Median Nerve Research Articles

Artificial intelligence models using F-wave responses predict amyotrophic lateral sclerosis

Abstract Nerve conduction F-wave studies contain critical information about subclinical motor dysfunction which may be used to diagnose patients with amyotrophic lateral sclerosis (ALS). However, F-wave responses are highly variable in morphology, making waveform interpretation challenging. Artificial Intelligence techniques can extract time-frequency features to provide new insights into ALS diagnosis and prognosis. A retrospective analysis was performed on F-wave responses from 46,802 patients. Discrete wavelet transforms were applied to time-series waveform responses after stimulating ulnar, median, fibular, and tibial nerves. Wavelet coefficient statistics, onset age, sex, and BMI were features for training a Gradient Boosting Machine model on 40,095 (5,329 diagnosed with motor neuron disease). Model performance was tested on responses from 689 ALS patients meeting Gold Coast criteria and 689 age- and sex-matched controls. An exploratory analysis examined model performance on cohorts of patients with inclusion body myositis (IBM), cervical radiculopathy, lumbar radiculopathy, or peripheral neuropathy which can mimic ALS symptoms. Factors affecting survival were estimated through cox proportional hazards regression. The model trained using wavelet-features on the full waveform had 90% recall, 87% precision, and 88% accuracy. Similar model performance was measured using features only from the M-Wave or F-Wave. Classification probabilities for ALS patients were statistically different from the diagnoses mimicking ALS symptoms (p<0.001, ANOVA, Tukey’s post-hoc), Higher model classification probabilities of ALS, older age at onset, and family history of ALS alone or with frontotemporal dementia were factors decreasing survival. Longer diagnostic delay and upper limb onset site were factors increasing survival. Model scores two standard deviations below the mean had 4 months increased survival (two standard deviations below had 3 months decreased survival). Artificial intelligence techniques extracted important information from F-wave responses to estimate a patient’s likelihood of ALS and their survival risks. Although the model can make predictions at specific decision threshold as presented here, the true strength of such a model lies in its ability to provide probabilities about whether a patient is likely to have ALS compared to other mimicking diagnoses such as IBM, cervical or lumbar radiculopathy, or peripheral neuropathy. These probabilities provide clinicians with additional information they can use to make the final diagnosis with greater confidence and precision. Integrating such a model into the clinical workflow could help clinicians diagnose ALS sooner and manage treatment based on estimated survival, which may improve outcomes and patients’ quality of life.

Research Progress in the Carpal Tunnel Syndrome (CTS)

Carpal tunnel syndrome (CTS) is a common condition that causes pain, numbness, and weakness in the hand due to a pinched median nerve in the wrist. A higher percentage of women than men have carpal tunnel syndrome, which affects about 3.8% of the population. The diagnosis procedure includes the patient's medical history, physical examination, and electrodiagnostic testing, all of which are essential for assessing the nervous system's function and severity. Based on these assessments, CTS is classified as mild, moderate, or severe. Conservative treatment, including corticosteroids, wrist splints, and a range of physical therapy, is usually recommended for mild to moderate cases, while surgical treatment is reserved for severe cases. Endoscopic carpal tunnel release (ECTR) and open carpal tunnel release (OCTR) are surgical options. The purpose of this article is to explore risk factors, diagnostic approaches, and treatment approaches in order to provide better individualized care in clinical practice, and to make recommendations for future treatment improvements and research.

Gender Differences in Nerve Conduction Parameters of Upper Limb Nerves in Healthy Adults: A Comparative Study

ABSTRACT Background: Nerve conduction studies (NCSs) are essential diagnostic tools for evaluating peripheral nerve function. The influence of gender on nerve conduction parameters, such as conduction velocity, latency, and amplitude, remains a topic of interest. Previous studies have suggested gender differences in nerve conduction but have not provided definitive conclusions. Objective: This study aims to compare the nerve conduction parameters of the upper limb nerves (median, ulnar, and radial) in healthy male and female adults. Material and Methods: A total of 100 healthy adults (50 males and 50 females) were selected for this study. NCSs were performed on the median, ulnar, and radial nerves, measuring parameters including conduction velocity, latency, and amplitude. Results: The male group exhibited significantly faster conduction velocities, shorter latencies, and higher amplitudes compared to the female group. The median nerve showed the most pronounced gender differences in conduction velocity. Conclusion: Gender differences in nerve conduction parameters were evident, with males showing faster conduction and higher amplitude. These differences should be considered in clinical practice to improve the accuracy of NCSs and diagnosis.

