To clarify electrically-induced muscle fatigue, the relationship between muscle tension and the myoelectrical signals as well as the spatial extent of the glycogendepleted muscle fibers were investigated in the rat hindlimb muscles. Fifty-four male Wistar rats (12 to 16-week-old) were included. Under general anesthesia, tibialis anterior (TA) and soleus (SOL) muscles (20 limbs respectively) were exposed and their distal tendons were attached to the force transducer to measure the isometric tension. A small electrode array consisting of stimulating needles and recording bars was placed over the muscle belly, and tetanic electrical stimulation was applied for 30s at a frequency of either 20Hz or 40Hz. Peak-to-peak amplitude and peak latency of the M-wave, and the muscle fiber conduction velocity (MFCV) were analyzed. The MFCVs were corrected to the temperature of 26°C. Histochemical analysis was done for 6 TA muscles after the electrical stimulation. Serial cross-sections of the muscles were stained by the periodic-acid Schiff (PAS) reaction to show the glycogen-depleted muscle fibers near the stimulating electrodes. During tetanic electrical stimulation, progressive amplitude depression and latency increase of the M-waves as well as slowing of the MFCVs were found which were always preceded by decline of the isometric tension. The speed of these changes differed significantly between TA and SOL muscles and between 20 and 40Hz of stimulation frequencies. After the fatiguing 60 s-stimulation, the glycogen depletion occurred in a wedge-shaped area with clear margins, which was thought to correspond to the electricallyactivated muscle fibers. Monitoring the M-waves, especially their amplitudes, seems valuable for detecting muscle fatigue before actual tension drops. The results of PAS staining suggest that increasing stimulus intensity to take countermeasures against the tension drop may be of value for automatic control of functional electrical stimulation for the paralyzed muscle in the field of rehabilitation medicine.

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There have been few reports in patients with stroke about the motor skills of unaffected lower limbs of themselves excluding the functional influence of their trunks. The purpose of this study was to determine whether significant differences in the motor skills of lower limbs existed between normal persons and patients with stroke. Subjects were divided into two groups. The first group, consisting of 42 individuals (52.1±15.2yrs; 22 patients with stroke, 5 patients with neurological motor dysfunction and 15 healthy controls), underwent analysis of measurement reproducibility with a Computerized Leg Exercise Assisting Machine (C-LEAM). The second group included 20 patients with hemiparesis (53.7±10.3yrs) and 30 normal controls (52.3±8.1yrs). This group was studied with respect to motor skills of the unaffected lower limb in stroke cases. Patients with spatial hemineglect and bilateral hemisphere lesions were excluded. The motor skills of lower limbs were evaluated with which tested the accuracy of trajectory tracking. C-LEAM was designed to provide a real-time two-dimensional positioning of the foot fixed on a freely movable square. The position of the foot (foot marker) and the target track of the moving foot were shown on the display. Patients were instructed to track a figure “8” pattern from the seated position with the unaffected foot. Tracking of the mirror image of the foot marker, displayed at the mirror-image positioning, was also performed. Trajectory Errors {TE_g: geometrical TE: (cm²/cycle), TE_idt: TE integrated distance/time (cm·sec/cycle)} in this tracking task of the unaffected lower limbs of patients with stroke were compared with those of the ipsilateral lower limbs of the normal controls. Regarding the unaffected lower limb, correlation coefficients between the initial trial of Trajectory Errors (TE_g and TE_idt) in this tracking task and the second trial were r=0.95 in TE_g (p<0.0001) and r=0.70 in TE_idt (p<0.0001) in the normal figure pattern and r=0.80 in TE_g (p<0.0001) and r=0.98 in TE_idt (p<0.0001), respectively. TE_g and TE_idt of patients with stroke with Rt hemiplegia were significantly larger than those of the normal controls. Those of patient with Lt hemiplegia were also larger than those of the controls. TE_g and TE_idt values in mirrored tracking task among the hemiplegic subjects were significantly larger than those of the normal controls. Correlation coefficient between TE and mirrored TE was r=0.67 (p<0.0001). The unaffected lower limbs of patients with hemiparesis have typically been considered to be nearly normal. Present results using C-LEAM demonstrated the impaired motor skills of the unaffected lower limb of patients with hemiparesis. Detailed evaluation of unaffected lower limb function and rehabilitative training are necessary.

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We reported a case of parkinsonism caused by acute carbon monoxide poisoning. A 62-year-old man was admitted to our hospital with severe parkinsonism. On admission, prognosis of his symptoms was unknown. From the episode of carbon monoxide inhalation and his brain MRI findings, he was diagnosed as interval form of carbon monoxide poisoning. Rehabilitation and medication had been done with a prediction of improvement because duration of consciousness disturbance after the poisoning was not so long. And after 6 month, his symptoms were almost improved. This suggested that it was helpful to get a detailed information of acute stage when we made a plan of rehabilitation in a patient with carbon monoxide poisoning.

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A laser (light amplification of stimulated emission of radiation) is the artificial ray, which is monochromatic, coherent and directional. Laser light with wavelengths of between 600 and 1, 300nm is optimized the depth of penetration in human tissue and is therefore most commonly used in the clinical setting. Low reactive level laser therapy (LLLT), outputting laser light with less than 500mW power, have been recommended for use in rehabilitation because there is some evidence that this form of electromagnetic energy may be biostimulative, facilitate healing and reduce pain. LLLT activates the electron transport chain, increases ATP synthesis, and therefore cause the macrophage, fibroblast and lymphocyte activity. Some studied that LLLT changed the nerve conduction and regeneration and induced vasodilation, particularly of the microcirculation. LLLT is clinically useful in wound healing, musculoskeletal disorders and pain management. The irradiation points are symptomatic pain area, motor points, ganglion, meridian point and so on. Especially irradiation to stellate ganglion and acupuncture points is safe and effective to reduce pain and to improve the peripheral circulation in human. It is difficult to make definitive recommendations for the clinical application of LLLT in rehabilitation, so that we have to study and reveal the mechanism of LLLT effects.

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