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To advance our knowledge on the motor system during cyclic gait observation, we aimed to explore the effects of gaze fixation on corticospinal excitability evaluated by single-pulse transcranial magnetic stimulation (TMS). Fourteen healthy adult volunteers watched a video of a demonstrator walking on a treadmill under three different conditions: (1) observing the right lower limb, (2) observing the right ankle joint, and (3) observing the right lower limb on a video focused on the area below the knee. In each condition, motor-evoked potentials elicited by TMS in the tibialis anterior (TA) muscle were measured synchronously with the demonstrator’s initial contact and toe-off points. Directing visual attention to the ankle joint and focusing on its movements caused corticospinal facilitation in the TA muscle compared with watching the video without any visual fixation. In addition, phase-dependent differences in corticospinal excitability between the initial contact and toe-off points were only detected when the visibility range was restricted to below the knee. Our findings indicated that motor resonance during cyclic gait observation is modulated by visual attention and motion visibility in different activation manners.

The activities of the suprahyoid muscles have been reported to be induced by tongue muscle contraction. The purpose of this research was to investigate whether tongue-strengthening exercises using a device cause hypertrophy of the geniohyoid muscle in healthy adults. Seven healthy young adults (3 men and 4 women, 21.0 ± 1.3 years old) received 8-week tongue muscle training with the JMS Tongue Pressure Measuring Device. The participants were instructed to press the anterior tongue against the hard palate 30 times in each session, three sessions a day, and 3 days a week. The exercise intensity was set to 60% of maximum tongue pressure in the first week, and to 80% of maximum tongue pressure for the remaining period. The training effect was evaluated by measuring (1) maximum tongue pressure value with the JMS Tongue Pressure Measuring Device, and (2) the area at rest, shortening amount, and contraction ratio of the geniohyoid muscle using ultrasonic imaging. After the 8-week training program, the maximum tongue pressure increased significantly from 44.9 to 61.6 kPa. The area of the geniohyoid muscle at rest also increased significantly from 2.3 to 2.6 cm2 after the program. There were no significant differences in the shortening amounts and the contraction ratios of the geniohyoid muscle between the values before and after the program. The tongue-strengthening exercise was useful to increase the muscle power of the geniohyoid, as well as the tongue muscles, in healthy young adults.

Objective The aim of the present study was to investigate whether anterior tongue muscle strengthening exercises can affect the strength of posterior tongue muscles. Design Eleven healthy subjects (20.6 ± 1.2 years) were included. The subjects exercised by pushing the anterior tongue to the palate 30 times, three times a day, 3 days a week for 8 weeks. The exercise intensity was set at 60% of maximum tongue pressure (MTP) in the first week and 80% of MTP for the remainder of training. After the completion of training, MTP measurements were continued every month for another 3 months to evaluate whether training effects were sustained. Results MTP was significantly increased after 8 weeks of training compared with before training. No significant differences were seen between MTP immediately after completion of training and MTP 1–3 months after completion of training. However, MTP was significantly higher 1–3 months after completion of training than before training. Conclusions The present study showed significant increases in both anterior and posterior MTPs by anterior tongue muscle strengthening exercises. In the future, a database on tongue muscle strengthening exercises in elderly persons, patients with dysphagia, etc. will need to be generated, with the aim of preventing frailty.

Objectives: We performed a survey of medical records to reveal the cognitive deficits behind dangerous driving in patients with higher brain dysfunction. Methods: Thirty-four patients with higher brain dysfunction were included in this study. Patients’ basic characteristics, neuropsychological test results, scores on two types of driving aptitude tests, and accident/near miss data from a driving simulator were extracted from medical records. We conducted χ2 tests for independence between comprehensive driving aptitude scores and “traffic accidents” / “being prohibited from driving as defined by the number of traffic accidents and near misses.” Backward logistic regression analysis was carried out to assess correlations of “traffic accidents” and “being prohibited from driving as defined by the number of traffic accidents and near misses” with neuropsychological test scores. Results: No significant correlation was observed between the comprehensive driving aptitude score and “traffic accidents” / “being prohibited from driving as defined by the number of traffic accidents and near misses.” The score on the Raven’s Colored Progressive Matrices test was the only factor identified as a significant predictor of “being prohibited from driving as defined by the number of traffic accidents and near misses.” Conclusions: The results of this study suggest that it is important to focus on the decline in problem-solving ability as a predictor of “being prohibited from driving as defined by the number of traffic accidents and near misses.”

