John Chae

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), obstaclxze (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.

Admission motor impairment as a predictor of physical disability after stroke rehabilitation.

The purpose of this study is to investigate the Fugl-Meyer Motor Impairment Scale and physical disability as measured by the Functional Independence Measure (FIM) as predictors of physical independence after stroke inpatient rehabilitation. Forty-eight patients admitted to a rehabilitation hospital within 6 wk of their first unifocal stroke were prospectively studied. Upper and lower extremity Fugl-Meyer scores were obtained near rehabilitation admission. FIMs were obtained on admission and discharge. Discharge FIM self-care was predicted best by admission FIM total (rs=0.75; P < 0.0001), although admission FIM self-care, other FIM components, and upper- and lower-extremity Fugl-Meyer scores were also good predictors. Discharge FIM mobility and locomotion correlated well with their admission counterparts (rs=0.54 and 0.45; P<.001 and <.01, respectively) but were even more strongly related to admission Fugl-Meyer scores (rs=0.63 and 0.74, respectively; P<0.0001). As expected, cognitive and psychosocial components of the FIM at discharge correlated poorly with admission Fugl-Meyer. These data confirm the strong motor impairment basis for the physical disability subdimensions of the FIM and suggest that dependency in physical activities of daily living after stroke is primarily determined by degree of motor impairment.

Comparison of discomfort associated with surface and percutaneous intramuscular electrical stimulation for persons with chronic hemiplegia.

Neuromuscular stimulation may facilitate motor recovery after stroke or brain injury, reduce shoulder pain associated with hemiplegia, and reduce cerebral spasticity. However, the discomfort of surface neuromuscular stimulation significantly limits the clinical implementation of this modality for persons with hemiplegia. The study contained herein tests the hypothesis that stroke and brain injury survivors with chronic hemiplegia (>6 mo) and intact sensation tolerate percutaneous intramuscular stimulation better than surface stimulation. Four stroke and two traumatic brain injury survivors participated in the study contained within this article. Each subject received three pairs of percutaneous and surface stimulations of the paretic finger extensors. The order of the type of stimulation within each pair was randomly assigned. The stimulation parameters for each type of stimulation were normalized to produce the same torque at the metacarpophalangeal joint. Subjects rated their perceived level of discomfort using a 10-cm visual analog scale and the McGill Pain Questionnaire. A blinded evaluator administered the pain measures. Percutaneous stimulation was associated with significantly lower discomfort as reflected by the visual analog scale (0.74 v 3.3; 95% confidence interval of difference, -3.84, -1.28). The McGill Pain Questionnaire produced similar results with percutaneous stimulation associated with a significantly fewer number of words chosen to describe the discomfort (0.87 v 3.30; 95% confidence interval of difference, -3.50, -1.30) and significantly lower Pain Rating Index (1.47 v 6.27; 95% confidence interval of difference, -7.77, -1.83). Data suggest that percutaneous intramuscular stimulation is significantly better tolerated than surface stimulation and that percutaneous stimulation may enhance patient compliance with neuromuscular stimulation treatments.

Functional outcome of hemorrhagic and nonhemorrhagic stroke patients after in-patient rehabilitation.

Differences in functional prognosis for patients with hemorrhagic and nonhemorrhagic strokes are unclear. The purpose of this study is to compare the functional outcome of hemorrhagic and nonhemorrhagic stroke patients after inpatient stroke rehabilitation. By retrospective review, 25 hemorrhagic stroke patients were matched with 25 nonhemorrhagic stroke patients on the basis of age and onset to admission interval. Discharge Functional Independence Measure (FIM), FIM gain, FIM efficiency, length of stay (LOS), and discharge disposition were compared. Admission FIM, gender, and comorbidities were similar between the two groups. There were no differences in discharge FIM, FIM gain, and discharge to home rates between groups. However, the hemorrhagic group had a significantly shorter LOS (31.7 v 37.6 days; P = 0.05) with higher FIM-total efficiency (0.84 v 0.60; P = 0.02). The FIM-motor scale accounted for most of the gains in efficiency (0.71 v 0.53; P = 0.05) with no significant difference in FIM-cognition efficiency between groups. Post hoc analysis revealed that onset to admission interval was a strong predictor of LOS (r = 0.62; P < 0.0001). Hemorrhagic stroke patients appear to exhibit functional gains somewhat faster than nonhemorrhagic counterparts. Confirmation of these preliminary findings must await future studies.

