Motor Unit Number Index of the Upper Trapezius: A Meta-Analysis and Cross-sectional Study of Its Reliability.

Motor unit number index of the upper trapezius (MUNIX-Trapezius) is a candidate biomarker for bulbar lower motor neuron function; however, reliability data is incomplete. To assess MUNIX-Trapezius reliability in controls, we conducted a systematic review, a cross-sectional study (n = 20), and a meta-analysis. We demonstrated a high inter- and intra-rater intraclass correlation (0.86 and 0.94, respectively), indicating that MUNIX-Trapezius is reliable with between-study variability moderated by age and MUNIX technique. With further validation, this measure can serve as a disease monitoring and response biomarker of bulbar function in the therapeutic development for amyotrophic lateral sclerosis.

Analysis of Gait Kinematics in Smart Walker-Assisted Locomotion in Immersive Virtual Reality Scenario.

The decline in neuromusculoskeletal capabilities of older adults can affect motor control, independence, and locomotion. Because the elderly population is increasing worldwide, assisting independent mobility and improving rehabilitation therapies has become a priority. The combination of rehabilitation robotic devices and virtual reality (VR) tools can be used in gait training to improve clinical outcomes, motivation, and treatment adherence. Nevertheless, VR tools may be associated with cybersickness and changes in gait kinematics. This paper analyzes the gait parameters of fourteen elderly participants across three experimental tasks: free walking (FW), smart walker-assisted gait (AW), and smart walker-assisted gait combined with VR assistance (VRAW). The kinematic parameters of both lower limbs were captured by a 3D wearable motion capture system. This research aims at assessing the kinematic adaptations when using a smart walker and how the integration between this robotic device and the VR tool can influence such adaptations. Additionally, cybersickness symptoms were investigated using a questionnaire for virtual rehabilitation systems after the VRAW task. The experimental data indicate significant differences between FW and both AW and VRAW. Specifically, there was an overall reduction in sagittal motion of 16%, 25%, and 38% in the hip, knee, and ankle, respectively, for both AW and VRAW compared to FW. However, no significant differences between the AW and VRAW kinematic parameters and no adverse symptoms related to VR were identified. These results indicate that VR technology can be used in walker-assisted gait rehabilitation without compromising kinematic performance and presenting potential benefits related to motivation and treatment adherence.

Phosphorus in alkaline soils of the semiarid region, Brazil: inorganic fractions, capacity factor, and availability.

The study was designed to quantify the contents of Pi fractions and correlate them with the P capacity factor of soils in the Brazilian semiarid region. We also evaluated the effect of soil P doses contact time and P availability for maize plants in alkaline soils of the Brazilian semiarid region. Soil samples were collected between the Piranhas-Açu (RN) and Jaguaribe (CE) rivers valleys. The maximum phosphate sorption capacity was highly correlated with the values of remaining P, indicating that it can be used as a measure to estimate the P capacity factor of these soils. Maximum P sorption capacity correlated with Fe2O3 and Ca2+ contents and pH values. These results demonstrate that P sorption is explained by P adsorption on the surface of iron oxides and by its precipitation with Ca2+ in alkaline soils. The contact time increases promote plant P contents decreased substantially in the first 30 to 60 days after fertilization and decreased until 120 days of incubation but then tended to stabilize at the longest soil P contact times.

The clay content and P-remnant estimate the P capacity factor in alkaline soils.In alkaline soils, there is a predominance of P­Ca and P­Fe.The availability of P stabilizes after 120 days.The largest corn biomass occurs between the P doses of 256­288 mg dm⁻³.

Ischaemic lumbosacral plexopathy following aortic dissection.

A 57-year-old man was diagnosed with acute myocardial infarction and Stanford type A aortic dissection that had spread to the common iliac arteries. He underwent a Bentall procedure for vascular repair. Immediately after surgery, he developed numbness and severe weakness in his left leg. On examination, he had hypotonia, absent deep tendon reflexes, weakness in the left leg (Medical Research Council (MRC) scale for muscle strength - 0/5 distal, 3/5 proximal) and reduced sensation in the left leg. Electromyography confirmed subacute involvement of the left lumbar and lumbosacral plexus. MR scan of the lumbar plexus showed diffuse muscle oedema involving the left gluteus maximus. We diagnosed ischaemic lumbosacral plexopathy secondary to extensive aorta dissection and internal iliac artery occlusion. We discuss the clinical features of ischaemic plexopathy and the diagnostic approach and review the vascular anatomy of the lumbosacral plexus.

