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Introduction: Even if electromyography (EMG) is routinely used to confirm the diagnosis of amyotrophic lateral sclerosis (ALS), few studies have analysed the correlation between electrophysiological parameters and clinical characteristics of ALS. We assessed if the quantification of active denervation (AD) and chronic denervation (CD) provides clinicians with information about phenotype, disease progression and survival in ALS patients. Methods: We studied a cohort of 689 ALS patients recording the following parameters: age and site of onset, survival, MRC scale for muscle strength evaluation, burden of upper and lower motor signs as measured with specific scales (PUMNS and LMNS, respectively), ALSFRS-R, progression rate (ΔFS), MITOS and King's Staging systems (KSS). We performed EMG on 11 muscles, and calculated semiquantitative AD and CD scores for each limb, as well as for the bulbar and spinal regions. Results: We found a positive correlation between AD and CD scores with LMNS (respectively p = 4.4 × 10–37 and p = 2.8 × 10–45) and a negative correlation with MRC (respectively p = 4.5 × 10–35 and p = 3.0 × 10–35). Furthermore, patients with higher spinal AD and CD scores had significantly lower ALSFRS-R scores, and higher KSS and MITOS stages. Conversely, only AD was associated to higher ΔFS (p = 1.0 × 10–6) and shorter survival (p = 1.1 × 10–5). Conclusion: Our results confirmed that EMG examination represents not only a diagnostic instrument, but also a prognostic tool. In this context, AD seems to be a reliable predictor of disease's progression and survival while CD better describes functional disability. [ABSTRACT FROM AUTHOR]

Clinical neurophysiology constructs a wealth of dynamic information pertaining to the integrity and function of both central and peripheral nervous systems. As with many technological fields, there has been an explosion of data in neurophysiology over recent years, and this requires considerable analysis by experts. Computational algorithms and especially advances in machine learning (ML) have the ability to assist with this task and potentially reveal hidden insights. In this update article, we will provide a brief overview where such technology is being applied in clinical neurophysiology and possible future directions. [ABSTRACT FROM AUTHOR]

Motor disability in MS is commonly assessed by the Expanded Disability Status Scale (EDSS). Categorical rating scales are limited by subjective error and inter-rater variability. Therefore, objective and quantitative measures of motor disability may be useful to supplement the EDSS in the setting of clinical trials. It was previously shown that grip-force-variability (GFV) is increased in MS. We hypothesized that GFV may be an objective measure of motor disability in MS. To investigate whether the increase in GFV in MS is correlated to the clinical disability as assessed by the EDSS and to microstructural changes in the brain as assessed by diffusion tensor imaging, GFV was recorded in a grasping and lifting task in 27 MS patients and 23 controls using a grip-device equipped with a force transducer. The EDSS was assessed by neurologists experienced in MS. Patients underwent diffusion tensor imaging at 3T to assess the fractional anisotropy (FA) of the cerebral white matter as a measure of microstructural brain integrity. GFV was increased in MS and correlated to changes in the FA of white matter in the vicinity of the somatosensory and visual cortex. GFV also correlated with the EDSS. GFV may be a useful objective measure of motor dysfunction in MS linked to disability and structural changes in the brain. Our data suggests that GFV should be further explored as an objective measure of motor dysfunction in MS. It could supplement the EDSS, e.g., in proof of concept studies. [ABSTRACT FROM AUTHOR]

Sensory neuronopathies (SN) represent a subgroup of peripheral nervous system disorders which are becoming increasingly recognized. Despite a few reports of autonomic dysfunction, this complication has not been fully appreciated. Autonomic function was quantified through tests of sympathetic and parasympathetic function (forming the Autonomic Tests Score, ATS), and through a 40-item questionnaire assessing autonomic symptoms (constituting the Autonomic Questionnaire Score, AQS). Twenty patients were enrolled. Forty-six age- and gender-matched controls were evaluated for the AQS and 15 for the ATS. All patients reported symptoms of autonomic dysfunction. Of the patients, 60% had one or more abnormal cardiovagal test, 60% orthostatic hypotension and 20% abnormal pupillary function. Their ATS was significantly different from the controls ( p < 0.0001). Neither the ATS nor AQS were different between groups of SN associated disorders. Autonomic dysfunction is a frequent and important complication in SN, and it does not seem to be related to a specific etiology, as previously thought. [ABSTRACT FROM AUTHOR]

Patients with carpal tunnel syndrome (CTS) complain of motor symptoms. The study is aimed to understand which features are associated with the presence of motor symptoms in CTS. We recruited 282 consecutive CTS patients. After selection, 129 patients (203 hands) were included. Patients were asked about the presence and severity of hand weakness (HW) and hand clumsiness (HC). They underwent a self-administered questionnaire on symptoms, clinical evaluation and neurographic study. Quantitative sensory testing (QST) was performed on the patients with unilateral right CTS. HW and HC may be found in 56 % and 48 % of CTS hands, respectively. HW was related to the severity of sensory symptoms (pain, numbness and tingling) but not to clinical-neurographic measures of median nerve involvement. HC was related to the severity of sensory symptoms and to the clinical-neurographic signs of motor but not sensory nerve damage. Motor symptoms were significantly more frequent in right hands. QST showed a relationship between the presence and severity of HW and HC and the warm threshold. Motor symptoms may be found in approximately half of CTS hands. Clinical and neurographic signs of median nerve motor damage appear to be poorly correlated to motor symptoms. The factor that can help reconcile the discrepancy between motor symptoms and motor signs is pain. Pain modulation on motor function may take place at various anatomical levels in CTS. Nociceptive C-fibers may be involved in pain-motor interactions finally leading to motor symptoms. [ABSTRACT FROM AUTHOR]

We studied the time-course of a levodopa oral bolus effects on the kinematics of patients affected by a mild akinetic–rigid form of idiopathic Parkinson’s disease (PD). Eleven PD patients were evaluated: a) in OFF–state, that is before their first medication or after its withdrawal, b) in ON–state, that is at 1/2, 1, 2, 3, 4, 5, 6, 24, 30 and 48 hours after the administration of 250 mg of levodopa plus 25mg of carbidopa. The main kinematics (i. e.movement time, peak of velocity, peak of acceleration and peak of deceleration) of pointing movements to six target–stimuli placed on the horizontal plane of a table were recorded. Clinical conditions were assessed according to the Motor Examination section of the Unified Parkinson’s Disease Rating Scale. The levopoda bolus had stable clinical effects only within the first six hours from its administration. The decline of the clinical response was marked by the changes of peak acceleration whereas other kinematics (i. e. movement time and the peak of velocity) changed also in the late observations (24, 30 and 48 hours after drug intake). The dissociation between the persistent improvement on movement time on peak velocity and the rapid deterioration of levodopa effects on early kinematics (i. e. peak acceleration) could be accounted for by a progressive decline in movement programming. [ABSTRACT FROM AUTHOR]

A 19-year-old male twin pair were concordant for suffering from Gilles de la Tourette's syndrome in different forms and severity. CT revealed ventricular asymmetries of varying degree within the normal range and there were no neurophysiological abnormalities. The interrelationship of genetic and environmental factors in phenotyping the syndrome is discussed. [ABSTRACT FROM AUTHOR]