Effects of posture on postoperative pulmonary function

DEFF Research Database (Denmark)

Nielsen, K G; Holte, Kathrine; Kehlet, H

2003-01-01

BACKGROUND: Pulmonary morbidity is still a relevant complication to major surgery despite improvements in surgical technique and anaesthetic methods. Postoperative posture may be a pathogenic factor, but the effects of changes in postoperative posture on pulmonary function have not been reviewed....... METHODS: Review of controlled, clinical trials evaluating postoperative pulmonary function in patients positioned in the supine vs. the sitting or standing position and patients positioned in the supine vs. the lateral position. Data were obtained from a search in the Medline and Cochrane databases (1966...

The effects of healthy aging on cerebral hemodynamic responses to posture change

International Nuclear Information System (INIS)

Edlow, Brian L; Greenberg, Joel H; Detre, John A; Kim, Meeri N; Durduran, Turgut; Zhou, Chao; Yodh, Arjun G; Putt, Mary E

2010-01-01

Aging is associated with an increased incidence of orthostatic hypotension, impairment of the baroreceptor reflex and lower baseline cerebral blood flow. The effect of aging on cerebrovascular autoregulation, however, remains to be fully elucidated. We used a novel optical instrument to assess microvascular cerebral hemodynamics in the frontal lobe cortex of 60 healthy subjects ranging from ages 20–78. Diffuse correlation spectroscopy (DCS) and near-infrared spectroscopy (NIRS) were used to measure relative cerebral blood flow (rCBF), total hemoglobin concentration (THC), oxyhemoglobin concentration (HbO 2 ) and deoxyhemoglobin concentration (Hb). Cerebral hemodynamics were monitored for 5 min at each of the following postures: head-of-bed 30°, supine, standing and supine. Supine-to-standing posture change caused significant declines in rCBF, THC and HbO 2 , and an increase in Hb, across the age continuum (p < 0.01). Healthy aging did not alter postural changes in frontal cortical rCBF (p = 0.23) and was associated with a smaller magnitude of decline in HbO 2 (p < 0.05) during supine-to-standing posture change. We conclude that healthy aging does not alter postural changes in frontal cortical perfusion

Assessing Somatosensory Utilization during Unipedal Postural Control.

Science.gov (United States)

Goel, Rahul; De Dios, Yiri E; Gadd, Nichole E; Caldwell, Erin E; Peters, Brian T; Reschke, Millard F; Bloomberg, Jacob J; Oddsson, Lars I E; Mulavara, Ajitkumar P

2017-01-01

Multisensory-visual, vestibular and somatosensory information is integrated for appropriate postural control. The primary goal of this study was to assess somatosensory utilization during a functional motor task of unipedal postural control, in normal healthy adults. Assessing individual bias in the utilization of individual sensory contributions during postural control may help customization of rehabilitation protocols. In this study, a test paradigm of unipedal stance control in supine orientation with and without vision was assessed. Postural control in this test paradigm was hypothesized to utilize predominantly contributions of somatosensory information from the feet and ankle joint, with minimal vestibular input. Fourteen healthy subjects "stood" supine on their dominant leg while strapped to a backpack frame that was freely moving on air-bearings, to remove available otolith tilt cues with respect to gravity that influences postural control when standing upright. The backpack was attached through a cable to a pneumatic cylinder that provided a gravity-like load. Subjects performed three trials each with Eyes-open (EO) and Eyes-closed (EC) while loaded with 60% body weight. There was no difference in unipedal stance time (UST) across the two conditions with EC condition challenging the postural control system greater than the EO condition. Stabilogram-diffusion analysis (SDA) indicated that the critical mean square displacement was significantly different between the two conditions. Vestibular cues, both in terms of magnitude and the duration for which relevant information was available for postural control in this test paradigm, were minimized. These results support our hypothesis that maintaining unipedal stance in supine orientation without vision, minimizes vestibular contribution and thus predominantly utilizes somatosensory information for postural control.

Posture-specific phantoms representing female and male adults in Monte Carlo-based simulations for radiological protection

Science.gov (United States)

Cassola, V. F.; Kramer, R.; Brayner, C.; Khoury, H. J.

2010-08-01

Does the posture of a patient have an effect on the organ and tissue absorbed doses caused by x-ray examinations? This study aims to find the answer to this question, based on Monte Carlo (MC) simulations of commonly performed x-ray examinations using adult phantoms modelled to represent humans in standing as well as in the supine posture. The recently published FASH (female adult mesh) and MASH (male adult mesh) phantoms have the standing posture. In a first step, both phantoms were updated with respect to their anatomy: glandular tissue was separated from adipose tissue in the breasts, visceral fat was separated from subcutaneous fat, cartilage was segmented in ears, nose and around the thyroid, and the mass of the right lung is now 15% greater than the left lung. The updated versions are called FASH2_sta and MASH2_sta (sta = standing). Taking into account the gravitational effects on organ position and fat distribution, supine versions of the FASH2 and the MASH2 phantoms have been developed in this study and called FASH2_sup and MASH2_sup. MC simulations of external whole-body exposure to monoenergetic photons and partial-body exposure to x-rays have been made with the standing and supine FASH2 and MASH2 phantoms. For external whole-body exposure for AP and PA projection with photon energies above 30 keV, the effective dose did not change by more than 5% when the posture changed from standing to supine or vice versa. Apart from that, the supine posture is quite rare in occupational radiation protection from whole-body exposure. However, in the x-ray diagnosis supine posture is frequently used for patients submitted to examinations. Changes of organ absorbed doses up to 60% were found for simulations of chest and abdomen radiographs if the posture changed from standing to supine or vice versa. A further increase of differences between posture-specific organ and tissue absorbed doses with increasing whole-body mass is to be expected.

The influence of body posture on lithium clearance

DEFF Research Database (Denmark)

Kamper, A L; Strandgaard, S; Holstein-Rathlou, N H

1988-01-01

measured four times at 1-week intervals: two in the supine and one in the sitting position, and one when the subject was walking around. Glomerular filtration rate was not influenced by posture changes. On the contrary, lithium clearance, which in the supine position was 30 +/- 9 ml/min (1 SD), tended...... during moderate physical activity. Hence, when renal tubular function is studied with the lithium clearance method, standardization of posture and physical activity is important. In such studies physical activity such as walking should particularly be avoided....

[Usefulness of a protocol for carotid sinus massage in supine and erect postures in patients with syncope without other cardiovascular or neurological diseases].

Science.gov (United States)

Bocchiardo, M; Alciati, M; Buscemi, A; Cravetto, A; Richiardi, E; Gaita, F

1995-05-01

Carotid sinus massage is a first level test when investigating the cause of syncope. It is normally performed in the supine and erect positions. However, there is no standard complete protocol. So we have devised a new protocol to evaluate the utility of carotid sinus massage in different postures and the influence of patients age on the response. Two groups of subjects were selected: a group of 167 patients (mean age 50 ys +/- 18, 105 males, 62 females) with a history of syncope without cardiovascular and neurological disease and 20 asymptomatic control subjects (mean age 52 ys +/- 13, 11 males, 9 females). Carotid sinus massage was performed supine, just after passive tilt, after 5 minutes of tilt and just after passive return to supine. If a pause > 3" was detected, the protocol was repeated after atropine i.v. injection. Borderline vasodepressor: blood pressure reduction > 30 but blood pressure reduction > 50 mm Hg or > 30 mm Hg with symptoms like dizziness, vertigo or syncope; cardioinhibitory: pause > 3"; mixed: cardioinhibitory with blood pressure reduction > 30 mm Hg after atropine. Carotid sinus massage gave all informations in the supine position in 14 (12%) patients, after passive tilt in 67 (57%), after 5 minutes of tilt in 30 (26%), and after return to supine in 6 (5%). The responses were: 13 (8%) borderline vasodepressor, 32 (19%) vasodepressor, 2 (1%) cardioinhibitory, 70 (42%) mixed, 50 (30%) negative. Positive responses were more frequent in patients over 45 years (90% versus 43%). In the control group only 3 (15%) positive responses were elicited (2 borderline vasodepressor, and 1 vasodepressor, all in subjects over 45). This protocol for carotid sinus massage evidenced positive responses in 70% of patients with syncope without cardiovascular and neurological disease; cardioinhibitory responses are rare (2%); positive responses are more frequent in patients over 45 years; the protocol specificity was 85%.

The effects of the contract-relax-antagonist-contract form of proprioceptive neuromuscular facilitation stretching on postural stability.

Science.gov (United States)

Ryan, Edwin E; Rossi, Mark D; Lopez, Richard

2010-07-01

To investigate the effects of the contract-relax-antagonist-contract (CRAC) form of proprioceptive neuromuscular facilitation (PNF) stretching, with and without a warm-up, on postural stability. Thirty volunteers (15 men and 15 women, age: 25.17 +/- 5.4 years, height: 173.76 +/- 8.2 cm, and weight: 72.03 +/- 14.87 kg) were randomly assigned to 1 of 3 conditions: warm-up and stretch (WS), stretching only (SO), and a control condition (CON). Contract-relax-antagonist-contract PNF of the hamstrings, plantar flexors, and hip flexors was performed during WS and SO. A 6-minute treadmill warm-up was applied before CRAC in the WS condition. Measures of anterior/posterior and medial/lateral (M/L) postural stability were taken before and after treatment conditions. A 2 x 3 analysis of variance was used to assess for differences between conditions. Significance was set at p Contract-relax-antagonist-contract form of stretching is a useful protocol for improving M/L stability.

Interactive effect of body posture on exercise-induced atrial natriuretic peptide release.

Science.gov (United States)

Ray, C A; Delp, M D; Hartle, D K

1990-05-01

The purpose of this investigation was to test the hypothesis that supine exercise elicits a greater atrial natriuretic peptide (ANP) response than upright exercise because of higher atrial filling pressure attained in the supine posture. Plasma ANP concentration ([ANP]) was measured during continuous graded supine and upright exercise in eight healthy men at rest after 4 min of cycling exercise at 31, 51, and 79% of posture-specific peak oxygen uptake (VO2 peak), after 2 min of cycling at posture-specific VO2 peak, and 5 and 15 min postexercise. [ANP] was significantly increased (P less than 0.05) above rest by 64, 140, and 228% during supine cycling at 51 and 79% and VO2 peak, respectively. During upright cycling, [ANP] was significantly increased (P less than 0.05) at 79% (60%) and VO2 peak (125%). After 15 min of postexercise rest, [ANP] remained elevated (P less than 0.05) only in the supine subjects. [ANP] was 63, 79, and 75% higher (P less than 0.05) in the supine than in the upright position during cycling at 51 and 79% and VO2 peak. Systolic, diastolic, and mean blood pressures were not significantly (P greater than 0.05) different between positions in all measurement periods. Heart rates were lower (P less than 0.05) in the supine position compared with the upright position. In conclusion, these results suggest that supine exercise elicits greater ANP release independent of blood pressure and heart rate but presumably caused by greater venous return, central blood volume, and concomitant atrial filling pressure and stretch.

Assessing Somatosensory Utilization during Unipedal Postural Control

OpenAIRE

Goel, Rahul; De Dios, Yiri E.; Gadd, Nichole E.; Caldwell, Erin E.; Peters, Brian T.; Reschke, Millard F.; Bloomberg, Jacob J.; Oddsson, Lars I. E.; Mulavara, Ajitkumar P.

2017-01-01

Multisensory—visual, vestibular and somatosensory information is integrated for appropriate postural control. The primary goal of this study was to assess somatosensory utilization during a functional motor task of unipedal postural control, in normal healthy adults. Assessing individual bias in the utilization of individual sensory contributions during postural control may help customization of rehabilitation protocols. In this study, a test paradigm of unipedal stance control in supine orie...

Validity and reliability of a dental operator posture assessment instrument (PAI).

Science.gov (United States)

Branson, Bonnie G; Williams, Karen B; Bray, Kimberly Krust; Mcllnay, Sandy L; Dickey, Diana

2002-01-01

Basic operating posture is considered an important occupational health issue for oral health care clinicians. It is generally agreed that the physical posture of the operator, while providing care, should be such that all muscles are in a relaxed, well-balanced, and neutral position. Postures outside of this neutral position are likely to cause musculoskeletal discomfort. To date, the range of the neutral operator position has not been well-defined; nor have any specific instruments been identified that can quantitatively or semi-quantitatively assess dental operator posture. This paper reports on the development of an instrument that can be used to semi-quantitatively evaluate postural components. During the first phase of the study, an expert panel defined the basic parameters for acceptable, compromised, and harmful operator postures and established face validity of a posture assessment instrument (PAI). During the second phase, the PAI was tested for reliability using generalizability theory. Four raters tested the instrument for reliability. Overall, total PAI scores were similar amongst three of the raters, with the fourth rater's scores being slightly greater than the other three. The main effect of the rater on individual postural components was moderate, indicating that rater variance contributed to 11.9% of total variance. The PAI measures posture as it occurs and will have numerous applications when evaluating operator performance in the dental and dental hygiene education setting. Also, the PAI will prove useful when examining the effects of operator posture and musculoskeletal disorders.

Relaxation Mechanisms, Structure and Properties of Semi-Coherent Interfaces

Directory of Open Access Journals (Sweden)

Shuai Shao

2015-10-01

Full Text Available In this work, using the Cu–Ni (111 semi-coherent interface as a model system, we combine atomistic simulations and defect theory to reveal the relaxation mechanisms, structure, and properties of semi-coherent interfaces. By calculating the generalized stacking fault energy (GSFE profile of the interface, two stable structures and a high-energy structure are located. During the relaxation, the regions that possess the stable structures expand and develop into coherent regions; the regions with high-energy structure shrink into the intersection of misfit dislocations (nodes. This process reduces the interface excess potential energy but increases the core energy of the misfit dislocations and nodes. The core width is dependent on the GSFE of the interface. The high-energy structure relaxes by relative rotation and dilatation between the crystals. The relative rotation is responsible for the spiral pattern at nodes. The relative dilatation is responsible for the creation of free volume at nodes, which facilitates the nodes’ structural transformation. Several node structures have been observed and analyzed. The various structures have significant impact on the plastic deformation in terms of lattice dislocation nucleation, as well as the point defect formation energies.

Central haemodynamics in patients with severe postural hypotension

DEFF Research Database (Denmark)

Mehlsen, J; Haedersdal, C; Trap-Jensen, J

1991-01-01

Central haemodynamics in the supine and head-up tilted positions were studied in 24 patients with severe postural hypotension with and without supine hypertension. Results were compared with those obtained in eight normotensive and eight untreated hypertensive controls. In the supine position...... the patients had higher vascular resistances, lower stroke volumes and longer left ventricular ejection time indexes compared to controls, whereas left ventricular ejection fractions did not differ significantly. The patients with supine hypertension had significantly higher vascular resistance compared...... to those with supine normotension. The highest supine blood pressure levels were found in patients with multiple system atrophy. During tilt, vascular resistance and heart rates were increased and stroke volumes and left ventricular ejection time indexes were decreased in the controls. The patients were...

Ambulatory monitoring of left ventricular function in patients with Parkinson`s disease and postural hypotension

Energy Technology Data Exchange (ETDEWEB)

Nappi, A. [Dept. of Nuclear Medicine, Univ. ``Federico II``, Naples (Italy); Cuocolo, A. [Dept. of Nuclear Medicine, Univ. ``Federico II``, Naples (Italy); Iazzetta, N. [Inst. of Internal Medicine and Metabolic Diseases, Univ. ``Federico II``, Naples (Italy); Ferrara, L.A. [Inst. of Internal Medicine and Metabolic Diseases, Univ. ``Federico II``, Naples (Italy); Marotta, T. [Inst. of Internal Medicine and Metabolic Diseases, Univ. ``Federico II``, Naples (Italy); Pace, L. [Dept. of Nuclear Medicine, Univ. ``Federico II``, Naples (Italy); Nicolai, E. [Dept. of Nuclear Medicine, Univ. ``Federico II``, Naples (Italy); De Michele, G. [Inst. of Neurological Sciences, Univ. ``Federico II``, Naples (Italy); Campanella, G. [Inst. of Neurological Sciences, Univ. ``Federico II``, Naples (Italy); Salvatore, M. [National Cancer Inst., Naples (Italy); Postiglione, A. [Inst. of Internal Medicine and Metabolic Diseases, Univ. ``Federico II``, Naples (Italy)

1994-12-01

Left ventricular (LV) function was continuously monitored using a radionuclide detector (VEST) after intravenous injection of 25 mCi technetium-99m labelled red blood cells in nine patients with Parkinson`s disease and postural hypotension (group 1) and ten patients with Parkinson`s disease but without postural hypotension (group 2). LV function and blood pressure were monitored in the supine position for 15 min (period A), upon changing posture from the supine to the upright position for 10 min (period B), and upon returning to the supine position for 10 min (period C). In group 1, the passage from period A to period B induced a significant decrease in end-diastolic volume, end-systolic volume and ejection fraction (all P<0.01). In group 2, ejection fraction increased (P<0.05) upon changing posture from the supine to the upright position. Ejection fraction (F=33, P<0.01), end-diastolic volume (F=9, P<0.05) and end-systolic volume (F=10, P<0.05) were significantly different between the two groups. In group 1, stroke volume, cardiac output and vascular peripheral resistance decreased from period A to period B (all P<0.001). In group 2, no changes in stroke volume, cardiac output and vascular peripheral resistance were observed from period A to period B. All parameters were similar in the two groups during the periods A and C. Upon changing posture from the supine to the upright position, patients with Parkinson`s disease and postural hypotension showed marked changes in parameters of LV function induced by vascular abnormalities. The results of this study may help to clarify the potential risk of sudden postural changes in such patients, which may cause fainting, syncope and increased risk of ischaemic coronary and cerebrovascular attacks and of lower limb fractures. (orig.)

Postural Effect on Renal Function In Cases of Pregnancy-Induced Hypertension

OpenAIRE

丸山, 晋司; Maruyama, Shinji

1989-01-01

Postual effect on renal function was analysed on the cases of pregnancy-induced hypertension (PIH) (n=11) compared with cases of normotensive pregnancies (n=12) and non-pregnant women (n=9). In non-pregnant women, GFR, RBF and RPF showed no changes in relation to the changing posture (supine and left lateral). In normal pregnant women and cases of PIH, GFR, RBF and RPF significantly increased on changing their posture from supine to left lateral at third trimester. Especially, patients with P...

Video-assisted thoracic surgery for superior posterior mediastinal neurogenic tumour in the supine position

Directory of Open Access Journals (Sweden)

Darlong Laleng

2009-01-01

Full Text Available Video-assisted thoracic surgery (VATS for a superior posterior mediastinal lesion is routinely done in the lateral decubitus position similar to a standard thoracotomy using a double-lumen endotracheal tube for one-lung ventilation. This is an area above the level of the pericardium, with the superior thoracic opening as its superior limit and its inferior limit at the plane from the sternal angle to the level of intervertebral disc of thoracic 4 to 5 vertebra lying behind the great vessels. The lateral decubitus position has disadvantages of the double-lumen endotracheal tube getting malpositioned during repositioning from supine position to the lateral decubitus position, shoulder injuries due to the prolonged abnormal fixed posture and rarer injuries of the lower limb. There is no literature related to VATS in the supine position for treating lesions in the posterior mediastinum because the lung tissue falls in the dependent posterior mediastinum and obscures the field of surgery; however, VATS in the supine position is routinely done for lesions in the anterior mediastinum and single-stage bilateral spontaneous pneumothorax. Thus, in the selected cases, ′VATS in supine position′ allows an invasive procedure to be completed in the most stable anatomical posture.

Semi-recumbent position versus supine position for the prevention of ventilator-associated pneumonia in adults requiring mechanical ventilation.

Science.gov (United States)

Wang, Li; Li, Xiao; Yang, Zongxia; Tang, Xueli; Yuan, Qiang; Deng, Lijing; Sun, Xin

2016-01-08

Ventilator-associated pneumonia (VAP) is associated with increased mortality, prolonged length of hospital stay and increased healthcare costs in critically ill patients. Guidelines recommend a semi-recumbent position (30º to 45º) for preventing VAP among patients requiring mechanical ventilation. However, due to methodological limitations in existing systematic reviews, uncertainty remains regarding the benefits and harms of the semi-recumbent position for preventing VAP. To assess the effectiveness and safety of semi-recumbent positioning versus supine positioning to prevent ventilator-associated pneumonia (VAP) in adults requiring mechanical ventilation. We searched CENTRAL (2015, Issue 10), which includes the Cochrane Acute Respiratory Infections Group's Specialised Register, MEDLINE (1946 to October 2015), EMBASE (2010 to October 2015), CINAHL (1981 to October 2015) and the Chinese Biomedical Literature Database (CBM) (1978 to October 2015). We included randomised controlled trials (RCTs) comparing semi-recumbent versus supine positioning (0º to 10º), or RCTs comparing alternative degrees of positioning in mechanically ventilated patients. Our outcomes included clinically suspected VAP, microbiologically confirmed VAP, intensive care unit (ICU) mortality, hospital mortality, length of ICU stay, length of hospital stay, duration of ventilation, antibiotic use and any adverse events. Two review authors independently and in duplicate screened titles, abstracts and full texts, assessed risk of bias and extracted data using standardised forms. We calculated the mean difference (MD) and 95% confidence interval (95% CI) for continuous data and the risk ratio (RR) and 95% CI for binary data. We performed meta-analysis using the random-effects model. We used the grading of recommendations, assessment, development and evaluation (GRADE) approach to grade the quality of evidence. We included 10 trials involving 878 participants, among which 28 participants in two

Effects of posture on upper and lower limb peripheral resistance following submaximal cycling.

Science.gov (United States)

Swan, P D; Spitler, D L; Todd, M K; Maupin, J L; Lewis, C L; Darragh, P M

1989-09-01

The purpose of this study was to determine postural effects on upper and lower limb peripheral resistance (PR) after submaximal exercise. Twelve subjects (six men and six women) completed submaximal cycle ergometer tests (60% age-predicted maximum heart rate) in the supine and upright seated positions. Each test included 20 minutes of rest, 20 minutes of cycling, and 15 minutes of recovery. Stroke volume and heart rate were determined by impedance cardiography, and blood pressure was measured by auscultation during rest, immediately after exercise, and at minutes 1-5, 7.5, 10, 12.5, and 15 of recovery. Peripheral resistance was calculated from values of mean arterial pressure and cardiac output. No significant (p less than 0.05) postural differences in PR were noted during rest for either limb. Immediately after exercise, PR decreased (55% to 61%) from resting levels in both limbs, independent of posture. Recovery ankle PR values were significantly different between postures. Upright ankle PR returned to 92% of the resting level within four minutes of recovery, compared to 76% of the resting level after 15 minutes in the supine posture. Peripheral resistance values in the supine and upright arm were not affected by posture and demonstrated a gradual pattern of recovery similar to the supine ankle recovery response (85% to 88% of rest within 15 minutes). The accelerated recovery rate of PR after upright exercise may result from local vasoconstriction mediated by a central regulatory response to stimulation from gravitational pressure on lower body circulation.

Influence of Functional Head Postures on the Dynamic Functional ...

African Journals Online (AJOL)

Background: The dentist utilizes supine position during therapeutic procedures, while the patients assumes extended head posture during mastication. It is critical for the restorative dentist to evaluate and understand the possible effect of change in head posture on occlusal contacts. An understanding of the possible effect ...

Relationship between antigravity control and postural control in young children.

Science.gov (United States)

Sellers, J S

1988-04-01

The purposes of this study were 1) to determine the relationship between antigravity control (supine flexion and prone extension) and postural control (static and dynamic balance), 2) to determine the quality of antigravity and postural control, and 3) to determine whether sex and ethnic group differences correlate with differences in antigravity control and postural control in young children. I tested 107 black, Hispanic, and Caucasian children in a Head Start program, with a mean age of 61 months. The study results showed significant relationships between antigravity control and postural control. Subjects' supine flexion performance was significantly related to the quantity and quality of their static and dynamic balance performance, whereas prone extension performance was related only to the quality of dynamic balance performance. Quality scale measurements (r = .90) indicated that the children in this study had not yet developed full antigravity or postural control. The study results revealed differences between sexes in the quality of static balance and prone extension performance and ethnic differences in static balance, dynamic balance, and prone extension performance.

Is the modified Tardieu scale in semi-standing position better associated with knee extension and hamstring activity in terminal swing than the supine Tardieu?

NARCIS (Netherlands)

Faber, I.R.; Nienhuis, B.; Rijs, N.P.; Geurts, A.C.H.; Duysens, J.E.J.

2008-01-01

The aim of this study was to investigate whether the modified Tardieu scale (MTS) in a semi-standing position, used for the assessment of hamstrings spasticity, was better associated with knee extension and hamstrings activity in terminal swing than the MTS in a supine position in children with

Comparison of Organ Location, Morphology, and Rib Coverage of a Midsized Male in the Supine and Seated Positions

Directory of Open Access Journals (Sweden)

Ashley R. Hayes

2013-01-01

Full Text Available The location and morphology of abdominal organs due to postural changes have implications in the prediction of trauma via computational models. The purpose of this study is to use data from a multimodality image set to devise a method for examining changes in organ location, morphology, and rib coverage from the supine to seated postures. Medical images of a male volunteer (78.6±0.77 kg, 175 cm in three modalities (Computed Tomography, Magnetic Resonance Imaging (MRI, and Upright MRI were used. Through image segmentation and registration, an analysis between organs in each posture was conducted. For the organs analyzed (liver, spleen, and kidneys, location was found to vary between postures. Increases in rib coverage from the supine to seated posture were observed for the liver, with a 9.6% increase in a lateral projection and a 4.6% increase in a frontal projection. Rib coverage area was found to increase 11.7% for the spleen. Morphological changes in the organs were also observed. The liver expanded 7.8% cranially and compressed 3.4% and 5.2% in the anterior-posterior and medial-lateral directions, respectively. Similar trends were observed in the spleen and kidneys. These findings indicate that the posture of the subject has implications in computational human body model development.

Human cerebral venous outflow pathway depends on posture and central venous pressure

DEFF Research Database (Denmark)

Gisolf, J; van Lieshout, J J; van Heusden, K

2004-01-01

Internal jugular veins are the major cerebral venous outflow pathway in supine humans. In upright humans the positioning of these veins above heart level causes them to collapse. An alternative cerebral outflow pathway is the vertebral venous plexus. We set out to determine the effect of posture...... and during a Valsalva manoeuvre in both body positions, correlate highly with model simulation of the jugular cross-sectional area (R(2) = 0.97). The results suggest that the cerebral venous flow distribution depends on posture and CVP: in supine humans the internal jugular veins are the primary pathway...

Mechanisms of inhibition of vasopressin release during moderate antiorthostatic posture change in humans

DEFF Research Database (Denmark)

Pump, B.; Gabrielsen, A.; Christensen, N.J.

1999-01-01

The hypothesis was tested that the carotid baroreceptor stimulation caused by a posture change from upright seated with legs horizontal (Seat) to supine (Sup) participates in the suppression of arginine vasopressin (AVP) release. Ten healthy males underwent this posture change for 30 min without...... decreased from 0.9 +/- 0.2 to 0.5 +/- 0.1 pg/ml (P posture...

The influence of body posture on lithium clearance

DEFF Research Database (Denmark)

Kamper, A L; Strandgaard, S; Holstein-Rathlou, N H

1988-01-01

To establish appropriate standard circumstances for lithium clearance measurements, a study was undertaken in 12 healthy volunteers. In each subject, the glomerular filtration rate (GFR), as estimated by [51Cr]EDTA plasma clearance, and the renal clearances of lithium, sodium and potassium were...... during moderate physical activity. Hence, when renal tubular function is studied with the lithium clearance method, standardization of posture and physical activity is important. In such studies physical activity such as walking should particularly be avoided....... measured four times at 1-week intervals: two in the supine and one in the sitting position, and one when the subject was walking around. Glomerular filtration rate was not influenced by posture changes. On the contrary, lithium clearance, which in the supine position was 30 +/- 9 ml/min (1 SD), tended...

The influence of body posture on lithium clearance

DEFF Research Database (Denmark)

Kamper, A L; Strandgaard, S; Holstein-Rathlou, N H

1988-01-01

To establish appropriate standard circumstances for lithium clearance measurements, a study was undertaken in 12 healthy volunteers. In each subject, the glomerular filtration rate (GFR), as estimated by [51Cr]EDTA plasma clearance, and the renal clearances of lithium, sodium and potassium were...... measured four times at 1-week intervals: two in the supine and one in the sitting position, and one when the subject was walking around. Glomerular filtration rate was not influenced by posture changes. On the contrary, lithium clearance, which in the supine position was 30 +/- 9 ml/min (1 SD), tended...... during moderate physical activity. Hence, when renal tubular function is studied with the lithium clearance method, standardization of posture and physical activity is important. In such studies physical activity such as walking should particularly be avoided....

Hand posture effects on handedness recognition as revealed by the Simon effect

Directory of Open Access Journals (Sweden)

Allan P Lameira

2009-11-01

Full Text Available We investigated the influence of hand posture in handedness recognition, while varying the spatial correspondence between stimulus and response in a modified Simon task. Drawings of the left and right hands were displayed either in a back or palm view while participants discriminated stimulus handedness by pressing left/right keys with their hands resting either in a prone or supine posture. As a control, subjects performed a regular Simon task using simple geometric shapes as stimuli. Results showed that when hands were in a prone posture, the spatially corresponding trials (i.e., stimulus and response located on the same side were faster than the non-corresponding trials (i.e., stimulus and response on opposite sides. In contrast, for the supine posture, there was no difference between corresponding and non-corresponding trials. The control experiment with the regular Simon task showed that the posture of the responding hand had no influence on performance. When the stimulus is the drawing of a hand, however, the posture of the responding hand affects the spatial correspondence effect because response location is coded based on multiple reference points, including the body of the hand.

CALF BLOOD-FLOW AND POSTURE - DOPPLER ULTRASOUND MEASUREMENTS DURING AND AFTER EXERCISE

NARCIS (Netherlands)

VANLEEUWEN, BE; BARENDSEN, GJ; LUBBERS, J; DEPATER, L

To investigate the joint effects of body posture and calf muscle pump, the calf blood flow of eight healthy volunteers was measured with pulsed Doppler equipment during and after 3 min of rhythmic exercise on a calf ergometer in the supine, sitting, and standing postures. Muscle contractions

Differential effects of beta-adrenoceptor partial agonists in patients with postural hypotension

DEFF Research Database (Denmark)

Mehlsen, J; Stadeager, C; Trap-Jensen, J

1993-01-01

patients with postural hypotension of different aetiologies. Blood pressure, heart rate and stroke volume were measured in the supine and head-up tilted positions. Left ventricular ejection fraction (LVEF) was measured in the supine position, and vascular resistance, left ventricular volume, and left.......min-1 and LVEF from 0.57 to 0.52, and reduced mean arterial blood pressure from 103 mm Hg to 93 mm Hg. Xamoterol showed beta-adrenoceptor agonistic effects in the supine position through increments in heart rate from 72 to 90 beats.min-1 and LVEF from 0.58 to 0.66, and raised mean arterial blood...... pressure from 108 to 123 mm Hg. It is concluded that the degree of agonist activity of a beta-adrenergic agent is of importance if it is given to a patient with postural hypotension....

Semi-convergence and relaxation parameters for a class of SIRT algorithms

DEFF Research Database (Denmark)

Elfving, Tommy; Nikazad, Touraj; Hansen, Per Christian

2010-01-01

This paper is concerned with the Simultaneous Iterative Reconstruction Technique (SIRT) class of iterative methods for solving inverse problems. Based on a careful analysis of the semi-convergence behavior of these methods, we propose two new techniques to specify the relaxation parameters...

Effects of upright and supine position on cardiac rest and exercise response in aortic regurgitation.

Science.gov (United States)

Shen, W F; Roubin, G S; Fletcher, P J; Choong, C Y; Hutton, B F; Harris, P J; Kelly, D T

1985-02-01

The effects of upright and supine position on cardiac response to exercise were assessed by radionuclide ventriculography in 15 patients with moderate to severe aortic regurgitation (AR) and in 10 control subjects. In patients with AR, heart rate was higher during upright exercise, but systolic and diastolic blood pressure and left ventricular (LV) output were similar during both forms of exercise. LV stroke volume and end-diastolic volume were not altered during supine exercise. LV end-systolic volume increased and ejection fraction decreased during supine exercise, but both were unchanged during upright exercise. Of 15 patients, 5 in the upright and 12 in the supine position had an abnormal LV ejection fraction response to exercise (p less than 0.01). Right ventricular ejection fraction increased and regurgitant index decreased with both forms of exercise and was not significantly different between the 2 positions. Thus, posture is important in determining LV response to exercise in patients with moderate to severe AR.

The Effect of Body Posture on Brain Glymphatic Transport.

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Lee, Hedok; Xie, Lulu; Yu, Mei; Kang, Hongyi; Feng, Tian; Deane, Rashid; Logan, Jean; Nedergaard, Maiken; Benveniste, Helene

2015-08-05

The glymphatic pathway expedites clearance of waste, including soluble amyloid β (Aβ) from the brain. Transport through this pathway is controlled by the brain's arousal level because, during sleep or anesthesia, the brain's interstitial space volume expands (compared with wakefulness), resulting in faster waste removal. Humans, as well as animals, exhibit different body postures during sleep, which may also affect waste removal. Therefore, not only the level of consciousness, but also body posture, might affect CSF-interstitial fluid (ISF) exchange efficiency. We used dynamic-contrast-enhanced MRI and kinetic modeling to quantify CSF-ISF exchange rates in anesthetized rodents' brains in supine, prone, or lateral positions. To validate the MRI data and to assess specifically the influence of body posture on clearance of Aβ, we used fluorescence microscopy and radioactive tracers, respectively. The analysis showed that glymphatic transport was most efficient in the lateral position compared with the supine or prone positions. In the prone position, in which the rat's head was in the most upright position (mimicking posture during the awake state), transport was characterized by "retention" of the tracer, slower clearance, and more CSF efflux along larger caliber cervical vessels. The optical imaging and radiotracer studies confirmed that glymphatic transport and Aβ clearance were superior in the lateral and supine positions. We propose that the most popular sleep posture (lateral) has evolved to optimize waste removal during sleep and that posture must be considered in diagnostic imaging procedures developed in the future to assess CSF-ISF transport in humans. The rodent brain removes waste better during sleep or anesthesia compared with the awake state. Animals exhibit different body posture during the awake and sleep states, which might affect the brain's waste removal efficiency. We investigated the influence of body posture on brainwide transport of inert

Posture and lumbar puncture headache: a controlled trial in 50 patients.

OpenAIRE

Handler, C E; Smith, F R; Perkin, G D; Rose, F C

1982-01-01

A prospective single blind trial in 50 patients was performed to investigate the effect of posture on post lumbar puncture headache (LPH). A difference between the frequency of headache at five hours between the two groups (prone for four hours, versus 30 degrees head down tilt for 30 minutes followed by supine posture for 3 1/2 hours) did not reach significance. These findings do not support the suggestion that a prone posture, by possibly reducing cerebrospinal fluid (CSF) leakage, signific...

Adaptive responses of cardiac function to fetal postural change as gestational age increases

Science.gov (United States)

Kim, Woo Jin; Choi, Hye Jin; Yang, Sun Young; Koo, Boo Hae; Ahn, Ki Hoon; Hong, Soon Cheol; Oh, Min-Jeong; Kim, Hai-Joong

2016-01-01

Objective The cardiovascular system maintains homeostasis through a series of adaptive responses to physiological requirements. However, little is known about the adaptation of fetal cardiac function to gravity, according to gestational age. In the present study, we aimed to evaluate the adaptive responses of cardiac function to postural changes, using Tei index measurements. Methods Fetal echocardiography and Doppler examination were performed on 114 women with vertex singleton pregnancies at 19 to 40 weeks' gestation. Participants were placed in an upright seated position, and the Tei index for fetal left ventricular cardiac function was measured. The women were then moved into a supine position and the Tei index was re-measured. Results The mean Tei index when measured in an upright seated position was significantly lower than that measured in a supine positioning for all fetuses (0.528±0.103 vs. 0.555±0.106, P=0.014, respectively). This difference was also noted in fetuses with a gestational age of 28–40 weeks (0.539±0.107 vs. 0.574±0.102, P=0.011, respectively). However, there was no difference in the Tei index between an upright seated and a supine position among fetuses with a gestational age of Postural changes from an upright seated to a supine position result in an increased Tei index after a gestational age of 28 weeks. This appears to reflect maturation in the adaptive responses of the fetal cardiovascular system to postural changes. PMID:27896244

Effect of the supine position on uterine and umbilical blood flow during the third trimester of uncomplicated pregnancies in multiparous patients.

Science.gov (United States)

Jaffa, A J; Gull, I; Amster, R; Lessing, J B; Wolman, I

2001-01-01

We established the effects of the supine position on umbilical blood flow when measured during the third trimester in 30 multiparous, normotensive patients. Blood flow in the umbilical and uterine arteries and blood pressure in the brachial and popliteal arteries were blindly taken by two different observers: first in the lateral and 5 min later in the supine position. There was a significant difference in mean blood pressure between the two postures. However, there was no statistical difference in the pulse pressure or in systolic/diastolic ratio in the umbilical and uterine arteries between the two positions. Postural changes in normotensive multiparous patients do not affect uterine and umbilical blood flow during the third trimester of uncomplicated pregnancies. Copyright 2001 S. Karger AG, Basel

Natural Body Posture of Preference in the Dying Process : An Explorative Observational Study in a hospicesetting

NARCIS (Netherlands)

Verboeket-Crul, Cathelijne; Thien, Nynke; Teunissen, SCCM

2016-01-01

Background: All people have different postures while sleeping. Most people will prefer a lateral position. In the last days and hours before dying, patients are usually to be found in a supine position. In literature so far it has never been questioned whether the supine position is the most

Acute effects of exercise posture on executive function in transient ischemic attack patients.