The Intersection Between Cerebellar Ataxia and Neuropathy: a Proposed Classification and a Diagnostic Approach.

Neuropathy is a common associated feature of different types of genetic or sporadic cerebellar ataxias. The pattern of peripheral nerve involvement and its associated clinical features can be an invaluable aspect for narrowing the etiologic diagnosis in the investigation of cerebellar ataxias. In this review, we discuss the differential diagnosis of the intersection between peripheral nerve and cerebellar involvement, and classify them in accordance with the predominant features. Genetics, clinical features, neuroimaging, and neurophysiologic characteristics are discussed. Furthermore, a diagnostic approach for cerebellar ataxia with neuropathy is proposed according to the different clinical characteristics. This is an Educational and Descriptive review with the aim of medical education for the approach to the patients with cerebellar ataxia and neuropathy. The diagnostic approach to the patient with cerebellar ataxia with neuropathy requires a detailed medical history, phenotyping, characterization of disease progression and family history. Neuroimaging features and the neurophysiological findings play pivotal roles in defining the diagnosis. Establishing an organized classification method for the disorders based on the clinical features may be very helpful, and could be divided as those with predominant cerebellar features, predominant neuropathic feature, or conditions with both cerebellar ataxia and neuropathy. Second, determining the mode of inheritance is critical on cerebellar ataxias: autosomal dominant and recessive cerebellar ataxias, mitochondrial or sporadic types. Third, one must carefully assess neurophysiologic findings in order to better characterize the predominant pattern of involvement: damage location, mechanism of lesion (axonal or demyelinating), motor, sensory or sensory motor compromise, large or small fibers, and autonomic system abnormalities.

Optimal E2 (reference) electrode placement in fibular motor nerve conduction studies recording from the tibialis anterior muscle.

INTRODUCTION: In this study we aimed to determine the contribution of the E2 (reference electrode) to the compound muscle action potential (CMAP) amplitude during fibular motor recording to the tibialis anterior (TA) when E2 is placed over routine referential vs. alternative sites. METHODS: The CMAP was obtained from 10 healthy subjects, using the active electrode (E1) over sites routinely used as E2 for the TA, whereas the E2 was over the contralateral knee. The same procedure was performed with the E1 over alternative E2 sites. RESULTS: Significant electrical signal was captured over routine E2 placement sites. Among the tested alternative E2 sites, the ipsilateral patella (especially its medial aspect) was the most electrically silent. DISCUSSION: Using alternative E2 sites with near isoelectric recordings can optimize near-field potential measurement in the fibular motor recording to the TA and represents a more accurate way of measuring nerve and muscle function. Muscle Nerve 59:249-253, 2019.

Tonic pupils: an unusual autonomic involvement in chronic inflammatory demyelinating polyneuropathy (CIDP).

BACKGROUND: Chronic inflammatory demyelinating polyneuropathy (CIDP) is a neuropathy which affects mainly large myelinated axons and has a typically mild autonomic dysfunction mainly from postganglionic nerve fiber involvement. CASE REPORT: We report here an acute onset CIDP initially diagnosed as Guillain-Barré syndrome (GBS), unresponsive to treatment with intravenous immunoglobulin (IVIg), which later responded to plasmapheresis and corticoids. The patient had a markedly distal demyelination, prominent cranial nerve involvement and, interestingly, bilateral fixed dilated pupils. Despite complete clinical recovery, this neurological sign remained. CONCLUSIONS: Tonic pupils have previously been described in different neurologic conditions, including GBS, but not yet in acute onset CIDP or in variants with predominantly distal demyelination. It differs from the classical Adie's pupil because it lacks the light-near dissociation. This case report expands the range of possible autonomic signs in acute onset CIDP, which could help physicians establish optimal treatment strategies earlier on.

