Upper-Limb Recovery After Stroke: A Randomized Controlled Trial Comparing EMG-Triggered, Cyclic, and Sensory Electrical Stimulation.

BACKGROUND AND PURPOSE: This study compared the effect of cyclic neuromuscular electrical stimulation (NMES), electromyographically (EMG)-triggered NMES, and sensory stimulation on motor impairment and activity limitations in patients with upper-limb hemiplegia. METHODS: This was a multicenter, single-blind, multiarm parallel-group study of nonhospitalized hemiplegic stroke survivors within 6 months of stroke. A total of 122 individuals were randomized to receive either cyclic NMES, EMG-triggered NMES, or sensory stimulation twice every weekday in 40-minute sessions, over an 8 week-period. Patients were followed for 6 months after treatment concluded. RESULTS: There were significant increases in the Fugl-Meyer Assessment [F(1, 111) = 92.6, P < .001], FMA Wrist and Hand [F(1, 111) = 66.7, P < .001], and modified Arm Motor Ability Test [mAMAT; time effect: F(1, 111) = 91.0, P < .001] for all 3 groups. There was no significant difference in the improvement among groups in the FMA [F(2, 384) = 0.2, P = .83], FMA Wrist and Hand [F(2, 384) = 0.4, P = .70], or the mAMAT [F(2, 379) = 1.2, P = .31]. CONCLUSIONS: All groups exhibited significant improvement of impairment and functional limitation with electrical stimulation therapy applied within 6 months of stroke. Improvements were likely a result of spontaneous recovery. There was no difference based on the type of electrical stimulation that was administered.

Hemiparetic Gait.

The most common pattern of walking impairment poststroke is hemiparetic gait, which is characterized by asymmetry associated with an extensor synergy pattern of hip extension and adduction, knee extension, and ankle plantar flexion and inversion. There are characteristic changes in the spatiotemporal, kinematic and kinetic parameters, and dynamic electromyography patterns in hemiparesis, which may be assessed most accurately in a motion studies laboratory. An understanding of normal human gait is necessary to assess the complex interplay of motor, sensory, and proprioceptive loss; spasticity; and/or ataxia on hemiparetic gait.

Neuromuscular Electrical Stimulation for Motor Restoration in Hemiplegia.

This article reviews the most common therapeutic and neuroprosthetic applications of neuromuscular electrical stimulation (NMES) for upper and lower extremity stroke rehabilitation. Fundamental NMES principles and purposes in stroke rehabilitation are explained. NMES modalities used for upper and lower limb rehabilitation are described, and efficacy studies are summarized. The evidence for peripheral and central mechanisms of action is also summarized.

Surface peroneal nerve stimulation in lower limb hemiparesis: effect on quantitative gait parameters.

OBJECTIVE: The objective of this study was to evaluate possible mechanisms for functional improvement and compare ambulation training with surface peroneal nerve stimulation vs. usual care via quantitative gait analysis. DESIGN: This study is a randomized controlled clinical trial. SETTING: The setting of this study is a teaching hospital of an academic medical center. PARTICIPANTS: One hundred ten chronic stroke survivors (>12 wks poststroke) with unilateral hemiparesis participated in this study. INTERVENTIONS: The subjects were randomized to a surface peroneal nerve stimulation device or usual care intervention. The subjects were treated for 12 wks and followed up for 6-mo posttreatment. MAIN OUTCOME MEASURES: Spatiotemporal, kinematic, and kinetic parameters of gait were the main outcome measures. RESULTS: Cadence (F3,153 = 5.81, P = 0.012), stride length (F3,179 = 20.01, P < 0.001), walking speed (F3,167 = 18.2, P < 0.001), anterior-posterior ground reaction force (F3,164 = 6.61, P = 0.004), peak hip power in preswing (F3,156 = 8.76, P < 0.001), and peak ankle power at push-off (F3,149 = 6.38, P = 0.005) all improved with respect to time. However, peak ankle ankle dorsiflexion in swing (F3,184 = 4.99, P = 0.031) worsened. In general, the greatest change for all parameters occurred during the treatment period. There were no significant treatment group × time interaction effects for any of the spatiotemporal, kinematic, or kinetic parameters. CONCLUSIONS: Gait training with peroneal nerve stimulation and usual care was associated with improvements in peak hip power in preswing and peak ankle power at push-off, which may have resulted in improved cadence, stride length, and walking speed; however, there were no differences between treatment groups. Both treatment groups also experienced a decrease in peak ankle ankle dorsiflexion in swing, although the clinical implications of this finding are unclear.

