Published papers

Abstract Objective This study aimed to investigate the feasibility of a neurorehabilitation pipeline and develop an algorithm to automatically select the appropriate treatment for individuals with upper extremity motor paralysis after stroke in the chronic phase. Design In Experiment 1, eight post-stroke participants in the chronic phase who underwent treatment sustaining two to three phases were assessed before and after treatment. In Experiment 2, a decision tree analysis was performed in which the dependent variable was set as the treatment option determined by a board-certified physiatrist for 95 post-stroke participants; the independent variables were only motor function scores or both motor function scores and electromyogram variables. Results In Experiment 1, the clinical assessment scores were improved significantly after treatment. Experiment 2 showed that the agreements of the model with only motor function scores as the dependent variable and with motor function scores and electromyogram variables as the dependent variables were 75.8% and 82.1%, respectively. Conclusions This novel treatment package is feasible for improvement of motor function in post-stroke individuals with severe motor paralysis. The study also established an automated algorithm for selecting appropriate treatments for upper extremity motor paralysis after stroke, identifying standard values of key variables, including electromyography variables.

We previously reported reliability and validity of our newly developed comorbidity scale (CS) for stroke outcome research based on a retrospective sample. The objectives of this study were to cross-validate the comorbidity scale in a new prospective sample and to investigate longitudinal changes of the comorbidity scale during hospitalization. In a prospective sample of 175 stroke patients admitted to five nonacute rehabilitation hospitals in Japan, we analyzed the frequency and grading of comorbidities and compared the comorbidity scale with demographic data, impairment as assessed with the Stroke Impairment Assessment Set (SIAS), and disability as measured with the Functional Independence Measure (FIM(SM)). The results were compared with our previous retrospective study. We also studied longitudinal changes by measuring the comorbidity scale on admission, 2 wk later, and at discharge of 67 patients. As a result, the comorbidity scaling was significantly lower in the prospective sample, and it increased at the second measurement and then plateaued. Among the comorbidities, hypertension ranked first, followed by shoulder pain, and diabetes mellitus. Similar to our previous retrospective study, the comorbidity scale correlated positively with age and length of stay and correlated negatively with the SIAS motor item scores and the FIM scores. In conclusion, the present study suggested concurrent and predictive validity of the comorbidity scale in a prospective sample as well and clarified the comorbidity characteristics of stroke inpatients.

Objective: The purpose of this study was to investigate reliability, validity, internal structure, and responsiveness of our newly developed Trunk Impairment Scale (TIS) for patients with stroke. Design: A total of 73 patients with stroke participated in this prospective study. Interrater reliability (weighted kappa statistics), content validity (principal component analysis), concurrent validity (Spearman's rank correlation with the Trunk Control Test), predictive validity (prediction of discharge FIM™ scores), and responsiveness (standardized response mean values) were examined. Internal consistency and item difficulties were analyzed with Rasch analysis. Results: The weighted kappa of each TIS item ranged from 0.66 to 1.0. Principal component analysis revealed that the TIS measured a domain similar to the Stroke Impairment Assessment Set trunk items but different from the Stroke Impairment Assessment Set motor and visuospatial items. The TIS correlated with the Trunk Control Test (r = 0.91). To predict discharge FIM motor scores, addition of the TIS as one of the predictors to age, time from onset, and admission FIM score increased the adjusted R2 from 0.66 to 0.75. With Rasch analysis, the misfit was acceptable, except for the abdominal muscle strength item. The difficulty patterns were similar at admission and discharge, except for the abdominal muscle strength item. The responsiveness of the TIS was satisfactory and comparable with that of the Trunk Control Test (standardized response mean values, 0.94 and 1.06). Conclusions: Our newly developed TIS is reliable, valid, and responsive for use in stroke outcome research.