Respiratory deposition of ultrafine welding fume particles.

The inhalation and the deposition of welding-generated ultrafine particles in welders' respiratory tracts have been linked to severe pulmonary impairments. In the present study, a mobile aerosol lung deposition apparatus (MALDA) was developed and applied to study the respiratory deposition of ultrafine welding fume particles. The MALDA was constructed with a set of physiologically representative human tracheobronchial airway replicas made with high-resolution 3D printers. Ultrafine welding fume particles were generated in a welding fume chamber and delivered to the MALDA. A series of respiratory deposition experiments were carried out using the MALDA to investigate the deposition of ultrafine welding fume particles in different airway generations of the tracheobronchial airways. The results showed that the fractional deposition of ultrafine welding fume particle in the human tracheobronchial airways down to the 9th airway generation could be readily and systematically measured by the MALDA. The estimated cumulative respiratory deposition ranged from approximately 9-31% for ultrafine welding fume particles between 10 and 100 nm in diameter. The results acquired demonstrated that the MALDA developed has the potential to become a useful apparatus in the future to estimate the respiratory deposition of ultrafine particles in real workplaces.

Motor unit number index and neurophysiological index as candidate biomarkers of presymptomatic motor neuron loss in amyotrophic lateral sclerosis.

INTRODUCTION: Our objective was to determine the utility of motor unit number index (MUNIX) and neurophysiological index (NI) as surrogate biomarkers of disease progression in limbs without clinical signs of lower motor neuron (LMN) involvement from patients with slowly progressive amyotrophic lateral sclerosis (ALS). METHODS: Patients with slowly progressive ALS and at least 1 clinically unaffected limb were prospectively enrolled. Clinical signs of LMN loss and results from hand-held dynamometer (HHD), revised ALS Functional Rating Scale (ALSFRS-R), mean-MUNIX (from 3 different muscles), and NI were longitudinally recorded. RESULTS: Eighteen patients with 43 presymptomatic muscles were evaluated. Twenty-seven muscles remained clinically unaffected during study, with stable ALSFRS-R subscores and HHD measures. However, a significant decline in mean-MUNIX and NI was detected. DISCUSSION: Mean-MUNIX and NI were more sensitive than clinical measures at detecting LMN loss in presymptomatic limbs from patients with slowly progressive ALS. Therefore, these electrophysiological biomarkers should be included in early study phases as meaningful outcome measures. Muscle Nerve 58: 204-212, 2018.

Non-motor and Extracerebellar Features in Spinocerebellar Ataxia Type 2.

Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant degenerative disease. Pathological studies have demonstrated not only cerebellar and brainstem atrophy, but substantia nigra, motoneurons, basal ganglia, thalamus, and peripheral nerves involvement. These findings may explain non-motor and extra-cerebellar features in SCA2. We accessed the non-motor symptoms and extra-cerebellar signs in SCA2 patients in order to provide a better understanding on pathophysiological mechanisms and natural history of brain degeneration in the disease. Thirty-three SCA2 patients were evaluated and compared with 26 healthy subjects. We investigated the following variables: sleep disorders, cognitive deficit, olfactory impairment, urinary dysfunction, psychiatric symptoms, cramps, pain, movement disorders, and weight loss. SCA2 had a high frequency of REM sleep behavior disorder (48.48 %, N = 16) as well as excessive daytime sleepiness (42.42 %, N = 14). Chorea was present in 15.15 % (N = 5), dystonia in 27.27 % (N = 9), and parkinsonism in 27.27 % (N = 9). Slow saccadic pursuit was present in 87.87 % (N = 29) and ophtalmoparesis in 78.78 % (N = 26) of patients. Regarding sleep disorders, 18.18 % (N = 6) of patients had restless leg syndrome. Dysphagia was present in 39.39 % (N = 13), weight loss 24.24 % (N = 8), and urinary dysfunction 27.27 % (N = 9). Cramps was present in only 6 % of patients (N = 2). This study highlighted the high frequency of non-motor symptoms and extra-cerebellar signs in SCA2. Our findings demonstrate the widespread of nervous system involvement in SCA2 patients and contribute to better understand the natural history of brain degeneration in this genetic condition.

