Role of the medial agranular cortex in unilateral spatial neglect.

Unilateral spatial neglect (USN) results from impaired attentional networks and can affect various sensory modalities, such as visual and somatosensory. The rodent medial agranular cortex (AGm), located in the medial part of the forebrain from rostral to caudal direction, is considered a region associated with spatial attention. The AGm selectively receives multisensory input with the rostral AGm receiving somatosensory input and caudal part receiving visual input. Our previous study showed slower recovery from neglect with anterior AGm lesion using the somatosensory neglect assessment. Conversely, the functional differences in spatial attention across the entire AGm locations (anterior, intermediate, and posterior parts) are unknown. Here, we investigated the relationship between the severity of neglect and various locations across the entire AGm in a mouse stroke model using a newly developed program-based analysis method that does not require human intervention. Among various positions of the lesions, the recovery from USN during recovery periods (postoperative day; POD 10-18) tended to be slower in cases with more rostral lesions in the AGm (r = - 0.302; p = 0.028). Moreover, the total number of arm entries and maximum moving speed did not significantly differ between before and after AGm infarction. According to these results, the anterior lesions may slowly recover from USN-like behavior, and there may be a weak association between the AGm infarct site and recovery rate. In addition, all unilateral focal infarctions in the AGm induced USN-like behavior without motor deficits.

Developing a Novel Prosthetic Hand with Wireless Wearable Sensor Technology Based on User Perspectives: A Pilot Study.

Myoelectric hands are beneficial tools in the daily activities of people with upper-limb deficiencies. Because traditional myoelectric hands rely on detecting muscle activity in residual limbs, they are not suitable for individuals with short stumps or paralyzed limbs. Therefore, we developed a novel electric prosthetic hand that functions without myoelectricity, utilizing wearable wireless sensor technology for control. As a preliminary evaluation, our prototype hand with wireless button sensors was compared with a conventional myoelectric hand (Ottobock). Ten healthy therapists were enrolled in this study. The hands were fixed to their forearms, myoelectric hand muscle activity sensors were attached to the wrist extensor and flexor muscles, and wireless button sensors for the prostheses were attached to each user's trunk. Clinical evaluations were performed using the Simple Test for Evaluating Hand Function and the Action Research Arm Test. The fatigue degree was evaluated using the modified Borg scale before and after the tests. While no statistically significant differences were observed between the two hands across the tests, the change in the Borg scale was notably smaller for our prosthetic hand (p = 0.045). Compared with the Ottobock hand, the proposed hand prosthesis has potential for widespread applications in people with upper-limb deficiencies.

Effect of Trunk Solution® on hemodynamics in the supplementary motor area during walking.

[Purpose] Humans keep their trunks vertical while walking. This defining characteristic is known as upright bipedalism. Research on the neural control of locomotion indicates that not only subcortical structures, but also the cerebral cortex, especially the supplementary motor area (SMA), is involved in locomotion. A previous study suggested that SMA may contribute to truncal upright posture-control during walking. Trunk Solution® (TS) is a trunk orthosis designed to support the trunk in decreasing the low back load. We hypothesized that the trunk orthosis might reduce the burden of truncal control on the SMA. The objective of this study was, therefore, to determine the effect of trunk orthosis on the SMA during walking. [Participants and Methods] Thirteen healthy participants were enrolled in the study. We measured the hemodynamics of the SMA during walking with functional near-infrared spectroscopy (fNIRS). The participants performed two gait tasks on a treadmill: (A) independent gait (usual gait) and (B) supported gait while wearing the TS. [Results] During (A) independent gait, the hemodynamics of the SMA exhibited no significant changes. During (B) gait with truncal support, the SMA hemodynamics decreased significantly. [Conclusion] TS may reduce the burden of truncal control on the SMA during walking.

Peak vertical ground force of hand-knee crawling in human adults.

