Diverse Plantarflexor Module Characteristics Influence Immediate Effects of Plastic Ankle-Foot Orthosis on Gait Performance in Patients With Stroke: A Cross-sectional Study.

OBJECTIVE: To investigate the immediate effects of plastic ankle-foot orthosis (AFO) on locomotor performance in patients with stroke and determine how such effects might undergo alteration when distinct plantarflexor (PF) module subtypes are considered. DESIGN: Cross-sectional study. SETTING: Two university hospitals. PARTICIPANTS: Fifty-two patients with stroke and 21 of those without stroke (N=73). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Motor modules were identified through non-negative matrix factorization, and participants were classified into 3 groups: independent-normal-timing, independent-altered-timing, and merged PF modules. To assess the effects of the AFO, gait measurements reflecting locomotor performance were obtained with and without the presence of the plastic AFO for each group. RESULTS: The independent-altered-timing group had increased paretic propulsion, greater non-paretic step length, and faster walking speed after the administration of the plastic AFO; however, these significant changes were not observed in the independent-normal-timing and merged PF module groups. Notably, patients in the independent-normal-timing and merged PF module groups exhibited longer paretic stance times. CONCLUSION: This study suggests that the immediate effects of plastic AFO depend on the PF module subtype. These findings can potentially guide clinical decision-making regarding AFO selection for stroke rehabilitation in patients with diverse gait control characteristics.

Investigation of a practical assessment index to capture the clinical presentation of cachexia in patients with lung cancer.

OBJECTIVE: Cancer cachexia constitutes a poor prognostic factor in patients with lung cancer. However, the factors associated with cancer cachexia remain unclear. This study aimed to identify factors that influence cancer cachexia in patients with lung cancer. METHODS: In this retrospective observational study conducted at the Kansai Medical University, 76 patients with lung cancer were evaluated for physical function, nutritional status (Mini Nutritional Assessment-Short Form) and physical activity (International Physical Activity Questionnaire-Short Form) at the first visit to the rehabilitation outpatient clinic. The patients were divided into cachexia and noncachexia groups. The log-rank tests and Cox proportional hazards model were used to investigate the relationship between cachexia and prognosis. To examine the factors that influence cachexia, multivariate regression analysis with significant (P < 0.05) variables in the univariate logistic regression analysis was performed. Spearman's correlation analysis was performed to investigate the association between International Physical Activity Questionnaire-Short Form and performance status. RESULTS: Overall, 42 patients (55.2%) had cachexia associated with survival time since their first visit to the outpatient rehabilitation clinic, even after confounders adjustment (hazard ratio: 3.24, 95% confidence interval: 1.12-9.45, P = 0.031). In the multivariate analysis, Mini Nutritional Assessment-Short Form (odds ratio: 20.34, 95% confidence interval: 4.18-99.02, P < 0.001) and International Physical Activity Questionnaire-Short Form (odds ratio: 4.63, 95% confidence interval: 1.20-17.89, P = 0.026) were identified as independent factors for cachexia. There was no correlation between International Physical Activity Questionnaire-Short Form and performance status (r = 0.155, P = 0.181). CONCLUSION: Malnutrition and low physical activity were associated with cachexia in patients with lung cancer. The International Physical Activity Questionnaire-Short Form may be a useful indicator of physical activity in cachexia. Regularly assessing these factors and identifying suitable interventions for cachexia remain challenges to be addressed in the future.

Use of the reliable change index to evaluate the effect of a multicomponent exercise program on physical functions.

