Cycling Wheelchair Provides Enjoyable Pedaling Exercises with Increased Physiological Indexes.

The cycling wheelchair (CWC) can be used as a pedaling exercise machine. However, physiological indexes in the CWC at various pedaling rates and the difference between the CWC and the existing pedaling machines such as the portable ergometer (ERG) are unclear. The aim of this study was to measure physiological indexes in the CWC at various pedaling rates and compare the CWC to the ERG, focusing on psychological stress. The present non-randomized crossover study included ten healthy men (22.3 ± 1.2 years) who performed pedaling exercise with the CWC and the ERG. Both experiments were composed of three pedaling exercise sessions (40, 60, and 80 rpm). Physiological indexes, consisting of oxygen consumption, heart rate, perceived breathlessness and leg fatigue, and salivary amylase activity (SAA), an index of psychological stress, were measured. The metabolic equivalent (METs) and the rate of change in SAA from rest to immediately after each pedaling session (ΔSAA) were calculated. In the CWC, all physiological indexes significantly increased with pedaling rates. The METs were 2.2 ± 0.3, 2.7 ± 0.4, and 3.5 ± 0.4 at 40, 60, and 80 rpm, respectively. In comparison between the CWC and the ERG, ΔSAA was lower in the CWC than in the ERG at 60 and 80 rpm. Our results indicate that the CWC pedaling can provide low or moderate intensity exercises with adjusting pedaling rates and is less stressful than the ERG. Thus, the CWC is a useful pedaling machine to promote regular and enjoyable exercises.

Preliminary tests of a prototype FES control system for cycling wheelchair rehabilitation.

The cycling wheelchair "Profhand" developed by our research group in Japan has been found to be useful in rehabilitation of motor function of lower limbs. It is also expected for rehabilitation of paraplegic subjects to propel the cycling wheelchair by lower limbs controlled by functional electrical stimulation (FES). In this paper, a prototype FES control system for the cycling wheelchair was developed using wireless surface stimulators and wireless inertial sensors and tested with healthy subjects. The stimulation pattern that stimulated the quadriceps femoris and the gluteus maximus at the same time was shown to be effective to propel the Profhand. From the analysis of steady state cycling, it was shown that the cycling speed was smaller and the variation of the speed was larger in FES cycling than those of voluntary cycling. Measured angular velocity of the crank suggested that stimulation timing have to be changed considering delay in muscle response to electrical stimulation and cycling speed in order to improve FES cycling. It was also suggested that angle of the pedal have to be adjusted by controlling ankle joint angle with FES in order to apply force appropriately.

Electrical stimulation of the abdomen preserves motor performance in the inactive elderly: a randomized controlled trial.

Abdominal muscle strength declines easily with the process of aging and/or disuse, and it is difficult to strengthen weak abdominal muscles in the inactive elderly. In the present study, we applied surface electrical stimulation (ES) to the abdomen of inactive elderly people to investigate its chronic effects. Twenty inactive elderly people (65-89 years) who spent most of the day in their bedroom participated in the study. The subjects were assigned to ES and non-ES groups in a random order. In addition to conventional physical therapy and occupational therapy, ES was applied to both sides of the flank of 10 subjects (ES group) for 8 weeks. For evaluation of the abdominal muscles, the cross-sectional area (CSA) was measured with computed tomography and the electrical muscle activity (iEMG) was measured by electromyography. Functional examinations were performed at 2, 4, and 8 weeks after the beginning of the study with the following parameters: grip strength; maximum walking speed (WS); movement time for sitting up (MSU); number of trunk flexions (NTF); flexibility of the trunk; sit-to-stand time (STS); and Barthel index (BI) score. In the ES group, the NTF and MSU were significantly improved at 4 weeks and thereafter. Furthermore, the STS and WS were also improved significantly after 8 weeks (p < 0.05). The CSA and iEMG both increased significantly (p < 0.05). However, the flexibility of the trunk and BI score did not change. In conclusion, ES to the abdomen has the potential to improve motor function in the inactive elderly.

Functional Changes in the Care-needing Elderly after Surface Electrical Stimulation to the Abdomen.