Objective: The aim of this study was to investigate the effect of repetitive peripheral magnetic stimulation (rPMS) on muscle atrophy prevention in the rectus femoris muscle (RF) of the paretic limb in acute stroke patients. Methods: Twelve acute stroke patients with a National Institute of Health Stroke Scale score >5 and a motor score of the paretic lower limb >2 at admission were divided into an intervention group (rPMS: mean age, 75±6.4 years) and a conventional care group (non-rPMS: mean age, 62±11.8 years). Baseline measurements were performed within 4 days of stroke onset. In the rPMS group, treatment was applied to the paretic thigh only for 2 weeks, 5 days a week, in addition to conventional care. The cross-sectional area (CSA) of the RF was assessed in both limbs using ultrasound at baseline and 2 weeks later. Data on patient characteristics were collected from the clinical records to assess correlations with the CSA rate of change. Results: Patients in the rPMS group were significantly older. Although the CSA of the RF did not change significantly on either side in the rPMS group, there was a significant decrease in the CSA on the paretic side in the non-rPMS group. However, no significant difference was observed in the CSA rate of change in the rPMS and non-rPMS groups. The CSA rate of change on the paretic side correlated negatively with age in the rPMS group. Conclusions: Our results suggest that rPMS prevents muscle atrophy more effectively in patients in their 60s than in patients more than 70 years old.

Transcranial magnetic stimulation (TMS) has been widely utilized to noninvasively explore the motor system during the observation of human movement. However, few studies have characterized motor cortex activity during periodic gait observation. Thus, this study examined the effects of an observer's visual experience and/or intention to imitate on corticospinal excitability during the observation of another's gait. Twenty-six healthy volunteers were included in this study and allocated to two different groups. Participants in the visual experience group had formal experience with gait observation (physical therapist training), while those in the control group did not. Motor-evoked potentials induced by TMS in the tibialis anterior and soleus muscles were measured as surrogates of corticospinal excitability. Participants were seated and, while resting, they observed a demonstrator's gait or observed it with the intention to subsequently reproduce it. Compared with the resting state, cyclic gait observation led to significant corticospinal facilitation in the tibialis anterior and soleus muscles. However, this pattern of corticospinal facilitation in the measured muscles was not coupled to the pattern of crural muscle activity during actual gait and was independent of the step cycle. This motor cortex facilitation effect during gait observation was enhanced by the observer's visual experience in a manner that was not step cycle-dependent, while the observer's intent to imitate did not affect corticospinal excitatory input to either muscle. In addition, visual experience did not modulate corticospinal excitability in gait-related crural muscles. Our findings indicate that motor cortex activity during gait observation is not in line with the timing of muscle activity during gait execution and is modulated by an individual's gait observation experience. These results suggest that visual experience acquired from repetitive gait observation may facilitate the motor system's control on bipedal walking, but may not promote the learning of muscle activity patterns.

Objective Dynamic videofluoroscopic swallow study (VFSS) is used to investigate swallowing movements. However, it requires prolonged radiation exposure and mainly provides qualitative information. Herein, we present a multi-dimensional method for analyzing swallowing based on a pulsed, low-dose fluoroscopy technique that uses serial-shot images and evaluates the size, position, and temporal profile of the bolus to obtain a more comprehensive and realistic analysis of swallowing movements. Methods Fifteen healthy adults drank two liquids: 20 mL of pure water followed by 20 mL of contrast medium mixture in a fluoroscopic study. Data were recorded in serial-shot images (7.5 frames/second, 1024 × 1024-pixel resolution, DICOM format). The images from the water and contrast swallows were inverted, synchronized, and subtracted to visualize the bolus in each frame. The pathway of the bolus was divided into 15 parts traversing the oropharynx, hypopharynx, and upper esophagus, and the total gray value was measured in each section. The results were presented as contour graphs. Results The contour graphs allowed for information on the size, anatomical location, and temporal location of the bolus during swallowing to be displayed simultaneously. Two distinct swallowing patterns were observed in the subjects. The bolus showed two peaks—one in the hypopharynx and one in the upper esophagus—in all subjects. However, in nine of the 15 subjects, the two peaks were in different frames, whereas in six of the subjects, the two peaks were in the same frame. Conclusion We developed a new method for quantitatively evaluating swallowing. The technique allows for multidimensional assessment of the size, position, and temporal profile of the movement of the bolus across the pharynx. This method evaluates the swallowing movements using sharp, high-resolution images obtained by serial-shot, pulsed fluoroscopy with low radiation exposure. Additional studies are required to further clarify the variability of swallowing patterns and their clinical relevance in the evaluation of swallowing movements in healthy subjects and in patients with swallowing disorders.

