No abstract available.
Humans ; Posture*

BACKGROUND: Low back pain (LBP) is a major problem for office workers. Individuals adopting poor postures during prolonged sitting have a considerably increased risk of experiencing LBP. This study aimed to investigate seat pressure distribution characteristics, i.e., average pressure, peak pressure ratio, frequency of postural shift, and body perceived discomfort (BPD), during 1 hour of sitting among office workers with and without chronic LBP. METHODS: Forty-six participants (chronic LBP = 23, control = 23) typed a standardized text passage at a computer work station for an hour. A seat pressure mat device was used to collect the seat pressure distribution data. Body discomfort was assessed using the Body Perceived Discomfort scale. RESULTS: Office workers with chronic LBP sat significantly more asymmetrically than their healthy counterparts. During 1-hour sitting, all workers appeared to assume slumped sitting postures after 20 minutes of sitting. Healthy workers had significantly more frequent postural shifts than chronic LBP workers during prolonged sitting. CONCLUSION: Different sitting characteristics between healthy and chronic LBP participants during 1 hour of sitting were found, including symmetry of sitting posture and frequency of postural shift. Further research should examine the roles of these sitting characteristics on the development of LBP.
Low Back Pain* ; Posture

As radiation is irradiated from various directions in intensity modulated radiation therapy (IMRT), longer treatment time than conventional treatment method is taken. In case of the patients who have problem to keep same posture for long time because of pain and injury, reducing treatment time through increased dose rate is a way for effective treatment. This study measured and found out the variation of dose and dose distribution in accordance with dose rate variation. IMRT treatment plan was set up to investigate from 5 directions - 0degrees, 72degrees, 144degrees, 216degrees, 288degrees - using ECLIPSE system (Varian, SomaVision 6.5, USA). To confirm dose and dose rate in accordance with dose rate variation, dose rate was set up as 100, 300, 500 MU/min, and dose and dose distribution were measured using ionization chamber (PTW, TN31014) and film dosimeter (EDR2, Kodak). At this time, film dosimeter was inserted into acrylic phantom, then installed to run parallel with beam's irradiating direction, 21EX-S (Varian, USA) was utilized as linear accelerator for irradiation. The measured film dosimeter was analyzed using VXR-16 (Vidar System Corporation) to confirm dose distribution.
Humans ; Particle Accelerators ; Posture

Dyspnea ; etiology ; Humans ; Posture

No abstract available.
Neck* ; Posture* ; Rabbits*

This study was designed to examine relations between posture and size of the tongue and dentoalveolar pattern. The sample was consisted of three groups, the 34 subjects of Normal occlusion, the 31 sub?jects of Bimaxillary protrusion and the 31 subjects of Class III malocclusion. On the cephalograms, lengths, heights and areas of the tongue and intermaxillary space and on the study model, arch length, intercanine width, intermolar width and palatal height were measured. These data from measuring cephalograms and models were statistically analyzed. The results of the study were as follows, 1. Length of the tongue was the greatest in Bimaxillary protrusion and in order of Normal occlusion and Class III malocclusion. 2. Posture of the tongue was the lowest in Class III malocclusion and in order of Bimaxillary protrusion and Normal occlusion. 3. There were a tendency to be larger area of tongue and intermaxillary space in Class III malocclusion compared to Normal occlusion and Bimaxillary protrusion. 4. Size of the tongue and intermaxillary space showed low correlations with the dentoalveolar pattern.
Malocclusion ; Posture* ; Tongue*

The purpose of this study was to compare the degree of vertical head rotation and to evaluate the reproducibility of natural head posture (NHP) according to two guiding methods, the head posture aligner (HPA) method and the self balance posture (SBP) method. The subjects consisted of 30 adults. On the first day, lateral and frontal cephalometric radiographs were obtained through the two guiding methods. One month later, lateral and frontal cephalometric radiographs were obtained again through both guiding methods. The degrees of vertical head rotation of both guiding methods were compared and the reproducibility was evaluated for each guiding method. A comparison of the degrees of vertical head rotation for the two methods revealed that the vertical head posture was lower in the SBP method than in the HPA method by an average of 2.79 degrees. All measurements obtained using the HPA and SBP methods with a time interval of one month did not show any significant difference in lateral and frontal cephalometric radiographs. The results of the present study suggest that the SBP method may be used as an alternative to the HPA method in case the HPA method can not be applied.
Adult ; Head* ; Humans ; Posture*

