries and sport traumatology including established applications and new technical advances. US is presented both in its comparison to other imaging modalities and as a sole diagnostic tool.US can be used for initial diagnosis to improve the clinical examination and for intensive shortterm follow-up imaging. The main areas of application are currently the diagnosis of acute muscle and tendon injuries as well as overuse injuries. In particular, the exclusion of structural muscle injuries can be adequately ensured with US in the majority of anatomical regions. The recently published guideline on fracture ultrasound has strengthened the clinical evidence in this area, especially in comparison to conventional radiography and in the development of algorithms and standards. The increasing use of mobile ultrasound equipment with adequate image quality makes US a location-independent modality that can also be used at training sites or during road games.