Standard neurophysiological studies and motor evoked potentials in evaluation of traumatic brachial plexus injuries – A brief review of the literature

Purpose Traumatic damage to the brachial plexus is associated with temporary or permanent motor and sensory dysfunction of the upper extremity. It may lead to the severe disability of the patient, often excluded from the daily life activity. The pathomechanism of brachial plexus injury usually results from damage detected in structures taking origin in the rupture, stretching or cervical roots avulsion from the spinal cord. Often the complexity of traumatic brachial plexus injury requires a multidisciplinary diagnostic process including clinical evaluation supplemented with clinical neurophysiology methods assessing the functional state of its structures. Their presentation is the primary goal of this paper. Methods The basis for the diagnosis of brachial plexus function is a clinical examination and neurophysiology studies: electroneurography (ENG), needle electromyography (EMG), somatosensory evoked potentials (SEPs) and motor evoked potentials (MEPs) assessing the function of individual brachial plexus elements. Conclusions The ENG and EMG studies clarify the level of brachial plexus damage, its type and severity, mainly using the Seddon clinical classification. In contrast to F-wave studies, the use of the MEPs in the evaluation of traumatic brachial plexus injury provides valuable information about the function of its proximal part. MEPs study may be an additional diagnostic in confirming the location and extent of the lesion, considering the pathomechanism of the damage. Clinical neurophysiology studies are the basis for determining the appropriate therapeutic program, including choice of conservative or reconstructive surgery which results are verified in prospective studies

Meniscus suture provides better clinical and biomechanical results at 1-year follow-up than meniscectomy

BACKGROUND: Surgery of meniscus tear results in limitation of function. The aim of study was functional assessment of knee 1 year after surgery with two techniques in cases of the medial meniscus tear followed by the same supervised rehabilitation. MATERIALS AND METHODS: A total of 30 patients with good KOSS scores constituted two equal groups after partial meniscectomy or meniscus suture. Measurements of knee extensors and flexors muscles peak torques were performed with angular velocities 60, 180, 240 and 300 s(−1) using Biodex IV system. One-leg-hop and one-leg-rising tests ascertained the function of operated knee. Results of examinations were compared with reference to healthy volunteers. Results of biomechanical and clinical studies were correlated to create complex and objective method evaluating treatment. RESULTS: Extensors peak torque values at 60 s(−1) angular velocity and H/Q coefficient were decreased after meniscectomy more than meniscus suture in comparison to healthy volunteers (P ≤ 0.001; P ≤ 0.05). Analysis of functional tests revealed that patients after meniscectomy showed difference between operated and non-operated knee (P ≤ 0.01) while patients with meniscus suture differed the least to controls (P ≤ 0.05). Extensors peak torque values at 60 s(−1) angular velocity correlated with results of one-leg-rising test. CONCLUSION: Results suggest worse functional effects when meniscectomy is applied which implies modification of the rehabilitative methods in a postoperative period

Update on the diagnostic clinical neurophysiology for rheumatology

The current concepts on the clinical neurophysiology examinations for the differential diagnosis of rheumatic diseases are presented. The review aims to provide experience and practical guidelines, especially regarding electromyography. More needle than surface electromyography examinations at muscle rest or during its maximal contraction may reveal the characteristic effects of the myogenic injury caused by particular rheumatic diseases. The diagnosis of myopathic disorders, often found in rheumatic diseases is difficult because of the frequent vasculitis coexistence in the patients evoking subsequent changes in nerve fibres leading to degenerative neurogenic changes that may overlap the diagnostic picture of the primary myogenic changes caused by rheumatic diseases. In these cases, the neurophysiological studies of efferent and afferent neural transmission often reveal peripheral neuropathies just at the subclinical level

The Role of Peripheral Nerve Electrotherapy in Functional Recovery of Muscle Motor Units in Patients after Incomplete Spinal Cord Injury

