Ultrasound-guided-electromyography in plegic muscle: Usefulness of nerve stimulation.

INTRODUCTION/AIMS: In traumatic nerve lesions (TNLs), motor unit potentials (MUPs) may be difficult to detect in early injury. Ultrasound-guided electromyography (US-EMG) can aid in identifying areas of muscle activation, but its sensitivity can be improved. In this study we compare the sensitivity of US-EMG alone with US-EMG after peripheral nerve stimulation (NC-US-EMG) to better identify active muscle regions. METHODS: In this prospective study, 32 patients with severe TNLs were evaluated with standard EMG (ST-EMG), US-EMG, and NC-US-EMG at baseline (T0), after 2 to 3 months (T1), and after 5 to 6 months (T2). RESULTS: NC-US-EMG was more sensitive in detecting MUPs compared with US-EMG and ST-EMG at T0 (19 patients vs 14 and 5 patients, respectively). In addition, both US-guided techniques were more sensitive than ST-EMG in detecting MUPs (ST-EMG vs US-EMG: P = .014; ST-EMG vs NC-US-EMG: P = .003). At T1, ST-EMG remained less sensitive NC-US-EMG (P = .019). No significant differences were observed among the three techniques at T2. DISCUSSION: In the evaluation of severe TNLs, the combination of peripheral nerve stimulation and US increases the sensitivity of EMG for MUP detection at baseline and 2 to 3 months postinjury.

Measuring Gait Quality in Parkinson's Disease through Real-Time Gait Phase Recognition.

Monitoring gait quality in daily activities through wearable sensors has the potential to improve medical assessment in Parkinson's Disease (PD). In this study, four gait partitioning methods, two based on thresholds and two based on a machine learning approach, considering the four-phase model, were compared. The methods were tested on 26 PD patients, both in OFF and ON levodopa conditions, and 11 healthy subjects, during walking tasks. All subjects were equipped with inertial sensors placed on feet. Force resistive sensors were used to assess reference time sequence of gait phases. Goodness Index (G) was evaluated to assess accuracy in gait phases estimation. A novel synthetic index called Gait Phase Quality Index (GPQI) was proposed for gait quality assessment. Results revealed optimum performance (G < 0.25) for three tested methods and good performance (0.25 < G < 0.70) for one threshold method. The GPQI resulted significantly higher in PD patients than in healthy subjects, showing a moderate correlation with clinical scales score. Furthermore, in patients with severe gait impairment, GPQI was found higher in OFF than in ON state. Our results unveil the possibility of monitoring gait quality in PD through real-time gait partitioning based on wearable sensors.

Secondary posterior interosseous nerve lesions associated with humeral fractures.

INTRODUCTION: Radial nerve lesions associated with humeral shaft fractures are the most common traumatic nerve lesions observed with long bone fractures. Secondary indirect posterior interosseous nerve (PIN) lesions can be associated with traumatic radial nerve palsy. The aim of this study was to identify cases of traumatic double-site radial nerve involvement through ultrasound (US). METHODS: Patients with traumatic radial nerve lesions referred to our laboratory from January 2010 to January 2014 were evaluated. RESULTS: Of the 35 patients, 18 had US evidence of a radial nerve lesion at the fracture site associated with secondary PIN involvement at the arcade of Frohse. CONCLUSIONS: Multiple-site nerve lesions are difficult to demonstrate through electrodiagnostic tests. In our case series, half of the patients with traumatic radial nerve damage had US evidence of PIN injury. Prospective studies with follow-up are needed to determine the clinical and prognostic relevance of this finding and the best therapeutic approach.

Neuromyelitis optica spectrum disorder as a paraneoplastic manifestation of lung adenocarcinoma expressing aquaporin-4.

BACKGROUND: The observations of neuromyelitis optica spectrum disorders (NMOSD) occurring in the setting of cancer suggest that aquaporin-4 (AQP4) autoimmunity may in some cases be paraneoplastic. RESULTS: We describe a 72-year-old patient who developed a longitudinally extensive transverse myelitis associated with AQP4 autoantibodies in the setting of a lung adenocarcinoma recurrence. AQP4 expression was demonstrated in tumor cells. IgG in patient's cerebrospinal fluid bound to tumor cells co-localizing with AQP4 immunoreactivity. CONCLUSIONS AND RELEVANCE: This case expands the spectrum of paraneoplastic AQP4 autoimmunity highlighting the importance of considering an oncological screening in patients with late-onset NMOSD.