AIMS: Using the reliable change index (RCI), we aimed to examine the effect of a multicomponent exercise program on the individual level. METHODS: Overall, 270 adults (mean age, 78 years) completed a multicomponent physical exercise program (strength, aerobic, gait, and balance) for 40 min, 1-2 times per week, continued up to 1 year at a daycare center. Effectiveness was assessed using grip, ankle, knee, and hip strength; Timed Up & Go (TUG); Berg Balance Scale (BBS); gait speed; and 6-min walking distance. These were measured at baseline and every 3 months thereafter. We calculated the RCI using the data between two-time points (baseline and at 3, 6, 9, or 12 months) in each participant and then calculated the mean RCI value across the participants. A paired t-test was also employed to evaluate the effect of the intervention as an average-based statistics. RESULTS: The highest mean RCI values were on ankle plantar-flexion strength, followed by gait speed, hip abduction strength, BBS, knee extensor strength, 6-min walk distance, grip strength, and finally TUG. Paired t-test also revealed significant improvement with moderate effect sizes for ankle plantar-flexion strength (0.504), gait speed (0.413), hip abduction strength (0.374), BBS (0.334), knee extensor strength (0.264), and 6-min walk distance (0.248). Significant but small effect size was seen on TUG (0.183). CONCLUSION: The RCI is a convenient method of comparing the effect between different assessments, especially at an individual level. This index can be applied to the use of personal feedback.

How to Decide the Number of Gait Cycles in Different Low-Pass Filters to Extract Motor Modules by Non-negative Matrix Factorization During Walking in Chronic Post-stroke Patients.

The motor modules during human walking are identified using non-negative matrix factorization (NNMF) from surface electromyography (EMG) signals. The extraction of motor modules in healthy participants is affected by the change in pre-processing of EMG signals, such as low-pass filters (LPFs); however, the effect of different pre-processing methods, such as the number of necessary gait cycles (GCs) in post-stroke patients with varying steps, remains unknown. We aimed to specify that the number of GCs influenced the motor modules extracted in the consideration of LPFs in post-stroke patients. In total, 10 chronic post-stroke patients walked at a self-selected speed on an overground walkway, while EMG signals were recorded from the eight muscles of paretic lower limb. To verify the number of GCs, five GC conditions were set, namely, 25 (reference condition), 20, 15, 10, and 5 gate cycles with three LPFs (4, 10, and 15 Hz). First, the number of modules, variability accounted for (VAF), and muscle weightings extracted by the NNMF algorithm were compared between the conditions. Next, a modified NNMF algorithm, in which the activation timing profiles among different GCs were unified, was performed to compare the muscle weightings more robustly between GCs. The number of motor modules was not significantly different, regardless of the GCs. The difference in VAF and muscle weightings in the different GCs decreased with the LPF of 4 Hz. Muscle weightings in 15 GCs or less were significantly different from those in 25 GCs using the modified NNMF. Therefore, we concluded that the variability extracted motor modules by different GCs was suppressed with lower LPFs; however, 20 GCs were needed for more representative extraction of motor modules during walking in post-stroke patients.

Longitudinal effects of physical exercise on health-related outcomes based on frailty status in community-dwelling older adults.

AIM: To clarify the difference in the longitudinal effects of physical exercise on health-related outcomes according to the baseline frailty status (frail or non-frail) in community-dwelling older adults. METHODS: Participants included 177 adults aged ≥65 years who carried out multicomponent physical exercises (strength, aerobic, gait and balance) for 40 min, one to three times per week, for 1 year at a day-care center. Bodyweight, comfortable walking speed, 6-min walking distance and Mini-Mental State Examination were measured at baseline and every 3 months. For longitudinal trend, we analyzed the change in scores from baseline for each outcome using the linear mixed effects model. Fixed effects included "group" (frail or non-frail), "time" (4 time points every 3 months, from 3 to 12 months) and "interaction between group and time." RESULTS: The effect sizes from baseline showed almost all positive values for each outcome. The linear mixed effects model showed significant effects on "interaction between group and time" in changes in bodyweight (P = 0.033), "group" in changes in walking speed (P = 0.013) and "time" in changes in the Mini-Mental State Examination (P < 0.001). Bodyweight showed a decreasing trend in the non-frail group after 3 months, unlike in the frail group. For walking speed, moderate effect sizes (d = 0.67-0.74) were sustained over time in the frail group, as did lesser effect sizes (d = 0.26-0.40) in the non-frail group. CONCLUSIONS: Exercise-based multicomponent interventions were effective for both groups. The longitudinal effects on walking speed and bodyweight were greater in the frail group. Geriatr Gerontol Int 2022; 22: 213-218.

