We present a low‐frequency stimulation method via multi‐pad electrodes for delaying muscle fatigue. We compared two protocols for muscle activation of the quadriceps in paraplegics. One protocol ...involved a large cathode at 30 HZ (HPR, high pulse‐rate), and the other involved four smaller cathodes at 16 HZ (LPR, low pulse‐rate). The treatment included 30‐min daily sessions for 20 days. One leg was treated with the HPR protocol and the other with the LPR protocol. Knee‐joint torque was measured before and after therapy to assess the time interval before the knee‐joint torque decreased to 70% of the initial value. The HPR therapy provided greater increases in muscle endurance and force in prolonged training. Yet the LPR stimulation produced less muscle fatigue compared to the HPR stimulation. The results suggest that HPR is the favored protocol for training, and LPR is better suited for prolonged stimulation. Muscle Nerve, 2010
Objective:
To investigate the effectiveness of neuromuscular electrical stimulation added to pulmonary rehabilitation on walking tolerance and balance in patients with chronic obstructive pulmonary ...disease (COPD).
Design:
Randomized clinical trial.
Setting:
Outpatient, Faculty of Medicine of Sousse, Tunisia.
Subjects:
A total of 45 patients with COPD were assigned to an intervention group (n = 25) or a control group (n = 20).
Interventions:
The intervention group underwent a neuromuscular electrical stimulation added to pulmonary rehabilitation, and the control group underwent only a pulmonary rehabilitation, three times per week during six months.
Main Measures:
Measures were taken at baseline and after six months of training. A stabilometric platform, time up and go, Berg balance scale tests, 6 minute walking test, and the maximal voluntary contraction were measured.
Results:
In the intervention group, an increase in an exercise tolerance manifested by a longer distance walked in 6 minute walking test 619.5 (39.6) m was observed in comparison to the control group 576.3 (31.5) m. The values of the time up and go, Berg balance scale, and maximal voluntary contraction in the intervention group at follow-up were significantly higher than those in the control group (P = 0.02, P = 0.01, P = 0.0002, respectively). The center of pressure in the mediolateral and in the anteroposterior directions, as well as the center of pressure area was significantly more improved in open eyes and closed eyes in the intervention group compared to the control group (P < 0.001).
Conclusion:
The neuromuscular electrical stimulation added to pulmonary rehabilitation group benefited from better walking tolerance and greater balance improvement than the only pulmonary rehabilitation.
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Recapitulation of in vivo environments that drive muscle cells to organize into a physiologically relevant 3D architecture remains a major challenge for muscle tissue engineering. To ...recreate electrophysiology of muscle tissues, electroactive biomaterials have been used to stimulate muscle cells with exogenous electrical fields. In particular, the use of electroactive biomaterials with an anisotropic micro-/nanostructure that closely mimic the native skeletal-muscle extracellular matrix (ECM) is desirable for skeletal muscle tissue engineering. Herein, we present a hierarchically organized, anisotropic, and conductive Polycaprolactone/gold (PCL/Au) scaffold for guiding myoblasts alignment and promoting the elongation and maturation of myotubes under electrical stimulation. Culturing with H9c2 myoblasts cells indicated that the nanotopographic cues was crucial for nuclei alignment, while the presence of microscale grooves effectively enhanced both the formation and elongation of myotubes. The anisotropic structure also leads to anisotropic conductivity. Under electrical stimulation, the elongation and maturation of myotubes were significantly enhanced along the anisotropic scaffold. Specifically, compared to the unstimulated group (0 V), the myotube area percentage increased by 1.4, 1.9 and 2.4 times in the 1 V, 2 V, 3 V groups, respectively. In addition, the myotube average length in the 1 V group increased by 1.3 times compared to that of the unstimulated group, and significantly increased by 1.8 and 2.0 times in the 2 V, 3 V groups, respectively. Impressively, the longest myotubes reached more than 4 mm in both 2 V and 3 V groups. Overall, our conductive, anisotropic 3D nano/microfibrous scaffolds with the application of electrical stimulation provides a desirable platform for skeletal muscle tissue engineering.
Objective
Gynecological malignant tumor patients with hypertension, even if blood pressure is well controlled, are prone to hypertension before surgery. We plan to verify the effect of transcutaneous ...electrical acupoint stimulation (TEAS) on stabilizing blood pressure before operation.
