This study was designed to identify the effects of foot position on electromyographic (EMG) activity of the quadriceps femoris during maximum voluntary contraction (MVC) in standing. Twenty young adults who had not experienced any knee injuries were recruited. Their Q-angles were within a normal range. They were asked to stand in five different foot positions ( externally rotated, internally rotated, neutral, plantarflexed, and dorsiflexed foot position). The EMG activities of the vastus lateralis (VL), rectus femoris (RF), and vastus medialis oblique (VMO) were recorded in standing by surface electrodes and normalized by MVC EMG values derived from manual muscle test. The normalized EMG activity levels (%MVC EMG) of muscles in the five foot positions were compared using repeated measures ANOVA. The EMG activity levels of the VL, RF, and VMO were the highest when foot was externally rotated. The EMG activity levels of the VL and RF were significantly different among the foot positions (p<.05). However, EMG activity levels of the VL, RF, VMO, and VMO/VL ratio did not show significant differences in each foot position (p> .05). The results suggest that the quadriceps femoris may be effectively activated by performing MVC at an externally rotated foot position. Therefore, the externally rotated foot position can be considered as an effective foot position for quadriceps femoris strengthening exercise. Further studies are needed to identify whether there are differences in the effects of foot position on muscle strength after MVC exercise of quadriceps femoris in standing.
The purpose of this study was to investigate the effect of donning of a hard insole in patients with hallux valgus. Fourteen subjects were selected from patient with foot pain at Lee Chang-Heon Foot Clinic from August 4, 2000 to September 15, 2000. The hallux valgus angle and the first-second intermetatarsal angle were radiographically measured before and after donning the hard insole. Based on these two kinds of angles, a mild hallux valgus deformity group was characterized by the hallux valgus angle of less than 20 degrees, and a moderate hallux valgus deformity group was characterized by the hallux valgus angle of 20 to 40 degrees. After three weeks with the hard insole donned, the foot angles of the patients with hallux valgus were measured again. The data were analyzed by Wilcoxon signed ranks test, and the following results were obtained: 1) After the trial, both mild hallux valgus deformity group and moderate hallux valgus deformity group demonstrated that the hallux valgus angles were significantly decreased. 2) After the trial, mild hallux valgus deformity group demonstrated that the first-second intermetatarsal angle was significantly decreased. 3) After the trial, moderate hallux valgus deformity group demonstrated that the first-second intermetatarsal angle was not significantly decreased. The above findings revealed that according to donning hard insole, the hallux valgus angles of mild and moderate hallux valgus deformity groups and the first-second intermetatarsal angle of mild hallux valgus deformity group were significantly decreased. The results of this study have some limitation for generalization due to the limited number of subjects. Further studies are needed to evaluate the effect of hard insole on hallux valgus with more precise laboratory equipments and measurements in patients with hallux valgus.
The purpose of this study was to examine the effect of the upper limb nerve mobilization (ULNM) on functional recovery of upper extremity in hemiplegic patients following stroke. Twenty patients who had functional impairment on upper extremity were participated. Subjects were randomly divided into two groups: Control group (n=10) received traditional physical therapy only for 4 weeks; Experimental group (n=10) received ULNM treatment along with traditional physical therapy for the same period. Upper extremity functions were assessed by manual muscle test (MMT), modified Ashworth scale (MAS), and Fugl-Meyer assessment (FMA) before and after the treatment. In both experimental and control group, upper extremity functions were significantly improved in MMT (p<.01) and FMA (p<.01), however only experimental group showed significant improvement in FMA after the treatment (p<.05). Moreover, experimental group showed significantly greater improvement than control group in MMT (p<.05), MAS (p<.05), and FMA (p<.05). We conclude that the upper extremity functions is a useful additional therapeutic technique for the effective treatment of upper extremity deficits in hemiplegic patients.
Fatigue is the decline in force produced as a result of prolonged muscle activity. Localized muscle fatigue can be identified by a shift toward low in the frequency components of the EMG signal, typically represented by a fall in the median frequency. Previous studies show that a shortened muscle develops a higher fatigue than elongated muscles. The purpose of this study was to investigate the time-related change of median frequency and torque during maximal isometric back extension exercises at different exercise angles (, , , ). Twenty healthy subjects (mean age = ) were evaluated in this study. Median frequency was extracted from the EMG signals by fast Fourier transform (FFT). Initial median frequency and the slope of median frequency change over time were computed from linear regression analysis. Pearson's product moment correlation was used to quantify the relationship between slope of median frequency and torque. The results were as follows: 1) Significant differences in y-intercepts of torque regression equation with respect to exercise angle were shown. However, there were no differences in the slopes of the median frequency and torque, and y intercept of the median frequency among exercise angles. 2) There was no significant correlation between slope of median frequency and torque. 3) But there was moderate correlation between median frequency and torque at each exercise angle. In conclusion, the exercise angle during maximal isometric back extension exercise is not a direct effect on slope of median frequency and torque. But results showed that median frequency and torque shift were highly correlated in all subjects.