Functional electrical nerve stimulation (FES) is a non-invasive technique for neuromodulation and may have the potential for motor rehabilitation following incomplete spinal cord injury (iSCI). Axonal degeneration in motor fibers of lower extremity nerves is an inevitable secondary pathological change in iSCI subjects, despite no direct damage to lumbosacral neuromeres. This study evaluated the role of FES with individual parameters based on results of comparative neurophysiological studies. Forty-two participants with C4 to Th12 iSCI received repetitive sessions of electrostimulations applied to peroneal and tibial motor fibers, performed five times a week from 6 to 14 months, and the uniform system of kinesiotherapeutic treatment. The average duration of one electrostimulation session was 17 min, stimulation frequency of a train 20–70 Hz, duration of 2–3 s, intervals 2–3 s, pulses intensity 18–45 mA. The algorithm change was based on objective tests of subsequent surface electromyography (sEMG), and electroneurography (ENG) recordings. The same neurophysiological studies were also performed in patients after C2-Th12 iSCI treated with kinesiotherapy only (K group, N = 25) and compared with patients treated with both kinesiotherapy and electrostimulation (K + E, N = 42). The study revealed improvements in sEMG parameters recorded from tibialis anterior, gastrocnemius, extensor digitorum brevis muscles, and ENG evoked a compound muscle action potential recorded following bilateral stimulation of more peroneal than tibial nerves. Neurophysiological recordings had significantly better parameters in the K + E group of patients after therapy but not in the K group patients. The improvement of the motor transmission peripherally may reflect the specific neuromodulatory effect of FES algorithm evaluated with sEMG and ENG. FES may inhibit degeneration of axons and support functional recovery after iSCI

The Role of Transcranial Magnetic Stimulation, Peripheral Electrotherapy, and Neurophysiology Tests for Managing Incomplete Spinal Cord Injury

Efforts to find therapeutic methods that support spinal cord functional regeneration continue to be desirable. Natural recovery is limited, so high hopes are being placed on neuromodulation methods which promote neuroplasticity, such as repetitive transcranial magnetic stimulation (rTMS) and electrical stimulation used as treatment options for managing incomplete spinal cord injury (iSCI) apart from kinesiotherapy. However, there is still no agreement on the methodology and algorithms for treatment with these methods. The search for effective therapy is also hampered by the use of different, often subjective in nature, evaluation methods and difficulties in assessing the actual results of the therapy versus the phenomenon of spontaneous spinal cord regeneration. In this study, an analysis was performed on the database of five trials, and the cumulative data are presented. Participants (iSCI patients) were divided into five groups on the basis of the treatment they had received: rTMS and kinesiotherapy (N = 36), peripheral electrotherapy and kinesiotherapy (N = 65), kinesiotherapy alone (N = 55), rTMS only (N = 34), and peripheral electrotherapy mainly (N = 53). We present changes in amplitudes and frequencies of the motor units’ action potentials recorded by surface electromyography (sEMG) from the tibialis anterior—the index muscle for the lower extremity and the percentage of improvement in sEMG results before and after the applied therapies. The increase in values in sEMG parameters represents the better ability of motor units to recruit and, thus, improvement of neural efferent transmission. Our results indicate that peripheral electrotherapy provides a higher percentage of neurophysiological improvement than rTMS; however, the use of any of these additional stimulation methods (rTMS or peripheral electrotherapy) provided better results than the use of kinesiotherapy alone. The best improvement of tibialis anterior motor units’ activity in iSCI patients provided the application of electrotherapy conjoined with kinesiotherapy and rTMS conjoined with kinesiotherapy. We also undertook a review of the current literature to identify and summarise available works which address the use of rTMS or peripheral electrotherapy as neuromodulation treatment options in patients after iSCI. Our goal is to encourage other clinicians to implement both types of stimulation into the neurorehabilitation program for subjects after iSCI and evaluate their effectiveness with neurophysiological tests such as sEMG so further results and algorithms can be compared across studies. Facilitating the motor rehabilitation process by combining two rehabilitation procedures together was confirmed

Changes in muscle activity determine progression of clinical symptoms in patients with chronic spine-related muscle pain. A complex clinical and neurophysiological approach

Spine-related muscle pain can affect muscle strength and motor unit activity. This study was undertaken to investigate whether surface electromyographic (sEMG) recordings performed during relaxation and maximal contraction reveal differences in the activity of muscles with or without trigger points (TRPs). We also analyzed the possible coexistence of characteristic spontaneous activity in needle electromyographic (eEMG) recordings with the presence of TRPs. Thirty patients with non-specific cervical and back pain were evaluated using clinical, neuroimaging and electroneurographic examinations. Muscle pain was measured using a visual analog scale (VAS), and strength using Lovett’s scale; trigger points were detected by palpation. EMG was used to examine motor unit activity. Trigger points were found mainly in the trapezius muscles in thirteen patients. Their presence was accompanied by increased pain intensity, decreased muscle strength, increased resting sEMG amplitude, and decreased sEMG amplitude during muscle contraction. eEMG revealed characteristic asynchronous discharges in TRPs. The results of EMG examinations point to a complexity of muscle pain that depends on progression of the myofascial syndrom