Current perspectives on quantitative gait analysis for patients with hemiparesis.

Hase K. Current perspectives on quantitative gait analysis for patients with hemiparesis. Jpn J Compr Rehabil Sci 2022; 13: 1-3.

Long-term effects of combined botulinum toxin treatment and rehabilitation on upper limb muscle spasms: a case report.

[Purpose] We report our experience with a patient with a central spinal cord injury who showed improved finger and upper limb functions after long-term treatment with a combination of rehabilitation and botulinum toxin type A. [Participants and Methods] The patient had spasms and pain that gradually became more profound and was given botulinum toxin type A at 1 year 3 months after sustaining a spinal cord injury. We administered 14 botulinum toxin type A injections periodically for 7 years 4 months after the injury. We administered the injections at an average interval of 5.6 months. Splints that allowed extension and improved finger muscle tone and contracture were made for the patient. [Results] The patient experienced gradual alleviation of the spasms in the proximal upper limb muscles and improved range of motion after receiving five doses of botulinum toxin type A. The spasms and range of motion in the fingers gradually improved around 4 years after the injury through splint therapy and a combination of botulinum toxin type A administration and rehabilitation. [Conclusion] The combination of botulinum toxin type A, splint, and rehabilitation therapies can lead to positive improvements in finger spasticity and range of motion and is recommended for hypertonia cases with severe contractures.

A Cross-Sectional Study on the Association between Body Mass Index and Frailty According to Sex in Elderly Patients with Disabilities from an Elderly Day-Care Center.

The association between body mass index (BMI) and frailty in elderly patients with disabilities is unclear. We aimed to investigate the association between BMI and frailty in the elderly with disabilities according to sex. This cross-sectional study included 280 elderly patients with disabilities from an elderly daycare center. BMI classification for the Asian population was used to categorize the patients into four groups: underweight, normal, overweight, and obese. Frailty score was based on the phenotypic definition of frailty and consisted of five criteria derived from the revised Japanese version of the Cardiovascular Health Study. Those who had three or more criteria were considered frail. Logistic regression models were constructed to investigate the associations between frailty and BMI in each group (males and females). In females, being underweight was significantly associated with frailty after adjusting for confounders (age and Mini-Mental State Examination score); after adding medical history as a confounder, the aforementioned association was not significant. In males, BMI was not significantly associated with frailty. The association between BMI and frailty differed according to sex among the elderly with disabilities. This finding provides important information regarding frailty risk to workers in daycare facilities.

Novel characterization of subjective visual vertical in patients with unilateral spatial neglect.

Visual vertical (VV), visually perceived direction of gravity, is widely measured to assess the vestibular function and visuospatial cognition. VV has been assessed by comparing orientation and variability of measured values separately between subject groups. However, changes in orientation and variability often differ in patients with unilateral spatial neglect (USN). Here, we developed a novel classification of VV that combines orientation and variability and characterized the effects of USN on VV. Forty-three subacute stroke patients with or without USN (USN+, n = 17; USN-, n = 26) and 33 age-matched controls were included in the study. In darkness, a luminous line, initially tilted at 30° either to the left or right, gradually rotated towards the vertical. The VV was defined as the deviation of the subjectively-perceived vertical from the true vertical. The new classification demonstrated that, while the majority of USN + patients (14/17) exhibited large variability, nine showed normal orientation and five showed greater contra-lesional deviation of orientation, suggesting different underlying mechanisms for orientation and variability. Further analyses revealed VV deviation to the initial tilt in all groups. However, the deviation in USN + was larger and more variable, indicating attentional disorders. Such characterization would contribute to individually specified clinical rehabilitation.

