The purpose of this study is to investigate the relationship between joint angle and EMG activity concerning the human knee joint and hamstring muscles. Ten healthy males participated in this study. They performed maximum voluntary isokinetic knee flexion in the flexion angle range of 0° to 120° in a prone position on a table. The EMG activities of the semitendinosus, semimembranosus, long and short heads of the biceps femoris muscles were detected by bipolar fine wire electrode, and were integrated at knee flexion range intervals of 15° from 0° to 120°. After three months, the same examination was performed with the same subjects to confirm the reliability of this study. Results showed the mean peak isokinetic torque was attained from a 15° to 45° knee flexion angle. The EMG activities of the hamstring muscles varied with changes in the knee flexion angle. The integrated EMG of the semitendinosus, semimembranosus and short head of the biceps femoris muscles in-creased gradually as the knee flexion angle was increased from 0° to 105°. The peak integrated EMG of these three muscles was attained between 90° and 105° knee flexion in both trials. On the other hand, the peak integrated EMG of the long head of the biceps femoris muscle was largest at a knee angle ranging from 15° to 30°. Peak integrated EMG decreased when the knee flexion angle increased in both trials. These results show that the electromyographic activity of agonist muscles during maximum voluntary movement varied with the change of muscle length or joint angle. Therefore, it was considered that the relationship between joint torque and joint angle is influenced not only by the sarcomere length and the moment arm but also muscle activities of agonist muscles, even if the movement is performed with maximum effort.

Taping is widely used in sports medicine to prevent injury, protect affected sites post injury and relieve pain. However, it is not clear whether taping affects the perception of noxious stimulation because in previous studies, it was difficult to selectively activate Aδ fibers. A recently developed, useful, new tool named intra-epidermal electrical stimulation (IES) can preferentially activate Aδ fibers. We aimed to clarify the effect of taping on pain-related somatosensory evoked potentials (pSEPs) using IES. We recorded pSEPs following IES of the right medial forearm in twelve healthy volunteers. pSEPs were recorded from 9 electrodes on the scalp under control, elastic-taping and white-taping conditions. Under the control condition, subjects relaxed on a comfortable reclining seat without taping, whereas under the taping conditions, they were subjected to taping along the forearm with tension (elastic-taping) and without tension (white-taping). Subjects were asked to assign a visual analog scale (VAS) score after each session. The peak amplitudes of N2-P2 were significantly lower under the elastic-taping and white-taping conditions than those under the control condition. VAS was significantly lower elastic-taping condition than those under the control and white-taping conditions. Moreover, there was a significant positive correlation between the amplitude of N2-P2 and VAS. We revealed that taping along the forearm decreased pSEPs and subjective pain perception under the white-taping and elastic-taping conditions. The underlying mechanism of pain relief was the distraction effect in both taping conditions. In addition, elastic-taping with tension changes afferent inputs mainly from the skin, and this might more effectively decrease the subjective pain perception than that achieved under the white-taping condition.

Taping is widely used by sports trainers to prevent injury and to protect affected sites post-injury. However, it is not clear whether taping affect the perception of somatosensory stimulation. We sought to clarify the effect of taping on somatosensory stimulation using somatosensory evoked potentials (SEPs). We recorded SEPs following transcutaneous electrical stimulation of the right medial forearm in ten healthy volunteers. SEPs were recorded from 9 electrodes on the scalp under control, elastic-taping and white-taping conditions. Subjects relaxed on a comfortable reclining seat without taping in the control condition, while they were subjected to taping along the muscle of forearm with tension (elastic-taping) and without tension (white-taping) in the taping conditions. Results showed that the peak amplitude of N140 did not differ significantly among the three conditions but the peak amplitude of P250 was significantly lower in the elastic-taping condition than control and white-taping conditions. Elastic-taping with tension along the muscles changes various afferent inputs from muscle spindle or skin, and this may affect the perception of somatosensory stimulation.

A questionnaire-based survey of board-certified rehabilitation physicians was conducted to identify issues in multidisciplinary interprofessional collaboration and to assess the abilities of board-certified rehabilitation physicians needed to develop assistive devices for individuals requiring long-term care. From the 366 responses, it was revealed that they consider “the ability to gain an insight into what patients need from assistive devices” and the “ability to communicate” as essential abilities needed to develop assistive devices. The respondents considered the ability to communicate and convey information important to overcome differences in thought-process between disciplines；the sharing of information, objectives, and knowledge as a requirement for teamwork；and collaboration, including with the patients, to be important. This approach to device development fits well with “design thinking” and “biodesign.” Unfortunately, more than 70％ of the respondents were unfamiliar with these concepts. Therefore, it is necessary to provide opportunities for rehabilitation physicians to learn innovative biodesign approaches.

A questionnaire-based survey of board-certified rehabilitation physicians was conducted to identify issues in multidisciplinary interprofessional collaboration and to assess the abilities of board-certified rehabilitation physicians needed to develop assistive devices for individuals requiring long-term care. From the 366 responses, it was revealed that they consider “the ability to gain an insight into what patients need from assistive devices” and the “ability to communicate” as essential abilities needed to develop assistive devices. The respondents considered the ability to communicate and convey information important to overcome differences in thought-process between disciplines；the sharing of information, objectives, and knowledge as a requirement for teamwork；and collaboration, including with the patients, to be important. This approach to device development fits well with “design thinking” and “biodesign.” Unfortunately, more than 70％ of the respondents were unfamiliar with these concepts. Therefore, it is necessary to provide opportunities for rehabilitation physicians to learn innovative biodesign approaches.