The influence of surface EMG-triggered multichannel electrical stimulation on sensomotoric recovery in patients with lumbar disc herniation: study protocol for a randomized controlled trial (RECO).

BACKGROUND: Intervertebral disc degeneration is one of the most common reasons for chronic low back pain and sensomotoric deficits, often treated by lumbar sequestrectomy. Nevertheless, the prognostic factors relevant for time and quality of recovery, of the surgical procedure, relative to conservative treatment, remain controversial and require further investigation. Surface electrical stimulation (SES) may be an influential intervention, already showing positive impact on motor and sensory recovery in different patient groups. Since mechanisms of SES still remain unclear, further inquiry is needed. METHODS/DESIGN: This is a prospective, monocentric, randomized, controlled clinical trial. A total of 80 adult patients suffering from a lumbar disc herniation (LDH; 40 treated surgically, 40 conservatively) are allocated in a ratio of 1:1. Patients in the treatment group will receive surface electromyography (EMG)-triggered electrical stimulation for eight weeks, whereas patients in the control group will not obtain any additional treatment. The primary outcome parameter is defined as the cold detection threshold (CDT), determined by quantitative sensory testing (QST), 24 months after intervention. Secondary outcome parameters include the inquiry of sensory nerve function by two-point discrimination and QST, the assessment of motor nerve function by manual muscle testing, and validated scales and scores. These include: the Oswestry Disability Index (ODI) and the Core Outcome Measures Index (COMI) assessing the domains pain, back-specific function, work disability, and patient satisfaction; the EQ-5D investigating the patient's generic health status; the painDETECT questionnaire (PD-Q) to identify neuropathic pain components; and the Beck Depression Inventory (BDI) to assess severity of depression. Moreover, neurological status, pain medication usage, and blood samples (CRP, TNFα, IL-1ß, IL-6) will be evaluated. Study data generation (study site) and data storage, processing, and statistical analysis are clearly separated. DISCUSSION: The results of the RECO study will detect the effect of EMG-triggered multichannel SES on the improvement of mechanical and thermal sensitivity and the effect on motor recovery and pain, associated with clinical and laboratory parameters. Furthermore, data comparing surgical and conservative treatment can be collected. This will hopefully allow treatment recommendations for patients with LDH accompanied by a sensomotoric deficit. TRIAL REGISTRATION: ISRCTN, ISRCTN12741173 . Registered on 15 January 2017.

Effects of ethyl chloride spray on pain and parameters of needle electromyography in the upper extremity.

OBJECTIVE: The aim of this study was to compare the effects of ethyl chloride and placebo sprays for reducing pain induced by needle electromyography and changes in parameters of the motor unit action potential during needle electromyography of the upper extremity. DESIGN: Sixty patients were randomized into the ethyl chloride or placebo spray groups. In both groups, spray was applied just before needle electromyography of the flexor carpi radialis, and a visual analog scale to evaluate the pain of needle electromyography and a five-point Likert scale for patient satisfaction and preference for reexamination were compared between the two groups. Then, changes in the amplitude, phases, turns, and duration of the motor unit action potential during needle electromyography of the biceps brachii were compared before and after spraying in each group. RESULTS: The visual analog scale was significantly lower, and patient satisfaction and preference for reexamination were significantly higher in the ethyl chloride spray group. Among the parameters of the motor unit action potential, there were no significant changes except for an increased duration after spraying with ethyl chloride. CONCLUSIONS: Ethyl chloride spray can effectively reduce pain, but it must be used with caution because it may affect parameters of the motor unit action potential during needle electromyography.

Listening to music during electromyography does not influence the examinee's anxiety and pain levels.

INTRODUCTION: Listening to music is a low-cost intervention that has demonstrated ability to reduce pain and anxiety levels in various medical procedures. METHODS: Subjects undergoing electrophysiological examinations were randomized into a music-listening group and a control group. Visual analog scales were used to measure anxiety and pain levels during the procedure. RESULTS: Thirty subjects were randomized to each group. No statistically significant difference was found in anxiety or pain levels during the procedure between groups. However, most subjects in the music-listening group reported anxiety and pain reduction and would prefer to hear music in a future examination. CONCLUSIONS: Although listening to music during electrophysiological examinations did not reduce anxiety or pain significantly, most subjects felt a positive effect and would prefer to hear music; therefore, we suggest that music may be offered optionally in the electromyography laboratory setting.

Comparison of the effects of vapocoolant spray and topical anesthetic cream on pain during needle electromyography in the medial gastrocnemius.

