土山 和大

Ankle-foot orthosis (AFO) is known to correct abnormal gait patterns and improve walking stability and speed in patients with hemiparesis. To quantify these benefits in post-stroke gait, a three-dimensional motion analysis of gait pattern was conducted. Forty patients with hemiparesis were enrolled. A three-dimensional motion analysis system was used to analyze patients' treadmill walking with/without an AFO. Outcome measures were 12 abnormal gait indices (forefoot contact, knee extensor thrust, retropulsion of the hip, flexed-knee gait, medial whip in the stance phase, circumduction gait, hip hiking, insufficient knee flexion during the swing phase, excessive lateral shifting of the trunk, contralateral vaulting, excessive hip external rotation, and posterior pelvic tilt), calculated using kinematic data and spatiotemporal indices, and the symmetry index of double-stance and single-stance time and step length. Forefoot contact (without AFO vs. with AFO: 71.0 vs. 65.8, P < 0.001), circumduction gait (65.0 vs. 57.9, P < 0.001), and contralateral vaulting (78.2 vs. 72.2, P = 0.003) were significantly reduced, whereas excessive hip external rotation (53.7 vs. 62.8, P = 0.003) significantly increased during walking with an AFO. Hip hiking (77.1 vs. 71.7) showed marginal reduction with the use of AFO ( P = 0.096). The absolute symmetry index of double-stance time (21.9 vs. 16.1, P = 0.014) significantly decreased during walking with an AFO. AFO effectively mitigates abnormal gait patterns typical of hemiparetic gait. A 3D motion analysis system with clinically oriented indices can help assess intervention efficacy for gait abnormalities.

Objectives: To evaluate the safety and acceptability of a newly developed tele-rehabilitation exercise system using computer-generated animation. Methods: The participants comprised a convenience sample of 38 diverse individuals in Experiment 1 (15 healthy young people, 16 healthy older people, 5 patients with stroke, and 2 patients with respiratory disease) and 18 healthy older individuals in Experiment 2. Experiment 1 assessed safety in terms of cardiopulmonary vascular aspects and risk of fall, and Experiment 2 assessed treatment acceptability via a subjective evaluation. All participants completed the same exercise program. The safety assessment was conducted using heart rate (HR) and saturation of percutaneous oxygen (SpO2), measured before and after exercise. In addition, the occurrence of falls was assessed. For the acceptability assessment, the participants answered five questions (three-point Likert scale) after the exercise program. Results: The safety assessment indicated that HR and SpO2 changed from 70.5±10.2 beats per minute and 97.8±1.3% before exercise to 87.6±13.6 beats per minute and 98.2±0.9% after exercise, respectively. In addition, all participants completed the exercises without experiencing any falls. In the acceptability assessment, the score reflecting continuation desire was the highest of the five items examined (2.71±0.46). In contrast, the adequacy of exercise intensity had the lowest score (1.29±0.57). Conclusions: The present system was confirmed to be safe, and the participants were motivated to continue the exercises. Future developments should incorporate a function to enable participants and medical staff to adjust exercise intensity according to individual physical function.

BACKGROUND: Ankle-foot orthoses are used to improve gait stability in patients with post-stroke gait; however, there is not enough evidence to support their beneficial impact on gait stability. AIM: To investigate the effects of ankle-foot orthoses on post-stroke gait stability. DESIGN: An experimental study with repeated measurements of gait parameters with and without orthosis. SETTING: Inpatients and outpatients in the Fujita Health University Hospital. POPULATION: Thirty-two patients (22 males; mean age 48.3±20.0 years) with poststroke hemiparesis participated in the study. METHODS: Three-dimensional treadmill gait analysis was performed with and without ankle-foot orthosis for each participant. Spatiotemporal parameters, their coefficient of variation, and margin of stability were evaluated. Toe clearance, another major target of orthosis, was also examined. The effect of orthosis in the patients with severe (not able to move within the full range of motion, defying gravity) and mild ankle impairment (able to move within the full range but have problem with speed and/or smoothness of the ankle movement) was compared. RESULTS: In the total group comparison, the decrease in the coefficient of variation of step width (P=0.012), and margin of stability on the paretic side (P=0.023) were observed. In the severe ankle impairment groups, the decreased in the coefficient of variation of the non-paretic step length (P=0.007), stride length (P=0.037), and step width (P=0.033) and margin of stability on the paretic side (P=0.006) were observed. No significant effects were observed in the mild ankle impairment group; rather, the coefficient of variation of non-paretic step length increased with the use of orthosis in this group (P=0.043); however, toe clearance increased with the use of ankle-foot orthosis (P=0.041). CONCLUSIONS: Ankle-foot orthoses improved gait stability indices; however, the effect was either not significant or showed possible worsening in the patients with mild ankle impairment, while the effect on toe clearance was significant. These results suggest that the effects of using orthoses in patients with mild impairment should be carefully evaluated. CLINICAL REHABILITATION IMPACT: Understanding the effects of ankle-foot orthoses on the stability of post-stroke gait and their relationship with ankle impairment severity may support clinical decision-making while prescribing orthosis for post-stroke hemiparesis.

