In motor learning, the relative frequency of external feedback is the proportion of external feedback presentations divided by the total number of practice trials. In earlier studies, increasing the percentage of body weight loading on the affected leg of hemiplegic patients, external feedback was continuously produced as the patient attempted to perform a movement. This feedback was produced to enhance the learning effect. However, recent studies in nondisabled populations have suggested that compared with 100% relative frequency conditions, practice with lower relative frequencies is more effective. My study compared the effect of 100% relative frequency conditions with 67% relative frequency conditions to determine what effect they exerted on motor learning for increasing the percentage of body weight loading on the affected lower limbs of patients with hemiplegia. Twenty-four hemiplegic patients were randomly assigned to one of two experimental groups. Each group practiced weight transfer motor learning on a machine. During practice, visual feedback was offered to all subjects. The experiment was carried out with full visual feedback for patients in group one but only 67% visual feedback for patients in group two. The percentage of loading on the affected leg was recorded four times: before learning (baseline value), immediately after learning, 30 minutes after learning, 24 hours after learning. The results were as follows: 1. In the 100% visual feedback group, the percentage of loading on the affected leg increased significantly in all three testing modes over the baseline value. 2. In the 67% visual feedback group, the percentage of loading on the affected leg increased significantly in all three measurements. 3. Immediately after learning, the learning effect was not significantly different between the two groups, but was significantly greater after both the 30 minutes delay and the 24 hours period. These results suggest that the 33% reduction in the provision of visual feedback may enhance the learning effect of increasing the percentage of body weight loading on the affected leg in patients with hemiplegia.
The purposes of this study were to determine the effect of different degrees of severity of diabetic neuropathy on balance function, and to evaluate dynamic balance and functional performance in diabetes patients. Twenty-four subjects with diabetes mellitus were divided into three groups according to results of sensory nerve conduction study. All subjects were evaluated for dynamic balance which was measured using computerized dynamic posturography, and functional performance which was measured using the Berg balance scale. One-way analysis of variance was used to determine whether there were any statistically differences of dynamic balance function and functional performance among the three groups. The Spearrnan's rank correlation was used to determine statistical significance between dynamic balance and age. The results were as follows: 1. Dynamic balance measured using computerized dynamic posturography was significantly lower in the no response group than in the normal amplitude group (p<0.05). 2. Functional performance tested by the Berg balance scale was not statistically different among the three groups (p>0.05). 3. an inverse relationship was found between dynamic balance measured using computerized dynamic posturography and age (r=-0.68, p<0.05). These results suggest that patients with severe diabetic neuropathy have loss of dynamic balance function. Therefore, patients with severe diabetic neuropathy need to have their balance evaluated and receive appropriate education.
The purposes of this study were to ascertain differences of the sensory system, central processing system, effector system, and balance ability according to general characteristics (sex, fall experience, and age), and to identify the contributions of the sensory, central processing, and effector system to balance ability in 83 healthy elderly subjects. The subjects were elderly (over 60 years) who live in Wonju City. All subjects participated in six tests (position sense test, visual acuity, vestibular stepping test, Mini-Mental Status Exam-Korea, strength of dorsiflexors, and Berg Balance Test). Collected data were analyzed by the independent t-test, one-way ANOVA, and stepwise multiple regression. The results were as follows: 1. The results of the six tests according to sex showed that vestibular function was significantly better in women than in men. But visual acuity, cognitive function, strength of dorsiflexors, and balance ability were significantly better in men than in women (p<0.05). 2. There were no significant differences in position sense, visual acuity, vestibular function, cognitive function, strength of dorsiflexors, and balance ability between fallers and non-fallers (p>0.05). 3. However, the results of the six tests according to age (group A: 60-69 years, group B: 70-79 years, group C: 80-89 years) showed significant differences in five tests. In the Scheff test, position sense, visual acuity, and cognitive function showed significantly different results between in group A and group C: the strength of the dorsiflexors was significantly different between in group A and group B, and balance ability was significantly different between in group A and group C, and between in group B and group C (p<0.05). 4. Cognitive function and position sense were positively associated with balance ability. Their power of explanation regarding balance ability was 38% (p<0.05). These results suggest that cognitive function and position sense play an important role in balance ability. This would seem to suggest that programs for evaluation or improvement of elderly's balance ability in the elderly should consider cognitive function and position sense.
Noninvasive low intensity ultrasound has been shown to be an effective means of accelerating bone fracture repair in both animal and clinical studies. The effects of ultrasound stimulation on bone repair after fibular osteotomy were assessed in a rabbit fibular fracture model. Bilateral closed fibular fractures were made in skeletally mature male White Japanese rabbits. In this study, 24 subjects were randomly divided into 2 groups: experimental group 1 (n=12), and experimental group 2 (n=12). Experimental group 1 received 0.875 MHz continuous ultrasound and Experimental group 2 was treated with 3 MHz continuous u1trasound. The ultrasound intensity was 50 and treatment time was 10 minutes for every session in both groups. In each rabbit, one fibula served as a control and the other was subjected to ultrasound treatment 5 times per week for 3 weeks. After 3 weeks, rabbits were sacrificed and the ratios of the area between the trabeculae and bone marrow of the fibulae were calculated. At the end of the experimental period, 14 of the 24 rabbits were excluded due to complications from surgery or inadequate fracture status for this study. There was no statistically significant difference in the trabeculae area between experimental leg and control leg in experimental group 1 and experimental group 2 (p>0.05). And there was also no statistic-statistically significant difference between experimental group 1 and experimental group 2 according to ultrasound treatment frequencies, 0.875 MHz and 3 MHz (p>0.05). These data suggest that in Japanese white rabbits, low intensity ultrasound stimulation does not facilitate fracture repair nor is there any difference in fracture repair results between ultrasound frequencies, 0.875 MHz and 3 MHz.