Ultrasound diagnosis of bony nerve entrapment: case series and literature review.

INTRODUCTION: Nerve entrapment due to osseous callus formation is a rare complication after bone fracture. Electrodiagnostic studies and routine radiographic imaging often fail to demonstrate the pathology. The diagnosis is difficult and is often made incidentally upon surgical exploration. Nerve ultrasonography has not been used routinely to assess such lesions. METHODS: We report 5 cases of nerve entrapment in osseous callus after fractures that occurred in 2011 and 2012. The diagnosis was made by ultrasound (US). We then performed a review of the relevant literature. CONCLUSIONS: US is becoming an invaluable tool for diagnosing peripheral nerve entrapments. The current cases suggest that nerve US should be strongly considered as an adjunctive diagnostic tool for nerve palsies developing after trauma.

Pain and the alpha-sleep anomaly: a mechanism of sleep disruption in facioscapulohumeral muscular dystrophy.

OBJECTIVE: To measure the presence of the alpha-sleep anomaly in facioscapulohumeral muscular dystrophy (FSHD) and to evaluate the association between the sleep electroencephalogram (EEG) pattern and the presence of musculoskeletal pain. DESIGN: Cross-sectional study. SETTING: Sleep laboratory. SUBJECTS: Fifty-five consecutive adult FSHD patients, 26 women and 29 men, age 49.6 ± 15.1 years (range 18-76). INTERVENTIONS: Questionnaires and polysomnography. OUTCOME MEASURES: Patients were asked to indicate if in the 3 months before the sleep study they presented persisting or recurring musculoskeletal pain. Patients who reported pain were asked to fill in the Italian version of the Brief Pain Inventory and the McGill Pain questionnaire, and a 101-point visual analog scale (VAS) for pain intensity. Polysomnographic recordings were performed. EEG was analyzed by means of Fast Fourier Transform. Four power spectra bands (δ 0-4 Hz, θ 4-8 Hz, α 8-14 Hz, ß 14-32 Hz) were computed. Sleep macrostructure parameters and alpha/delta EEG power ratio during non rapid eye movement (NREM) sleep were compared between patients with and without pain. RESULTS: Forty-two patients in our sample reported chronic pain. VAS mean score was 55.2 ± 23.8 (range 10-100), pain rating index score was 13.8 ± 10.2, and present pain intensity was 2.5 ± 0.8. The statistical analysis documented an increased occurrence of the alpha and beta rhythms during NREM sleep in FSHD patients with pain. Significant correlations were observed between the alpha/delta power ratio during NREM sleep and pain measures. CONCLUSIONS: Chronic musculoskeletal pain is frequent in FSHD patients, and it represents a major mechanism of sleep disruption.

Nerve ultrasound follow-up in a child with Guillain-Barré syndrome.

INTRODUCTION: Nerve ultrasound has been used increasingly in neurophysiology laboratories, but data on Guillain-Barré syndrome (GBS) are still limited, and no follow-up studies are available. CASE REPORT: An 8-year-old boy was admitted with severe demyelinating GBS. Serial neurophysiological evaluations were performed initially and in follow-up. Ultrasound studies showed diffuse and heterogeneous nerve swelling and focal enlargement of single fascicles inside the nerve. Together with clinical and electrophysiological improvement, progressive normalization of ultrasound changes was seen. CONCLUSIONS: Ultrasound demonstrated structural nerve abnormalities in GBS. These changes normalized as the patient improved clinically and electrophysiologically. Further studies are needed to elucidate the diagnostic and prognostic value of ultrasound in GBS.

Intra- and internerve cross-sectional area variability: new ultrasound measures.

