ISSN:0894-9115    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

The H reflex in the S1 spinal nerve has been used in electrodiagnosis of S1 radiculopathy for several years. Direct stimulation of the S1 spinal nerve has provided more complete information about the H reflex pathway by dividing it into its peripheral and central (or spinal) conduction portions. A previous study compared spinal nerve latency with the H reflex latency, demonstrating an abnormal S1 ratio in subjects with S1 radiculopathy, thereby suggesting slowing within the spinal segment of the nerve. No study, however, has established a normal value for the central (spinal) portion of the H reflex. We electrodiagnostically tested 20 subjects with normal clinical neurologic and musculoskeletal examinations to define a normal sample of the central loop of the H reflex in the S1 spinal nerve. The peak latencies of the M and H reflex responses were measured after a single stimulus to the S1 spinal nerve. The data obtained established 7 ± 0.3 ms as the normal value for the interpotential latency difference (central loop) of the H reflex in the S1 spinal nerve in healthy subjects. Six patients with clinical and electromyographic evidence of S1 radiculopathy all had central loop latencies of >8 ms. The normal value of the central loop of the H reflex suggested in this pilot investigation may, therefore, be used to allow for earlier and more accurate diagnosis of an acute S1 radiculopathy.

ISSN:0894-9115    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

The H reflex is a monosynaptic reflex whose latency can be used to evaluate pathology of the S1 nerve root and axon. Little has been written about the use of the H reflex amplitude in evaluating S1 nerve physiology. Although amplitude measurement of evoked potentials is useful in the evaluation of other sensory and compound muscle action potentials, this single case study shows it to be an unreliable parameter with which to evaluate the integrity of S1 nerve fibers, because muscle activity in antagonist and agonist affects the amplitude and in some instances abolishes it.

ISSN:0894-9115    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Studying the effect of spinal cord reinforcement maneuvers (SCRMs) on H reflex assists in understanding aspects of motor control. Our objective was as follows: (1) to elucidate the effects of four neck positions (neck resting at neutral position (control); passive hyperflexion of the neck; hyperextension of the neck with simultaneous abdominal contraction; and sustained active neck hyperflexion); (2) to evaluate the temporal changes of soleus H reflexes repeatedly evoked after a period of sustained neck flexion. We used a prospective, intrinsically controlled trial of the effects of these SCRMs on the H reflexes and M-responses in ten healthy volunteers. Pre- and postmaneuver measures included H reflex and M-response latencies and amplitudes, H/M maximum amplitude ratio, and H threshold. The four maneuvers showed no significant effect on the H reflex or M-response measures. To investigate temporal changes in the H reflex amplitude, H reflexes were repeatedly evoked at two-minute intervals after a one-minute period of active neck flexion. The amplitude of the H reflex was enhanced (P= 0.0356; analysis of variance), and the post hoc least significant difference test was significant at four minutes postmaneuver. Peak magnitude of the H reflex occurred at four minutes after relaxation, and the response returned to pretest baseline at eight minutes. The results of this study document the time course of repeated H reflexes after SCRM, and the timing of the H reflex was found to be a contributing variable that should be considered in future study designs.

ISSN:0894-9115    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

We tested the hypothesis that reducing core body temperature in subjects with multiple sclerosis (MS) improves the cortical somatosensory evoked potential (SEP) response. Twenty subjects with definite MS were compared with 20 subjects without neurologic symptoms or disease. SEPs were recorded with stimulation of the tibial and median nerves unilaterally at 3.1 and 6.1 Hz. The procedure was repeated after a cooling vest and hat reduced core body temperature by an average of 0.46 ± 0.28°C. No appreciable change in latency or amplitude of the SEP responses occurred in either the control or MS group with cooling. Although the amplitude of the cortical SEP response was less at the 6.1 Hz rate than at 3.1 Hz, there were no statistically significant differences between the MS and control groups or between stimulation rates with cooling. We conclude that, although some reports suggest symptomatic improvement during cooling in subjects with MS, this improvement may not be associated with changes in the SEP.