Methods
We enrolled 91 patients and randomly divided them into TEAS group (n=46) and control group (n=45). Patients in TEAS group received TEAS at acupoints Hegu and Neiguan. Patients in control group received transcutaneous electrical stimulation at the nonacupoint position of the upper limbs. After entering the operating room, the blood pressure before and after induction was measured. The main results were the occurrence of preinduction hypertension and postinduction hypotension.
Results
There was no difference in the general information of the two groups. There were four cases (9%) of preinduction hypertension in TEAS group and 13 cases (29%) in control group. The incidence in TEAS group was significantly lower (P=0.013). There were five cases (11%) of postinduction hypotension in TEAS group and eight cases (18%) in control group. There was no significant difference between the two groups (P=0.346). The systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean blood pressure (MBP) of the highest blood pressure before induction in TEAS group were lower than those in control group (P=0.002, 0.002, and 0.001). There was no difference in SBP, DBP, or MBP between the two groups on the day before the operation. There was no difference in the lowest blood pressure before operation between the two groups after induction
Conclusion
TEAS can prevent preinduction hypertension in patients with gynecological malignant tumors.
Clinical Trial Registration
http://www.chictr.org.cn/showproj.aspx?proj=143276
, identifier ChiCTR2100054336.
Electrical stimulation (ES) induces wound healing and skin regeneration. Combining ES with the tissue-engineering approach, which relies on biomaterials to construct a replacement tissue graft, could ...offer a self-stimulated scaffold to heal skin-wounds without using potentially toxic growth factors and exogenous cells. Unfortunately, current ES technologies are either ineffective (external stimulations) or unsafe (implanted electrical devices using toxic batteries). Hence, we propose a novel wound-healing strategy that integrates ES with tissue engineering techniques by utilizing a biodegradable self-charged piezoelectric PLLA (Poly (l-lactic acid)) nanofiber matrix. This unique, safe, and stable piezoelectric scaffold can be activated by an external ultrasound (US) to produce well-controlled surface-charges with different polarities, thus serving multiple functions to suppress bacterial growth (negative surface charge) and promote skin regeneration (positive surface charge) at the same time. We demonstrate that the scaffold activated by low intensity/low frequency US can facilitate the proliferation of fibroblast/epithelial cells, enhance expression of genes (collagen I, III, and fibronectin) typical for the wound healing process, and suppress the growth of S. aureus and P. aeruginosa bacteria in vitro simultaneously. This approach induces rapid skin regeneration in a critical-sized skin wound mouse model in vivo. The piezoelectric PLLA skin scaffold thus assumes the role of a multi-tasking, biodegradable, battery-free electrical stimulator which is important for skin-wound healing and bacterial infection prevention simultaneuosly.
Incidence of non-union following long bone fracture fixation and spinal fusion procedures is increasing, and very costly for patients and the medical system. Direct current (DC) electrical ...stimulation has shown success as an adjunct therapy to stimulate bone healing and increase surgery success rates, though drawbacks of current devices and implantable battery packs have limited widespread use. Energy harvesting utilising piezoelectric materials has been widely studied for powering devices without a battery, and a preclinical animal study has shown efficacy of a piezocomposite spinal fusion implant resulting in faster, more robust fusion. Most piezoelectric energy harvesters operate most effectively at high frequencies, limiting power generation from loads experienced by orthopaedic implants during human motion. This work characterises the efficient power generation capability of a novel composite piezoelectric material under simulated walking loads. Building on compliant layer adaptive composite stacks (CLACS), the power generation of mixed-mode CLACS (MMCLACS) is defined. Utilising poling direction to capitalise on in-plane strain generation due to compliant layer expansion, MMCLACS significantly increased power output compared to a standard piezo stack. The combination of radial and through-thickness poled piezoelectric elements within a stack to create MMCLACS significantly increases power generation under low-frequency dynamic loads. This technology can be adapted to a variety of architectures and assembled as a load-bearing energy harvester within current implants. MMCLACS integrated with implants would provide enough power to deliver bone healing electrical stimulation directly to the fusion site, decreasing non-union rates, and also could provide quantitative assessment of healing progression through load sensing.
To explore the effect of non-invasive neurostimulation therapies on dysphagia patients after stroke.