INTRODUCTION: Nerve involvement in immune-related neuropathies is non-homogeneous, and therefore characterization of ultrasound (US) abnormalities is difficult. We developed two measures to quantify US abnormalities in immune-related neuropathies. METHODS: Intranerve cross-sectional area (CSA) variability for each nerve was calculated as: maximal CSA/minimal CSA. Internerve CSA variability for each patient was calculated as: maximal intranerve CSA variability/minimal intranerve CSA variability. Six patients underwent US evaluation of the median, ulnar, and fibular nerves, and the abnormalities were scored with our newly developed measures. RESULTS: The new measures were applicable to all nerves and patients. The highest degree of intra- and internerve CSA variability was observed in multifocal motor neuropathy, consistent with the asymmetric characteristics of this neuropathy. CONCLUSIONS: The application of intra- and internerve CSA variability measures allows us to quantify the heterogeneity of nerves and nerve segments and identify different US patterns in diverse immune-related neuropathies.

Intensive Care Unit-Acquired Weakness and Positioning-Related Peripheral Nerve Injuries in COVID-19: A Case Series of Three Patients and the Latest Literature Review.

A subgroup of COVID-19 patients requires intensive respiratory care. The prolonged immobilization and aggressive treatments predispose these patients to develop intensive care unit-acquired weakness (ICUAW). Furthermore, this condition could increase the chance of positioning-related peripheral nerve injuries. On the basis of the latest literature review, we describe a case series of three patients with COVID-19 who developed ICUAW complicated by positioning-related peripheral nerve injuries Every patient presented sensorimotor axonal polyneuropathy and concomitant myopathy in electrophysiological studies. Furthermore, muscle MRI helped the diagnosis of ICUAW, showing massive damage predominantly in the proximal muscles. Notably, nerve ultrasound detected positioning-related peripheral nerve injuries, even though the concomitant ICUAW substantially masked their clinical features. During the acute phase of severe COVID-19 infection, most medical attention tends to be assigned to critical care management, and neuromuscular complications such as ICUAW and positioning-related peripheral nerve injuries could be underestimated. Hence, when starting post-ICU care for COVID-19 cases, the combination of electrophysiological and imaging studies will aid appropriate evaluation on the patients with COVID-19-related ICUAW.

Personalized Clinical Phenotyping through Systems Medicine and Artificial Intelligence.

Personalized Medicine (PM) has shifted the traditional top-down approach to medicine based on the identification of single etiological factors to explain diseases, which was not suitable for explaining complex conditions. The concept of PM assumes several interpretations in the literature, with particular regards to Genetic and Genomic Medicine. Despite the fact that some disease-modifying genes affect disease expression and progression, many complex conditions cannot be understood through only this lens, especially when other lifestyle factors can play a crucial role (such as the environment, emotions, nutrition, etc.). Personalizing clinical phenotyping becomes a challenge when different pathophysiological mechanisms underlie the same manifestation. Brain disorders, cardiovascular and gastroenterological diseases can be paradigmatic examples. Experiences on the field of Fondazione Policlinico Gemelli in Rome (a research hospital recognized by the Italian Ministry of Health as national leader in "Personalized Medicine" and "Innovative Biomedical Technologies") could help understanding which techniques and tools are the most performing to develop potential clinical phenotypes personalization. The connection between practical experiences and scientific literature highlights how this potential can be reached towards Systems Medicine using Artificial Intelligence tools.

Ultrasound guidance increases diagnostic yield of needle EMG in plegic muscle.

OBJECTIVES: To increase the specificity of motor unit potential (MUPs) detection by using ultrasound guided electromyography (USG-EMG) in patients with muscle plegia due to traumatic nerve lesions. METHODS: Forty-six patients with recent nerve trauma underwent baseline standard EMG (ST-EMG) evaluation with evidence of absent MUPs. In 41 of them, ST-EMG was repeated after 2-3 months (T1) and the patients were accordingly divided in two groups: ST-EMG+ (if MUPs were detected) or ST-EMG- (MUPs not detected). Then, ST-EMG- patients underwent muscle ultrasound evaluation (M-US) and, if isles of muscular contractility were found, they also had USG-EMG. The same protocol was repeated 4-6 months after baseline (T2). RESULTS: At T1, 22/41 patients were ST-EMG+. While 19/41 were ST-EMG-; 9 of these patients had M-US consistent with residual muscular activity, for that reasons underwent USG-EMG with 7 of 9 demonstrating MUPs (at T2 all of these 7 patients resulted ST-EMG). In the other 2 patients, we found no MUPs at T1 but they became ST-EMG+ or USG-EMG positive at T2. The remaining 10 ST-EMG- patients had no EMG or US evidence of muscle contraction at T1, but at T2 2 of 10 became ST-EMG+ and 2 had USG-EMG showing MUPs. In the remaining 6 patients still M-US negative at T2, complete denervation was diagnosed. Concerning the 22 patients who were ST-EMG+ at T1, all but one showed increase of MUPs at T2. CONCLUSIONS: In this study, we demonstrated the utility of US guidance when performing EMG evaluation in locating isles of muscular contractility in patients who have no detectable MUPs on EMG after nerve trauma. SIGNIFICANCE: USG-EMG significantly increases the specificity of needle EMG allowing earlier detection of MUPs.