Metani H, Tsubahara A, Hiraoka T, Seki S, Hasegawa T. Risk factors for patients who develop pneumonia either before or after hip fracture surgery. Jpn J Compr Rehabil Sci 2015; 6: 43-49. Objective: The objectives of this study were to examine the risk factors for patients who develop pneumonia either before or after hip fracture surgery and to investigate the utility of dysphagia rehabilitation and oral care. Methods: The medical histories of 145 patients who were hospitalized for a new hip fracture and underwent surgical treatment were retrospectively investigated, and the rate of and risk factors for pneumonia were evaluated. Results: The rate of pneumonia with hip fracture was 14.5%. Psychiatric disorders, history of stroke, time between admission and surgery, blood hemoglobin concentration, serum total protein level, and serum albumin level were risk factors associated with pneumonia. In particular, the serum albumin level and psychiatric disorders were independent risk factors. Conclusion: The majority of pneumonias that develop either after admission or after hip fracture surgery are considered to be aspiration pneumonias, and their frequency was greater than expected. Since patients with malnutrition or psychiatric disorders are more susceptible to pneumonia, ascertaining the patient’s activities of daily living prior to injury and conducting thorough oral care are considered essential for preventing aspiration pneumonia.

Sugawara H, Ishikawa M, Takayama M, Okamoto T, Sonoda S, Miyai I, Fujitani J, Tsubahara A. Effect of tube feeding method on establishment of oral intake in stroke patients with dysphagia: comparison of intermittent tube feeding and nasogastric tube feeding. Jpn J Compr Rehabil Sci 2015; 6: 1-5. Purpose: To compare the effects of two tube feeding management methods; nasogastric tube feeding and intermittent tube feeding, implemented during the process of rehabilitation for dysphagia due to cerebrovascular disorders on the outcome of oral intake. Methods: Dysphagic patients who were admitted to convalescent rehabilitation wards because of cerebrovascular disorders were divided into two groups: 398 patients who underwent nasogastric tube feeding (NG group) and 114 patients who underwent intermittent tube feeding (ITF group). The two groups were compared with respect to outcome of dysphagia rehabilitation. Results: The proportion of patients who were able to meet nutrition needs by oral intake of three meals alone at discharge was significantly higher in the ITF group than in the NG group (71% versus 53%, p = 0.0007). The proportion of patients showing improvement in food intake level scale (FILS) during hospitalization was also significantly higher in the ITF group (p = 0.007). The mean duration from admission to start of direct training was significantly shorter in the ITF group than in the NG group (9.6 ± 13.9 days versus 19.1 ± 25.8 days, p = 0.001). The mean duration from admission to start of oral food intake was also significantly shorter in the ITF group than in the NG group (20.1 ± 26.4 days versus 27.3 ± 31.8 days, p = 0.049). Conclusion: The results in this study suggest that tube feeding management using ITF achieves better outcome of dysphagia rehabilitation compared to using NG.