Effect of body mass index on hemiparetic gait.

OBJECTIVE: To evaluate the relationship between body mass index (BMI) and spatiotemporal, kinematic, and kinetic gait parameters in chronic hemiparetic stroke survivors. DESIGN: Secondary analysis of data collected in a randomized controlled trial comparing two 12-week ambulation training treatments. SETTING: Academic medical center. PARTICIPANTS: Chronic hemiparetic stroke survivors (N = 108, >3 months poststroke) METHODS: Linear regression analyses were performed of BMI, and selected pretreatment gait parameters were recorded using quantitative gait analysis. MAIN OUTCOME MEASURES: Spatiotemporal, kinematic, and kinetic gait parameters. RESULTS: A series of linear regression models that controlled for age, gender, stroke type (ischemic versus hemorrhagic), interval poststroke, level of motor impairment (Fugl-Meyer score), and walking speed found BMI to be positively associated with step width (m) (ß = 0.364, P < .001), positively associated with peak hip abduction angle of the nonparetic limb during stance (deg) (ß = 0.177, P = .040), negatively associated with ankle dorsiflexion angle at initial contact of the paretic limb (deg) (ß = -0.222, P = .023), and negatively associated with peak ankle power at push-off (W/kg) of the paretic limb (W/kg)(ß = -0.142, P = .026). CONCLUSIONS: When walking at a similar speed, chronic hemiparetic stroke subjects with a higher BMI demonstrated greater step width, greater hip hiking of the paretic lower limb, less paretic limb dorsiflexion at initial contact, and less paretic ankle power at push-off as compared to stroke subjects with a lower BMI and similar level of motor impairment. Further studies are necessary to determine the clinical relevance of these findings with respect to rehabilitation strategies for gait dysfunction in hemiparetic patients with higher BMIs.

Minimal depression: how does it relate to upper-extremity impairment and function in stroke?

OBJECTIVE. We sought to determine the association between minimal depression, upper-extremity (UE) impairment, and UE motor function in a cohort of participants with subacute stroke. METHOD. We conducted a retrospective, secondary analysis of an interventional study. Correlational analyses were performed using the following outcome measures: the UE section of the Fugl-Meyer Assessment (FM), the functional ability section of the Arm Motor Ability Test (AMAT), and the Beck Depression Inventory (BDI-II). RESULTS. We found a negative correlation between BDI-II and both the FM (-.120, p = .196) and the AMAT (-.110, p = .275); however, this correlation was not statistically significant. Women exhibited higher depression scores (8.75 ± 0.78) than men (6.29 ± 0.46; p = .008). CONCLUSION. Low levels of depression are not associated with UE motor impairment and function in people with minimal to moderate UE disability levels. Poststroke depression occurs more frequently in women, warranting additional research on sex-specific differences. Given the proliferation of UE therapies targeting this group, this information is important for effective therapy planning and implementation.

Contralaterally controlled neuromuscular electrical stimulation for recovery of ankle dorsiflexion: a pilot randomized controlled trial in patients with chronic post-stroke hemiplegia.

OBJECTIVE: The aim of this study was to compare the effects of contralaterally controlled neuromuscular electrical stimulation (CCNMES) vs. cyclic neuromuscular electrical stimulation (NMES) on lower extremity impairment, functional ambulation, and gait characteristics. DESIGN: Twenty-six survivors of stroke with chronic (≥6 mos) foot drop during ambulation were randomly assigned to 6 wks of CCNMES or cyclic NMES. Both groups had ten sessions per week of self-administered home application of either CCNMES or cyclic NMES plus two sessions per week of gait training with a physical therapist. Primary outcomes included lower extremity Fugl-Meyer score, modified Emory Functional Ambulation Profile, and gait velocity. Assessments were made at pretreatment and posttreatment and at 1 and 3 mos after treatment. RESULTS: There were no significant differences between the groups in the outcome trajectories for any of the measures. With data from both groups pooled, there were significant but modest and sustained improvements in the Fugl-Meyer score and the modified Emory Functional Ambulation Profile but not in gait velocity. CONCLUSIONS: The results support the hypothesis that gait training combined with either CCNMES or cyclic NMES reduces lower extremity impairment and functional ambulation but do not support the hypothesis that CCNMES is more effective than cyclic NMES in patients with chronic post-stroke hemiplegia.

Technological advances in interventions to enhance poststroke gait.