Cortical connectivity from EEG data in acute stroke: A study via graph theory as a potential biomarker for functional recovery.

Cerebral post-stroke plasticity has been repeatedly investigated via functional neuroimaging techniques mainly based on blood flow/metabolism. However, little is known on predictive value of topological properties of widely distributed neural networks immediately following stroke on rehabilitation outcome and post-stroke recovery measured by early functional outcome. The utility of EEG network parameters (i.e. small world organization) analysis as a potential rough and simple biomarker for stroke outcome has been little explored and needs more validation. A total of 139 consecutive patients within a post-stroke acute stage underwent EEG recording. A group of 110 age paired healthy subjects constituted the control group. All patients were clinically evaluated with 3 scales for stroke: NIHSS, Barthel and ARAT. As a first result, NIHSS, Barthel and ARAT correlated with Small World index as provided by the proportional increment/decrement of low (delta) and viceversa of high (beta2 and gamma) EEG frequency bands. Furthermore, in line with the aim of the present study, we found a strong correlation between NIHSS at follow up and gamma Small World index in the acute post-stroke period, giving SW index a significant weight of recovery prediction. This study aimed to investigate possible correlations between functional abnormalities of brain networks, measured by small world characteristics detected in resting state EEG source investigation, and early post-stroke clinical outcome in order to find a possible predictive index of functional recovery to address and/or correct the rehabilitation program.

Immediate effects of rhythmic auditory stimulation on gait kinematics in Parkinson's disease ON/OFF medication.

OBJECTIVE: Gait impairment is a highly disabling symptom for Parkinson's disease (PD) patients. Rhythmic auditory stimulation (RAS), has shown to improve spatio-temporal gait parameters in PD, but only a few studies have focused on their effects on gait kinematics, and the ideal stimulation frequency has still not been identified. METHODS: We enrolled 30 PD patients and 18 controls. Patients were evaluated under two conditions (with (ON), and without (OFF) medications) with three different RAS frequencies (90%, 100%, and 110% of the patient's preferred walking cadence). Spatial-temporal parameters, joint angles and gait phases distribution were evaluated. A novel global index (GPQI) was used to quantify the difference in gait phase distribution. RESULTS: Along with benefits in spatial-temporal parameters, GPQI improved significantly with RAS at a frequency of 110% for both ON and OFF medication conditions. In the most severe patients, the same result was observed also with RAS at 100%. CONCLUSIONS: RAS administration, at a frequency of 110% of the preferred walking frequency, can be beneficial in improving the gait pattern in PD patients. SIGNIFICANCE: When rhythmic auditory stimulation is provided to patients with PD, the selection of an adequate frequency of stimulation can optimize their effects on gait pattern.

Ultrasound Diagnosis of Postoperative Complications of Nerve Repair.

BACKGROUND: Peripheral nerve injuries often undergo surgical repair, but poor postoperative functional recovery is frequently observed. CASE DESCRIPTION: We describe 4 cases of traumatic nerve lesions in whom postoperative recovery was prevented by complications such as detachment of nerve sutures or neuroma growth. To the best of our knowledge, no similar cases have been reported in literature so far. It is important to obtain an early diagnosis of such condition because it prevents recovery and delays reintervention, which should be performed before complete muscle denervation and atrophy. CONCLUSION: Nerve ultrasound is a valuable tool in traumatic nerve injury and has proven to be useful in postoperative follow-up, especially in diagnosing surgical complications such as detachment of nerve direct sutures.