PURPOSE: The paper presents an intervention for clinical applications in the future by examining the effects of 3D stabilization exercise on patients with lumbar instability, which causes problems in the muscles and balance, and analyzing the effects of balanced lumbar muscles on the static balance. METHODS: After collecting samples randomly from thirty patients with lumbar instability, fifteen patients selected for 3D stabilization exercise were placed in the stability group and fifteen patients selected for Swiss ball exercise were placed in the ball exercise group. The intervention program was applied for thirty minutes a session, once a day, three days a week for four weeks. Before the intervention, the lumbar muscle activity and static balance were measured. After four weeks, they were re-measured in the same way and the data were analyzed. RESULTS: In relation to the within-group changes in muscle activity, all groups except for the LEO and REO groups showed significant differences. Regarding the between-group changes in muscle activity depending on the left and right difference, ES, RA, and TrA but not EO showed significant differences. In addition, there were significant differences in the between-group change in static balance. CONCLUSION: 3D stabilization exercise improves the muscle activity by promoting a balanced posture of lumbar muscles and changing senses, such as a proprioceptor but this had a positive influence on the static balance by controlling the balance of muscles.
Humans ; Muscles ; Posture

PURPOSE: This study examined the influence of longitudinal arch on the strength and muscle activity of the abductor hallucis in the standing position in subjects with and without navicular drop signs. METHODS: A sample of 34 subjects with and without navicular drop signs between 22 and 28 years of age were enrolled in this study. The strength and muscle activity of the abductor hallucis was measured using a tensiometer. The Smart KEMA System and electromyography device was used on the subjects with and without navicular drop signs. Two groups were classified using the navicular drop test to identify the longitudinal arch of the foot. The strength of the abductor hallucis was evaluated in standing, both with and without an external arch support condition. The two-way mixed ANOVA was used. The level of statistical significance was set to α=0.05. RESULTS: The strength and muscle activity of the abductor hallucis in standing was significantly higher with external arch support than that without the external arch support in the group with navicular drop signs. There was no significant difference in the abductor hallucis strength and muscle activity with and without external arch support in the subjects without navicular drop signs. CONCLUSIONS: The strength and muscle activity of the abductor hallucis in standing can be influenced by the external arch support in the group with navicular drop signs. The strength measurement of the abductor hallucis in standing should be separately performed in conditions with and without longitudinal arch of foot.
Electromyography ; Foot ; Posture

To observe the change in the status of stresses according to three different postural angulation of an intervertebral disc with or without nucleus pulposus, 6 specimens of a 3-dimensional photoelastic model of the spine were made of epoxy. The nucleus pulposus portion was replaced with silicon in three models, and the three were made without silicon. Through axial application of a vertical compressive load of 8 kg, the peculiar patterns of the isochromatic fringes were observed. Stresses on the intervertebral disc were analyzed according to three different postural angulations of the intervertebral disc with the nucleus pulposus and without the nucleus pulposus. The results of these study are as follow: 1. In an erect neutral posture with the nucleus pulposus, the stress concentration was much increased at the posterior portion rather than at the anterior portion. Also, the high stress was concentrated at the medial and central portion. In an erect neutral posture without the nucleus pulposus, the stress concentration was much increased at the anterior portion rather than at the posterior portion and the stress distribution seemed to be locally concentrated. 2. In a maximal flexed posture, the stress concentration was much increased at the posterior portion rather than at the anterior portion. Comparing the presence of the nucleus pulposus with the absence of the nucleus pulposus, the stress concentration was lower at the anterior portion in the presence of the nucleus pulposus than in the absence of the nucleus pulposus. However, the stress distribution at the posterior portion was nearly same in the two groups. According to the analysis of the stress distribution diagram, as a whole, the stress pattern around the disc was evenly distributed. 3. In a maximal extended posture, the higher concentration of the stress distribution at the anterior and medial portion rather than in the posterior and lateral portion was observed. The stress concentration was higher in the presence of the nucleus pulposus than in the absence of the nucleus pulposus. 4. Comparing the maximal flexed posture with the erect neutral posture, the stress concentration in the flexed posture was much decreased in the posterior portion rather than in the erect neutral posture, and an even distribution of the stress pattern in the flexed posture was observed. 5. In the presence of the nucleus pulposus, at the anterior and posterior portion, the stress concentration in the flexed posture was much decreased compared with the extended posture. In the absence of the nucleus pulposus, at the anterior and posterior portion, the stress concentration in the extended posture was much decreased compared with the flexed posture.
Intervertebral Disc* ; Posture ; Silicon ; Spine