Immediate Effect on Ground Reaction Forces Induced by Step Training Based on Discrete Skill during Gait in Poststroke Individuals: A Pilot Study.

METHODS: Twenty-two community-dwelling patients with chronic hemiplegia participated in this study. Eight participants performed only discrete-skill step training during the loading response phase, focusing on paretic hip extension movement (LR group). Another eight performed only discrete-skill step training during the preswing phase, focusing on paretic swing movement (PSw group). The remaining six were trained using both training methods, with at least 6 months in each group to washout the influence of previous training. Therefore, the final number of participants in each group was 14. The braking and propulsive forces of GRFs were measured during gait before and after 30 repetitions of the discrete-skill step training. RESULTS: Although both groups showed a significant increase in stride length, walking speed was increased only in the LR group. The PSw group showed an increase in braking forces of both sides without any change in propulsion. In the LR group, paretic braking impulse did not change, while nonparetic propulsion increased. CONCLUSION: The discrete-skill step training during loading response phase induced an increase in nonparetic propulsion, resulting in increased walking speed. This study provides a clear understanding of immediate effects of the discrete-skill step training in patients with chronic stroke and helps improve interventions in long-term rehabilitation.

Relationship between vertical ground reaction force and muscle strength while climbing stairs after total hip arthroplasty.

BACKGROUND: Little is known about the relationship between vertical ground reaction force (vGRF) and muscle strength while climbing stairs after total hip arthroplasty (THA). METHODS: We investigated the relationship between muscle strength and vGRF during stair climbing in 21 women with THA. Differences in the time required to climb stairs and side-to-side differences in muscle strength and vGRF during climbing were examined at 6 and 12 months. The relationship between climbing time and vGRF variables and that between vGRF and muscle strength were analyzed using Spearman's rank correlation coefficient at 6 and 12 months. First peak force (Fz1) was defined as the peak vGRF at heel strike normalized by body weight. FINDINGS: Climbing time was related to the time to Fz1 at 6 and 12 months post-THA (r = 0.50-0.64). At 6 months, time to Fz1 was related to the strength of muscles involved in hip extension in the operated limb (r = -0.46). At 12 months, time to Fz1 was related to the strength of muscles responsible for knee extension in the operated limb (r = -0.45). INTERPRETATION: At 6 months, climbing stairs depended on muscle strength in the hip extensors. Conversely, at 12 months, the functional recovery of knee extensors was important for transferring weight upward while climbing stairs. Therefore, to improve the climbing function of patients with THA, it is important to not only focus on the recovery of muscle strength in the hip extensors but also improve muscle strength in the knee extensors.

Potential of muscles to accelerate the body during late-stance forward progression in individuals with knee osteoarthritis.

Many individuals with knee osteoarthritis (OA) generate low forward center of mass (COM) acceleration during the late stance phase, consequently making it difficult to walk fast. This study analyzed individual muscle contributions to forward COM acceleration and the muscle potential (i.e., acceleration by unit force) to clarify whether reduced acceleration was related to decreased muscle potential of forward progression by the triceps sure. Twelve individuals with knee OA and 12 healthy age-matched individuals participated in this study. All participants underwent kinetic measurements during normal gait. The simulation involved 92 Hill-type muscle-tendon units with 23 degrees of freedom. We analyzed how each muscle contributed to forward COM acceleration during the 70-100% stance phase using an induced acceleration analysis. Next, the muscle potential of forward COM acceleration was calculated. Our results showed that individuals with knee OA had significantly lower forward COM acceleration with the soleus, gastrocnemius, and iliopsoas muscles compared with controls. Lower muscle potential in the soleus was found in those with knee OA. These findings implied that improving the contribution of the soleus to forward body progression would be effective for increasing the gait speed of those with knee OA during the late stance phase.

Muscle contributions to knee extension in the early stance phase in patients with knee osteoarthritis.

