Electrical Stimulation Cycling Research Articles

Early Cyclical Neuromuscular Electrical Stimulation Improves Strength and Trophism by Akt Pathway Signaling in Partially Paralyzed Biceps Muscle After Spinal Cord Injury in Rats.

Electrical stimulation is often used to treat weakness in people with spinal cord injury (SCI); however its efficacy for increasing strength and trophism is weak, and the mechanisms underlying the therapeutic benefits are unknown. The purpose of this study was to analyze the effects of neuromuscular electrical stimulation (NMES) on muscle function, trophism, and the Akt pathway signaling involved in muscular plasticity after incomplete SCI in rats. This was an experimental study. Twenty-one adult female Wistar rats were divided into sham, SCI, and SCI plus NMES groups. In injured animals, SCI hemisection was induced by a surgical procedure at the C5-C7 level. The 5-week NMES protocol consisted of biceps brachii muscle stimulation 5 times per week, initiated 48 h after injury. Forepaw function and strength, biceps muscle trophism, and the expression of phosphorylated Akt, p70S6K, and GSK-3ß cellular anabolic pathway markers in stimulated muscle tissue were assessed. There was an increase in bicep muscle strength in the NMES group compared with the untreated SCI group, from postoperative day 21 until the end of the evaluation period. Also, there was an increase in muscle trophism in the NMES group compared with the SCI group. Forelimb function gradually recovered in both the SCI group and the NMES group, with no differences between them. Regarding muscle protein expression, the NMES group had higher values for phospho-Akt, phospho-p70S6K, and phospho-GSK-3ß than did the SCI group. The experimental findings were limited to an animal model of incomplete SCI and may not be fully generalizable to humans. Early cyclical NMES therapy was shown to increase muscle strength and induce hypertrophy after incomplete SCI in a rat model, probably by increasing phospho-Akt, phospho-p70S6K, and phospho-GSK-3ß signaling protein synthesis.

Training Effects and Safety of Functional Electrical Stimulation (FES) Cycling in People With Multiple Sclerosis

Training Effects and Safety of Functional Electrical Stimulation (FES) Cycling in People With Multiple Sclerosis

Functional electrical stimulation as a component of activity-based restorative therapy may preserve function in persons with multiple sclerosis

ObjectiveTo examine the effect of functional electrical stimulation (FES) cycling on disability progression in persons with multiple sclerosis (MS).DesignRetrospective cohort, 40 participants with mean follow-up of 15 months.SettingInternational Center for Spinal Cord Injury at Kennedy Krieger Institute in Baltimore, a rehabilitation referral center.ParticipantsForty consecutive persons with MS undergoing rehabilitation from 2007 to 2011, with at least two evaluations based on the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI).InterventionsFES cycling as part of activity-based restorative therapy interventions.Outcome measuresChange in Expanded Disability Status Scale (EDSS) and ISNCSCI motor, light touch, and pin prick scores from baseline to latest evaluation.ResultsIn 71% of patients, activity-based rehabilitation included FES cycling. There was no disability progression on the EDSS. Lower extremity motor scores improved or stabilized in 75% of patients with primary progressive MS (PPMS), 71.4% with secondary progressive MS (SPMS), and 54.5% with relapsing remitting MS (RRMS). Among patients with improved or stabilized lower extremity motor function, PPMS recorded a mean 9% improvement, SPMS 3% and RRMS 6%. In PPMS, use of FES showed trend towards improvement in motor scores (P = 0.070).ConclusionsFES as part of activity-based rehabilitation may help preserve or improve neurological function in patients with MS.

Effect of electrical stimulation to long head of biceps in reducing gleno humeral subluxation after stroke

Glenohumeral subluxation is the most frequent complication in post stroke hemiplegia and its reduction has been considered an important goal. Though it has been demonstrated that cyclical electrical stimulation of posterior deltoid and supraspinatus muscles can reduce subluxation, the role of biceps has not been given due consideration. The purpose of this study was to determine whether electrical stimulation to the long head of biceps could more effectively reduce gleno humeral subluxation. 24 patients were selected and consecutively assigned to group 1 (electrical stimulation to supraspinatus & posterior deltoid) and group II (electrical stimulation to supraspinatus, posterior deltoid & long head of the biceps) along with routine physiotherapy and occupational therapy for a period of 5 weeks. All patients were assessed for shoulder subluxation, pain and shoulder active abduction range of motion at the time of recruitment to study and after 5 weeks of therapy. Both the groups showed significant improvement in parameters measured. Tukey's post hoc analysis showed the results were more significant in Group II. Electrical stimulation to biceps along with the supraspinatus and posterior deltoid can more effectively reduce shoulder subluxation.