BACKGROUND: Strength of the trunk muscles is a key component of motor control, but it declines easily with the process of aging and/or disuse. OBJECTIVES: To investigate the effects of surface electrical stimulation (ES) to the abdominal muscles and the motor performance for care-needing elderly. DESIGN: Controlled trial. PARTICIPANTS: Twenty-one elderly people (60-90 years) with care-needing, who were admitted to a nursing home or hospital for daily care and their score of Barthel Index had been stable from 55.3 ± 19.4 to 55.3 ± 19.8 during 3 months before intervention. INTERVENTION: Common physical/occupational therapy was performed for all of the subjects during the study period. ES was applied to the abdomen of 15 subjects (ES group) twice a day for 8 weeks. MEASUREMENTS: Functional measurements were performed before and after beginning of the study with some parameters as follows: grip strength; movement time for sitting up (MSU); maximum walking speed (WS). RESULTS: No significant differences between two groups were noted for characteristics at baseline. In the ES group, MSU (from 21.1 ± 21.4 to 10.4 ± 8.3 sec) significantly improved (p < 0.05) after 8weeks. WS (from 17.7 ± 12.1 to 24.3 ± 15.3 m/min) were also improved (p < 0.05) after 8 weeks. LIMITATIONS: A limitation of this study was the small sample size. CONCLUSIONS: ES to the abdominal area has the potential to improve motor function in the care-needing elderly through reinforcement of the abdominal muscles.

Increase of muscle activities in hemiplegic lower extremity during driving a cycling wheelchair.

For the patients with severe hemiplegia, long-time wheelchair sitting is unavoidable, which however increases a risk of secondary impairments due to non-use of the affected leg. A cycling wheelchair (C-W/C) has a possibility to activate paretic muscle through self-locomotion with bilateral pedaling. We therefore measured driving speed of C-W/C and electromyogram (EMG) in both legs during driving in the healthy adults and severe hemiplegic patients. Ten healthy volunteers (mean age 32.8, 26-45 years) and ten non-ambulatory post-stroke patients (mean age 69.0, 55-81 years) with complete or semi-complete hemiplegia participated in this study. EMG was recorded from the key muscles for cycling during isometric movement as baseline and during driving a C-W/C straightforward. All of the patients could drive a C-W/C with mean maximum driving speed of 46.6 (31.7-61.7) m/min, which was about half of that in the healthy subjects and within practical level. Root mean square of EMG (R-EMG) as a parameter reflecting muscle activity was compared between baseline and C-W/C driving. There was no increase in most of the values of R-EMG during driving in the healthy subjects and in the intact side of the hemiplegic patients. In contrast, significant increase was found during driving in several paretic muscles, despite that EMG of the paretic leg showed almost silent at baseline. These results suggest C-W/C can induce muscle activities of the paretic leg and provide a chance of practical locomotion even for the severe hemiplegics. Daily use of a C-W/C may contribute to restore paretic leg function.

Modulation of excitability in the cerebral cortex projecting to upper extremity muscles by rotational positioning of the forearm.

The forearm rotation changes sensory inputs to the central nervous system, thereby providing orientation of the hand for grasping an object. Electrical activities of the muscles, induced by transcranial magnetic stimulation to the brain, i.e., motor evoked potentials (MEPs), are used for estimation of the excitability of motor neurons in the brain and spinal cord. It is well known that rotational positioning of the forearm influences MEPs of forearm muscles through modulation of excitability in the central nervous system. In the present study, we investigated whether such a posture-dependent change of MEPs could be found in upper arm and intrinsic hand muscles at three different rotational forearm positions: the most internal (pronation), neutral, and most external (supination) positions of rotation. MEPs were simultaneously recorded from the four muscles, biceps brachii (BB), triceps brachii (TB), abductor digiti minimi (ADM), and abductor pollicis brevis (AbPB). MEP amplitudes and latencies in BB, TB and ADM were significantly larger and shorter, respectively, in supination compared to the values in other positions. By contrast, MEP of AbPB in supination was lower in amplitude and longer in latency. Importantly, muscle lengths of TB, ADM and AbPB are constant in any rotational forearm positions, excluding the possibility of the muscle-length dependent change of spinal reflex. Therefore, these results might be attributable to the posture-dependent modulation of the motor cortex activity for the upper limb. The motor cortex probably changes the control strategy for the upper limb muscles in accordance with the sensory input from the forearm.

Virtual reality pencil and paper tests for neglect: a protocol.