Science.gov (United States)

Faulkner, James; Stoner, Lee; Grigg, Rebecca; Fryer, Simon; Stone, Keeron; Lambrick, Danielle

2017-08-01

In patients with stroke or transient ischemic attacks (TIA), a decline in executive function may limit an individual's ability to process motor tasks and relearn motor skills. The purpose of this study was to assess the acute effect of exercise posture (seated vs. supine cycle ergometry) on executive function and prefrontal cortex perfusion in patients with TIA. Eleven TIA patients (65 ± 10 years) and 15 age-matched, healthy controls (HC; 62 ± 7 years) completed two exercise tests to maximal capacity (one seated, one supine) and two 30-min submaximal exercise tests (one seated, one supine). Executive function was assessed prior to and following (1.5 min post, 15 min post) the submaximal exercise tests using a Stroop task. Prefrontal cortex perfusion (total hemoglobin) was continuously recorded using near-infrared spectroscopy. There was no Posture (seated, supine) × Group (TIA, HC) interaction for the Stroop task (p > .05). HC completed Stroop tasks significantly faster than TIA (51.9[SD = 10.3] vs. 64.2[8.5] s, respectively), while Stroop completion time significantly improved between baseline and 1.5 min post (61.3[10] vs. 58.1[9.4] s, respectively) and 1.5 min post and 15 min post (54.8[8.9] s). Posture and group had no significant influence on prefrontal cortex perfusion (p > .05). In summary, executive function improves to a similar extent in TIA and age-matched, healthy controls following an acute bout of exercise, regardless of exercise posture. As acute improvements in executive function were maintained for 15 min, there could be an important window of opportunity for assigning executive tasks following exercise rehabilitation for patients with TIA. © 2017 Society for Psychophysiological Research.

Effect of Semi-Rigid and Soft Ankle Braces on Static and Dynamic Postural Stability in Young Male Adults

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Noriaki Maeda, Yukio Urabe, Shogo Tsutsumi, Shuhei Numano, Miho Morita, Takuya Takeuchi, Shou Iwata, Toshiki Kobayashi

2016-06-01

Full Text Available Ankle braces have been suggested to protect ankle joints from a sprain by restricting inversion and improving proprioception. However, the difference in effects between a semi-rigid brace and a soft brace regarding dynamic postural control after landing is not known. The aim of the present study was to compare the effect of soft (SB and semi-rigid (SRB ankle braces on static and dynamic postural stability in healthy young men. Altogether, 21 male adults (mean age 24.0 ± 1.5 years were assessed for one leg while wearing non-brace (NB, SB or SRB. Balance in single-limb stance on a single-force platform with open eyes and closed eyes were assessed for the non-dominant leg under SB, SRB, and NB conditions. Locus length/second (mm/s and the enveloped area (mm·s-2 surrounded by the circumference of the wave pattern during postural sway were calculated. For assessing dynamic postural stability, the participant jumped and landed on one leg on a force platform, and the Dynamic Postural Stability Index (DPSI and the maximum vertical ground reaction force (vGRFmax were measured. The data were compared among the three conditions with repeated-measures analysis of variance. The correlations between locus length/second, enveloped area, DPSI values (DPSI, Anterior-Posterior Stability Index, Medial-Lateral Stability Index, and Vertical Stability Index, and vGRFmax were then calculated. The results indicated that locus length/second and enveloped area with open eyes and closed eyes were not significantly different for each condition. However, a significant lower in the DPSI and Vertical Stability Index were observed with the SRB in comparison to the SB and NB. A significant improvement in vGRFmax was also observed with the SRB in comparison to NB. SRB demonstrated a positive effect on dynamic postural stability after landing on a single leg and may improve balance by increasing dynamic postural stability.

Dynamic genetic linkage of intermediate blood pressure phenotypes during postural adaptations in a founder population

Science.gov (United States)

Arenas, I. A.; Tremblay, J.; Deslauriers, B.; Sandoval, J.; Šeda, O.; Gaudet, D.; Merlo, E.; Kotchen, T.; Cowley, A. W.

2013-01-01

Blood pressure (BP) is a dynamic phenotype that varies rapidly to adjust to changing environmental conditions. Standing upright is a recent evolutionary trait, and genetic factors that influence postural adaptations may contribute to BP variability. We studied the effect of posture on the genetics of BP and intermediate BP phenotypes. We included 384 sib-pairs in 64 sib-ships from families ascertained by early-onset hypertension and dyslipidemia. Blood pressure, three hemodynamic and seven neuroendocrine intermediate BP phenotypes were measured with subjects lying supine and standing upright. The effect of posture on estimates of heritability and genetic covariance was investigated in full pedigrees. Linkage was conducted on 196 candidate genes by sib-pair analyses, and empirical estimates of significance were obtained. A permutation algorithm was implemented to study the postural effect on linkage. ADRA1A, APO, CAST, CORIN, CRHR1, EDNRB, FGF2, GC, GJA1, KCNB2, MMP3, NPY, NR3C2, PLN, TGFBR2, TNFRSF6, and TRHR showed evidence of linkage with any phenotype in the supine position and not upon standing, whereas AKR1B1, CD36, EDNRA, F5, MMP9, PKD2, PON1, PPARG, PPARGC1A, PRKCA, and RET were specifically linked to standing phenotypes. Genetic profiling was undertaken to show genetic interactions among intermediate BP phenotypes and genes specific to each posture. When investigators perform genetic studies exclusively on a single posture, important genetic components of BP are missed. Supine and standing BPs have distinct genetic signatures. Standardized maneuvers influence the results of genetic investigations into BP, thus reflecting its dynamic regulation. PMID:23269701

Mobility and Balance and Their Correlation with Physiological Factors in Elderly with Different Foot Postures

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Aisyah Mohd Said

2015-01-01

Full Text Available This study determines (1 the correlation between mobility and balance performances with physiological factors and (2 the relationship between foot postures with anthropometric characteristics and lower limb characteristics among elderly with neutral, pronated, and supinated foot. A cross-sectional observational study was conducted in community-dwelling elderly (age: 69.86 ± 5.62 years. Participants were grouped into neutral (n=16, pronated (n=14, and supinated (n=14 foot based on the foot posture index classification. Anthropometric data (height, weight, and BMI, lower limb strength (5-STS and endurance (30 s chair rise test, mobility (TUG, and balance (FSST were determined. Data were analyzed using Spearman’s correlation coefficient. Body weight was negatively and moderately correlated (rs=-0.552, P<0.05 with mobility in supinated foot; moderate-to-high positive linear rank correlation was found between lower limb strength and mobility (rs=0.551 to 0.804, P<0.05 for pronated and neutral foot. Lower limb endurance was negatively and linearly correlated with mobility in pronated (rs=-0.699 and neutral (rs=-0.573 foot. No correlation was observed in balance performance with physiological factors in any of the foot postures. We can conclude that muscle function may be the most important feature to make movement possible in older persons regardless of the type of foot postures.

POSTURAL SHOCK IN PREGNANCY

Science.gov (United States)

Wilkening, Ralph L.; Knauer, John; Larson, Roger K.

1955-01-01

Signs and symptoms of shock may be produced in some patients in late pregnancy by putting them in the dorsal recumbent posture. Change from this position will relieve the condition. The features of the supine hypotensive syndrome can be duplicated by applying pressure to the abdomen with the patient in a lateral position. The postural variations of venous pressure, blood pressure, and pulse appear to be due to obstruction of venous return from the lower portion of the body caused by the large uterus of late pregnancy compressing the vena cava. When shock is observed in a woman in late pregnancy, she should be turned to a lateral position before more active measures of treatment are begun. ImagesFigure 1. PMID:14351983

Foot posture and patellar tendon pain among adult volleyball players.

NARCIS (Netherlands)

Groot, R. de; Malliaras, P.; Munteanu, S.; Payne, C.; Morrissey, D.; Maffulli, N.

2012-01-01

OBJECTIVE: We hypothesized that individuals with a normal foot posture would be less likely to experience patellar tendon pain and pathology than those with a pronated or supinated foot. DESIGN: Observational study. SETTING: Field-based study among competing athletes. PARTICIPANTS: Volleyball

Foot Posture and Patellar Tendon Pain Among Adult Volleyball Players

NARCIS (Netherlands)

de Groot, Reinier; Malliaras, Peter; Munteanu, Shannon; Payne, Craig; Morrissey, Dylan; Maffulli, Nicola

Objective: We hypothesized that individuals with a normal foot posture would be less likely to experience patellar tendon pain and pathology than those with a pronated or supinated foot. Design: Observational study. Setting: Field-based study among competing athletes. Participants: Volleyball

Postural lung recruitment assessed by lung ultrasound in mechanically ventilated children.

Science.gov (United States)

Tusman, Gerardo; Acosta, Cecilia M; Böhm, Stephan H; Waldmann, Andreas D; Ferrando, Carlos; Marquez, Manuel Perez; Sipmann, Fernando Suarez

2017-10-13

Atelectasis is a common finding in mechanically ventilated children with healthy lungs. This lung collapse cannot be overcome using standard levels of positive end-expiratory pressure (PEEP) and thus for only individualized lung recruitment maneuvers lead to satisfactory therapeutic results. In this short communication, we demonstrate by lung ultrasound images (LUS) the effect of a postural recruitment maneuver (P-RM, i.e., a ventilatory strategy aimed at reaerating atelectasis by changing body position under constant ventilation). Data was collected in the operating room of the Hospital Privado de Comunidad, Mar del Plata, Argentina. Three anesthetized children undergoing mechanical ventilation at constant settings were sequentially subjected to the following two maneuvers: (1) PEEP trial in the supine position PEEP was increased to 10 cmH 2 O for 3 min and then decreased to back to baseline. (2) P-RM patient position was changed from supine to the left and then to the right lateral position for 90 s each before returning to supine. The total P-RM procedure took approximately 3 min. LUS in the supine position showed similar atelectasis before and after the PEEP trial. Contrarily, atelectasis disappeared in the non-dependent lung when patients were placed in the lateral positions. Both lungs remained atelectasis free even after returning to the supine position. We provide LUS images that illustrate the concept and effects of postural recruitment in children. This maneuver has the advantage of achieving recruitment effects without the need to elevate airways pressures.

Should Ballet Dancers Vary Postures and Underfoot Surfaces When Practicing Postural Balance?

Science.gov (United States)

Steinberg, Nili; Waddington, Gordon; Adams, Roger; Karin, Janet; Tirosh, Oren

2018-01-01

Postural balance (PB) is an important component skill for professional dancers. However, the effects of different types of postures and different underfoot surfaces on PB have not adequately been addressed. The main aim of this study was to investigate the effect of different conditions of footwear, surfaces, and standing positions on static and dynamic PB ability of young ballet dancers. A total of 36 male and female young professional ballet dancers (aged 14-19 years) completed static and dynamic balance testing, measured by head and lumbar accelerometers, while standing on one leg in the turnout position, under six different conditions: (1) "relaxed" posture; (2) "ballet" posture; (3) barefoot; (4) ballet shoes with textured insoles; (5) barefoot on a textured mat; and (6) barefoot on a spiky mat. A condition effect was found for static and dynamic PB. Static PB was reduced when dancers stood in the ballet posture compared with standing in the relaxed posture and when standing on a textured mat and on a spiky mat (p ballet shoes with textured insoles and when standing on a spiky mat compared with all other conditions (p ballet aligned position, including dance practice on different types of floors and on different types of textured/spiky materials may result in skill transfer to practice on normal floor surfaces, and both static and dynamic PB exercises should be assessed and generalized into practical dance routines.

Effect of Postural Change on Plasma Insulin Concentration in Normal Volunteer

Energy Technology Data Exchange (ETDEWEB)

Sung, Ho Kyung; Koh, Joo Whan; Joo, Jong Koo; Kim, Jin Yong; Lee, Jang Kyu [Korea Atomic Research Institute, Seoul (Korea, Republic of)

1974-03-15

The concentrations of some blood constituents are known to be influenced by the postural change. The blood glucose and insulin concentrations were measured, first, in the supine, and then (30 minutes later) in the erect positions under the fasting state. The effects of a duretic, furose-mide, were also studied under the same condition for 5 consecutive days. The materials were 5 healthy volunteers aging 20-29 years old with out any diabetic past, or family histories. The blood glucose was measured by the Nelson's method, and plasma insulin by the radioimmunoassay method. Following are the results; 1) The plasma insulin concentration in the erect position is slightly higher than in the supine position, however, the increase is statistically insignificant because of the notable individual variations in the values of the supine position. 2) Four out of 5 cases show the increase of about 80% of plasma insulin in the erect position, which is statistically significant if analyzed on the basis of frequency distribution. 3) The blood glucose concentration showed no postural changes. 4) The increase of the plasma insulin concentration in the erect position seems to the result of limited extra vasation of insulin in the lower extremities.

A comparative analysis of the postural and diurnal ocular perfusion pressure of young healthy individuals of different ethnicities

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Alvin J. Munsamy

2018-06-01

Full Text Available Purpose: Ocular perfusion pressure (OPP regulates the flow of blood to the optic nerve and is determined by the interaction between intraocular pressure (IOP and blood pressure (BP. Low OPP increases the incidence of primary open-angle glaucoma (POAG. The aim is to compare the diurnal (i.e. morning vs. afternoon and postural (i.e. seated vs. supine OPP in healthy individuals from different ethnicities aged between 18 and 30 years. Methodology: Averaged IOP and BP measurements were obtained with an ICare rebound tonometer and an automated sphygmomanometer, respectively. Measurements were taken in the morning and afternoon, in the supine and seated positions in healthy young adults: Africans (n = 10, white people (n = 10, mixed-race people (n = 10 and Indians (n = 10. Results: The whole sample (N = 40 displayed a statistically significant reduction in postural and diurnal OPP both in the supine position and in the morning, respectively. A comparative analysis revealed that Africans displayed statistically significant reduction in OPP when compared to other ethnicities. Discussion: A change in posture to the supine position has a greater impact on the reduction of OPP when compared to diurnal changes. Africans displayed clinically significant reduction in OPP which may increase the incidence of POAG in this ethnicity at an early age. Conclusion: Our findings question whether OPP should be considered as a biomarker in the dark-skinned individuals. An evaluation of BP and IOP in the supine position is recommended for all patients to obtain more conclusive readings.

Glaucoma patients demonstrate faulty autoregulation of ocular blood flow during posture change

Science.gov (United States)

Evans, D.; Harris, A.; Garrett, M.; Chung, H. S.; Kagemann, L.

1999-01-01

BACKGROUND/AIMS—Autoregulation of blood flow during posture change is important to ensure consistent organ circulation. The purpose of this study was to compare the change in retrobulbar ocular blood flow in glaucoma patients with normal subjects during supine and upright posture.
METHODS—20 open angle glaucoma patients and 20 normal subjects, similar in age and sex distribution, were evaluated. Blood pressure, intraocular pressure, and retrobulbar blood velocity were tested after 30 minutes of sitting and again after 30 minutes of lying. Retrobulbar haemodynamic measures of peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI) were obtained in the ophthalmic and central retinal arteries using colour Doppler imaging (CDI).
RESULTS—When changing from the upright to supine posture, normal subjects demonstrated a significant increase in OA EDV (p = 0.016) and significant decrease in OA RI (p = 0.0006) and CRA RI (p = 0.016). Glaucoma patients demonstrated similar changes in OA measures of EDV (p = 0.02) and RI (p = 0.04), but no change in CRA measures.
CONCLUSION—Glaucoma patients exhibit faulty autoregulation of central retinal artery blood flow during posture change.

 PMID:10381668

Diuretic treatment in decompensated cirrhosis and congestive heart failure: effect of posture

DEFF Research Database (Denmark)

Ring-Larsen, H; Henriksen, Jens Henrik Sahl; Wilken, C

1986-01-01

The diuretic effect of the supine position was evaluated in six patients with cirrhosis and ascites and six with congestive cardiac failure. After fasting overnight in bed the patients received bumetanide 1 mg intravenously and were then immediately randomly assigned to either bed rest in the sup......The diuretic effect of the supine position was evaluated in six patients with cirrhosis and ascites and six with congestive cardiac failure. After fasting overnight in bed the patients received bumetanide 1 mg intravenously and were then immediately randomly assigned to either bed rest...... in the supine position or normal daily activity in the upright position for the next six hours. Two days later the procedure was repeated, the patients being assigned to the other posture. The diuretic response was similar in patients with heart failure and cirrhosis, and was significantly greater in the supine...

The effect of carotid sinus massage is independent of posture in patients with heart disease

DEFF Research Database (Denmark)

Mickley, H; Hansen, K N; Oxhøj, H

1989-01-01

unilateral right- and left-sided CSM performed in the supine and in the sitting position, while heart rate and systolic blood pressure were monitored. No statistically significant differences in the CSM-induced response in systolic blood pressure or heart rate were found between the two postures....... In the supine position the drop in heart rate was significantly greater after right-sided than after left-sided CSM (P less than 0.05). In only one patient (1%) was a significant carotid sinus reflex evoked. The response was cardioinhibitory with asystole for 3700 ms during right-sided, supine CSM...

Effect of age and posture on human lymphocyte adenylate cyclase activity.

Science.gov (United States)

Mader, S L; Robbins, A S; Rubenstein, L Z; Tuck, M L; Scarpace, P J

1988-03-01

1. A number of age-related changes have been reported in the catecholamine-adrenoceptor-adenylate cyclase system. Most of the data available on these alterations come from resting subjects; the response to acute stress may provide additional insights into the age effect on these responses. 2. We measured supine and 10 min upright plasma noradrenaline and lymphocyte adenylate cyclase activity in ten healthy elderly subjects (age 66-80 years) and seven healthy young subjects (age 27-34 years). 3. Isoprenaline stimulation of lymphocyte adenylate cyclase activity was not significantly different between supine and upright positions or between elderly and young subjects. There was a marked increase in forskolin-stimulated adenylate cyclase activity in the upright posture in both elderly and young subjects. The increment over supine levels was 70% in the elderly (P less than 0.025) and 73% in the young (P less than 0.05). This enhanced forskolin activity was not seen in two young subjects who became syncopal. 4. These data suggest that enhanced forskolin-stimulated adenylate cyclase activity occurs after 10 min of upright posture in both elderly and young subjects, and may be relevant to immediate blood pressure regulation. We were unable to demonstrate any age-related differences in these acute adrenergic responses.

The effect of desmopressin on nocturnal polyuria, overnight weight loss, and morning postural hypotension in patients with autonomic failure.

Science.gov (United States)

Mathias, C J; Fosbraey, P; da Costa, D F; Thornley, A; Bannister, R

1986-01-01

Day and night urine volume, morning and evening body weight, and supine and sitting blood pressure were measured in five patients with chronic autonomic failure who were not receiving treatment with drugs. All had nocturnal polyuria, overnight weight loss, and a pronounced postural fall in blood pressure, with lowest levels in the morning. Desmopressin (2-4 micrograms given intramuscularly at 8 pm) reduced nocturnal polyuria, diminished overnight weight loss, raised supine blood pressure, and reduced the postural fall, especially in the morning, when patients were often at their worst. Desmopressin may be a useful alternative to, or may supplement, other forms of treatment in some patients with autonomic failure. PMID:3089519

Postural effects when cycling in late pregnancy.

Science.gov (United States)

O'Neill, Maureen E; Cooper, Karen A; Boyce, E Stewart; Hunyor, Stephen N

2006-12-01

This study assessed if upright cycling is preferable to semi-recumbent cycling during pregnancy. Healthy women with low risk singleton pregnancies were tested at 34-38 weeks gestation. They cycled for 12 min, either semi-recumbent (45 degrees, n = 27) or upright (n = 23), at 135-145 beats min(-1). When semi-recumbent, minute ventilation was greater (pposture-independent. All increased with exercise (p0.05). Small post-exercise fetal heart rate increases (by 8 beats min(-1), ppostures (n = 11 in each sub-group), with no adverse changes. Fetal heart rate accelerations and uterine activity (n = 11 in each sub-group) were not influenced by posture or exercise. (1) Neither posture had a distinct advantage. (2) Both postures were safe for short duration cycling. (3) The same target maternal heart rates are suitable for both postures because they resulted in similar oxygen consumptions and fetal heart rates.

Effect of change in posture on maternal functional hemodynamics at 35-37 weeks' gestation.

Science.gov (United States)

Guy, G P; Ling, H Z; Machuca, M; Poon, L C; Nicolaides, K H

2018-03-01

To evaluate the effect of posture change from the supine to the sitting position and before and after passive leg raising on maternal functional hemodynamics in pregnant women at 35-37 weeks' gestation, and to compare the changes in pregnancies that subsequently developed pre-eclampsia (PE) or gestational hypertension (GH) with those that remained normotensive. In 2764 singleton pregnancies at 35-37 weeks' gestation, maternal cardiovascular parameters were measured using an automated non-invasive cardiac monitor. The hemodynamic response to a change from the supine to the sitting position and before and after passive leg raising in the left lateral position was examined and compared between women who subsequently developed PE or GH and those who remained normotensive. In normotensive singleton pregnancies at 35-37 weeks' gestation, both change from the supine to the sitting position and passive leg raising were associated with an increase in cardiac index and stroke volume index and a decrease in total peripheral resistance index; there was a small increase in mean arterial pressure with both postural changes and a slight decrease in heart rate with passive leg raising. In pregnancies that subsequently developed PE or GH, compared with normotensive pregnancies, cardiac index and stroke volume index were lower and total peripheral resistance index was higher. In general, change from the supine to the sitting position and passive leg raising were associated with similar but less marked changes in cardiovascular parameters as in normotensive pregnancies. Paradoxically, in late third-trimester normal pregnancy, both change from the supine to a sitting position and passive leg raising may result in an increase in preload with a consequent increase in cardiac and stroke volume indices and a decrease in total peripheral resistance index. In pregnancies that develop PE or GH, the effects of postural change on cardiovascular parameters are similar but less marked than in

Physiological Mechanisms Mediating the Coupling between Heart Period and Arterial Pressure in Response to Postural Changes in Humans.

Science.gov (United States)

Silvani, Alessandro; Calandra-Buonaura, Giovanna; Johnson, Blair D; van Helmond, Noud; Barletta, Giorgio; Cecere, Anna G; Joyner, Michael J; Cortelli, Pietro

2017-01-01

The upright posture strengthens the coupling between heart period (HP) and systolic arterial pressure (SAP) consistently with a greater contribution of the arterial baroreflex to cardiac control, while paradoxically decreasing cardiac baroreflex sensitivity (cBRS). To investigate the physiological mechanisms that mediate the coupling between HP and SAP in response to different postures, we analyzed the cross-correlation functions between low-frequency HP and SAP fluctuations and estimated cBRS with the sequence technique in healthy male subjects during passive head-up tilt test (HUTT, n = 58), during supine wakefulness, supine slow-wave sleep (SWS), and in the seated and active standing positions ( n = 8), and during progressive loss of 1 L blood ( n = 8) to decrease central venous pressure in the supine position. HUTT, SWS, the seated, and the standing positions, but not blood loss, entailed significant increases in the positive correlation between HP and the previous SAP values, which is the expected result of arterial baroreflex control, compared with baseline recordings in the supine position during wakefulness. These increases were mirrored by increases in the low-frequency variability of SAP in each condition but SWS. cBRS decreased significantly during HUTT, in the seated and standing positions, and after blood loss compared with baseline during wakefulness. These decreases were mirrored by decreases in the RMSSD index, which reflects cardiac vagal modulation. These results support the view that the cBRS decrease associated with the upright posture is a byproduct of decreased cardiac vagal modulation, triggered by the arterial baroreflex in response to central hypovolemia. Conversely, the greater baroreflex contribution to cardiac control associated with upright posture may be explained, at least in part, by enhanced fluctuations of SAP, which elicit a more effective entrainment of HP fluctuations by the arterial baroreflex. These SAP fluctuations may result

Relationship between static foot posture and foot mobility

Directory of Open Access Journals (Sweden)

McPoil Thomas G

2011-01-01

Full Text Available Abstract Background It is not uncommon for a person's foot posture and/or mobility to be assessed during a clinical examination. The exact relationship, however, between static posture and mobility is not known. Objective The purpose of this study was to determine the degree of association between static foot posture and mobility. Method The static foot posture and foot mobility of 203 healthy individuals was assessed and then analyzed to determine if low arched or "pronated" feet are more mobile than high arched or "supinated" feet. Results The study demonstrated that those individuals with a lower standing dorsal arch height and/or a wider standing midfoot width had greater mobility in their foot. In addition, those individuals with higher Foot Posture Index (FPI values demonstrated greater mobility and those with lower FPI values demonstrated less mobility. Finally, the amount of foot mobility that an individual has can be predicted reasonably well using either a 3 or 4 variable linear regression model. Conclusions Because of the relationship between static foot posture and mobility, it is recommended that both be assessed as part of a comprehensive evaluation of a individual with foot problems.

Reliability of pulse waveform separation analysis: effects of posture and fasting.

Science.gov (United States)

Stoner, Lee; Credeur, Daniel; Fryer, Simon; Faulkner, James; Lambrick, Danielle; Gibbs, Bethany Barone

2017-03-01

Oscillometric pulse wave analysis devices enable, with relative simplicity and objectivity, the measurement of central hemodynamic parameters. The important parameters are central blood pressures and indices of arterial wave reflection, including wave separation analysis (backward pressure component Pb and reflection magnitude). This study sought to determine whether the measurement precision (between-day reliability) of Pb and reflection magnitude: exceeds the criterion for acceptable reliability; and is affected by posture (supine, seated) and fasting state. Twenty healthy adults (50% female, 27.9 years, 24.2 kg/m) were tested on six different mornings: 3 days fasted, 3 days nonfasted condition. On each occasion, participants were tested in supine and seated postures. Oscillometric pressure waveforms were recorded on the left upper arm. The criterion intra-class correlation coefficient value of 0.75 was exceeded for Pb (0.76) and reflection magnitude (0.77) when participants were assessed under the combined supine-fasted condition. The intra-class correlation coefficient was lowest for Pb in seated-nonfasted condition (0.57), and lowest for reflection magnitude in the seated-fasted condition (0.56). For Pb, the smallest detectible change that must be exceeded in order for a significant change to occur in an individual was 2.5 mmHg, and for reflection magnitude, the smallest detectable change was 8.5%. Assessments of Pb and reflection magnitude are as follows: exceed the criterion for acceptable reliability; and are most reliable when participants are fasted in a supine position. The demonstrated reliability suggests sufficient precision to detect clinically meaningful changes in reflection magnitude and Pb.

Conventional Supine MRI With a Lumbar Pillow-An Alternative to Weight-bearing MRI for Diagnosing Spinal Stenosis?

DEFF Research Database (Denmark)

Hansen, Bjarke Brandt; Hansen, Philip; Grindsted, Jacob

2017-01-01

to conventional MRI were included to an additional positional MRI scan (0.25T G-Scan) performed in: (1) conventional supine, (2) standing, (3) supine with a lumbar pillow in the lower back. LSS was evaluated for each position in consensus on a 0 to 3 semi-quantitative grading scale. Independently, L2-S1 lordosis...... included. The lordosis angle increased significantly from supine to standing (3.2° CI: 1.2-5.2) and with the lumbar pillow (12.8° CI: 10.3-15.3). One-way analysis of variance (ANOVA) showed significant differences between positions (P 

Cardiovascular function in pregnancy: effects of posture.

Science.gov (United States)

Del Bene, R; Barletta, G; Mello, G; Lazzeri, C; Mecacci, F; Parretti, E; Martini, E; Vecchiarino, S; Franchi, F; La Villa, G

2001-04-01

To evaluate the cardiovascular response to active postural changes in pregnancy. Prospective study. Outpatient Clinic, Fetal Maternity Unit. Sixteen healthy women referred prior to pregnancy. Heart rate, arterial pressure, echocardiographic end-diastolic and end-systolic left ventricular volumes (Teichholz' s formula) were measured in the three months before pregnancy, at the end of the first and second trimester, at mid third trimester, and six months after delivery in the supine and standing position, in thirteen women (mean age 33, range 25-38 years). Cardiac output (supine position) significantly increased (28%): it reached its maximum at the second trimester, remained steadily elevated in the mid third trimester, and returned to baseline after delivery. Cardiac output increased during pregnancy also in the active orthostatic position, the percentage increase being greater (70%) since the standing pre-conception value was lower. The postural stress induced similar changes in heart rate, arterial pressure and left ventricular ejection fraction before, during and after pregnancy. However, the reduction in cardiac output associated with early standing attenuated significantly at the second trimester and it was absent at mid third trimester (F = 3.13, P = 0.021). This was due to the interplay between the significantly lesser increase in systemic vascular resistance, occurring since the first trimester, and the significantly lesser decrease in left ventricular end-diastolic volume which was observed in the mid third trimester. These data indicate that the elevated cardiac output is adequately maintained in pregnancy during the postural challenge, due to optimisation of the responses of preload and afterload.

Postural risk assessment of mechanised firewood processing.

Science.gov (United States)

Spinelli, Raffaele; Aminti, Giovanni; De Francesco, Fabio

2017-03-01

The study assessed the postural risk of mechanised firewood processing with eight machines, representing the main technology solutions available on the market. Assessment was conducted with the Ovako Working posture Analysis System (OWAS) on 1000 still frames randomly extracted from videotaped work samples. The postural risk associated with firewood processing was variable and associated with technology type. Simple, manually operated new machines incurred a higher postural risk compared with semi- or fully automatic machines. In contrast, new semi-automatic and automatic machines were generally free from postural risk. In all cases, attention should be paid to postural risk that may occur during blockage resolution. The study did not cover the postural risk of firewood processing sites as a whole. The study provided useful information for selecting firewood processing machinery and for improving firewood machinery design, as part of a more articulate strategy aimed at enhancing the safety of firewood processing work sites. Practitioner Summary: The postural risk associated with mechanised firewood processing (eg cutting and splitting) depends on the type of equipment. Postural risk is highest (OWAS Action Category 2) with new in-line machines, designed for operation by a single worker. Fully automatic machines present minimum postural risk, except during blockage resolution.

Postural effects on intraocular pressure and ocular perfusion pressure in patients with non-arteritic anterior ischemic optic neuropathy.

Science.gov (United States)

Yang, Jee Myung; Park, Sang Woo; Ji, Yong Sok; Kim, Jaeryung; Yoo, Chungkwon; Heo, Hwan

2017-04-20

To investigate postural effects on intraocular pressure (IOP) and ocular perfusion pressure (OPP) in patients with non-arteritic ischemic optic neuropathy (NAION). IOP and blood pressure (BP) were measured in 20 patients with unilateral NAION 10 min after changing to each of the following positions sequentially: sitting, supine, right lateral decubitus position (LDP), supine, left LDP, and supine. IOP was measured using a rebound tonometer and OPP was calculated using formulas based on mean BP. The dependent LDP (DLDP) was defined as the position when the eye of interest (affected or unaffected eye) was placed on the dependent side in the LDP. IOPs were significantly higher (P = 0.020) and OPPs were significantly lower (P = 0.041) in the affected eye compare with the unaffected eye, with the affected eye in DLDP. Compared with the mean IOP of the unaffected eyes, the mean IOP of the affected eyes increased significantly (+2.9 ± 4.4 versus +0.7 ± 3.1 mmHg, respectively; P = 0.003) and the mean OPP decreased significantly (-6.7 ± 9.4 versus -4.9 ± 8.0 mmHg, respectively; P = 0.022) after changing positions from supine to DLDP. In addition, changing position from supine to DLDP showed significantly larger absolute changes in IOP (4.13 ± 3.19 mmHg versus 2.51 ± 1.92 mmHg, respectively; P = 0.004) and OPP (9.86 ± 5.69 mmHg versus 7.50 ± 5.49 mmHg, respectively; P = 0.009) in the affected eye compared with the unaffected eye. In the affected eye, there was a significant positive correlation between absolute change in IOP and OPP when changing position from supine to DLDP (Rho = 0.512, P = 0.021). A postural change from supine to DLDP caused significant fluctuations in IOP and OPP of the affected eye, and may significantly increase IOP and decrease OPP. Posture-induced IOP changes may be a predisposing factor for NAION development.

Thermal sensation during mild hyperthermia is modulated by acute postural change in humans.

Science.gov (United States)

Takeda, Ryosuke; Imai, Daiki; Suzuki, Akina; Ota, Akemi; Naghavi, Nooshin; Yamashina, Yoshihiro; Hirasawa, Yoshikazu; Yokoyama, Hisayo; Miyagawa, Toshiaki; Okazaki, Kazunobu

2016-12-01

Thermal sensation represents the primary stimulus for behavioral and autonomic thermoregulation. We assessed whether the sensation of skin and core temperatures for the driving force of behavioral thermoregulation was modified by postural change from the supine (Sup) to sitting (Sit) during mild hyperthermia. Seventeen healthy young men underwent measurements of noticeable increase and decrease (±0.1 °C/s) of skin temperature (thresholds of warm and cold sensation on the skin, 6.25 cm 2 of area) at the forearm and chest and of the whole-body warm sensation in the Sup and Sit during normothermia (NT; esophageal temperature (T es ), ∼36.6 °C) and mild hyperthermia (HT; T es , ∼37.2 °C; lower legs immersion in 42 °C of water). The threshold for cold sensation on the skin at chest was lower during HT than NT in the Sit (P sensation on the skin at both sites remained unchanged with changes in body posture or temperature. The whole-body warm sensation was higher during HT than NT in both postures and higher in the Sit than Sup during both NT and HT (all, P sensation during mild hyperthermia is modulated by postural change from supine to sitting to sense lesser cold on the skin and more whole-body warmth.

Is there a relationship between preferred posture and positioning in early life and the direction of subsequent asymmetrical postural deformity in non ambulant people with cerebral palsy?

Science.gov (United States)

Porter, David; Michael, Shona; Kirkwood, Craig

2008-09-01

It has been suggested that asymmetrical positioning of an infant with reduced mobility may lead to postural deformity becoming established over time. However, evidence to support or question this line of thinking is lacking. Therefore, the aim of this retrospective cohort study was to test the association between asymmetrical positioning in the first 12 months of life and the subsequent direction of postural deformity in non-ambulant people with cerebral palsy. The direction of scoliosis, pelvic obliquity and windswept hip pattern and also the side of unilateral hip subluxation/dislocation were determined for 246 young people ranging in age from 1 year and 2 months to 19 years (median age 10 years and 3 months). Parents/carers of the participants were interviewed to establish holding and feeding positions and preferred lying posture adopted in early life. Univariate analyses and multivariate logistic regression analyses were carried out. The study provided evidence of an association between asymmetrical lying posture adopted in the first year of life and the direction of the subsequent pattern of postural deformity. If the child's head had been rotated to the right during supine lying, it was more likely that the scoliosis would be convex to the left, pelvic obliquity would be lower on the left, windswept hip pattern would be to the right and hip subluxation/dislocation would occur on the left. The likelihood of the deformities occurring in the same direction was also increased if consistent side lying on the right had been preferred. Clinicians should be aware of positioning for children with severe disabilities particularly those who prefer supine lying with their head rotated to the side and those who prefer consistent side lying.

Regional respiratory clearance of aerosolized /sup 99m/Tc-DTPA: posture and smoking effects

International Nuclear Information System (INIS)

Dusser, D.J.; Minty, B.D.; Collignon, M.A.; Hinge, D.; Barritault, L.G.; Huchon, G.J.

1986-01-01

We studied 10 healthy nonsmokers and 8 healthy smokers, in both the upright and supine position, to investigate whether regional differences in respiratory clearance of technetium-99m-labeled diethylenetriamine pentaacetic acid /sup 99m/Tc-DTPA (RC-DTPA) existed and to assess the influence of posture and smoking on the regional RC-DTPA. RC-DTPA was assessed by the lung clearance rates (%/min) of aerosolized /sup 99m/Tc-DTPA (0.8 micron MMD; 2.4 GSD), using data corrected for recirculating radioactivity, in the upper (zone 1), middle (zone 2), and lower (zone 3) posterior lung fields. In nonsmokers, RC-DTPA in zone 1 was faster than in zone 2 or 3 in both the upright (P less than 0.001) and supine positions (P less than 0.0). No effect was produced by changes in posture on the regional RC-DTPA. In smokers, RC-DTPA was increased in all zones compared with the nonsmokers (P = 0.004), with a further increase in RC-DTP in zone 1 in the upright posture compared with the other regions (P less than 0.001). We conclude that in nonsmokers regional RC-DTPA is faster in zone 1 than in other zones, and this is not related to recirculation of radioactivity; posture does not modify the regional RC-DTPA of nonsmokers; smoking increases RC-DTPA in all zones and more in zone 1 in the upright posture

Body posture recognition and turning recording system for the care of bed bound patients.

