The purpose of this study was to clarify the relationship between asymmetrical sciatic support, seat posture angle, and buttocks shear forces during usage of reclining wheelchairs. Participants included 11 healthy adult men (20.8 ± 0.6 years old). There were no left-right differences in sciatic pressures (no difference) for control conditions. Cushions with different left-right thicknesses were applied to create sciatic pressure asymmetries (difference) in the experimental condition. A shear force was then applied to the buttocks under each condition. Measurements were performed on the right and left girth during the return to an upright position (RUP) from a starting position in which the back-support was reclined. The initial upright position (IUP) was 10 degrees vertical from the original position. The shear force applied to the buttocks was measured and the rate of change was calculated based on the initial value determined during the IUP. As a result, the left side gluteal displacement force change rate was significantly higher under difference (experimental) conditions. These findings suggest that when a reclining wheelchair is used, asymmetrical sciatic support exacerbates the relationship between higher seat pressures, adding more significant shear forces to the buttocks.

Chitosan is a chemical extract and a natural antibacterial and antifungal agent found in crab and shrimp shells, and its activity against Staphylococcus aureus and Trichophyton species has been confirmed. Bacteria and fungi mostly grow between the prosthesis socket and stump of organisms, thereby causing an unpleasant odor and infectious eschar. This study aimed to verify whether the antibacterial and antifungal effects of chitosan were maintained when it was added to the thermosetting resin while preparing fiber-reinforced plastics (FRP), and it was observed that the FRP made of the resin containing chitosan powder did not reveal antibacterial or antifungal effects. As a result, there was no difference in antibacterial properties against Staphylococcus aureus, fungi, or general bacteria in the chitosan-containing resin FRP. However, it was revealed that FRP, which is generally used in the field of prosthetics and orthotics, has an antibacterial effect against Staphylococcus aureus and Trichophyton mentagrophytes.

In recent years, the changes in demographic structure resulting from the falling birthrate are becoming social problems. In midst of this, the elderly are expected to play active roles as workers. However, there are many cases of people becoming bedridden due to falls. The risk of falling down increases especially in the cold and snowy climate of winter, which makes fall prevention an urgent priority in Japan’s aging population. Therefore, we started developing smart boots which aim to prevent falls on winter roads. In this study, we examined the automatic anti-slipping system. We built a shoe which incorporated the automatic anti-slipping system, and conducted a gait experiment. As a result, it was possible to maintain an anti-slip state. It was also possible to control the anti-slip state with the swing phase. In conclusion, it was suggested that this system can be used during walking.

The purpose of this study was to clarify the kinetic and kinematic effects of walking exercise using the walking assist device ACSIVE on the gait in a hemiplegic stroke patient. The walking exercise was performed using ACSIVE on the paralyzed side at a comfortable speed for 1,000 steps. After the walking exercise, the hip maximum flexion angle was decreased and the hip maximum extension angle was increased, the maximum hip extension moment during the loading response was decreased and the maximum hip flexion moment was increased, the maximum knee flex angle during the loading response was decreased, the cadence increased, and the stride on the paralyzed side was decreased, compared to before the walking exercise. It was suggested that assist in hip flexion and resistance to hip extension on the paralyzed side in walking exercise at a comfortable speed using ACSIVE had a motor learning effect different from the wearing effect in the walking of a hemiplegic stroke patient.

Shoulder prosthesis is reported to be difficult to accept and continue to use due to the heavy weight and reduced operating efficiency of the prostheses. Refusal rates are reported to be higher than those for other major forms of amputation. The proportion of persons with high level amputation in Japan is small and very little reported. In this study, training and evaluation of a body-powered prosthesis and hybrid myoelectric prosthesis were conducted for an adult man who had suffered unilateral forequarter amputation by trauma. The Southampton Hand Assessment Procedure (SHAP) score was higher with the body-powered prosthesis than with the hybrid myoelectric prosthesis ; however, the effectiveness of the hybrid myoelectric prosthesis was revealed in his workplace.