We searched MEDLINE (Ovid), PubMed, Embase, Web of Science, ScienceDirect, and Cochrane library ...databases until April 22, 2020. All published and unpublished randomized controlled trials (RCT) were included. Full texts were independently reviewed. The risk of RCT bias was evaluated by two independent assessors using the Cochrane risk of bias tool. The primary outcome measure was swallowing function before and after neurostimulation therapy. The effect sizes are calculated from the extracted data and combined into a comprehensive summary statistic.
A total of 27 randomized controlled trials were included in this study, involving 914 stroke patients (27 intervention groups and 20 control groups). Meta-analysis showed that compared with the control group, noninvasive neurostimulation therapies (repetitive transcranial magnetic stimulation (rTMS), transcranial direct current stimulation (tDCS), surface neuromuscular electrical stimulation (sNMES) or pharyngeal electrical stimulation (PES)) had a better effect (SMD = 0.91; 95% CI: 0.54–1.27; Z = 4.84; P < 0.00001; I² = 86%). In the subgroup analysis based on type of stimulus, rTMS appeared to perform better. In the subgroup analysis based on clinical phase, stimulation applied in the acute phase may be more effective. In the subgroup analysis based on the site of injury, the brainstem injury group seemed to achieve better outcomes. In the subgroup analysis based on stroke type, the cerebral infarction group had better outcomes than the cerebral infarction/hemorrhage mixed group.
Non-invasive neurostimulation therapies can effectively promote the recovery of dysphagia after stroke.
Two multi-contact epineural electrodes were placed around radial and median nerves of two subjects with high tetraplegia C4, American Spinal Injury Association Impairment Scale (AIS) A, group 0 of ...the International Classification for Surgery of the Hand in Tetraplegia. The purpose was to study the safety and capability of these electrodes to generate synergistic motor activation and functional movements and to test control interfaces that allow subjects to trigger pre-programmed stimulation sequences. The device consists of a pair of neural cuff electrodes and percutaneous cables with two extracorporeal connection cables inserted during a surgical procedure and maintained for 28 days. Continuity tests of the electrodes, selectivity of movements induced, motor capacities for grasping and gripping, conformity of the control order, tolerance, and acceptability were assessed. Neither of the two participants showed general and local comorbidity. Acceptability was optimal. None of the stimulation configurations generated contradictory movements. The success rate in task execution by the electro-stimulated hand exceeded the target of 50% (54% and 51% for patients 1 and 2, respectively). The compliance rate of the control orders in both patients was >90% using motion inertial measurement unit (IMU)-based detection and 100% using electromyography (EMG)-based detection in patient 1. These results support the relevance of neural stimulation of the tetraplegic upper limb with a more selective approach, using multi-contact epineural electrodes with nine and six contact points for the median and radial nerve respectively.
The delivery of a nerve insult (a “conditioning lesion”) prior to a subsequent test lesion increases the number of regenerating axons and accelerates the speed of regeneration from the test site. A ...major barrier to clinical translation is the lack of an ethically acceptable and clinically feasible method of conditioning that does not further damage the nerve. Conditioning electrical stimulation (CES), a non-injurious intervention, has previously been shown to improve neurite outgrowth in vitro. In this study, we examined whether CES upregulates regeneration-associated gene (RAG) expression and promotes nerve regeneration in vivo, similar to a traditional nerve crush conditioning lesion (CCL). Adult rats were divided into four cohorts based on conditioning treatment to the common peroneal (fibular) nerve: i) CES (1h, 20Hz); ii) CCL (10s crush); iii) sham CES (1h, 0Hz); or iv) naïve (unconditioned). Immunofluorescence and qRT-PCR revealed significant RAG upregulation in the dorsal root ganglia of both CES and CCL animals, evident at 3–14days post-conditioning. To mimic a clinical microsurgical nerve repair, all cohorts underwent a common peroneal nerve cut and coaptation one week following conditioning. Both CES and CCL animals increased the length of nerve regeneration (3.8-fold) as well as the total number of regenerating axons (2.2-fold), compared to the sham and naïve-conditioned animals (p<0.001). These data support CES as a non-injurious conditioning paradigm that is comparable to a traditional CCL and is therefore a novel means to potentially enhance peripheral nerve repair in the clinical setting.
•Conditioning electrical stimulation of uninjured nerves upregulates regeneration-associated gene expression•Conditioning electrical stimulation accelerates nerve regeneration similar to conditioning crush lesions•Electrical nerve stimulation may be a clinically acceptable conditioning method prior to nerve transfer repairs
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