Ultrasound-guided needle knife release with different pathways for carpal tunnel syndrome: a randomized controlled trial

To evaluate the clinical efficacy of ultrasound-guided needle knife release with different pathways for carpal tunnel syndrome (CTS). Sixty CTS patients were randomly divided into a transverse group and a longitudinal group, with 30 patients in each group. The transverse group received the needle knife release under ultrasound above and below the median nerve along the short axis, while the longitudinal group received the needle knife release under ultrasound above the median nerve along the long axis. The patients' visual analogue scale (VAS) scores, Levine scores, and median nerve cross-section area (CSA) were assessed before treatment, on the 7th, 14th, and 30th days after treatment. The median nerve conduction indexes (motor conduction: latency [Lat], amplitude[Amp], motor conduction velocity [MCV]; sensory conduction: Lat, Amp, sensory conduction velocity [SCV]) were evaluated before treatment and on the 30th day after treatment. Compared before treatment, the VAS scores, Levine scores, and median nerve CSA were reduced in both groups on the 7th, 14th, and 30th days after treatment (P<0.05); the transverse group showed lower VAS and Levine scores and smaller CSA than those in the longitudinal group (P<0.05). On the 30th day after treatment, motor and sensory Lat was reduced (P<0.05), motor and sensory Amp was increased (P<0.05), and MCV and SCV were faster (P<0.05) in both groups. The transverse group had shorter Lat, higher Amp, and faster MCV and SCV than those in the longitudinal group (P<0.05). The ultrasound-guided needle knife release with transverse and longitudinal pathways could both effectively alleviate pain and improve median nerve conduction in CTS patients, with the transverse pathway showing superior efficacy to longitudinal pathway.

Nerve transfer of the median flexor pollicis brevis branch to the deep branch of the ulnar nerve for ulnar nerve palsy: a cadaveric feasibility study.

An ulnar nerve (UN) palsy is devastating for hand function, resulting in an intrinsic minus position or claw hand with a loss of pinch grip. Distal nerve transfers facilitate faster reinnervation of hand intrinsic muscles in cases of proximal ulnar nerve lesions. The traditional anterior interosseous nerve (AIN) to UN motor transfer is commonly used, however, this still leads to long reinnervation times for the distal intrinsic muscles, important for the thumb to index pinch grip. This study investigated the feasibility of a more distal nerve transfer, from the median thenar to the deep branch of the UN (DBUN), in six cadaveric hands. A separate branch of the median nerve to the superficial head of flexor pollicis brevis (sFPB) arose distally of the thenar branch from the common digital nerve of the thumb shortly before the bifurcation of the ulnar palmar digital nerve to the thumb in all specimens, with a mean distance to the thenar branch of 8.3 ± 5.3 mm. The sFPB motor branch had a mean length of 11.5 ± 1.5 mm. The mean distance between the division of the dorsal cutaneous branch of the UN, where the AIN to UN motor transfer is usually performed, and the transfer between the sFPB branch to the DBUN was 132 ± 11 mm. A distal nerve transfer between the median innervated motor branch to the sFPB to the DBUN shortens the reinnervation distance for the first dorsal interosseous, the adductor pollicis, and the deep head of the FPB muscles, which is a prerequisite for restoration of the pinch grip.

Proximal Median Nerve Conduction Velocity Slowing in Carpal Tunnel Syndrome: An Observational Retrospective Study.