Science.gov (United States)

Hsiao, Rong-Shue; Mi, Zhenqiang; Yang, Bo-Ru; Kau, Lih-Jen; Bitew, Mekuanint Agegnehu; Li, Tzu-Yu

2015-01-01

This paper proposes body posture recognition and turning recording system for assisting the care of bed bound patients in nursing homes. The system continuously detects the patient's body posture and records the length of time for each body posture. If the patient remains in the same body posture long enough to develop pressure ulcers, the system notifies caregivers to change the patient's body posture. The objective of recording is to provide the log of body turning for querying of patients' family members. In order to accurately detect patient's body posture, we developed a novel pressure sensing pad which contains force sensing resistor sensors. Based on the proposed pressure sensing pad, we developed a bed posture recognition module which includes a bed posture recognition algorithm. The algorithm is based on fuzzy theory. The body posture recognition algorithm can detect the patient's bed posture whether it is right lateral decubitus, left lateral decubitus, or supine. The detected information of patient's body posture can be then transmitted to the server of healthcare center by the communication module to perform the functions of recording and notification. Experimental results showed that the average posture recognition accuracy for our proposed module is 92%.

The influence of gravity on regional lung blood flow in humans: SPECT in the upright and head-down posture.

Science.gov (United States)

Ax, M; Sanchez-Crespo, A; Lindahl, S G E; Mure, M; Petersson, J

2017-06-01

Previous studies in humans have shown that gravity has little influence on the distribution of lung blood flow while changing posture from supine to prone. This study aimed to evaluate the maximal influence of posture by comparison of regional lung blood flow in the upright and head-down posture in 8 healthy volunteers, using a tilt table. Regional lung blood flow was marked by intravenous injection of macroaggregates of human albumin labeled with 99m Tc or 113m In, in the upright and head-down posture, respectively, during tidal breathing. Both radiotracers remain fixed in the lung after administration. The distribution of radioactivity was mapped using quantitative single photon emission computed tomography (SPECT) corrected for attenuation and scatter. All images were obtained supine during tidal breathing. A shift from upright to the head-down posture caused a clear redistribution of blood flow from basal to apical regions. We conclude that posture plays a role for the distribution of lung blood flow in upright humans, and that the influence of posture, and thereby gravity, is much greater in the upright and head-down posture than in horizontal postures. However, the results of the study demonstrate that lung structure is the main determinant of regional blood flow and gravity is a secondary contributor to the distribution of lung blood flow in the upright and head-down positions. NEW & NOTEWORTHY Using a dual-isotope quantitative SPECT method, we demonstrated that although a shift in posture redistributes blood flow in the direction of gravity, the results are also consistent with lung structure being a greater determinant of regional blood flow than gravity. To our knowledge, this is the first study to use modern imaging methods to quantify the shift in regional lung blood flow in humans at a change between the upright and head-down postures. Copyright © 2017 the American Physiological Society.

Behaviour of motor units of human arm muscles: differences between slow isometric contraction and relaxation

NARCIS (Netherlands)

Denier van der Gon, J.J.; Haar Romenij, ter B.M.; Zuylen, Van E.J.

1985-01-01

The behaviour of motor units in the m. biceps brachii (long head), in the m. brachialis and in the m. supinator during slow isometric contraction and relaxation was studied when subjects were performing different motor tasks. These tasks were: flexion of the elbow joint, supination of the forearm

Human cerebral venous outflow pathway depends on posture and central venous pressure

Science.gov (United States)

Gisolf, J; van Lieshout, J J; van Heusden, K; Pott, F; Stok, W J; Karemaker, J M

2004-01-01

Internal jugular veins are the major cerebral venous outflow pathway in supine humans. In upright humans the positioning of these veins above heart level causes them to collapse. An alternative cerebral outflow pathway is the vertebral venous plexus. We set out to determine the effect of posture and central venous pressure (CVP) on the distribution of cerebral outflow over the internal jugular veins and the vertebral plexus, using a mathematical model. Input to the model was a data set of beat-to-beat cerebral blood flow velocity and CVP measurements in 10 healthy subjects, during baseline rest and a Valsalva manoeuvre in the supine and standing position. The model, consisting of 2 jugular veins, each a chain of 10 units containing nonlinear resistances and capacitors, and a vertebral plexus containing a resistance, showed blood flow mainly through the internal jugular veins in the supine position, but mainly through the vertebral plexus in the upright position. A Valsalva manoeuvre while standing completely re-opened the jugular veins. Results of ultrasound imaging of the right internal jugular vein cross-sectional area at the level of the laryngeal prominence in six healthy subjects, before and during a Valsalva manoeuvre in both body positions, correlate highly with model simulation of the jugular cross-sectional area (R2 = 0.97). The results suggest that the cerebral venous flow distribution depends on posture and CVP: in supine humans the internal jugular veins are the primary pathway. The internal jugular veins are collapsed in the standing position and blood is shunted to an alternative venous pathway, but a marked increase in CVP while standing completely re-opens the jugular veins. PMID:15284348

Nasal obstruction and sleep-disordered breathing: the effect of supine body position on nasal measurements in snorers.

Science.gov (United States)

Virkkula, Paula; Maasilta, Paula; Hytönen, Maija; Salmi, Tapani; Malmberg, Henrik

2003-06-01

Nasal obstruction is considered to be a potential etiological factor in sleep-disordered breathing. However, a significant correlation between nasal measurements and obstructive sleep apnea has not been demonstrated so far. The aim of this study was to investigate the relationships between nasal resistance, nasal volumes and selected sleep parameters using nasal measurements performed in both seated and supine positions. We also investigated whether snoring patients in our clinical sample showed increased positional or decongestive nasal mucosal changes. Forty-one snoring men on a waiting list for correction of nasal obstruction underwent polysomnography, anterior rhinomanometry and acoustic rhinometry. Nineteen non-snoring control subjects were also recruited. Nasal measurements were performed in a seated position, after lying down in a supine position and, after decongestion of nasal mucosa, in a seated position again. In the overall patient group, nasal volume at a distance 2-4 cm from the nares in the supine position correlated inversely with apnea-hypopnea index (AHI) (r = -0.32, p patients, total nasal resistance measured in a supine position correlated with AHI (r = 0.50, p position and sleep parameters. Postural or decongestive changes in nasal measurements were not increased in snoring patients compared with control subjects. The relationship found between nasal measurements and sleep parameters suggests that nasal obstruction does augment airway collapse.

Human cerebral venous outflow pathway depends on posture and central venous pressure

DEFF Research Database (Denmark)

Gisolf, J; van Lieshout, J J; van Heusden, K

2004-01-01

and central venous pressure (CVP) on the distribution of cerebral outflow over the internal jugular veins and the vertebral plexus, using a mathematical model. Input to the model was a data set of beat-to-beat cerebral blood flow velocity and CVP measurements in 10 healthy subjects, during baseline rest......Internal jugular veins are the major cerebral venous outflow pathway in supine humans. In upright humans the positioning of these veins above heart level causes them to collapse. An alternative cerebral outflow pathway is the vertebral venous plexus. We set out to determine the effect of posture...... and a Valsalva manoeuvre in the supine and standing position. The model, consisting of 2 jugular veins, each a chain of 10 units containing nonlinear resistances and capacitors, and a vertebral plexus containing a resistance, showed blood flow mainly through the internal jugular veins in the supine position...

AN INVESTIGATION OF A REFERENCE POSTURE USED IN DETERMINING REARFOOT KINEMATICS FOR BOTH HEALTHY AND PATELLOFEMORAL PAIN SYNDROME INDIVIDUALS

Directory of Open Access Journals (Sweden)

Pazit Levinger

2005-09-01

Full Text Available The choice of a reference posture is important when investigating rearfoot motion in clinical populations. The reference posture used may affect the magnitude of the peak angles and therefore may not enable comparison of the rearfoot kinematics across different populations. This study examined the relationship between the rearfoot frontal plane pattern of motion and three reference postures during the stance phase of walking in healthy and patellofemoral pain syndrome (PFPS subjects. The three reference postures investigated were: Relaxed Standing posture, subtalar joint neutral position (STJN and when the calcaneus and the lower leg were vertically aligned (Vertical Alignment. The rearfoot inversion/eversion during the stance phase was measured in 14 healthy subjects and 13 subjects with diagnosed PFPS using three dimensional motion analysis with the three different reference postures. The graphs of rearfoot inversion/eversion motion were overlaid with the angle at the rearfoot in the static posture and any intersection between the static angle and rearfoot motion was noted. An ANOVA showed significant differences in static posture between the groups for Relaxed Standing (p = 0.01, and STJN (p = 0.02. For both groups, with Relaxed Standing as a reference posture, the mean rearfoot pattern of motion did not intersect the Relaxed Standing static angle during the stance phase. The use of Vertical Alignment reference posture, however, showed an intersection of this reference posture through the rearfoot pattern of motion. The use of the Vertical Alignment reference posture also generated a typical rearfoot motion pattern for both groups and therefore it may be an appropriate reference posture for both healthy and PFPS individuals

Cardiovascular responses to postural changes: differences with age for women and men

Science.gov (United States)

Frey, M. A.; Tomaselli, C. M.; Hoffler, W. G.

1994-01-01

The cardiovascular responses to postural change, and how they are affected by aging, are inadequately described in women. Therefore, the authors examined the influence of age and sex on the responses of blood pressure, cardiac output, heart rate, and other variables to change in posture. Measurements were made after 10 minutes each in the supine, seated, and standing positions in 22 men and 25 women who ranged in age from 21 to 59 years. Several variables differed, both by sex and by age, when subjects were supine. On rising, subjects' diastolic and mean arterial pressures, heart rate, total peripheral resistance (TPR), and thoracic impedance increased; cardiac output, stroke volume, and mean stroke ejection rate decreased; and changes in all variables, except heart rate, were greater from supine to sitting than sitting to standing. The increase in heart rate was greater in the younger subjects, and increases in TPR and thoracic impedance were greater in the older subjects. Stroke volume decreased less, and TPR and thoracic impedance increased more, in the women than in the men. The increase in TPR was particularly pronounced in the older women. These studies show that the cardiovascular responses to standing differ, in some respects, between the sexes and with age. The authors suggest that the sex differences are, in part, related to greater decrease of thoracic blood volume with standing in women than in men, and that the age differences result, in part, from decreased responsiveness of the high-pressure baroreceptor system.

Human Posture Identification Using a MIMO Array

Directory of Open Access Journals (Sweden)

Dai Sasakawa

2018-03-01

Full Text Available The elderly are constantly in danger of falling and injuring themselves without anyone realizing it. A safety-monitoring system based on microwaves can ease these concerns. The authors have proposed safety-monitoring systems that use multiple-input multiple-output (MIMO radar to localize persons by capturing their biological activities such as respiration. However, our studies to date have focused on localization, which is easier to achieve than an estimation of human postures. This paper proposes a human posture identification scheme based on height and a Doppler radar cross section (RCS as estimated by a MIMO array. This scheme allows smart home applications to dispense with contact and wearable devices. Experiments demonstrate that this method can identify the supine position (i.e., after a fall with 100% accuracy, and the average identification rate is 95.0%.

Is There Any Association Between Foot Posture and Lower Limb-Related Injuries in Professional Male Basketball Players? A Cross-Sectional Study.

Science.gov (United States)

Lopezosa-Reca, Eva; Gijon-Nogueron, Gabriel; Morales-Asencio, Jose Miguel; Cervera-Marin, Jose Antonio; Luque-Suarez, Alejandro

2017-12-19

Several studies have shown that foot posture is related to the incidence of ankle sprains in athletes and in nonathletic populations, but this association has not previously been considered in basketball players. This study investigates the relationship between foot posture and lower limb injuries in elite basketball players. Two hundred twenty participants were recruited as a convenience sample. The players had a mean age of 22.51 ± 3.88 years and a body mass index of 23.98 ± 1.80. The players' medical records were accessed from the preceding 10 years, and injuries were recorded according to their location (knee, foot, and/or ankle). In addition, the Foot Posture Index (FPI) was scored for each player, and their playing positions were noted. An average FPI score of 2.66 was obtained across all players, with guards presenting a significantly lower average FPI of -0.48 (P patellar tendinopathy (n = 126). Patellar tendinopathy was more common in supinated feet (30.08%) compared with 20.7% and 19.8% in pronated and neutral feet, respectively. The most common lower limb injuries observed in basketball players were lateral ankle sprain and patellar tendinopathy. Patellar tendinopathy was more commonly associated with the supinated feet. Guard players tended to have a more supinated foot, whereas centers presented a more pronated foot.

The effects of odour and body posture on perceived duration

Directory of Open Access Journals (Sweden)

Eliane eSchreuder

2014-02-01

Full Text Available This study reports an examination of the internal clock model, according to which subjective time duration is influenced by attention and arousal state. In a time production task, we examine the hypothesis that an arousing odour and an upright body posture affect perceived duration.The experimental task was performed while participants were exposed to an odour and either sitting upright (arousing condition or lying down in a relaxing chair (relaxing condition. They were allocated to one of three experimental odour conditions: rosemary (arousing condition, peppermint (relaxing condition and no odour (control condition. The predicted effects of the odours were not borne out by the results. Self-reported arousal and pleasure states were measured before, during (after each body posture condition and post experimentally. Heart rate and skin conductance were measured before and during the experiment. As expected, odour had an effect on perceived duration. When participants were exposed to rosemary odour, they produced significantly shorter time intervals than in the no odour condition. This effect, however, could not be explained by increased arousal. There was no effect of body posture on perceived duration, even though body posture did induce arousal. The results do not support the proposed arousal mechanism of the internal clock model.

Influence on intraocular pressure of the postural change and daily activities in the early morning in suspected glaucoma patients

Directory of Open Access Journals (Sweden)

Ting Chen

2014-05-01

Full Text Available AIM:To evaluate the influence on intraocular pressure(IOPof the postural change and daily activities in the early morning in suspected glaucoma patients.METHODS:The supine and sitting IOP were measured and analyzed on 51 suspected glaucoma patients(100 eyeswith Icare rebound tonometer before and after getting up and daily activities in the early morning. RESULTS: The mean of sitting IOP of 51 patients was 17.12±4.53mmHg, which was significantly lower than the mean of supine IOP(19.14±5.51mmHg. The mean of IOP before and after daily activity of 51 patients were 17.12±4.53mmHg and 14.44±3.90mmHg respectively, which showed significantly difference. CONCLUSION:Postural change and daily activities can result in significant changes of IOP in suspected glaucoma patients.

Sonoanatomical Change of Phrenic Nerve According to Posture During Ultrasound-Guided Stellate Ganglion Block.

Science.gov (United States)

Joeng, Eui Soo; Jeong, Young Cheol; Park, Bum Jun; Kang, Seok; Yang, Seung Nam; Yoon, Joon Shik

2016-04-01

To evaluate the risk of phrenic nerve injury during ultrasound-guided stellate ganglion block (US-SGB) according to sonoanatomy of the phrenic nerve, and determine a safer posture for needle insertion by assessing its relationship with surrounding structure according to positional change. Twenty-nine healthy volunteers were recruited and underwent ultrasound in two postures, i.e., supine position with the neck extension and head rotation, and lateral decubitus position. The transducer was placed at the anterior tubercle of the C6 level to identify phrenic nerve. The cross-sectional area (CSA), depth from skin, distance between phrenic nerve and anterior tubercle of C6 transverse process, and the angle formed by anterior tubercle, posterior tubercle and phrenic nerve were measured. The phrenic nerve was clearly identified in the intermuscular fascia layer between the anterior scalene and sternocleidomastoid muscles. The distance between the phrenic nerve and anterior tubercle was 10.33±3.20 mm with the supine position and 9.20±3.31 mm with the lateral decubitus position, respectively. The mean CSA and skin depth of phrenic nerve were not statistically different between the two positions. The angle with the supine position was 48.37°±27.43°, and 58.89°±30.02° with the lateral decubitus position. The difference of angle between the two positions was statistically significant. Ultrasound is a useful tool for assessing the phrenic nerve and its anatomical relation with other cervical structures. In addition, lateral decubitus position seems to be safer by providing wider angle for needle insertion than the supine position in US-SGB.

Effect of the left lateral recumbent position compared with the supine and upright positions on placental blood flow in normal late pregnancy.

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Suonio, S; Simpanen, A L; Olkkonen, H; Haring, P

1976-02-01

The placental blood flow was assessed by the 99mTc accumulation method in 10 normal pregnancies in the left lateral recumbent position accomplished by a 15 degree wedge and in the supine position. The postural change caused a 17% decrease in the mean placental accumulation rate, which was not statistically significant. Ten patients were moved from the left lateral recumbent position to the upright position, which caused a statistically significant 23% decrease in the mean accumulation rate. Other haemodynamic variables studied were the maternal heart rate and the systolic and diastolic blood pressures. The clinical significance of the haemodynamic changes produced by alterations in posture are briefly discussed.

Age-related differences in norepinephrine kinetics: Effect of posture and sodium-restricted diet

International Nuclear Information System (INIS)

Supiano, M.A.; Linares, O.A.; Smith, M.J.; Halter, J.B.

1990-01-01

We used compartmental analysis to study the influence of age on the kinetics of norepinephrine (NE) distribution and metabolism. Plasma NE and [3H]NE levels were measured in 10 young (age 19-33 yr) and 13 elderly (age 62-73 yr) subjects in the basal supine position, during upright posture, and after 1 wk of a sodium-restricted diet. We found that the basal supine release rate of NE into the extravascular compartment, which is the site of endogenous NE release (NE2), was significantly increased in the elderly group (young, 9.6 +/- 0.5; elderly, 12.3 +/- 0.8 nmol.min-1.m-2; means +/- SE; P = 0.016), providing direct evidence for an age-related increase in sympathetic nervous system (SNS) tone. Although upright posture led to a greater increase in plasma NE in the young (0.90 +/- 0.07 to 2.36 +/- 0.16 nM) than in the elderly (1.31 +/- 0.11 to 2.56 +/- 0.31 nM; age group-posture interaction, P = 0.02), the increase in NE2 was similar between the young (9.6 +/- 0.6 to 16.2 +/- 1.5 nmol.min-1.m-2) and the elderly (11.6 +/- 1.4 to 16.1 +/- 2.4 nmol.min-1.m-2; posture effect, P = 0.001; age group-posture interaction, P = 0.15). Thus the increase in SNS tone resulting from upright posture was similar in young and elderly subjects. Plasma NE levels increased similarly in both groups after a sodium-restricted diet (diet effect, P = 0.001; age group-diet interaction, P = 0.23). However, NE2 did not increase significantly in either group (diet effect, P = 0.26), suggesting that SNS tone did not increase after a sodium-restricted diet. Compartmental analysis provides a description of age-related differences in NE kinetics, including an age-related increase in the extravascular NE release rate

A new approach for assessing sleep duration and postures from ambulatory accelerometry.

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Cornelia Wrzus

Full Text Available Interest in the effects of sleeping behavior on health and performance is continuously increasing-both in research and with the general public. Ecologically valid investigations of this research topic necessitate the measurement of sleep within people's natural living contexts. We present evidence that a new approach for ambulatory accelerometry data offers a convenient, reliable, and valid measurement of both people's sleeping duration and quality in their natural environment. Ninety-two participants (14-83 years wore acceleration sensors on the sternum and right thigh while spending the night in their natural environment and following their normal routine. Physical activity, body posture, and change in body posture during the night were classified using a newly developed classification algorithm based on angular changes of body axes. The duration of supine posture and objective indicators of sleep quality showed convergent validity with self-reports of sleep duration and quality as well as external validity regarding expected age differences. The algorithms for classifying sleep postures and posture changes very reliably distinguished postures with 99.7% accuracy. We conclude that the new algorithm based on body posture classification using ambulatory accelerometry data offers a feasible and ecologically valid approach to monitor sleeping behavior in sizable and heterogeneous samples at home.

3D.03: INFLUENCE OF AORTIC ATHEROSCLEROSIS ON THE PROGNOSTIC VALUE OF POSTURAL BLOOD PRESSURE CHANGES.

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Courand, P Y; Fay, H; Harbaoui, B; Khettab, F; Fauvel, J P; Bricca, G; Milon, H; Lantelme, P

2015-06-01

Orthostatic blood pressure (BP) variations have been related with cardiovascular events in hypertensive patients; they are associated with autonomic and neurohormonal abnormalities. Large vessels damages, i.e. aortic atherosclerosis (ATS), may exaggerate this BP deregulation and thus, amplify its prognostic consequence. This study aimed at investigating the interaction of ATS on the prognostic value of postural BP changes. In a cohort of 958 hypertensive patients with an aortography available (mean age 44 ± 11 years, 61% of men, 26.5% of secondary prevention), BP was measured with a manual sphygmomanometer after 10 minutes of rest in the supine position and in the standing position, one minute after assuming the upright position. Supine and standing SBP were each the average of six measurements. Postural BP change was recalculated as absolute value of the difference between mean supine SBP and mean standing SBP. ATS was assessed by a 2-modality score: absent or mild vs. moderate or severe. All-cause and cardiovascular deaths were assessed after 15 years of follow-up. BP was 182/110 mm Hg, on average. During the follow-up, 167 cardiovascular and 280 all-cause death occurred. As illustrated in the figure, an increased risk of death was observed across tertiles of increasing level of postural BP changes in the presence of moderate or severe ATS but not if ATS was absent or mild. In a multivariable Cox Regression analysis adjusted for major cardiovascular risk factors, postural BP change was statistically associated with all-cause and cardiovascular mortality only in the presence of moderate or severe ATS: tertile 2 vs. 1: 2.19 [1.10-4.39] and 2.02 [0.82-4.96] respectively; tertile 3 vs. 1: 3.21 [1.73-5.94] and 4.65 [2.20-9.80] respectively (P for interaction 0.006 for all-cause mortality and 0.002 for cardiovascular mortality). We did not observe such interaction with ECG left ventricular hypertrophy, history of heart failure and anti-hypertensive treatment

Can Postural Instability Respond to Galvanic Vestibular Stimulation in Patients with Parkinson’s Disease?

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Hiroshi Kataoka

2016-01-01

Full Text Available Objective Galvanic vestibular stimulation (GVS activates the vestibular afferents, and these changes in vestibular input exert a strong influence on the subject’s posture or standing balance. In patients with Parkinson’s disease (PD, vestibular dysfunction might contribute to postural instability and gait disorders. Methods Current intensity was increased to 0.7 mA, and the current was applied to the patients for 20 minutes. To perform a sham stimulation, the current intensity was increased as described and then decreased to 0 mA over the course of 10 seconds. The patient’s status was recorded continuously for 20 minutes with the patient in the supine position. Results Three out of 5 patients diagnosed with PD with postural instability and/or abnormal axial posture showed a reduction in postural instability after GVS. The score for item 12 of the revised Unified Parkinson’s Disease Rating Scale part 3 was decreased in these patients. Conclusions The mechanism of postural instability is complex and not completely understood. In 2 out of the 5 patients, postural instability was not changed in response to GVS. Nonetheless, the GVS-induced change in postural instability for 3 patients in our study suggests that GVS might be a therapeutic option for postural instability.

A Case Report and Review of Postural Orthostatic Tachycardia Syndrome in Pregnancy

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Lide, Brianna; Haeri, Sina

2015-01-01

Purpose - Postural orthostatic tachycardia syndrome (POTS) is a form of orthostatic intolerance characterized by an increased heart rate upon transition from supine to standing, and head-up tilt without orthostatic hypotension. Its etiology is multifactorial, and no clear cause has been identified. Common symptoms include light-headedness, blurred vision, weakness, cognitive difficulties, and fatigue and are often accompanied by palpitations, shortness of breath, syncope, or gastrointestinal ...

Confounding compression: the effects of posture, sizing and garment type on measured interface pressure in sports compression clothing.

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Brophy-Williams, Ned; Driller, Matthew William; Shing, Cecilia Mary; Fell, James William; Halson, Shona Leigh; Halson, Shona Louise

2015-01-01

The purpose of this investigation was to measure the interface pressure exerted by lower body sports compression garments, in order to assess the effect of garment type, size and posture in athletes. Twelve national-level boxers were fitted with sports compression garments (tights and leggings), each in three different sizes (undersized, recommended size and oversized). Interface pressure was assessed across six landmarks on the lower limb (ranging from medial malleolus to upper thigh) as athletes assumed sitting, standing and supine postures. Sports compression leggings exerted a significantly higher mean pressure than sports compression tights (P sports compression garments is significantly affected by garment type, size and posture assumed by the wearer.

Three-dimensional analysis of post-caloric nystagmus caused by postural change.

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Young, Y H; Chiang, C W; Wang, C P

2001-01-01

In order to record caloric nystagmus (CN) using three-dimensional videonystagmography (3D VNG) 14 subjects were placed in the supine position with the head tilted up 30 degrees relative to the earth's horizontal plane. After the primary-phase CN had terminated, the subjects were repositioned from a supine to a sitting position, with the head anteflexed 30 degrees for recording the post-caloric nystagmus (PCN). In addition, 8 of the original subjects were placed in the supine position but with the head turned 40 degrees to the left so that the irrigated (right) ear was oriented upwards. After the primary-phase CN had terminated, the subjects were rotated by 180 degrees so that the irrigated ear was oriented downwards to record PCN. The results indicated that both methods successfully provoked horizontal and vertical CN. For torsional CN, the irrigated ear up/down method produced a higher provocation rate (75%) than the supine/sitting method (50%), but the difference was not significant. Comparing the provocation rate of the PCN for the horizontal component revealed that the two methods do not differ significantly. However, when comparing the provocation rates of PCN for the vertical component, the irrigated ear up/down method showed a higher rate (82%) than the supine/sitting method (18%). Thus using 3D VNG coupled with postural change during caloric testing, the horizontal or vertical components of PCN can be successfully provoked.

Foot posture in basketball players with history of the shin splint

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Saeed Forghany

2013-07-01

Full Text Available Introduction: Shin splint is one of the common injuries in most athletes. Although the relationship between abnormal foot posture and shin splint has been reported previously but, the relation between foot posture and shin splint has not been well documented. The aim of this study was to explore the relationship between foot postures in basketball players and the history of shin splint. Materials and Methods: Thirty Iranian male basketball players who had experience of shin splint during last three months were participated in this study. Foot Posture Index (FPI-6 was used as the measure of foot posture. Talar head palpation, curvature at the lateral malleoli, inversion/eversion of the calcaneus, prominence in the region of the talonavicular joint, congruence of the medial longitudinal arch, abduction /adduction of the forefoot on the rear foot were 6 items which were assessed with FPI in the standing position. Foot posture was defined as ‘normal’, ‘supinated’ or ‘pronated. Data were collected and analyzed by SPSS, version16. Results: Most participants showed abnormal foot posture (%80. Fifty-three percent of subjects had pronated foot (%53 and 10% did hyper-pronation. The foot postures of 17% of participants were in supination. The results of this study did not show a significant difference in foot posture between right and left foot (P > 0.05. Conclusion: abnormal foot posture were common (%80 in basketball players with the history of shin splints. These findings could support this idea that the footwear and orthotic prescription both can prevent and treat basketball players with history of shin splints. Keywords: Foot posture, Shin splints, Basketball

Arm rotated medially with supination – the ARMS variant: description of its surgical correction

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Melcher Sonya E

2009-03-01

Full Text Available Abstract Background Patients who have suffered obstetric brachial plexus injury (OBPI have a high incidence of musculoskeletal complications stemming from the initial nerve injury. The presence of muscle imbalances and contractures leads to typical bony changes affecting the shoulder, including the SHEAR (Scapular Hypoplasia, Elevation and Rotation deformity. The SHEAR deformity commonly occurs in conjunction with Medial Rotation Contracture (MRC of the arm. OBPI also causes muscle imbalances at the level of the forearm, that lead to a fixed supination deformity (SD in a small number of patients. Both MRC and SD will cause severe functional limitations without surgical intervention. Methods Fourteen OBPI patients were diagnosed with MRC of the shoulder and SD of the forearm along with SHEAR deformity during a 16 month study period, with eight patients available to long-term follow-up (age range 2.2 – 18 years. Surgical correction of the MRC was performed as a triangle tilt or humeral osteotomy depending on the age of the child, after which, the patients were treated with a radial osteotomy to correct the fixed supination deformity. Function was assessed using the modified Mallet scale, examination of apparent supination and appearance of the extremity at rest. Results Significant functional improvements were observed in patients with surgical reconstruction. Mallet score increased by an average of 5.2 (p Conclusion The simultaneous presence of two opposing deformities in the same limb will visually offset each other at the level of the wrist and hand, giving the false impression of neutral positioning of the limb. In reality, the neutral-appearing position of the hand indicates a fixed supination posture of the forearm in the face of a medial rotation contracture of the shoulder. Both of these deformities require surgical attention, and the presence of concurrent MRC and SD should be monitored for in OBPI patients.

[Changes in intraocular pressure depending on posture].

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Barac, Ramona; Pop, Monica; Tătaru, C; Gheorghe, A; Bădescu, Silvia; Stanciu, Maria; Burcea, M

2014-01-01

Glaucoma is an important eye disease that, left untreated, causes irreversible blindness by affecting optic nerve threads. Decreasing intraocular pressure and maintaining it at a low level throughout the day is one of the objectives of antiglaucoma therapy. This is a prospective study conducted on a sample of 80 patients who presented at "Emergency Eye Hospital" Bucharest between 1st of December 2013 30th of July 2014. Patients were divided into two groups: 40 patients with glaucoma and 40 patients without glaucoma (control group). THE OBJECTIVE OF THE STUDY: To determine changes in intraocular pressure that may occur depending on body posture and the correlations between changes in intraocular pressure and glaucoma, obesity, hypertension. These IOP changes may be important in the progression of glaucoma regarding that one third of our time is spent on supine position during night. RESULTS AND CONCLUZIONS: IOP varies from sitting down to supine position. IOP increases in supine in most patients (with or without glaucoma) with an average of 1.25 mmHg. The increase among patients with glaucoma is higher (1.67 mmHg) compared to those without glaucoma (0.82 mmHg). In patients with hypertension and glaucoma, IOP increased with 2.62 mmHg. In patients with hypertension and obesity IOP increased with 2.5 mmHg.

Posture Used in fMRI-PET Elicits Reduced Cortical Activity and Altered Hemispheric Asymmetry with Respect to Sitting Position: An EEG Resting State Study

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Chiara Spironelli

2017-12-01

Full Text Available Horizontal body position is a posture typically adopted for sleeping or during brain imaging recording in both neuroscience experiments and diagnostic situations. Recent literature showed how this position and similar ones with head down are associated to reduced plasticity, impaired pain and emotional responses. The present study aimed at further understanding the decrease of cortical activity associated with horizontal body position by measuring high-frequency EEG bands – typically associated with high-level cognitive activation – in a resting state experimental condition. To this end, two groups of 16 female students were randomly assigned to either sitting control (SC or 2-h horizontal Bed Rest condition (hBR while EEG was recorded from 38 scalp recording sites. The hBR group underwent several body transitions, from sitting to supine, and from supine to sitting. Results revealed a clear effect of horizontal posture: the hBR group showed, compared to its baseline and to SC, reduced High-Beta and Gamma EEG band amplitudes throughout the 2-h of hBR condition. In addition, before and after the supine condition, hBR group as well as SC exhibited a greater left vs. right frontal activation in both EEG bands while, on the contrary, the supine position induced a bilateral and reduced activation in hBR participants. The cortical sources significantly more active in SC compared with hBR participants included the left Inferior Frontal Gyrus and left Insula. Results are discussed in relation to the differences among neuroimaging methods (e.g., fMRI, EEG, NIRS, which can be partially explained by posture-induced neural network changes.

Energy metabolism of thoracic surgical patients in the early postoperative period. Effect of posture.

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Brandi, L S; Bertolini, R; Janni, A; Gioia, A; Angeletti, C A

1996-03-01

To determine the effect of elective thoracic surgery on energy metabolism and gas exchange and to evaluate whether the 30-degree sitting position would affect these variables. Prospective, unblinded, controlled study. Surgical ICU in a university hospital. Twenty-two adult patients undergoing elective pulmonary resection. Posture change from supine to 30-degree sitting position. Oxygen consumption (VO2), carbon dioxide production (VCO2), respiratory quotient (RQ), and energy expenditure (EE) were measured by means of computerized indirect calorimetry before and after surgery. Heart rate and respiratory frequency were measured continuously during gas exchange measurement. Blood gases were analyzed with an automated blood gas analyzer. Preoperatively, altering position did not affect energy metabolism, gas exchange, and cardiopulmonary variables. Postoperatively, the measured EE was 116% of the expected value. Mean EE and VO2 values for each position were higher than the preoperative values for the corresponding postures (pMean percent increases in EE, VO2, and VCO2 were significantly lower in the 30-degree sitting position than in the supine position (EE: 7.9+/-2.7% vs 14.4+/-2.3%; pexchange for each position were worse than the preoperative values for the corresponding postures (pMean arterial pressure, heart rate, and respiratory frequency for each position were higher than the preoperative values for the corresponding postures (pmean values of these variables occurred between the two positions postoperatively. The early postoperative period of patients undergoing elective thoracic surgery is characterized by a condition of impaired gas exchange and by a hypermetabolic state. Hypermetabolism can be partly mitigated by assuming the 30-degree sitting position.

Comparison of thorasis kyphosis and postural stiffness between elderly females and males in Tehran elderly recreation association

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Minoo Khalkhali zavieh

2013-01-01

Full Text Available Background and Aim: Hyperkyphosis can lead to reduced respiratory capacity, postural disturbance and increased risk of falling. Despite the evidences about the more postural stiffness and kyphosis in elderly compared with young subjects and despite the known role of sex hormones and menopause in lowering the bone density, there is not any study about the effect of sex on the amount of thoracic kyphosis. The objective of this study is measuring and comparing the amount of spinal thoracic kyphosis and postural stiffness between the old females and males.Methods and Materials: In this descriptive-analytical study, in 36 healthy old subjects (21 female and 15 male the amount of spinal thoracic kyphosis was measured by flexible ruler mounted between the spinous process T12 and C7 during, relaxed and erect postures. The difference of the kyphosis in relaxed and erect posture was used as an index of postural stiffness. The kyphosis and postural stiffness was compared between the females and males.Results: The average amount of kyphosis in relaxed and erect standing didn’t have statistically significant difference between females and males. The subjects in both groups could decrease theirs kyphosis in standing erect position (P=0.0001, but the amount of this decrease (postural stiffness was not different between the females and males. Conclusion: In old women (which aren’t osteoporotic hormonal changes due to menopause didn’t induce a statistically significant difference compared to old men in kyphosis and postural stiffness.Postural stiffness was increased by increasing the BMI that could suggest the BMI as an efficient factor in reducing the mobility of the spine.

Comparison of the Effects of Seated, Supine, and Walking Interset Rest Strategies on Work Rate.

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Ouellette, Kristen A; Brusseau, Timothy A; Davidson, Lance E; Ford, Candus N; Hatfield, Disa L; Shaw, Janet M; Eisenman, Patricia A

2016-12-01

Ouellette, KA, Brusseau, TA, Davidson, LE, Ford, CN, Hatfield, DL, Shaw, JM, and Eisenman, PA. Comparison of the effects of seated, supine, and walking interset rest strategies on work rate. J Strength Cond Res 30(12): 3396-3404, 2016-The idea that an upright posture should be maintained during the interset rest periods of training sessions is pervasive. The primary aim of this study was to determine differences in work rate associated with 3 interset rest strategies. Male and female members of the CrossFit community (male n = 5, female n = 10) were recruited to perform a strenuous training session designed to enhance work capacity that involved both cardiovascular and muscular endurance exercises. The training session was repeated on 3 separate occasions to evaluate 3 interset rest strategies, which included lying supine on the floor, sitting on a flat bench, and walking on a treadmill (0.67 m·s). Work rate was calculated for each training session by summing session joules of work and dividing by the time to complete the training session (joules of work per second). Data were also collected during the interset rest periods (heart rate [HR], respiratory rate [RR], and volume of oxygen consumed) and were used to explain why one rest strategy may positively impact work rate compared with another. Statistical analyses revealed significant differences (p ≤ 0.05) between the passive and active rest strategies, with the passive strategies allowing for improved work rate (supine = 62.77 ± 7.32, seated = 63.66 ± 8.37, and walking = 60.61 ± 6.42 average joules of work per second). Results also suggest that the passive strategies resulted in superior HR, RR, and oxygen consumption recovery. In conclusion, work rate and physiological recovery were enhanced when supine and seated interset rest strategies were used compared with walking interset rest.

The effect of postural changes on plasma renin activity during normal and pathologic pregnancies.

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Brandes, J M; Abramovici, H; Katz, M; Diengott, D; Spindel, A; Kahana, L

1978-11-01

A study of the effect of posture on plasma renin activity (PRA) in the third trimester in 27 gravidas revealed a significantly greater increase in PRA in the supine position, compared to the left lateral. The women were classified into 3 groups: normal pregnancy, preeclampsia, intrauterine fetal death. There was no statistical difference in PRA among the 3 groups. It is assumed that the increase of PRA in the supine position was due mainly to mechanical pressure by the gravid uterus on the great vessels (regardless of whether the fetus was dead or alive) and that effective circulatory volume was thus reduced. However, low PRA in the left lateral position in women with preeclampsia seemed to correlate with more severe disease in these women.

Is there a relationship between foetal position and both preferred lying posture after birth and pattern of subsequent postural deformity in non-ambulant people with cerebral palsy?