Objective: To determine whether visual evoked fields (VEFs) elicited by right and left hemifield stimulation differ in patients with unilateral spatial neglect that results from cerebrovascular accident. Methods: Pattern-reversal stimulation of the right and left hemifield was performed in three patients with left unilateral spatial neglect. Magnetoencephalography was recorded using a 160-channel system, and VEFs were quantified in the 400 ms after each stimulus. The presence or absence of VEF components at around 100 ms (P100m component) and 145 ms (N145m component) after stimulus onset was determined. The source of the VEF was determined using a single equivalent current dipole model for spherical volume conduction. All patients were evaluated using the behavioral inattention test (BIT). Results: In response to right hemifield stimulation, the P100m and N145m components of the VEF were evident in all three patients. In response to left hemifield stimulation, both components were evident in Patient 3, whereas only the P100m component was evident in Patient 1 and only the N145m component was evident in Patient 2. Patient 1 exhibited impairments on the line bisection and cancellation tasks of the BIT, Patient 2 exhibited impairments on the copying, drawing and cancellation tasks of the BIT, and Patient 3 exhibited impairments on the cancellation task of the BIT. Conclusions: These results demonstrate that early VEFs are disrupted in patients with unilateral spatial neglect and support the concept that deficits in visual processing differ according to the clinical subtype of unilateral spatial neglect and the lesion location. This study also demonstrates the feasibility of using magnetoencephalography to explore subtypes of neglect. © 2013 Mizuno, Tsuji, Rossetti, Pisella, Ohde and Liu.

It is known that weak transcranial direct current stimulation (tDCS) induces persistent excitability changes in the cerebral cortex. There are, however, few studies that compare the after-effects of anodal versus cathodal tDCS in patients with stroke. This study assessed the after-effects of tDCS over the motor cortex in patients with hemiparetic stroke and healthy volunteers. Seven stroke patients and nine healthy volunteers were recruited. Ten minutes of anodal and cathodal tDCS (1 mA) and sham stimulation were applied to the affected primary motor cortex (M1) on different days. In healthy subjects, tDCS was applied to the right M1. Before and after tDCS, motor-evoked potentials (MEPs) in the first dorsal interosseous (FDI) muscle and silent period were measured. Anodal tDCS increased the MEPs of the affected FDI in patients with stroke as well as in healthy subjects. Cathodal tDCS increased the MEPs of the affected FDI in patients with stroke. In healthy subjects, however, cathodal tDCS decreased the MEPs. We found no significant change in the duration of the silent period after anodal or cathodal tDCS. We found that both anodal and cathodal tDCS increased the affected M1 excitability in patients with stroke. It is thought that the after-effects of tDCS are different in patients with stroke compared with healthy subjects. © 2012 Informa Healthcare USA, Inc.

The sensorimotor cortex activity measured by scalp EEG shows coherence with electromyogram (EMG) activity within the 15- to 35-Hz frequency band (β-band) during weak to moderate intensity of isometric voluntary contraction. This coupling is known to change its frequency band to the 35- to 60-Hz band (γ-band) during strong contraction. This study aimed to examine whether such contraction level-related modulation of corticomuscular coupling differs between muscles with different muscle compositions and functions. In 11 healthy young adults, we quantified the coherence between EEG over the sensorimotor cortex and rectified EMG during tonic isometric voluntary contraction at 10-70% of maximal voluntary contraction of the tibialis anterior (TA) and soleus (SOL) muscles, respectively. In the TA, the EEG-EMG coherence shifted from the β-band to the γ-band with increasing contraction level. Indeed, the magnitude of β-band EEG-EMG coherence was significantly decreased, whereas that of γ-band coherence was significantly increased, when the contraction level was above 60% of maximal voluntary contraction. In contrast to the TA, the SOL showed no such frequency changes of EEG-EMG coherence with alterations in the contraction levels. In other words, the maximal peak of EEG-EMG coherence in the SOL existed within the β-band, irrespective of the contraction levels. These findings suggest that the central nervous system regulates the frequency of corticomuscular coupling to exert the desired levels of muscle force and, notably, that the applicable rhythmicity of the coupling for performing strong contractions differs between muscles, depending on the physiological muscle compositions and functions of the contracting muscle. Copyright © 2012 the American Physiological Society.

Background and objective. Hybrid assistive neuromuscular dynamic stimulation (HANDS) therapy was devised to facilitate the use of the hemiparetic upper extremity in daily life by combining assistive neuromuscular electrical stimulation, referred to as the integrated volitional electrical stimulator (IVES), with a splint. The aim of this study is to assess the effectiveness of HANDS therapy for patients with subacute stroke. Methods. The participants were 24 inpatients receiving rehabilitation for hemiparetic stroke within 60 days of onset. Entry criteria included inability to individuate finger extension. Patients were randomly assigned to 2 groups. The HANDS group (n = 12) used the IVES combined with a wrist splint for 8 hours a day for 3 weeks, and the control group (n = 12) wore a wrist splint alone. All patients received the same daily dose and length of standard poststroke multidisciplinary rehabilitation. Outcome measures were the upper extremity portion of the Fugl-Meyer Assessment (FMA), Action Research Arm Test (ARAT), and Motor Activity Log-14 (MAL). Results. In all, 10 patients in each group completed the interventions. Compared with the control group, the HANDS group showed significantly greater gains in distal (wrist/hand) portion of the FMA (P <.01) and improvement of the ARAT (P <.05). The gains in the MAL did not differ. No adverse effects occurred and the HANDS therapy was well accepted. Conclusion. HANDS therapy in addition to conventional therapy may improve hand function in patients with moderate to severe hand impairment during early rehabilitation. © 2011 American Society of Neurorehabilitation.