Carpal Tunnel Syndrome (CTS) is the most common entrapment neuropathy, characterised by compression of the median nerve at the wrist. Traditional understanding views CTS as a distal compression issue, but recent evidence suggests potential proximal involvement. This study aimed to assess the prevalence of proximal median nerve conduction velocity (CV) slowing in CTS patients and examine its association with CTS severity. In this retrospective observational study, data were analysed from 80 CTS patients and 40 controls from the Electrophysiology Lab at a tertiary care institute. Nerve conduction studies (NCS) evaluated the median nerve's conduction velocity and latency. Patients were classified by CTS severity, and nerve conduction parameters were statistically compared between groups. CTS patients exhibited significantly prolonged distal motor latency (DML) (5.2 ± 0.8 ms) and reduced forearm motor conduction velocity (MCV) (55.3 ± 4.1 m/s) compared to controls (P < .01). Approximately 27.45% of CTS hands showed proximal median nerve slowing. The severity classification showed that Grade 3 CTS was the most prevalent (47%), followed by Grade 2 (23%) and Grade 1 (10%). There was a negative correlation between distal latency and forearm conduction velocity, suggesting that as distal latency increases, forearm conduction velocity decreases. Post-operatively, significant improvements were observed in distal latency (mean decrease: 1.2 ± 0.5 ms, P < .01), but median nerve conduction velocity remained unchanged. While there was a trend towards improvement in CMAP amplitude, the difference did not reach statistical significance. A subset of CTS cases exhibits reduced proximal median nerve conduction velocity, which correlates with CTS severity. This suggests retrograde degeneration may contribute to CTS pathology, challenging the traditional view of CTS as a purely distal compression disorder.

Accuracy of a Superficial Landmark of the Recurrent Branch of the Median Nerve and Anatomical Features of Transverse Muscle Fibres Observed During Carpal Tunnel Release.

Background: Surgeons use anatomical landmarks like the scaphoid tubercle, pisiform, trapezial tubercle and hook of hamate, along with Kaplan cardinal line (KCL) to avoid injury to the recurrent motor branch (RMB) of the median nerve during carpal tunnel release. The presence of transverse muscle fibres (TMF) overlying the transverse carpal ligament (TCL) may suggest proximity of the RMB, but their anatomical relationship is unclear. In this study, we evaluated the accuracy of anatomical landmarks to the RMB, TMF origin and insertion, and examined the relationship between TMF presence and RMB running patterns. Methods: We dissected 30 hands from 16 fresh-frozen cadavers. After marking the superficial landmarks, we made a skin incision to confirm the presence of TMF and examined their origins and insertions. We then opened the carpal tunnel, dissected the RMB and recorded each position on a coordinate system using a fluoroscopic imaging system. Results: TMF were observed in 18 hands (60%): 13 were continuous with the abductor pollicis brevis (APB), 2 were continuous with the superficial head of the flexor pollicis brevis (FPB) and 3 were continuous with both. The bifurcation point of the RMB was significantly located 4.5 mm ulnar and 7.5 mm proximal to the superficial landmark at the median. The RMB was classified according to Poisel classification: 24 (80%) were of the extraligamentous type, 4 (13%) of the transligamentous type, 1 (3%) of the preligamentous type and 1 (3%) of the subligamentous type. Amongst these, the transligamentous/preligamentous/subligamentous types are at high risk for RMB injury during TCL incision. No significant association existed between TMF presence and these high-risk RMB types.. Conclusions: The actual RMB may be located ulnar and proximal to the superficial landmark, indicating that surgeons should be cautious about RMB damage even in the absence of TMF.

Hydrogel-Based Innovations in Carpal Tunnel Syndrome: Bridging Pathophysiological Complexities and Translational Therapeutic Gaps

Carpal Tunnel Syndrome (CTS) is a prevalent neuropathic disorder caused by chronic compression of the median nerve, leading to sensory and motor impairments. Conventional treatments, such as corticosteroid injections, wrist splinting, and surgical decompression, often fail to provide adequate outcomes for chronic or recurrent cases, emphasizing the need for innovative therapies. Hydrogels, highly biocompatible three-dimensional biomaterials with customizable properties, hold significant potential for CTS management. Their ability to mimic the extracellular matrix facilitates localized drug delivery, anti-adhesion barrier formation, and tissue regeneration. Advances in hydrogel engineering have introduced stimuli-responsive systems tailored to the biomechanical environment of the carpal tunnel, enabling sustained therapeutic release and improved tissue integration. Despite these promising developments, hydrogel applications for CTS remain underexplored. Key challenges include the absence of CTS-specific preclinical models and the need for rigorous clinical validation. Addressing these gaps could unlock the full potential of hydrogel-based interventions, which offer minimally invasive, customizable solutions that could improve long-term outcomes and reduce recurrence rates. This review highlights hydrogels as a transformative approach to CTS therapy, advocating for continued research to address translational barriers. These innovations have the potential to redefine the treatment landscape, significantly enhancing patient care and quality of life.