Hemiparesis resulting from stroke presents characteristic spatiotemporal gait patterns. This study aimed to clarify the spatiotemporal gait characteristics of hemiparetic patients by comparing them with height-, speed-, and age-matched controls while walking at various speeds. The data on spatiotemporal gait parameters of stroke patients and that of matched controls were extracted from a hospital gait analysis database. In total, 130 pairs of data were selected for analysis. Patients and controls were compared for spatiotemporal gait parameters and the raw value (RSI) and absolute value (ASI) of symmetry index and coefficient of variation (CV) of these parameters. Stroke patients presented with prolonged nonparetic stance (patients vs. controls: 1.01 ± 0.41 vs. 0.83 ± 0.25) and paretic swing time (0.45 ± 0.12 vs. 0.39 ± 0.07), shortened nonparetic swing phase (0.35 ± 0.07 vs. 0.39 ± 0.07), and prolonged paretic and nonparetic double stance phases [0.27 ± 0.13 (paretic)/0.27 ± 0.17 (nonparetic) vs. 0.22 ± 0.10]. These changes are especially seen in low-gait speed groups (<3.4 km/h). High RSIs of stance and swing times were also observed (-9.62 ± 10.32 vs. -0.79 ± 2.93, 24.24 ± 25.75 vs. 1.76 ± 6.43, respectively). High ASIs and CVs were more generally observed, including the groups with gait speed of ≥3.5 km/h. ASI increase of the swing phase (25.79 ± 22.69 vs. 4.83 ± 4.88) and CV of the step length [7.7 ± 4.9 (paretic)/7.6 ± 5.0 (nonparetic) vs. 5.3 ± 3.0] were observed in all gait speed groups. Our data suggest that abnormalities in the spatiotemporal parameters of hemiparetic gait should be interpreted in relation to gait speed. ASIs and CVs could be highly sensitive indices for detecting gait abnormalities.

Background: Ankle-foot orthoses (AFOs) are frequently used to improve gait stability, toe clearance, and gait efficiency in individuals with hemiparesis. During the swing phase, AFOs enhance lower limb advancement by facilitating the improvement of toe clearance and the reduction of compensatory movements. Clinical monitoring via kinematic analysis would further clarify the changes in biomechanical factors that lead to the beneficial effects of AFOs. The purpose of this study was to investigate the actual impact of AFOs on toe clearance, and determine the best strategy to achieve toe clearance (including compensatory movements) during the swing phase. Methods: This study included 24 patients with hemiparesis due to stroke. The gait performance of these patients with and without AFOs was compared using three-dimensional treadmill gait analysis. A kinematic analysis of the paretic limb was performed to quantify the contribution of the extent of lower limb shortening and compensatory movements (such as hip elevation and circumduction) to toe clearance. The impact of each movement related to toe clearance was assessed by analyzing the change in the vertical direction. Results: Using AFOs significantly increased toe clearance (p = 0.038). The quantified limb shortening and pelvic obliquity significantly differed between gaits performed with versus without AFOs. Among the movement indices related to toe clearance, limb shortening was increased by the use of AFOs (p &lt 0.0001), while hip elevation due to pelvic obliquity (representing compensatory strategies) was diminished by the use of AFOs (p = 0.003). The toe clearance strategy was not significantly affected by the stage of the hemiparetic condition (acute versus chronic) or the type of AFO (thermoplastic AFOs versus adjustable posterior strut AFOs). Conclusions: Simplified three-dimensional gait analysis was successfully used to quantify and visualize the impact of AFOs on the toe clearance strategy of hemiparetic patients. AFO use increased the extent of toe clearance and limb shortening during the swing phase, while reducing compensatory movements. This approach to visualization of the gait strategy possibly contributes to clinical decision-making in the real clinical settings. Trial registration: UMIN000028946. Registered 31 August 2017 (retrospectively registered).

Although a posturography is commonly used for objective evaluation of static balance function, dynamic balance function is usually evaluated only with clinical scales. Simplified objective measurement systems for the evaluation of dynamic balance function need to be developed. In this preliminary study, we attempted to develop an index for the objective measurement of dynamic balance function from COP-COG data. The subjects comprised nine hemiparetic post-stroke patients and five healthy subjects. The simultaneous measurements of COG and COP were performed using a three-dimensional motion analysis system (Kinematracer, KisseiComtec, Japan) combined with force plate analysis. As indices for evaluating dynamic balance function, the latency of COP passing COG after heel contact (LCP) and the averaged |COP| -|COG| subtraction value during stance phase (ASV) were calculated. For evaluating validity of the measurement, the Berg Balance Scale, a frequently used clinical balance scale, was used. The results showed significant differences (0.13 +/- 0.02 vs. 0.29 +/- 0.23 s) between the healthy subjects and patients in LCP, and large, yet insignificant, differences (4.3 +/- 0.5 vs. 2.7 +/- 2.0 cm) in ASV. The ASV was strongly correlated with BBS. A strong correlation was observed between COG acceleration and ASV, except in one patient, who had a severe balance disorder. These results may encourage further investigation into the feasibility of COP-COG measurements for balance measurement.