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Porter, D; Michael, S; Kirkwood, C

2010-09-01

A pattern of postural deformity was observed in a previous study that included an association between direction of spinal curvature and direction of windsweeping with more windswept deformities occurring to the right and lateral spinal curvatures occurring convex to the left. The direction of this pattern was found to be associated with preferred lying posture in early life. The aim of this study was to test the association between foetal position and both the preferred lying posture after birth, and the direction of subsequent postural deformity in non-ambulant children with cerebral palsy (CP). A retrospective cohort study was carried out involving 60 participants at level five on the gross motor function classification for CP. Foetal position during the last month of pregnancy was taken from antenatal records and parents were interviewed to identify preferred lying posture in the first year of life. At the time of the physical assessment ages ranged from 1 year and 1 month to 19 years with a median age of 13 years and 1 month. Foetal presentation was found to be associated with the preferred lying posture with participants carried in a left occipito-anterior/lateral position more likely to adopt a supine head right lying posture, and vice versa. An association was also observed between the foetal position and asymmetrical postural deformity occurring later in life with participants carried in a left occipito-anterior/lateral presentation more likely to have a convex left spinal curve, a lower left pelvic obliquity, and a windswept hip pattern to the right. Clinicians should be aware of the association between foetal presentation, asymmetrical lying posture, and the direction of subsequent postural deformity for severely disabled children. A hypothesis is described that might help to explain these findings.

Posture with elevated and extended thorax. The influence of the position on some haemodynamic and ventilatory parameters under general anaesthesia.

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Videbaek, F

1980-12-01

The effects of a change in posture from flat supine to supine with elevated and extended thorax have been investigated in 12 healthy patients under general anaesthesia prior to elective surgery on the stomach. The following parameters were measured: pulse rate, mean arterial blood pressure (MABP), central venous pressure (CVP), ventilation pressure, oesophageal pressure, and arterial oxygen and carbon dioxide tensions. Changes were measured as deviations from initial values before the change of position at 4 and 15 min after the change. One patient (8%) had a 31% fall in MABP and a 87% fall in CVP, requiring treatment outside the standard procedure, but acceptable values were obtained by simple means. Eleven patients showed only minor changes: a mean initial rise in pulse rate of 10% and a fall in CVP of 25%, after which the pulse rate returned to the initial level and the CVP remained stable. MABP was unchanged, as were ventilation pressure, oesophageal pressure and gas tensions. On the basis of reports in the literature and findings in this study, it is concluded that otherwise healthy patients tolerate the posture well, the slight risk of haemodynamic complications being outweighed by the surgical advantages. This posture should be used with caution in patients who may be haemodynamically unable to compensate.

Cephalic version by postural management for breech presentation.

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Hofmeyr, G Justus; Kulier, Regina

2012-10-17

Babies with breech presentation (bottom first) are at increased risk of complications during birth, and are often delivered by caesarean section. The chance of breech presentation persisting at the time of delivery, and the risk of caesarean section, can be reduced by external cephalic version (ECV - turning the baby by manual manipulation through the mother's abdomen). It is also possible that maternal posture may influence fetal position. Many postural techniques have been used to promote cephalic version. The objective of this review was to assess the effects of postural management of breech presentation on measures of pregnancy outcome. We evaluated procedures in which the mother rests with her pelvis elevated. These include the knee-chest position, and a supine position with the pelvis elevated with a wedge-shaped cushion. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (22 August 2012). Randomised and quasi-randomised trials comparing postural management with pelvic elevation for breech presentation, with a control group. One or both review authors assessed eligibility and trial quality. We have included six studies involving a total of 417 women. The rates for non-cephalic births, Cesarean section and Apgar scores below 7 at one minute, regardless of whether ECV was attempted or not, were similar between the intervention and control groups (risk ratio (RR) 0.98; 95% confidence interval (CI) 0.84 to 1.15; RR 1.10; 95% CI 0.89 to 1.37; RR 0.88; 95% CI 0.50 to 1.55). There is insufficient evidence from well-controlled trials to support the use of postural management for breech presentation. The numbers of women studied to date remain relatively small. Further research is needed.

Adult phantoms as function of body mass, height and posture by using caucasian anthropomorphic statistics

International Nuclear Information System (INIS)

Kramer, Richard; Cassola, Vagner Ferreira; Lira, Carlos Alberto Brayner de Oliveira; Khoury, Helen Jamil; Milian, Felix Mas

2011-01-01

The CALLDose X 4.0 computer program uses conversion coefficients for the MASH and FASH adult phantoms on the vertical and supine postures, representing the standard man and woman according to ICRP 90 and are called 'basic phantoms'. For improving the representation of real patients in the CALLDose X , this paper developed adults phantoms as function of mass and height by using anthropometric data from nine of them prevailing caucasian countries

Reliability of isometric subtalar pronator and supinator strength testing.

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Hagen, Marco; Lahner, Matthias; Winhuysen, Martin; Maiwald, Christian

2015-01-01

Due to the specific anatomy of the subtalar joint with its oblique axis, isometric pronator and supinator strength is not well documented. The purpose of this study was to determine intra- and between-session reliability of pronator and supinator strength and lower leg muscle activity measurements during maximum voluntary isometric contractions (MVIC). Pronator and supinator peak torques (PT), with and without supplementary visual muscle strength biofeedback (FB), and muscular activities of peroneus longus (PL) and tibialis anterior (TA) were assessed twice 3 days apart by the same examiner in 21 healthy young male adults (mean age: 27.6 years; SD = 3.9). Limits of agreement (LoA) and minimum detectable change (MDC) were evaluated. By applying FB, reliability of both pronator and supinator PT was improved: LoA were reduced from 32% to 26% and from 20% to 18% and MDC from 20% to 15% and from 16% to 12% in supinator and pronator PT, respectively. Learning effects in pronator and supinator PT (p isometric subtalar pronator and supinator strength testing is reliable in healthy subjects. LoA of 18% and 26% have to be exceeded for pronator and supinator PT, respectively, to detect relevant effects in repeated measures.

Electrical stimulation of acupuncture points and blood pressure responses to postural changes: a pilot study.

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Jones, Alice Y M; Kwan, Y L; Leung, Nathan T F; Yu, Rachel P W; Wu, Cindy M Y; Warburton, Darren E R

2011-05-01

Application of transcutaneous electrical stimulation over acupuncture points (Acu-TENS) facilitates heart rate recovery after exercise and restores hemodynamic stability after open heart surgery. The role of Acu-TENS on cardiovascular parameters in response to postural changes has not been reported. To investigate (1) the effect of Acu-TENS on blood pressure responses to -10º head-down postural change and (2) whether such effects were associated with modulation by the autonomic nervous system. Sixteen healthy volunteers, mean age 22.8 (SD, 3.1) years, were subjected to a -10º head-down tilt from the supine position on 3 separate occasions and received in random order the following 3 intervention protocols for 40 minutes before the postural change: Acu-TENS (over bilateral acupuncture points, PC6), sham-TENS (TENS applied to the skin over the patellae), and control (no electrical output from the TENS device applied at PC6). Mean arterial pressure, large artery elasticity index, cardiac output, and heart rate were recorded and compared at different stimulation protocols in the supine and -10º head-down tilt positions. Spectral analysis of heart rate variability was used to determine any modulation by the autonomic nervous system. Change in large artery elasticity index was observed only in the Acu-TENS group (P pressure appeared most stable during Acu-TENS. Autonomic nervous system modulation was not apparent with spectral analysis, irrespective of intervention. Sympathetic activity predominated in all positions. Acu-TENS seems to reduce blood pressure changes with -10º head-down tilt with concomitant changes in arterial vessel tone.

Human posture experiments under water: ways of applying the findings to microgravity

Science.gov (United States)

Dirlich, Thomas

For the design and layout human spacecraft interiors the Neutral Body Posture (NBP) in micro-gravity is of great importance. The NBP has been defined as the stable, replicable and nearly constant posture the body "automatically" assumes when a human relaxes in microgravity. Furthermore the NBP, as published, suggests that there is one standard neutral posture for all individuals. Published experiments from space, parabolic flights and under water on the other hand show strong inter-individual variations of neutral (relaxed) postures. This might originate from the quite small sample sizes of subjects analyzed or the different experiment conditions, e. g. space and under water. Since 2008 a collaborative research project focussing on human postures and motions in microgravity has been ongoing at the Technische Univer-sitüt München (TUM). This collaborative effort is undertaken by the Institute of Astronautics a (LRT) and the Institute of Ergonomics (LfE). Several test campaigns have been conducted in simulated microgravity under water using a specially designed standardized experiment setup. Stereo-metric HD video footage and anthropometric data from over 50 subjects (female and male) has been gathered in over 80 experiments. The video data is analyzed using PCMAN software, developed by the LfE, resulting in a 3D volumetric CAD-based model of each subject and posture. Preliminary and ongoing analysis of the data offer evidence for the existence of intra-individually constant neutral postures, as well as continuously recurring relaxation strate-gies. But as with the data published prior the TUM experiments show quite a large variation of inter-individual postures. These variation might be induced or influenced by the special environmental conditions in the underwater experiment. Thus in present paper ways of stan-dardizing data and applying the findings gathered under water to real microgravity are being discussed. The following influences stemming from the

Isometric elbow extensors strength in supine- and prone-lying positions.

Science.gov (United States)

Abdelzaher, Ibrahim E; Ababneh, Anas F; Alzyoud, Jehad M

2013-01-01

The purpose of this study was to compare isometric strength of elbow extensors measured in supine- and prone-lying positions at elbow flexion angles of 45 and 90 degrees. Twenty-two male subjects under single-blind procedures participated in the study. Each subject participated in both supine-lying and prone-lying measuring protocols. Calibrated cable tensiometer was used to measure isometric strength of the right elbow extensors and a biofeedback electromyography was used to assure no substitution movements from shoulder girdle muscles. The mean values of isometric strength of elbow extensors measured from supine-lying position at elbow flexion angles of 45 and 90 degrees were 11.1  ±  4.2 kg and 13.1  ±  4.6 kg, while those measured from prone-lying position were 9.9  ±  3.6 kg and 12  ±  4.2 kg, respectively. There is statistical significant difference between the isometric strength of elbow extensors measured from supine-lying position at elbow flexion angles of 45 and 90 degrees compared to that measured from prone-lying position (p  isometric strength of elbow extensors since supine-lying starting position is better than prone-lying starting position.

How well tolerated is supine percutaneous nephrolithotomy?

NARCIS (Netherlands)

Baard, Joyce; Kamphuis, Guido M.; Westendarp, Matias; de La Rosette, Jean J. M. C. H.

2014-01-01

Supine percutaneous nephrolithotomy (PCNL) has been described in 1988 and several modifications followed since. Despite claimed benefits, supine PCNL is still neglected by the majority of urologists. Lack of experience and the fear of complications are possible explanations for the resistance to

Measuring postural control during mini-squat posture in men with early knee osteoarthritis.

Science.gov (United States)

Petrella, M; Gramani-Say, K; Serrão, P R M S; Lessi, G C; Barela, J A; Carvalho, R P; Mattiello, S M

2017-04-01

Studies have suggested a compromised postural control in individuals with knee osteoarthritis (OA) evidenced by larger and faster displacement of center of pressure (COP). However, quantification of postural control in the mini-squat posture performed by patients with early knee OA and its relation to muscle strength and self-reported symptoms have not been investigated. The main aim of this cross-sectional, observational, controlled study was to determine whether postural control in the mini-squat posture differs between individuals with early knee OA and a control group (CG) and verify the relation among knee extensor torque (KET) and self-reported physical function, stiffness and pain. Twenty four individuals with knee OA grades I and II (OAG) (mean age: 52.35±5.00) and twenty subjects without knee injuries (CG) (mean age: 51.40±8.07) participated in this study. Participants were assessed in postural control through a force plate (Bertec Mod. USA), which provided information about the anterior-posterior (AP) and medial-lateral (ML) COP displacement during the mini-squat, in isometric, concentric and eccentric knee extensor torque (KET) (90°/s) through an isokinetic dynamometer (BiodexMulti-Joint System3, Biodex Medical Incorporation, New York, NY, USA), and in self-reported symptoms through the WOMAC questionnaire. The main outcomes measured were the AP and ML COP amplitude and velocity of displacement; isometric, concentric, and eccentric KET and self-reported physical function, stiffness and pain. No significant differences were found between groups for postural control (p>0.05). Significant lower eccentric KET (p=0.01) and higher scores for the WOMAC subscales of pain (p=postural instability and the need to include quadriceps muscle strengthening, especially by eccentric contractions. The relationship between the self-reported symptoms and a lower and slower COP displacement suggest that the postural control strategy during tasks with a semi-flexed knee

Effect of body posture on involuntary swallow in healthy volunteers.

Science.gov (United States)

Shiino, Yoshitaka; Sakai, Shogo; Takeishi, Ryosuke; Hayashi, Hirokazu; Watanabe, Masahiro; Tsujimura, Takanori; Magara, Jin; Ito, Kayoko; Tsukada, Tetsu; Inoue, Makoto

2016-03-01

Clinically, reclining posture has been reported to reduce risk of aspiration. However, during involuntary swallow in reclining posture, changes in orofacial and pharyngeal movement before and during pharyngeal swallow should be considered. Further, the mechanisms underlying the effect of body posture on involuntary swallow remain unclear. The aim of the present study was to determine the effect of body posture on activity patterns of the suprahyoid muscles and on patterns of bolus transport during a natural involuntary swallow. Thirteen healthy male adults participated in a water infusion test and a chewing test. In the water infusion test, thickened water was delivered into the pharynx at a very slow rate until the first involuntary swallow was evoked. In the chewing test, subjects were asked to eat 10 g of gruel rice. In both tests, the recording was performed at four body postures between upright and supine positions. Results showed that reclining changed the location of the bolus head at the start of swallow and prolonged onset latency of the swallowing initiation. Muscle burst duration and whiteout time measured by videoendoscopy significantly increased with body reclining and prolongation of the falling time. In the chewing test, reclining changed the location of the bolus head at the start of swallow, and the frequency of bolus residue after the first swallow increased. Duration and area of EMG burst and whiteout time significantly increased with body reclining. These data suggest that body reclining may result in prolongation of pharyngeal swallow during involuntary swallow. Copyright © 2015 Elsevier Inc. All rights reserved.

EFFECT OF POSTURAL DRAINAGE POSITIONS ON VITAL PARAMETERS IN ASYMPTOMATIC HEALTHY INDIVIDUALS

Directory of Open Access Journals (Sweden)

Animesh Hazari

2017-09-01

Full Text Available Background: Postural drainage is used exclusively or in combination with other airway clearance techniques in the management of chronic pulmonary diseases. Postural drainage therapy helps to prevent accumulation of secretions in patients who are at high risk for pulmonary complications. It also helps to remove accumulated secretions from the lungs.The role of body positioning on lung function and the clinical implications of postural drainage has been identified in a variety of settings including intensive care units. There is dearth in literature on effects on postural drainage on vital parameters. Thus the objective of the study was to measure the vital parameters at different postural drainage positions in healthy asymptomatic adults. Methods: Twenty healthy subjects participated in the study. The instruments used in the current study included a Pulse oximeter, Sphygmomanometer, Stethoscope, Postural drainage table.The outcome measures of interest were heart rate, respiratoryrate, oxygen saturation, blood pressure and Borg’s scale of rate of perceived exertion. The changes in the vital signs were recorded at different head down titling position of 0°, 15° & 30° in both supine and prone lying positions Results: Statistical significant difference was found for Systolic Blood Pressure in prone lying at different degrees of tilt (p=0.001 and Diastolic Blood Pressure in prone lying (p=0.000. Conclusion: Postural drainage positioning should be given with caution and under proper monitoring as there is a risk of change in the blood pressure even in asymptomatic elderly population. The monitoring of vital signs should be done during the therapy to decrease the risk of complications.

Using impedance cardiography to assess left ventricular systolic function via postural change in patients with heart failure.

Science.gov (United States)

DeMarzo, Arthur P; Calvin, James E; Kelly, Russell F; Stamos, Thomas D

2005-01-01

For the diagnosis and management of heart failure, it would be useful to have a simple point-of-care test for assessing ventricular function that could be performed by a nurse. An impedance cardiography (ICG) parameter called systolic amplitude (SA) can serve as an indicator of left ventricular systolic function (LVSF). This study tested the hypothesis that patients with normal LVSF should have a significant increase in SA in response to an increase in end-diastolic volume caused by postural change from sitting upright to supine, while patients with depressed LVSF associated with heart failure should have a minimal increase or a decrease in SA from upright to supine. ICG data were obtained in 12 patients without heart disease and with normal LVSF and 18 patients with clinically diagnosed heart failure. Consistent with the hypothesis, patients with normal LVSF had a significant increase in SA from upright to supine, whereas heart failure patients had a minimal increase or a decrease in SA from upright to supine. This ICG procedure may be useful for monitoring the trend of patient response to titration of beta blockers and other medications. ICG potentially could be used to detect worsening LVSF and provide a means of measurement for adjusting treatment.

Transient influence of end-tidal carbon dioxide tension on the postural restraint in cerebral perfusion

DEFF Research Database (Denmark)

Immink, R.V.; Truijen, J.; Secher, Niels H.

2009-01-01

In the upright position, cerebral blood flow is reduced, maybe because arterial carbon dioxide partial pressure (Pa(CO(2))) decreases. We evaluated the time-dependent influence of a reduction in Pa(CO(2)), as indicated by the end-tidal Pco(2) tension (Pet(CO(2))), on cerebral perfusion during head......-up tilt. Mean arterial pressure, cardiac output, middle cerebral artery mean flow velocity (MCA V(mean)), and dynamic cerebral autoregulation at supine rest and 70 degrees head-up tilt were determined during free breathing and with Pet(CO(2)) clamped to the supine level. The postural changes in central...... hemodynamic variables were equivalent, and the cerebrovascular autoregulatory capacity was not significantly affected by tilt or by clamping Pet(CO(2)). In the first minute of tilt, the decline in MCA V(mean) (10 +/- 4 vs. 3 +/- 4 cm/s; mean +/- SE; P

Aortic atherosclerosis is a key modulator of the prognostic value of postural blood pressure changes.

Science.gov (United States)

Courand, Pierre-Yves; Harbaoui, Brahim; Fay, Helène; Grandjean, Adrien; Milon, Hugues; Lantelme, Pierre

2018-01-01

Orthostatic blood pressure decrease or increase has been related to cardiovascular events in hypertensive patients. Large blood pressure changes after orthostatic stress are associated with autonomic and neurohormonal abnormalities; aortic atherosclerosis (ATS) may also play a role. We investigated the interaction of ATS on the prognostic value of postural blood pressure changes. In a cohort of 958 hypertensive patients with an aortography (mean ± standard deviation age 44 ± 11 years, 61% men, mean blood pressure 182/110 mmHg), blood pressure was measured after 10 min of rest in the supine position. Systolic blood pressure (SBP) was also measured in standing position, 1 min after the supine position. Blood pressure changes were calculated as supine SBP minus standing SBP and analyzed as absolute or arithmetic means. ATS was assessed using an aortography score. After 15 years of follow-up, 280 all-cause and 167 cardiovascular deaths occurred. In a multivariable Cox regression analysis adjusted for major cardiovascular risk factors and stratified according to ATS status, SBP changes were statistically associated with all-cause and cardiovascular mortality only in the presence of ATS: tertile 3 versus 1, 2.99 (1.37-6.49) and 4.08 (1.55-10.72) respectively, tertile 3 versus 2, 2.89 (1.29-6.46) and 4.82 (1.79-12.98), respectively (p for interaction: 0.003 for all-cause and 0.003 for cardiovascular mortality) for absolute changes. The hazard associated with the magnitude of SBP changes was more important than that associated with its direction. The prognostic significance of postural SBP changes is markedly influenced by ATS in hypertensive patients. Copyright © 2017 Elsevier B.V. All rights reserved.

Xamoterol, a new selective beta-1-adrenoceptor partial agonist, in the treatment of postural hypotension

DEFF Research Database (Denmark)

Mehlsen, J; Trap-Jensen, J

1986-01-01

Three patients severely disabled from postural hypotension were treated with xamoterol, a selective beta-1-adrenoceptor antagonist with a high degree of partial agonist activity. Oral treatment (200 mg b.i.d.) was chosen on the basis of the effects of acute intravenous administration of xamoterol...... and pindolol, a non-selective beta-adrenoceptor antagonist with partial agonist activity. In these patients pindolol had a predominantly antagonist effect, whereas xamoterol had a predominantly agonist effect after intravenous administration. Oral treatment was carried out with placebo control in a single......, supine). During the placebo period (2 weeks) heart rate decreased to pretreatment levels and mean blood pressure was reduced by only 14 mmHg. The patients reported substantial improvement in their condition during active medication. Xamoterol seems to be a useful alternative in the treatment of postural...

Total and regional deposition of inhaled aerosols in supine healthy subjects and subjects with mild-to-moderate COPD

Energy Technology Data Exchange (ETDEWEB)

Darquenne, Chantal; Lamm, Wayne J.; Fine, Janelle M.; Corley, Richard A.; Glenny, Robb W.

2016-09-01

Despite substantial development of sophisticated subject-specific computational models of aerosol transport and deposition in human lungs, experimental validation of predic- tions from these new models is sparse. We collected aerosol retention and exhalation profiles in seven healthy volunteers and six subjects with mild-to-moderate COPD (FEV1 ¼ 50–80%predicted) in the supine posture. Total deposition was measured during continuous breathing of 1 and 2.9 mm-diameter particles (tidal volume of 1 L, flow rate of 0.3 L/s and 0.75 L/s). Bolus inhalations of 1 mm particles were performed to penetration volumes of 200, 500 and 800 mL (flow rate of 0.5 L/s). Aerosol bolus dispersion (H), deposition, and mode shift (MS) were calculated from these data. There was no significant difference in total deposition between healthy subjects and those with COPD. Total deposition increased with increasing particle size and also with increasing flow rate. Similarly, there was no significant difference in aerosol bolus deposition between subject groups. Yet, the rate of increase in dispersion and of decrease in MS with increasing penetration volume was higher in subjects with COPD than in healthy volunteers (H: 0.79870.205 vs. 0.52770.122 mL/mL, p¼ 0.01; MS: - 0.27170.129 vs. - 0.145 70.076 mL/mL, p¼ 0.05) indicating larger ventilation inhomogeneities (based on H) and increased flow sequencing (based on MS) in the COPD than in the healthy group. In conclusion, in the supine posture, deposition appears to lack sensitivity for assessing the effect of lung morphology and/or ventilation distribution alteration induced by mild-to- moderate lung disease on the fate of inhaled aerosols. However, other parameters such as aerosol bolus dispersion and mode shift may be more sensitive parameters for evaluating models of lungs with moderate disease.

Effect of postural changes on aldosterone to plasma renin ratio in patients with suspected secondary hypertension.

Science.gov (United States)

Barigou, M; Ah-Kang, F; Orloff, E; Amar, J; Chamontin, B; Bouhanick, B

2015-06-01

To study the influence of postural changes on aldosterone to renin ratio (ARR) in patients with suspected secondary hypertension and to evaluate the sensitivity and specificity of the recommended seated ARR compared to supine and upright ARR for primary aldosteronism screening. Fifty-three hypertensive patients were prospectively hospitalized for secondary hypertension exploration (age: 51 ± 12, 66% males). After withdrawal of drugs interfering with renin angiotensin system, plasma aldosterone and direct renin concentration were measured in the morning, at bed after an overnight supine position, then out of bed after 1 hour of upright position and finally 2 hours later after 15 minutes of seating. Minimal renin value was set at 5 μUI/mL. Referring to ARR cut-off of 23 pg/μUI, the sensitivity of seated ARR was 57.1% and specificity was 92.3%. The negative and positive predictive values were 95.1% and 45.2% respectively. Compared to these results, a cut-off of 19 improved sensitivity to 85.7% with a specificity of 89.7%. Negative and positive predictive values were 98.3% and 41.1% respectively. Seated ARR mean value was lower than supine and upright ARR mean values, due to an overall increase in renin at seating compared to the supine position by factor 1.9 while aldosterone just slightly increased by factor 1.2. Seated ARR correlated to supine and upright ARR: correlation coefficients (r) 0.90 and 0.93 respectively (P<0.001). Current recommended measurement of ARR in the seating position is fairly correlated to supine and upright ARR. A suggested cut-off value of 19 instead of 23 pg/μUI increased the discriminating power of this test. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Strain modulations as a mechanism to reduce stress relaxation in laryngeal tissues.

Science.gov (United States)

Hunter, Eric J; Siegmund, Thomas; Chan, Roger W

2014-01-01

Vocal fold tissues in animal and human species undergo deformation processes at several types of loading rates: a slow strain involved in vocal fold posturing (on the order of 1 Hz or so), cyclic and faster posturing often found in speech tasks or vocal embellishment (1-10 Hz), and shear strain associated with vocal fold vibration during phonation (100 Hz and higher). Relevant to these deformation patterns are the viscous properties of laryngeal tissues, which exhibit non-linear stress relaxation and recovery. In the current study, a large strain time-dependent constitutive model of human vocal fold tissue is used to investigate effects of phonatory posturing cyclic strain in the range of 1 Hz to 10 Hz. Tissue data for two subjects are considered and used to contrast the potential effects of age. Results suggest that modulation frequency and extent (amplitude), as well as the amount of vocal fold overall strain, all affect the change in stress relaxation with modulation added. Generally, the vocal fold cover reduces the rate of relaxation while the opposite is true for the vocal ligament. Further, higher modulation frequencies appear to reduce the rate of relaxation, primarily affecting the ligament. The potential benefits of cyclic strain, often found in vibrato (around 5 Hz modulation) and intonational inflection, are discussed in terms of vocal effort and vocal pitch maintenance. Additionally, elderly tissue appears to not exhibit these benefits to modulation. The exacerbating effect such modulations may have on certain voice disorders, such as muscle tension dysphonia, are explored.

Strain modulations as a mechanism to reduce stress relaxation in laryngeal tissues.

Directory of Open Access Journals (Sweden)

Eric J Hunter

Full Text Available Vocal fold tissues in animal and human species undergo deformation processes at several types of loading rates: a slow strain involved in vocal fold posturing (on the order of 1 Hz or so, cyclic and faster posturing often found in speech tasks or vocal embellishment (1-10 Hz, and shear strain associated with vocal fold vibration during phonation (100 Hz and higher. Relevant to these deformation patterns are the viscous properties of laryngeal tissues, which exhibit non-linear stress relaxation and recovery. In the current study, a large strain time-dependent constitutive model of human vocal fold tissue is used to investigate effects of phonatory posturing cyclic strain in the range of 1 Hz to 10 Hz. Tissue data for two subjects are considered and used to contrast the potential effects of age. Results suggest that modulation frequency and extent (amplitude, as well as the amount of vocal fold overall strain, all affect the change in stress relaxation with modulation added. Generally, the vocal fold cover reduces the rate of relaxation while the opposite is true for the vocal ligament. Further, higher modulation frequencies appear to reduce the rate of relaxation, primarily affecting the ligament. The potential benefits of cyclic strain, often found in vibrato (around 5 Hz modulation and intonational inflection, are discussed in terms of vocal effort and vocal pitch maintenance. Additionally, elderly tissue appears to not exhibit these benefits to modulation. The exacerbating effect such modulations may have on certain voice disorders, such as muscle tension dysphonia, are explored.

Thermal sensation during mild hyperthermia is modulated by acute postural change in humans

Science.gov (United States)

Takeda, Ryosuke; Imai, Daiki; Suzuki, Akina; Ota, Akemi; Naghavi, Nooshin; Yamashina, Yoshihiro; Hirasawa, Yoshikazu; Yokoyama, Hisayo; Miyagawa, Toshiaki; Okazaki, Kazunobu

2016-12-01

Thermal sensation represents the primary stimulus for behavioral and autonomic thermoregulation. We assessed whether the sensation of skin and core temperatures for the driving force of behavioral thermoregulation was modified by postural change from the supine (Sup) to sitting (Sit) during mild hyperthermia. Seventeen healthy young men underwent measurements of noticeable increase and decrease (±0.1 °C/s) of skin temperature (thresholds of warm and cold sensation on the skin, 6.25 cm2 of area) at the forearm and chest and of the whole-body warm sensation in the Sup and Sit during normothermia (NT; esophageal temperature (Tes), ˜36.6 °C) and mild hyperthermia (HT; Tes, ˜37.2 °C; lower legs immersion in 42 °C of water). The threshold for cold sensation on the skin at chest was lower during HT than NT in the Sit ( P body posture or temperature. The whole-body warm sensation was higher during HT than NT in both postures and higher in the Sit than Sup during both NT and HT (all, P cold on the skin and more whole-body warmth.

Modification of male adult simulator posture of ICRP 110 reference

International Nuclear Information System (INIS)

Galeano, Diego C.; Souza, Divanizia N.; Santos, Willian S.; Carvalho Junior, Alberico B.

2014-01-01

Voxel simulators are usually constructed based on computed tomography and magnetic resonance, so the supine position (lying) is the most used. This may result in a overestimated or underestimated the radiation dose, depending on the exposure scenario adopted. Thus, the objective was to change the attitude of the male adult simulator reference ICRP 110, AM (Adult Male), to a sitting posture. For change of posture were possible, it was necessary increasing the number of slices that comprise AM simulator by reducing the height of the voxel of 8.0 mm to 2.0 mm, thus making each voxel approximately cubic. A subroutine was created in Visual Monte Carlo software (VMC) to rotate the thigh region of the simulator and position it between the region of the leg and trunk. The ScionImage software was used to rebuild and soften the contours of the knee and hip of the simulator in a sitting posture, and 3D visualization of the simulator was used VolView software. The AM simulator in the seated position has the same anatomical features of the simulator in the standing posture. Using the MCNPX code [ref] was carried out the conversion coefficients for calculating the AP irradiation geometry (anteroposterior) comparing the AM simulator standing and sitting in order to evaluate the difference scattering and absorption of radiation by the two simulators. The result shows a difference up to 100% in the fluency conversion coefficients in nearby organs located in the pelvic region and in organs with distribution in the whole body (such as skin, muscle, lymph nodes and skeletal)

A functional MRI Exploration of Hamstring Activation During the Supine Bridge Exercise.

Science.gov (United States)

Bourne, Matthew; Williams, Morgan; Pizzari, Tania; Shield, Anthony

2018-02-01

The single leg supine bridge (SLB) is a commonly employed strengthening exercise and is used as a clinical test for hamstring function in sports, however, little is known about the patterns of muscle activation in this task. To explore these activation patterns, nine healthy, recreationally active males underwent functional magnetic resonance imaging (fMRI) of their thighs at rest and immediately after 5 sets of 10 repetitions of the SLB exercise. Exercise-induced increases in the transverse (T2) relaxation time of the biceps femoris long and short heads, semitendinosus and semimembranosus, were determined via signal intensity changes in pre- and post-exercise images and used as an index of muscle activation. The Bonferroni adjusted alpha was set at phamstring injury prevention and rehabilitation programs. © Georg Thieme Verlag KG Stuttgart · New York.

Effect of the Stroop test performed in supine position on the heart rate variability in both genders.

Science.gov (United States)

Vazan, Rastislav; Filcikova, Diana; Mravec, Boris

2017-12-01

The effect of Stroop test (ST)-induced stress on autonomic nervous system activity is often examined via measurement of heart rate variability (HRV). However, HRV may be significantly affected by interfering factors, including vocalization and inappropriate body position. Surprisingly, published studies ignore these issues, so the aim of our study was to test the innovative procedure for correct HRV measurement in individuals exposed to ST. Moreover, we examined possible gender differences in HRV and heart rate (HR) during ST. Healthy participants (21 men, 34 women) were placed in a supine position (no orthostatic activation) and then exposed to a 5 min relaxation period and a 5 min period of computerized ST (no vocalization). We found significant differences in HR and HRV parameters in both genders during ST when compared to relaxation (baseline) values. On the other hand, there were no significant differences in HR and HRV between males and females (except for a higher baseline HR in women). Also, reactivity to ST stress (difference between baseline and ST value) showed no gender differences. In conclusion, when performed in a supine position and without vocalization, the ST induces significant stress-related changes of HR and HRV in both genders, with no gender differences in the magnitude of reaction to ST stress. This experimental procedure can be used for correct examination of mental stress-related changes in the autonomic nervous system, and is particularly useful for examining mixed-gender experimental groups. Copyright © 2017 Elsevier B.V. All rights reserved.

Thoracic posture, shoulder muscle activation patterns and isokinetic ...

African Journals Online (AJOL)

Background. Shoulder injuries are the most severe injuries in rugby union players, accounting for almost 20% of injuries related to the sport and resulting in lost playing hours. Objective. To profile the thoracic posture, scapular muscle activation patterns and rotator cuff muscle isokinetic strength of semi-professional

A review of postural orthostatic tachycardia syndrome.

LENUS (Irish Health Repository)

Carew, Sheila

2012-01-31

A 21-year-old female reports an 18-month history of light-headedness on standing. This is often associated with palpitations and a feeling of intense anxiety. She has had two black-outs in the past 12 months. She is not taking any regular medications. Her supine blood pressure was 126\\/84 mmHg with a heart rate of 76 bpm, and her upright blood pressure was 122\\/80 mmHg with a heart rate of 114 bpm. A full system examination was otherwise normal. She had a 12-lead electrocardiogram performed which was unremarkable. She was referred for head-up tilt testing. She was symptomatic during the test and lost consciousness at 16 min. Figure 1 summarizes her blood pressure and heart rate response to tilting. A diagnosis of postural orthostatic tachycardia syndrome with overlapping vasovagal syncope was made.

Determining suitable dimensions for dairy goat feeding places by evaluating body posture and feeding reach.

Science.gov (United States)

Keil, Nina M; Pommereau, Marc; Patt, Antonia; Wechsler, Beat; Gygax, Lorenz

2017-02-01

Confined goats spend a substantial part of the day feeding. A poorly designed feeding place increases the risk of feeding in nonphysiological body postures, and even injury. Scientifically validated information on suitable dimensions of feeding places for loose-housed goats is almost absent from the literature. The aim of the present study was, therefore, to determine feeding place dimensions that would allow goats to feed in a species-appropriate, relaxed body posture. A total of 27 goats with a height at the withers of 62 to 80 cm were included in the study. Goats were tested individually in an experimental feeding stall that allowed the height difference between the feed table, the standing area of the forelegs, and a feeding area step (difference in height between forelegs and hind legs) to be varied. The goats accessed the feed table via a palisade feeding barrier. The feed table was equipped with recesses at varying distances to the feeding barrier (5-55 cm in 5-cm steps) at angles of 30°, 60°, 90°, 120°, or 150° (feeding angle), which were filled with the goats' preferred food. In 18 trials, balanced for order across animals, each animal underwent all possible combinations of feeding area step (3 levels: 0, 10, and 20 cm) and of difference in height between feed table and standing area of forelegs (6 levels: 0, 5, 10, 15, 20, and 25 cm). The minimum and maximum reach at which the animals could reach feed on the table with a relaxed body posture was determined for each combination. Statistical analysis was performed using mixed-effects models. The animals were able to feed with a relaxed posture when the feed table was at least 10 cm higher than the standing height of the goats' forelegs. Larger goats achieved smaller minimum reaches and minimum reach increased if the goats' head and neck were angled. Maximum reach increased with increasing height at withers and height of the feed table. The presence of a feeding area step had no influence on minimum and

Quantitative cardiovascular magnetic resonance in pregnant women: cross-sectional analysis of physiological parameters throughout pregnancy and the impact of the supine position.

Science.gov (United States)

Rossi, Alexia; Cornette, Jerome; Johnson, Mark R; Karamermer, Yusuf; Springeling, Tirza; Opic, Petra; Moelker, Adriaan; Krestin, Gabriel P; Steegers, Eric; Roos-Hesselink, Jolien; van Geuns, Robert-Jan M

2011-06-27

There are physiological reasons for the effects of positioning on hemodynamic variables and cardiac dimensions related to altered intra-abdominal and intra-thoracic pressures. This problem is especially evident in pregnant women due to the additional aorto-caval compression by the enlarged uterus. The purpose of this study was to investigate the effect of postural changes on cardiac dimensions and function during mid and late pregnancy using cardiovascular magnetic resonance (CMR). Healthy non-pregnant women, pregnant women at 20th week of gestation and at 32nd week of gestation without history of cardiac disease were recruited to the study and underwent CMR in supine and left lateral positions. Cardiac hemodynamic parameters and dimensions were measured and compared between both positions. Five non-pregnant women, 6 healthy pregnant women at mid pregnancy and 8 healthy pregnant women at late pregnancy were enrolled in the study. In the group of non-pregnant women left ventricular (LV) cardiac output (CO) significantly decreased by 9% (p=0.043) and right ventricular (RV) end-diastolic volume (EDV) significantly increased by 5% (p=0.043) from the supine to the left lateral position. During mid pregnancy LV ejection fraction (EF), stroke volume (SV), left atrium lateral diameter and left atrial supero-inferior diameter increased significantly from the supine position to the left lateral position: 8%, 27%, 5% and 11%, respectively (ppregnancy a significant increment of LV EF, EDV, SV and CO was observed in the left lateral position: 11%, 21%, 35% and 24% (ppregnancy positional changes affect significantly cardiac hemodynamic parameters and dimensions. Pregnant women who need serial studies by CMR should be imaged in a consistent position. From as early as 20 weeks the left lateral position should be preferred on the supine position because it positively affects venous return, SV and CO.