Patients with hemiplegia usually show different body weight distribution as compared with normal subjects. Asymmetrical posture during static stance has been identified as a common problem in patients with hemiplegia. The purpose of this study was to identify the effects of vision and visual feedback on body weight distribution while standing under three conditions: eyes-closed, eyes-open and visual feedback condition. Fourteen patients with hemiplegia participated in the study. Their body weight distribution during standing for 20 seconds was measured by Limloader. The data were analysed by repeated measure of one-way ANOVA. The weight bearing on the paretic limb in the eyes-open condition was significantly higher than that of the eyes-closed condition. The weight bearing on the parietic limb in the visual feedback condition was significantly higher than that of the eyes-open condition. These results suggest that patients with hemiplegia can improve their symmetrical stance ability using visual feedback.
The purpose of this study was to identify vital capacity (VC) in relation to the changing position of 19 patients with spinal cord injury (SCI) and 20 normal controls. Among the 19 SCI patients, there were 9 quadriplegics and 10 paraplegics. The vital capacity was measured in each subject during sitting, standing, lying, and head down position of 30 degrees. The data were analysed by the Kruskal-Wallis test, Mann-Whitney test, and Wilcoxon signed rank test. For the SCI, significant difference of VC accoring to the 4 positions between quadriplegics and paraplegics. In the control group, significant difference of VC according to the 4 positions. In 4 positions the VC of men were significantly larger than that of women between two groups. No statistical significant difference was shown in VC by the postural change between quadriplegics and paraplegics.
The nature of entrainment between the locomotor and the respiratory rhythm was investigated while normal human subjects were walked or running on a treadmill. The purpose of this study was to analyze the incidence and type of coordination between the locomotor and the respiratory rhythm during running at different work load. The experiments were carried out on 12 untrained volunteers exercising at 3 work loads (2 METs, 3 METs, 4 METs in randomized order). The gait cycle was measured by electromyography (EMG) signal of gastrocnemius firing and the respiratory cycle was measured by a thermometer. We found that the ratio between the locomotor and the respiratory rhythm existed and 2:1 ratio between the locomotor-respiratory coupling was dominant at 2 METs and 3 METs
Trunk holding test (Sorensen test) appear to have more value than strength test in prediction the occurrence of low back pain. Electromyographic activity of trunk extensor muscles during these test may provide clues to the etiology of neuromuscular-based low back pain. This study investigated the difference in back muscle endurance between healthy adult men and women using surface electromyographic (EMG) power spectral analysis. Thirty hea1thy subjects (15 men and 15 women) performed an unsupported trunk holding test for 60 seconds. Recording surface electrodes were placed over the erector spinae medially and laterally at vertebral levels of and . Slope of total frequency was evaluated using the MP100WSW Fast Fourier Transform spectrum analysis program. The slopes of all indices of back muscle fatigue, except right , were significantly steeper in men than in women (p<0.05). Our results indicated that the trunk holding test using EMG power spectral analysis of erector spinae muscles is useful for the evaluation of fatigue rate of these muscles. Our results also showed a higher muscle endurance in healthy adult women than in men.
This study examined the rates of spinal abnormal curvature and the correlation of the Body Mass Index (BMI), Low Back Pain (LBP) and spinal curvature by measuring scoliosis, kyphosis, and lordosis in university students. The study population included 67 male, 92 female university students, making a total of 159, in Wonju City. Spinal curvature was measured by an electrogoniometer in a computerized skeletal analysis system. Lateral curvature of spine of more than 10 degrees was considered as nonspostural scoliosis. The correlation of BMI, LBP and the spinal curvature was analysed by Pearson's correlation coefficient and t-test. The following results were obtained: 1. The overall incidence and rate of scoliosis in cases with a greater than 10 degree curve in males was an incidence of 8 and a rate of 11%. In females the incidence was 36 and the rate 39.2%. 2. The overall incidence and rate of kyphosis of less than 20 degrees in males was a rate of 9 and an incidence of 11.9%. In females, the rate was 5 and the incidence 5.4%. In kyphosis cases of more than 40 degrees, the male rate was 5 and the incidence 7.7%. For female the rate was 13 and the incidence 14.2%. 3. The overall incidence and rate of lordosis with curves of less than 20 degrees was a rate of 6 for males and an incidence of 9.0%. For females, the rate was 5 and the incidence 5.4%. In cases of more than 50 degrees lordosis, the female rate was 2 and the incidence 2.2%. There were no males in this category. 4. There was a negative correlation between kyphosis and BMI. The greater the kyphotic curve, the less the BMI in males (p<0.05). There was no significant BMI difference by gender in either scoliosis or lordosis. There was, however, a significantly decreased sacral angle in the female group with LBP. The results of this study cannot be generalized to the general population because the subjects were all from one university. The measurements were quite reliable because the angles determined by the Metrocom System were highly correlated with radiologic findings. This study shows the need for a regular screening system for spinal curvatures in university health examination procedures.