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Ultrasound contrast agents are clinically used for diagnosis of internal organs, but ultrasound contrast agents are rarely applied clinically in musculoskeletal disorders. Our study aims to comparatively analyze the differences between ultrasonographic images through peri-injury injection of the clinically used microbubble and researched nanoparticle contrast agents in various muscular injury models. To compare contrast-enhanced images in different muscle injury models, we prepared groups of rats with sham, laceration, punch, contusion, and toxin injection injuries. We measured H2O2 levels using the Amplex Red assay by extracting tissue from the damaged area. As comparative contrast agents, SonoVue®, a commercially available microbubble contrast agent, and poly(vanillinoxalte) (PVO) nanoparticles, which are H2O2-responsive nanoparticles, were used. The difference in contrast between the two contrast agents was recorded as an ultrasound movie, and J-image software 1.53p was used to quantify and analyze the maximum and minimum echogenicity values of the images after contrast enhancement. In the Amplex red assay for the highest H2O2 level in each muscle injury model, the maximum level showed 24 h after the modeling. In the sham rats, PVO injection showed no increased echogenicity except at the needle insertion site, but SonoVue® injection showed increased echo signal throughout the injected muscle immediately after injection. One day after the preparation of the lesion, PVO and SonoVue® were injected into the lesion site and ultrasound was performed on the lesion site. After the injection of PVO nanoparticles, contrast enhancement was observed at the lesion site immediately. SonoVue® injections, on the other hand, showed a widespread pattern of echo signals and an increase in echo retention only at the lesion site over time, but this was not clear. There were statistically significant differences between the highest and lowest echogenicity in PVO and SonoVue® contrast-enhanced images in all models. Contrast enhancement lasted more than 3 h in the PVO injection, but disappeared within 3 h in the SonoVue® injection. PVO nanoparticles showed the possibility of physiologic contrast by CO2 generated by conjugation with H2O2 generated by muscle injuries, and SonoVue® injection observed the possibility of microbubble contrast as a contrast agent with a pooling effect that lasts longer on the lesion. Further research is needed to investigate the use of various ultrasound contrast agents, including nanoparticles, in musculoskeletal disorders, as well as the potential for further utilities of microbubble contrast agents. [ABSTRACT FROM AUTHOR]

The prescription of maximal dynamic strength training in both adults and children is based on the evaluation of maximum strength, usually by one-repetition maximum tests (1RM). This study examined the test-retest reliability and the minimal detectable change (MDC) of the maximal force test and muscle power test. Forty-eight children (9–14 years old) completed two test–retest sessions that involved a one-repetition maximum (1RM) test and a muscle power test for leg extension (LE) and seated bench press (SBP). The MDC values of the 1RM test in the LE and SBP tests ranged from 7.35 to 11.34 kg and 6.84 to 7.92 kg, respectively. The MDC values of the muscle power test in the LE and SBP ranged from 30.32 to 63.20 Watt and 22.65 to 29.53 Watt, respectively. In children 9 to 14 years old, the increase of maximum strength along the growth curve was different in each muscle group studied. The repeatability of the 1RM test of the SBP was excellent (ICC 0.974) and was better than that of the LE (ICC, 0.954). The MDC of the 1RM test evaluation was 19.56% in the LE and 12.93% in the SBP. [ABSTRACT FROM AUTHOR]

Ultrasound is clinically used for diagnosis and interventions for musculoskeletal injuries like muscle contusion, but contrast of ultrasonography still remains a challenge in the field of the musculoskeletal system. A level of hydrogen peroxide (H2O2) is known to be elevated during mechanical tissue damage and therefore H2O2 can be exploited as a diagnostic and therapeutic marker for mechanical injuries in the musculoskeletal system. We previously developed poly(vanillin-oxalate) (PVO) as an inflammation-responsive polymeric prodrug of vanillin, which is designed to rapidly respond to H2O2 and exert antioxidant and anti-inflammatory activities. The primary aim of this study is to verify whether PVO nanoparticles could serve as contrast agents as well as therapeutic agents for musculoskeletal injuries simultaneously. In a rat model of contusion-induced muscle injury, PVO nanoparticles generated CO2 bubbles to enhance the ultrasound contrast in the injury site. A single intramuscular injection of PVO nanoparticles also suppressed contusion-induced muscle damages by inhibiting the expression of pro-inflammatory cytokines and inflammatory cell infiltration. We, therefore, anticipate that PVO nanoparticles have great translational potential as not only ultrasound imaging agents but also therapeutic agents for the musculoskeletal disorders such as contusion. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) is a complex condition characterized by a multifaceted pathophysiology. It presents significant diagnostic and prognostic challenges in clinical settings. This narrative review explores the evolving role of biofluid biomarkers as essential tools in the diagnosis, prognosis, and treatment of TBI. In recent times, preclinical and clinical trials utilizing these biofluid biomarkers have been actively pursued internationally. Among the biomarkers for nerve tissue proteins are neuronal biomarkers like neuronal specific enolase and ubiquitin C-terminal hydrolase L1; astroglia injury biomarkers such as S100B and glial fibrillary acidic protein; axonal injury and demyelination biomarkers, including neurofilaments and myelin basic protein; new axonal injury and neurodegeneration biomarkers like total tau and phosphorylated tau; and others such as spectrin breakdown products and microtubule-associated protein 2. The interpretation of these biomarkers can be influenced by various factors, including secretion from organs other than the injury site and systemic conditions. This review highlights the potential of these biomarkers to transform TBI management and emphasizes the need for continued research to validate their efficacy, refine testing platforms, and ultimately improve patient care and outcomes., Competing Interests: Conflict of Interest: The authors have no potential conflicts of interest to disclose., (Copyright © 2024. Korean Society for Neurorehabilitation.)

Aim: To compare preoperative and intraoperative electrophysiologic values in patients who underwent brain and spine surgeries., Material and Methods: A retrospective medical record review was conducted on patients who underwent brain and spine surgery between January 2014 and July 2018. Patients underwent preoperative electrophysiologic monitoring within a week before the operation and intraoperative monitoring during the surgery. Monitoring parameters included the onset latency (msec) and amplitude (mV) of motor evoked potential (MEP), somatosensory evoked potential (SEP), electroneuronography, and brainstem auditory evoked potential (BAEP)., Results: The latency of the MEP and SEP were significantly prolonged while the amplitude was decreased during operation. Specifically, patients with abnormal findings in their preoperative assessments showed more prominent differences compared to those with normal findings. However, there was no significant difference between preoperative and intraoperative results based on which side of the hemisphere was affected or unaffected. Unlike the MEP and SEP parameters, there were no significant changes in the facial electroneuronography and BAEP parameters., Conclusion: There were differences in the preoperative and intraoperative monitoring parameters. Further studies are necessary to understand the underlying mechanisms behind these changes during surgery.