Improving the reproducibility of motor unit number index.

INTRODUCTION: Reproducibility is an important aspect of any method intended to be a marker of disease progression. In this study we investigated approaches for improving motor unit number index (MUNIX) reproducibility. METHODS: We used the intraclass correlation coefficient (ICC) and the coefficient of variation (CV) to study reproducibility in healthy subjects. We tested reproducibility between test and retest of a single MUNIX from 3 different muscles (S-MUNIX) and also of the mean of a set of 3 measurements from these same muscles (M-MUNIX). RESULTS: M-MUNIX was more reproducible than S-MUNIX. The CV showed a greater improvement than the ICC in all 3 muscles. CONCLUSIONS: M-MUNIX may be a valuable approach for following motor unit loss, because it is more replicable than MUNIX. This may be especially relevant in amyotrophic lateral sclerosis patients, in whom MUNIX variability is higher than in healthy individuals. Muscle Nerve, 2016 Muscle Nerve 55: 635-638, 2017.

Pattern of Peripheral Nerve Involvement in Spinocerebellar Ataxia Type 2: a Neurophysiological Assessment.

Peripheral neuropathy is frequent in spinocerebellar ataxia type 2 (SCA2), but the pattern and characteristics of nerve involvement are still an unsettled issue. This study aimed to evaluate the prevalence, extent, and distribution of nerve involvement in SCA2 patients through neurophysiological studies. Thirty-one SCA2 patients and 20 control subjects were enrolled in this study. All subjects were prospectively evaluated through electromyography, including nerve conduction, needle electromyography in proximal and distal muscles of the upper and lower limbs, and sural radial amplitude ratio (SRAR). We aimed to differentiate distal axonopathy from diffuse nerve commitment, characterizing neuronopathy. Nerve involvement was observed in 83.6 % (26 individuals) of SCA2 patients. Among these, 19 had diffuse sensory abnormalities on nerve conduction predominantly on the upper limbs, with diffuse chronic denervation on needle electromyography and elevated SRAR values. Four individuals had only diffuse sensory involvement, and 2 had only motor involvement on needle evaluation and normal nerve conduction. These were interpreted as neuronopathy due to the diffuse distribution of the involvement. One individual had distal sensory axonopathy, with lower limb predominance. In this study, we found neuronopathy as the main pattern of nerve involvement in SCA2 patients and that motor involvement is a frequent feature. This information brings new insights into the understanding of the pathophysiology of nerve involvement in SCA2 and sets some key points about the phenotype, which is relevant to guide the genetic/molecular diagnosis.

Neurophysiological studies and non-motor symptoms prior to ataxia in a patient with machado-joseph disease: trying to understand the natural history of brain degeneration.

Spinocerebellar ataxia type 3 or Machado-Joseph disease is the most common spinocerebellar ataxia. In this neurological disease, anatomical, physiological, clinical, and functional neuroimaging demonstrate a degenerative process besides the cerebellum. We performed neurophysiological and neuroimaging studies-polysomnography, transcranial sonography, vestibular-evoked myogenic potential, single-photon emission computed tomography (SPECT) with (99m)Tc-TRODAT-1, and a formal neuropsychological evaluation in a patient with sleep complaints and positive testing for Machado-Joseph disease, without cerebellar atrophy, ataxia, or cognitive complaints. Polysomnography disclosed paradoxical high amplitude of submental muscle, characterizing REM sleep without atonia phenomenon. Transcranial sonography showed hyperechogenicity of the substantia nigra. There was an absence of vestibular-evoked myogenic potentials on both sides in the patient under study, in opposite to 20 healthy subjects. Brain imaging SPECT with (99m)Tc-TRODAT-1 demonstrated a significant lower DAT density than the average observed in six healthy controls. Electroneuromyography was normal. Neuropsychological evaluation demonstrated visuospatial and memory deficits. Impairment of midbrain cholinergic and pontine noradrenergic systems, dysfunction of the pre-synaptic nigrostriatal system, changes in echogenicity of the substantia nigra, and damage to vestibulo-cervical pathways are supposed to occur previous to cerebellar involvement in Machado-Joseph disease.

General low alertness in people with obstructive sleep apnea.