Quantitative cardiovascular magnetic resonance in pregnant women: cross-sectional analysis of physiological parameters throughout pregnancy and the impact of the supine position

Directory of Open Access Journals (Sweden)

Moelker Adriaan

2011-06-01

Full Text Available Abstract Background There are physiological reasons for the effects of positioning on hemodynamic variables and cardiac dimensions related to altered intra-abdominal and intra-thoracic pressures. This problem is especially evident in pregnant women due to the additional aorto-caval compression by the enlarged uterus. The purpose of this study was to investigate the effect of postural changes on cardiac dimensions and function during mid and late pregnancy using cardiovascular magnetic resonance (CMR. Methods Healthy non-pregnant women, pregnant women at 20th week of gestation and at 32nd week of gestation without history of cardiac disease were recruited to the study and underwent CMR in supine and left lateral positions. Cardiac hemodynamic parameters and dimensions were measured and compared between both positions. Results Five non-pregnant women, 6 healthy pregnant women at mid pregnancy and 8 healthy pregnant women at late pregnancy were enrolled in the study. In the group of non-pregnant women left ventricular (LV cardiac output (CO significantly decreased by 9% (p = 0.043 and right ventricular (RV end-diastolic volume (EDV significantly increased by 5% (p = 0.043 from the supine to the left lateral position. During mid pregnancy LV ejection fraction (EF, stroke volume (SV, left atrium lateral diameter and left atrial supero-inferior diameter increased significantly from the supine position to the left lateral position: 8%, 27%, 5% and 11%, respectively (p Conclusions During pregnancy positional changes affect significantly cardiac hemodynamic parameters and dimensions. Pregnant women who need serial studies by CMR should be imaged in a consistent position. From as early as 20 weeks the left lateral position should be preferred on the supine position because it positively affects venous return, SV and CO.

Postural adjustments in preterm infants at 4 and 6 months post-term during voluntary reaching in supine position

NARCIS (Netherlands)

Fallang, B; Saugstad, OD; Hadders-Algra, M

2003-01-01

Gradually it is getting clear that motor development - in particular balance control - in so-called "low-risk" preterm infants often differs from that in full-term infants. However, little is known on the etiology and pathophysiology of these problems. The aim of this study was to evaluate postural

Supine vs decubitus lateral patient positioning in vertebral fracture assessment.

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Paggiosi, Margaret Anne; Finigan, Judith; Peel, Nicola; Eastell, Richard; Ferrar, Lynne

2012-01-01

In vertebral fracture assessment (VFA), lateral scans are obtained with the patient positioned supine (C-arm densitometers) or lateral decubitus (fixed-arm densitometers). We aimed to determine the impact of positioning on image quality and fracture definition. We performed supine and decubitus lateral VFA in 50 postmenopausal women and used the algorithm-based qualitative method to identify vertebral fractures. We compared the 2 techniques for the identification of fractures (kappa analysis) and compared the numbers of unreadable vertebrae (indiscernible endplates) and vertebrae that were projected obliquely (Wilcoxon matched-pairs signed-rank test). The kappa score for agreement between the VFA techniques (to identify women with vertebral fractures) was 0.84 (95% confidence interval [CI]: 0.68-0.99), and for agreement with fracture assessments made from radiographs, kappa was 0.76 (95% CI: 0.57-0.94) for both supine and decubitus lateral VFA. There were more unreadable vertebrae with supine lateral (48 vertebrae in supine lateral compared with 14 in decubitus lateral; p=0.001), but oblique projection was less common (93 vertebrae compared with 145 in decubitus lateral; p=0.002). We conclude that there were significantly different projection effects with supine and decubitus lateral VFA, but these differences did not influence the identification of vertebral fractures in our study sample. Copyright © 2012 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

Risk factors for postural tachycardia syndrome in children and adolescents.

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Jing Lin

Full Text Available BACKGROUND: Postural tachycardia syndrome (POTS is prevalent in children and adolescents and has a great impact on health. But its risk factors have not been fully understood. This study aimed to explore possible risk factors for children and adolescents with POTS. METHODS AND FINDINGS: 600 children and adolescents (test group aged 7-18 (11.9 ± 3.0 years old, 259 males and 341 females, were recruited for identifying its risk factors. Another 197 subjects aged from 7 to 18 (11.3 ± 2.3 years old were enrolled in the validation group. Heart rate (HR and blood pressure (BP were monitored during upright test. Risk factors were analyzed and sensitivity and specificity for predicting POTS were tested via receiver operating characteristic curve. Among 600 subjects, 41 were confirmed with POTS patients (6.8% based on clinical manifestation and upright test. The results showed a significant difference in daily water intake, the daily sleeping hours, supine HR, HR increment and maximum HR during upright test between POTS and the unaffected children (P<0.05. Likelihood of POTS would increase by 1.583 times if supine HR was increased by 10 beats/min (95%CI 1.184 to 2.116, P<0.01, by 3.877 times if a child's water intake was less than 800 ml/day (95%CI 1.937 to 7.760, P<0.001, or by 5.905 times (95%CI 2.972 to 11.733, P<0.001 if sleeping hours were less than 8 hours/day. Supine HR, daily water intake and sleeping hours showed the capability of predicting POTS in children and adolescents with an AUC of 83.9% (95% CI: 78.6%-89.1%, sensitivity of 80.5% and specificity of 75%. Furthermore, in validation group, predictive sensitivity and specificity were 73.3% and 72.5%. CONCLUSION: Faster supine HR, less water intake and shorter sleeping hours were identified as risk factors for POTS.

The Effects of Multisensory Balance Training on Postural Control in Older Adults

OpenAIRE

Farnoosh Shams; Afsoun Hassani Mehraban; Ghorban Taghizadeh

2011-01-01

Objectives: It has been found that older adults fall or sway significantly more than younger ones under sensory conflict conditions. Considering the prospects of future increases in the elderly population size of Iran and the lack of proper postural control and the high costs of its probable consequences, this study investigated the effects of multi balance training on postural control. Methods & Materials: In this semi-experimental study, 34 elderly women participated in two training and...

Orthostatic Dysregulation during Postural Change on the Dental Chair and Intraoperative Monitoring by Heart Rate Variability Analysis

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Yukihiro Momota

2014-01-01

Full Text Available This is the first case report of orthostatic dysregulation (OD manifested during postural change on the dental chair and intraoperatively monitored by heart rate variability (HRV analysis. OD-associated autonomic dysfunction is induced by postural changes and easily leads to disturbance in circulatory dynamics; however, most dental practices have not yet realized the importance of managing OD. We measured autonomic activity in a patient with OD during dental therapy and assessed the clinical significance of HRV analysis for OD. The patient was a 17-year-old Japanese female. She was diagnosed with impacted wisdom teeth and had no previous history of a distinct systemic disease. A surgical procedure to extract the teeth was safely performed under both local anesthesia and sedation with nitrous oxide and midazolam. After the surgery, her postural change to sitting induced orthostatic hypotension. HRV variables showed parasympathetic dominance due to the upright position. Subsequently, her posture was returned to supine, and atropine sulfate administration for the immediate treatment of OD returned her blood pressure to normal levels. HRV variables showed relative sympathetic dominance due to an atropine-derived parasympathetic blockade. HRV analysis revealed OD-associated autonomic dysfunction and should become a standard tool for safe and secure dental management of OD.

The diagnostic value of supine blood pressure in hypertension.

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Krzesiński, Paweł; Stańczyk, Adam; Gielerak, Grzegorz; Piotrowicz, Katarzyna; Banak, Małgorzata; Wójcik, Agnieszka

2016-04-01

Correct blood pressure (BP) measurement is crucial in the diagnosis of arterial hypertension (AH), and controversy exists whether supine BP should be treated as equal to sitting BP. The aim of this study was to evaluate the relation of supine BP to sitting BP and ambulatory BP with regard to identification of diagnostic cut-offs for hypertension. This study included 280 patients with AH (mean age: 44.3 ±10.6 years). The following measurements of BP were performed and analyzed: 1) sitting office blood pressure measurement (OSBP and ODBP); 2) supine BP (supSBP and supDBP), measured automatically (5 times with a 2-minute interval) during evaluation by the Niccomo device (Medis, Germany); 3) 24-hour ambulatory blood pressure (ABP) monitoring. The mean supSBP and supDBP were found to be lower than OSBP and ODBP (130.9 ±14.2 vs. 136.6 ±15.5 mm Hg and 84.8 ±9.4 vs. 87.8 ±10.2 mm Hg, respectively; p AUC: 0.820 vs. 0.550; sensitivity 80.7% vs. 57.4%; specificity 83.2% vs. 52.7%; p blood pressure during a 10-minute supine rest was lower than in the sitting position. The supine blood pressure ≥ 130/80 mm Hg was found to be a specific and sensitive threshold for hypertension.

Temporal changes in postural sway caused by ultrashort-acting hypnotics: triazolam and zolpidem.

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Nakamura, M; Ishii, M; Niwa, Y; Yamazaki, M; Ito, H

2005-01-01

Two ultrashort-acting hypnotics, triazolam 0.25 mg and zolpidem 10 mg, were studied for their effects on equilibrium function in humans. Eight healthy male subjects participated in a double-blind, placebo-controlled study after informed consent. They subjected to static equilibrium tests, oculomotor tests and an assay of drug concentrations in the blood. Zolpidem was statistically significant in postural sway in tandem stance test, as defined by parametric values of tracing sum length and polygonal area of foot pressure center measured by a gait analysis system. In the tandem stance test, triazolam was statistically significant in postural sway only as defined by the polygonal area. However, in the Romberg test, the only statistically significant difference in zolpidem use was observed in polygonal area values. Blood concentrations of triazolam and zolpidem were found to closely correlate with the extent of postural sway in both tandem stance and Romberg tests. In this study, zolpidem with minimal muscle-relaxant effect incurred imbalance more extensively than triazolam, which is known for its effect of muscle relaxation. In addition, gaze deviation nystagmus was observed only in zolpidem use in 5 of 8 subjects (62.5%). From these results, it is suggested that in the use of hypnotics, sway derives from the suppression of the central nervous system relevant to awakening rather than from muscle relaxation. The prior reference to blood concentrations of hypnotics should help improve safety care in minimizing loss of balance control and possible fall. Copyright 2005 S. Karger AG, Basel.

Postural variation of pulmonary diffusing capacity as a marker of lung microangiopathy in Indian patients with type 2 diabetes mellitus

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Avinash Kumar

2016-01-01

Full Text Available Introduction: Diabetes mellitus (DM is characterized by the presence of chronic hyperglycemia and formation of advanced glycation end products (AGEs. Interaction between AGE and its receptor leads to endothelial damage and microangiopathy. This study was undertaken to investigate the possibility of using a postural variation of diffusing capacity as an early marker of lung microangiopathy and its correlation with the level of adhesion molecules, HbA1c, duration of diabetes, and insulin resistance in type 2 DM (T2DM patients with and without microangiopathy. Materials and Methods: Forty patients having T2DM without any microangiopathy (n = 20 as well as with microangiopathy (n = 20, and 22 age and sex matched healthy controls were enrolled in this cross-sectional study. Measurement of lung volumes and capacities were done. DLco was measured in sitting and supine position. Levels of vascular cell adhesion molecule-1 (VCAM-1, E-selectin, fasting glucose, and insulin were estimated in plasma of the patients and compared with controls. Results: Restrictive type of ventilatory change was observed in DM patients. Diffusing capacity (% predicted in the supine position (P < 0.0001, postural change in DLco (P < 0.0001, and coefficient of diffusion were significantly less in DM patients as compared to controls. Plasma levels of VCAM-1 were significantly higher in DM patients without microangiopathy and negatively correlated (r = −0.4054, P = 0.0094 with Δ DLco in all diabetic subjects. All patients had significantly higher insulin resistance. Conclusion: Lack of postural increase in diffusing capacity in type 2 diabetic patients along with increased VCAM-1 levels could reflect the presence of an early microangiopathy of the small pulmonary vessels.

Postural blood pressure electrocardiographic changes are associated with falls in older people.

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Saedon, Nor Izzati; Zainal-Abidin, Imran; Chee, Kok Han; Khor, Hui Min; Tan, Kit Mun; Kamaruzzaman, Shahrul K; Chin, Ai-Vyrn; Poi, Philip J H; Tan, Maw Pin

2016-02-01

To determine the magnitude of postural blood pressure change, differences in ECG between fallers and non-fallers were measured. Postural blood pressure change is associated with symptoms of dizziness, presyncope, and syncope. In this cross-sectional study were included participants from The Malaysian Falls Assessment and Intervention Trial: fallers, aged 65 years or older with two or more falls or one injurious fall in 12 months, from a teaching hospital; and non-fallers, aged 65 years and older found through word-of-mouth and advertising. Noninvasive beat-to-beat blood pressure was measured at 10 min supine rest and 3 min standing. The maximal drop in systolic and diastolic pressure was calculated from a 12-lead ECG interpreted by a cardiologist. Basic demographics, medical history, and symptoms of dizziness, presyncope, and syncope were recorded for all patients. We recruited 155 fallers and 112 non-fallers. Fallers had a significantly longer PR interval (179 ± 32 vs. 168 ± 27 ms, p = 0.013) and a longer corrected QT interval (449 ± 41 vs. 443 ± 39 msec, p = 0.008), and larger change in SBP (28 ± 14 vs. 19 ± 9 mmHg, p < 0.001) with posture change. SBP drop of ≥30mmHg associated with recurrent and injurious falls [odds ratio [95 % confidence interval] = 7.61 (3.18-18.21)]. The changes remained significant after adjustment for symptoms of dizziness, presyncope and syncope. Older individuals with recurrent and injurious falls have significantly longer PR and QT intervals and larger SBP reduction with posture change as compared to non-fallers, and these are not explained by the presence of dizziness, presyncope, or syncope. SBP cut-off of ≥30mmHg considered for postural measurements using continuous BP monitors, the significance of this value needs to be evaluated.

Semi-coarsening multigrid methods for parallel computing

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Jones, J.E.

1996-12-31

Standard multigrid methods are not well suited for problems with anisotropic coefficients which can occur, for example, on grids that are stretched to resolve a boundary layer. There are several different modifications of the standard multigrid algorithm that yield efficient methods for anisotropic problems. In the paper, we investigate the parallel performance of these multigrid algorithms. Multigrid algorithms which work well for anisotropic problems are based on line relaxation and/or semi-coarsening. In semi-coarsening multigrid algorithms a grid is coarsened in only one of the coordinate directions unlike standard or full-coarsening multigrid algorithms where a grid is coarsened in each of the coordinate directions. When both semi-coarsening and line relaxation are used, the resulting multigrid algorithm is robust and automatic in that it requires no knowledge of the nature of the anisotropy. This is the basic multigrid algorithm whose parallel performance we investigate in the paper. The algorithm is currently being implemented on an IBM SP2 and its performance is being analyzed. In addition to looking at the parallel performance of the basic semi-coarsening algorithm, we present algorithmic modifications with potentially better parallel efficiency. One modification reduces the amount of computational work done in relaxation at the expense of using multiple coarse grids. This modification is also being implemented with the aim of comparing its performance to that of the basic semi-coarsening algorithm.

Leg blood pressure measured in orthostatic posture is associated with left ventricular mass in normotensive subjects.

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Gemignani, Tiago; Matos-Souza, José R; Franchini, Kleber G; Nadruz, Wilson

2012-10-01

Changing from a supine to an orthostatic posture is associated with substantial increments in leg blood pressure (BP) levels, which could ultimately influence the hemodynamic burden imposed on the heart. This study investigated the relationship between brachial and leg BP measurements and the left cardiac chamber's structure and assessed the role of body posture changes in this regard. One hundred and thirty normotensive, nondiabetic, nonsmoking, normolipemic subjects were evaluated by a clinical history, anthropometry, the analysis of metabolic parameters, echocardiography, and the measurement of BP in the arm and the calf in both supine and orthostatic positions. Significant correlation coefficients between the leg BP measurements and the cardiac structure were detected, especially between the orthostatic pulse pressure (PP) and the left ventricular (LV) wall thickness (r = 0.38; P < 0.001), the orthostatic PP and the LV mass (r = 0.37; P < 0.001), and the orthostatic systolic BP (SBP) and the left atrial size (r = 0.35; P < 0.001). Stepwise and standard regression analysis adjusted for brachial BP and anthropometric and metabolic variables confirmed that the leg orthostatic PP was independently related to the LV wall thickness and mass. Moreover, the leg orthostatic SBP was associated with the left atrial dimension even after adding the LV mass to the statistical models. Finally, triglyceride levels and body surface area showed significant relationship with leg orthostatic PP and SBP, whereas brachial orthostatic PP and SBP were only associated with age and anthropometric variables. Orthostatic leg BP is independently associated with the cardiac structure in normotensive subjects.

Phobic postural vertigo treated with autogenic training: a case report.

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Goto, Fumiyuki; Nakai, Kimiko; Kunihiro, Takanobu; Ogawa, Kaoru

2008-09-30

Patients suffering from dizziness due to vertigo are commonly encountered in the department of otolaryngology. If various clinical examinations do not reveal any objective findings, then the patients are referred to the department of internal medicine or psychiatry. In many cases, the diagnosis is psychological dizziness. Phobic postural vertigo, which was first reported by Brandt T et al in 1994, is supposed to be a type of psychological dizziness. The diagnosis is based on 6 characteristics proposed by Brandt et al. Patients are usually treated with conventional medical therapy, but some cases may be refractory to such a therapy. Psychotherapy is recommended in some cases; however, psychotherapy including autogenic training, which can be used for general relaxation, is not widely accepted. This paper describes the successful administration of autogenic training in a patient suffering from phobic postural vertigo. We present a case of a patient who suffered from phobic postural vertigo. A 37-year-old female complained of dizziness. She had started experiencing dizziness almost 3 years She was intractable to many sort of conventional therapy. In the end, her symptom disappeared after introduction of autogenic training. Autogenic training can be a viable and acceptable treatment option for phobic postural vertigo patients who fail to respond to other therapies. This case emphasizes the importance of autogenic training as a method to control symptom of phobic postural vertigo.

Blood pressure associates with standing balance in elderly outpatients.

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Jantsje H Pasma

Full Text Available OBJECTIVES: Assessment of the association of blood pressure measurements in supine and standing position after a postural change, as a proxy for blood pressure regulation, with standing balance in a clinically relevant cohort of elderly, is of special interest as blood pressure may be important to identify patients at risk of having impaired standing balance in routine geriatric assessment. MATERIALS AND METHODS: In a cross-sectional cohort study, 197 community-dwelling elderly referred to a geriatric outpatient clinic of a middle-sized teaching hospital were included. Blood pressure was measured intermittently (n = 197 and continuously (subsample, n = 58 before and after a controlled postural change from supine to standing position. The ability to maintain standing balance was assessed during ten seconds of side-by-side, semi-tandem and tandem stance, with both eyes open and eyes closed. Self-reported impaired standing balance and history of falls were recorded by questionnaires. Logistic regression analyses were used to examine the association between blood pressure and 1 the ability to maintain standing balance; 2 self-reported impaired standing balance; and 3 history of falls, adjusted for age and sex. RESULTS: Blood pressure decrease after postural change, measured continuously, was associated with reduced ability to maintain standing balance in semi-tandem stance with eyes closed and with increased self-reported impaired standing balance and falls. Presence of orthostatic hypotension was associated with reduced ability to maintain standing balance in semi-tandem stance with eyes closed for both intermittent and continuous measurements and with increased self-reported impaired standing balance for continuous measurements. CONCLUSION: Continuous blood pressure measurements are of additional value to identify patients at risk of having impaired standing balance and may therefore be useful in routine geriatric care.

Comparison of supine and prone positions for percutaneous nephrolithotomy in treatment of staghorn stones.

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Gökce, Mehmet İlker; Ibiş, Arif; Sancı, Adem; Akıncı, Aykut; Bağcı, Uygar; Ağaoğlu, Eylül Asya; Süer, Evren; Gülpınar, Ömer

2017-12-01

Percutaneous nephrolithotomy (PNL) is the primary treatment modality for management of staghorn stones. PNL in supine position has important advantages over prone positon. However, studies comparing prone and supine positions for PNL in staghorn stone patients have conflicting results, and the aim of the current study was to compare prone and supine positions for PNL in staghorn stone cases. Data of patients underwent PNL for staghorn stones in supine or prone position by a single urologist were collected prospectively. The supine and prone position groups were compared for stone free rate (SFR) and complication rates. All patients were evaluated with NCCT for evaluation of SFR. Chi-square test was used to compare categorical variables and Student t test was applied for continuous variables of the treatment groups. The groups were similar for demographic and stone-related characteristics. Multi-caliceal and intercostal access was more common in prone position. Operation duration was significantly shorter and hemoglobin drop was significantly less in supine group. SFR was 64.1 and 60.4% in the supine and prone groups, respectively (p = 0.72). Complication rates were similar in the two groups but Clavien III complications were observed in two patients in the prone group. PNL in supine position is an effective treatment for management of staghorn stones. The need for multi-caliceal and intercostal puncture is less when combined with retrograde intrarenal surgery. PNL in supine position should be considered as primary treatment option in staghorn stone cases.

Evaluation of Neutral Body Posture on Shuttle Mission STS-57 (SPACEHAB-1). Revision

Science.gov (United States)

Mount, Frances E.; Whitmore, Mihriban; Stealey, Sheryl L.

2003-01-01

Research has shown that the space environment induces physiological changes in the human body, such as fluid shifts in the upper body and chest cavity, spinal lengthening, muscular atrophy, space motion sickness, cardiopulmonary deconditioning, and bone mass loss, as well as some changes in visual perception. These require a period of adaptation and can substantially affect both crew member performance and posture. These physiological effects, when work activities are conducted, have been known to impact the body's center of gravity, reach, flexibility, and dexterity. All these aspects of posture must be considered to safely and efficiently design space systems and hardware. NASA has documented its microgravity body posture in the Man-Systems Integration Standards (MSIS); the space community uses the MSIS posture to design workstations and tools for space application. However, the microgravity body posture should be further investigated for several reasons, including small sample size in previous studies, possible imprecision, and lack of detail. JSC undertook this study to investigate human body posture exhibited under microgravity conditions. STS-57 crew members were instructed to assume a relaxed posture that was not oriented to any work area or task. Crew members were asked to don shorts and tank tops and to be blindfolded while data were recorded. Video data were acquired once during the mission from each of the six crew members. No one crew member exhibited the typical NBP called out in the MSIS; one composite posture is not adequate. A range of postures may be more constructive for design purposes. Future evaluations should define precise posture requirements for workstation, glove box, maintenance, foot-restraint, and handhold activities.

A Prospective Study of Intrafraction Prostate Motion in the Prone vs. Supine Position

International Nuclear Information System (INIS)

Wilder, Richard B.; Chittenden, Lucy; Mesa, Albert V.; Bunyapanasarn, Jane; Agustin, Jeff; Lizarde, Jessica; Ravera, John; Tokita, Kenneth M.

2010-01-01

Purpose: To prospectively analyze prostate intrafraction motion in the prone vs. supine position and to assess patient satisfaction with these two positions. Methods and Materials: Fifteen prostate cancer patients underwent implantation of five fiducial gold seeds in their prostate for localization. Patients were treated with high-dose-rate brachytherapy to 2,200 cGy followed by intensity-modulated radiation therapy (IMRT) to 5,040 cGy. Patients underwent computed tomography simulation and IMRT in the prone position. For the first five IMRT treatments, an electronic portal imaging system was used to acquire anteroposterior (AP) and lateral images pretreatment and posttreatment. We then repositioned each patient supine and repeated the process, resulting in 600 images. Results: Mean ± standard deviation intrafraction prostate motion was 2.1 ± 1.2 mm and 1.7 ± 1.4 mm (AP, p = 0.47), 2.2 ± 2.0 mm and 1.6 ± 1.8 mm (superoinferior, p = 0.16), and 1.0 ± 1.2 mm and 0.6 ± 0.9 mm (left-right, p = 0.03) in the prone and supine positions, respectively. Eighty percent of patients stated that they were more comfortable in the supine position (p = 0.02). Conclusions: Prone and supine positions resulted in a similar magnitude of AP and superoinferior intrafraction prostate motion (2 mm). Because there was no significant difference in the magnitude of AP and superoinferior prostate motion prone vs. supine and patients were more comfortable in the supine position, patients now undergo IMRT to the prostate and seminal vesicles at our center in the supine position.

Activities, postures and comfort perception of train passengers as input for train seat design

NARCIS (Netherlands)

Groenesteijn, L.; Hiemstra-van Mastrigt, S.; Gallais, C.; Blok, M.; Kuijt-Evers, L.; Vink, P.

2014-01-01

Working in the train is a part of new ways of working. However, the ideal working position is unknown. Moreover, the ideal position for leisure and relaxing is also unknown. This article defines what activities train passengers mainly perform and which corresponding postures are seen. Based on the

Supinated forearm is correlated with the onset of medial epicondylitis in professional slalom water-skiers.

Science.gov (United States)

Rosa, Donato; Di Donato, Sigismondo Luca; Balato, Giovanni; D'Addona, Alessio; Schonauer, Fabrizio

2016-01-01

prolonged and laborious activities involving wrists and forearms has been long associated with the onset of epicondylitis. Slalom water-skiing can be included in this category. The purpose of the study is to analyse the correlation between the pronated or supinated position of forearms during water-skiing practice and the presence respectively of lateral and medial epicondylitis. sixty-six pro and semi-pro slalom water-skiers were enrolled in the study. A questionnaire was submitted to each athlete. Diagnosis of lateral or medial epicondylitis was made through anamnesis and clinical exam by an expert orthopaedic surgeon. Chi-squared were performed for categorical variables, and Mann-Whitney U test for continuous ones. from 116 upper limbs examined, we observed 15 (12.9%) cases of lateral epicondylitis, 30 (25.9%) cases of medial epicondylitis, 10 (8.6%) were affected by both lateral and medial epicondylitis. Lateral and medial epicondylitis were associated (95% C.I.=2,489-26,355; P=epicondylitis (95% C.I.=1,529-9,542; P=0.003). slalom water-skiing can be considered a high-risk sport for epicondylitis. In slalom water-skiers there is a correlation between development of lateral and medial epicondylitis in the same upper limb. Supinated position of forearms is strongly associated with the diagnosis of medial epicondylitis.

Lung volumes during sustained microgravity on Spacelab SLS-1

Science.gov (United States)

Elliott, Ann R.; Prisk, G. Kim; Guy, Harold J. B.; West, John B.

1994-01-01

Gravity is known to influence the mechanical behavior of the lung and chest wall. However, the effect of sustained microgravity (microgravity) on lung volumes has not been reported. Pulmonary function tests were performed by four subjects before, during, and after 9 days of microgravity exposure. Ground measurements were made in standing and supine postures. Tests were performed using a bag-in-box-and-flowmeter system and a respiratory mass spectrometer. Measurements included functional residual capacity (FRC), expiratory reserve volume (ERV), residual volume (RV), inspiratory and expiratory vital capacities (IVC and EVC), and tidal volume (V9sub T)). Total lung capacity (TLC) was derived from the measured EVC and RV values. With preflight standing values as a comparison, FRC was significantly reduced by 15% (approximately 500 ml) in microgravity and 32% in the supine posture. ERV was reduced by 10 - 20% in microgravity and decreased by 64% in the supine posture. RV was significantly reduced by 18% (310 ml) in microgravity but did not significantly change in the supine posture compared with standing. IVC and EVC were slightly reduced during the first 24 h of microgravity but returned to 1-G standing values within 72 h of microgravity exposure. IVC and EVC in the supine posture were significantly reduced by 12% compared with standing. During microgravity, V(sub T) decreased by 15% (approximately 90 ml), but supine V(sub T) was unchanged compared with preflight standing values. TLC decreased by approximately 8% during microgravity and in the supine posture compared with preflight standing. The reductions in FRC, ERV, and RV during microgravity are probably due to the cranial shift of the diaphragm, an increase in intrathoracic blood volume, and more uniform alveolar expansion.

Comparison of supine and prone craniospinal irradiation in children with medulloblastoma.

Science.gov (United States)

Verma, Jonathan; Mazloom, Ali; Teh, Bin S; South, Michael; Butler, E Brian; Paulino, Arnold C

2015-01-01

To compare port film rejection and treatment outcome according to craniospinal irradiation (CSI) position for medulloblastoma. We retrospectively searched for patients ≤19 years treated with CSI for medulloblastoma at 1 department. We collected the following data: age; sex; risk group; need for general anesthesia; radiation therapy (RT) dose and fractionation; and the acceptance or rejection of weekly port films during treatment. We also collected data on outcomes, including neuraxis recurrence and possible complications such as myelitis. Of 46 children identified, 23 were treated prone (median age, 8.1 years) and 23 supine (median age, 7.2 years). High-risk disease was seen in 26% of prone and 35% of supine patients (P = .25). There was no difference in use of general anesthesia between those treated prone versus supine (57% vs 61%). The rejection rate of cranial port films in the prone position was 35%, which was significantly higher than the rate of 8% in patients treated supine (P < .0001). The 5-year progression-free (P = .37) and overall survival (P = .18) rates were 62% and 67% for prone and 76% and 84% for supine patients. There were no isolated junctional failures or radiation myelitis in either CSI position. The supine position for CSI was found to have similar survival outcomes compared with the prone position. A higher proportion of rejected cranial port films was seen in children treated in the prone position. Copyright © 2015 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

Semi-definite Programming: methods and algorithms for energy management

International Nuclear Information System (INIS)

Gorge, Agnes

2013-01-01

The present thesis aims at exploring the potentialities of a powerful optimization technique, namely Semi-definite Programming, for addressing some difficult problems of energy management. We pursue two main objectives. The first one consists of using SDP to provide tight relaxations of combinatorial and quadratic problems. A first relaxation, called 'standard' can be derived in a generic way but it is generally desirable to reinforce them, by means of tailor-made tools or in a systematic fashion. These two approaches are implemented on different models of the Nuclear Outages Scheduling Problem, a famous combinatorial problem. We conclude this topic by experimenting the Lasserre's hierarchy on this problem, leading to a sequence of semi-definite relaxations whose optimal values tends to the optimal value of the initial problem. The second objective deals with the use of SDP for the treatment of uncertainty. We investigate an original approach called 'distributionally robust optimization', that can be seen as a compromise between stochastic and robust optimization and admits approximations under the form of a SDP. We compare the benefits of this method w.r.t classical approaches on a demand/supply equilibrium problem. Finally, we propose a scheme for deriving SDP relaxations of MISOCP and we report promising computational results indicating that the semi-definite relaxation improves significantly the continuous relaxation, while requiring a reasonable computational effort. SDP therefore proves to be a promising optimization method that offers great opportunities for innovation in energy management. (author)

CHARACTERISTICS OF MAXIMUM PERFORMANCE OF PEDALING EXERCISE IN RECUMBENT AND SUPINE POSITIONS

Directory of Open Access Journals (Sweden)

Morimasa Kato

2011-09-01

Full Text Available To determine the characteristics of maximum pedaling performance in the recumbent and supine positions, maximum isokinetic leg muscle strength was measured in eight healthy male subjects during pedaling at three velocities (300°/s, 480°/s, and 660°/s, and maximum incremental tests were performed for each position. The maximum isokinetic muscle strength in the recumbent position was 210.0 ± 29.2 Nm at 300°/s, 158.4 ± 19.8 Nm at 480°/s, and 110.6 ± 13.2 at 660°/s. In contrast, the muscle strength in the supine position was 229.3 ± 36.7 Nm at 300°/s, 180. 7 ± 20.3 Nm at 480°/s, and 129.6 ± 14.0 Nm at 660°/s. Thus, the maximum isokinetic muscle strength showed significantly higher values in the supine position than in the recumbent position at all angular velocities. The knee and hip joint angles were measured at peak torque using a goniometer; the knee joint angle was not significantly different between both positions, whereas the hip joint angle was greater in the supine position than in the recumbent position (Supine position: 137.3 ± 9. 33 degree at 300°/s, 140.0 ± 11.13 degrees at 480°/s, and 141.0 ± 9.61 degrees at 660°/s. Recumbent position: 99.5 ± 12.21 degrees at 300°/s, 101.6 ± 12.29 degrees at 480°/s, and 105.8 ± 14.28 degrees at 660°/s. Peak oxygen uptake was higher in the recumbent position (50.3 ± 4.43 ml·kg-1·min-1 than in the supine position (48.7 ± 5.10 ml·kg-1·min-1. At maximum exertion, the heart rate and whole-body rate of perceived exertion (RPE were unaffected by position, but leg muscle RPE was higher in the supine position (19.5 ± 0.53 than in the recumbent position (18.8 ± 0.71. These results suggest that the supine position is more suitable for muscle strength exertion than the recumbent position, and this may be due to different hip joint angles between the positions. On the contrary, the endurance capacity was higher in the recumbent position than in the supine position. Since leg muscle

Sonographic appearance of a partial rupture of the supinator muscle.

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Chen, Chih-Chun; Chiou, Hong-Jen; Kao, Chung-Lan; Chan, Rai-Chi

2008-05-01

We report the case of a 51-year-old woman who experienced pain and swelling in the right forearm after spinning cotton. History taking and physical examinations helped identify a tear of the supinator muscle, which was confirmed via sonographic examination. To our knowledge, this article is the first report of a supinator muscle tear diagnosed with sonography. (c) 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008.

A Simple Technique of Supine Craniospinal Irradiation

International Nuclear Information System (INIS)

Munshi, Anusheel; Jalali, Rakesh

2008-01-01

We describe a simple procedure of craniospinal irradiation in supine position. The procedure was carried out with a 100-cm isocenter linear accelerator and compatible simulator. Treatment was with a 1 or 2 posteroanterior (PA)-directed spinal fields abutting lateral-directed cranial fields. Abutment of the fields was established by placement of markers on the neck of the patient, which provided a measure of the divergence of the spinal field. The precision and reproducibility of this technique, including the placement of junctions, appeared to be as good as for treatment in the prone position. The same could be verified with port films. We conclude that this new technique of supine craniospinal treatment is a simple and convenient alternative to traditional treatment in the prone position

An adaptive technique for multiscale approximate entropy (MAEbin) threshold (r) selection: application to heart rate variability (HRV) and systolic blood pressure variability (SBPV) under postural stress.

Science.gov (United States)

Singh, Amritpal; Saini, Barjinder Singh; Singh, Dilbag

2016-06-01

Multiscale approximate entropy (MAE) is used to quantify the complexity of a time series as a function of time scale τ. Approximate entropy (ApEn) tolerance threshold selection 'r' is based on either: (1) arbitrary selection in the recommended range (0.1-0.25) times standard deviation of time series (2) or finding maximum ApEn (ApEnmax) i.e., the point where self-matches start to prevail over other matches and choosing the corresponding 'r' (rmax) as threshold (3) or computing rchon by empirically finding the relation between rmax, SD1/SD2 ratio and N using curve fitting, where, SD1 and SD2 are short-term and long-term variability of a time series respectively. None of these methods is gold standard for selection of 'r'. In our previous study [1], an adaptive procedure for selection of 'r' is proposed for approximate entropy (ApEn). In this paper, this is extended to multiple time scales using MAEbin and multiscale cross-MAEbin (XMAEbin). We applied this to simulations i.e. 50 realizations (n = 50) of random number series, fractional Brownian motion (fBm) and MIX (P) [1] series of data length of N = 300 and short term recordings of HRV and SBPV performed under postural stress from supine to standing. MAEbin and XMAEbin analysis was performed on laboratory recorded data of 50 healthy young subjects experiencing postural stress from supine to upright. The study showed that (i) ApEnbin of HRV is more than SBPV in supine position but is lower than SBPV in upright position (ii) ApEnbin of HRV decreases from supine i.e. 1.7324 ± 0.112 (mean ± SD) to upright 1.4916 ± 0.108 due to vagal inhibition (iii) ApEnbin of SBPV increases from supine i.e. 1.5535 ± 0.098 to upright i.e. 1.6241 ± 0.101 due sympathetic activation (iv) individual and cross complexities of RRi and systolic blood pressure (SBP) series depend on time scale under consideration (v) XMAEbin calculated using ApEnmax is correlated with cross-MAE calculated using ApEn (0.1-0.26) in steps of 0

SU-E-T-307: Dosimetric Comparison of Prone Versus Supine Positioning for Adjuvant Breast Radiation Therapy

International Nuclear Information System (INIS)

Pope, C; O’Connor, B; Hayes, L; Rella, J; Ruiz, B; Yang, J

2015-01-01

Purpose: The prone treatment position has been used to reduce ipsilateral lung and heart dose in left breast radiation. We conducted a retrospective study to evaluate the difference in the dosimetry between prone and supine treatment positions. Methods: Eight left breast cancer patients were simulated in both the supine and prone positions as a pretreatment evaluation for the optimal treatment position. Treatment plans were created for all patients in both the supine and prone positions using a field in field three dimensional planning technique. Prescribed dose was 45 Gy delivered by two tangential photon fields. Irradiated volume (IV) was evaluated by V50, V100, and dose to lung and heart by V5, V10, V20, and the mean dose were evaluated. Results: All dosimetry metrics for both the supine and prone plans met our internal normal structure guidelines which are based on Quantec data. The average IVs (50% and 100%) were 2223cc and 1361cc prone, 2315cc and 1315cc supine. The average ipsilateral lung Mean dose (0.83Gy prone vs 5.8Gy supine), V5 (1.6% prone vs 20.9% supine), V10 (0.78% prone vs 15% supine) and V20 (0.36% prone vs 11% supine) were significantly lower in prone position. Heart Mean dose (1.4Gy prone vs 2.9Gy supine), V10 (1.4% prone vs 5.0% supine) and V20 (0.4% prone vs 3.5% supine) were found improved for all patients except one where the mean dose was the same and all other values were improved. Conclusion: The prone position offer preferable dosimetry for all patients planned in our study. These patients were chosen based on the physician’s belief that they would benefit from prone treatment either because they had large pendulous breasts or due to the amount of heart seen in the field on CT simulation

CT simulation technique for craniospinal irradiation in supine position

International Nuclear Information System (INIS)

Lee, Suk; Kim, Yong Bae; Chu, Sung Sil; Suh, Chang Ok; Kwon, Soo Il

2002-01-01

In order to perform craniospinal irradiation (CSI) in the supine position on patients who are unable to lie in the prone position, a new simulation technique using a CT simulator was developed and its availability was evaluated. A CT simulator and a 3-D conformal treatment planning system were used to develop CSI in the supine position. The head and neck were immobilized with a thermoplastic mask in the supine position and the entire body was immobilized with a Vac-Loc. A volumetric image was then obtained using the CT simulator. In order to improve the reproducibility of the patients' setup, datum lines and points were marked on the head and the body. Virtual fluoroscopy was performed with the removal of visual obstacles such as the treatment table or the immobilization devices. After the virtual simulation, the treatment isocenters of each field were marked on the body and the immobilization devices at the conventional simulation room. Each treatment field was confirmed by comparing the fluoroscopy images with the digitally reconstructed radiography (DRR)/digitally composite radiography (DCR) images from the virtual simulation. The port verification films from the first treatment were also compared with the DRR/DCR images for a geometrical verification. CSI in the supine position was successfully performed in 9 patients. It required less than 20 minutes to construct the immobilization device and to obtain the whole body volumetric images. This made it possible to not only reduce the patients' inconvenience, but also to eliminate the position change variables during the long conventional simulation process. In addition, by obtaining the CT volumetric image, critical organs, such as the eyeballs and spinal cord, were better defined, and the accuracy of the port designs and shielding was improved. The difference between the DRRs and the portal films were less than 3 mm in the vertebral contour. CSI in the supine position is feasible in patients who cannot lie on

CT simulation technique for craniospinal irradiation in supine position

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Lee, Suk; Kim, Yong Bae; Chu, Sung Sil; Suh, Chang Ok [Yonsei Cancer Center, College of Medicine, Yonsei University, Seoul (Korea, Republic of); Kwon, Soo Il [Kyonggi University, Seoul (Korea, Republic of)

2002-06-15

In order to perform craniospinal irradiation (CSI) in the supine position on patients who are unable to lie in the prone position, a new simulation technique using a CT simulator was developed and its availability was evaluated. A CT simulator and a 3-D conformal treatment planning system were used to develop CSI in the supine position. The head and neck were immobilized with a thermoplastic mask in the supine position and the entire body was immobilized with a Vac-Loc. A volumetric image was then obtained using the CT simulator. In order to improve the reproducibility of the patients' setup, datum lines and points were marked on the head and the body. Virtual fluoroscopy was performed with the removal of visual obstacles such as the treatment table or the immobilization devices. After the virtual simulation, the treatment isocenters of each field were marked on the body and the immobilization devices at the conventional simulation room. Each treatment field was confirmed by comparing the fluoroscopy images with the digitally reconstructed radiography (DRR)/digitally composite radiography (DCR) images from the virtual simulation. The port verification films from the first treatment were also compared with the DRR/DCR images for a geometrical verification. CSI in the supine position was successfully performed in 9 patients. It required less than 20 minutes to construct the immobilization device and to obtain the whole body volumetric images. This made it possible to not only reduce the patients' inconvenience, but also to eliminate the position change variables during the long conventional simulation process. In addition, by obtaining the CT volumetric image, critical organs, such as the eyeballs and spinal cord, were better defined, and the accuracy of the port designs and shielding was improved. The difference between the DRRs and the portal films were less than 3 mm in the vertebral contour. CSI in the supine position is feasible in patients who cannot

The supinated mediolateral radiograph for detection of humeral head osteochondrosis in the dog

International Nuclear Information System (INIS)

Callahan, T.F.; Ackerman, N.