Neurophysiological Evaluation of the Functional State of Muscular and Nervous Systems in High-Maneuvering Jet Fighters

The present study aimed to assess the function of muscular and nervous systems in high-maneuvering jet fighters with the chosen method of clinical neurophysiology, which methodologically has not yet been presented in detail. Fifteen pilots with the experience of more than 1700 flying hours at 7G overloading on average and fifteen healthy subjects for the comparison of health status declared to participate in this study. The dermatomal perception from C4 to S1 was examined using von Frey’s filaments tactile method. Surface electromyography (sEMG) recordings examined the activity of proximal and distal muscles in the upper and lower extremities, the transmission of motor nerve impulses peripherally was diagnosed by electroneurography (ENG), the efferent transmission from C5–C7 and L4–L5 spinal centers to muscles was entirely verified with recordings of motor-evoked potentials induced oververtebrally with the magnetic field (MEP). The pilots estimated more lumbosacral than cervical pain at about 2 on the 10-point visual analog scale (VAS). Sensory perception studies did not reveal abnormal symptoms in the C2–S1 dermatomes innervation. Clinical neurophysiology studies indicated, in general, the lack of pathology during sEMG tests in comparison to healthy subjects or even better muscle motor unit contractile properties in pilots, both in the upper and lower extremities. In pilots, the parameters of ENG and MEP examinations show a statistically significant sensitivity for detecting the slight changes and their consequences in the transmission of neural impulses within L4–L5 ventral root fibers. The research results enable specifying the algorithm of future preventing rehabilitative treatment in high-maneuvering jet fighters with an average flight experience of 2000 h and working conditions at 7G on average. This study, for the first time, describes the application of a set of diagnostic neurophysiological methods with the particular importance of MEPs in the clinical evaluation of the jet fighters’ health status

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

Post-Stroke Treatment with Neuromuscular Functional Electrostimulation of Antagonistic Muscles and Kinesiotherapy Evaluated with Electromyography and Clinical Studies in a Two-Month Follow-Up

The aim of this study was to determine the sustained influence of personalized neuromuscular functional electrical stimulation (NMFES) combined with kinesiotherapy (mainly, proprioceptive neuromuscular facilitation (PNF)) on the activity of muscle motor units acting antagonistically at the wrist and the ankle in a large population of post-stroke patients. Clinical evaluations of spasticity (Ashworth scale), manual muscle testing (Lovett scale), and surface electromyography recordings at rest (rEMG) and during attempts of maximal muscle contraction (mcEMG) were performed three times in 120 post-stroke patients (T0: up to 7 days after the incidence; T1: after 21 days of treatment; T2: after 60 days of treatment). Patients (N = 120) were divided into two subgroups—60 patients received personalized NMFES and PNF treatment (NMFES+K), and the other 60 received only PNF (K). The NMFES+K therapy resulted in a decrease in spasticity and an increase in muscle strength of mainly flexor muscles, in comparison with the K group. A positive correlation between the increase of rEMG amplitudes and high Ashworth scale scores and a positive correlation between low amplitudes of mcEMG and low Lovett scale scores were found in the wrist flexors and calf muscles on the paretic side. Negative correlations were found between the rEMG and mcEMG amplitudes in the recordings. The five-grade alternate activity score of the antagonists’ actions improved in the NMFES+K group. These improvements in the results of controlled NMFES treatment combined with PNF in patients having experienced an ischemic stroke, in comparison to the use of kinesiotherapy alone, might justify the application of conjoined rehabilitation procedures based on neurophysiological approaches. Considering the results of clinical and neurophysiological studies, we suppose that NMFES of the antagonistic muscle groups acting at the wrist and the ankle may evoke its positive effects in post-stroke patients by the modulation of the activity more in the spinal motor centers, including the level of Ia inhibitory neurons, than only at the muscular level