[Purpose] Fall risk is immanent in humans because they are bipedal. Bipedalism has transited from quadrupedalism in both evolutional and developmental contexts. Past studies have measured the peak vertical ground force of forelimbs and hindlimbs in quadrupedalism; and revealed that load dominancy shifted from forelimbs to hindlimbs during evolution. The dominance of hindlimb peak vertical ground force allows forelimb freedom and is considered important for locomotor evolution toward bipedalism. With this consideration, we hypothesize that hindlimb peak vertical ground force is dominant in human adults when they designedly crawl in a quadrupedal manner. [Participants and Methods] Six healthy human adults crawled on their hands and knees over a pressure platform. We calculated the peak vertical ground force of their hands and knees by integrating the pressure of the contact area of each limb. [Results] The mean knee peak vertical ground force at 0.694 (per body weight) was significantly higher than that of the hand at 0.372 (per body weight). The mean hand/knee peak vertical ground force ratio was 0.536; therefore, it was -0.624 on the natural logarithmic scale. [Conclusions] Our findings on human adults are compatible with existing considerations on locomotor evolution toward bipedalism. Our findings contribute to the comprehensive understanding of human locomotion.

Effect of experimentally induced plantar pain on trunk posture during gait.

[Purpose] Plantar pain is associated with the prevalence of low back pain. Therefore, it is reasonable to assume that some kind of physical change should be occurring in the trunk due to plantar pain. However, the physical effect of plantar pain on the trunk remains unknown. We evaluated the effect of plantar pain on trunk posture during gait. [Participants and Methods] Ten healthy volunteers participated in the present study. Participants walked under two conditions: without pain and with pain. In the with pain condition, we set pain-inducing devices to the right foot to induce plantar pain during stance phase. By using 3D motion analysis system, the angles of the head, thorax, and pelvis segments, as well as the neck, trunk, bilateral hip, bilateral knee, and bilateral ankle joints, were measured. We analyzed the angle data throughout the gait cycle by using one-dimensional statistical parametric mapping. [Results] The anterior trunk tilt was observed in the right stance phase. [Conclusion] The anterior trunk tilt observed in the with pain condition may be a burden on the trunk. Our results presented one of the possible reasons for increased prevalence of low back pain in the plantar pain patients.

Multiple patterns of infant rolling in limb coordination and ground contact pressure.

Infants acquire the ability to roll over from the supine to the prone position, which requires body coordination of multiple degrees of freedom under dynamic interactions with the ground. Although previous studies on infant rolling observed kinematic characteristics, little is known about the kinetic characteristics of body segments in contact with the surface. We measured the ground contact pressure under the arms, legs, head, and proximal body segments using a pressure mat and their displacements using a three-dimensional motion capture system. The data obtained from 17 infants aged 9-10 months indicated that most of them showed 2-4 of 6 highly observed movement patterns, including 1 axial rolling, 2 spinal flexion, and 3 shoulder girdle leading patterns. The arms and legs had small contributions to the ground contact pressure in the axial rolling and spinal flexion patterns. The ipsilateral leg in relation to the rolling direction was involved in supporting the body weight in only 1 shoulder girdle leading pattern. The contralateral leg showed large peak pressure to push on the floor before rolling in 3 shoulder girdle leading patterns. The results indicate that infants can produce multiple rolling-over patterns with different strategies to coordinate their body segments and interact with the floor. The results of the analysis of the movement patterns further suggest that few patterns correspond to those reported in adults. This implies that infants generate unique motor patterns by taking into account their own biomechanical constraints.

Direct evidence of EEG coherence in alleviating phantom limb pain by virtual referred sensation: Case report.

Virtual reality (VR) systems have been integrated into rehabilitation techniques for phantom limb pain (PLP). In this case report, we used electroencephalography (EEG) to analyze corticocortical coherence between the bilateral sensorimotor cortices during vibrotactile stimulation in conjunction with VR rehabilitation in two PLP patients. As a result, we observed PLP alleviation and increased alpha wave coherence during VR rehabilitation when stimulation was delivered to the cheek and shoulder (referred sensation areas) of the affected side. Vibrotactile stimulation with VR rehabilitation may enhance the awareness and movement of the phantom hand.

Influence of a Foot Insole for a Down Syndrome Patient with a Flat Foot: A Case Study.