STUDY OBJECTIVES: In patients with obstructive sleep apnea (OSA), a previous study using a Go/No-Go task reported an average attention deficit. However, the temporal dynamics of such a deficit are unknown. Here, we investigated whether attention deficits in different subdomains increased as the test progressed. We also investigated the effect of target frequency and speed of stimulus presentation on performance. METHODS: Twenty-seven untreated people with OSA and 27 age- and sex-matched controls underwent a 15-minute Go/No-Go task, divided into 6 blocks. Each block was subdivided into 3 different interstimulus intervals (1, 2, and 4 seconds). Three blocks had a low and three had a high target probability (20% and 80%, respectively). Reaction time (alertness), variability of reaction time (sustained attention), commission errors (response inhibition), and omission errors (focused attention) were measured. RESULTS: Alertness was lower in the group with OSA compared with controls, as evidenced by a significantly higher average reaction time. This effect was seen from the start of the task and continued until the end but did not increase in test progression. The temporal pattern of intrinsic alertness deficits in patients with OSA was found to be independent of target frequency or interstimulus interval. CONCLUSIONS: The primary attention problem in OSA is on the alertness subdomain irrespective of the number of required responses or speed of stimulus presentation. The present results support the notion that OSA is distinct from other neurological and psychiatric conditions, such as depression or chronic pain. The results also suggest significant concerns regarding daily life activities (eg, driving). CITATION: de Souza Bezerra ML, van Duinkerken E, Simões E, Schmidt SL. General low alertness in people with obstructive sleep apnea. J Clin Sleep Med. 2024;20(5):689-698.

Psychological factors show limited association with the severity of Achilles tendinopathy.

BACKGROUND: This study aimed to investigate the association between psychosocial factors and the severity of Achilles tendinopathy, along with exploring their potential link to the pain's duration. METHODS: A cross-sectional study involving 111 individuals with Achilles tendon pain was conducted. METHODS: A cross-sectional study involving 111 individuals with Achilles tendon pain was conducted. Various psychological factors were assessed using the Pain Catastrophizing Scale, Chronic Pain Self-Efficacy Scale (CPSS), Tampa Scale for Kinesiophobia, and Hospital Anxiety and Depression Scale (HAD). Additionally, the severity of Achilles tendon pain was evaluated using the Victorian Institute of Sport Assessment-Achilles questionnaire (VISA-A-Br). Regression analyses were employed to determine the association of these psychosocial factors with pain severity and duration. RESULTS: Self-efficacy for chronic pain showed a slight association with Achilles tendon pain severity (ß = 0.42 [95% CI: 0.06 to 0.16], p = 0.001), explaining only 19% of the dependent variable. The other variables, including anxiety, depression, pain catastrophizing, and fear of movement, did not exhibit significant associations. CONCLUSION: The study suggests that psychological factors demonstrate limited association with the severity of Achilles tendinopathy. While self-efficacy for chronic pain was weakly associated, its clinical relevance remains uncertain. Future research, particularly longitudinal studies, should explore the influence of psychosocial factors on treatment adherence and response to enhance management strategies for Achilles tendon pain.

Pattern of peripheral nerve involvement in Machado-Joseph disease: neuronopathy or distal axonopathy? A clinical and neurophysiological evaluation.

OBJECTIVE: Neuropathy is a well-recognized feature in spinocerebellar ataxia type 3 (SCA3) or Machado-Joseph disease (MJD), but the pattern of neuropathy is still a matter of debate. This study aimed to evaluate peripheral nerve involvement in MJD patients. Neurophysiological and clinical data were analyzed to distinguish neuronopathy from length-dependent distal axonopathy. METHODS: In the present study we evaluated 26 patients with clinical and molecular-proven MJD and investigated their peripheral nerve involvement. Neurophysiological and clinical data were compared and correlated aiming to distinguish neuronopathy from distal axonopathy. RESULTS: The neurophysiological evaluation showed that 42.3% of the patients had polyneuropathy. Among these patients, 81.8% presented neuronopathy. CONCLUSION: We concluded that neuronopathy is the most common form of peripheral nerve involvement in MJD patients.