Effectiveness of adjuvant leukocyte-poor platelet-rich plasma in carpal tunnel release: a randomized controlled trial.

This study assessed the effectiveness of adding leukocyte-poor platelet-rich plasma (PRP) during carpal tunnel release surgery for patients with moderate to severe carpal tunnel syndrome. In a randomized controlled trial, 70 patients were assigned to either standard carpal tunnel release (control group) or release with leukocyte-poor PRP applied to the median nerve (PRP group). Primary outcomes were measured using the Boston Carpal Tunnel Questionnaire at 3 months, and secondary outcomes included pain, strength, sensation and electrodiagnostic examinations at multiple time points. Both groups showed similar improvements in pain, function, grip and pinch strength and electrophysiological recordings. However, the PRP group had better resolution of numbness at 3 months. These findings suggest that local PRP augmentation does not provide significant additional benefits beyond those of carpal tunnel release alone, apart from some improvement in patients' perception of numbness.Level of evidence: II.

The Efficacy of Shear Wave Elastography in Evaluating Treatment Response to US-Guided Steroid Injection in Patients with Carpal Tunnel Syndrome.

This study aimed to evaluate the efficacy of ultrasound (US)-guided local steroid injection in carpal tunnel syndrome (CTS) using shear wave elastography (SWE). A total of 47 wrists from 41 patients diagnosed with mild to moderate idiopathic CTS, based on clinical and electrophysiological criteria, were enrolled between June and October 2024. All participants underwent US-guided local steroid injection. Pre- and post-injection assessments included measurement of the median nerve's cross-sectional area (CSA) and evaluation of its elasticity through shear wave velocity (m/s) and Young's modulus (kPa). Clinical outcomes were assessed before and 6 weeks after the injection using the Visual Analog Scale (VAS), the Boston Questionnaire-Symptom Severity Scale (BQ-SSS), and the Boston Questionnaire-Functional Status Scale (BQ-FSS). The clinical scores before and after the injection were compared to the corresponding US and SWE measurements. Prior to steroid injection, the median nerve CSA was 15.53±4.28mm², shear wave velocity was 4.01±0.27m/s, and Young's modulus was 49.03±6.90kPa. Six weeks following the injection, significant reductions were observed in these parameters, with CSA decreasing to 12.04±2.59mm², shear wave velocity to 3.03±0.22m/s, and Young's modulus to 28.09±4.16kPa (p<0.001 for each). Clinical scores also demonstrated significant improvement, with VAS decreasing from 7.12±1.09 to 2.91±0.86, BQ-SSS from 38.36±4.97 to 21.36±3.50, and BQ-FSS from 23.72±3.81 to 13.27±1.65 (p<0.001 for all). US-guided steroid injection improves clinical symptoms and reduces the CSA and nerve elasticity in CTS patients six weeks post-treatment.

Motor function and compound muscle action potential amplitude in children with spinal muscular atrophy treated with nusinersen.

Disease-modifying therapies can improve motor function in patients with spinal muscular atrophy (SMA), but efficacy varies between individuals. The aim was to evaluate the efficacy and safety of nusinersen treatment in children with SMA and to investigate prognostic factors. Motor function, compound muscle action potential (CMAP), and other indicators were prospectively collected before and 14months after nusinersen treatment. A total of 55 children were included in our study to assess safety. 41 patients (with at least 6months of nusinersen treatment) were included in the final efficacy analyses, with a median age at first treatment of 4.2years. After 14months of treatment with nusinersen, motor function improved, with increases in CHOP INTEND (Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders), HINE-2 (Hammersmith Infant Neurological Exam-Part 2), HFMSE (Hammersmith Functional Motor Scale-Expanded) and RULM (Revised Upper Limb Module) of 5.5 (95% CI -2.4-13.4), 0.8 (95% CI -0.2-1.9), 5.0 (95% CI 2.5-7.4) and 2.4 (95% CI 0.7-4.1) points, respectively. The CMAP amplitudes of the bilateral tibial, median and ulnar nerves increased, with greatest improvements of 0.87±1.41mV, 1.08±1.71mV and 0.59±1.01mV, respectively. Spearman correlation analysis showed that age at first treatment, disease duration, joint contractures and scoliosis were associated with treatment efficacy (r=-0.4-0.7, P<0.05). Subgroup analyses showed that the mean HFMSE and RULM scores improved in the Physical therapy group (P<0.05). Early treatment, mild bone and joint complications, and regular rehabilitation training were associated with better outcomes. The other motor-related functions, such as respiratory and bullar function, and prognostic factors should be studied in the future.

