Motor Nerve Conduction Block Estimation in Demyelinating Neuropathies by Deconvolution

A deconvolution method is proposed for conduction block (CB) estimation based on two compound muscle action potentials (CMAPs) elicited by stimulating a nerve proximal and distal to the region in which the block is suspected. It estimates the time delay distributions by CMAPs deconvolution, from which CB is computed. The slow afterwave (SAW) is included to describe the motor unit potential, as it gives an important contribution in case of the large temporal dispersion (TD) often found in patients. The method is tested on experimental signals obtained from both healthy subjects and pathological patients, with either Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) or Multifocal Motor Neuropathy (MMN). The new technique outperforms the clinical methods (based on amplitude and area of CMAPs) and a previous state-of-the-art deconvolution approach. It compensates phase cancellations, allowing to discriminate among CB and TD: estimated by the methods of amplitude, area and deconvolution, CB showed a correlation with TD equal to 39.3%, 29.5% and 8.2%, respectively. Moreover, a significant decrease of percentage reconstruction errors of the CMAPs with respect to the previous deconvolution approach is obtained (from a mean/median of 19.1%/16.7% to 11.7%/11.2%). Therefore, the new method is able to discriminate between CB and TD (overcoming the important limitation of clinical approaches) and can approximate patients’ CMAPs better than the previous deconvolution algorithm. Then, it appears to be promising for the diagnosis of demyelinating polyneuropathies, to be further tested in the future in a prospective clinical trial.

Electroneurographic Evaluation of Neural Impulse Transmission in Patients after Ischemic Stroke Following Functional Electrical Stimulation of Antagonistic Muscles at Wrist and Ankle in Two-Month Follow-Up

The available data from electroneurography (ENG) studies on the transmission of neural impulses in the motor fibers of upper and lower extremity nerves following neuromuscular functional electrical stimulation (NMFES) combined with kinesiotherapy in post-stroke patients during sixty-day observation do not provide convincing results. This study aims to compare the effectiveness of an NMFES of antagonistic muscle groups at the wrist and ankle and kinesiotherapy based mainly on proprioceptive neuromuscular facilitation (PNF). An ENG was performed once in a group of 60 healthy volunteers and three times in 120 patients after stroke (T0, up to 7 days after the incident; T1, after 21 days of treatment; and T2, after 60 days of treatment); 60 subjects received personalized NMFES and PNF treatment (NMFES+K), while the other 60 received only PNF (K). An ENG studied peripheral (M-wave recordings), C8 and L5 ventral root (F-wave recordings) neural impulse transmission in the peroneal and the ulnar nerves on the hemiparetic side. Both groups statistically differed in their amplitudes of M-wave recording parameters after peroneal nerve stimulation performed at T0 and T2 compared with the control group. After 60 days of treatment, only the patients from the NMFES+K group showed significant improvement in M-wave recordings. The application of the proposed NMFES electrostimulation algorithm combined with PNF improved the peripheral neural transmission in peroneal but not ulnar motor nerve fibers in patients after ischemic stroke. Combined kinesiotherapy and safe, personalized, controlled electrotherapy after stroke give better results than kinesiotherapy alone.

Effects of Neuromuscular Electrical Stimulation Combined with Repetitive Transcranial Magnetic Stimulation on Upper Limb Motor Function Rehabilitation in Stroke Patients with Hemiplegia

Objective. To investigate the effect of neuromuscular electrical stimulation (NMES) combined with repetitive transcranial magnetic stimulation (rTMS) on upper limb motor dysfunction in stroke patients with hemiplegia. Methods. A total of 240 stroke patients with hemiplegia who met the inclusion criteria were selected and randomly divided into 4 groups (60 cases in each group): control group, NMES group, rTMS group, and NMES + rTMS group. Before treatment and 4 weeks after treatment, we evaluated and compared the results including Fugl-Meyer assessment of upper extremity (FMA-UE) motor function, modified Barthel index (MBI), modified Ashworth scale (MAS), and motor nerve electrophysiological results among the 4 groups. Results. Before treatment, there was no significant difference in the scores of FMA-UE, MBI, MAS, and motor nerve electrophysiological indexes among the four groups, with comparability. Compared with those before treatment, the scores of the four groups were significantly increased and improved after treatment. And the score of the NMES + rTMS group was notably higher than those in the other three groups. Conclusion. NMES combined with rTMS can conspicuously improve the upper extremity motor function and activities of daily life of stroke patients with hemiplegia, which is worthy of clinical application and promotion.