Hemispatial neglect is a common disorder that can occur after a lesion in the right hemisphere. Its main characterization is the difficulty in processing visual stimuli emanating from the space contralateral to the lesion. Pencil and paper tests (such as target cancellation, line bisection, or drawing copy) are used to diagnose neglect. We propose using virtual reality technology and haptic force feedback to enhance pencil and paper tests. Our system can track the patients' eye-gaze and their hand movements. Also, the efficiency of several techniques used to decrease the neglect in different sensory spaces are investigated.

Magnetic resonance imaging of morphological and functional changes of the uterus induced by sacral surface electrical stimulation.

The purpose of this study is to examine the morphological and kinematical changes of the uterus induced by electrical stimulation applied to the skin just above the second and fourth posterior sacral foramens (sacral surface electrical stimulation [ssES]) in 26 healthy subjects. Out of them, eight subjects who had severe pain subjectively during every menstruation received ssES just in menstruation. Morphological and functional changes of the uterus were examined by using T2-weighted magnetic resonance (MR) imaging and T1-weighted MR cinematography, respectively. Cyclic electrical stimulation for 15 min with 5 sec ON and 5 sec OFF was applied just before MR scanning. A decrease in thickness of the muscular layer of the uterus was observed in every subject after ssES for 15 min and was significant as compared with the thickness before ssES. Periodic uterine movement during menstruation was observed in the subjects with severe menstrual pain in MR cine and the power spectrum analysis of the movement showed a marked decrease in peak power and frequency after ssES treatment. We conclude that ssES causes a reduction of static muscle tension of the uterus in all menstrual cycle periods and suppression of uterine peristalsis during menstruation in the subjects with severe menstrual pain. Possible neural mechanisms for these static and dynamic effects of ssES on the uterus at spinal level are discussed.

Diagnosis and rehabilitation of hemispatial neglect patients with virtual reality technology.

Victims of a stroke or an accident with damage on the parietal lobe can suffer from hemispatial neglect. This disorder is characterized by misperception of the space contralateral to the damaged area. Paper and pencil tests, such as line bisection tests, are used to diagnose hemispatial neglect. Unfortunately, they fail to quantify the degree of the neglect. Moreover, the neglect has different manifestations in each sensorial space and frame of references. In order to diagnose disorders of spatial recognition and analyze the neglected area in visual and somatic spaces, we developed a 3D-haptic virtual reality system coupled with an eye-tracking device. The haptic interface was used to interact with virtual objects. The virtual world can use the eye-gaze information to let patients overcome the neglect. We tested the system at a rehabilitation center and observed different approaches between normal subjects and hemiplegics patients. The first group was getting close to the target and then slowed down to grab it, whereas the later group proceeded by trial and error. The feature of trajectories of the hand in the 3D space could be used to determine the degree of the motion handicap. However, more specific virtual worlds are needed for efficiently extracting the feature of the patients.

Effects and indications of sacral surface therapeutic electrical stimulation in refractory urinary incontinence.

OBJECTIVE: To describe the effects and indications of sacral surface therapeutic electrical stimulation (SS-TES) for refractory urinary incontinence. DESIGN: Evaluation before and after therapy. SETTING: On clinical site and at nursing home. SUBJECTS: Seven neurogenic bladder, five unstable bladder and six nocturia cases were investigated. Twelve were outpatients and six were residents. INTERVENTIONS: Surface electrodes were placed at the posterior sacral foramens of S2 and S4. Stimulation conditions were duration 0.3 ms, frequency 20 Hz and maximum intensity. The stimulation was continued for 15 min twice daily for over one month. MAIN OUTCOME MEASURES: Therapeutic effects were evaluated on the basis of voiding charts as subjective findings and urodynamic study as objective findings before and after therapy. RESULTS: Subjective findings showed incontinence frequency significantly decreased from 2.3 +/- 1.4 times/day before therapy to 1.3 +/- 2.0 times/day after therapy (p < 0.01); 55.5% of patients were improved or greatly improved. Objective findings showed that maximum vesical capacity (MVC) significantly increased from 208.2 +/- 94.5 ml before therapy to 282.1 +/- 66.8 ml (p < 0.001). Uninhibited contraction significantly decreased from 40.4 +/- 31.4 cmH2O before therapy to 25.7 +/- 23.9 cmH2O (p < 0.01); 44% of patients were improved or greatly improved. This therapy was effective in particular for cases whose MVC was small before applying SS-TES. CONCLUSION: SS-TES was effective in some patients with refractory urinary incontinence.