Cyclical electrical stimulation increases strength and improves activity after stroke: a systematic review.

Does electrical stimulation increase strength after stroke and are any benefits maintained beyond the intervention period or carried over to activity? Systematic review with meta-analysis of randomised or controlled trials. Adults who have had a stroke. Cyclical electrical stimulation applied in order to increase muscle strength. Strength measures had to be representative of maximum voluntary contraction and were obtained as continuous measures of force or torque, or ordinal measures such as manual muscle tests. Activity was measured using direct measures of performance that produced continuous or ordinal data, or with scales that produced ordinal data. Sixteen trials representing 17 relevant comparisons were included in this systematic review. Effect sizes were calculated as standardised mean differences because various muscles were studied and different outcome measures were used. Overall, electrical stimulation increased strength by a standardised mean difference (SMD) of 0.47 (95% CI 0.26 to 0.68) and this effect was maintained beyond the intervention period (SMD 0.33, 95% CI 0.07 to 0.60). Electrical stimulation also improved activity (SMD 0.30, 95% CI 0.05 to 0.56) and this effect was also maintained beyond the intervention period (SMD 0.38, 95% CI 0.09 to 0.66). Cyclical electrical stimulation increases strength and improves activity after stroke. These benefits were maintained beyond the intervention period with a small-to-moderate effect size. The sustained effect on activity suggests that the benefits were incorporated into daily life. Review registration: PROSPERO (CRD42013003895).

Paraplegia due to Anterior Spinal Artery Stroke: Rehabilitative Program on Lower Extremity Weakness and Locomotor Function

Background: Spinal cord ischemia in the absence of trauma with a stroke in the territories of anterior spinal artery (ASA) attributed to paradoxical embolism through patent foramen ovale (PFO) is a rare event. Rehabilitative treatment is focused on the improvement of lower limbs muscle torque to consent a recovery of balance and gait. Methods: Case report of a 43-year-old woman with paraplegia after ASA stroke due to PFO Results: A 43-year-old woman was hospitalized for sudden and progressive increase of weakness of lower limbs few hours after evacuation effort by using the Valsalva maneuver. Neurological and physiatric examination revealed paraplegia, lower limbs dysesthesia, and hesitancy with delayed bowel emptying. Spine-MRI showed D12–L1 anterolateral cord ischemia. Transcranial doppler sonography examination disclosed a PFO with moderate right-left shunt. During hospitalization, the patient was treated with steroids and acetylsalicylic acid drugs. Then, she was transferred to the Department of Physical Medicine and Rehabilitation and submitted to intensive rehabilitation of balance and gait. First, the patient was treated to increase the lower limbs torque and trunk control using also functional electrical stimulation (FES) cycling. Then, she performed an aquatic treadmill increasing contemporaneously both the weight support on the paretic legs than gait velocity. Motor and urinary symptoms disappeared in 30 days. Conclusion: After diagnostic work-up, PFO was considered the only cause of disease, suggesting that this was a case of ASA due to probable paradoxical embolism. The patient was treated with pharmacological therapy and a rehabilitative protocol with good recovery of locomotor function and muscle strength.