Neurologic rehabilitation interventions may be either therapeutic or compensatory. Included in this article are lower extremity functional electrical stimulation, body weight-supported treadmill training, and lower extremity robotic-assisted gait training. These poststroke gait training therapies are predicated on activity-dependent neuroplasticity. All three interventions have been trialed extensively in research and clinical settings to show a positive effect on various gait parameters and measures of walking performance. This article provides an overview of evidence-based research that supports the efficacy of these three interventions to improve gait, as well as providing perspective on future developments to enhance poststroke gait in neurologic rehabilitation.

Randomized controlled trial of surface peroneal nerve stimulation for motor relearning in lower limb hemiparesis.

OBJECTIVE: To compare the motor relearning effect of a surface peroneal nerve stimulator (PNS) versus usual care on lower limb motor impairment, activity limitation, and quality of life among chronic stroke survivors. DESIGN: Single-blinded randomized controlled trial. SETTING: Teaching hospital of academic medical center. PARTICIPANTS: Chronic stroke survivors (N=110; >12wk poststroke) with unilateral hemiparesis and dorsiflexion strength of ≤4/5 on the Medical Research Council scale. INTERVENTIONS: Subjects were stratified by motor impairment level and then randomly assigned to ambulation training with either a surface PNS device or usual care (ankle-foot orthosis or no device) intervention. Subjects were treated for 12 weeks and followed up for 6 months posttreatment. MAIN OUTCOME MEASURES: Lower limb portion of the Fugl-Meyer (FM) Assessment (motor impairment), the modified Emory Functional Ambulation Profile (mEFAP) performed without a device (functional ambulation), and the Stroke Specific Quality of Life (SSQOL) scale. RESULTS: There was no significant treatment group main effect or treatment group by time interaction effect on FM, mEFAP, or SSQOL raw scores (P>.05). The time effect was significant for the 3 raw scores (P<.05). However, when comparing average change scores from baseline (t1) to end of treatment (t2, 12wk), and at 12 weeks (t3) and 24 weeks (t4) after end of treatment, significant differences were noted only for the mEFAP and SSQOL scores. The change in the average scores for both mEFAP and SSQOL occurred between t1 and t2, followed by relative stability thereafter. CONCLUSIONS: There was no evidence of a motor relearning effect on lower limb motor impairment in either the PNS or usual-care groups. However, both the PNS and usual-care groups demonstrated significant improvements in functional mobility and quality of life during the treatment period, which were maintained at 6-month follow-up.

Spatiotemporal, kinematic, and kinetic effects of a peroneal nerve stimulator versus an ankle foot orthosis in hemiparetic gait.

BACKGROUND: The relative effect of a transcutaneous peroneal nerve stimulator (tPNS) and an ankle foot orthosis (AFO) on spatiotemporal, kinematic, and kinetic parameters of hemiparetic gait has not been well described. OBJECTIVE: To compare the relative neuroprosthetic effect of a tPNS with the orthotic effect of an AFO using quantitative gait analysis (QGA). DESIGN: In all, 12 stroke survivors underwent QGA under 3 device conditions: (1) no device (ND), (2) AFO, and (3) tPNS. A series of repeated-measures analyses of variance (rmANOVAs) were performed with dorsiflexion status (presence or absence of volitional dorsiflexion) as a covariate to compare selected spatiotemporal, kinematic, and kinetic parameters for each device condition. Post hoc pairwise comparisons and/or subset analysis by dorsiflexion status were performed for significant effect. RESULTS: Stride length was improved with both the AFO (P = .035) and the tPNS (P = .029) relative to ND. Those with absent dorsiflexion had longer stride length with the tPNS relative to ND (P = .034) and a higher walking velocity with a tPNS relative to the AFO (P = .015). There was no device effect on dorsiflexion angle at initial contact; however, a significant Device × Dorsiflexion status interaction effect favored the AFO relative to ND (P = .025) in those with dorsiflexion present. CONCLUSION: This study suggests that level of motor impairment may influence the relative effects of the tPNS and AFO devices in chronic hemiparetic gait; however, the small sample size limits generalizability. Future studies are necessary to determine if motor impairment level should be considered in the clinical prescription of these devices.

Relationship between body mass index and rehabilitation outcomes in chronic stroke.