To explore the effects of qualitative or quantitative changes in walking on motor cortical excitability, a transcranial magnetic stimulation procedure was used to examine the alterations of motor-evoked potential (MEP) amplitude following walking. Eight healthy participants completed a series of two walking tasks on a treadmill at 2 km/h. The ratio of the left stance duration to the right stance duration was 1 : 2 in the asymmetrical walking task and 1 : 1 in the symmetrical walking task. In each task, walking for 10 min followed by MEP measurement for ∼4 min was repeated three times. MEP measurements were also performed before a walking task as a baseline and continued every 10 min for a further 30 min after the completion of the walking task. During slight voluntary contraction of the left tibialis anterior muscle, MEP measurements were conducted four times. Although a significant MEP depression was found after the asymmetrical walking task with increasing amount of walking, no significant decrease in MEP below baseline was observed after the symmetrical walking task throughout all measurement sessions. This MEP depression was the prominent response to the asymmetrical walking task compared with the symmetrical walking task. These findings indicate that the intentional control of walking pattern has both temporal and task-specific influences on excitability changes in the cerebral cortex, and suggest that motor cortical excitability may be altered by controlling the amount of central commands to the legs even during gait exercise.

Arai N, Metani H, Abe R, Shimizu S, Seki S, Hiraoka T, Hanayama K, Tsubahara A. Utility of full-body thermotherapy for an elderly patient with multiple organ complications requiring lower-leg amputation. Jpn J Compr Rehabil Sci 2014; 5: 61-65. This report describes the case of an elderly amputee (lower leg) with obstructive arteriosclerosis, diabetes, angina (post CABG), and intractable ulcers on the non-amputated leg. The patient received full-body thermotherapy using heat packs and thermal sheeting and was subsequently able to walk. Despite drug therapy to improve peripheral circulation in addition to meticulous foot care, ulcers on the foot of the nonamputated side worsened. After full-body thermotherapy, however, skin perfusion pressure improved, and the ulcers gradually healed. The patient was discharged home, at which time the combined use of Lofstrand crutches, a prosthesis, and a footplate for pressure relief enabled outdoor walking for short distances. Patients with skin lesions who undergo amputation as a consequence of peripheral circulation disorders often have difficulty walking with a prosthetic limb. Moreover, the full-body thermotherapy provided similar effectiveness to the Waon dry sauna therapy, which is available only at a limited number of institutions. This thermotherapy is a promising supplemental therapy for elderly amputees with circulatory disorders, and could easily be provided by many institutions.

Minami K, Nagatomi F, Watanabe S, Tsubahara A. Effect of fingertip touch on postural sway during static standing in patients with femoral neck or trochanteric fracture. Jpn J Compr Rehabil Sci 2014; 5:50-55. Objective: Patients with femoral neck or trochanteric fracture (hip fracture) are considered to be at high risk for falling. We investigated whether a light fingertip touch on a stable surface (LT) with a force insufficient to provide mechanical support of the body could stabilize static standing. We also investigated whether the effect differed between LT and heavy fingertip touch (HT) or between ipsilateral and contralateral fingertip touch (relative to the fracture). Methods: Eleven patients with hip fracture who were hospitalized in a kaifukuki (convalescence) rehabilitation ward participated in the study. The sway of the center of pressure (COP) during static standing was measured and compared under five fingertip touch conditions.

Shimizu S, Metani H, Hiraoka T, Seki S, Hanayama K, Tsubahara A. Electrode position and hyoid movement in surface electrical stimulation of the suprahyoid muscle group. Jpn J Compr Rehabil Sci 2014; 5: 97-​ 101. Objective: To determine the relationship between electrode position and hyoid movement for effective surface electrical stimulation in the treatment of dysphagia. Methods: Surface electrode pairs targeted on the suprahyoid muscle group were placed in mesial, distal, or pervasive placement patterns on the skin anterior to the suprahyoid muscle group of five healthy subjects, and the vertical and horizontal movements of the hyoid induced by electrical stimulation in the three pattern groups were measured and compared. Results: The mesial electrode-pair pattern induced significant anterior movement of the hyoid. The distal pattern showed a tendency to induce upward hyoid movement. The distance of hyoid movement induced by the electrical stimulation was about half of that found for actual water swallowing. No significant difference in electrical stimulus intensity was found among the electrode patterns. Conclusion: Surface electrical stimulation with mesial electrode-pair placement anterior to the hyoid presumably induces contraction of the digastric muscle anterior belly and the geniohyoid muscle, and was found to pull the hyoid forward. This information and further elucidation of the relationship between surface electrode position and hyoid movement is expected to increase the range of clinical applications.