1985-01-01

Mediolateral and supinated mediolateral radiographs of the shoulder joint were compared in 19 dogs. Twenty shoulders, representing 15 dogs (5 had bilateral lesions), had osteochondrosis of the humeral head. The flattened humeral head and subchondral defect were detectable in both views in all affected shoulders. The lesions were slightly more easily detected in the supinated view. The supinated view more consistently demonstrated the presence of a calcified cartilage flap and therefore, could be useful in determining a course of therapy. In four dogs (8 shoulders) without osteochondrosis and six normal shoulders from affected dogs, there were no instances in which a shoulder appeared normal on one view, but demonstrated a lesion on the other. The supinated view should be obtained in addition to the mediolateral view in dogs with osteochondrosis of the humeral head

Comparison of supine, upright, and prone positions for liver scans

International Nuclear Information System (INIS)

Harolds, J.A.; Brill, A.B.; Patton, J.A.; Touya, J.J.

1983-01-01

We compared liver scan interpretations based on anterior images obtained in the upright, prone, and supine positions. Receiver-operating-characteristic curves were generated for three well trained observers. Results showed that reading the three different views together was more accurate than the reading of any individual image. Furthermore, interpretations based on either the prone or upright view were superior to those using the supine view alone. The prone and upright views should be used more often in liver scanning

Ventilatory sensitivity to mild asphyxia: prone versus supine sleep position

OpenAIRE

Galland, B; Bolton, D; Taylor, B; Sayers, R; Williams, S

2000-01-01

AIMS—To compare the effects of prone and supine sleep position on the main physiological responses to mild asphyxia: increase in ventilation and arousal.
METHODS—Ventilatory and arousal responses to mild asphyxia (hypercapnia/hypoxia) were measured in 53 healthy infants at newborn and 3 months of age, during quiet sleep (QS) and active sleep (AS), and in supine and prone sleep positions. The asphyxial test mimicked face down rebreathing by slowly altering the inspired air: C...

MRI measurements of intracranial pressure in the upright posture: The effect of the hydrostatic pressure gradient.

Science.gov (United States)

Alperin, Noam; Lee, Sang H; Bagci, Ahmet M

2015-10-01

To add the hydrostatic component of the cerebrospinal fluid (CSF) pressure to magnetic resonance imaging (MRI)-derived intracranial pressure (ICP) measurements in the upright posture for derivation of pressure value in a central cranial location often used in invasive ICP measurements. Additional analyses were performed using data previously collected from 10 healthy subjects scanned in supine and sitting positions with a 0.5T vertical gap MRI scanner (GE Medical). Pulsatile blood and CSF flows to and from the brain were quantified using cine phase-contrast. Intracranial compliance and pressure were calculated using a previously described method. The vertical distance between the location of the CSF flow measurement and a central cranial location was measured manually in the mid-sagittal T1 -weighted image obtained in the upright posture. The hydrostatic pressure gradient of a CSF column with similar height was then added to the MR-ICP value. After adjustment for the hydrostatic component, the mean ICP value was reduced by 7.6 mmHg. Mean ICP referenced to the central cranial level was -3.4 ± 1.7 mmHg compared to the unadjusted value of +4.3 ± 1.8 mmHg. In the upright posture, the hydrostatic pressure component needs to be added to the MRI-derived ICP values for compatibility with invasive ICP at a central cranial location. © 2015 Wiley Periodicals, Inc.

Effects of Corrective Exercise for Thoracic Hyperkyphosis on Posture, Balance, and Well-Being in Older Women: A Double-Blind, Group-Matched Design.

Science.gov (United States)

Jang, Hyun-Jeong; Hughes, Lynne C; Oh, Duck-Won; Kim, Suhn-Yeop

2017-09-13

The purpose of this study was to identify the effects of a corrective exercise for thoracic hyperkyphosis on posture, balance, and well-being in Korean community-dwelling older women. Fifty women 65 years of age and older, recruited from 2 senior centers, participated in this study. Participants were assigned to either the experimental group (EG) or the control group (CG) on the basis of convenience of location, and 22 in each were analyzed. Participants in the EG underwent a thoracic corrective exercise program 1 hour each session, twice per week for 8 weeks (a total of 16 sessions), which consisted of specific exercises to enhance breathing, thoracic mobility and stability, and awareness of thoracic alignment. The CG received education on the same thoracic corrective exercise program and a booklet of the exercises. Outcome measures included the extent of postural abnormality (angle of thoracic kyphosis, kyphosis index calculated both in relaxed- and best posture using flexicurve, the ratio of the kyphosis index calculated best posture/relaxed posture, craniovertebral angle, and tragus-to-wall distance), balance (Short Physical Performance Battery and limit of stability), and well-being (Geriatric Depression Scale Short Form and the 36-Item Short Form Health Survey [SF-36]). All data were collected by 6 blinded assessors at baseline, at 8 weeks after the completion of intervention, and at 16 weeks for follow-up. For participants of the EG, means of all parameters showed significant improvements over time (P posture, balance, and well-being in older women with thoracic hyperkyphosis. We recommend the use of the therapeutic strategies utilized in this study to enhance thoracic posture, balance, and well-being of older women with thoracic hyperkyphosis. Future research is needed to apply this exercise protocol on a larger and more diverse population.

AN EVALUATION OF THE REARFOOT POSTURE IN INDIVIDUALS WITH PATELLOFEMORAL PAIN SYNDROME

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Wendy Gilleard

2004-11-01

Full Text Available Structural abnormalities of the foot may cause abnormal subtalar joint compensatory motion in order to attain normal function of the lower extremity during gait although studies have not been conclusive. Current conflict in the literature may be related to the differing measures focused on the varying protocols and also the absence of a control group in some studies. This study investigated the rearfoot posture including Subtalar Joint Neutral Position (STJN and Relaxed Calcaneal Standing (RCS measurements in patellofemoral pain syndrome (PFPS and healthy subjects. The angle of STJN during non-weight bearing position and the two dimensional (2D rearfoot RCS posture was measured using a goniometer in 14 healthy females and 13 females with PFPS. The RCS posture was also measured three dimensionally (3D by attaching external markers to a tibia shell and the calcaneus and videoing with a four-camera three-dimensional motion analysis system. A one way ANOVA was used to assess the differences between the groups. The 2D and 3D RCS were significantly different between the groups (p ¡Ü 0.001 with mean -0.23¡ã ¡À 1.35¡ã , 2.52¡ã ¡À 3.11¡ã for the control group and 2.35¡ã ¡À 1.4¡ã, 7.02¡ã ¡À 3.33¡ã for the clinical group respectively. STJN showed a slight rearfoot varus (although significant p = 0.04 in PFPS (-2.20¡ã ¡À 1.51¡ã compared to the control group (-1.00¡ã ¡À 1.36¡ã. Negative values indicated inversion and positive values indicated eversion. The 2D and 3D RCS showed a significantly more everted posture of the rearfoot for the PFPS group. Subtalar joint varus may contribute to the increased eversion during relaxed standing in the PFPS group. Rearfoot measurements may be an important addition to other clinical measurements taken to explore the underlying aetiology of subjects with PFPS.

A multicentre randomized controlled trial of gentle assisted pushing in the upright posture (GAP) or upright posture alone compared with routine practice to reduce prolonged second stage of labour (the Gentle Assisted Pushing study): study protocol.

Science.gov (United States)

Hofmeyr, G Justus; Singata, Mandisa; Lawrie, Theresa; Vogel, Joshua P; Landoulsi, Sihem; Seuc, Armando H; Gülmezoglu, A Metin

2015-12-16

Fundal pressure (pushing on the upper part of the uterus in the direction of the birth canal) is often performed in routine practice, however the benefit and indications for its use are unclear and vigorous pressure is potentially harmful. There is some evidence that it may be applied routinely or to expedite delivery in some situations (e.g. fetal distress or maternal exhaustion), particularly in settings where other methods of achieving delivery (forceps, vacuum) are not available. Gentle assisted pushing (GAP) is an innovative method of applying gentle but steady pressure to the uterine fundus with the woman in an upright posture. This trial aims to evaluate the use of GAP in an upright posture, or upright posture alone, on reducing the mean time of delivery and the associated maternal and neonatal complications in women not having delivered following 15-30 min in the second stage of labour. We will conduct a multicentre, randomized, unblinded, controlled trial with three parallel arms (1:1:1). 1,145 women will be randomized at three hospitals in South Africa. Women will be eligible for inclusion if they are ≥18 years old, nulliparous, gestational age ≥ 35 weeks, have a singleton pregnancy in cephalic presentation and vaginal delivery anticipated. Women with chronic medical conditions or obstetric complications are not eligible. If eligible women are undelivered following 15-30 min in the second stage of labour, they will be randomly assigned to: 1) GAP in the upright posture, 2) upright posture only and 3) routine practice (recumbent/supine posture). The primary outcome is the mean time from randomization to complete delivery. Secondary outcomes include operative delivery, adverse neonatal outcomes, maternal adverse events and discomfort. This trial will establish whether upright posture and/or a controlled method of applying fundal pressure (GAP) can improve labour outcomes for women and their babies. If fundal pressure is found to have a measurable

The differences in postural reactions between scoliosis and scoliotic posture

Directory of Open Access Journals (Sweden)

Jacek Wilczyński

2017-05-01

Full Text Available The aim of the research was to demonstrate the differences in amplitudes of postural reactions in girls with scoliotic posture and idiopathic scoliosis. 28 girls aged 7-18 years old were involved in the study. Children attended to the Interschool Centre of Corrective Exercises in Starachowice. The research was conducted in June 2011. Spine research was made by Exhibeon digital radiography. Based on the size of the angle of spinal curvature there were identified: scoliotic posture: 1-9° and scoliosis: ≥10°. Postural reactions were examined by static-dynamic Tecnobody’s ST 310 Plus Stability System platform. There were 21 (75% children with scoliotic posture, and 7 (25% with idiopathic scoliosis. Student's t-test showed a significantly higher postural reactions for scoliosis in relation to scoliotic postures in case of: Average Forward-Backward Speed (OE, (p=0,05, Medium-Lateral Standard Deviation X (CE, (p=0,002, and Ellipse area (CE, (p=0,012. To verify the significant differences, demonstrating the lack of homogeneity of variance, the Mann–Whitney U-test has been used, which showed a significant differences between the scoliotic posture and scoliosis in case of: Medium-Lateral Standard Deviation X (CE, (p=0,0012, Average Forward-Backward Speed (OE, (p=0,0548, and Ellipse area (CE (p=0,0047. Together with an increase of the angle of curvature, the value of these postural reactions also grew. Most of postural reactions didn’t fit the norm.

Supine versus upright anterior images: comparison in T1-201 myocardial scintigraphy

International Nuclear Information System (INIS)

Jacobson, A.F.; Parker, J.A.; Royal, H.D.; Silverman, K.J.; Gervino, E.V.; Kolodny, G.M.

1987-01-01

In patients undergoing exercise thallium-201 myocardial scintigraphy, activity in the inferior wall on anterior images may appear diminished when the standard supine view is used, but normal when the view is acquired with the patient upright. To determine the clinical significance of this observation, the distribution of thallium-201 activity was semiquantitatively assessed in supine and upright anterior images obtained immediately after exercise in 93 patients (65 men, 28 women). The presence of inferior wall and coronary artery disease was established with coronary angiography or from documentation of previous myocardial infarction. Supine and upright images were compared with use of receiver operating characteristic curves. In male patients diagnostic accuracy for identification of both inferior wall and coronary artery disease was improved through the use of the upright anterior image. In women, there was no significant difference in reader performance with upright and supine images. Upright anterior images should be routinely obtained in men in order to reduce the frequency of false-positive identification of inferior wall defects

Intermittent use of an "anchor system" improves postural control in healthy older adults.

Science.gov (United States)

Freitas, Milena de Bem Zavanella; Mauerberg-deCastro, Eliane; Moraes, Renato

2013-07-01

Haptic information, provided by a non-rigid tool (i.e., an "anchor system"), can reduce body sway in individuals who perform a standing postural task. However, it was not known whether or not continuous use of the anchor system would improve postural control after its removal. Additionally, it was unclear as to whether or not frequency of use of the anchor system is related to improved control in older adults. The present study evaluated the effect of the prolonged use of the anchor system on postural control in healthy older individuals, at different frequencies of use, while they performed a postural control task (semi-tandem position). Participants were divided into three groups according to the frequency of the anchor system's use (0%, 50%, and 100%). Pre-practice phase (without anchor) was followed by a practice phase (they used the anchor system at the predefined frequency), and a post-practice phase (immediate and late-without anchor). All three groups showed a persistent effect 15min after the end of the practice phase (immediate post-practice phase). However, only the 50% group showed a persistent effect in the late post-practice phase (24h after finishing the practice phase). Older adults can improve their postural control by practicing the standing postural task, and use of the anchor system limited to half of their practice time can provide additional improvement in their postural control. Copyright © 2013 Elsevier B.V. All rights reserved.

Does increased postural threat lead to more conscious control of posture?

Science.gov (United States)

Huffman, J L; Horslen, B C; Carpenter, M G; Adkin, A L

2009-11-01

Although it is well established that postural threat modifies postural control, little is known regarding the underlying mechanism(s) responsible for these changes. It is possible that changes in postural control under conditions of elevated postural threat result from a shift to a more conscious control of posture. The purpose of this study was to determine the influence of elevated postural threat on conscious control of posture and to determine the relationship between conscious control and postural control measures. Forty-eight healthy young adults stood on a force plate at two different surface heights: ground level (LOW) and 3.2-m above ground level (HIGH). Centre of pressure measures calculated in the anterior-posterior (AP) direction were mean position (AP-MP), root mean square (AP-RMS) and mean power frequency (AP-MPF). A modified state-specific version of the Movement Specific Reinvestment Scale was used to measure conscious motor processing (CMP) and movement self-consciousness (MSC). Balance confidence, fear of falling, perceived stability, and perceived and actual anxiety indicators were also collected. A significant effect of postural threat was found for movement reinvestment as participants reported more conscious control and a greater concern about their posture at the HIGH height. Significant correlations between CMP and MSC with AP-MP were observed as participants who consciously controlled and were more concerned for their posture leaned further away from the platform edge. It is possible that changes in movement reinvestment can influence specific aspects of posture (leaning) but other aspects may be immune to these changes (amplitude and frequency).

Adult phantoms as function of body mass, height and posture by using caucasian anthropomorphic statistics; Fantomas adultos em funcao da massa corporal, da altura e da postura usando estatisticas antropometricas caucasianas

Energy Technology Data Exchange (ETDEWEB)

Kramer, Richard; Cassola, Vagner Ferreira; Lira, Carlos Alberto Brayner de Oliveira; Khoury, Helen Jamil, E-mail: rkramer@uol.com.b, E-mail: vagner.cassola@gmail.co [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear; Milian, Felix Mas, E-mail: felix_mas_milian@yahoo.co [Universidade Estadual de Santa Cruz (UESC), Ilheus, BA (Brazil). Dept. de Ciencias Exatas e Tecnologia

2011-10-26

The CALLDose{sub X} 4.0 computer program uses conversion coefficients for the MASH and FASH adult phantoms on the vertical and supine postures, representing the standard man and woman according to ICRP 90 and are called 'basic phantoms'. For improving the representation of real patients in the CALLDose{sub X}, this paper developed adults phantoms as function of mass and height by using anthropometric data from nine of them prevailing caucasian countries

Determining postural stability

Science.gov (United States)

Lieberman, Erez (Inventor); Forth, Katharine E. (Inventor); Paloski, William H. (Inventor)

2011-01-01

A method for determining postural stability of a person can include acquiring a plurality of pressure data points over a period of time from at least one pressure sensor. The method can also include the step of identifying a postural state for each pressure data point to generate a plurality of postural states. The method can include the step of determining a postural state of the person at a point in time based on at least the plurality of postural states.

Influence of Posture and Frequency Modes in Total Body Water Estimation Using Bioelectrical Impedance Spectroscopy in Boys and Adult Males

Directory of Open Access Journals (Sweden)

Masaharu Kagawa

2014-05-01

Full Text Available The aim of the study was to examine differences in total body water (TBW measured using single-frequency (SF and multi-frequency (MF modes of bioelectrical impedance spectroscopy (BIS in children and adults measured in different postures using the deuterium (2H dilution technique as the reference. Twenty-three boys and 26 adult males underwent assessment of TBW using the dilution technique and BIS measured in supine and standing positions using two frequencies of the SF mode (50 kHz and 100 kHz and the MF mode. While TBW estimated from the MF mode was comparable, extra-cellular fluid (ECF and intra-cellular fluid (ICF values differed significantly (p < 0.01 between the different postures in both groups. In addition, while estimated TBW in adult males using the MF mode was significantly (p < 0.01 greater than the result from the dilution technique, TBW estimated using the SF mode and prediction equation was significantly (p < 0.01 lower in boys. Measurement posture may not affect estimation of TBW in boys and adult males, however, body fluid shifts may still occur. In addition, technical factors, including selection of prediction equation, may be important when TBW is estimated from measured impedance.

Contractive relaxation systems and interacting particles for scalar conservation laws

International Nuclear Information System (INIS)

Katsoulakis, M.A.; Tzavaras, A.E.

1996-01-01

We consider a class of semi linear hyperbolic systems with relaxation that are contractive in the L 1 -norm and admit invariant regions. We show that, as the relaxation parameter ξ goes to zero, their solutions converge to a weak solution of the scalar multidimensional conversation law that satisfies the Kruzhkov conditions. In the case of one space dimension, we propose certain interacting particle systems, whose mesoscopic limit is the systems with relaxation and their macroscopic dynamics is described by entropy solutions of a scalar conservation law. (author)

Effect of scanning in the supine and prone positions on dilation of air-charged colon in CTVC

International Nuclear Information System (INIS)

Ye Jing; Chen Junkun; Zhang Zongjun; Wang Junpeng; Gao Dazhi

2003-01-01

Objective: To evaluate the effect of scanning in the supine and prone positions on dilation of air-charged colon in CT virtual colonoscopy (CTVC). Methods: Thirty cases underwent CTVC scanning in both the supine and prone positions immediately before colonoscopy, and the dilation of each intestine was graded. The differences of colon dilation in different positions were compared. Results: In supine and prone position, there were 26 (17.3%) and 22 (14.7%) insufficient dilating colon segments, respectively, and only 5 (3.3%) insufficient dilating colon segments in double positions. 15(50.0%) and 13(43.3%) colons dilated insufficiently in supine and prone position, respectively, and decreased to 5 (16.7%) in double positions. The dilation of rectum, sigmoid colon, and transverse colon had significant difference in different positions. Conclusion: When performing CTVC, it is highly necessary to scan in both the supine and prone positions in order to ensure the sufficient dilation of colon. In supine position, the dilation of transverse colon is better, while the dilation of rectum and sigmoid colon in prone position is superior to that in supine position

Supine or prone position for mini-PNL procedure: does it matter.

Science.gov (United States)

Tokatlı, Zafer; Gokce, Mehmet Ilker; Süer, Evren; Sağlam, Remzi

2015-06-01

In this study it is aimed to compare the success and complication rates of mini-PNL procedure in supine and prone positions. In this retrospective study data of 180 patients treated with MPNL either in supine (n = 54) or prone (n = 126) positions between May 2009 and August 2014 was investigated. Success was defined as no visible stones >2 mm. Perioperative complications were classified using the modified Clavien system. Groups were compared with Chi square test or Student t test and for statistical significance p value of 0.05 was accepted. Mean age of the population was 42.5 ± 8.2 years and mean stone size was 23.9 ± 4.1 mm. The two groups were similar with regard to demographic characteristics and stone related characteristics except the ASA status. Success rates of the supine and prone groups were 85.1 and 87.3%, respectively (p = 0.701). No statistically significant differences in terms of complications were observed. Mean operative time was the only parameter different between the two groups (55 vs 82 min, p = 0.001). Supine position for PNL seems to be promising and the complication and success rates are shown to be similar to the prone position with MPNL technique. The only significant benefit of this technique is shorter operative time.

Proximal supination osteotomy of the first metatarsal for hallux valgus.

Science.gov (United States)

Yasuda, Toshito; Okuda, Ryuzo; Jotoku, Tsuyoshi; Shima, Hiroaki; Hida, Takashi; Neo, Masashi

2015-06-01

Risk factors for hallux valgus recurrence include postoperative round-shaped lateral edge of the first metatarsal head and postoperative incomplete reduction of the sesamoids. To prevent the occurrence of such conditions, we developed a proximal supination osteotomy of the first metatarsal. Our aim was to describe this novel technique and report the outcomes in this report. Sixty-six patients (83 feet) underwent a distal soft tissue procedure combined with a proximal supination osteotomy. After the proximal crescentic osteotomy, the proximal fragment was pushed medially, and the distal fragment was abducted, and then the distal fragment of the first metatarsal was manually supinated. Outcomes were assessed using the American Orthopaedic Foot & Ankle Society (AOFAS) score and radiographic examinations. The average follow-up duration was 34 (range, 25 to 52) months. The mean AOFAS score improved significantly from 58.0 points preoperatively to 93.8 points postoperatively (P hallux valgus and intermetatarsal angle decreased significantly from 38.6 and 18.0 degrees preoperatively to 11.0 and 7.9 degrees postoperatively, respectively (both, P hallux valgus, defined as a hallux valgus angle ≥ 25 degrees. The rates of occurrence of a positive round sign and incomplete reduction of the sesamoids significantly decreased postoperatively, which may have contributed to the low hallux valgus recurrence rates. We conclude that a proximal supination osteotomy was an effective procedure for correction of hallux valgus and can achieve a low rate of hallux valgus recurrence. Level IV, retrospective case series. © The Author(s) 2015.

The Effects of Multisensory Balance Training on Postural Control in Older Adults

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Farnoosh Shams

2011-10-01

Full Text Available Objectives: It has been found that older adults fall or sway significantly more than younger ones under sensory conflict conditions. Considering the prospects of future increases in the elderly population size of Iran and the lack of proper postural control and the high costs of its probable consequences, this study investigated the effects of multi balance training on postural control. Methods & Materials: In this semi-experimental study, 34 elderly women participated in two training and control groups with the mean ages of 72.4 and 72.9 respectively. Before and after training, to investigate the functional balance and postural control, the Berg Balance Scale and a force plate were used. The training group participated in multisensory balance training sessions of 1 hour classes held three days per week for five weeks. Data was analyzed using an independent sample and a paired t-test. Results: The analysis showed significant differences between the training group and the control after balance training in the measured parameters of postural control consisting of path length and mean velocity in the eyes open (P=0.001 and eyes closed (P=0.0001 conditions and the Berg Balance Scale (P=0.002. Conclusion: Results indicate that multisensory balance training can improve the parameters of postural control even in short term.

Effect of supine exercise on platelet aggregation and fibrinolytic activity

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Dag, B; Fornitz, Gitte Gleerup; Bak, A M

1994-01-01

In 12 healthy young men, strenuous cycling exercise in the supine position, caused platelet aggregability to decrease and the ADP threshold to rise from 7.0 microM resting, to 9.5 exercising (P ... from 178 to 68 min, PAI-1 fell from 8.91 to 5.16 IU ml-1, and t-PA rose from 0.56 to 3.95 IU ml-1, all three values were significant to P exercise, it did not increase platelet activity as expected, but caused a modest increase...... of fibrinolytic activity. These results suggest that supine exercise will not affect the haemostatic system adversely....

Setup accuracy for prone and supine whole breast irradiation

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Mulliez, Thomas; Vercauteren, Tom; Greveling, Annick van; Speleers, Bruno; Neve, Wilfried de; Veldeman, Liv [University Hospital Ghent, Department of Radiotherapy, Ghent (Belgium); Gulyban, Akos [University Hospital Ghent, Department of Radiotherapy, Ghent (Belgium); University Hospital Liege, Department of Radiotherapy, Liege (Belgium)

2016-04-15

To evaluate cone-beam computed tomography (CBCT) based setup accuracy and margins for prone and supine whole breast irradiation (WBI). Setup accuracy was evaluated on 3559 CBCT scans of 242 patients treated with WBI and uncertainty margins were calculated using the van Herk formula. Uni- and multivariate analysis on individual margins was performed for age, body mass index (BMI) and cup size. The population-based margin in vertical (VE), lateral (LA) and longitudinal (LO) directions was 10.4/9.4/9.4 mm for the 103 supine and 10.5/22.4/13.7 mm for the 139 prone treated patients, being significantly (p < 0.01) different for the LA and LO directions. Multivariate analysis identified a significant (p < 0.05) correlation between BMI and the LO margin in supine position and the VE/LA margin in prone position. In this series, setup accuracy is significantly worse in prone compared to supine position for the LA and LO directions. However, without proper image-guidance, uncertainty margins of about 1 cm are also necessary for supine WBI. For patients with a higher BMI, larger margins are required. (orig.) [German] Ziel der Arbeit war es, die interfraktionelle Repositionierungsgenauigkeit in Bauchlage (BL) versus Rueckenlage (RL) bei Ganzbrustbestrahlung (GBB) mittels Cone-Beam-CT (CBCT) zu bestimmen, um die notwendigen PTV-Sicherheitsabstaende zu definieren. Die Repositionierungsgenauigkeit wurde basierend an 3559 CBCT-Scans von 242 mit GBB behandelten Patienten ausgewertet. Die PTV-Sicherheitsabstaende wurden unter Verwendung der ''van-Herk''-Formel berechnet. Uni- und multivariable Analysen wurden fuer Sicherheitsabstaende in jede Richtung auf Basis von Alter, Body-Mass-Index (BMI) und Koerbchengroesse durchgefuehrt. Die basierend auf den taeglichen CBCT-Verschiebungen berechneten PTV-Sicherheitsabstaende betrugen in anteroposteriorer (AP), lateraler (LT oder links-rechts) und kraniokaudaler (CC) Richtung 10,4/9,4/9,4 mm fuer die RL (103 Patienten) und

Body posture and postural stability of people practicing qigong

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Jacek Wilczyński

2015-07-01

Full Text Available Introduction: Correct and stable posture is essential for the implementation of the majority of voluntary movements and locomotion. The study of postural stability is an element of clinical trials evaluating physical activity in order to determine the optimal therapeutic procedures. Qigong exercises are not only a form of prevention, helpful in maintaining wellbeing, but also a means of therapy in many diseases, including disorders of postural stability. Aim of the research: To analyse the association between the quality of posture and postural stability of people practicing qigong. Material and methods : The study involved 32 people. The mean age of those tested was 54 years. Posture study used optoelectronic method Diers formetric III 4D. Postural stability was tested on the platform Biodex Balance System. The studies were performed at the Posture Laboratory of the Institute of Physiotherapy at Jan Kochanowski University in Kielce. Results and conclusions : Spearman rank order correlation showed a positive correlation of relative rotation of the spine area with a general indicator of stability (p = 0.0206 at an average level (R = 0.4075 and with the index of the stability A/P (p = 0.0310, although at a lower level (R = 0.3819. With the increase in the relative rotation of the spine area the overall stability indicator and stability indicator A/P also increased. Significant positive correlations were also seen for the surface rotation (+max and a general indication of the stability and the stability index A/P. With the increase of surface rotation (+max of the spine the overall stability indicator and stability indicator A/P also increased.

Effects of supine, prone, and lateral positions on cardiovascular and renal variables in humans

DEFF Research Database (Denmark)

Pump, Bettina; Talleruphuus, Ulrik; Christensen, Niels Juel

2002-01-01

The hypothesis was tested that changing the direction of the transverse gravitational stress in horizontal humans modulates cardiovascular and renal variables. On different study days, 14 healthy males were placed for 6 h in either the horizontal supine or prone position following 3 h of being...... supine. Eight of the subjects were in addition investigated in the horizontal left lateral position. Compared with supine, the prone position slightly increased free water clearance (349 +/- 38 vs. 447 +/- 39 ml/6 h, P = 0.05) and urine output (1,387 +/- 55 vs. 1,533 +/- 52 ml/6 h, P = 0...

Modified supine versus prone percutaneous nephrolithotomy: Surgical outcomes from a tertiary teaching hospital

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Madeleine Nina Jones

2016-07-01

Full Text Available Purpose: The traditional prone positioning of percutaneous nephrolithotomy (PCNL is associated with various anesthetic and logistic difficulties. We aimed to compare the surgical outcomes of PCNLs performed using our modified supine position with those performed in the standard prone position. Materials and Methods: A prospective group of 236 renal units (224 patients undergoing PCNL were included in this 2 site study: 160 were performed in the modified supine position were compared with 76 undergoing PCNL in the prone position. The outcomes of radiation dose, radiation time, stone free rate, body mass index (BMI, stone size, operative time, length of stay (LOS, in hospital and complications were compared. Chi-square and t-tests were used. Results: There were no significant differences in mean radiation time, radiation dose or stone size between the modified supine and prone groups. The supine group had a higher mean BMI (31 kg/m2 vs. 28 kg/m2 , p=0.03, shorter mean surgical time (93 minutes vs. 123 minutes, p<0.001, shorter mean LOS (2 days vs. 3 days, p=0.005 and higher stone free rate (70% vs. 50%, p=0.005. There were no differences in septic or bleeding complications but the prone group had a higher rate of overall complications. Conclusions: Modified supine PCNL has significantly lower operative time, shorter LOS and higher stone-free rate compared with prone in our series, while remaining a safe procedure.

Using impedance cardiography with postural change to stratify patients with hypertension.

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DeMarzo, Arthur P

2011-06-01

Early detection of cardiovascular disease in patients with hypertension could initiate appropriate treatment to control blood pressure and prevent the progression of cardiovascular disease. The goal of this study was to show how impedance cardiography waveform analysis with postural change can be used to detect subclinical cardiovascular disease in patients with high blood pressure. Patients with high blood pressure had impedance cardiography data obtained in two positions, standing upright and supine. In 50 adults, impedance cardiography indicated that all patients had abnormal data, with 44 (88%) having multiple abnormalities. Impedance cardiography showed 32 (64%) had ventricular dysfunction, 48 (96%) had vascular load abnormalities, 34 (68%) had hemodynamic abnormalities, 2 (4%) had hypovolemia, and 3 (6%) had hypervolemia. Hypertensive patients have diverse cardiovascular abnormalities that can be quantified by impedance cardiography. By stratifying patients with ventricular, vascular, and hemodynamic abnormalities, treatment could be customized based on the abnormal underlying mechanisms with the potential to rapidly control blood pressure, prevent progression of cardiovascular disease, and possibly reverse remodeling.

Dosimetric effects of the prone and supine positions on image guided localized prostate cancer radiotherapy

International Nuclear Information System (INIS)

Liu Bei; Lerma, Fritz A.; Patel, Shilpen; Amin, Pradip; Feng Yuanming; Yi, B.-Y.; Yu, Cedric

2008-01-01

Purpose: To compare target coverage and doses to rectum and bladder in IMRT of localized prostate cancer in the supine versus prone position, with the inclusion of image guidance. Materials and methods: Twenty patients with early stage localized prostate carcinoma who received external beam radiotherapy in the supine and prone positions underwent approximately 10 serial CT examinations in their respective treatment position in non-consecutive days, except for one patient who was treated prone but serially imaged supine. The prostate, bladder and rectum were contoured on all CT scans. A PTV was generated on the first scan of each patient's CT series by expanding the prostate with a 5 mm margin and an IMRT plan was created. The resultant IMRT plan was then applied to that patient's remaining serial CT scans by aligning the initial CT image set with the subsequent serial CT image sets using (1) skin marks, (2) bony anatomy and (3) center of mass of the prostate. The dosimetric results from these three alignments were compared between the supine and prone groups. To account for the uncertainties associated with prostate delineation and intra-fractional geometric changes, a fictional 'daily PTV' was generated by expanding the prostate with a 3 mm margin on each serial CT scan. Thus, a more realistic target coverage index, V95, was quantified as the fraction of the daily PTV receiving at least 95% of the prescription dose. Dose-volume measures of the organs at risk were also compared. The fraction of the daily PTV contained by the initial PTV after each alignment method was quantified on each patient's serial CT scan, and is defined as PTV overlap index. Results: As expected, alignment based on skin marks yielded unacceptable dose coverage for both groups of patients. Under bony alignment, the target coverage index, V95, was 97.3% and 93.6% for prone and supine patients (p < 0.0001), respectively. The mean PTV overlap indices were 90.7% and 84.7% for prone and supine

Trunk muscle activity during different variations of the supine plank exercise

DEFF Research Database (Denmark)

Calatayud, Joaquin; Casaña, Jose; Martín, Fernando

2017-01-01

Background Exercises providing neuromuscular challenges of the spinal muscles are desired for core stability, which is important for workers with heavy manual labour as well as people recovering from back pain. Purpose This study evaluated whether using a suspended modality increases trunk muscle...... voluntary isometric contraction (MVIC). Results No differences between exercises were found for UP ABS, LOW ABS and OBLIQ muscle activity. The unilateral suspended supine plank provided the highest LUMB activity (20% of MVIC) whiles the bilateral stable supine plank provided the lowest activity (11% of MVIC...

Interactions between posture and locomotion: motor patterns in humans walking with bent posture versus erect posture.