OBJECTIVE: The aim of this study was to evaluate the relationship between body mass index (BMI) and change in motor impairment and functional mobility after a gait rehabilitation intervention in chronic stroke subjects. DESIGN: Correlation and linear regression analyses of pretreatment and end-of-treatment Fugl-Meyer scores and modified Emory Functional Ambulation Profile scores from hemiparetic subjects (n = 108, >3 mos post stroke) who participated in a randomized controlled trial comparing two 12-wk ambulation training treatments were generated. RESULTS: A series of linear regression models that controlled for age, sex, stroke type, interval post-stroke, and training device found the change in the Fugl-Meyer score to be significantly negatively associated with pretreatment BMI (ß = -0.207, P = 0.036) and the change in the "up and go" modified Emory Functional Ambulation Profile score to be significantly positively associated with BMI (ß = 0.216, P = 0.03). Changes in modified Emory Functional Ambulation Profile scores in floor, carpet, obstacles, or stair climbing were not significantly associated with BMI. CONCLUSIONS: Chronic stroke subjects with a higher BMI were less likely to demonstrate improvement in motor impairment and up and go functional mobility performance in response to ambulation training, irrespective of treatment intervention. Stroke rehabilitation clinicians should consider BMI when formulating rehabilitation goals. Further studies are necessary to determine whether obesity is a predictor of longer-term post-stroke motor and functional recovery.

Spatiotemporal and kinematic effect of peroneal nerve stimulation versus an ankle-foot orthosis in patients with multiple sclerosis: a case series.

OBJECTIVE: To compare the effect of a surface peroneal nerve stimulator (PNS) versus an ankle-foot orthosis (AFO) on spatiotemporal and kinematic parameters of gait in patients with multiple sclerosis. DESIGN: This was a case series design. PARTICIPANTS: Four subjects with multiple sclerosis and dorsiflexion weakness. INTERVENTION: Quantitative gait analysis with the use of (1) no device, (2) AFO, and (3) PNS as a single point-in-time assessment. OUTCOME MEASURES: Included walking speed, stride length, cadence, and double support time; kinematic parameters included peak pelvic obliquity during swing, peak contralateral hip abduction during stance, peak knee flexion and hip flexion during swing, ankle dorsiflexion at initial contact, and peak ankle internal rotation during swing. RESULTS: One-way analysis of variance was used to compare intrasubject performance under the 3 device conditions. The PNS significantly increased ankle dorsiflexion angle at initial contact, as compared with both no device and the AFO, in 3 of the 4 subjects. However, other spatiotemporal and kinematic gait parameters were more variably affected by the device conditions. CONCLUSIONS: With the exception of ankle dorsiflexion angle at initial contact, PNS and AFO have a variable effect on spatiotemporal and kinematic gait parameters in individual subjects with multiple sclerosis. Further studies are indicated to determine the clinical significance of intrasubject differences between device conditions.

Neuroprosthetic effect of peroneal nerve stimulation in multiple sclerosis: a preliminary study.

OBJECTIVE: To determine the neuroprosthetic effect of a peroneal nerve stimulator on tasks of functional ambulation in multiple sclerosis (MS). DESIGN: A single point-in-time assessment of functional ambulation tasks under the conditions of no device and peroneal nerve stimulator. SETTING: Outpatient academic medical center. PARTICIPANTS: Participants (N=11) with diagnosis of MS (>6mo), dorsiflexion weakness, and prior usage of an ankle-foot orthosis. INTERVENTION: Surface peroneal nerve stimulator for ambulation. MAIN OUTCOME MEASURES: Timed 25-foot Walk portion of the MS Functional Composite; Floor, Carpet, Up and Go, Obstacle, and Stair components of the Modified Emory Functional Ambulation Profile. RESULTS: Peroneal nerve stimulator-Stair performance was significantly enhanced (P=.05) versus no device, and statistical significance was approached for peroneal nerve stimulator-Obstacles (P=.09) versus no device. There were no significant differences between peroneal nerve stimulator and no device conditions in the remaining outcome measures. CONCLUSIONS: The neuroprosthetic effect of the peroneal nerve stimulator is modest relative to no device in the performance of specific functional tasks of ambulation in MS gait. A longitudinal, controlled trial is needed to show effectiveness.

Neuromuscular electrical stimulation for motor restoration in hemiplegia.

Clinical applications of neuromuscular electrical stimulation (NMES) in stroke rehabilitation provide both therapeutic and functional benefits. Therapeutic applications include upper and lower limb motor relearning and reduction of poststroke shoulder pain. There is growing evidence that NMES, especially those approaches that incorporate task-specific strategies, is effective in facilitating upper and lower limb motor relearning. There is also strong evidence that NMES reduces poststroke shoulder subluxation and pain. Functional applications include upper and lower limb neuroprostheses. Lower limb neuroprostheses in the form of peroneal nerve stimulators is effective in enhancing the gait speed of stroke survivors with foot-drop. The development of hand neuroprostheses is in its infancy and must await additional fundamental and technical advances before reaching clinical viability. The limitations of available systems and future developments are discussed.