Background and Objectives: Patients with Down syndrome have many orthopedic problems including flat foot. Insertion of an insole for a flat foot provides support to the medial longitudinal arch; thus, insole therapy is often used to treat a flat foot. However, the influence of an insole insertion on the knee joint kinematics for a patient with Down syndrome is unknown. This study aimed to elucidate the influence of an insole for a flat foot on the knee kinematics during gait for a patient with Down syndrome. Materials and Methods: The subject was a 22-year-old male with Down syndrome who had a flat foot. The knee joint angle during the gait was measured using a 3D motion capture system that consisted of eight infrared cameras. Results: The gait analysis demonstrated a reduction in the knee flexion angle during double knee action. The knee valgus and tibial internal rotation angles also decreased during the loading response phase while wearing shoes that contained the insole. Conclusions: As the angle of the knee joint decreased during the gait, it was considered that the stability of the knee joint improved by inserting the insole. In particular, there was a large difference in the tibial internal rotation angle when the insole was inserted. It is thus hypothesized that the insole contributes to the rotational stability of the knee joint. This study suggests that knee stability may improve and that gait becomes more stable when a Down syndrome patient with a flat foot wears an insole.

Use of malleoli as an indicator for flatfoot in patients with Down syndrome: development of a simple and non-invasive evaluation method through medial longitudinal arch.

[Purpose] Flatfoot often presents in patients with Down syndrome, and it can be diagnosed using a simple radiograph. Consequently, due to radiograph limitations, alternative non-invasive testing must be determined. Conventionally, arch height ratio can be used for evaluation of the medial longitudinal arch, where the foot is evaluated by detecting the navicular bone on the foot surface. However, detection of the navicular tuberosity is difficult and even though the detection is relatively straightforward for patients without intellectual disability, measuring navicular bone is more difficult in patients with intellectual disability, such as those who have Down syndrome and are uncooperative with a tester. Therefore, we evaluated arch height ratio using the malleoli instead of the navicular bone to determine whether malleoli testing was appropriate for patients with Down syndrome that have an intellectual disability. [Participants and Methods] We conducted a retrospective study of 16 pairs of feet in 16 patients with Down syndrome, diagnosed with flatfoot. The height to the centre of the talo-navicular joint and that of the malleoli from the sole were measured on radiographs using weight-bearing conditions. [Results] The age range was 5.2 to 25.3 years. There was a correlation between the height of the navicular bone and that of the medial and lateral malleoli. [Conclusion] We conclude that the medial and lateral malleoli can substitute navicular bone as a landmark diagnosis test for flatfoot. Considering the close physical distance between the medial malleolus and navicular bone, and the association between the tibia and medial longitudinal arch, the medial malleolus may provide a better landmark in patients with Down syndrome with it being potentially less invasive for uncooperative patients.

Robotic rehabilitation of the paralyzed upper limb for a stroke patient using the single-joint hybrid assistive limb: a case study assessed by accelerometer on the wrist.

[Purpose] Recent studies have reported the effectiveness of robotic rehabilitation of paralyzed upper limbs in stroke patients. For example, the Single-Joint Hybrid Assistive Limb has been shown to improve upper limb impairments. However, limited data are available on the effectiveness of robotic rehabilitation of the upper limb with regards to daily living. In this case study, an accelerometer was adopted to examine whether rehabilitation using the Single-Joint Hybrid Assistive Limb improved upper limb activity during daily living in a stroke patient. [Participant and Methods] The participant was a 69-year-old male diagnosed with stroke and left hemiparesis. The Single-Joint Hybrid Assistive Limb was applied to the participant's elbow on the paralyzed side. The participant wore an accelerometer on each wrist to measure the activities of the upper limbs. Clinical tests of the paralyzed upper limb were also performed. [Results] The activity of the paralytic limb was significantly higher after Single-Joint Hybrid Assistive Limb intervention than before the intervention. On the other hand, none of the results of the clinical tests changed beyond a clinically important difference. [Conclusion] The Single-Joint Hybrid Assistive Limb could be useful for promoting active use of a paralyzed upper limb in daily living. In addition, an accelerometer could be especially useful for evaluating the effects of robotic rehabilitation.

Adjusting Assistance Commensurates with Patient Effort During Robot-Assisted Upper Limb Training for a Patient with Spasticity After Cervical Spinal Cord Injury: A Case Report.

