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The variety of sources of brachial plexus injuries (BPIs) and the severity and similarity of their clinical symptoms with those of other injuries make their differential diagnosis difficult. Enriching their diagnosis with objective high-sensitivity diagnostics such as clinical neurophysiology may lead to satisfactory treatment results, and magnetic stimulation (MEP) might be an advantageous addition to the diagnostic standard of electrical stimulation used in electroneurography (ENG). The asymptomatic side in BPI cases sometimes shows only subclinical neurological deficits; this study aimed to clarify the validity and utility of using MEP vs. ENG to detect neural conduction abnormalities. Twenty patients with a BPI and twenty healthy volunteers with matching demographic and anthropometric characteristics were stimulated at their Erb’s point in order to record the potentials evoked using magnetic and electrical stimuli to evaluate their peripheral motor neural transmission in their axillar, musculocutaneous, radial, and ulnar nerves. MEP was also used to verify the neural transmission in participants’ cervical roots following transvertebral stimulations, checking the compatibility and repeatability of the evoked potential recordings. The clinical assessment resulted in an average muscle strength of 3–1 (with a mean of 2.2), analgesia that mainly manifested in the C5–C7 spinal dermatomes, and a pain evaluation of 6–4 (mean of 5.4) on the symptomatic side using the Visual Analog Scale, with no pathological symptoms on the contralateral side. A comparison of the recorded potentials evoked with magnetic versus electrical stimuli revealed that the MEP amplitudes were usually higher, at p = 0.04–0.03, in most of the healthy volunteers’ recorded muscles than in those of the group of BPI patients, whose recordings showed that their CMAP and MEP amplitude values were lower on their more symptomatic than asymptomatic sides, at p = 0.04–0.009. In recordings following musculocutaneous and radial nerve electrical stimulation and ulnar nerve magnetic stimulation at Erb’s point, the values of the latencies were also longer on the patient’s asymptomatic side compared to those in the control group. The above outcomes prove the mixed axonal and demyelination natures of brachial plexus injuries. They indicate that different types of traumatic BPIs also involve the clinically asymptomatic side. Cases with predominantly median nerve lesions were detected in sensory nerve conduction studies (SNCSs). In 16 patients, electromyography revealed neurogenic damage to the deltoid and biceps muscles, with an active denervation process at work. The predominance of C5 and C6 brachial plexus injuries in the cervical root and upper/middle trunk of patients with BPI has been confirmed. A probable explanation for the bilateral symptoms of dysfunction detected via clinical neurophysiology methods in the examined BPI patients, who showed primarily unilateral damage, maybe the reaction of their internal neural spinal center’s organization. Even when subclinical, this may explain the poor BPI treatment outcomes that sometimes occur following long-term physical therapy or surgical treatment.

The clinical neurophysiological tests allow us to determine the type, extent, and nature of brachial plexus damage. They are crucial in decision making regarding surgical procedures or conservative treatment. This report aimed to present an algorithm for rehabilitation procedures in patients with brachial plexus injury of various origins based on the results of neurophysiology findings for the selection of procedures supporting the process of nerve and muscle regeneration. The research group consisted of patients whose medical documentation was analysed concerning the reason, level, and localization of damage to the brachial plexus structures, surgical and or rehabilitative treatment, as well as the MRI results. Among the group of fourteen patients, the clinical studies showed the greatest incidence of brachial plexus injuries of the mixed (both pre- and postganglionic), all trunks, and cervical root injuries, respectively. Results of the motor evoked potentials (MEP) and electroneurography (ENG) recordings induced at levels of spinal roots and Erb’s point showed a decrease of more than 40% in amplitudes on the symptomatic side in comparison to the asymptomatic side. This diffeence was recorded for the axillary and radial innervation and the C5, C6, and C7 root domains, ranging from 57% to 66%; the lowest decrease was recorded following electrical stimulation at Erb’s point for the ulnar nerve (34%). The latency prolongation on the symptomatic side in CMAP and MEP tests ranged from 0.2 to 1.7 ms, with the most following magnetic stimulation of the C5 cervical root for the axillary innervation. Most of the results indicated the axonotmesis and neuropraxia type of injury in motor fibers (40%) confirmed by EMG results. The sensory conduction studies (SNCS) in distal nerve branches did not confirm the severe advancement of the brachial plexus injury (63%). The proposed algorithm of the physiotherapeutic procedures should be mainly targeted for recovery of motor dysfunction as the consequence of brachial plexus injury. Rehabilitation should incorporate the treatment supporting nerve regeneration, muscle strengthening, and maintaining functional ranges of motion of the injured extremities. The rehabilitation treatment for patients with brachial plexus injuries is an individualised process, and the selection of procedures and the effectiveness of the treatment undertaken should be confronted with results of neurophysiological tests verifying the motor neural transmission from the level of the cervical motor centre to the effector, peripheral nerve function, and muscle’s motor unit activity.

