Influence of surface peripheral electrical stimulation on nerve regeneration after digital nerve neurorrhaphy: study protocol for a randomized clinical trial

We will study the influence of low intensity and frequency surface peripheral electrical stimulation (PES) on nerve regeneration of digital nerve injuries of the hand after its surgical repair in humans. Participants will be patients with acute traumatic peripheral nerve injury referred to the Hand Surgery Service of the General Hospital of the State of Bahia, a reference service in the state. These patients will undergo surgery followed by PES in the immediate postoperative period. After hospital discharge, they will be followed up on an outpatient basis by researchers, who will remotely supervise a physiotherapy program. Our hypothesis is that PES will positively influence the recovery of sensory function in patients undergoing neurorrhaphy of digital nerves of the hand. ReBEC registration: U1111-1259-1998 (12/18/2020)

Peripheral Electrical Stimulation Modulates Cortical Beta-Band Activity

Low-frequency peripheral electrical stimulation using a matrix electrode (PEMS) modulates spinal nociceptive pathways. However, the effects of this intervention on cortical oscillatory activity have not been assessed yet. The aim of this study was to investigate the effects of low-frequency PEMS (4 Hz) on cortical oscillatory activity in different brain states in healthy pain-free participants. In experiment 1, PEMS was compared to sham stimulation. In experiment 2, motor imagery (MI) was used to modulate the sensorimotor brain state. PEMS was applied either during MI-induced oscillatory desynchronization (concurrent PEMS) or after MI (delayed PEMS) in a cross-over design. For both experiments, PEMS was applied on the left forearm and resting-state electroencephalography (EEG) was recording before and after each stimulation condition. Experiment 1 showed a significant decrease of global resting-state beta power after PEMS compared to sham (p = 0.016), with a median change from baseline of −16% for PEMS and −0.54% for sham. A cluster-based permutation test showed a significant difference in resting-state beta power comparing pre- and post-PEMS (p = 0.018) that was most pronounced over bilateral central and left frontal sensors. Experiment 2 did not identify a significant difference in the change from baseline of global EEG power for concurrent PEMS compared to delayed PEMS. Two cluster-based permutation tests suggested that frontal beta power may be increased following both concurrent and delayed PEMS. This study provides novel evidence for supraspinal effects of low-frequency PEMS and an initial indication that the presence of a cognitive task such as MI may influence the effects of PEMS on beta activity. Chronic pain has been associated with changes in beta activity, in particular an increase of beta power in frontal regions. Thus, brain state-dependent PEMS may offer a novel approach to the treatment of chronic pain. However, further studies are warranted to investigate optimal stimulation conditions to achieve a reduction of pain.

Influence of surface peripheral electrical stimulation on nerve regeneration after digital nerve neurorrhaphy: study protocol for a randomized clinical trial

We will study the influence of low intensity and frequency surface peripheral electrical stimulation (PES) on nerve regeneration of digital nerve injuries of the hand after its surgical repair in humans. Participants will be patients with acute traumatic peripheral nerve injury referred to the Hand Surgery Service of the General Hospital of the State of Bahia, a reference service in the state. These patients will undergo surgery followed by PES in the immediate postoperative period. After hospital discharge, they will be followed up on an outpatient basis by researchers, who will remotely supervise a physiotherapy program. Our hypothesis is that PES will positively influence the recovery of sensory function in patients undergoing neurorrhaphy of digital nerves of the hand. ReBEC registration: U1111-1259-1998 (12/18/2020)

The immediate effect of transcranial direct current stimulation combined with peripheral electrical stimulation in the control of temporomandibular pain in subjects with sickle cell disease: A protocol for one session randomized, crossover, double-blind clinical trial

INTRODUCTION: Temporomandibular disorder (TMD) is currently considered a central sensitization syndrome that belongs to the orofacial nociplastic pain group and offers great challenges for clinical practice. It can also be identified in individuals with sickle cell disease. Neuromodulation is a promising therapy that can help individuals with refractory chronic pain. To our knowledge, there is no treatment proposal for these individuals with chronic orofacial pain resulting from sickle cell disease. OBJECTIVE: This is a protocol of a randomized, double-blind, cross-over clinical trial. The purpose of this protocol is to investigate whether the immediate effect of transcranial direct current stimulation can be increased by adding the effect of peripheral sensory electrical stimulation. METHODS: Twenty women between 18 and 49 years of age will be screened to participate in this cross-over study where they will all receive the three types of protocol with a one-week washout. Active transcranial Direct Current Stimulation (tDCS) + active Peripheral Electrical Stimulation (PES); Active tDCS + PES sham and tDCS sham + PES sham. Stimulation with tDCS will be at 2 mA anodic over the motor cortex for 20 minutes ipsilateral to the most painful temporomandibular joint (TMJ). Peripheral electrical stimulation will be at 100 Hz over the most painful TMJ masseter muscle for 30 min. OUTCOME: The main outcome will be pain intensity assessed by VAS scale and by a pressure algometer in grams. In addition, endogenous pain modulation will be analyzed through the temporal summation of pain with Aesthesio precision tactile sensory filaments and conditioned pain modulation (CPM) evaluated by an algometer and thermal conditioned stimulus, as secondary outcomes. Data will be analyzed using ANOVA of repeated measures, controlling for confounding variables.