Purpose. To investigate swallowing problems in patients with Duchenne muscular dystrophy (DMD) using a questionnaire and videofluorography (VF). Method. A questionnaire survey was performed of swallowing-related symptoms and VF in 31 male patients with DMD (mean age 19.9 years, range 9-26 years). The relationships among age, frequency of symptoms and VF abnormalities were analysed using Spearman's rank correlation. The differences in VF abnormalities among different food textures were analysed with the Kruskal-Wallis test. Results. Symptoms related to pharyngeal phase dysfunction were more frequent than those related to oral and oesophageal phases. Coughing while eating was seen in 71% of the patients, choking while eating in 32% and the need to clear the throat in 26%. VF abnormalities were observed in 30 patients (96.8%). Common VF abnormalities included pooling in the valleculae (90.3%) and in the pyriform sinus (90.3%). Pharyngo-oral regurgitation was seen in 35.5% of the patients. Pooling in the pyriform sinus after repeated swallowing seen in VF correlated significantly with symptoms related to the pharyngeal phase (Spearman's rho 0.356-0.544). Conclusion. Because oropharyngeal dysphagia in DMD was evident in teenage patients as well as those without clinical symptoms, VF is recommended in patients with DMD.

Objective: To develop a short version of the motor Functional Independence Measure (FIM™) for use in long-term care settings. Participants: For model construction, the participants were 398 community-dwelling persons with disability (mean age 79.3 years (SD 10.3)) who were receiving visiting nurse services. For cross-validation, 169 patients with stroke (mean age 78.0 years (SD 11.2)) in the chronic phase and 187 patients with stroke (mean age 63.4 years (SD 12.7)) in the recovery phase. Design: Model construction and cross-validation study. Main outcome measures: The second power of correlation coefficient (R 2) was used for agreement analysis between the short and the full version. Cross-validation of the models was estimated with the intraclass correlation coefficient (ICC). Results: Five to 7 motor FIM™ items were selected for the models based on Rasch calibration and consideration of internal consistency. Total motor FIM™ was estimated with the 6-item and 7-item models with regression analysis, which yielded high correlations with the original 13-item motor FIM™ score (R2>0.95). Regression formulas derived from the models could estimate total motor FIM™ scores accurately in the 2 cross-validation samples (ICC>0.98). Conclusion: The short version of the motor FIM™ developed is a useful measure of functional status, not only in long-term care but in the recovery phase rehabilitation settings. © 2006 Taylor & Francis.

Older adults who have survived cancer experience significantly more falls compared with healthy adults. Adult cancer survivors may also have a lower balance function than healthy adults. We examined muscle strength and balance function among 19 cancer survivors and 14 healthy subjects. The mean age of the cancer survivors was 51.5 ± 11.2 years; 6 men and 13 women. Cancer diagnoses included breast cancer, retroperitoneal sarcoma, acute leukemia, lung cancer, colorectal cancer, thyroid cancer, Ewing's sarcoma, and tongue cancer. The mean age of healthy subjects was 47.4 ± 14 years; 3 men, 11 women. Muscle strength was assessed using hand grip and knee extensor strength tests. Balance function was evaluated using the Timed Up and Go (TUG) test, and body sway was tested using a force platform. No significant differences were found with respect to right and left grip strength or right and left knee extension strength between the 2 groups. A significantly higher TUG time was observed in cancer survivors than in healthy subjects ( P < .05). With eyes open, the area of the center of pressure was significantly larger in cancer survivors than in healthy subjects ( P < .05). Similarly, the length per area was significantly lower both with eyes open and closed for cancer survivors than for healthy subjects ( P < .05). TUG was significantly correlated with muscle strength in both groups ( P < .05). However, no body sway parameters were related to muscle strength in either group. Cancer survivors had lower balance function that might not have been related to muscle strength. Cancer survivors should be evaluated for balance function as there is a potential for impairment. The findings of this study will be relevant for planning the prevention of falls for cancer survivors.