Limited evidence is available on optimal patient effort and degree of assistance to achieve preferable changes during robot-assisted training (RAT) for spinal cord injury (SCI) patients with spasticity. To investigate the relationship between patient effort and robotic assistance, we performed training using an electromyography-based robotic assistance device (HAL-SJ) in an SCI patient at multiple settings adjusted to patient effort. In this exploratory study, we report immediate change in muscle contraction patterns, patient effort, and spasticity in a 64-year-old man, diagnosed with cervical SCI and with American Spinal Injury Association Impairment Scale C level and C4 neurological level, who underwent RAT using HAL-SJ from post-injury day 403. Three patient effort conditions (comfortable, somewhat hard, and no-effort) by adjusting HAL-SJ's assists were set for each training session. Degree of effort during flexion and extension exercise was assessed by visual analog scale, muscle contraction pattern by electromyography, modified Ashworth scale, and maximum elbow extension and flexion torques, immediately before and after each training session, without HAL-SJ. The amount of effort during training with the HAL-SJ at each session was evaluated. The degree of effort during training can be set to three effort conditions as we intended by adjusting HAL-SJ. In sessions other than the no-effort setting, spasticity improved, and the level of effort was reduced immediately after training. Spasticity did not decrease in the training session using HAL-SJ with the no-effort setting, but co-contraction further increased during extension after training. Extension torque was unchanged in all sessions, and flexion torque decreased in all sessions. When performing upper-limb training with HAL-SJ in this SCI patient, the level of assistance with some effort may reduce spasticity and too strong assistance may increase co-contraction. Sometimes, a patient's effort may be seemingly unmeasurable; hence, the degree of patient effort should be further measured.

Gait Training Using the Honda Walking Assistive Device® in a Patient Who Underwent Total Hip Arthroplasty: A Single-Subject Study.

BACKGROUND AND OBJECTIVES: The Honda Walking Assistive device® (HWA) is a light and easywearable robot device for gait training, which assists patients' hip flexion and extension movementsto guide hip joint movements during gait. However, the safety and feasibility of robot-assisted gaittraining after total hip arthroplasty (THA) remains unclear. Thus, we aimed to evaluate the safetyand feasibility of this gait training intervention using HWA in a patient who underwent THA. MATERIALS AND METHODS: The patient was a 76-year-old woman with right hip osteoarthritis. Gaittraining using HWA was implemented for 20 sessions in total, five times per week from 1 week to5 weeks after THA. Self-selected walking speed (SWS), step length (SL), cadence, timed up and go(TUG), range of motion (ROM) of hip extension, and hip abduction and extension torque weremeasured preoperatively, and at 1 (pre-HWA), 2, 3, 4, 5 (post-HWA), and 10 weeks (follow-up) afterTHA. The gait patterns at SWS without HWA were measured by using three-dimensional (3D) gaitanalysis and an integrated electromyogram (iEMG). RESULTS: The patient completed 20 gait trainingsessions with no adverse event. Hip abduction torque at the operative side, hip extension torque,SWS, SL, and cadence were higher at post-HWA than at pre-HWA. In particular, SWS, TUG, andhip torque were remarkably increased 3 weeks after THA and improved to almost the same levelsat follow-up. Maximum hip extension angle and hip ROM during gait were higher at post-HWAthan at pre-HWA. Maximum and minimum anterior pelvic tilt angles were lower at post-HWA thanat pre-HWA. The iEMG of the gluteus maximus and gluteus medius in the stance phase were lowerat post-HWA than preoperatively and at pre-HWA. CONCLUSIONS: In this case, the gait training usingHWA was safe and feasible, and could be effective for the early improvement of gait ability, hipfunction, and gait pattern after THA.

The prevalence of the flat foot condition and insole prescription in people with Down's syndrome: a retrospective population-based study.

[Purpose] The general approach for flat foot (FF) treatment in people with Down's syndrome (DS) is the use of insoles. However, the appropriate timing of the first insole prescription remains unclear. An aim of this present research was to investigate the status of prevalence of FF and orthosis prescription in the DS population. [Subjects and Methods] Two hundred fifteen subjects with DS who were seen at our hospital were retrospectively investigated. Investigated parameters were: prevalence of FF and other foot diseases, ratio and timing of orthopaedic consultation, ratio and timing of orthoses prescription, and mean age at the time of orthosis prescription. [Results] The prevalence of FF was 27.0% (58 subjects), and 50 subjects (23.3%) consulted an orthopaedic surgeon. An orthosis was prescribed for 54 subjects; 88.9% of these orthoses were insoles. Foot and leg orthoses other than insoles were prescribed significantly more frequently for females than males. The mean ages at the time of the first prescription of all types of orthoses and an insole were 7.3 years and 6.4 years, respectively. [Conclusion] The prevalence of FF was low, and the age at which subjects with DS were prescribed an orthosis was relatively high at our institution compared to previous reports. Since physical therapists see patients who could potentially have FF, those with suspected FF should then be referred to an orthopaedic doctor, which would enable the earlier orthosis prescription.

