Electromyography and clinical neurophysiology最新文献

Carpal tunnel syndrome (CTS) is the most common focal compression neuropathy. There are a significant number of different methods available to evaluate a patient for median nerve compromise at the carpal tunnel. One of them is interpolation method created by Dr E.B. Bodofski. In our study Sensitivity of interpolation method was 85.5%, Specificity was 85%, Positive predictive value was 94.6% and Negative predictive value was 65.4%. These results are lower than Dr Bodofski results. Also in our study sensitivity of midpalm antidromic sensory method was 95.1%, Specificity was 95%, Positive predictive value was 98.3% and Negative predictive value was 86.4%, these results are higher than results of interpolation method. These show interpolation method is a good method (with high sensitivity & specificity) for diagnosis of mild CTS, but it's sensitivity & specificity are lower than antideromic sensory stimulation method at wrist & midpalm.

Background: A standard treatment option for carpal tunnel syndrome (CTS) is local injection of anesthetic-corticosteroid. This clinical trial was designed to compare the safety and efficacy of daily application of the EMLA cream (lidocaine 2.5% plus prilocaine 2.5%) with that of a single injection of methyl prednisolone acetate (Depo-Medrol) 40 mg.

Methods: In this randomized, parallel-group, open-label, single-center, case-controlled, prospective study, 65 participants (70 hands) aged 18-75 years with clinical & electrodiagnostic evidences of CTS were randomized to receive either the EMLA cream (n = 30 patients, 35 hands, group 1) or one injection of methylprednisolone acetate 40 mg at wrist (n = 35 patients, group 2). Outcome assessments included the visual analog scale and clinical assessment.

Results: After 4 weeks of treatment, patients in both groups reported significant changes (P < 0.001) in pain intensity. Both treatments were well tolerated, with treatment-related adverse events (AEs) reported in 2 patients in group 1 (5.7%) and 10 patients in group 2 (28.5%) No systemic treatment-related AEs were observed with the EMLA cream.

Conclusion: EMLA cream was effective in reducing pain associated with CTS and well tolerated and it may offer patients with CTS an effective, noninvasive symptomatic treatment.

The objective of this study was to compare the efficiency of pedaling (EP) and the electromyographic activity (EMG) between cyclists and non-cyclists during cycling in different cadences. Using a cyclosimulator, 12 cyclists (26.5 +/- 4.5 years; 68.2 +/- 10.5 kg; 175.6 +/- 8.2 cm) and 9 non-cyclists (25.1 +/- 4.3 years; 72.6 +/- 9.8 kg; 174.6 +/- 6.2 cm), performed a maximum incremental test (ITmax), and subsequently, two constant load tests (Tconst) in different cadences (60 and 90 rpm) at the intensity of the electromyographic fatigue threshold (EMGth) determined in ITmax. Before the Tconst, the subjects performed a maximum isometric voluntary contraction (MIVC) for the normalization of the EMG data of Tconst. During Tconst, the EMG of the studied muscles was recorded, as well as the EP Although there was a trend of higher values in all occasions for the cyclists, there were no statistical differences in EP and the EMG when compared in a same cadence between groups. However, when the EMG is compared in different cadences in the same group, there was a significant increase (p < 0.05) in the muscles that work during the recovery phase with the increase in cadence, in both groups, being more evident in the cyclists. In conclusion, the hypothesis that cyclists had better technique than non-cyclists was not confirmed statistically. However, it was found that the increase in cadence improves the EP and the recruitment in both groups.