Intrasphincteric autologous myoblast injections with electrical stimulation for stress urinary incontinence

ObjectiveTo assess the feasibility and safety of ultrasound-guided autologous myoblast injections into the external urethral sphincter followed by electrical stimulation (ES) as a possible 2-step treatment for stress urinary incontinence (SUI). MethodsAutologous myoblasts isolated from a biceps muscle sample were injected under transurethral ultrasound guidance into the external urethral sphincter of 38 female patients. The patients also underwent ES postoperatively to enhance cell integration. Treatment feasibility, as well as possible intraoperative and postoperative complications, was assessed 6weeks after the injections. Additionally, the effects of the myoblast injections followed by an ES cycle were compared to those of a preoperative ES cycle undergone by the same patients. ResultsNo serious adverse events or complications were noted and the procedure was well tolerated. Compared with the objective and subjective measurements collected after the preoperative ES cycle, the corresponding measurements obtained 6weeks postoperatively, after the completion of a second ES cycle, indicated considerable improvement. The results to the stress test were negative for 29 (78.4%) of the patients, 5 (13.5%) considered their SUI cured, and 29 (78.4%) reported improvement. ConclusionIntrasphincteric autologous myoblast injections followed by ES is minimally invasive and feasible, and safely produced promising initial results.EU Clinical Trials EudraCT No. 2009-012389-30ClinicalTrials.gov identifier: NCT01355133

An Electric Stimulation Cycling Protocol for Gait in Incomplete Spinal Cord Injury

Page SJ, Levine P, Strayer J. An electric stimulation cycling protocol for gait in incomplete spinal cord injury. Objective To determine the feasibility and impact of an outpatient, electric stimulation cycling (ESC) protocol on a patient with incomplete spinal cord injury (SCI). Design Pre-post case study. Setting Outpatient rehabilitation hospital. Participant A 24-year old man with an incomplete SCI occurring 25 months before study entry at the T12-L1 level. Intervention A 2-phase, 10-week ESC intervention occurring 3 days a week. Phase 1 provided 30-minute ESC sessions at increasing resistance with electric stimulation applied to the quadriceps and hamstrings; phase 2 required cycling independently (ie, without stimulation) at maximal effort for increasing lengths of time. Main Outcome Measures Gait velocity, stride length, and step length, all collected during a 10-meter walking test, and the Walking Index of Spinal Cord Injury−II (WISCI-II). Results During phase 1, the patient quickly increased workload, session duration, and distance; during phase 2, duration that the subject was able to cycle without stimulation increased markedly. After the entire intervention, the subject exhibited diminished edema, new ability to voluntarily step, new ability to voluntarily dorsiflex the ankle and voluntarily flex the toe, and new ability to perform valued activities, such as transfers. He also exhibited increased mean gait velocity (.33m/s), left (.11m) and right (.07m) stride length, left (.06m) and right (.05m) step length, and a 10-point WISCI-II increase. The subject was also able to discontinue use of several medications after intervention. Conclusions SCI patients’ endurance and gait deficits can possibly be effectively addressed on an outpatient basis and with minimal assistance by using this regimen.

Muscle oxygenation during prolonged electrical stimulation-evoked cycling in paraplegics

This study investigated cardiorespiratory responses and muscle oxygenation during prolonged electrical stimulation (ES)-evoked leg cycling in individuals with paraplegia (PARA). Four PARA and 6 able-bodied (AB) persons participated in this study. Subjects performed 10 min of passive cycling and 40 min of active cycling (PARA, ES cycling; AB, voluntary cycling) at workloads selected to elicit an equivalent oxygen uptake between groups. Cycling power output, cardiorespiratory responses, mechanical efficiency, and quadriceps muscle oxygenation (measured with near-infrared spectroscopy) were measured over the duration of the exercise. Oxygen uptake was similar in both groups during active cycling (PARA, 737+/-177 mL.min(-1); AB, 840+/-90 mL.min(-1)). The cycling power output for PARA individuals commenced at 8.8 W, but varied considerably over 40 min. PARA individuals demonstrated markedly lower gross mechanical efficiency (approximately 1.3%) during ES cycling compared with AB individuals performing voluntary exercise (approximately 12.6%). During ES cycling, muscle oxygen saturation (SO2) decreased to approximately 72+/-19%, whereas SO2 during volitional cycling was unaltered from resting levels. Muscle oxygenated haemoglobin initially decreased (-23%) during ES cycling, but returned to resting levels after 10 min. Deoxygenated haemoglobin initially rose during the first 5 min of ES cycling, and remained elevated by 28% thereafter. Upon cessation of ES cycling, lower-limb muscle oxygenation increased (+93%), suggesting reactive hyperaemia in PARA individuals after such exercise. During ES cycling, muscle oxygenation followed a different pattern to that observed in AB individuals performing voluntary cycling at an equivalent VO2. Equilibrium between oxygen demand and oxygen delivery was reached during prolonged ES cycling, despite the lack of neural adjustments of leg vasculature in the paralyzed lower limbs.