For spinal flexibility measurements to be meaningful to clinicians or researchers, they must have a normative information and an understanding of how different variables affect spinal range of motion (ROM). Normal spinal ROM measurements are influenced to differing degrees by many factors. These factors include age, gender, time of day, leisure activities, previous history of low back pain, warming up, and the techniques with which normative data are collected. The additional variables of standing height, ratio of standing height to sitting height, and obesity had not been previously studied extensively and were shown to have a significant effect on flexibility in the sagittal plane. These relationship cannot be explained easily. Thus, the purpose of this study was to determine the relationship between spinal flexibility and individual factors (weight, standing height, and ratio of standing height to sitting height) that influence it. Fifteen healthy subjects between the ages of 20 and 27 years were studied. Two physical therapists measured independently the spinal forward bending ROM in the sagittal plane by Remodified Schober test and Finger-to-floor test. In order to determine the statistical significance of the result the Pearson's correlation was applied at the .05 level of significance. The results of this study were as follows: 1) Significant relationship was not identified between spinal flexibility and weight. 2) Significant relationship was not identified between spinal flexibility and standing height. 3) Significant relationship was not identified between spinal flexibility and ratio of standing height to sitting height.
The purpose of this study was to investigate the effect of knee exercises on the onset times of vastus medialis oblique muscle (VMO) and vastus lateralis muscle (VL) and in healthy subjects. Fifteen subjects (7 men, 8 women) in a mean age of 26.4 years participated in the study. Electromyographic (EMG) signals were recorded from the VMO and VL under four exercises. Knee exercises consisted of open kinematic terminal knee extension, straight leg raising, isometric hip adduction exercise, and closed kinematic terminal knee extension. No significant differences were found in the onset times of EMG activities of VMO and VL in the four exercises. There were also no significant differences among the exercises. These results coincided with previous studies that found no difference between onset of VMO and VL. However, it is difficult to say that there is no difference between onset of VMO and VL in healthy subjects. To confirm this results, further researches that follow same on set determination metod and exercises are needed. Not only is the study of onset time of muscle needed, but also the studies of the amount of activation and the rate of increase of muscle activation are needed.
The purpose of this study was to investigate whether the standing balance could be influenced by the different foot positions. Seventeen patients with hemiplegia were tested for the static and dynamic balance under the different foot positions. In the balance test, subject stood by bearing weight on one foot, and the other foot was positioned in three different positions (symmetric, anterolateral, and anterior position). This study used the Kinesthetic ability trainer (KAT2000) to measure the standing balance. The results were as follows: 1) There were significant differences in the static standing balance in different foot positions with both weight-bearing on the paretic limb and on the nonparetic limb (p<.05). 2) There were also significant differences in the dynamic standing balance in different foot positions with both weight-bearing on the paretic limb and on the nonparetic limb (p<.05). 3) There was a significant difference when the paretic weight-bearing and the nonparetic weight-bearing were compared (p<.01). 4) when the paretic weight-bearing and the nonparetic weight-bearing were compared, anterior foot position showed a significant difference in the dynamic standing balance (p<.05), but anterolateral foot position did not show a significant difference (p>.05). In this study, the standing balance showed a significant difference according to different foot positions in hemiparetic patients, and standing balance was better when they stood by bearing weight on the nonparetic limb. These results indicate that it is a necessary to consider both weight-bearing limb and foot position not only in the rehabilitation program but also in achieving the stability in the independent life.
Dexterity is defined in the present study as interdigital manipulative skill or the fine manipulative movements of objects held between the thumb and fingers. The Grooved pegboard test has been used to evaluate dexterity requring visual-motor coordination. The purpose of this study was to standardize the completion time of the Grooved pegboard test in different age groups and gender. Normative values for the Grooved Pegboard Test was developed on the sample of 282 healthy volunteers (89 men and 183 women). Subjects were stratified according to gender and dominant hand and were subdivided into six groups by blocking. The results of this study were as follows: 1) There was a significant difference in completion time between dominant and nondominant hand in both men and women groups (p<.05). 2) There were significant differences in completion time between men and women group (p<.05) 3) There were significant differences in completion time among age groups (p<.05).