Intramuscular hand neuroprosthesis for chronic stroke survivors.

The purpose of this study was to assess the feasibility of a percutaneous band neuroprosthesis system for stroke survivors. Case reports of 4 chronic stroke survivors who were implanted with percutaneous intramuscular electrodes in various muscles of the forearm for hand grasp and release are presented. A percutaneous hand neuroprosthesis was able to open a spastic hemiparetic hand as long as the upper limb was in a resting position, the wrist and proximal forearm were supported, participants did not try to assist the stimulation, and an individual other than the participant modulated the stimulation. However, when participants tried to assist the stimulation or complete a functional task, hand opening was significantly reduced due to increased finger flexor hypertonia, even with increased stimulation intensity. Similarly, electrically stimulated hand opening was significantly reduced following voluntary hand closure. Techniques that provide real-time modulation of hypertonia with closed loop control, control strategies that are independent of the contralateral limb, and methods to enhance proximal control must be developed to demonstrate the feasibility of a hand neuroprosthesis system for persons with hemiparesis.

Upper limb motor function in hemiparesis: concurrent validity of the Arm Motor Ability test.

Chae J, Labatia I, Yang G: Upper limb motor function in hemiparesis: Concurrent validity of the arm motor ability test. Am J Phys Med Rehabil 2003;82:1–8. Objective To evaluate the concurrent validity of the Arm Motor Ability Test (AMAT) using the Fugl-Meyer Assessment (FMA) as the criterion measure of poststroke upper limb motor impairment. Design Upper limb motor impairment and arm ability of 30 chronic stroke survivors were assessed with the FMA and AMAT, respectively. Spearman’s correlation coefficients were generated relating the components of FMA and AMAT. Scatterplots were generated to provide qualitative assessments of the relationship between FMA and AMAT. Bar graphs of FMA and AMAT normalized to their maximum scores were generated to compare the levels of motor status measured by each instrument. Results All components of AMAT correlated highly with FMA total (r = 0.92–0.94;P < 0.001). AMAT functional ability and AMAT quality of movement were linearly related with FMA total. However, AMAT time of performance exhibited significant ceiling and floor effects with respect to FMA. Normalized AMAT scores were generally lower than normalized FMA scores (P < 0.001), with the greatest difference in scores observed in subjects with more severe motor impairments. Conclusion This study demonstrates a high degree of concurrent criterion validity of the AMAT. However, AMAT tends to underestimate the arm motor status of those with more severe motor impairments.

Intramuscular electromyographically controlled neuromuscular electrical stimulation for upper limb recovery in chronic hemiplegia.

We report three cases of survivors of chronic stroke who were treated with active repetitive movement training of the paretic finger extensors mediated by intramuscular electromyographically controlled neuromuscular electrical stimulation for the purpose of motor relearning. These case reports demonstrate the feasibility of using intramuscular electromyographically controlled neuromuscular electrical stimulation for facilitating the upper limb motor recovery of chronic stroke survivors with mild to moderate hemiplegia.

A novel functional electrical stimulation treatment for recovery of hand function in hemiplegia: 12-week pilot study.