Functional effect of an ankle foot orthosis on gait in multiple sclerosis: a pilot study.

OBJECTIVE: The objective was to determine whether an ankle foot orthosis improves gait velocity and tasks of functional ambulation in multiple sclerosis (MS). DESIGN: This cross-sectional study enrolled 15 participants with diagnosis of MS, dorsiflexion and eversion weakness, and more than 3 mos of using a physician-prescribed ankle foot orthosis (AFO). Subject ambulation was evaluated (1) without an AFO and (2) with an AFO. Outcome measures were the Timed 25-Foot (T25-FW) Walk portion of the Multiple Sclerosis Functional Composite (MSFC) and the five trials (Floor, Carpet, Up and Go, Obstacles, Stairs) of the Modified Emory Functional Ambulation Profile (mEFAP). RESULTS: The mean timed differences on the T25-FW and the five components of the mEFAP between the AFO vs. no device trials were not statistically significant. CONCLUSIONS: In MS subjects with dorsiflexion and eversion weakness, no statistically significant improvement was found performing timed tasks of functional ambulation with an AFO.

Improvement in functional ambulation as a therapeutic effect of peroneal nerve stimulation in hemiplegia: two case reports.

Two chronic stroke survivors who utilized an ankle foot orthosis (AFO) prior to study entry were evaluated at baseline and after 4 weeks of daily use of a surface peroneal nerve stimulator. Participants were assessed without their dorsiflexor assistive device, using the modified Emory Functional Ambulation Profile (mEFAP). The participants demonstrated improvement in all 5 components of the mEFAP relative to baseline. These case reports indicate that enhanced functional ambulation may be an important therapeutic effect of peroneal nerve stimulation. Potential mechanisms are discussed. Controlled trials are needed to demonstrate a cause-and-effect relationship.

Neuromuscular electrical stimulation in neurorehabilitation.

This review provides a comprehensive overview of the clinical uses of neuromuscular electrical stimulation (NMES) for functional and therapeutic applications in subjects with spinal cord injury or stroke. Functional applications refer to the use of NMES to activate paralyzed muscles in precise sequence and magnitude to directly accomplish functional tasks. In therapeutic applications, NMES may lead to a specific effect that enhances function, but does not directly provide function. The specific neuroprosthetic or "functional" applications reviewed in this article include upper- and lower-limb motor movement for self-care tasks and mobility, respectively, bladder function, and respiratory control. Specific therapeutic applications include motor relearning, reduction of hemiplegic shoulder pain, muscle strengthening, prevention of muscle atrophy, prophylaxis of deep venous thrombosis, improvement of tissue oxygenation and peripheral hemodynamic functioning, and cardiopulmonary conditioning. Perspectives on future developments and clinical applications of NMES are presented.

Peroneal nerve stimulation versus an ankle foot orthosis for correction of footdrop in stroke: impact on functional ambulation.

OBJECTIVE: To compare the efficacy of the Odstock Dropped-Foot Stimulator (ODFS), a transcutaneous peroneal nerve stimulation device, versus an ankle foot orthosis (AFO) in improving functional ambulation of chronic stroke survivors. INTERVENTION: Fourteen chronic stroke survivors with foot-drop participated in the study. Participants received ambulation training under 3 test conditions: 1) ODFS, 2) customized AFO, and 3) no device. Each participant was evaluated using the modified Emory Functional Ambulation Profile under the 3 test conditions. All participants were evaluated with a post-evaluation survey to solicit device feedback and preferences. RESULTS: Functional ambulation with the AFO was significantly improved, relative to no device, on the floor (P = 0.000), carpet (P = 0.013), and "up and go" test (P = 0.042). There was a trend toward significance on the obstacle (P = 0.092) and stair (P = 0.067) trials. Functional ambulation with the ODFS was significantly improved, relative to no device, on the carpet(P = 0.004). A trend toward significance on floor (P = 0.081), obstacle (P = 0.092), and stair (P = 0.079) trials was observed. The difference in functional ambulation between the AFO and ODFS showed a trend toward statistical significance on floor (P = 0.065) and up and go (P = 0.082) trials only. Given a choice between the ODFS and AFO for long-term correction of footdrop, participants indicated a preference for the ODFS. CONCLUSION: The AFO and the ODFS may be comparable in their effect on improving functional ambulation as compared to no device. Specific characteristics of the ODFS may make it a preferred intervention by stroke survivors. More rigorously controlled trials are needed to confirm these findings.