The ReWalk^TM is a robotic exoskeleton orthosis that provides powered hip and knee motion to enable patients with spinal cord injury (SCI) to stand upright and walk with Lofstrand crutches. The built-in tilt sensor detects upper body motion and triggers steps. Users need to use crutches to maintain balance during standing and walking. Therefore, users need to learn and train themselves how to use it. After completing 20-hr basic training, users can stand, sit, turn and walk indoors. It is well-known that prolonged standing in people with SCI can improve and maintain mental, physical and social well-being. Wearable robotic exoskeletons are expected to afford people with SCI an opportunity to achieve prolonged walking and standing.

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The walking assist device was developed to enhance effective walking in older adults and patients with gait disorders. This wearable device is lightweight and can be used outdoors. This device is an automated stride assistance system that assists hip joint flexion and extension movement during walking. The torque assistance generated by the device is transmitted to the thighs through the thigh frames. In healthy young people, the heart rate during walking was significantly reduced in the with-assistance condition compared with the without-assistance condition. On the other hand, there were significant differences in length of stride, walk ratio and physical cost index in post-stroke patients with hemiparesis between the same conditions. In the slow group, in which walking speed of the first day before the start of the device was less than 60 m/min, walking speed, walk ratio and length of stride increased significantly with the 14-day protocol. Compared to the control group, the slow group had the tendency to increase the walk ratio and length of stride. The assisted walking exercise seems to improve walking parameters of the patients after stroke. The efficacy of using the device in a convalescent rehabilitation ward needs to be confirmed in a further study.

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[in Japanese]

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We have developed a Knee Joint named NAL-Knee (Natural Automatic Lock Knee) for use in trans-femoral prostheses. It has a new link (referred to as a “bouncer”) under the hydraulic cylinder of the knee joint, which can move when the load is on the heel or toe. When ascending stairs and the load is on the toe, the knee is stopped from bending at arbitrary angles; when descending and the load is on the heel, it carries out a yielding function. According to this mechanism, it becomes possible for a trans-femoral amputee to ascend and descend stairs with a reciprocal gait. This knee does not require replacement of a socket or foot and does not require batteries. With a test of oxygen uptake, we proved the merit of NAL-Knee in going up and down stairs. Although going down with NAL-Knee clearly provided excellent speed and efficiency, in going up, there is a problem of individual difference and practice. Moreover, in the flat ground gait, it turned out that the device can keep up with a range of gait speeds from walking slowly to running. This is because of the use of a large oil-hydraulics cylinder, which also lessened the oil groove resistance.

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[in Japanese]

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[in Japanese]

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The objective of this study was to investigate whether it is possible to predict the ability to walk at discharge from the physical functions at admission, in stroke patients with severe hemiplegia admitted to the sub-acute rehabilitation ward. Among stroke patients admitted to the sub-acute rehabilitation ward, 49 patients with severe hemiplegia at admission who were prescribed knee-ankle-foot orthosis were included in the study. The patients were divided into two groups according to their ability to walk at the time of discharge : ambulatory group and non-ambulatory group. Univariate analysis was conducted with respect to patient attributes neurological signs, cognitive dysfunction, and motor function at admission. In addition, for the variables showing significant differences, a discriminant analysis was conducted using walking ability at discharge as the dependent variable. Univariate analysis detected significant differences (p < 0.05) for age, neurological signs, cognitive dysfunction, trunk function, and knee extensor muscle strength on the non-hemiplegic side. Furthermore, discriminant analysis identified age, trunk function, and knee extensor muscle strength on the non-hemiplegic side as significant factors (p < 0.05). The results of the present study indicate that for stroke patients with severe hemiplegia admitted to sub-acute rehabilitation ward, the ability to walk at discharge may be predicted using the age, trunk function, and knee extensor muscle strength on the non-hemiplegic side at admission.

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The purpose of this study was to compare the surface cerebral-blood-flow changes for the use and disuse of the ankle-foot orthosis (AFO) in stroke patients with hemiplegia, using a functional near infrared spectroscopy (fNIRS) machine. Subjects were 8 outpatients of putaminal hemorrhage with hemiplegia, and a selected similar case of the bleeding part, hemiplegia, sensory disfunction and walking ability. Task 1 was walking with the AFO and Task 2 was walking without the AFO. Each task was performed on a treadmill for 30 seconds for 3 sets. In comparison with walking with the AFO, walking without the AFO significantly increased oxygenated hemoglobin in the next area ; the inside primary motor area, the outside primary motor area of the lesion side, the premotor area of the non-lesion side, the premotor area of the lesion side, and the supplementary motor area of both sides. It was confirmed that the activity of the motor area of the frontal lobe was limited by using the AFO.

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Prevention of foot dragging in the swing phase is one of the roles of ankle-foot orthosis (AFO) for the hemiplegic patient. We devised a measurement AFO that can measure the adequate dorsiflexion assist strength during the swing phase of the walk of the stroke patient according to the pathology. The measurement AFO is a plastic AFO with an ankle joint. Adequate dorsiflexion assist strength is produced by rubber bands. The adjustment of dorsiflexion assist strength is performed by choosing the position of hang nails that have been installed in the measurement AFO and the number of rubber bands attached to them. The measurement procedure was as follows : first, at the beginning confirmation of dragging of the foot in barefoot walking ; second, adjustment to adequate dorsiflexion assist strength such that dragging during walking was eliminated by the measurement AFO ; third, measurement of the dorsiflexion assist strength by the instrument ; and finally, observation of the walking exercises with the hospital-selected AFO, which is similar to the measured value. In addition, the measured value should be reflected in the AFO to own to prescribe. The indication for this procedure is the case with foot drag in the swing phase of the walk and no talipes equinus deformity.

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[in Japanese]

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