Photobiomodulation in carpal tunnel syndrome with pain, strength, and functionality analysis: a systematic review and meta-analysis.

Carpal tunnel syndrome (CTS) is characterized as a compressive neuropathy of the median nerve and has several treatments, including photobiomodulation, which can be performed with low-intensity laser therapy (LLLT) and light-emitting diodes (LEDs). To carry out a literature review on the effectiveness of low-intensity laser therapy (LLLT) in CTS. This study is characterized by being a systematic review with metaanalysis. The databases included were PubMed, Embase, Cochrane, the Physiotherapy Evidence Database (PEDro), Scopus and LILACS. Also, gray literature: Google Scholar, OpenGrey and CAPES Theses and DissertationsCatalog. The search was carried out in all databases on October 11, 2023 and updated on June 06, 2024. The risk of bias was assessed using the Cochrane tool, RoB 2, by two blinded reviewers and conflicts were resolved by consensus. The outcomes of interest were pain intensity (Visual analogue scale), strength (handgrip and pinch) and hand functionality (Boston questionnaire, Levine questionnaire, Purdue Pergboard Test). Statistical analysis was carried out using RevMan 5.4.1. Continuous results were expressed as standard mean differences (95% CI), with p-value of < 0.05 considered statistically significant. The value of the I2 statistical test was calculated to test for heterogeneity between studies. A random effects model was adopted. 13 randomized controlled trials were selected from 1.613 records. In the general bias analysis, two studies (15,4%) were considered to have some relevant problems that could interfere with the quality of the study, and three (23,1%) were identified as having a high risk of bias, eight studies (61,5%) were classified as having a low risk of bias. In the meta-analysis, it was possible to observe that there were no advantages of the laser for pain (p = 0.08), nor for handgrip strength (p = 0.11), but it did produce improvements in functionality. It is concluded that LLLT is an effective therapeutic modality in the treatment of CTS, improving functionality; however, despite the studies pointing to advantages for the modality in reducing pain and improving grip strength, the meta-analysis did not show this result. Even so, there is a need for more clinical trials are needed to standardize dosimetry, mainly because the primary studies showed clinical advantages of PBM. Open Science Framework (OSF)- https://doi.org/10.17605/OSF.IO/HQCRP .

Using Transcranial Magnetic Nerve Stimulation to Differentiate Motor and Sensory Fascicles in a Mixed Nerve: Experimental Rat Study.

Accurately matching the correct fascicles in a ruptured mixed nerve is critical for functional recovery. This study investigates the use of transcranial magnetic stimulation (TMS) to differentiate motor and sensory fascicles in a mixed nerve. In all 40 rats, the median nerve in the left upper arm was evenly split into three segments. The rats were separated into two groups. In Group A (20 rats), the segment with the highest amplitude during TMS was selected as the motor neurotizer and transferred to the musculocutaneous nerve. In Group B (20 rats), only the medial one-third segment was selected and transferred without using TMS. The results were compared using grooming tests, nerve electrophysiological studies, muscle tetanus contraction force measurements, muscle weight, and axon counts at 16 weeks. The grooming test showed that Group A performed significantly better than Group B at 12 and 16 weeks postoperatively. Tetanic muscle contraction force measurements also revealed that Group A had significantly better outcomes than Group B. However, electrophysiological testing, muscle weight, and axon counts showed no significant differences between the two groups. This study suggests that TMS can be used to distinguish motor fascicles from sensory fascicles in a mixed nerve. It is desirable to apply this technique intraoperatively to differentiate motor and sensory fascicles for appropriate nerve matching and to select the motor fascicles as a motor neurotizer for functioning free muscle innervation in human mixed nerve injury.

Radial to Median Sensory Nerve Transfers to Restore Sensate Key Pinch: A Cadaveric Assessment of Size Match and Implications for Transfer.