Overview of Motor Nerve Damage in People with Diabetes Mellitus

Damage to motor nerves in people with diabetes increases the risk of a foot injury. This occurs because the damage results in changes in foot biomechanics, muscle atrophy, deformity, and increased pressure on the feet. So far, the examination of motor nerve damage in people with diabetes in agricultural areas such as the Jember Regency is still rarely touched by primary health services. The purpose of this study was to identify motor nerve damage in people with diabetes in the agriculture area of ​​the Jember Regency. This type of research is exploratory, descriptive, 102 respondents obtained by purposive sampling technique. Inclusion criteria in this study are age> 18 years; do not have DFU active, and did not experience amputation in both legs. Data collection uses instrument modification from MNSI (Michigan Neuropathy Screening Instrument) and MDNS (Michigan Diabetic Neuropathy Score). MNSI using in inspecting for deformity, while MDNS using for forms of physiological reflex damage and muscle strength. The analysis used in univariate and displayed in the frequency distribution. The results showed that the majority of respondents who suffer from DM are experienced in the middle adulthood category (71.6%), with a length of suffering more than five years (95.1%), and have a history of comorbidities (68.6%). The most common form of motor deformity damage was hallux valgus on the right and left legs (38.2%; 26.4%). Forms of motor damage in the form of muscle strength, severe damage to the abduction of the right and left legs (7.8%), and were found right or left toe extensions (1.9%; 2.9%). Motor damage in the form of no physiological reflexes was found in the right and left Quadriceps femoral (2%; 1%), and right or left leg Achilles (1%). The result of total motor damage assessment is that people with diabetes have decreased muscle strength in the right and left extremities (74.5%; 72.5%). This research shows that the majority of people with diabetes in the agricultur area of ​​the Jember Regency suffer motor nerve damage. Therefore, there is a need for preventive measures to prevent the worsening condition of people with diabetes.

Secondary Trigeminal Neuralgia: a Case Report and Literature Review of Red Flags

Introduction: Trigeminal neuralgia (TN) is characterized by recurrent paroxysmal brief episodes of electric shock-like pain along the trigeminal nerve distribution. Based on the underlying cause, current classification systems have classified TN into idiopathic, classical, and secondary TN. This manuscript presents a case report of a patient seen in the clinic with features of trigeminal neuralgia secondary to an intracranial lesion. Case description: A 39-year-old female presented to the clinic with a 15-month history of severe, intermittent, short-lasting episodes of pain affecting the left lower teeth, jaw, nose, and temporal region. The patient reported familiar shock-like pain during the physical examination when the skin of the left ala of the nose was lightly touched. The rest of the clinical examination was non-significant. The magnetic resonance imaging of the brain showed an approximately 20 mm wide lesion at the level of the cerebellopontine angle. After subsequent tests, the lesion was diagnosed as meningioma, and the patient was treated with stereotactic radiation therapy. Practical Implications: In up to 10 % of TN cases, the underlying cause can be due to a brain tumor. Although persistent pain, sensory or motor nerve dysfunction, gait disturbances, and other neurological signs may concurrently exist, raising a red flag for intracranial pathology, patients often present with pain alone as the heralding symptom of a brain tumor. Due to this, it is imperative that all patients suspected of having TN undergo an MRI of the brain as part of the diagnostic work-up.

Supercharged End-to-Side Anterior Interosseous to Ulnar Motor Nerve Transfer for Hirayama Disease: A Case Report

Hirayama disease is a rare condition of cervical myelopathy. Its early identification and correction can optimize functional outcomes. However, late presentation and some more severe cases may be associated with loss of hand function. Among the cases described, there are no reports of nerve transfers for this condition. We presented the first case report of a Hirayama disease of isolated ulnar nerve impairment managed with nerve transfer. Electroneuromyography showed isolated preganglionic involvement of C7, C8, and T1, with no sensory changes. The patient underwent nerve transfer with anterior interosseous nerve to ulnar nerve supercharge end-to-side, recovering hand function in 7 months.