The aim of this study was to analyze individual muscle contributions to knee angular acceleration using a musculoskeletal simulation analysis and evaluate knee extension mechanics in the early stance phase in patients with knee osteoarthritis (OA). The subjects comprised 15 patients with medial knee OA and 14 healthy elderly individuals. All participants underwent gait performance test using 8 infrared cameras and two force plates to measure the kinetic and kinematic data. The simulation was driven by 92 Hill-type muscle-tendon units of the lower extremities and a trunk with 23° of freedom. We analyzed each muscle contribution to knee angular acceleration in the 5%-15% and 15%-25% periods of the stance phase (% SP) using an induced acceleration analysis. We compared accelerations by individual muscles between the two groups using an analysis of covariance for controlling gait speed. Patients with knee OA had a significantly lesser knee extension acceleration by the vasti muscles and higher knee acceleration by hip adductors than those in controls in 5-15% SP. In addition, knee OA resulted in significantly lesser knee extension acceleration by the vasti muscles in 15-25% SP. These results indicate that patients with knee OA have decreased dependency on the vasti muscles to control knee movements during early stance phase. Hip adductor muscles, which mainly control mediolateral motion, partly compensate for the weak knee extension by the vasti muscles in patients with knee OA.

Validity and reliability of a performance evaluation tool based on the modified Barthel Index for stroke patients.

BACKGROUND: The Barthel Index (BI) is a measure of independence in activities of daily living (ADL). In the modified Barthel Index (MBI), a five-point system replaced the original two or three or four point rating system. Based on this modified measure, the performance evaluation tool MBI (PET-MBI) was developed in Japan. Although the reliability and validity of PET-MBI have been verified for older people, the use of this tool in stroke patients has not been evaluated. This study investigated the validity and reliability of PET-MBI for stroke patients. METHODS: Ten raters independently determined the BI and PET-MBI scores of stroke patients by direct observation. These patients' ADL were videotaped, and 10 other raters then evaluated the videos privately and assigned PET-MBI scores twice, one month apart. The criterion-related validity of the PET-MBI against the BI was evaluated using the correlation coefficients for their total scores. Furthermore, to assess inter- and intra-rater reliabilities from the results of the first and second sessions, Fleiss' intraclass correlation coefficients (ICCs) were calculated for the total scores, with the lower limits of the 95% confidence interval (95%CI), along with weighted kappa (κw) coefficients for agreement in individual tasks of this evaluation tool. ICC and κw coefficients of 0.81-1.00 were considered to be "almost perfect" agreement. RESULTS: The mean age of the 30 patients (23 men, 7 women) was 71.9 (standard deviation 10.5) years. One patient had diplegia, 14 had right hemiplegia, and 15 had left hemiplegia. For the total scores obtained by direct evaluation, Pearson's and Spearman's correlation coefficients of the BI versus the PET-MBI were both 0.95 (lower limit of the 95%CI, 0.90). The ICC representing inter-rater reliability for the first session was 0.99 (lower limit of the 95%CI, 0.98]. For intra-rater reliability, the mean value of the ICCs was 0.99 (range, 0.99-1.00). For individual tasks of the PET-MBI, inter-rater κw coefficients for the first session ranged from 0.77 to 0.94, with intra-rater κw coefficients from 0.85 to 0.96. CONCLUSIONS: PET-MBI showed strong criterion-related validity against the BI, with high reliabilities. This scoring system may become a convenient tool allowing anyone to assess ADL.

Comparison of three instruments to assess changes of motor impairment in acute hemispheric stroke: the Stroke Impairment Assessment Set (SIAS), the National Institute of Health Stroke Scale (NIHSS) and the Canadian Neurological Scale (CNS).