Background : Walking disability caused by central nervous system injury often lingers. In the chronic phase, there is great need to improve walking speed and gait, even for patients who walk independently. Robot-assisted gait training (RAGT) has been widely used, but few studies have focused on improving gait patterns, and its effectiveness for motor function has been limited. This report describes the combination of “RAGT to learn the gait pattern” and “ankle robot training to improve motor function” in a patient with chronic stage brain injury.Case : A 34-year-old woman suffered a traumatic brain injury 5 years ago. She had residual right hemiplegia [Fugl-Meyer Assessment-Lower Extremity (FMA-LE): 18 points] and mild sensory impairment, but she walked independently with a short leg brace and a cane. Her comfortable gait speed was 0.57 m/s without an orthosis, and her 6-m walk test distance was 240 m. The Gait Assessment and Intervention Tool (G.A.I.T.) score was 35 points. After hospitalization, ankle robot training was performed daily, with RAGT performed 10 times in total. Post-intervention evaluation performed on Day 28 showed: FMA-LE, 23 points; comfortable walking speed, 0.69 m/s; G.A.I.T., 27 points; and three-dimensional motion analysis showed ankle dorsiflexion improved from 3.22° to 12.59° and knee flexion improved from 1.75° to 16.54° in the swing phase.Discussion : This is one of few studies to have examined the combination of two robots. Combining the features of each robot improved the gait pattern and motor function, even in the chronic phase.

BACKGROUND: Despite the lack of clinically validated strategies for treating spinal cord injury (SCI), combining therapeutic strategies with rehabilitation is believed to promote recovery of motor function; however, current research findings are inconsistent. OBJECTIVES: To explore whether combination therapy involving therapy and rehabilitative training (CIRT) has a synergistic effect on motor function recovery in animal models of SCI. METHODS: We conducted a systematic review and meta-analysis of studies identified in a keyword search of 6 databases and extracted open-field motor scores from the Basso Mouse Scale (BMS) and the Basso, Beattie, and Bresnahan Locomotor Rating Scale (BBB) for meta-analysis using a weighted mean difference (WMD) and 95 % CI. We also performed qualitative synthesis and analysis of secondary outcome measures related to histological improvements and adverse effects. RESULTS: Eighty-seven preclinical studies were included. Combination treatment with treadmill training resulted in a significant improvement in motor function (1.40, 95 % CI 0.82 to 1.98, P < 0.01, I2 = 49 %), especially when initiated 1-2 weeks post-injury (1.77, 95 % CI 1.10 to 2.45, P < 0.01, I2 = 33 %) in rats. In mice, CIRT lasting <6 weeks may enhance recovery (0.95, 95 % CI 0.49 to 1.40, P < 0.01, I2 = 33 %). Although there is a trend toward better outcomes in the chronic phase, insufficient sample sizes prevent definitive conclusions from being drawn. Combined therapy also enhances the reorganization of inhibitory synaptic structures and functions, without aggravating allodynia or spasticity. CONCLUSIONS: This systematic review and meta-analysis suggest that CIRT can lead to superior motor function recovery compared to single-modality therapy (SMT) in animal models of SCI, with no significant adverse effects on allodynia or spasticity. However, the efficacy of CIRT depends on various factors, and further research is needed to establish optimal treatment strategies and understand the underlying mechanisms of recovery.

Abstract Post-stroke disability affects patients’ lifestyles after discharge, and it is essential to predict functional recovery early in hospitalization to allow time for appropriate decisions. Previous studies reported important clinical indicators, but only a few clinical indicators were analyzed due to insufficient numbers of cases. Although review articles can exhaustively identify many prognostic factors, it remains impossible to compare the contribution of each predictor. This study aimed to determine which clinical indicators contribute more to predicting the functional independence measure (FIM) at discharge by comparing standardized coefficients. In this study, 980 participants were enrolled to build predictive models with 32 clinical indicators, including the stroke impairment assessment set (SIAS). Trunk function had the most significant standardized coefficient of 0.221. The predictive models also identified easy FIM sub-items, SIAS, and grip strength on the unaffected side as having positive standardized coefficients. As for the predictive accuracy of this model, R2 was 0.741. This is the first report that included FIM sub-items separately in post-stroke predictive models with other clinical indicators. Trunk function and easy FIM sub-items were included in the predictive model with larger positive standardized coefficients. This predictive model may predict prognosis with high accuracy, fewer clinical indicators, and less effort to predict.