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Grasso, R; Zago, M; Lacquaniti, F

2000-01-01

Human erect locomotion is unique among living primates. Evolution selected specific biomechanical features that make human locomotion mechanically efficient. These features are matched by the motor patterns generated in the CNS. What happens when humans walk with bent postures? Are normal motor patterns of erect locomotion maintained or completely reorganized? Five healthy volunteers walked straight and forward at different speeds in three different postures (regular, knee-flexed, and knee- and trunk-flexed) while their motion, ground reaction forces, and electromyographic (EMG) activity were recorded. The three postures imply large differences in the position of the center of body mass relative to the body segments. The elevation angles of the trunk, pelvis, and lower limb segments relative to the vertical in the sagittal plane, the ground reaction forces and the rectified EMGs were analyzed over the gait cycle. The waveforms of the elevation angles along the gait cycle remained essentially unchanged irrespective of the adopted postures. The first two harmonics of these kinematic waveforms explain >95% of their variance. The phase shift but not the amplitude ratio between the first harmonic of the elevation angle waveforms of adjacent pairs was affected systematically by changes in posture. Thigh, shank, and foot angles covaried close to a plane in all conditions, but the plane orientation was systematically different in bent versus erect locomotion. This was explained by the changes in the temporal coupling among the three segments. For walking speeds >1 m s(-1), the plane orientation of bent locomotion indicates a much lower mechanical efficiency relative to erect locomotion. Ground reaction forces differed prominently in bent versus erect posture displaying characteristics intermediate between those typical of walking and those of running. Mean EMG activity was greater in bent postures for all recorded muscles independent of the functional role. The waveforms

Biceps brachii can add to performance of tasks requiring supination in cerebral palsy patients

NARCIS (Netherlands)

de Bruin, M.; Veeger, H.E.J.; Kreulen, M.; Smeulders, M.J.C.; Bus, S.A.

2013-01-01

The aim of this study was to assess whether cerebral palsy patients can use biceps brachii for supination during movement tasks requiring supination and pronation. 3D upper extremity kinematic and EMG-data of 12 patients (mean age 13. y 8. mo. ±. 36. mo) were compared to 10 healthy age-matched

Biceps brachii can add to performance of tasks requiring supination in cerebral palsy patients

NARCIS (Netherlands)

de Bruin, M.; Veeger, H. E. J.; Kreulen, M.; Smeulders, M. J. C.; Bus, S. A.

2013-01-01

The aim of this study was to assess whether cerebral palsy patients can use biceps brachii for supination during movement tasks requiring supination and pronation. 3D upper extremity kinematic and EMG-data of 12 patients (mean age 13 y 8 mo ± 36 mo) were compared to 10 healthy age-matched controls.

Catecholamine responses to changes in posture during human pregnancy.

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Whittaker, P G; Gerrard, J; Lind, T

1985-06-01

Human pregnancy may induce changes in the sensitivity of the cardiovascular system to endogenous catecholamines. This was investigated in multigravid women with little likelihood of unsuspected vascular disease. The responses of blood pressure, pulse rate, plasma noradrenaline and adrenaline to a change in posture from semi-recumbency to standing were assessed in six normotensive women at 36 weeks gestation and in six non-pregnant control subjects. Standing for 10 min caused a surge in blood pressure, pulse rate and plasma noradrenaline in non-pregnant women. The pregnant women, whose basal levels of noradrenaline were higher than those in non-pregnant women, showed a slower noradrenergic response to postural change, and this response had less effect upon the cardiovascular indices. Blood pressure dropped immediately on standing and pulse rate remained unaffected throughout. It is suggested that some women may maintain a non-pregnant level of pressor sensitivity during pregnancy and thereby become hypertensive.

Comparison of the kidney dose between supine and prone position for pelvic and periaortic irradiation

International Nuclear Information System (INIS)

Mison, Chun; Haejin, Kang; Juree, Kim; Heesuk, Ryu; Hyunsoo, Shin

1996-01-01

We compared the doses received by the kidney in supine and prone positions for pelvic and periaortic irradiation. Kidney locations were verified by CT images taken with patients in the same position as during the treatment. Due to the shift of the kidney anteriorly during prone position, treatment in supine position delivered a much lower dose to most of the kidney than treatment in the prone position. Therefore, for periaortic irradiation treatment, the supine position should be considered to minimize the dose to the kidneys, even though the prone position with a belly board can reduce the dose to the small bowel

Variations in rest vertical dimension: effects of standing posture in edentulous patients.

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Makzoume, Joseph E

2007-01-01

The orientation of a patient's head changes, depending on whether he or she is sitting or standing in a relaxed upright position. An edentulous patient's vertical dimension at rest may show variations that can result in an inaccurate determination of his or her occlusal vertical dimension. This study recorded the rest vertical dimension (RVD) established among 60 totally edentulous subjects who were standing in the position of greatest comfort (self-balance position) and compared it with the patients' RVD when they were seated in a relaxed upright position, with the Frankfort Plane parallel to the horizontal. The RVD was measured (in mm) between two dots located on the midline of the face. Two measurements were made: one when the patient was seated upright and relaxed (with the Frankfort Plane parallel to the horizontal) with no head support, and the other when the patient was standing relaxed on both feet in a self-balance position. Five alternated measurements were made for each subject in each position. A mean RVD was calculated for each subject in each body posture and the mean values from both positions were compared. Statistical analysis was performed using Student's t-test (alpha = 0.05). No significant differences were noted between the RVD of the seated and standing positions (P = 0.67).

Objective Sleep Assessments in Patients with Postural Tachycardia Syndrome using Overnight Polysomnograms

Science.gov (United States)

Bagai, Kanika; Peltier, Amanda C.; Malow, Beth A.; Diedrich, André; Shibao, Cyndya A.; Black, Bonnie K.; Paranjape, Sachin Y.; Orozco, Carlos; Biaggioni, Italo; Robertson, David; Raj, Satish R.

2016-01-01

Study Objectives: Patients with postural tachycardia syndrome (POTS) commonly complain of fatigue, unrefreshing sleep, daytime sleepiness, and diminished quality of life. The study objective was to assess objective sleep quality in POTS patients using overnight polysomnography. Methods: We studied 16 patients with POTS and 15 healthy control subjects performing daytime autonomic functions tests and overnight polysomnography at the Vanderbilt Clinical Research Center. Results: There were no significant differences in the objective sleep parameters including sleep efficiency, sleep onset latency, wake time after sleep onset, REM latency, percentage of time spent in N1, N2, N3, and REM sleep, arousal index, apnea-hypopnea index, or periodic leg movement index in POTS patients as compared with healthy control subjects. There were significant negative correlations between sleep efficiency and the change in HR from supine to stand (rs = −0.527; p = 0.036) Conclusions: POTS patients do not have significant differences in objective sleep parameters as compared to control subjects based on overnight polysomnograms. Activation of the sympathetic nervous system may contribute significantly to the hyper arousal state and worsening of subjective estimates of sleep quality as previously reported in POTS patients. Citation: Bagai K, Peltier AC, Malow BA, Diedrich A, Shibao CA, Black BK, Paranjape SY, Orozco C, Biaggioni I, Robertson D, Raj SR. Objective sleep assessments in patients with postural tachycardia syndrome using overnight polysomnograms. J Clin Sleep Med 2016;12(5):727–733. PMID:26951415

Postural orientation and equilibrium processes associated with increased postural sway in autism spectrum disorder (ASD).

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Wang, Zheng; Hallac, Rami R; Conroy, Kaitlin C; White, Stormi P; Kane, Alex A; Collinsworth, Amy L; Sweeney, John A; Mosconi, Matthew W

2016-01-01

Increased postural sway has been repeatedly documented in children with autism spectrum disorder (ASD). Characterizing the control processes underlying this deficit, including postural orientation and equilibrium, may provide key insights into neurophysiological mechanisms associated with ASD. Postural orientation refers to children's ability to actively align their trunk and head with respect to their base of support, while postural equilibrium is an active process whereby children coordinate ankle dorsi-/plantar-flexion and hip abduction/adduction movements to stabilize their upper body. Dynamic engagement of each of these control processes is important for maintaining postural stability, though neither postural orientation nor equilibrium has been studied in ASD. Twenty-two children with ASD and 21 age and performance IQ-matched typically developing (TD) controls completed three standing tests. During static stance, participants were instructed to stand as still as possible. During dynamic stances, participants swayed at a comfortable speed and magnitude in either anterior-posterior (AP) or mediolateral (ML) directions. The center of pressure (COP) standard deviation and trajectory length were examined to determine if children with ASD showed increased postural sway. Postural orientation was assessed using a novel virtual time-to-contact (VTC) approach that characterized spatiotemporal dimensions of children's postural sway (i.e., body alignment) relative to their postural limitation boundary, defined as the maximum extent to which each child could sway in each direction. Postural equilibrium was quantified by evaluating the amount of shared or mutual information of COP time series measured along the AP and ML directions. Consistent with prior studies, children with ASD showed increased postural sway during both static and dynamic stances relative to TD children. In regard to postural orientation processes, children with ASD demonstrated reduced spatial

Body posture modulates action perception.

Science.gov (United States)

Zimmermann, Marius; Toni, Ivan; de Lange, Floris P

2013-04-03

Recent studies have highlighted cognitive and neural similarities between planning and perceiving actions. Given that action planning involves a simulation of potential action plans that depends on the actor's body posture, we reasoned that perceiving actions may also be influenced by one's body posture. Here, we test whether and how this influence occurs by measuring behavioral and cerebral (fMRI) responses in human participants predicting goals of observed actions, while manipulating postural congruency between their own body posture and postures of the observed agents. Behaviorally, predicting action goals is facilitated when the body posture of the observer matches the posture achieved by the observed agent at the end of his action (action's goal posture). Cerebrally, this perceptual postural congruency effect modulates activity in a portion of the left intraparietal sulcus that has previously been shown to be involved in updating neural representations of one's own limb posture during action planning. This intraparietal area showed stronger responses when the goal posture of the observed action did not match the current body posture of the observer. These results add two novel elements to the notion that perceiving actions relies on the same predictive mechanism as planning actions. First, the predictions implemented by this mechanism are based on the current physical configuration of the body. Second, during both action planning and action observation, these predictions pertain to the goal state of the action.

Supraesophageal Reflux: Correlation of Position and Occurrence of Acid Reflux-Effect of Head-of-Bed Elevation on Supine Reflux.

Science.gov (United States)

Scott, David R; Simon, Ronald A

2015-01-01

Supraesophageal reflux of gastric contents can contribute to perennial nasopharyngitis, cough, and asthma. However, effective treatment strategies for supraesophageal reflux disease (SERD) remain inadequately defined. The purpose of this study is to assess the prevalence and timing of SERD and to investigate the efficacy of head-of-bed elevation in its treatment. A retrospective chart review of patients seen at Scripps Clinic Division of Allergy, Asthma and Immunology was performed who had undergone overnight nasopharyngeal pH monitoring with a commercially available nasopharyngeal pH-monitoring device, Dx-pH Measurement System from Restech, San Diego, Calif. Subjects with reflux were classified based on the position of reflux as either supine only, upright only, or both supine and upright. In a subset of subjects with supine-only reflux, pH monitoring was compared before and after elevating the head of bed 6 inches. Adequate nasopharyngeal pH-monitoring data were obtained for 235 patients. Reflux was detected in 113 (48%) patients. The pattern of reflux observed was 62 (55%) supine only, 4 (4%) upright only, and 47 (42%) upright and supine. Sequential overnight nasopharyngeal pH monitoring before and after head-of-bed elevation was obtained in 13 individuals with supine-only reflux. Ten subjects demonstrated significant improvement, 8 of whom demonstrated complete resolution of supine reflux with 6 inches of head-of-bed elevation. This study provides new evidence that SERD frequently occurs in the supine position and that 6 inches of head-of-bed elevation is effective in reducing supine SERD. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Two stages and three components of the postural preparation to action.

Science.gov (United States)

Krishnan, Vennila; Aruin, Alexander S; Latash, Mark L

2011-07-01

Previous studies of postural preparation to action/perturbation have primarily focused on anticipatory postural adjustments (APAs), the changes in muscle activation levels resulting in the production of net forces and moments of force. We hypothesized that postural preparation to action consists of two stages: (1) Early postural adjustments (EPAs), seen a few hundred ms prior to an expected external perturbation and (2) APAs seen about 100 ms prior to the perturbation. We also hypothesized that each stage consists of three components, anticipatory synergy adjustments seen as changes in covariation of the magnitudes of commands to muscle groups (M-modes), changes in averaged across trials levels of muscle activation, and mechanical effects such as shifts of the center of pressure. Nine healthy participants were subjected to external perturbations created by a swinging pendulum while standing in a semi-squatting posture. Electrical activity of twelve trunk and leg muscles and displacements of the center of pressure were recorded and analyzed. Principal component analysis was used to identify four M-modes within the space of muscle activations using indices of integrated muscle activation. This analysis was performed twice, over two phases, 400-700 ms prior to the perturbation and over 200 ms just prior to the perturbation. Similar robust results were obtained using the data from both phases. An index of a multi-M-mode synergy stabilizing the center of pressure displacement was computed using the framework of the uncontrolled manifold hypothesis. The results showed high synergy indices during quiet stance. Each of the two stages started with a drop in the synergy index followed by a change in the averaged across trials activation levels in postural muscles. There was a very long electromechanical delay during the early postural adjustments and a much shorter delay during the APAs. Overall, the results support our main hypothesis on the two stages and three components

Postural control and functional balance in individuals with diabetic peripheral neuropathy

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Ana Claudia de Souza Fortaleza

2013-04-01

Full Text Available Diabetic Peripheral Neuropathy (DPN brings on reduced somatosensation, which can lead to changes in postural control. The objective of this study was to evaluate postural control in a standing position and in different conditions, as well as functional balance in individuals with DPN, make the correlation between the results obtained from the postural control assessment with the values from the functional balance test and compare the results obtained in the neuropathy group with those of the control group, checking for possible differences between the evaluation conditions of both groups. The study included 13 women with DPN (NG and 17 non-diabetic women (CG. Postural control assessment was performed by kinemetry in the following conditions: eyes opened (EO, eyes closed (EC, and semi-tandem (ST. The data was processed in MATLAB and the following variables were generated: mean amplitude of oscillation (MAO in the anterior-posterior (AP and medial-lateral (ML direction; and average speed of oscillation (ASO in AP and ML direction. Functional balance was assessed by the Timed Up and Go Test. There was significant difference between the groups (p≤0.005 in MAO-AP EO and EC, MAO-ML EC and ST, and ASO-ML ST. There were differences between the conditions EO and ST (p≤0.005 and EC and ST (p≤0.005 for the variables MAO-ML and ASO-ML with greater damage to the NG, which also had a lower functional balance (p=0.001. ML instability was positively correlated with functional imbalance. The results show a change in the postural control system in the DPN, which could lead these individuals to a higher risk for falls and functional impairment.

Relaxation approximations to second-order traffic flow models by high-resolution schemes

International Nuclear Information System (INIS)

Nikolos, I.K.; Delis, A.I.; Papageorgiou, M.

2015-01-01

A relaxation-type approximation of second-order non-equilibrium traffic models, written in conservation or balance law form, is considered. Using the relaxation approximation, the nonlinear equations are transformed to a semi-linear diagonilizable problem with linear characteristic variables and stiff source terms with the attractive feature that neither Riemann solvers nor characteristic decompositions are in need. In particular, it is only necessary to provide the flux and source term functions and an estimate of the characteristic speeds. To discretize the resulting relaxation system, high-resolution reconstructions in space are considered. Emphasis is given on a fifth-order WENO scheme and its performance. The computations reported demonstrate the simplicity and versatility of relaxation schemes as numerical solvers

Postural changes and pain in the academic performance of elementary school students

Directory of Open Access Journals (Sweden)

Maria Homéria Leite de Morais Sampaio

Full Text Available Abstract Postural changes and pain in the spine of children and adolescents of school age are influenced by the permanent incorrect sitting position, misuse of furniture and weight of the backpack. The aim of this study was to verify postural changes and pain in the academic performance of elementary school students. It was a cross-sectional study, with a descriptive and analytical approach. The subjects were 83 elementary students, aged 8 to 12 years, of Kindergarten and Elementary Education at Paulo Sarasate Municipal School, Ceará. It was performed from March to June 2008. In the physical examination it was used an evaluation form, based on Global Postural reeducation, by Souchard method, which included the variables: compromised anterior, posterior, superior shoulder muscle chains and pain and, in academic performance, a semi-structured questionnaire with the variables: behavior, attendance and performance. The data was stored in the Statistical Package for the Social Science (SPSS version 18.0. In the descriptive analysis, absolute and relative frequencies were used, and in the inferential analysis, the following tests were applied: Mann-Whitney, to verify the existence of significant differences in changes in groups A and B, at a significance level of 5%, and the F statistical test, for comparing postural changes and pain, in the three grades. Results: it was noted that the majority of the students presented postural changes, such as forward head, lifted shoulders, dorsal hyperkyphosis and pain, which predominantly occurred in the anterior chain, when compared with the posterior and superior chains. These changes in both groups were statistically significant only in subjects of the fifth grade with satisfactory academic performance and behavior. It was concluded that there was no association between postural changes and school performance, although it was influenced by pain.

Postural stability effects of random vibration at the feet of construction workers in simulated elevation.

Science.gov (United States)

Simeonov, P; Hsiao, H; Powers, J; Ammons, D; Kau, T; Amendola, A

2011-07-01

The risk of falls from height on a construction site increases under conditions which degrade workers' postural control. At elevation, workers depend heavily on sensory information from their feet to maintain balance. The study tested two hypotheses: "sensory enhancement"--sub-sensory (undetectable) random mechanical vibrations at the plantar surface of the feet can improve worker's balance at elevation; and "sensory suppression"--supra-sensory (detectable) random mechanical vibrations can have a degrading effect on balance in the same experimental settings. Six young (age 20-35) and six aging (age 45-60) construction workers were tested while standing in standard and semi-tandem postures on instrumented gel insoles. The insoles applied sub- or supra-sensory levels of random mechanical vibrations to the feet. The tests were conducted in a surround-screen virtual reality system, which simulated a narrow plank at elevation on a construction site. Upper body kinematics was assessed with a motion-measurement system. Postural stability effects were evaluated by conventional and statistical mechanics sway measures, as well as trunk angular displacement parameters. Analysis of variance did not confirm the "sensory enhancement" hypothesis, but provided evidence for the "sensory suppression" hypothesis. The supra-sensory vibration had a destabilizing effect, which was considerably stronger in the semi-tandem posture and affected most of the sway variables. Sensory suppression associated with elevated vibration levels on a construction site may increase the danger of losing balance. Construction workers at elevation, e.g., on a beam or narrow plank might be at increased risk of fall if they can detect vibrations under their feet. To reduce the possibility of losing balance, mechanical vibration to supporting structures used as walking/working surfaces should be minimized when performing construction tasks at elevation. Published by Elsevier Ltd.

Dynamic loop gain increases upon adopting the supine body position during sleep in patients with obstructive sleep apnoea.

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Joosten, Simon A; Landry, Shane A; Sands, Scott A; Terrill, Philip I; Mann, Dwayne; Andara, Christopher; Skuza, Elizabeth; Turton, Anthony; Berger, Philip; Hamilton, Garun S; Edwards, Bradley A

2017-11-01

Obstructive sleep apnoea (OSA) is typically worse in the supine versus lateral sleeping position. One potential factor driving this observation is a decrease in lung volume in the supine position which is expected by theory to increase a key OSA pathogenic factor: dynamic ventilatory control instability (i.e. loop gain). We aimed to quantify dynamic loop gain in OSA patients in the lateral and supine positions, and to explore the relationship between change in dynamic loop gain and change in lung volume with position. Data from 20 patients enrolled in previous studies on the effect of body position on OSA pathogenesis were retrospectively analysed. Dynamic loop gain was calculated from routinely collected polysomnographic signals using a previously validated mathematical model. Lung volumes were measured in the awake state with a nitrogen washout technique. Dynamic loop gain was significantly higher in the supine than in the lateral position (0.77 ± 0.15 vs 0.68 ± 0.14, P = 0.012). Supine functional residual capacity (FRC) was significantly lower than lateral FRC (81.0 ± 15.4% vs 87.3 ± 18.4% of the seated FRC, P = 0.021). The reduced FRC we observed on moving to the supine position was predicted by theory to increase loop gain by 10.2 (0.6, 17.1)%, a value similar to the observed increase of 8.4 (-1.5, 31.0)%. Dynamic loop gain increased by a small but statistically significant amount when moving from the lateral to supine position and this may, in part, contribute to the worsening of OSA in the supine sleeping position. © 2017 Asian Pacific Society of Respirology.

Evaluation of supine and sitting cardiac blood pool scans with sup(99m)Tc-HSA

International Nuclear Information System (INIS)

Bunko, Hisashi; Kuwajima, Akira; Hisada, Kinichi

1977-01-01

In the differential diagnosis of enlarged cardiac silhouette on plain chest x-ray film, cardiac blood pool scan was usually performed at first. However, small amount of pericardial effusion was difficult to detect on cardiac blood pool scan and differentiation of pericardial effusion from myocardial thickening was sometimes difficult. We evaluated cardiac blood pool scan with sup(99m)Tc-HSA(human serum albumin) and gamma camera imaged on both supine and sitting position, and evaluated diagnostic efficiency of criteria for pericardial effusion of these scans. Fifty-seven patients suspected of having pericardial effusion were included in the study. Sixteen of these patients had pericardial effusion and 2 of these 16 patients had free pleural effusion. Three patients had pleural effusion alone and excluded from the study. Of the five criteria for pericardial effusion, separation between heart and right lung activities was most frequent in both effusion (true positive, TP=100% on both supine and sitting) and no effusion (false positive, FP=18.4% on supine and 23.7% on sitting) groups. However, increased heart and right lung separation on sitting position was rather frequent in effusion group, and this finding was also thought to be typical for effusion but not for myocardial thickening. Decreased cardiohepatic separation on sitting position was frequent in no effusion group, and FP rate was decreased from 18.4% (supine) to 10.5% (sitting). Two patients with both pericardial effusion and free pleural effusion were easily diagnosed on sitting cardiac blood pool scan. With ROC(receiver operating characteristic) curve, three criteria should be agreed on either supine or sitting scan for diagnosis of pericardial effusion, and six criteria should be agreed when both supine and sitting scans were employed for diagnosis of pericardial effusion. (auth.)

Supine proton beam craniospinal radiotherapy using a novel tabletop adapter

International Nuclear Information System (INIS)

Buchsbaum, Jeffrey C.; Besemer, Abby; Simmons, Joseph; Hoene, Ted; Simoneaux, Victor; Sandefur, Amy; Wolanski, Mark; Li, Zhao; Cheng, Chee-Wei

2013-01-01

To develop a device that allows supine craniospinal proton and photon therapy to the vast majority of proton and photon facilities currently experiencing limitations as a result of couch design issues. Plywood and carbon fiber were used for the development of a prototype unit. Once this was found to be satisfactory after all design issues were addressed, computer-assisted design (CAD) was used and carbon fiber tables were built to our specifications at a local manufacturer of military and racing car carbon fiber parts. Clinic-driven design was done using real-time team discussion for a prototype design. A local machinist was able to construct a prototype unit for us in <2 weeks after the start of our project. Once the prototype had been used successfully for several months and all development issues were addressed, a custom carbon fiber design was developed in coordination with a carbon fiber manufacturer in partnership. CAD methods were used to design the units to allow oblique fields from head to thigh on patients up to 200 cm in height. Two custom-designed carbon fiber craniospinal tabletop designs now exist: one long and one short. Four are in successful use in our facility. Their weight tolerance is greater than that of our robot table joint (164 kg). The long unit allows for working with taller patients and can be converted into a short unit as needed. An affordable, practical means of doing supine craniospinal therapy with protons or photons can be used in most locations via the use of these devices. This is important because proton therapy provides a much lower integral dose than all other therapy methods for these patients and the supine position is easier for patients to tolerate and for anesthesia delivery. These units have been successfully used for adult and pediatric supine craniospinal therapy, proton therapy using oblique beams to the low pelvis, treatment of various spine tumors, and breast-sparing Hodgkin's therapy

Supine proton beam craniospinal radiotherapy using a novel tabletop adapter

Energy Technology Data Exchange (ETDEWEB)

Buchsbaum, Jeffrey C., E-mail: jbuchsba@iupui.edu [IU Health Proton Therapy Center, Bloomington, IN (United States); Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States); Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN (United States); Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN (United States); Besemer, Abby; Simmons, Joseph; Hoene, Ted; Simoneaux, Victor; Sandefur, Amy [IU Health Proton Therapy Center, Bloomington, IN (United States); Wolanski, Mark; Li, Zhao; Cheng, Chee-Wei [IU Health Proton Therapy Center, Bloomington, IN (United States); Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States)

2013-04-01

To develop a device that allows supine craniospinal proton and photon therapy to the vast majority of proton and photon facilities currently experiencing limitations as a result of couch design issues. Plywood and carbon fiber were used for the development of a prototype unit. Once this was found to be satisfactory after all design issues were addressed, computer-assisted design (CAD) was used and carbon fiber tables were built to our specifications at a local manufacturer of military and racing car carbon fiber parts. Clinic-driven design was done using real-time team discussion for a prototype design. A local machinist was able to construct a prototype unit for us in <2 weeks after the start of our project. Once the prototype had been used successfully for several months and all development issues were addressed, a custom carbon fiber design was developed in coordination with a carbon fiber manufacturer in partnership. CAD methods were used to design the units to allow oblique fields from head to thigh on patients up to 200 cm in height. Two custom-designed carbon fiber craniospinal tabletop designs now exist: one long and one short. Four are in successful use in our facility. Their weight tolerance is greater than that of our robot table joint (164 kg). The long unit allows for working with taller patients and can be converted into a short unit as needed. An affordable, practical means of doing supine craniospinal therapy with protons or photons can be used in most locations via the use of these devices. This is important because proton therapy provides a much lower integral dose than all other therapy methods for these patients and the supine position is easier for patients to tolerate and for anesthesia delivery. These units have been successfully used for adult and pediatric supine craniospinal therapy, proton therapy using oblique beams to the low pelvis, treatment of various spine tumors, and breast-sparing Hodgkin's therapy.

Modification of male adult simulator posture of ICRP 110 reference; Modificacao da postura do simulador adulto masculino (AM) de referencia da ICRP 110

Energy Technology Data Exchange (ETDEWEB)

Galeano, Diego C.; Souza, Divanizia N.; Santos, Willian S.; Carvalho Junior, Alberico B., E-mail: galeano88@gmail.com [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Dept. de Fisica

2014-07-01

Voxel simulators are usually constructed based on computed tomography and magnetic resonance, so the supine position (lying) is the most used. This may result in a overestimated or underestimated the radiation dose, depending on the exposure scenario adopted. Thus, the objective was to change the attitude of the male adult simulator reference ICRP 110, AM (Adult Male), to a sitting posture. For change of posture were possible, it was necessary increasing the number of slices that comprise AM simulator by reducing the height of the voxel of 8.0 mm to 2.0 mm, thus making each voxel approximately cubic. A subroutine was created in Visual Monte Carlo software (VMC) to rotate the thigh region of the simulator and position it between the region of the leg and trunk. The ScionImage software was used to rebuild and soften the contours of the knee and hip of the simulator in a sitting posture, and 3D visualization of the simulator was used VolView software. The AM simulator in the seated position has the same anatomical features of the simulator in the standing posture. Using the MCNPX code [ref] was carried out the conversion coefficients for calculating the AP irradiation geometry (anteroposterior) comparing the AM simulator standing and sitting in order to evaluate the difference scattering and absorption of radiation by the two simulators. The result shows a difference up to 100% in the fluency conversion coefficients in nearby organs located in the pelvic region and in organs with distribution in the whole body (such as skin, muscle, lymph nodes and skeletal)

Supine Percutaneous Nephrolithotripsy in Double-S Position.

Science.gov (United States)

Giusti, Giuseppe; De Lisa, Antonello

2018-01-01

At present, the percutaneous nephrolithotripsy (PCNL) is performed both in supine and in prone position. The aim of this paper is to describe an innovative position during PCNL. We describe a supine position. The patient's legs are slightly abducted at the hips. The thorax is laterally tilted (inclination 30°-35°) and kept in the right position by one or two gel pads placed between the scapula and the vertebrae. External genitalia can be accessed at any time, so that it is always possible to use flexible instruments in the upper urinary tract. We used this position for a period of 12 months to treat with PCNL 45 patients with renal lithiasis. All the procedures were successfully completed without complications, using the position we are describing. The following are some of its benefits: an easier positioning of the patient; a better exposure of the flank for an easier access to the posterior renal calyces of the kidney; a lower risk of pressure injuries compared to positions foreseeing the use of knee crutches; the possibility of combined procedures (ECIRS) through the use of flexible instruments; and a good fluoroscopic visualization of the kidney not overlapped by the vertebrae. This position is effective, safe, easy, and quick to prepare and allows for combined anterograde/retrograde operations.

Postural variation of pulmonary diffusing capacity as a marker of lung microangiopathy in Indian patients with type 2 diabetes mellitus.

Science.gov (United States)

Kumar, Avinash; Bade, Geetanjali; Trivedi, Anjali; Jyotsna, Viveka P; Talwar, Anjana

2016-01-01

Diabetes mellitus (DM) is characterized by the presence of chronic hyperglycemia and formation of advanced glycation end products (AGEs). Interaction between AGE and its receptor leads to endothelial damage and microangiopathy. This study was undertaken to investigate the possibility of using a postural variation of diffusing capacity as an early marker of lung microangiopathy and its correlation with the level of adhesion molecules, HbA1c, duration of diabetes, and insulin resistance in type 2 DM (T2DM) patients with and without microangiopathy. Forty patients having T2DM without any microangiopathy (n = 20) as well as with microangiopathy (n = 20), and 22 age and sex matched healthy controls were enrolled in this cross-sectional study. Measurement of lung volumes and capacities were done. DLco was measured in sitting and supine position. Levels of vascular cell adhesion molecule-1 (VCAM-1), E-selectin, fasting glucose, and insulin were estimated in plasma of the patients and compared with controls. Restrictive type of ventilatory change was observed in DM patients. Diffusing capacity (% predicted) in the supine position (P capacity in type 2 diabetic patients along with increased VCAM-1 levels could reflect the presence of an early microangiopathy of the small pulmonary vessels.

Effect of Pelvic Tilt and Rotation on Cup Orientation in Both Supine and Standing Positions.

Science.gov (United States)

Yun, Hohyun; Murphy, William S; Ward, Daniel M; Zheng, Guoyan; Hayden, Brett L; Murphy, Stephen B

2018-05-01

The purpose of this study is to analyze the effect of pelvic tilt and rotation on radiographic measurement of cup orientation. A total of 68 patients (79 hips) were included in this study. The patients had a computed tomography study and approximately 3 months of postoperative standing anteroposterior pelvic radiographs in both supine and standing positions. We used 2-dimensional (2D)/3-dimensional (3D) matching to measure pelvic tilt and rotation, and cup orientation. There was a wide range of pelvic tilt between individuals in both supine and standing positions. Supine pelvic tilt was different from standing pelvic tilt (P cup anteversion before and after 2D/3D matching in both supine and standing positions (P cup anteversion before and after 2D/3D matching. When all 79 hips were separated into right and left side, pelvic rotation inversely correlated with the pelvic tilt-adjusted difference in anteversion before and after 2D/3D matching of the right side but directly correlated with that of the left side in both supine and standing positions. This study demonstrated that the measurement of cup anteversion on anteroposterior radiographs is significantly affected by both pelvic tilt and pelvic rotation (depending on the side). Improved understanding of pelvic orientation and improved ability to measure pelvic orientation may eventually allow for desired cup positioning to potentially protect against complications associated with malposition of the cup. Copyright © 2017 Elsevier Inc. All rights reserved.

Influence of posture and positive end-tidal expiratory pressure (PEEP) on clearance of Tc99m-DTPA from the lungs

International Nuclear Information System (INIS)

Mason, G.R.; Maublant, J.; Sietsema, K.; Effros, R.M.; Mena, I.

1984-01-01

The clearance of Tc99m-DTPA aerosols from the lung has been used to detect and quantitate alterations in the permeability of the pulmonary epithelium. Clearance of the radionuclide is accelerated by both chronic and acute injuries to the lung and by smoking. Several laboratories have reported that Tc99m-DTPA clearance from upper lobes exceeded that from lower lobes in upright subjects. To investigate this phenomenon further the authors studied subjects with simultaneous anterior and posterior cameras in upright and supine positions. In the upright position, clearance from both the anterior and posterior upper regions of interest (ROI's) exceeded the lower regions (-1.64 +- .42 S.D. vs. -0.75 +- .41, anterior, p < .05, n=6), -1.04 +- .23 vs. -0.50 +- .36, posterior. All units = %/min. This difference was not observed in the supine subjects. Clearance from the anterior chest exceeded that from the posterior chest in the supine subjects (-1.28 +- .45 vs. -0.05 +- 1.08) and a small increase in radio-activity was observed in at least one ROI of 5 of 6 subjects from the posterior camera. An increase in activity is likely to be secondary to labeling of blood pool, which would have greatest affect where pulmonary blood volume is largest. Computer processing of the entire lung without observer bias in ROI placement showed similar effects of posture over non-peripheral ROI's. Five subjects breathed on PEEP to cause airspace distention, causing clearance to double. Both dependency and airspace distention appear to influence clearance of aerosolized DTPA, the latter may occur by stretching of epithelial pores

Towards incorporating affective computing to virtual rehabilitation; surrogating attributed attention from posture for boosting therapy adaptation

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Rivas, Jesús J.; Heyer, Patrick; Orihuela-Espina, Felipe; Sucar, Luis Enrique

2015-01-01

Virtual rehabilitation (VR) is a novel motor rehabilitation therapy in which the rehabilitation exercises occurs through interaction with bespoken virtual environments. These virtual environments dynamically adapt their activity to match the therapy progress. Adaptation should be guided by the cognitive and emotional state of the patient, none of which are directly observable. Here, we present our first steps towards inferring non-observable attentional state from unobtrusively observable seated posture, so that this knowledge can later be exploited by a VR platform to modulate its behaviour. The space of seated postures was discretized and 648 pictures of acted representations were exposed to crowd-evaluation to determine attributed state of attention. A semi-supervised classifier based on Na¨ıve Bayes with structural improvement was learnt to unfold a predictive relation between posture and attributed attention. Internal validity was established following a 2×5 cross-fold strategy. Following 4959 votes from crowd, classification accuracy reached a promissory 96.29% (µ±σ = 87.59±6.59) and F-measure reached 82.35% (µ ± σ = 69.72 ± 10.50). With the afforded rate of classification, we believe it is safe to claim posture as a reliable proxy for attributed attentional state. It follows that unobtrusively monitoring posture can be exploited for guiding an intelligent adaptation in a virtual rehabilitation platform. This study further helps to identify critical aspects of posture permitting inference of attention.

The retrorenal colon in the supine and prone patient

International Nuclear Information System (INIS)

Hopper, K.D.; Sherman, J.L.; Luethke, J.M.; Ghaed, N.

1986-01-01

Ninety patients underwent CT in both supine and prone positions so that the orientation of the retroperitoneal colon about the kidneys could be determined. Particular attention was given to bowel found posterior to the kidneys, the so-called retrorenal colon. The frequency of retrorenal colon increased from 1.9% on supine studies to 10.7% on prone studies. Since most invasive renal procedures performed with the patient prone would miss retrorenal colon located behind the lateral one third of the kidney, the data were reevaluated, excluding these patients. The resulting frequency of significant retrorenal colon found on prone studies was 4.7%. Significant retrorenal colon was found exclusively at the level of the lower renal poles, and the involved colon in these patients was extensively distended with gas. Particular attention should be given, under fluoroscopic guidance, to detecting this unusual posteriorly positioned, air-filled colon before one undertakes any invasive renal procedure

Postural control and functional balance in individuals with diabetic peripheral neuropathy

Directory of Open Access Journals (Sweden)

Ana Claudia de Souza Fortaleza

2013-03-01

Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2013v15n3p305 Diabetic Peripheral Neuropathy (DPN brings on reduced somatosensation, which can lead to changes in postural control. The objective of this study was to evaluate postural control in a standing position and in different conditions, as well as functional balance in individuals with DPN, make the correlation between the results obtained from the postural control assessment with the values from the functional balance test and compare the results obtained in the neuropathy group with those of the control group, checking for possible differences between the evaluation conditions of both groups. The study included 13 women with DPN (NG and 17 non-diabetic women (CG. Postural control assessment was performed by kinemetry in the following conditions: eyes opened (EO, eyes closed (EC, and semi-tandem (ST. The data was processed in MATLAB and the following variables were generated: mean amplitude of oscillation (MAO in the anterior-posterior (AP and medial-lateral (ML direction; and average speed of oscillation (ASO in AP and ML direction. Functional balance was assessed by the Timed Up and Go Test. There was significant difference between the groups (p≤0.005 in MAO-AP EO and EC, MAO-ML EC and ST, and ASO-ML ST. There were differences between the conditions EO and ST (p≤0.005 and EC and ST (p≤0.005 for the variables MAO-ML and ASO-ML with greater damage to the NG, which also had a lower functional balance (p=0.001. ML instability was positively correlated with functional imbalance. The results show a change in the postural control system in the DPN, which could lead these individuals to a higher risk for falls and functional impairment.

Guide to Good Posture

Science.gov (United States)

... you are moving or still, can prevent pain, injuries, and other health problems. What is posture? Posture is how you hold your body. There are two types: Dynamic posture is how you hold yourself when you are moving, like when you are walking, running, or bending over to pick up something. Static ...

How accurate are measurements of skin-lesion depths on prebiopsy supine chest computed tomography for transthoracic needle biopsies?

International Nuclear Information System (INIS)

Cheung, Joo Yeon; Kim, Yookyung; Shim, Sung Shine; Lee, Jin Hwa; Chang, Jung Hyun; Ryu, Yon Ju; Lee, Rena J.

