The effect of attentional focusing strategies on EMG-based classification.

Earlier studies showed that external focusing enhances motor performance and reduces muscular activity compare to internal one. However, low activity is not always desired especially in case of Human-Machine Interface applications. This study is based on investigating the effects of attentional focusing preferences on EMG based control systems. For the EMG measurements via biceps brachii muscles, 35 subjects were asked to perform weight-lifting under control, external and internal focus conditions. The difference between external and internal focusing was found to be significant and internal focus enabled higher EMG activity. Besides, six statistical features, namely, RMS, maximum, minimum, mean, standard deviation, and variance were extracted from both time and frequency domains to be used as inputs for Artificial Neural Network classifiers. The results found to be 87.54% for ANN1 and 82.69% for ANN2, respectively. These findings showed that one's focus of attention would be predicted during the performance and unlike the literature, internal focusing could be also useful when it is used as an input for HMI studies. Therefore, attentional focusing might be an important strategy not only for performance improvement to human movement but also for advancing the study of EMG-based control mechanisms.

Postoperative Analgesic Efficacy of the Ultrasound-Guided Erector Spinae Plane Block in Patients Undergoing Lumbar Spinal Decompression Surgery: A Randomized Controlled Study.

BACKGROUND: Spinal surgery is a procedure that causes intense and severe pain in the postoperative period. Erector spinae plane (ESP) block can target the dorsal-ventral rami of thoracolumbar nerves, but its effect on lumbar surgery is unclear. The aim of this study was to investigate the effect of the ESP block on postoperative opioid consumption and pain scores in patients undergoing spinal surgery. METHODS: Sixty patients undergoing open lumbar decompression surgery were randomly assigned to 2 groups. The ESP Group (n = 30) received ultrasound-guided bilateral ESP block with 0.25% bupivacaine 20 mL. In the Control Group (n = 30), no intervention was performed. Postoperative analgesia was performed intravenously twice a day with 400 mg ibuprofen and patient-controlled analgesia with tramadol. Postoperative visual analogue scale scores, opioid consumption, rescue analgesia, and opioid-related side effects were evaluated. RESULTS: Compared with the Control Group, the visual analogue scale scores were statistically lower in the ESP Group during all measurements of time, both at rest and active movement (P < 0.05). Tramadol consumption was lower in the ESP Group compared with the Control Group at all time periods (P < 0.05). Twenty-four hour tramadol consumption in the Control Group was significantly higher compared with the ESP Group (370.33 ± 73.27 mg and 268.33 ± 71.44 mg; P < 0.001, respectively) and the difference was 28%, and time to first analgesic requirement was significantly longer in the ESP Group than in the Control Group. CONCLUSIONS: ESP block can be used in multimodal analgesia practice to reduce opioid consumption and relieve acute postoperative pain in patients undergoing open lumbar decompression surgery.