Spinal modulation of motoneuron excitability has been extensively investigated during various tasks in humans. Previous studies have revealed that balance tasks induce a decrease in Ia-motoneuron communication which has been attributed to increased levels of presynaptic inhibition (PI). Moreover, this depression in Ia-motoneuron connectivity takes place subsequent to the elevation of muscle activity. Therefore, it is hypothesized that motor learning has inhibitory effects on the spinal mechanisms in spite of the increased muscle activity during a motor task. The purpose of this study was to explore the effects of a complex balance task on the H-reflex. Soleus H-reflexes were measured from 11 healthy adult subjects both before and after 20 minutes of a complex balance task. A commonly reported H-reflex conditioning technique was applied in order to measure changes in spinal PI: an electrical volley to the heteronymous Ia (common peroneal nerve conditioning, CPN). Subjects stood on a custom designed balance board and performed a continuous series of plantar and dorsiflexion. To ensure that the task was performed similarly between subjects, auditory cues for movement were given by a metronome with a frequency of 1 Hz. The initial amplitude of the unconditioned soleus H-reflex was set at 50% of H-max, and unconditioned and conditioned (PI) reflexes were recorded before, during, and after the balance task. The unconditioned soleus H-reflex was significantly decreased 59% after the balance task and PI was increased by 50%. Further, during a period of rest following the task (20 minutes) the unconditioned H-reflex returned to near baseline levels whereas the PI conditioned H-reflex was not altered The results suggest that the initial depression in motoneuron excitability immediately after the balance task is accompanied by an increase in PI, but also that the recovery of the depressed H-reflex after the task appears to be independent of PI.

Purpose: The aim of this study was to verify the effect of HVES on pain and electromyographic activity of the masticatory muscles in TMD patients, as well as assess the effect of this treatment on the severity of TMD.

Methods: Participated in this study 12 women with TMD that underwent electromyographic exam of the masticatory muscles, and responded to the FAI, RDC/TMD and VAS.

Results: After treatment, by the VAS a significant reduction in the intensity of pain it was verified; in the EMG that at rest and during isometric contraction of the mandibular depressor muscles there was a significant reduction in the RMS values; in voluntary contraction during maximal intercuspidation, a significant increase was observed in the values of RMS for the MD and ME muscles.

Conclusion: HVES reduced the severity of TMD and the intensity of pain, and made the masticatory muscles approach their normal electromyographic pattern.

We report a case of thrombotic occlusion of the left common iliac artery during an L5-S1 anterior interbody fusion exposed via a retroperitoneal approach. The loss of distal blood flow was detected by loss of cortical and peripheral somatosensory evoked potentials on the left lower extremity. Restoration of the blood flow resulted in gradual return of evoked potentials of the involved extremity. The neurophysiological and pulse oximetry monitoring of the lower extremities are extremely sensitive for an early detection of thrombotic occlusions and vascular complications.

This study compared the tibialis anterior (TA) surface electromyographic (sEMG) to force relationship for males and females. One-hundred participants (50 males and 50 females) performed three isometric contractions at 20, 40, 60, 80, and 100% of maximal voluntary contraction (MVC) in an apparatus designed to isolate the action of the dorsiflexors. The sEMG signal was amplified (1000x), band-pass filtered (10-500 Hz), and sampled at 2048 Hz. The load cell signal was low-pass filtered at 100 Hz and sampled at the same rate. Males were stronger than females (p < 0.05). However, there was no significant difference in the root-mean-square (RMS) amplitude of the sEMG signal between males and females (p < 0.05). Both groups exhibited a quadratic increase in the RMS across force levels (p < 0.05). The mean power frequency (MNF) of the sEMG signal for males was greater than for females (p < 0.05). Males and females exhibited a linear increase in MNF means up to 80% of MVC (p < 0.05). Between 80 and 100% MVC, the frequency values for the females plateaued while males showed a decrease (p < 0.05). The magnitude of the difference in MNF between males and females was consistent with the observation that males have greater type II muscle fiber diameters. In general, the pattern of means for RMS and MNF between males and females revealed no differences between groups in the sEMG-force relationship. We therefore conclude that there are no differences between males and females in the gradation of muscle force.

Background: Neurologic changes in visceral leishmaniasis are rarely reported. Some articles have reported symptoms suggestive of peripheral neuropathy and showed some degree of axonal degeneration and demyelination. The main purpose of the present study was to identify and quantitatively evaluate sympathetic dysfunction in VL.

Method: Twenty patients with visceral leishmaniasis and 20 healthy controls were studied. All the patients and controls were examined at first and skin sympathetic response was measured in all of the patients and control group by standard protocol.