Loss of key-pinch sensation after median nerve injury poses significant functional detriment. Nerve transfers are utilized to improve function after nerve injury and size matching of donor and recipient nerves is important to optimize success. This anthropometric study investigates the anatomy of the superficial branch of the radial nerve (SBRN) to the thumb and index finger and explores radial to median sensory nerve transfers, a necessary but not heavily discussed facet of nerve transfers for the hand. Anatomic dissection of SBRN in 15 cadaver hands was performed to assess variability in diameter and branching patterns based on nerve location. Dissection of the index radial and thumb ulnar digital nerves was performed to assess diameter based on location and calculate ideal size match for nerve transfer. All specimen thumbs had 2 SBRN branches at the level of the metacarpal shaft and proximal phalanx; 87% had 2 index SBRN branches extending to the proximal phalanx. Index radial and ulnar SBRN branches were similar in diameter at all levels (p > 0.0167). There was a significant size mismatch between the individual SBRN branches and index digital at all measured levels (p < 0.0167). The thumb radial SBRN was significantly larger than ulnar SBRN (p = 0.006). Optimal size match for transfer involved transection of radial index SBRN 1 cm distal to the MCP joint and ulnar thumb SBRN 1 cm distal to the MCP joint. Consideration should be made for transfer of both index SBRN branches at the level of the MCP joint to improve size match. Corresponding digital nerves were transected 1 cm proximal to the level of SBRN harvest.

Investigating Neurometabolite Changes in Response to Median Nerve Stimulation.

Rhythmic median nerve stimulation (MNS) at 10Hz has been shown to cause a substantial reduction in tic frequency in individuals with Tourette syndrome. The mechanism of action is currently unknown but is hypothesized to involve entrainment of oscillations within the sensorimotor cortex. We used functional magnetic resonance spectroscopy (fMRS) to explore the dynamic effects of MNS on neurometabolite concentrations. Here, we investigated the effects of rhythmic and arrhythmic 10Hz MNS on glutamate (Glu) and GABA concentrations in the contralateral sensorimotor cortex in 15 healthy controls, using a blocked fMRS design. We used a Mescher-Garwood-semi-localized by adiabatic selective refocusing (MEGA-sLASER) sequence at 7 T. Our results show no difference in the difference-from-baseline measures between the two stimulation conditions. Looking at the effect of MNS over both conditions there is a trend for an initial increase in Glu/tCr (total creatine) followed by a decrease over time, whereas GABA/tCr decreased during each stimulation block. These results suggest that despite entrainment of oscillations during rhythmic MNS, there are no significant differences in the tonic neuromodulatory effects of rhythmic and arrhythmic stimulation. The reduction in Glu over the course of stimulation may reflect a decrease in the glutamatergic firing due to adaptation. This may make it less likely that an involuntary movement is generated during continuous stimulation.

Atypical Origin of Lateral Pectoral Nerve: A Case Report

In the present case, two Lateral Pectoral Nerves (LPN) were in the right axilla. The upper branch, superior LPN arose from the proximal part of the axilla deep to the clavicle from the anterior division of the upper trunk. This branch descends medially and enters the deep surface of the pectoralis major muscle. A larger LPN is seen originating from the distal part of the right lateral root of the median nerve at the lower part of the axilla, medial to the third part of the right axillary artery. This inferior LPN is 2 cm long, descends medially, and joins with the Medial Pectoral Nerve (MPN) forming ansa pectoralis. The branches from the ansa pierce the pectoralis minor muscle and enter the pectoralis major muscle. It supplies both the pectoral muscles. LPN fibers passing from the Lateral Cord (LC) through the lateral root of median have not been reported yet. The LPN is the main nerve of pectoralis major muscle. A thorough understanding of Pectoral Nerve (PN) anatomy is a must for surgeons practicing mastectomies, breast augmentation surgery, axillary dissection, harvesting pectoralis major muscle island flap, and dealing with trauma and fracture of the shoulder.