Objective The purpose of this study was to investigate the most suitable site and method to effectively generate isometric hip flexion torque (torque value) using transcutaneous electrical or magnetic stimulation. Design Eleven healthy volunteers underwent torque value and pain degree measurements during magnetic stimulation of the iliopsoas using three coil placements. After that, the peak torque values generated under three conditions of electrical stimulation of the sartorius, the tensor fasciae latae, and the rectus femoris or that generated by magnetic stimulation of the iliopsoas were recorded at maximum tolerance intensity. Results No significant differences in torque values were observed among the three coil placements. Magnetic stimulation of the point below the inguinal ligament caused significantly more pain than the other points. Magnetic stimulation of the iliopsoas generated significantly higher torque values than did the electrical stimulation of the two hip flexor muscles together. Conclusions The hip joint was one of the most suitable regions for application of magnetic stimulation as an alternative method to electrical stimulation.

When eating solids, stage II transport (St2Tr) propels triturated food into the pharynx for bolus formation and storage before swallowing. Although the existence of St2Tr is acknowledged, the reason for its existence remains unclear. Understanding it may facilitate development of food appropriate for individuals with dysphagia. The purpose of this study was to explore how measures of duration of eating and swallowing affect the number of St2Tr cycles.Videofluorography was performed on 13 healthy subjects eating 6-g squares of banana, tofu, and cookies. Measurements included the number of St2Tr cycles, duration of processing (from food entering the mouth to onset of swallowing), pre-upper esophageal sphincter (UES) transit duration (from onset of swallowing to onset of UES transit), UES transit duration (leading edge to trailing edge passing the UES), and total sequence duration (from onset of swallowing to terminal swallow). Principal component (PC) analysis was used to identify factors affecting the number of St2Tr cycles. Analysis of covariance was performed using the 1st PC as an independent variable for predicting the number of St2Tr cycles.All four duration measures were significantly positively correlated with the number of St2Tr cycles. Analysis revealed two orthogonal PCs with variable loading. The 1st PC was a function of the timing variables. The 2nd PC was a function of the number of swallows.The number of St2Tr cycles was associated with measures of food transit duration and was greater with harder foods before processing and more viscous foods just before swallowing.

The purpose of this study was to confirm that the arytenoid regions dynamically adduct and extend upward toward the epiglottis during laryngeal elevation. While 14 healthy volunteers aged 19–32 years old swallowed 5 ml of white soft yogurt in one gulp without chewing, the movement of the arytenoid regions was observed for videoendoscopic evaluation of swallowing (VE). Each moving image was stored simultaneously on videotape. A cross-sectional area surrounded by the epiglottis and the bilateral arytenoid regions (S) and the length of a straight line passing through the anterior borders of the left and right arytenoid regions (L) were measured. The relative area of the entrance in the laryngeal vestibule was calculated as [S/L 2] before the swallowing reflex (resting condition), just before laryngeal closure, and just after laryngeal closure. [S/L 2] was smaller just before epiglottal descent than at the resting condition, and became smallest just after the epiglottis started to ascend. The mean area narrowed to 37.9% of the resting area just after laryngeal closure and in the most extreme case to 8.7% of the resting area. It was demonstrated that the arytenoid regions adducted and extended up toward the epiglottis during laryngeal elevation. The technique used to measure the cross-sectional area of the entrance in the laryngeal vestibule employing VE was an effective analytical procedure.

We used desk-based tasks to evaluate and clarify the effects of colour lightness differences (Liebmann effect) in patients with left unilateral spatial neglect (USN) following stroke. Participants were 30 adults with USN (16 men and 14 women; mean age = 72.3 years, SD = 8.9 years). They took the ‘Letter Cancellation Test’ of the Japanese version of the Behavioral Inattention Test using two types of paper: black letters with a yellow background (‘black on yellow’) and red letters with a green background (‘red on green’). They also took the Line Bisection Test and their laterality index (LI) was also determined. Paired t-tests were computed comparing the LI by colour displays. LI was higher for ‘black on yellow’ than for ‘red on green’ in patients with mild left USN. However, LI for ‘red on green’ was higher in patients with severe left USN. Colour lightness differences are likely on the left side in patients with relatively mild left USN, but not in those with severe left USN.