PURPOSE: The purpose was to compare the performance of three representative instruments to measure changes of motor recovery with acute hemispheric stroke. METHOD: In 41 consecutive patients with acute hemispheric infarction, motor recovery was assessed within 3 days of onset and then every 2 weeks until the 12th week with the Stroke Impairment Assessment Set (SIAS), the National Institutes of Health stroke scale (NIHSS) and the Canadian Neurological Scale (CNS). We analyzed the relationships among the corresponding subscales of the three instruments with the Spearman's rank correlation method, and compared their responsiveness by plotting the temporal profiles of scores of each instrument and by testing the significance of changes over time with the Friedman test. RESULTS: High correlations were observed among the three instruments at each examination point. However, the SIAS scores were more widely dispersed at the same NIHSS and CNS scores. Friedman test revealed that the scores changed significantly during the observation period with the SIAS and the CNS but not with the NIHSS. The changes were detected later with the CNS than with the SIAS. CONCLUSIONS: Although the assessment results with the three instruments were highly inter-correlated, the SIAS performed better with respect to responsiveness to changes. Implication for Rehabilitation When providing rehabilitation services to patients with stroke, it is important to document objectively the level of their impairment from the acute stage and during the entire course of rehabilitation with standardized instrument, and to predict their functional outcomes as early and accurately as possible. This study therefore compared three representative instruments with established psychometric properties, the SIAS, the NIHSS and the CNS, with respect to their ability to document motor impairment and their responsiveness to recovery in patients with acute hemispheric stroke.

The effect of active pedaling combined with electrical stimulation on spinal reciprocal inhibition.

OBJECTIVE: Pedaling is widely used for rehabilitation of locomotion because it induces muscle activity very similar to locomotion. Afferent stimulation is important for the modulation of spinal reflexes. Furthermore, supraspinal modulation plays an important role in spinal plasticity induced by electrical stimulation. We, therefore, expected that active pedaling combined with electrical stimulation could induce strong after-effects on spinal reflexes. DESIGN: Twelve healthy adults participated in this study. They were instructed to perform 7 min of pedaling. We applied electrical stimulation to the common peroneal nerve during the extension phase of the pedaling cycle. We assessed reciprocal inhibition using a soleus H-reflex conditioning-test paradigm. The magnitude of reciprocal inhibition was measured before, immediately after, 15 and 30 min after active pedaling alone, electrical stimulation alone and active pedaling combined with electrical stimulation (pedaling + ES). RESULTS: The amount of reciprocal inhibition was significantly increased after pedaling + ES. The after-effect of pedaling + ES on reciprocal inhibition was more prominent and longer lasting compared with pedaling or electrical stimulation alone. CONCLUSIONS: Pedaling + ES could induce stronger after-effects on spinal reciprocal inhibitory neurons compared with either intervention alone. Pedaling + ES might be used as a tool to improve locomotion and functional abnormalities in the patient with central nervous lesion.

State of intracortical inhibitory interneuron activity in patients with chronic stroke.

OBJECTIVES: Few studies have assessed short intracortical inhibition (SICI) in the affected hemisphere (AH) in a large number of patients with chronic stroke. In this study, SICI was assessed in chronic stroke patients with severe hemiparesis, and its relationship to clinical parameters was examined. METHODS: The participants were 72 patients with chronic hemiparetic stroke. SICI of both the AH and the unaffected hemisphere (UH) was assessed. The relationships between SICI and the location of lesion, time from onset, and finger function were studied. Motor function of the paretic finger was assessed with the Stroke Impairment Assessment Set (SIAS) and the Fugl-Meyer test upper extremity motor score. To compare the results with those of healthy subjects, SICI was assessed in seven age-matched control subjects. RESULTS: MEPs of the UH were evoked in all 72 subjects, and MEPs of the AH were evoked in 24 subjects. SICI of the AH was inversely correlated with paretic finger motor function and time from stroke onset. SICI of the UH was not correlated with either one. SICI of the UH was higher in the cortical lesion group than in the control group. CONCLUSIONS: The state of intracortical inhibitory neuron activity depends on the state of motor function and lesion site even in chronic stroke patients with severe hemiparesis. SIGNIFICANCE: The inhibitory system of the AH is involved in functional recovery of the paretic hand even in the chronic stage of stroke.