Relationship between the use of lower extremity orthoses and the developmental quotient of The Kyoto Scale of Psychological Development in children with Down syndrome.

[Purpose] The Kyoto Scale of Psychological Development is an evaluation scale developed in the field of psychology. The initial aim of this study was to determine whether the quotient of the Postural-Motor area in the scale was correlated with the use of orthosis in patients with Down syndrome. The second aim was to examine a correlation among Postural-Motor, Cognitive-Adaptive, and Language-Social areas in the participants. [Participants and Methods] Patients with Down syndrome who had received a developmental examination, the Kyoto Scale of Psychological Development, were retrospectively investigated. The sample included 78 participants. Data on the participants' calendar ages ranged from 4.1 to 6.0 years, and the mean age was 4.9 at the examination. The investigated parameters were the number of participants who used an orthosis or insole and the mean developmental quotient for the Postural-Motor, Cognitive-Adaptive, and Language-Social areas. [Results] Twenty participants who completed the exam used an orthosis, and 18 of these had an insole as a first orthosis. The mean Postural-Motor quotient was significantly lower in participants who used an orthosis than in those who did not (52.3 ± 14.7). [Conclusion] The mean quotient of the Postural-Motor area was significantly lower in patients with Down syndrome who were prescribed some kind of orthosis than in those who were not. There was a significant correlation among the quotients of the three areas. The use of orthosis was expected to positively influence the Cognitive-Adaptive and Language-Social areas through the future in people with Down syndrome who have some difficulty with posture and movement.

Comparison of sleep status among three Japanese national wheelchair basketball teams.

[Purpose] Sufficient sleep is required for maximal performance and good mood. Japan has three national wheelchair basketball teams: Top male, Top female, and Under-23 (U23) male teams. Using these team members as model, this study investigated the difference of sleep status of wheelchair basketball players by age and gender. [Subjects and Methods] There were 44 participants: 14 in the Top male team (29.5 ± 5.2 years), 18 in the Top female team (30.6 ± 9.2 years), and 12 in the U23 team (19.1 ± 2.0 years). Sleep status was assessed with the Pittsburgh Sleep Quality Index (PSQI); higher scores indicate poor sleep quality. [Results] PSQI scores in the Top male and female teams were higher than in the U23 team. The Top teams showed shorter sleep duration and worse sleep efficacy than the U23 team. Time spent in bed and sleep duration in the female team were shorter than in the Top male and U23 teams. More male players reported "feel too hot" as the reason for sleep disturbance than female players. [Conclusion] Players in the Top Japanese national wheelchair basketball teams had poorer sleep status than U23 players. Among female players, the reason for insomnia was less sleep duration. For males, the reason for insomnia was "feel too hot."

Long-term sustained effect of gait training using a hybrid assistive limb on gait stability via prevention of knee collapse in a patient with cerebral palsy: a case report.

[Purpose] The hybrid assistive limb was developed to improve the kinematics and muscle activity in patients with neurological and orthopedic conditions. The purpose of the present study was to examine the long-term sustained effect of gait training using a hybrid assistive limb on gait stability, kinematics, and muscle activity by preventing knee collapse in a patient with cerebral palsy. [Participant and Methods] A 17 year-old male with cerebral palsy performed gait training with a hybrid assistive limb 12 times in 4 weeks. After completion of 12 sessions of hybrid assistive limb training, monthly follow-up was conducted for 8 months. The improvement was assessed on the basis of joint angle and muscle activity during gait. [Results] The degree of knee collapse observed at baseline was improved at 8-month follow-up. Regarding muscle activity, electromyography revealed increased activation of the vastus lateralis at 8-month follow-up. Moreover, the hip and knee angles were expanded during gait. In particular, the knee extension angle at heel contact was increased at 8 months after follow-up. [Conclusion] Gait training with a hybrid assistive limb provided improvement of gait stability such as kinematics and muscle activity in a patient with cerebral palsy. The improved gait stability through prevention of knee collapse achieved with hybrid assistive limb training sustained for 8 months.