The rare hereditary disorder Fanconi anemia (FA) can be caused by mutations in components of the FA core complex (FancA/B/C/E/F/G/L/M), a key regulator FancD2, the breast cancer susceptibility protein BRCA2/FancD1, or the newly identified FancJ/BRIP1 helicase. By performing yeast two-hybrid (Y2H) screens using N-terminal chicken (ch) FancD2 as a bait, we have identified chFancL, the likely ubiquitin E3 ligase subunit of the FA core complex. We also found that ectopically expressed FancD2 and FancL co-immunoprecipitated in 293T cells, and this interaction was dependent on the PHD domain of FancL. FANCL-disrupted chicken DT40 cells displayed defects in both FancD2 monoubiquitination and focus formation. Importantly, cell lines lacking the FANCL or FANCD2 genes, or carrying a "knock-in" mutation of the FancD2 monoubiquitination site (where the Lys 563 residue is changed to Arg), displayed quantitatively identical defects in the repair of I-SceI-induced chromosomal breaks by homologous recombination (HR). These data establish the role of FANCL and FancD2 monoubiquitination in HR repair.

Articulation is driven by various combinations of movements of the lip, tongue, soft palate, pharynx and larynx, where the tongue plays an especially important role. In patients with cerebrovascular disorder, lingual motor function is often affected, causing dysarthria. We aimed to evaluate the effect of visual biofeedback of posterior tongue movement on articulation rehabilitation in dysarthria patients with cerebrovascular disorder. Fifteen dysarthria patients (10 men and 5 women; mean age, 70.7 ± 10.3 years) agreed to participate in this study. A device for measuring the movement of the posterior part of the tongue was used for the visual biofeedback. Subjects were instructed to produce repetitive articulation of [ka] as fast and steadily as possible between a lungful with/without visual biofeedback. For both the unaffected and affected sides, the range of ascending and descending movement of the posterior tongue with visual biofeedback was significantly larger than that without visual biofeedback. The coefficient of variation for these movements with visual biofeedback was significantly smaller than that without visual biofeedback. With visual biofeedback, the range of ascent exhibited a significant and strong correlation with that of descent for both the unaffected and affected sides. The results of this study revealed that the use of visual biofeedback leads to prompt and preferable change in the movement of the posterior part of the tongue. From the standpoint of pursuing necessary rehabilitation for patients with attention and memory disorders, visualization of tongue movement would be of marked clinical benefit.

Patients with Parkinson’s disease develop gait disturbances. Although the use of walkers is very effective for maintaining locomotive ability, patients who have symptoms such as frozen gait (FG) and festinating gait may fall even with a walker equipped with a brake as they cannot use the brake well in an emergency and fail to follow the accelerating walker. None of the studies on walking aids to date have addressed real-time detection of FG or the use of this information for the control of the walking aid, monitoring of the state of improvement in the ambulatory function, or evaluation of the effect of the use of a walker. In this study, we evaluated whether the state called FG, a characteristic symptom of Parkinson’s disease, can be detected by the use of a sensor-controlled walker with heel-to-toe pressure sensors. The following two measurements were carried out in one male healthy and a one male patient with stage 3 Parkinson’s disease by the Hoehn-Yahr scale showing mild muscle rigidity, hypokinesia, and FG. In the healthy subject, the heel-to-toe pressure showed smooth heel-to-toe shifts during the standing phase. In the patient with Parkinson’s disease, the heel-to-toe response time was about 2.4 times longer than in the healthy subject at the beginning of walking, and FG could be recorded as the difficulty in lifting the foot by the toes. Also, when FG was observed during walking, the pressure waves recorded by the same sensors showed two peaks occurring at a short interval, indicating double landings.