Real-world tafamidis experience in hereditary transthyretin amyloidosis with peripheral neuropathy in Brazil

Abstract Background Tafamidis is a kinetic stabilizer that binds to the transthyretin (TTR) gene, inhibiting its dissociation. It is the only disease-modifying treatment for hereditary TTR amyloidosis with peripheral neuropathy (ATTRv-PN) available in the National Therapeutic Form (Formulário Terapêutico Nacional, FTN, in Portuguese) of the Brazilian Unified Health System (Sistema Único de Saúde, SUS, in Portuguese). Objective To assess if the efficacy and safety of tafamidis in the Brazilian real-world experience are comparable to the results of clinical trials. Methods We retrospectively studied all patients with ATTRv-PN evaluated at our center from September 2011 to March 2022 (data cut-off) who were initiated on tafamidis and had at least 1 follow up visit 6 months after the initiation of the drug treatment. Neurologic and functional outcomes were compared from day 1 (D1) of the tafamidis treatment (baseline) to the last follow-up. Results In total, 33 patients were included, 18 (55%) of whom were female. All patients were carriers of the V30M mutation of ATTRv-PN, and 20 (61%) presented early onset (EO) ATTRv-PN. At baseline, the median age of the sample was of 40 (interquartile range [IQR]: 36–68) years, the median Neuropathy Impairment Score (NIS) was of 10 (6–24) points, and the median body mass index (BMI) was of 26 (23–28) kg/m2. The mean follow-up time was of 3.4 years. At the last follow-up, the BMI, the neurological impairment, and the level of disability slightly worsened compared with baseline, while the findings of the nerve conduction studies remained stable. These same results were observed across EO and late-onset (LO) ATTRv-PN patients. A total of 25 (75.8%) patients were considered responders, and 8 (24.2%), non-responders. Conclusion The efficacy and safety of tafamidis reported in clinical trials is expandable to the Brazilian real-world scenario in EO and late-onset (LO) ATTRv-PN.

Reference Values of Touch Sense Threshold from an Adult Brazilian Cohort

Semmes-Weinstein monofilaments have been widely used in clinical practice to evaluate touch sense in healthy subjects and in the population of risk of neuropathies as Diabetes Mellitus and leprosy patients. It is an effective and low-cost clinical tool indeed, however, it is an instrument of low sensitivity with subjective responses. In the 1980s, a procedure was proposed for the psychophysical assessment of touch sense by sine-wave electric current stimulation. This assessment was based on studies that suggested sinusoidal electric stimuli of several different frequencies would excite sensory fibers of different diameters, increasing the selectivity of the stimulation. This study aims to evaluate and describe touch sense perception threshold of a healthy Brazilian cohort using sine-wave electric stimulation. Reference values of Current Perception Threshold (CPT) were registered in upper limb nerves of 100 healthy subjects, 57 (male) and 43 (female). All subjects had the ulnar, median, and radial nerves evaluated with a sine-wave electric stimulator called NEUROSTIM® to quantify the CPT for the frequencies 1Hz, 250Hz and 3000Hz. The CPT reference values for the Ulnar Nerve varied between 484µA - 1003µA for the 3000Hz frequency, 168µA - 322µA for the 250Hz and 122µA - 571µA for the 1Hz frequency. For the Median Nerve varied between 468µA - 1321µA for the 3000Hz frequency, 168µA - 386µA for the 250Hz and 168µA - 437µA for the 1Hz frequency. For the Radial Nerve varied between 516µA - 1350µA, 144µA - 533µA and 173µA - 342µA for each frequency respectively. The NEUROSTIM evaluation protocol seems to be effective, objective, and able to be replicated for touch sense evaluation in healthy subjects. Having CPT reference values to a Brazilian adult healthy cohort can help professionals in the clinics to have a better understanding, management and treatment of diseases affecting touch sense, such as leprosy, diabetes mellitus and others.

Carpal Tunnel Syndrome Incidence In Teachers and Employees at SMP Negeri 1 Pematangsiantar

