Background: Gluteus medius muscle is important for the stability of hip joint. The sufficient core stability can be contributed to the performance of gluteus medius muscle in standing position. In addition, the external support may affect core stability in standing position. Objects: The purpose of this study was to investigated the effectiveness of the external support on the strength and muscle activity of hip abductor muscle during hip abduction in standing position in subjects without core stability. Methods: Fifteen subjects participated in this study. The subjects were evaluated by using the double-leg lowering with bent knees to measure the core stability. The strength and muscle activity of hip abductors was measured in standing position with the condition with and without external support using the tensiometer sensor and the surface electromyography. The paired t-test was used to investigate the difference between hip abductor strength and activity according to external support. The level of statistical significance was set at α = 0.05. Results: The hip abductor strength and muscle activity of gluteus medius muscle with external support were significantly greater than those without external support during hip abduction in standing position (p < 0.05). Conclusion: During hip abduction in standing position, the external support may be contributed to the improvement of the hip abductor strength and muscle activity of gluteus medius especially in the subjects without core stability.

Background: Patients who underwent rotator cuff repair (RCR) require management to control pain and prevent re tear and stiffness. Thoracic mobilization has been applied for the improvement of vertebra and shoulder movements and pain reduction. Also, core stability exercise is an intervention necessary for rehabilitation after shoulder surgery. Objectives: To examine the short term benefits of thoracic mobilization and core stability exercise for patients after RCR. Design: Randomized controlled trial with multi arm parallel group and single blind assessor. Methods: 30 participants after RCR were recruited. Participants were categorized into conventional physical therapy (CPT) group, thoracic mobilization (TM) group, and core stability exercise (CSE) group according to the randomization program. Each treatment, transcutaneous electrical nerve stimuli (TENS), TM, and CSE was applied to each group. 3 physical therapists only conducted evaluations; VAS (visual analogue scale), ROM (range of motion), and Korean version of Shoulder Pain and Disability Index (SPADI). Results: VAS and SPADI were statistically reduced, and ROM was statistically improved in all 3 groups. In between three group comparisons of changes in outcome variables, there was not a significant difference in VAS, but there was a significant difference in ROM and SPADI. In the post hoc test, ROM and SPADI showed a significant difference in TM and CSE compared to CPT. Conclusion: TM according to Maitland concept and CSE had beneficial effects compared to CPT in patients after RCR.

Background: While the formal test has been used to provide a quantitative measurement of core stability, studies have reported inconsistent results regarding its test-retest and intraobserver reliabilities. Furthermore, the validity of the formal test has never been established. Objects: This study aimed to establish the concurrent validity and test-retest reliability of the formal test. Methods: Twenty-two young adults with and without core instability (23.1 ± 2.0 years) were recruited. Concurrent validity was determined by comparing the muscle thickness changes of the external oblique, internal oblique, and transverse abdominal muscle to changes in core stability pressure during the formal test using ultrasound (US) imaging and pressure biofeedback, respectively. For the test-retest reliability, muscle thickness and pressure changes were repeatedly measured approximately 24 hours apart. Electromyography (EMG) was used to monitor trunk muscle activity during the formal test. Results: The Pearson’s correlation analysis showed an excellent correlation between transverse abdominal thickness and pressure biofeedback unit (PBU) pressure as well as internal oblique thickness and PBU pressure, ranging from r = 0.856–0.980, p < 0.05. The test-retest reliability was good, intraclass correlation coefficient (ICC1,2) = 0.876 for the core stability pressure measure and ICC1,2 = 0.939 to 0.989 for the abdominal muscle thickness measure. Conclusion: Our results provide clinical evidence that the formal test is valid and reliable, when concurrently incorporated into EMG and US measurements.

The roof grid of single-layer space frame structure, for Energy Core of Incheon Airport Second Terminal, is very simple and aesthetic, but it is apt to buckle under external force because of mild curvature and complex shape. The object of this study is to estimate the stability of single-layer space frame structures for Energy Core of Incheon Airport Second Terminal with the analytical conditions of structural design. The results show that the buckling load of model(pin-pin, uniform load, rigid joint), that is, the most similar model to the analytical conditions of structural design. was 10.7kN/㎡.

Core stability exercises for patients with hemiplegia have become increasingly important and a variety of exercises have been developed over the years to give the hemiplegic patients more stable postural control. This study examined the therapeutic effects of the core stability exercises on the ability of static and dynamic postural control. Fifteen hemiplegic patients (7 males, 8 females, age ranging from 46 to 76 years) hospitalized in a Daejoen rehabilitation hospital were enrolled in this study. Nine and 6 patients had a cerebral infarction and cerebral hemorrhage, respectively. The subjects participated in a core stability exercise program consisting of a total of 12 sessions 3 times each week over a 4-week period with each exercise lasting approximately 15 minutes. The ability of static and dynamic postural control by Berg Balance Scale (BBS) and Timed Up and Go (TUG), respectively, were measured before and after the core stability exercise. A Wilcoxon signed ranks test was used to compare the effects of the ability of static and dynamic postural control before and after core stability exercise in patients with hemiplegia. The =.05 level of significance was used for the statistical tests. Core stability exercises were effective in improving the ability of static postural control; BBS (p<.05). Core stability exercises were also effective in improving the ability of dynamic postural control; TUG (p<.05). Overall, core stability exercise is believed to be an important therapeutic method in rehabilitation programs for hemiplegic patients.