Bone fracture during electrical stimulation of the quadriceps in a spinal cord injured subject

We report a fracture through the lateral femoral condyle of a paraplegic subject caused by electrical stimulation (ES). The subject was a 50-year-old man who 4 years earlier had sustained a complete spinal cord injury (SCI) at level T6. The fracture occurred during ES-induced measurement of maximal isometric torque of the quadriceps with the knee flexed at an angle of 90°. ES was delivered through surface electrodes with biphasic square wave pulses from a constant current stimulator. The torque was calculated to be 93Nm, corresponding to 20.8kg at the ankle. The regional bone mineral density of the entire lower extremities was .83g/cm 2, corresponding to 60% of sex- and age-matched able-bodied reference values. Several factors are suspected to have contributed to the fracture: maximal ES in combination with a muscle spasm, servere osteoporosis, increased muscular strength induced by regular ES cycling (twice a week), and testing position with the knee locked in 90° flexion. The risk of fracture as well as various precautions are discussed and should be taken into consideration in future studies.

Acute and chronic implantation of coiled wire intraneural electrodes during cyclical electrical stimulation

The posterior tibial nerves of 18 rabbits were intraneurally implanted with coiled wire electrodes for up to 9 weeks to evaluate their usefulness for neuromuscular electrical stimulation. In one group an electrode was implanted and removed in one leg while the other leg was chronically implanted. A second group was chronically implanted without electrical stimulation in one leg and implanted with cyclical electrical stimulation applied through the electrode in the other leg. No significant changes in nerve conduction velocities between the time of implantation and up to 9 weeks post-implantation were observed in either the stimulated or the non-stimulated nerves. Little change in motor current threshold was observed beyond 10 days post-implantation. The nerves showed little or no histologic demyelination or denervation in most specimens, although in about 40% of the nerves, a bulbous formation of connective tissue was observed at electrode entry and exit sites with some demyelination in these regions. The spinal cords showed no histologic abnormalities in either group. The gastrocnemius and soleus muscles showed only occasional signs of denervation. One cat was implanted in both the posterior tibial and peroneal nerves of each leg for a 4-year period. Threshold current showed very little change during the implantation period. The nerves showed minimal focal demyelination at the electrode site and the muscles showed normal fibers.

Effect of electrical stimulation on spasticity in hemiparetic patients.

Cyclical electrical stimulation has been applied to 10 hemiparetic patients with clinical signs of knee joint spasticity. The programme included 30 minutes of stimulation to the hamstrings followed by another 30 minutes of stimulation to the hamstrings and quadriceps. None of the patients experienced increased spasticity. The reduction in spasticity ranged from none to substantial with some other beneficial side-effects. No conclusions could be drawn as to whether hamstring stimulation is preferred to combined stimulation or to quadriceps stimulation alone. It is suggested that small portable stimulators be introduced for chronic use in spastic patients after an optimum stimulation regimen is individually established for each patient.

Electrical stimulation of wrist and fingers for hemiplegic patients.

Passive cyclical electrical stimulation was applied during a four-week treatment program to the wrist and finger extensors of 16 hemiplegic patients with flexor spasticity. The study noted the effects of this treatment on the patients' sensation; spasticity; passive range of motion of the wrist, metacarpophalangeal, and proximal interphalangeal joints; and strength in the wrist extensor muscles. Patients were divided into chronic and subacute groups. Both groups received electrical stimulation for three half-hour periods a day, seven days a week, as a substitute for all other range-of-motion techniques. Flexion contractures were prevented in the subacute group of patients at the wrist, metacarpophalangeal, and proximal interphalangeal joints. A statistically and clinically significant increase in wrist extension range occurred in the chronic group that had wrist flexion contractures before the electrical stimulation. Increased extension was noted at the metacarpophalangeal and proximal interphalangeal joints of patients in the chronic group. Those patients with some voluntary wrist extension before the treatment began were able to increase their extension strength during stimulation. No changes in skin sensation were noted and only a general trend in decreasing spasticity was apparent.