Peripheral electrical stimulation to reduce pathological tremor: a review

Interventions to reduce tremor in essential tremor (ET) and Parkinson’s disease (PD) clinical populations often utilize pharmacological or surgical therapies. However, there can be significant side effects, decline in effectiveness over time, or clinical contraindications for these interventions. Therefore, alternative approaches must be considered and developed. Some non-pharmacological strategies include assistive devices, orthoses and mechanical loading of the tremorgenic limb, while others propose peripheral electrical stimulation. Specifically, peripheral electrical stimulation encompasses strategies that activate motor and sensory pathways to evoke muscle contractions and impact sensorimotor function. Numerous studies report the efficacy of peripheral electrical stimulation to alter tremor generation, thereby opening new perspectives for both short- and long-term tremor reduction. Therefore, it is timely to explore this promising modality in a comprehensive review. In this review, we analyzed 27 studies that reported the use of peripheral electrical stimulation to reduce tremor and discuss various considerations regarding peripheral electrical stimulation: the stimulation strategies and parameters, electrodes, experimental designs, results, and mechanisms hypothesized to reduce tremor. From our review, we identified a high degree of disparity across studies with regard to stimulation patterns, experimental designs and methods of assessing tremor. Having standardized experimental methodology is a critical step in the field and is needed in order to accurately compare results across studies. With this review, we explore peripheral electrical stimulation as an intervention for tremor reduction, identify the limitations and benefits of the current state-of-the-art studies, and provide ideas to guide the development of novel approaches based on the neural circuitries and mechanical properties implied in tremor generation.

Searching for the optimal Transcranial Direct Current Stimulation (TDCS) target combined with peripheral electrical stimulation in chronic low back pain: a protocol for a randomized controlled trial

Backgroud: Low back pain (LBP) has been associated with severe impairments, primarily related to activities of daily living, functional ability and quality of life. A multimodal approach to pain management, such as transcranial direct current stimulation (tDCS) and peripheral electrical stimulation (PES), may improve outcomes in chronic LBP. However, the optimal cerebral target for stimulation still remains controversial. This pilot trial aims to investigate whether active stimulation could promote additional gains to the PES results in LBP patients. Our secondary objective is to investigate whether the stimulation of primary motor cortex and dorsolateral prefrontal cortex results in distinct clinical effects for the patients involved. Methods: Sixty patients with chronic low back pain will be randomized into one of three tDCS groups associated with PES: motor primary cortex, dorsolateral prefrontal cortex and sham stimulation. Each group will receive transcranial direct current stimulation at an intensity of 2 mA for 30 minutes daily for 10 consecutive days. Patients will be assessed with a Brief Pain Inventory (BPI), Roland Morris Disability Questionnaire (RMDQ), Medical Outcomes Study 36-item Short - Form Health Survey (SF-36) and electromyography at baseline, endpoint (after 10 sessions) and 1-month follow up. Discussion: This study will help to clarify the additive effects of tDCS combined with peripheral electrical stimulation on pain relief, muscle function and improvement in quality of life. Additionally, we will provide data to identify optimal targets for management of chronic low back pain.

Peripheral electrical stimulation augments cerebral collateral circulation if performed within a critical time window

Ischemic stroke is one of the leading causes of death and disability in the world. Recent advances in acute stroke care have dramatically improved clinicians’ abilities to reperfuse occluded blood vessels. With these advances, the importance of adjunctive therapies to supplement or complement reperfusion therapy is receiving greater interest. Cerebral collateral circulation is one of such area that is now gaining greater interest in acute stroke care. In this study, we investigate the use of peripheral electrical stimulation to induce functional hyperemia in a mouse animal model in the setting of acute stroke. Using a laser speckle contrast imaging system, we evaluated the use of peripheral electrical stimulation at 1 hour and 3 hours after stroke induction. Results demonstrated that stimulation initiated 1 hour following stroke significantly increase collateral cerebral blood flow, while stimulation at 3 hours after stroke had no appreciable effect. These results suggest that augmentation cerebral collateral circulation may be possible in the setting of acute stroke although there may be a critical time window in which this would have to be initiated.