Transport and Secretion of the Wnt3 Ligand by Motor Neuron-like Cells and Developing Motor Neurons

The vertebrate neuromuscular junction (NMJ) is formed by a presynaptic motor nerve terminal and a postsynaptic muscle specialization. Cumulative evidence reveals that Wnt ligands secreted by the nerve terminal control crucial steps of NMJ synaptogenesis. For instance, the Wnt3 ligand is expressed by motor neurons at the time of NMJ formation and induces postsynaptic differentiation in recently formed muscle fibers. However, the behavior of presynaptic-derived Wnt ligands at the vertebrate NMJ has not been deeply analyzed. Here, we conducted overexpression experiments to study the expression, distribution, secretion, and function of Wnt3 by transfection of the motor neuron-like NSC-34 cell line and by in ovo electroporation of chick motor neurons. Our findings reveal that Wnt3 is transported along motor axons in vivo following a vesicular-like pattern and reaches the NMJ area. In vitro, we found that endogenous Wnt3 expression increases as the differentiation of NSC-34 cells proceeds. Although NSC-34 cells overexpressing Wnt3 do not modify their morphological differentiation towards a neuronal phenotype, they effectively induce acetylcholine receptor clustering on co-cultured myotubes. These findings support the notion that presynaptic Wnt3 is transported and secreted by motor neurons to induce postsynaptic differentiation in nascent NMJs.

From decision to action: Detailed modelling of frog tadpoles reveals neuronal mechanisms of decision-making and reproduces unpredictable swimming movements in response to sensory signals

How does the brain process sensory stimuli, and decide whether to initiate locomotor behaviour? To investigate this question we develop two whole body computer models of a tadpole. The “Central Nervous System” (CNS) model uses evidence from whole-cell recording to define 2000 neurons in 12 classes to study how sensory signals from the skin initiate and stop swimming. In response to skin stimulation, it generates realistic sensory pathway spiking and shows how hindbrain sensory memory populations on each side can compete to initiate reticulospinal neuron firing and start swimming. The 3-D “Virtual Tadpole” (VT) biomechanical model with realistic muscle innervation, body flexion, body-water interaction, and movement is then used to evaluate if motor nerve outputs from the CNS model can produce swimming-like movements in a volume of “water”. We find that the whole tadpole VT model generates reliable and realistic swimming. Combining these two models opens new perspectives for experiments.

Factors Associated With Severity of Cubital Tunnel Syndrome at Presentation

Background: The outcomes of cubital tunnel syndrome surgery are affected by preoperative disease severity. The aim of this study was to identify factors associated with clinical and electrodiagnostic severity of cubital tunnel syndrome at presentation. Methods: We retrospectively identified 213 patients with electrodiagnostically confirmed cubital tunnel syndrome who underwent cubital tunnel surgery from July 2008 to June 2013. Our primary response variable was clinical cubital tunnel syndrome severity assessed by the McGowan grade. Our secondary response variables were sensory nerve action potential (SNAP) recordability, presence of fibrillations, and motor nerve conduction velocities (CVs) in the abductor digiti minimi (ADM) and first dorsal interosseous (FDI). Bivariate analysis was used to screen for factors associated with disease severity; significant variables were selected for multivariable regression analysis. Results: Older age was associated with higher McGowan grade and diabetes mellitus was associated with unrecordable SNAPs on bivariate analysis. No other variables met inclusion criteria for multivariable regression analysis for McGowan grade or unrecordable SNAPs. Multivariable regression analysis showed older age and higher Distressed Communities Index (DCI) to be associated with decreased motor nerve CVs in ADM. Multivariable regression analysis showed higher body mass index (BMI) and higher DCI to be associated with decreased motor nerve CVs in FDI. No variable was associated with the presence of fibrillations. Conclusions: A subset of patients with cubital tunnel syndrome may benefit from earlier referral for hand surgery evaluation and earlier surgery. Older patients, with higher BMI, with diabetes mellitus, and with economic distress are at higher risk for presentation with more severe disease.