Inclination of standing posture due to the presentation of tilted view through an immersive head-mounted display.

[Purpose] The purpose of the present study is to clarify whether tilted scenery presented through an immersive head-mounted display (HMD) causes the inclination of standing posture. [Subjects and Methods] Eleven healthy young adult males who provided informed consent participated in the experiment. An immersive HMD and a stereo camera were employed to develop a visual inclination system. The subjects maintained a standing posture twice for 5s each while wearing the visual inclination system. They performed this task under two conditions: normal view and 20° leftward tilted view. A three-dimensional motion analysis system was used to measure the subjects' postures, and two force plates were used to measure the vertical component of the floor reaction force of each leg. [Results] In the 20° leftward tilted view, the head and trunk angles in the frontal plane were similarly inclined toward the left, and the vertical component of the floor reaction force increased in the left leg, whereas it decreased in the right leg. [Conclusion] When the view in the immersive HMD was tilted, the participants' trunk side bent toward the same side as that of the view. This visual inclination system seems to be a simple intervention for changing standing posture.

Hemodynamic Response of the Supplementary Motor Area during Locomotor Tasks with Upright versus Horizontal Postures in Humans.

To understand cortical mechanisms related to truncal posture control during human locomotion, we investigated hemodynamic responses in the supplementary motor area (SMA) with quadrupedal and bipedal gaits using functional near-infrared spectroscopy in 10 healthy adults. The subjects performed three locomotor tasks where the degree of postural instability varied biomechanically, namely, hand-knee quadrupedal crawling (HKQuad task), upright quadrupedalism using bilateral Lofstrand crutches (UpQuad task), and typical upright bipedalism (UpBi task), on a treadmill. We measured the concentration of oxygenated hemoglobin (oxy-Hb) during the tasks. The oxy-Hb significantly decreased in the SMA during the HKQuad task, whereas it increased during the UpQuad task. No significant responses were observed during the UpBi task. Based on the degree of oxy-Hb responses, we ranked these locomotor tasks as UpQuad > UpBi > HKQuad. The order of the different tasks did not correspond with postural instability of the tasks. However, qualitative inspection of oxy-Hb time courses showed that oxy-Hb waveform patterns differed between upright posture tasks (peak-plateau-trough pattern for the UpQuad and UpBi tasks) and horizontal posture task (downhill pattern for the HKQuad task). Thus, the SMA may contribute to the control of truncal posture accompanying locomotor movements in humans.

Estimation of center of pressure information by smartphone sensors for postural control training.

Postural control training based on physical information is a common rehabilitation training method for patients with movement disorder. This research aims to verify the feasibility of using one smartphone embedded sensors to estimate CoP (Center of Pressure) displacement to take postural control training. We tested the reliability of smartphone sensor by motion capture system based on the following two CoP calculation models: (1) one-link inverted pendulum model; (2) two-link inverted pendulum model. We compared the estimation results with real CoP values measured by force plate. Sway training experiment was conducted under two tasks conditions: feet apart and feet together. The results show that data obtained from smartphone sensors is capable of representing human body CoM (Center of Mass) information. These two models can roughly estimate CoP displacement; and the results suggested that the two-link model performed better than one-link model. The estimation error between smartphone and real value is 0.70 - 2.01 cm in feet apart task and 1.03 - 1.12 cm in feet together task with two-link model.Clinical Relevance- This study verified the performance of smartphone in estimating CoP displacement for postural control training.

Effect of Sway Frequency on the Joint Angle and Center of Pressure in Voluntary Sway.

Voluntary sway is the periodic movement of one's body back and forth. The study aimed to clarify the effects of sway frequency on center of pressure and joint angle during voluntary sway. We measured 10 unrestricted voluntary sway conditions with different frequencies and natural pace conditions. The frequencies ranged from 0.1 to 1 Hz in 0.1-Hz increments. The joint angles and centers of pressure during voluntary sway were compared between the conditions. The joint angle amplitude of the trunk and knee were greater in the slow frequency condition than in the fast frequency condition. The trunk and knee joint angles during voluntary sway were considered to change according to the sway frequency.