The anatomical complexity of brachial plexus injury requires specialized in-depth diagnostics. The clinical examination should include clinical neurophysiology tests, especially with reference to the proximal part, with innovative devices used as sources of precise functional diagnostics. However, the principles and clinical usefulness of this technique are not fully described. The aim of this study was to reinvestigate the clinical usefulness of motor evoked potential (MEP) induced by a magnetic field applied over the vertebrae and at Erb’s point to assess the neural transmission of brachial plexus motor fibers. Seventy-five volunteer subjects were randomly chosen to participate in the research. The clinical studies included an evaluation of the upper extremity sensory perception in dermatomes C5–C8 based on von Frey’s tactile monofilament method, and proximal and distal muscle strength by Lovett’s scale. Finally, 42 healthy people met the inclusion criteria. Magnetic and electrical stimuli were applied to assess the motor function of the peripheral nerves of the upper extremity and magnetic stimulus was applied to study the neural transmission from the C5–C8 spinal roots. The parameters of compound muscle action potential (CMAP) recorded during electroneurography and MEP induced by magnetic stimulation were analyzed. Because the conduction parameters for the groups of women and men were comparable, the final statistical analysis covered 84 tests. The parameters of the potentials generated by electrical stimulus were comparable to those of the potentials induced by magnetic impulse at Erb’s point. The amplitude of the CMAP was significantly higher following electrical stimulation than that of the MEP following magnetic stimulation for all the examined nerves, in the range of 3–7%. The differences in the potential latency values evaluated in CMAP and MEP did not exceed 5%. The results show a significantly higher amplitude of potentials after stimulation of the cervical roots compared to potentials evoked at Erb’s point (C5, C6 level). At the C8 level, the amplitude was lower than the potentials evoked at Erb’s point, varying in the range of 9–16%. We conclude that magnetic field stimulation enables the recording of the supramaximal potential, similar to that evoked by an electric impulse, which is a novel result. Both types of excitation can be used interchangeably during an examination, which is essential for clinical application. Magnetic stimulation was painless in comparison with electrical stimulation according to the results of a pain visual analog scale (3 vs. 5.5 on average). MEP studies with advanced sensor technology allow evaluation of the proximal part of the peripheral motor pathway (between the cervical root level and Erb’s point, and via trunks of the brachial plexus to the target muscles) following the application of stimulus over the vertebrae.

Temporary occlusion of the common cervical artery is the reason for ischemic stroke in 25% of patients. Little data is provided on its effects, especially regarding neurophysiological studies verifying the neural efferent transmission within fibers of the corticospinal tract in experimental conditions. Studies were performed on 42 male Wistar rats. In 10 rats, ischemic stroke was evoked by permanent occlusion of the right carotid artery (group A); in 11 rats, by its permanent bilateral occlusion (B); in 10 rats, by unilateral occlusion and releasing after 5 min (C); and in 11 rats, by bilateral occlusion and releasing after 5 min (D). Efferent transmission of the corticospinal tract was verified by motor evoked potential (MEP) recordings from the sciatic nerve after transcranial magnetic stimulation. MEPs amplitude and latency parameters, oral measurements of temperature, and verification of ischemic effects in brain slides stained with hematoxylin and eosin staining (H + E) were analyzed. In all groups of animals, the results showed that five minutes of uni- or bilateral occlusion of the common carotid artery led to alterations in brain blood circulation and evoked changes in MEP amplitude (by 23.2% on average) and latency parameters (by 0.7 ms on average), reflecting the partial inability of tract fibers to transmit neural impulses. These abnormalities were associated with a significant drop in the body temperature by 1.5 °C on average. Ten minutes occlusion in animals from groups A and B resulted in an MEP amplitude decrease by 41.6%, latency increase by 0.9 ms, and temperature decrease by 2.9 °C of the initial value. In animals from groups C and D, five minutes of recovery of arterial blood flow evoked stabilization of the MEP amplitude by 23.4%, latency by 0.5 ms, and temperature by 0.8 °C of the initial value. In histological studies, the results showed that ischemia was most prominent bilaterally in sensory and motor areas, mainly for the forelimb, rather than the hindlimb, innervation of the cortex, putamen and caudate nuclei, globulus pallidus, and areas adjacent to the fornix of the third ventricle. We found that the MEP amplitude parameter is more sensitive than the latency and temperature variability in monitoring the ischemia effects course following common carotid artery infarction, although all parameters are correlated with each other. Temporary five-minute lasting occlusion of common carotid arteries does not evoke total and permanent inhibition in the activity of corticospinal tract neurons in experimental conditions. The symptoms of rat brain infarction are much more optimistic than those described in patients after stroke, and require further comparison with the clinical observations.