Background: The toe clearance of a paretic limb in the swing phase of gait is related to tripping, which is considered a major cause of falls. The biomechanical factors for obtaining toe clearance are more complicated in hemiparetic gait than that in normal gait because of the compensatory movements during swing phase. Understanding the biomechanical factors should help in targeting the point for rehabilitative interventions. Objective: To clarify the biomechanical factors behind toe clearance during swing phase in hemiparetic gait. Methods: Fifty patients with hemiparesis after a stroke participated in this study. Three-dimensional motion analysis was used for the kinematic analysis of the hemiparetic gait. The correlation coefficients between limb shortening and angle changes and between limb shortening and hip elevation and foot lateral shift were calculated. Limb shortening was defined as the shortening of the hip-toe distance. The significant factors that determine toe clearance were examined by multiple regression analysis. Independent variables were limb shortening, hip elevation, and foot lateral shift. Results: Limb shortening was negatively correlated with hip elevation (r = -0.75) and foot lateral shift (r = -0.41). Multiple regression analysis showed a significant contribution of limb shortening and hip elevation to toe clearance. The coefficient of determination was 0.95. Conclusions: Toe clearance was mainly determined by limb shortening and hip elevation, which were found to be in a trade-off relationship. These results warrant further investigation into the use of three-dimensional motion analysis in the rehabilitation clinic to facilitate targeted rehabilitative training to restore gait ability.

OBJECTIVE: Although previous studies have evidenced the value of three-dimensional gait analysis (3DGA) for evaluating gait disorder, the time-consuming measurement process and space requirement has hampered its use in the clinical setting. The aim of this study was to examine the feasibility of a simplified 3DGA system for stroke patients. METHODS: Thirteen pairs of stroke patients and age- (± 1 year), gender-, and gait speed- (± 0.5 m/s) matched controls were drawn from the Fujita Health University gait analysis database. 3DGA was performed using the KinemaTracer® treadmill gait analysis system. Comparisons of the spatiotemporal and kinematic parameters were performed between stroke patients and matched controls. The correlations between items from the Wisconsin Gait Scale (WGS) and 3DGA data in stroke patients were also investigated. RESULTS: 3DGA measurements clearly showed reduced toe clearance, hip flexion, and knee flexion in stroke patients compared with the matched controls. In contrast, significant increases were observed in hip elevation, shoulder elevation, shoulder lateral shift, and step width in stroke patients. For the four items drawn from the WGS, a significant correlation with three 3DGA parameters was observed: stance time on the impaired side, stance width, and knee flexion from toe off to midswing. CONCLUSIONS: In this study, significant differences in gait parameters of stroke patients and age-, gender-, and speed-matched controls were found using a simplified 3DGA system. A significant correlation with WGS was also observed. These results support the validity of the clinical measurement of gait parameters using a simplified 3DGA system.

<p>Pongpipatpaiboon K, Mukaino M, Tsuchiyama K, Ohtsuka K, Matsuda F, Tanikawa H, Yamada J, Saitoh E. The use of a holistic figure in gait analysis: a preliminary study on the effect of ankle-foot orthosis. Jpn J Compr Rehabil Sci 2016; 7: 80-86.</p><p>Objective: To examine the practical usefulness of a simplified three-dimensional treadmill gait analysis with a Lissajous overview picture (LOP), a holistic figure of marker trajectories, to present the effect of ankle-foot orthoses (AFO) on hemiparetic gait.</p><p>Methods: Seven patients with hemiparesis who were able to walk without an orthosis or gait assistive device were included in this study. Patients were measured with a simplified three-dimensional treadmill gait analysis system as they walked with and without an orthosis in a rehabilitation center of a university medical center. Gait was analyzed using the LOP, and quantitative comparisons were made to evaluate the changes in joint angles and joint position displacements during the swing phase.</p><p>Results: Using the orthosis decreased ankle plantar flexion during the swing phase (p = 0.028) and significantly reduced compensatory patterns, including hip elevation, knee elevation, and circumduction (p = 0.028, 0.018, and 0.028, respectively).</p><p>Conclusions: The quantitative assessment by a simplified gait analysis system clarified the effect of AFO on reducing the compensatory movement in a hemiparetic gait. The use of LOP helps to understand the holistic effect of AFO and to analyze the individual patterns of gait disturbance.</p>