脳卒中患者の口腔内環境は劣悪なことが多い.唾液は口腔内環境に関与する因子だが,その定量は脳卒中患者でほとんど行われていない.そこでガーゼを噛むことで唾液量が測定可能なSaxon testに関し,脳卒中患者29名で再現性,年齢・片麻痺の重症度・嚥下障害の有無との関連を検討した.検査は同日に2回(2回目は15分後),後日(5日以内)に1回施行した.両者ともIntraclass correlationは0.94,0.81と高値であり,脳卒中患者においても信頼性は高かった.脳卒中患者の唾液分泌傾向は平均3.6gと,文献上における日本の健常者平均5gより少なく,シェーグレン症候群患者の1.4gより多かった.唾液分泌量低下が脳卒中患者の口腔状態を劣化させている可能性があり,その対策を検討する必要性が示唆された.その際,Saxon testは唾液分泌量の評価方法として利用可能であると考えられた.

Background The incidence of low back pain (LBP) is high in patients with hip osteoarthritis (OA). Evidence from previous studies suggests that lumbar alignments and hip range of motion (ROM) are important etiological factors for LBP. However, no studies have investigated which factors that have the greatest influence on LBP. Objective This investigation aimed to collectively examine factors related to LBP in patients with hip OA, including lumbar lordosis angle (LLA), leg length discrepancy (LLD), and hip ROM. Methods Thirty-five patients participated in this study. LBP was treated as a dependent variable, whereas hip ROMs were treated as independent variables. Patients' age and body mass index (BMI) were recorded as confounding factors, as were LLA and LLD. A logistic regression model was performed to determine the most accurate set of variables to predict LBP. Results BMI and ROM of hip flexion on the affected side were identified as significant variables. Conclusions Our results suggest that BMI and ROM of hip flexion on the affected side are related to LBP in patients with hip OA and need to be assessed.

Our previous single-pulse transcranial magnetic stimulation (TMS) study revealed that excitability in the motor cortex can be altered by conscious control of walking relative to less conscious normal walking. However, substantial elements and underlying mechanisms for inducing walking-related cortical plasticity are still unknown. Hence, in this study we aimed to examine the characteristics of electromyographic (EMG) recordings obtained during different walking conditions, namely, symmetrical walking (SW), asymmetrical walking 1 (AW1), and asymmetrical walking 2 (AW2), with left to right stance duration ratios of 1:1, 1:2, and 2:1, respectively. Furthermore, we investigated the influence of three types of walking control on subsequent changes in the intracortical neural circuits. Prior to each type of 7-min walking task, EMG analyses of the left tibialis anterior (TA) and soleus (SOL) muscles during walking were performed following approximately 3 min of preparative walking. Paired-pulse TMS was used to measure short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF) in the left TA and SOL at baseline, immediately after the 7-min walking task, and 30 min post-task. EMG activity in the TA was significantly increased during AW1 and AW2 compared to during SW, whereas a significant difference in EMG activity of the SOL was observed only between AW1 and AW2. As for intracortical excitability, there was a significant alteration in SICI in the TA between SW and AW1, but not between SW and AW2. For the same amount of walking exercise, we found that the different methods used to control walking patterns induced different excitability changes in SICI. Our research shows that activation patterns associated with controlled leg muscles can alter post-exercise excitability in intracortical circuits. Therefore, how leg muscles are activated in a clinical setting could influence the outcome of walking in patients with stroke.

The aim of this study was to investigate oropharyngeal pressure flow dynamics during dry swallowing in ten healthy subjects. Tongue pressure (TP) was measured using a sensor sheet system with five measuring points on the hard palate, and pharyngeal pressure (PP) was measured using a manometric catheter with four measuring points. The order and correlations of sequential events, such as onset, peak, and offset times of pressure production, at each pressure measuring point were analyzed on the synchronized waveforms. Onset of TP was earlier than that of PP. The peak of TP did not show significant differences with the onset of PP, and it was earlier than that of PP. There was no significant difference between the offset of TP and PP. The onset of PP was temporally time-locked to the peak of TP, and there was an especially strong correlation between the onset of PP and TP at the posterior-median part on the hard palate. The offset of PP was temporally time-locked to that of TP. These results could be interpreted as providing an explanation for the generation of oropharyngeal pressure flow to ensure efficient bolus transport and safe swallowing.