ISSN:0894-9115    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

By using a fixed 8-cm distance between the stimulating and recording electrodes, we describe a new approach to peroneal nerve motor conduction studies to the proximal muscles. The recording active electrodes were fastened over the tibialis anterior and peroneus longus, while the stimulating cathode was placed at the posterolateral border of the fibular neck. The skin temperature was maintained at or above 32°C in the lateral surface of the proximal shin. In normal subjects, 81 deep and superficial peroneal nerves were tested to establish reference values. The latencies to the tibialis anterior and peroneus longus were 2.5 ± 0.3 (range, 2-3) ms and 2.6 ± 0.2 (range, 1.9-3) ms, respectively. The amplitudes of compound muscle action potential for deep and superficial peroneal nerves were 6.2 ± 1.3 (range, 3.6-9.3) and 6.2 ± 1.7 (range, 3.4-10.6) mV, respectively. Also, 17 adult onset diabetic patients were tested for comparison. We concluded that this alternative test to the conventional methods is accessible for electrophysiologic evaluation of peroneal neuropathy.

ISSN:0894-9115    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

This is a report of a young boy with the unusual combination of autonomic dysfunction with locked-in syndrome following multiple shunt revisions for hydrocephalus. A review of the literature on autonomic dysfunction syndrome and the complex clinical picture of the combined syndromes in a pediatric patient are discussed. The marked effectiveness of treatment with carbidopa/levodopa over bromocriptine for both syndromes is noted.

ISSN:0894-9115    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Respiratory function and arterial blood gas were examined before and after a two-month exercise program performed in a pool filled with hot spring water in 22 patients (70.9 ± 9.1 years of age) with stable chronic obstructive pulmonary disease (12 cases of bronchial asthma and 10 cases of pulmonary emphysema) treated at our hospital between 1991 and 1994. The ratio of forced expired volume in one second to forced vital capacity (FEV1%) was significantly increased after the exercise program (P< 0.05), whereas the ratio of forced vital capacity to predicted normal value (%FVC) did not change. In addition, a tendency toward an increase in peak flow without an increase in maximum expiratory flow at 25 and 50% (V25and V50) was observed. Although PaO2was not increased, PaCO2was selectively decreased by the exercise program (P< 0.05). The changes in respiratory function and arterial blood gas were considered attributable to respiratory muscle training and small airway clearance. Exercise in a pool filled with hot spring water may be useful in treating chronic obstructive pulmonary disease.

ISSN:0894-9115    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Exercise training programs are usually based on a maximal exercise stress test; however, this test is often difficult and sometimes frightening to older persons. This preliminary study reports on a fixed-distance, submaximal walk test and compares its usefulness for exercise prescription to that of the traditional maximal stress test. Ten cardiac patients, with an average age of 72 years (4 men), had recent clinically indicated maximal graded stress tests. Within one week, each had the walk test, which consisted of walking three times up and back 100 feet in the hospital corridor (total of 600 feet) as rapidly as possible, with a blood pressure cuff on their arm and carrying the electrocardiogram cable. Resting and peak heart rate, blood pressure, symptoms, and exercise electrocardiograms were compared for the walk testvthe maximal stress test. Oxygen consumption was calculated from the peak workload on the maximal stress test and from walking speed on the walk test. The peak heart rates after the walk test were within the target heart rate zone (70-85%) for exercise programming, as obtained from the maximal stress test, in all patients except one. The calculated peak oxygen consumption from the walk test was also within the training zone (60-80%) obtained from the maximal stress test in all patients except one. This pilot study shows that a submaximal, steady state, timed walk of 600 feet can be a feasible method of providing the information for exercise programming, possibly avoiding the need for a maximal stress test. This walk test can be performed easily by health-related staff without sophisticated facilities in an inpatient rehabilitation unit or nursing home; however, further study with a larger number of patients is necessary before this method of exercise prescription can be recommended.

ISSN:0894-9115    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:0894-9115    

出版商:OVID    

年代:1997

数据来源: OVID