Background. Loss of finger extension is common after stroke and can severely limit hand function. Contralaterally controlled functional electrical stimulation (CCFES) is a new treatment aimed at restoring volitional finger and thumb extension. A previous pilot study showed reductions in hand impairment after 6 weeks of CCFES, but the effect did not persist after end of treatment. Objective. This study aimed to evaluate the feasibility of achieving greater and more persistent gains with CCFES by increasing the treatment period to 12 weeks. Methods. CCFES uses neuromuscular electrical stimulation to open the paretic hand in direct proportion to the degree of volitional opening of the unimpaired contralateral hand, which is detected by an instrumented glove. Three subjects with chronic hemiplegia participated in a 12-week CCFES treatment, which consisted of daily CCFES-assisted active repetitive hand-opening exercises and twice weekly functional task practice with CCFES. Results. Maximum voluntary finger extension increased by 101° and 68° for subjects 1 and 2, respectively, but subject 3 had no improvement in finger extension. Box and Block score increased by 6, 15, and 7 blocks, and upper extremity Fugl-Meyer score increased by 11, 15, and 7 points for subjects 1, 2, and 3, respectively. The finger extension gains declined at the 1-month and 3-month follow-up for subjects 1 and 2, but the gains in Box and Block and Fugl-Meyer scores persisted at follow-up. Conclusions. Greater reductions in hand impairment were achieved by extending the treatment period. The effect and its longevity may be related to baseline impairment level.

Contralaterally Controlled Functional Electrical Stimulation for Upper Extremity Hemiplegia An Early-Phase Randomized Clinical Trial in Subacute Stroke Patients

Background. Contralaterally controlled functional electrical stimulation (CCFES) is an experimental treatment intended to improve hand function after stroke. Objective. To compare the effects of 6 weeks of CCFES versus cyclic neuromuscular electrical stimulation (NMES) on upper extremity impairment and activity limitation in patients ≤6 months poststroke. Methods. Twenty-one participants were randomized to CCFES or cyclic NMES. Treatment for both groups consisted of daily stimulation-assisted repetitive hand-opening exercise at home plus twice-weekly lab sessions of functional task practice. Assessments were made at pretreatment and posttreatment and at 1 month and 3 months posttreatment. They included maximum voluntary finger extension angle, finger movement tracking error, upper extremity Fugl-Meyer score, Box and Blocks test, and Arm Motor Abilities test. Treatment effects were estimated using a 2-factor repeated measures analysis of variance with the value of the baseline measure as a covariate. Results. Seventeen patients completed the treatment phase (9 CCFES, 8 cyclic NMES). At all posttreatment time points, CCFES produced larger improvements than cyclic NMES on every outcome measure. Maximum voluntary finger extension showed the largest treatment effect, with a mean group difference across the posttreatment time points of 28° more finger extension for CCFES. Conclusions. The results favor CCFES over cyclic NMES though the small sample size limits the statistical power of the study. The effect size estimates from this study will be used to power a larger trial.

Peripheral nerve stimulation compared with usual care for pain relief of hemiplegic shoulder pain: a randomized controlled trial.

ObjectiveThis study sought to establish the efficacy of single-lead, 3-wk peripheral nerve stimulation (PNS) therapy for pain reduction in stroke survivors with chronic hemiplegic shoulder pain. DesignThis study is a single-site, pilot, randomized controlled trial of adults with chronic shoulder pain after stroke. Participants were randomized to receive a 3-wk treatment of single-lead PNS or usual care. The primary outcome was the worst pain in the last week (Brief Pain Inventory, Short Form, question 3) measured at baseline and weeks 1, 4, 12, and 16. The secondary outcomes included pain interference (Brief Pain Inventory, Short Form, question 9), pain measured by the ShoulderQ Visual Graphic Rating Scales, and health-related quality-of-life (Short-Form 36 version 2). ResultsTwenty-five participants were recruited, 13 to PNS and 12 to usual care. There was a significantly greater reduction in pain for the PNS group compared with the controls, with significant differences at 6 and 12 wks after treatment. Both PNS and usual care were associated with significant improvements in pain interference and physical health-related quality-of-life. ConclusionsShort-term PNS is a safe and efficacious treatment of shoulder pain. Pain reduction is greater compared with usual care and is maintained for at least 12 wks after treatment.