OBJECTIVE: To compare the effects of a vapocoolant spray and an eutectic mixture of local anesthetics (EMLA) cream in reducing pain during needle electromyography examination. DESIGN: Randomized controlled trial. SETTING: Physical medicine and rehabilitation department of a university hospital. PARTICIPANTS: Adults who underwent needle electromyography (N=99) were randomized to 1 of 2 experimental groups or the control group. Two patients dropped out during the study. INTERVENTIONS: In the experimental groups, vapocoolant spray or EMLA cream were applied before needle electromyography. In the control group, needle electromyography was performed without pretreatment. MAIN OUTCOME MEASURES: Intensity of pain associated with needle electromyography was assessed using a 100-mm visual analog scale (VAS). Patient satisfaction and preference for repeated use were measured using a 5-point Likert scale. RESULTS: VAS score for pain intensity was significantly lower in the spray group (31.9; 95% confidence interval [CI], 22.0-41.7) compared with the control group (52.9; 95% CI, 45.9-60.0; P=.002), whereas there was no significant difference between the EMLA cream group (42.4; 95% CI, 34.2-50.7) and the control group. Patient satisfaction and preference for repeated use were higher in the spray group than the EMLA group. CONCLUSIONS: Vapocoolant spray was more effective than EMLA cream in reducing pain during needle electromyography.

The feasibility of hypnotic analgesia in ameliorating pain and anxiety among adults undergoing needle electromyography.

OBJECTIVE: Our hypothesis was that hypnotic analgesia reduces pain and anxiety during electromyography (EMG). DESIGN: We performed a prospective randomized, controlled clinical trial at outpatient electrodiagnostic clinics in teaching hospitals. Just before EMG, 26 subjects were randomized to one of three 20-min audio programs: education about EMG (EDU) (n = 8); hypnotic induction without analgesic suggestion (n = 10); or hypnotic induction with analgesic suggestion (n = 8). The blinded electromyographer provided a posthypnotic suggestion at the start of EMG. After EMG, subjects rated worst and average pain and anxiety using visual analog scales. RESULTS: Mean values for the EDU, hypnotic induction without analgesic suggestion, and hypnotic induction with analgesic suggestion groups were not significantly different (mean +/- SD): worst pain 67 +/- 25, 42 +/- 18, and 49 +/- 30; average pain 35 +/- 26, 27 +/- 14, and 25 +/- 22; and anxiety 44 +/- 41, 42 +/- 23, and 22 +/- 24. When hypnosis groups were merged (n = 18) and compared with the EDU condition (n = 8), average and worst pain and anxiety were less for the hypnosis group than EDU, but this was statistically significant only for worst pain (hypnosis, 46 +/- 24 vs. EDU, 67 +/- 35; P = 0.049) with a 31% average reduction. CONCLUSIONS: A short hypnotic induction seems to reduce worst pain during electromyography.

Intramuscular versus surface electromyography of the diaphragm for determining neuromuscular blockade.

We determined the neuromuscular blockade of 0.2 mg. kg(-1) mivacurium at the diaphragm by using two new methods of electromyographic (EMG) monitoring and compared it with acceleromyography of the orbicularis oculi (OO) and the corrugator supercilii (CS) muscle. After the induction of anesthesia in 15 patients undergoing gynecologic laparoscopic surgery, evoked EMG responses at the diaphragm were obtained by using skin electrodes at the back of the patient, placed lateral to T12/L1 or L1/L2, and a laparoscopically applied wire electrode inserted into the dorsolateral portion of the diaphragm. Acceleromyography at the right OO and the left CS was performed. The facial and phrenic nerves were stimulated transcutaneously (onset: every 10 s, offset: every 15 s, single twitch stimulation). Lag and onset time, peak effect, and clinical duration (time to reach 75% of control value and time to reach 90% of control value) were measured and the results were compared by using analysis of variance; P < 0.05 showed significant difference. Pearson's correlation test and the Bland-Altman test were used to compare the two diaphragmatic monitoring methods. Mean peak effects of >98% were reached at all sites. Onset times at diaphragm (skin, IM) were significantly (P < 0.005) shorter than at the CS or OO (100 +/- 14 s and 98 +/- 16 s vs 147 +/- 39 s, 185 +/- 38 s) without being statistically different between OO and CS. There was a good correlation of lag, onset time, time to reach 75% of control value, and time to reach 90% of control value (r = 0.8, 0.9, 0.8, and 0.75; P < 0.01) between the two diaphragmatic methods. Mean difference and limits of agreements are -2 +/- 15 s, 1 +/- 21 s, -1 +/- 2.3 min, and -2 +/- 3.4 min. We showed a shorter onset and clinical duration at the diaphragm in comparison with CS and OO. Two methods of EMG of the diaphragm correlated well and showed good comparability. The novel method of surface diaphragmatic EMG at the patient's back may be useful during routine clinical anesthesia.