The hypothalamic-pituitary-adrenal axis and the central monoaminergic systems: a pathophysiological link to insomnia with clinical implications.

The authors present a theoretical overview of the hypothalamic-pituitary-adrenal axis and the central monoaminergic systems, focusing on a putative pathophysiological relationship to insomnia complaints. Insomnia is an independent and self-perpetuating disorder that requires diagnostic and therapeutic attention in the presence of concomitant disorders, likely with bidirectional influence. An adequate understanding of such mechanisms can help for a better understanding of the interplay between clinical features, neurotransmitters, and the adrenal hypothalamic-pituitary axis may help clinicians to better manage insomnia patients.

Clinimetric properties of the knee extension prone test (KEPT): A new method to assess knee hyperextension deficit.

INTRODUCTION: The knee extension prone test (KEPT) can be a low-cost and affordable alternative for this assess knee hyperextension deficit. OBJECTIVE: To analyze concurrent validity and reliability of a new method for assessing knee extension prone (knee extension prone test; KEPT). METHODS: Participants were divided into two groups: Group 1 comprised healthy participants (HG) and Group 2 comprised participants with a history of knee injury (IG). Two examiners performed the following evaluations: (1) lateral knee goniometry, (2) anterior tibial inclinometry, (3) lateral photogrammetry in supine, (4) lateral photogrammetry in prone, and (5) KEPT. Concurrent validity was analyzed by Pearson's linear correlation coefficient (r), and intra- and inter-examiner reliability were analyzed by intraclass correlation coefficient (ICC). RESULTS: KEPT demonstrated good intra-examiner (ICC = 0.85, 95% CI = 0.75-0.89) and excellent inter-examiner (ICC = 0.92, 95% CI = 0.88-0.94) reliability. The standard error of measurement was 0.47° and 1.30° and the minimum detectable change was 2.35° and 6.5° for intra- and inter-examiner agreement, respectively. Concurrent validity of KEPT ranged from moderate to good (r = 0.54-0.78, p < 0.01). CONCLUSION: KEPT is a valid and reliable method for assessing knee hyperextension deficit in both healthy individuals and patients with knee injuries.

Is neuropathy involved with restless legs syndrome in Machado-Joseph disease?

OBJECTIVE: To evaluate a group of spinocerebellar ataxia type 3 (SCA3) or Machado-Joseph disease (MJD) (SCA3/MJD) patients and assess whether there is an association between neuropathy and serum ferritin levels and restless legs syndrome (RLS). METHODS: Twenty-six SCA3/MJD patients underwent electromyography studies to check for neuropathy. Their serum ferritin levels were measured as well. These findings were evaluated based on the presence or not of RLS and its severity. RESULTS: The proportion of neuropathy in the RLS group was not significantly higher compared to the non-RLS group (23 vs. 15%, Fisher's exact test, p = 1.000). Furthermore, no association was found between RLS and ferritin levels. CONCLUSION: We found no correlation between neuropathy or ferritin levels and RLS in SCA3/MJD patients.

Impact of ammunition and military explosives on human health and the environment.

OBJECTIVE: To review the literature concerning the risks associated with the main xenobiotics contained in military ammunition and explosive residues and damage to human and environmental health. METHODOLOGY: Using "ammunition", "military", "environmental", "health", "explosive", "metal", "TNT", "RDX", "pollution", and "contamination" as search terms, a large database, namely ISI Web of Knowledge and PubMed, was searched for studies on military ammunition and explosive residues from 1989 to 2010. Other sources used to conduct the search included the library of the Toxicology Laboratory of the Center for Workers' Health and Human Ecology (CESTEH) at the National School of Public Health. RESULTS: In total, 15 different combinations were used with the search words above and 708 papers were found. Among them, 76 papers concerned this review. More than 12 references of interest were discovered in the library of the CESTEH. The results were organized into metals, dinitrotoluene, trinitrotoluene (TNT), and royal demolition explosive (RDX), showing their main uses, occurrence in the environment, the current toxic effects to human and environmental health, and remediation possibilities. CONCLUSION: Because military activities can cause the acute and chronic exposure of human beings, the public administration must aim politics towards suitable environmental management.