The purpose of this study consisting of material tests, combined material tests and subject tests was to determine which insole and built-up heel materials contributed most to shock absorption at heel strike. During the material tests, we measured the cushioning property of 5, 10, 15, and 20mm thick cork, EVA, felt, natural leather, non bound rubber, PE-lite, rubber sole (SBR), silicon rubber, soft leather, Sorbothane, and sponge rubber by dropping a shot onto each material. Five mm thick Sorbothane or silicon rubber as an insole material and 20mm thick cork, SBR, or EVA as a built-up heel material were excellent as shock absorbing materials. During the combined material tests, 20mm thick cork as a built-up heel material and 5mm thick Sorbothane or sponge rubber as an insole material, and 20mm thick EVA and 5mm thick Sorbothane or sponge rubber were found to be effective. During the subject tests the vertical force impact peaks per weight (VFIP) induced by human drop were measured on a Kistler force platform. We tested 6 subjects who wore an Oxford shoe with each combination of an insole material: 5mm thick Sorbothane, silicon rubber or sponge rubber and a built-up heel material: 20mm thick EVA, cork or natural leather. VFIPs of the combinations of natural leather and insole materials were significantly smaller than those of the combinations of EVA or cork and insole materials. As the results of the subject tests were not consistent with those of the combined material tests, an additional human drop test at which a subject wore an Oxford shoe with a fixed ankle joint was performed. The additional test revealed that VFIPs of EVA was smaller than those of natural leather. We, therefore, concluded that an ankle joint compensatory movement induced a shock absorbing function in the case of a natural leather heel at heel strike and that shock absorbing materials should be prescribed for shoes if a patient has an ankle joint disorder and limited range of motion. We propose that the best standard prescription of shock absorbing materials is 5mm sponge rubber as an insole material and 20mm EVA as a built-up heel material. It is important to consider the cushioning properties of insole and built-up heel materials for patients with ankle joint disorders at heel strike.

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The purpose of this investigation was to identify the muscle function of patients with cerebral palsy (CP) by electromyogram (EMG) and muscle sound (MS). Voluntary contractions of the elbow flexor muscle during their maximum effort (MVC) and at the several levels of contraction from 10% to 50% of MVC were performed on 5 CP patients and 8 normal volunteers. The MVC normalized with the cross-sectional area of muscle (MVCa) in CP group was significantly lower than that in normal group. The ratio of root mean square values between MS and EMG was determined as an indicator of transformation from the electrical activity to the mechanical output in the contractile system. The MS/EMG ratio in CP group was approximately 50% less than that in normal group. The results suggest that the lower MVCa in CP group was due to deconditioning of mechanical function of the muscle fibers, not due to that of electrical activities of neuromuscular system.

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Sixteen patients with Guillain-Barré syndrome were investigated retrospectively in order to determine the prognostic effect of clinical features on the rehabilitation outcomes. They were divided into two groups: eight early-recovered patients and eight delayed-recovered patients. The early-recovered patients, “early” group, got at almost complete recovery within 6 months from the onset of illness and the others, “delayed” group, did not. The age of onset was significantly older in the “delayed” group with average age of 47.0 than that in the “early” group with average age of 27.3. The muscle weakness during progressive phase of the illness and respiratory insufficiency were also significantly more serious in the “delayed” group than those in the “early” group. Despite of some persisting disabilities, three of eight delayed-recovered patients became to be ambulant around 6 months from the onset of illness and another four patients regained their walking abilities with the cane and orthosis beyond one year from the onset. While all the early-recovered patients returned to their premorbid social states, only two patients among the “delayed” group regained a paid job. More effective approach to eliminate the handicaps should be designed for the delayed-recovered patients.

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In 16 patients with SMON (group S) and 35 elderly healthy controls (group A), stabilograms were recorded for 15 seconds with the eyes open. Group S was divided into two subgroups: group S1, comprised of patients who did not need support in walking, and group S2, comprised of patients who required support in walking.
Stability was statistically worse in group S2 than in groups A and S1, although there was no difference in stability between group Si and group A. Similarly, central motor conduction time (CMCT) was prolonged in group S2, compared with groups A and S1. In group S, there was a good correlation between stability and CMCT; the worse a patient's stability was, the slower CMCT was.
In SMON, patients with disability in walking have worse stability than those without disability in walking. This finding suggests that impaired stability parallels central motor system impairment.

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