The effects of hypoxia and ischemia on the firing rate of fibrillation potentials in denervated rat muscle were examined. We recorded electromyograms from the denervated left extensor digitorum longus muscle. Hypoxia was induced by low-oxygen ventilation. Ischemia was established by ligating the abdominal aorta and inferior vena cava, with or without extracorporeal hindlimb perfusion. The fibrillation potential firing rate correlated with the PaO2 (P < 0.0001) and temperature (P = 0.0001). Fibrillation potentials disappeared after the initiation of ischemia and reappeared after restitution of blood flow; they disappeared during ischemia with extracorporeal perfusion. The attenuation curves for the firing rate of fibrillation potentials during ischemia were well-described by exponential curves, but there was no significant difference in the attenuation constants for circulatory arrest and perfusion with a physiologic salt solution. We conclude that the fibrillation potential firing rate is proportional to oxygen supply, presumably because of the rate of aerobic metabolism.

末梢神経を高頻度反復刺激した場合の複合筋活動電位(compound muscle action potentials: CMAPs)の振幅漸増現象に関する生理学的機序を明らかにするために,健常者10名を対象として,正中神経,尺骨神経を反復刺激した.得られたCMAPsについて振幅,面積および活動持続時間を計測し,さらにフィルター設定の違いによる変化について検討した.正中神経および尺骨神経刺激では20Hzと30Hzの刺激頻度で振幅が漸増したが,活動持続時間は漸減し,面積はごくわずかに減少していた.また,高周波フィルターを極度に低く設定した場合以外には常時振幅漸増現象が認められた.高頻度反復刺激にるCMAPsの振幅漸増現象の発現機序としては,神経終末での細胞内へのCa2+の取り込みからAch放出までの時間またはMFAPsの筋線維内伝搬時間の短縮,あるいは容積伝導の変化に基づくものと推測される.

To the Editor, We are pleased to report on the development and progress of the trans-disciplinary field of Deglutology in Japan as the Japanese Society of Dysphagia Rehabilitation (JSDR) commemorates its 20th year of establishment. The JSDR includes a broad range of disciplines in order to integrate diverse knowledge and expertise and pave the way for the emerging field of Deglutition. The percentage of individuals aged over 65 years reached 25.0 % of the Japanese population in 2013 [1]. With this rapid increase in the elderly, a substantially greater demand for dysphagia rehabilitation comes up. As the progression of dysphagia diminishes both the function of swallowing and the enjoyment of eating, the objective of dysphagia rehabilitation should therefore address both the recovery of swallowing function and the restoration of pleasure while eating. Dysphagia rehabilitation is performed for a wide range of disease stages, from acute medical care to terminal support. Although a team approach is essential for effective rehabilitation, treatment can be challenging because support strategies vary considerably over time and require numerous approaches and caregivers. We normally divide the team approach in dysphagia rehabilitation into three categories according to the relationships among participating disciplines as follows: (1) the multi-disciplinary approach, where disciplines treat patients independently and have little communication with each other, (2) the inter-disciplinary approach, where related disciplines exchange information at team conferences to reach a consensus on treatment, thus promoting inter-disciplinary cooperation, and (3) the trans-disciplinary approach, where participating disciplines complement the scope of others to more efficiently integrate a team approach. The trans-disciplinary approach is particularly suitable for dysphagia rehabilitation because the size and composition of a support team may change significantly over time; complementing the scopes of associated disciplines without establishing a rigid inter-disciplinary border enables seamless care over a wider range of individuals, symptom stages, and circumstances. The JSDR was founded in 1995 under the concept of a trans-disciplinary approach for dysphagia rehabilitation. As the society now celebrates 20 years of progress and innovation, its membership has grown to more than 11,000 medical professionals (11,653 as of August 30, 2014) and involves numerous disciplines (Fig. 1) in line with the original JSDR trans-disciplinary tenets. Recently, the 20th annual conference of the JSDR held in Tokyo in September 2014 featured an international symposium that included 12 E. Saitoh Department of Rehabilitation Medicine I, School of Medicine, Fujita Health University, Toyoake, Aichi, Japan e-mail: esaitoh@fujita-hu.ac.jp