Introduction. Benign tumour surgery of the parotid gland may cause iatrogenic injury of the facial nerve, with results of postoperative treatment depending on the type of injury. The study aimed to clarify the mechanism of facial nerve injury after benign tumour surgery of parotid gland. Materials and Methods. The effectiveness was verified preoperatively and 1, 3, 6 and 17 months postoperatively. House-Brackmann scales, electroneurography, blink reflex study and needle electromyography were performed. Pharmacological treatment (Galantamine, Cocarboxylase, Dexamethasone, Triamcinolone) and supervised physiotherapeutic procedures (Facial-Oral-Tract-Therapy, Proprioceptive neuromuscular facilitation) were applied for six months. Results. Tumour removal led to the total paralysis of the left facial nerve, IV, III and III House-Brackmann grades were ascertained at the subsequent 3rd–5th periods of observation. In postoperative studies, electroneurography results showed full functional recovery of the frontal branch and incomplete regeneration in the marginal mandibular branch. Blink reflex examination showed proper parameters of evoked potentials only during preoperative and the last observation period. Residual voluntary activity of the frontal muscle and weak voluntary activity of orbicularis oris muscle were recorded in the needle electromyography examination. Contracture of mimic muscles at rest and improvement of their voluntary activity on the left side was observed six months after surgery compared to the early period of observation. Conclusion. Consecutive studies showed the predominant axonal type of injury in the marginal mandibular branch and neuropraxia effect of the facial nerve, allowing the creation of a rehabilitation programme optimal for the functional recovery of the nerve.

Despite the high availability of surface electromyography (sEMG), it is not widely used for testing the effectiveness of exercises that activate intrinsic muscles of foot in people with hallux valgus. The aim of this study was to assess the effect of the toe-spread-out (TSO) exercise on the outcomes of sEMG recorded from the abductor hallucis muscle (AbdH). An additional objective was the assessment of nerve conduction in electroneurography. The study involved 21 patients with a diagnosed hallux valgus (research group A) and 20 people without the deformation (research group B) who performed a TSO exercise and were examined twice: before and after therapy. The statistical analysis showed significant differences in the third, most important phase of TSO. After the exercises, the frequency of motor units recruitment increased in both groups. There were no significant differences in electroneurography outcomes between the two examinations in both research groups. The TSO exercise helps in the better activation of the AbdH muscle and contributes to the recruitment of a larger number of motor units of this muscle. The TSO exercises did not cause changes in nerve conduction. The sEMG and ENG are good methods for assessing this exercise but a comprehensive assessment should include other tests as well.

Introduction. Sympathetic skin response (SSR) is applied in evaluation of dysfunctions in autonomic nervous system. Among others, electrical and sound stimuli are most frequently used to evoke SSR. Aim. The aim of this study was to determine if the bell ring stimulus with parameters different from standard sound stimulation evokes similar reactions in autonomic system as electrical stimulus with defined parameters. Material and methods. SSR parameters were recorded following simultaneous sound and electrical stimulation. Twenty young volunteers (aged 23 ± 2.1 years) were examined once with SSR and R-R interval variation (RRIV) tests in order to confirm lack of functional changes in autonomic nervous system. Results. Values of mean amplitudes of SSR were always higher during recordings from upper limbs than the lower ones irrespective of the three types of applied stimuli. Mean values of latencies were comparable when SSR were induced with acoustic, electrical and both stimuli during recordings performed from upper and lower extremities. Bell ring stimulus influenced only mean values of SSR area recorded both from upper (p ? 0.011) and lower (p ? 0.023) extremities. Heart beats variability in RRIV recordings changed at 13.5% which is comparable to results obtained by other authors. Conclusions. Results indicate that the application of different modalities stimuli evokes SSR with comparable parameters. Each of them can be used for objective evaluation of the sympathetic nervous system function. Both SSR and RRIV tests evaluating the function of two effector types should be applied for the diagnosis of the probable dysautonomia in patients who show unclear clinical symptoms.

Introduction. Dermatomal somatosensory evoked potentials (DSEP) are used to assess the function of afferent pathway following electrical stimulation of the skin around selected dermatomes of single spinal roots. Aim. The aim of the study was to characterize the parameters of DSEP latencies for assessment of L5 and S1 nerve root transmission in healthy people taking into account the important diagnostic difference between the right and left side and the impact of height, age and sex on values of DSEP latencies. Material and methods. DSEP tests were performed in the control group of 30 healthy volunteers and in the patients with low back pain radiating to one of the lower extremities for comparison. Disc-root conflict was confirmed in MRI studies. Clinical examination included assessment of muscles strength innervated from the L5 and S1 roots and the sensory perception from L5 and S1 dermatomes. In all patients straight leg raising (SLR) and Schober's tests have been performed. To assess the severity of pain, the visual analogue scale (VAS) was used. The clinical and neurophysiological evaluation of patients was performed before and after 4 weeks of the physiotherapeutic exercises selected for this study. Results. Results indicated statistically significant relationship between the DSEP N33, P40, N50 components latencies and the height. The gender and age did not affect DSEP latencies. Values of DSEP latencies in the first and second periods of observations were normal and no sensory and motor disturbances have been observed in patients. DSEP test showed the high conformity with the results of clinical studies. Conclusions. DSEP diagnostic determines well the subjective sensation changes in patients suffering from low back pain. Kinesiotherapy treatment of patients with low back pain without neurological deficits seems to be the appropriate therapeutic method.