Task dependent motor strategy of human triceps surae muscle.

Even though many investigators have analyzed the functional difference of the three heads of triceps surae in human, none of them succeeded to clarify the distinctive functional difference of those three muscles. The aim of this study was to investigate whether the integrated EMGs (IEMGs) of the triceps surae muscle, gastrocnemius and soleus, were task dependent. IEMGs of the medial head of the gastrocnemius (GM), lateral head of the gastrocnemius (GL), and soleus (SO) were investigated at three different knee joint angles, at four different duration of ramp contraction, with the generation of a single ongoing force, from 0 to the maximum voluntary contraction (MVC). Three-way ANOVAs for repeated measures were used to estimate differences in IEMG values in each of the GM, GL, and SO, taken at four different durations of ramp contraction (5, 10, 15 and 20 s), at three different knee joint angles (0 deg, 30 deg and 90 deg), across ankle plantar flexion levels of force (10, 20, 30, 40, 50, 60 and 70% MVC). According to three-way ANOVAs for repeated measures, IEMG of the GM muscle showed a first-order interaction between force and knee joint angle. In addition, IEMG of the GL muscle showed first-order interactions between the level of force and knee joint angle, and between the level of force and duration of ramp contraction. Furthermore, IEMG of the SO showed a main effect only on level of force. These results suggest that the each head of the triceps surae may work task dependently.

Diagnosis and rehabilitation of patients with hemispatial neglect using virtual reality technology.

Our objective is to develop and test a system for diagnosis and rehabilitation of patients with hemispatial neglect. The system consists of a 3D-haptic virtual world seen through stereo shutter-glasses. Patients interact by manipulating a haptic interface. The software adapts the virtual world accordingly to haptic interface and eye tracking feedback. Offline analysis is possible by reviewing recorded data. Observations made during experimentations with hemiplegics patients and future works with hemispatial neglect patients are discussed.

EMG-angle relationship of the hamstring muscles during maximum knee flexion.

The aim of the present study was to investigate the EMG-joint angle relationship during voluntary contraction with maximum effort and the differences in activity among three hamstring muscles during knee flexion. Ten healthy subjects performed maximum voluntary isometric and isokinetic knee flexion. The isometric tests were performed for 5 s at knee angles of 60 and 90 degrees. The isokinetic test, which consisted of knee flexion from 0 to 120 degrees in the prone position, was performed at an angular velocity of 30 degrees /s (0.523 rad/s). The knee flexion torque was measured using a KIN-COM isokinetic dynamometer. The individual EMG activity of the hamstrings, i.e. the semitendinosus, semimembranosus, long head of the biceps femoris and short head of the biceps femoris muscles, was detected using a bipolar fine wire electrode. With isometric testing, the knee flexion torque at 60 degrees knee flexion was greater than that at 90 degrees. The mean peak isokinetic torque occurred from 15 to 30 degrees knee flexion angle and then the torque decreased as the knee angle increased (p<0.01). The EMG activity of the hamstring muscles varied with the change in knee flexion angle except for the short head of the biceps femoris muscle under isometric condition. With isometric contraction, the integrated EMGs of the semitendinosus and semimembranosus muscles at a knee flexion angle of 60 degrees were significantly lower than that at 90 degrees. During maximum isokinetic contraction, the integrated EMGs of the semitendinosus, semimembranosus and short head of the biceps femoris muscles increased significantly as the knee angle increased from 0 to 105 degrees of knee flexion (p<0.05). On the other hand, the integrated EMG of the long head of the biceps femoris muscle at a knee angle of 60 degrees was significantly greater than that at 90 degrees knee flexion with isometric testing (p<0.01). During maximum isokinetic contraction, the integrated EMG was the greatest at a knee angle between 15 and 30 degrees, and then significantly decreased as the knee angle increased from 30 to 120 degrees (p<0.01). These results demonstrate that the EMG activity of hamstring muscles during maximum isometric and isokinetic knee flexion varies with change in muscle length or joint angle, and that the activity of the long head of the biceps femoris muscle differs considerably from the other three heads of hamstrings.