Results: The patients had mean age of 24.2 +/- 17.8 months. The SSR to the electrical stimulus was absent in 10 patients with VL. In four patients all responses were present and, in four patients only one response from hand or foot was present and, in two cases responses were present from both hands. For right median nerve, median latency was 2.4 (min: 1.19, max: 6.92) seconds.

Conclusion: In conclusion impairment of SSR was demonstrated electrophysiologically in the patients with visceral leishmaniasis.

This report describes a case of a now 20-year-old young lady with a severe spinal cord injury (SCI) at cervical 5/6 levels (ASIA A), in whom a repair of some spinal cord functions could be achieved within 3 years of optimal coordination dynamics therapy (CDT). Magnetic Resonance Imaging (MRI) showed a destruction of almost 95% of the cross-sectional area at the injury levels. The 5% (if at all) spared cord tissue most likely consisted of only sensory tracts, since no motor functions were preserved below the level of injury. A near-complete recovery of the important vegetative functions urinary bladder control, respiration, and vasomotor tone could be achieved. Her motor and sensory functions also improved to some extent, and she is off all medications. However, her motor recovery was limited and she is still wheel-chair-dependent. There is functional and structural (MRI) evidence that the human spinal cord regenerates upon CDT. The movement-based learning therapy included the training of supported crawling, up-righting, walking, running, jumping, balance training, and exercising on special CDT devices. The regeneration of the spinal cord started after more than one year of CDT, it was very limited but continuous, and gave rise to substantial functional recovery. The recovery induced by regeneration upon CDT was quantified in terms of transient increases of coordination dynamics values, the improvement of motor programs as assessed by surface electromyography (sEMG), the improvement of movement performances, and the increase of the spinal cord matter at the injury site, quantified by MRI. The similarity between the improvement at cellular and integrative (network) level during this regeneration and development is analyzed with respect to 'walking'. Comparing the effort, required to achieve substantial improvement in this case of severe cervical SCI (with 95% cord destruction; 5% spared tissue) with the effort required in the case of partial cervical SCI (50% destruction; 50% spared tissue), IT is noted that the 95% injury is 10 times more intractable. It is inferred that in severe SCI, the repair crucially depends on the percentage of the spared tissue (tracts fibres and neuronal networks) at the injury site. Improper handling of the patient therefore, as false transport or too late relief of spinal cord compression, may give rise to further mechanical damage of the cord tissue for which a later administered intensive cCDT cannot compensate for.

Electrophysiologic studies have an important role in the diagnosis of lumbosacral radiculopathies. Electrophysiologic methods which are used conventionally are needle electromyography (EMG), late responses (F wave and H reflex), and nerve conduction studies. Somatosensory evoked potentials (SEPs) are also important complementary diagnostic methods in the electrophysiologic evaluation of lumbosacral radiculopathies. In this study, we aimed to determine whether SEPs have an advantage over the conventional electrophysiologic methods or whether sensory nerve stimulated SEPs over mixed nerve stimulated ones or the lumbar recordings over the scalp recordings in diagnosing lumbosacral radiculopathies. For this reason, the study included 20 patients with unilateral and unilevel S1 radiculopathy due to intervertebral disc herniation confirmed by clinical examination and magnetic resonance imaging (MRI) as the patient group. And a control group of 18 healthy subjects were also included in the study. Nerve conduction studies, late responses and scalp and lumbar-recorded SEPs after sural and posterior tibial nerve stimulation were studied in both groups, while needle EMG was performed only in the patient group. Patients who manifested abnormal findings on needle EMG or on late responses also showed abnormal findings on at least one type of the SEPs. SEPs detected abnormalities in 5 patients (25%) in whom needle EMG or late responses did not suggest any abnormality. In this study we concluded that SEPs may provide diagnostic information beyond conventional electrodiagnostic methods and that lumbar-recorded SEPs may have an advantage over scalp-recorded ones and sensory nerve stimulated SEPs over mixed nerve stimulated ones.