Background. Median nerve compression at the wrist (carpal tunnel syndrome) is the most common disorder affecting the median nerve and is the most common nerve compression syndrome. Problems usually arise from excessive hand use and work microtrauma. Objectives. To determine the incidence, severity, characteristics of respondents detected, and risk factors that allow for CTS. Methods. The study was an analytic-descriptive study with a cross-sectional approach. Using 70 samples of data from educators and employees at SMP Negeri 1 Pematangsiantar. Data were analyzed using univariate and bivariate analysis. Results. This study involved 70 educators and employees, 59 (84.3%) were found with the majority of respondents experiencing complaints with asymptomatic symptom severity 46 people (65.7%), mild 22 people (31.4%), and moderate 2 people (22.9%). Of the 59 respondents detected, 50 people (71.4%) had mild functional symptom status. The majority of respondents detected with CTS were female (74.6%) and were in the age range of 51-60 years (44%). Respondents detected with CTS had nutritional status type I obesity (34%). Of the 59 respondents detected with CTS, 54 people (91.5%) were educators who had a working duration of ≥8 hours a day (52.5%) and experienced complaints in the left hand (69.5%). Conclusion. Most predominantly female in the age range of 51-60 years who worked as educators with a working duration of ≥8 hours and the majority experienced complaints in the left hand. Keywords: Carpal tunnel syndrome, educators, incidence

TOPOGRAPHIC AND ANATOMICAL RELATIONS OF NERVES AND ARTERIES IN THE THENAR MUSCLES

The hand has a high functional significance, and it is important to note that today, especially during military operations, it is often subject to injuries. In addition, hand injuries are common both at work and in everyday life. The success of reconstructive operations and restoration of motor functions of the hand largely depends on the extent to which it is possible to preserve the innervation and normal blood supply of the muscles, which is crucial for further rehabilitation and return to normal functioning. Objective of the research. To establish the topographical-anatomical relationships of nerves and arteries in the thenar muscles of human fetuses. Material and methods. Clarification of the intramuscular distribution of nerves and arteries in the muscles of the thenar eminence was carried out on 32 preparations of the hand of human fetuses of 81.0-375.0 mm parietococcygeal length (PCL) using macromicroscopic preparation, injection vessels, and morphometry without external signs of anatomical deviations or congenital malformations of the skeleton, fascial-muscular and vascular-nervous structures of the upper limbs. The study was conducted in accordance with the basic bioethical provisions of the Convention of the Council of Europe on Human Rights and Biomedicine (4 April 1997), the Declaration of Helsinki of the World Medical Association on the ethical principles for scientific medical research involving human subjects (1964 - 2013). ), Order of the Ministry of Health of Ukraine No. 690 of 23.09.2009, and taking into account the Methodological Recommendations of the Ministry of Health of Ukraine "Procedure for Removal of Biological Objects from Deceased Persons Whose Bodies are Subject to Forensic and Pathological Examination for Scientific Purposes" (2018). The Commission on Biomedical Ethics of the Bukovinian State Medical University (Protocol No. 7 dated 16.05.2024) did not find any violations of moral and legal norms in the conduct of research. The research is a fragment of the planned comprehensive topic of the Department of Anatomy, Clinical Anatomy and Operative Surgery and the Department of Human Anatomy named after M.H. Turkevich Bukovinian State Medical University “Regularity of gender-age structure and topographic-anatomical transformations of organs and structures of the body at the pre-and postnatal stages of ontogenesis. Peculiarities of perinatal anatomy and embryotopography” state registration No. 0120U101571). Results. The research made it possible to establish that in human fetuses, each thenar muscle has a certain source of innervation and blood supply, a certain gate located in the thenar muscles in their proximal third. Flexor pollicis brevis in most fetuses has double innervation – from the median nerve and the deep branch of the ulnar nerve. Abductor pollicis, most often receives innervation from one source – the lateral branch of the median nerve, and very rarely has an additional source – from the superficial branch of the radial nerve. Adductor pollicis is mainly innervated by 1-2 nerve trunks from the deep branch of the ulnar nerve. In 3 cases, this muscle had an additional source of innervation in the form of a thin branch from the median nerve. Conclusion. In human fetuses, each thenar eminence muscle has a specific source of innervation and blood supply; some thenar muscles are characterized by double innervation. There are usually several sources of blood supply; they can be divided into main – permanent and additional – non-permanent. The entry gates of nerves and arteries into the thenar muscles are located in their proximal third. In the flexor pollicis brevis, abductor pollicis, and adductor pollicis, the portals of nerves and arteries do not coincide. In the extensor pollicis muscles, except the flexor pollicis brevis muscle, the direction of the intramuscular nerves does not coincide with the direction of the intramuscular arteries. In the thenar muscles, large-diameter arteries lie deeper than the nerves. In practical work, the possibility of different innervation options for the thenar muscles should be taken into account.