2012-01-01

Aim: To evaluate the accuracy of depth measurements on supine chest computed tomography (CT) for transthoracic needle biopsy (TNB). Materials and methods: We measured skin-lesion depths from the skin surface to nodules on both prebiopsy supine CT scans and CT scans obtained during cone beam CT-guided TNB in the supine (n = 29) or prone (n = 40) position in 69 patients, and analyzed the differences between the two measurements, based on patient position for the biopsy and lesion location. Results: Skin-lesion depths measured on prebiopsy supine CT scans were significantly larger than those measured on CT scans obtained during TNB in the prone position (p < 0.001; mean difference ± standard deviation (SD), 6.2 ± 5.7 mm; range, 0–18 mm), but the differences showed marginal significance in the supine position (p = 0.051; 3.5 ± 3.9 mm; 0–13 mm). Additionally, the differences were significantly larger for the upper (mean ± SD, 7.8 ± 5.7 mm) and middle (10.1 ± 6.5 mm) lung zones than for the lower lung zones (3.1 ± 3.3 mm) in the prone position (p = 0.011), and were larger for the upper lung zone (4.6 ± 5.0 mm) than for the middle (2.4 ± 2.0 mm) and lower (2.3 ± 2.3 mm) lung zones in the supine position (p = 0.004). Conclusions: Skin-lesion depths measured on prebiopsy supine chest CT scans were inaccurate for TNB in the prone position, particularly for nodules in the upper and middle lung zones.

Somatic features and body posture in children with scoliosis and scoliotic posture

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Jacek Wilczyński

2017-08-01

Full Text Available Abstract The aim of the study was to evaluate the relationship between somatic features and body posture in children with scoliosis and scoliotic posture. The study included 28 girls aged 7-18 with scoliosis and scoliotic posture. The selection of the subjects was deliberate. Height measurements were conducted with an anthropometer and weight measurements were done with an electronic scale. Body posture tests were performed using Exhibeon 3D digital photogrammetry and digital radiographs. The significant Spearman correlations between postural variables for the sagittal plane and the somatic variables regarded: trunk inclination angle and BMI (R= 0,4553, p= p=0,015, Abs of the trunk inclination angle and BMI (R = 0.5522, p = 0.002, length of thoracic kyphosis and BMI (R=0,4147, p=0.028, lumbar lordosis and BMI (R=0,4509, p=0,016. The significant Spearman correlations between scoliotic posture variables and the somatic variables concerned: length of primary lordosis and body height (R =0,4923, p=0.008, the length of the primary lordosis and body mass (R = 0.3932, p = 0.038, the length of the primary lordosis and BMI (R=0,4923, p=0.008. Variation analysis regarding postural (Exhibeon and somatic variables showed significant correlations between the direction of the primary curvature and body mass (p=0,0432, body height and primary angle location (p=0,0290 and between the height of the body and the location of the secondary angle (p = 0,0278.

Difference in human cardiovascular response between upright and supine recovery from upright cycle exercise.

Science.gov (United States)

Takahashi, T; Okada, A; Saitoh, T; Hayano, J; Miyamoto, Y

2000-02-01

Cardiovascular responses were examined in seven healthy male subjects during 10 min of recovery in the upright or supine position following 5 min of upright cycle exercise at 80% peak oxygen uptake. An initial rapid decrease in heart rate (fc) during the early phase of recovery followed by much slower decrease was observed for both the upright and supine positions. The average fc at the 10th min of recovery was significantly lower (P position than in the upright position, while they were both significantly greater than the corresponding pre-exercise levels (each P positions was reduced with a decrease in mean R-R interval, the relationship being expressed by a regression line--mean R-R interval = 0.006 x HF amplitude + 0.570 (r = 0.905, n = 28, P positions is partly attributable to a retardation in the restoration of the activity of the cardiac parasympathetic nervous system. Post-exercise upright stroke volume (SV, by impedance cardiography) decreased gradually to just below the pre-exercise level, whereas post-exercise supine SV increased markedly to a level similar to that at rest before exercise. The resultant cardiac output (Qc) and the total peripheral vascular resistance (TPR) in the upright and supine positions returned gradually to their respective pre-exercise levels in the corresponding positions. At the 10th min of recovery, both average SV and Qc were significantly greater (each P position, while average TPR was significantly lower (P position. In contrast, immediately after exercise, mean blood pressure dropped markedly in both the supine and upright positions, and their levels at the 10th min of recovery were similar. Therefore we concluded that arterial blood pressure is maintained relatively constant through various compensatory mechanisms associated with fc, SV, Qc, and TPR during rest and recovery in different body positions.

Supine Percutaneous Nephrolithotripsy in Double-S Position

Directory of Open Access Journals (Sweden)

Giuseppe Giusti

2018-01-01

Full Text Available Background. At present, the percutaneous nephrolithotripsy (PCNL is performed both in supine and in prone position. The aim of this paper is to describe an innovative position during PCNL. Methods. We describe a supine position. The patient’s legs are slightly abducted at the hips. The thorax is laterally tilted (inclination 30°–35° and kept in the right position by one or two gel pads placed between the scapula and the vertebrae. External genitalia can be accessed at any time, so that it is always possible to use flexible instruments in the upper urinary tract. We used this position for a period of 12 months to treat with PCNL 45 patients with renal lithiasis. Results. All the procedures were successfully completed without complications, using the position we are describing. The following are some of its benefits: an easier positioning of the patient; a better exposure of the flank for an easier access to the posterior renal calyces of the kidney; a lower risk of pressure injuries compared to positions foreseeing the use of knee crutches; the possibility of combined procedures (ECIRS through the use of flexible instruments; and a good fluoroscopic visualization of the kidney not overlapped by the vertebrae. Conclusions. This position is effective, safe, easy, and quick to prepare and allows for combined anterograde/retrograde operations.

The 2-Year Cosmetic Outcome of a Randomized Trial Comparing Prone and Supine Whole-Breast Irradiation in Large-Breasted Women

Energy Technology Data Exchange (ETDEWEB)

Veldeman, Liv, E-mail: liv.veldeman@uzgent.be [Department of Radiation Oncology, University Hospital Ghent, Ghent (Belgium); Department of Radiotherapy and Experimental Cancer Research, Ghent University, Ghent (Belgium); Schiettecatte, Kimberly; De Sutter, Charlotte; Monten, Christel; Greveling, Annick van [Department of Radiation Oncology, University Hospital Ghent, Ghent (Belgium); Berkovic, Patrick [Department of Radiation Oncology, University Hospital Ghent, Ghent (Belgium); Department of Radiation Oncology, Centre Hospitalier Universitaire de Liège, Liège (Belgium); Mulliez, Thomas [Department of Radiation Oncology, University Hospital Ghent, Ghent (Belgium); De Neve, Wilfried [Department of Radiation Oncology, University Hospital Ghent, Ghent (Belgium); Department of Radiotherapy and Experimental Cancer Research, Ghent University, Ghent (Belgium)

2016-07-15

Purpose: To report the 2-year cosmetic outcome of a randomized trial comparing prone and supine whole-breast irradiation in large-breasted patients. Methods and Materials: One hundred patients with a (European) cup size ≥C were included. Before and 2 years after radiation therapy, clinical endpoints were scored and digital photographs were taken with the arms alongside the body and with the arms elevated 180°. Three observers rated the photographs using the 4-point Harvard cosmesis scale. Cosmesis was also evaluated with the commercially available Breast Cancer Conservation Treatment.cosmetic results (BCCT.core) software. Results: Two-year follow-up data and photographs were available for 94 patients (47 supine treated and 47 prone treated). Patient and treatment characteristics were not significantly different between the 2 cohorts. A worsening of color change occurred more frequently in the supine than in the prone cohort (19/46 vs 10/46 patients, respectively, P=.04). Five patients in the prone group (11%) and 12 patients in the supine group (26%) presented with a worse scoring of edema at 2-year follow-up (P=.06). For retraction and fibrosis, no significant differences were found between the 2 cohorts, although scores were generally worse in the supine cohort. The cosmetic scoring by 3 observers did not reveal differences between the prone and supine groups. On the photographs with the hands up, 7 patients in the supine group versus none in the prone group had a worsening of cosmesis of 2 categories using the (BCCT.org) software (P=.02). Conclusion: With a limited follow-up of 2 years, better cosmetic outcome was observed in prone-treated than in supine-treated patients.

Positivity for Convective Semi-discretizations

KAUST Repository

Fekete, Imre

2017-04-19

We propose a technique for investigating stability properties like positivity and forward invariance of an interval for method-of-lines discretizations, and apply the technique to study positivity preservation for a class of TVD semi-discretizations of 1D scalar hyperbolic conservation laws. This technique is a generalization of the approach suggested in Khalsaraei (J Comput Appl Math 235(1): 137–143, 2010). We give more relaxed conditions on the time-step for positivity preservation for slope-limited semi-discretizations integrated in time with explicit Runge–Kutta methods. We show that the step-size restrictions derived are sharp in a certain sense, and that many higher-order explicit Runge–Kutta methods, including the classical 4th-order method and all non-confluent methods with a negative Butcher coefficient, cannot generally maintain positivity for these semi-discretizations under any positive step size. We also apply the proposed technique to centered finite difference discretizations of scalar hyperbolic and parabolic problems.

A Case Report and Review of Postural Orthostatic Tachycardia Syndrome in Pregnancy

Directory of Open Access Journals (Sweden)

Brianna Lide

2015-04-01

Full Text Available Purpose - Postural orthostatic tachycardia syndrome (POTS is a form of orthostatic intolerance characterized by an increased heart rate upon transition from supine to standing, and head-up tilt without orthostatic hypotension. Its etiology is multifactorial, and no clear cause has been identified. Common symptoms include light-headedness, blurred vision, weakness, cognitive difficulties, and fatigue and are often accompanied by palpitations, shortness of breath, syncope, or gastrointestinal symptoms. Management includes volume expansion, physical counter maneuvers, and pharmacological agents such as fludrocortisone, midodrine, propranolol, and pyridostigmine. The course of POTS in pregnancy is variable and POTS has not been directly implicated in any adverse outcomes for the mother or fetus. Methods - Two cases of POTS in pregnancy are presented, along with a review of the literature for reports of POTS in pregnancy. Results - Along with our 2 cases, 10 other case reports were identified and included. Conclusion - The course of POTS in pregnancy is variable, and not directly linked to increase perinatal morbidity or mortality. Women can safely undergo regional anesthesia, and vaginal delivery with close monitoring of hemodynamic changes.

A Case Report and Review of Postural Orthostatic Tachycardia Syndrome in Pregnancy.

Science.gov (United States)

Lide, Brianna; Haeri, Sina

2015-04-01

Purpose Postural orthostatic tachycardia syndrome (POTS) is a form of orthostatic intolerance characterized by an increased heart rate upon transition from supine to standing, and head-up tilt without orthostatic hypotension. Its etiology is multifactorial, and no clear cause has been identified. Common symptoms include light-headedness, blurred vision, weakness, cognitive difficulties, and fatigue and are often accompanied by palpitations, shortness of breath, syncope, or gastrointestinal symptoms. Management includes volume expansion, physical counter maneuvers, and pharmacological agents such as fludrocortisone, midodrine, propranolol, and pyridostigmine. The course of POTS in pregnancy is variable and POTS has not been directly implicated in any adverse outcomes for the mother or fetus. Methods Two cases of POTS in pregnancy are presented, along with a review of the literature for reports of POTS in pregnancy. Results Along with our 2 cases, 10 other case reports were identified and included. Conclusion The course of POTS in pregnancy is variable, and not directly linked to increase perinatal morbidity or mortality. Women can safely undergo regional anesthesia, and vaginal delivery with close monitoring of hemodynamic changes.

SU-E-J-227: Breathing Pattern Consistency and Reproducibility: Comparative Analysis for Supine and Prone Body Positioning

International Nuclear Information System (INIS)

Laugeman, E; Weiss, E; Chen, S; Hugo, G; Rosu, M

2014-01-01

Purpose: Evaluate and compare the cycle-to-cycle consistency of breathing patterns and their reproducibility over the course of treatment, for supine and prone positioning. Methods: Respiratory traces from 25 patients were recorded for sequential supine/prone 4DCT scans acquired prior to treatment, and during the course of the treatment (weekly or bi-weekly). For each breathing cycle, the average(AVE), end-of-exhale(EoE) and end-of-inhale( EoI) locations were identified using in-house developed software. In addition, the mean values and variations for the above quantities were computed for each breathing trace. F-tests were used to compare the cycle-to-cycle consistency of all pairs of sequential supine and prone scans. Analysis of variances was also performed using population means for AVE, EoE and EoI to quantify differences between the reproducibility of prone and supine respiration traces over the treatment course. Results: Consistency: Cycle-to-cycle variations are less in prone than supine in the pre-treatment and during-treatment scans for AVE, EoE and EoI points, for the majority of patients (differences significant at p<0.05). The few cases where the respiratory pattern had more variability in prone appeared to be random events. Reproducibility: The reproducibility of breathing patterns (supine and prone) improved as treatment progressed, perhaps due to patients becoming more comfortable with the procedure. However, variability in supine position continued to remain significantly larger than in prone (p<0.05), as indicated by the variance analysis of population means for the pretreatment and subsequent during-treatment scans. Conclusions: Prone positioning stabilizes breathing patterns in most subjects investigated in this study. Importantly, a parallel analysis of the same group of patients revealed a tendency towards increasing motion amplitude of tumor targets in prone position regardless of their size or location; thus, the choice for body positioning

Lower pole stones: prone PCNL versus supine PCNL in the International Cooperation in Endourology (ICE) group experience.

Science.gov (United States)

Sanguedolce, Francesco; Breda, Alberto; Millan, Felix; Brehmer, Marianne; Knoll, Thomas; Liatsikos, Evangelos; Osther, Palle; Traxer, Olivier; Scoffone, Cesare

2013-12-01

To assess efficacy and safety of prone- and supine percutaneous nephrolithotomy (PCNL) for the treatment of lower pole kidney stones. Data from patients affected by lower pole kidney stones and treated with PCNL between December 2005 and August 2010 were collected retrospectively by seven referral centres. Variables analysed included patient demographics, clinical and surgical characteristics, stone-free rates (SFR) and complications. Statistical analysis was conducted to compare the differences for SFRs and complication rates between prone- and supine PCNL. One hundred seventeen patients underwent PCNL (mean stone size: 19.5 mm) for stones harboured only in the lower renal pole (single stone: 53.6%; multiple stones: 46.4%). A higher proportion of patients with ASA score ≥ 3 and harbouring multiple lower pole stones were treated with supine PCNL (5.8 vs. 23.1%; p = 0.0001, and 25 vs. 81.5%; p = 0.0001, respectively, for prone- and supine PCNL). One-month SFR was 88.9%; an auxiliary procedure was needed in 6 patients; the 3-month SFR was 90.2%. There were 9 post-operative major complications (7.7%). No differences were observed in terms of 1- and 3-month SFRs (90.4 vs. 87.7%; p = 0.64; 92.3 vs. 89.2%; p = 0.4) and complication rates (7.6 vs. 7.7%; p = 0.83) when comparing prone- versus supine PCNL, respectively. The results confirm the high success rate and relatively low morbidity of modern PCNL for lower pole stones, regardless the position used. Supine PCNL was more frequently offered in case of patients at higher ASA score and in case of multiple lower pole stones.

Anesthetic Efficacy of Supine and Upright Positions for the Inferior Alveolar Nerve Block: A Prospective, Randomized Study.

Science.gov (United States)

Crowley, Chase; Drum, Melissa; Reader, Al; Nusstein, John; Fowler, Sara; Beck, Mike

2018-02-01

It has been recommended to place patients in an upright position after administration of an inferior alveolar nerve block (IANB), theoretically allowing the anesthetic to diffuse in an inferior direction and resulting in better pulpal anesthesia. The purpose of this study was to compare an upright versus a supine position on the success of pulpal anesthesia when an IANB was administered in asymptomatic teeth. One hundred ten asymptomatic subjects were randomly given IANBs by using 2% lidocaine with 1:100,000 epinephrine while they were in an upright position and supine position at 2 different appointments spaced at least 2 weeks apart. Pulpal anesthesia was measured in the molars, premolars, and incisors with an electric pulp tester in 4-minute cycles for 60 minutes. Anesthetic success was defined as the subject achieving 2 consecutive 80 readings within 15 minutes of the injection and sustaining the 80 reading for 60 minutes. Success was analyzed by using a mixed model logistic regression. Pulpal anesthesia for the supine position was not statistically more successful than the upright position in the second molars (73% vs 65%), first molars (59% vs 54%), lateral incisors (28% vs 23%), and central incisors (11% vs 8%), respectively. The supine position significantly improved success in the second premolars (63% vs 53%) and first premolars (75% vs 64%). The supine and upright positions were equally successful in the molars and anterior teeth. The supine position was more successful in the premolars. However, clinically, neither position for the IANB administration would provide complete pulpal anesthesia. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Acute Effects of Posture Shirts on Rounded-Shoulder and Forward-Head Posture in College Students.

Science.gov (United States)

Manor, John; Hibberd, Elizabeth; Petschauer, Meredith; Myers, Joseph

2016-12-01

Rounded-shoulder and forward-head posture can be contributing factors to shoulder pain. Corrective techniques such as manual therapy and exercise have been shown to improve these altered postures, but there is little evidence that corrective garments such as posture shirts can alter posture. To determine the acute effects of corrective postureshirt use on rounded-shoulder and forward-head posture in asymptomatic college students. Repeated-measures intervention study with counterbalanced conditions. Research laboratory. 24 members of the general student body of a university, 18-25 y old, with a forward shoulder angle (FSA) >52° and no history of upper-extremity surgery, scoliosis, active shoulder pain, or shoulder pain in the previous 3 mo that restricted participation for 3 consecutive days. Photographic posture assessment under a control condition, under a sham or treatment condition (counterbalanced), under another control condition, and treatment or sham. FSA and forward head angle (FHA) calculated from a lateral photograph. FSA decreased relative to the control condition while participants wore the sham shirt (P = .029) but not the corrective posture shirt (P = 1.00). FHA was unchanged between groups (P = .371). Application of a corrective posture shirt did not acutely alter FSA or FHA, while application of a sham shirt may decrease FSA at rest.

Neck pain and postural balance among workers with high postural demands - a cross-sectional study

DEFF Research Database (Denmark)

Jørgensen, Marie B.; Skotte, Jørgen H.; Holtermann, Andreas

2011-01-01

Neck pain is related to impaired postural balance among patients and is highly prevalent among workers with high postural demands, for example, cleaners. We therefore hypothesised, that cleaners with neck pain suffer from postural dysfunction. This cross-sectional study tested if cleaners with neck...... pain have an impaired postural balance compared with cleaners without neck pain. Postural balance of 194 cleaners with (n = 85) and without (N = 109) neck pain was studied using three different tests. Success or failure to maintain the standing position for 30 s in unilateral stance was recorded...... to cleaners without neck/low back pain (p balance, measured as CEA (p

Neural basis of postural focus effect on concurrent postural and motor tasks: phase-locked electroencephalogram responses.

Science.gov (United States)

Huang, Cheng-Ya; Zhao, Chen-Guang; Hwang, Ing-Shiou

2014-11-01

Dual-task performance is strongly affected by the direction of attentional focus. This study investigated neural control of a postural-suprapostural procedure when postural focus strategy varied. Twelve adults concurrently conducted force-matching and maintained stabilometer stance with visual feedback on ankle movement (visual internal focus, VIF) and on stabilometer movement (visual external focus, VEF). Force-matching error, dynamics of ankle and stabilometer movements, and event-related potentials (ERPs) were registered. Postural control with VEF caused superior force-matching performance, more complex ankle movement, and stronger kinematic coupling between the ankle and stabilometer movements than postural control with VIF. The postural focus strategy also altered ERP temporal-spatial patterns. Postural control with VEF resulted in later N1 with less negativity around the bilateral fronto-central and contralateral sensorimotor areas, earlier P2 deflection with more positivity around the bilateral fronto-central and ipsilateral temporal areas, and late movement-related potential commencing in the left frontal-central area, as compared with postural control with VIF. The time-frequency distribution of the ERP principal component revealed phase-locked neural oscillations in the delta (1-4Hz), theta (4-7Hz), and beta (13-35Hz) rhythms. The delta and theta rhythms were more pronounced prior to the timing of P2 positive deflection, and beta rebound was greater after the completion of force-matching in VEF condition than VIF condition. This study is the first to reveal the neural correlation of postural focusing effect on a postural-suprapostural task. Postural control with VEF takes advantage of efficient task-switching to facilitate autonomous postural response, in agreement with the "constrained-action" hypothesis. Copyright © 2014 Elsevier B.V. All rights reserved.

A randomised trial of Supine versus Prone breast radiotherapy (SuPr study): Comparing set-up errors and respiratory motion

International Nuclear Information System (INIS)

Kirby, Anna M.; Evans, Philip M.; Helyer, Sarah J.; Donovan, Ellen M.; Convery, Helen M.; Yarnold, John R.

2011-01-01

Purpose: To test a prone position against the international-standard supine position in women undergoing whole-breast-radiotherapy (WBRT) after wide-local-excision (WLE) of early breast cancer (BC) in terms of feasibility, set-up errors, and respiratory motion. Methods: Following WLE of BC with insertion of tumour-bed clips, patients underwent 4D-CT for WBRT-planning in supine and prone positions (the latter using an in-house-designed platform). Patients were randomised to undergo WBRT fractions 1-7 in one position, switching to the alternate position for fractions 8-15 (40 Gy/15-fractions total). Cone-beam CT-images (CBCT) were acquired prior to fractions 1, 4, 7, 8, 11 and 14. CBCT data were matched to planning-CT data using (i) chest-wall and (ii) clips. Systematic and random errors were calculated. Maximal displacement of chest-wall and clips with respiration was measured on 4D-CT. Clinical- to planning-target-volume (CTV-PTV) margins were calculated. Patient-comfort-scores and treatment-times were evaluated. Results: Twenty-five patients were randomized. 192/192 (100%) planned supine fractions and 173/192 (90%) prone fractions were completed. 3D population systematic errors were 1.3-1.9 mm (supine) and 3.1-4.3 mm (prone) (p = 0.02) and random errors 2.6-3.2 mm (supine) and 3.8-5.4 mm (prone) (p = 0.02). Prone positioning reduced chest-wall and clip motion (0.5 ± 0.2 mm (prone) versus 2.7 ± 0.5 mm (supine) (p < 0.001)) with respiration. Calculated CTV-PTV margins were greater for prone (12-16 mm) than for supine treatment (10 mm). Patient-comfort-scores and treatment times were comparable (p = 0.06). Conclusions: Set-up errors were greater using our prone technique than for our standard supine technique, resulting in the need for larger CTV-PTV margins in the prone position. Further work is required to optimize the prone treatment-platform and technique before it can become a standard treatment option at our institution.

Comparison of prone versus supine 18F-FDG-PET of locally advanced breast cancer: Phantom and preliminary clinical studies

International Nuclear Information System (INIS)

Williams, Jason M.; Rani, Sudheer D.; Li, Xia; Whisenant, Jennifer G.; Abramson, Richard G.; Arlinghaus, Lori R.; Lee, Tzu-Cheng; MacDonald, Lawrence R.; Partridge, Savannah C.; Kang, Hakmook; Linden, Hannah M.; Kinahan, Paul E.; Yankeelov, Thomas E.

2015-01-01

Purpose: Previous studies have demonstrated how imaging of the breast with patients lying prone using a supportive positioning device markedly facilitates longitudinal and/or multimodal image registration. In this contribution, the authors’ primary objective was to determine if there are differences in the standardized uptake value (SUV) derived from [ 18 F]fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) in breast tumors imaged in the standard supine position and in the prone position using a specialized positioning device. Methods: A custom positioning device was constructed to allow for breast scanning in the prone position. Rigid and nonrigid phantom studies evaluated differences in prone and supine PET. Clinical studies comprised 18F-FDG-PET of 34 patients with locally advanced breast cancer imaged in the prone position (with the custom support) followed by imaging in the supine position (without the support). Mean and maximum values (SUV peak and SUV max , respectively) were obtained from tumor regions-of-interest for both positions. Prone and supine SUV were linearly corrected to account for the differences in 18F-FDG uptake time. Correlation, Bland–Altman, and nonparametric analyses were performed on uptake time-corrected and uncorrected data. Results: SUV from the rigid PET breast phantom imaged in the prone position with the support device was 1.9% lower than without the support device. In the nonrigid PET breast phantom, prone SUV with the support device was 5.0% lower than supine SUV without the support device. In patients, the median (range) difference in uptake time between prone and supine scans was 16.4 min (13.4–30.9 min), which was significantly—but not completely—reduced by the linear correction method. SUV peak and SUV max from prone versus supine scans were highly correlated, with concordance correlation coefficients of 0.91 and 0.90, respectively. Prone SUV peak and SUV max were significantly lower than supine in both

Postural instability in subjects with parkinson’s disease undergoing different sensory pitfalls

Directory of Open Access Journals (Sweden)

Silva Thaís Cardoso Da

2017-12-01

Full Text Available Purpose. Previous research has reported postural instability in subjects with Parkinson’s disease (PD. However, there are still doubts about the effect of sensory stimuli on one’s balance. In this study, we further investigated the stabilometric measures of individuals with PD, analysing the impact of different sensory stimuli on the outcomes. Methods. The total of 26 participants (13 with PD and 13 matched control peers were submitted to 8 sensorimotor dynamics differing in relation to support base (30 cm vs. 10 cm, feet in parallel vs. feet in semi-tandem position, contact surface (foam vs. no foam, and visual conditions (eyes open vs. eyes closed. The measures used to assess one’s balance were body position in space, area of support base, and velocity of postural control. The variables involved the anterior-posterior and the mediolateral axes. Participants with PD were evaluated during the off medication state. Mann-Whitney U test and Friedman’s test were applied to carry out inter- and intra-group comparisons. Significance was set at 5%. Results. Cross-sectional analyses illustrated that tasks with sensory pitfalls impacted postural stability to a larger extent in PD subjects. The differences were found in anterior-posterior body position, area of support base, anterior-posterior velocity, and mediolateral velocity. Complementary analyses confirmed considerable instability on balance when support bases were small and visual information was absent (p < 0.05. Conclusions. The current results confirm worse postural stability response in subjects with PD and highlight that the interference of the sensory pitfalls is notable when individuals are off medication.

[A study on Korean concepts of relaxation].

Science.gov (United States)

Park, J S

1992-01-01

statements, 59 experiences were extracted. And then 9 categories--at rest after physical activities, after problem solving, fancy, bathing in the bed, situation, rest, particular time, others--were organized. 3. The musics of the relaxation; From 229 statements, 108 musics were extracted, and the 9 categories--Western classical music, semi classical music, Korean song, Korean popular classical music, song, western popular song, hymn, characteristics of music, others--were organized. In conclusion, There are some differences between Korean concepts, experiences and musics of relaxation and western concepts, experiences and musics of relaxation.

Supinator Extender (SUE): a pneumatically actuated robot for forearm/wrist rehabilitation after stroke.

Science.gov (United States)

Allington, James; Spencer, Steven J; Klein, Julius; Buell, Meghan; Reinkensmeyer, David J; Bobrow, James

2011-01-01

The robot described in this paper, SUE (Supinator Extender), adds forearm/wrist rehabilitation functionality to the UCI BONES exoskeleton robot and to the ArmeoSpring rehabilitation device. SUE is a 2-DOF serial chain that can measure and assist forearm supination-pronation and wrist flexion-extension. The large power to weight ratio of pneumatic actuators allows SUE to achieve the forces needed for rehabilitation therapy while remaining lightweight enough to be carried by BONES and ArmeoSpring. Each degree of freedom has a range of 90 degrees, and a nominal torque of 2 ft-lbs. The cylinders are mounted away from the patient's body on the lateral aspect of the arm. This is to prevent the danger of a collision and maximize the workspace of the arm robot. The rotation axis used for supination-pronation is a small bearing just below the subject's wrist. The flexion-extension motion is actuated by a cantilevered pneumatic cylinder, which allows the palm of the hand to remain open. Data are presented that demonstrate the ability of SUE to measure and cancel forearm/wrist passive tone, thereby extending the active range of motion for people with stroke.

TU-H-CAMPUS-TeP1-02: Seated Treatment: Setup Uncertainty Comparable to Supine

Energy Technology Data Exchange (ETDEWEB)

McCarroll, R [UT MD Anderson Cancer Center, Houston, TX (United States); UT Health Science Center, Graduate School of Biomedical Sciences, Houston, TX (United States); Beadle, B; Fullen, D; Balter, P; Followill, D; Stingo, F; Yang, J; Court, L [UT MD Anderson Cancer Center, Houston, TX (United States)

2016-06-15

Purpose: For some head and neck patients, positioning in the supine position is not well tolerated. For these patients, treatment in a seated position would be preferred. We have evaluated inter- and intra- fraction uncertainty of patient set-up in a novel treatment chair which is compatible with modern linac designs. Methods: Five head-and-neck cancer patients were positioned in the chair, fitted with immobilization devices, and imaged with orthogonal X-rays. The couch (with chair attached) was rotated to simulate delivery (without actual treatment), another set of images were acquired, providing a measure of intra-fraction displacement. The patient then got off of and back onto the chair and the process was repeated, thus providing a measure of inter-fraction set-up uncertainty. Six sub-regions in the head-and-neck were rigidly registered to evaluate local intra- and interfraction displacement. Image guidance was simulated by first registering one sub-region; the residual displacement of other sub-regions was then measured. Additionally, a patient questionnaire was administered to evaluate tolerance of the seated position. Results: The chair design is such that all advantages of couch motions may be utilized. Average inter- and intrafraction displacements of all sub-regions in the seated position were less than 2 and 3 mm, respectively. When image guidance was simulated, interfraction displacements were reduced by an average of 4 mm, providing comparable setup to the supine position. The enrolled patients, who had no indication for a seated treatment position, reported no preference for the seated or the supine position. Conclusion: The novel chair design provides acceptable inter- and intra-fraction displacement, with reproducibility similar to that observed for patients in the supine position. Such a chair will be utilized for patients who cannot tolerate the supine position and use with CBCT images for planning, in a fixed-beam linac system, and for other

Yoga Training Has Positive Effects on Postural Balance and Its Influence on Activities of Daily Living in People with Multiple Sclerosis: A Pilot Study.

Science.gov (United States)

de Oliveira, Gerson; Tavares, Maria da Consolação Cunha Gomes Fernandes; de Faria Oliveira, Jane Domingues; Rodrigues, Marcos Rojo; Santaella, Danilo Forghieri

2016-01-01

There is a little evidence about the influence of yoga as a complementary therapy for postural balance and its influence on activities of daily living in multiple sclerosis (MS) patients. To evaluate the influence of a six-month yoga program on postural balance and subjective impact of postural balance impairment on activities of daily living in people with MS. Randomized controlled pilot study. Protocol developed at the Adaptive Physical Activity Study Department, College of Physical Education, State University of Campinas, Brazil. A total of 12 (11 women) yoga naive people with MS randomly divided into two groups as follows: Control (C-waiting list, n = 6) and Yoga (Y-Yoga training, n = 6). Yoga group practiced postures, breathing exercises, meditation, and relaxation on weekly 60-min classes for a six-month period. The following evaluations were performed at study entry (baseline), and after six months (six months): Berg Balance Scale (BBS), Expanded Disability Status Scale (EDSS), and self-reported postural balance quality and influence of postural balance on activities of daily living. There was a significant improvement in BBS score from baseline to six months only in the Yoga group, especially in subjects with higher EDSS score, with increased quality of self-reported postural balance, and decreased influence of postural balance impairment on activities of daily living. In conclusion, a six-month yoga training is beneficial for people with MS, since it improves postural balance and decreases the influence of postural balance impairment on activities of daily living. A greater sample size is necessary to increase generalization, but it seems that yoga could be included as a feasible complementary therapy for people with MS. Copyright © 2016 Elsevier Inc. All rights reserved.

The effects of postural changes of baroreflex gain in normal and hypertensive pregnancies.

Science.gov (United States)

Miyake, Yoshiaki; Ohnishi, Miyako; Fujii, T K; Yamamoto, Tatsuo; Yoneda, Chika; Takahashi, Sachie; Ichimaru, Yuhei

2002-01-01

In order to understand the changes of baroreflex gain due to postural changes in normal pregnancies, we measured percentage changes (% changes) in blood pressure (SBP, DBP), heart rate (HR), stroke volume (SV), cardiac output (CO), total peripheral resistance (TPR) as well as cardiac autonomic nervous function (HF as an index of parasympathetic and LF/HF as an index of sympathetic function) and compared these parameters in normal pregnancies with those found in hypertensive pregnancies, such as chronic hypertensive (CHP) and severe preeclamptic pregnancies (PE), in late pregnancy (after 32 wks). When the position was changed from supine to standing in normal and non-pregnant women, the % changes of HR, DBP, TPR and LF/HF were increased and SBP, SV, CO and HF were decreased. The % changes of these parameters, however, were gradually decreased as pregnancy progressed, especially after 20-24 wks of gestation. In hypertensive pregnancies, however, even in late pregnancy, the decreased SBP and increased TPR was still observed and the profound decrease of CO and SV and increase of TPR were characteristic in PE when compared to CHP.

[Surgical treatment of pronation and supination external rotation trimalleolar fractures].

Science.gov (United States)

Xu, Ye-qing; Zhan, Bei-lei; He, Fei-xiong; Wei, Hong-da

2008-04-01

To explore the operative method and its clinical effects of pronation and supination external rotation trimalleolar fractures. From March 2000 to July 2006,42 patients of the pronation and supination external rotation trimalleolar fractures treated with open reduction and internal fixation. Thirty-one were males and 11 were females,with an average age of 40.5 years (from 19 to 76 years). Four cases were open fractures and 38 cases close fractures. The fractures were classified as pronation-external rotation (grade IV) injury in 18 cases and supination-external rotation (grade IV)in 24 cases according to the system of Lauge-Hansen. The time of injury to operation was 2 hours to 27 days. The medial, lateral and posterior malleolus were exposed by standard anteromedial and Gatellier-Chastang approaches. The reduction and internal fixation started with the posterior,then the medial and the lateral malleolus and distal tibiofibular syndesmosis in sequence. The anteroposterior, lateral and mostise X-ray films were taken after operation. All the patients were followed up for an average time of 13.5 months(from 6 to 24 months). The time of union was from 12 to 16 weeks. The results were excellent in 20,good in 16, fair in 4 and poor in 2 cases according to Baird-Jackson ankle scoring system based on pain, stability, walking ability,range of motion and radiological manifestations. The excellent and good rate was 85.7%. There were no infection,malunion and nonunion of the fractures except that the inserted screw to distal tibiofibular syndesmosis was broken in 1 case. The key of operative treatment is to restore the anatomy of ankle and to regain the ankle function maximally.

Comparison of Magnetic Resonance Imaging and Computed Tomography for Breast Target Volume Delineation in Prone and Supine Positions

Energy Technology Data Exchange (ETDEWEB)

Pogson, Elise M. [Centre for Medical Radiation Physics, Faculty of Engineering and Information Sciences, University of Wollongong, Wollongong (Australia); Liverpool and Macarthur Cancer Therapy Centres, Liverpool (Australia); Ingham Institute for Applied Medical Research, Liverpool (Australia); Delaney, Geoff P. [Liverpool and Macarthur Cancer Therapy Centres, Liverpool (Australia); Ingham Institute for Applied Medical Research, Liverpool (Australia); South Western Sydney Clinical School, University of New South Wales, Sydney (Australia); School of Medicine, University of Western Sydney, Sydney (Australia); Ahern, Verity [Crown Princess Mary Cancer Care Centre, Westmead Hospital, Westmead (Australia); Boxer, Miriam M. [Liverpool and Macarthur Cancer Therapy Centres, Liverpool (Australia); South Western Sydney Clinical School, University of New South Wales, Sydney (Australia); Chan, Christine [Department of Radiology, Liverpool Hospital, Liverpool (Australia); David, Steven [Peter MacCallum Cancer Centre, Melbourne (Australia); Dimigen, Marion [Department of Radiology, Liverpool Hospital, Liverpool (Australia); Harvey, Jennifer A. [School of Medicine, University of Queensland, Herston (Australia); Princess Alexandra Hospital, Woolloongabba (Australia); Koh, Eng-Siew [Liverpool and Macarthur Cancer Therapy Centres, Liverpool (Australia); Ingham Institute for Applied Medical Research, Liverpool (Australia); South Western Sydney Clinical School, University of New South Wales, Sydney (Australia); Lim, Karen [Liverpool and Macarthur Cancer Therapy Centres, Liverpool (Australia); South Western Sydney Clinical School, University of New South Wales, Sydney (Australia); Papadatos, George [Liverpool and Macarthur Cancer Therapy Centres, Liverpool (Australia); and others

2016-11-15

Purpose: To determine whether T2-weighted MRI improves seroma cavity (SC) and whole breast (WB) interobserver conformity for radiation therapy purposes, compared with the gold standard of CT, both in the prone and supine positions. Methods and Materials: Eleven observers (2 radiologists and 9 radiation oncologists) delineated SC and WB clinical target volumes (CTVs) on T2-weighted MRI and CT supine and prone scans (4 scans per patient) for 33 patient datasets. Individual observer's volumes were compared using the Dice similarity coefficient, volume overlap index, center of mass shift, and Hausdorff distances. An average cavity visualization score was also determined. Results: Imaging modality did not affect interobserver variation for WB CTVs. Prone WB CTVs were larger in volume and more conformal than supine CTVs (on both MRI and CT). Seroma cavity volumes were larger on CT than on MRI. Seroma cavity volumes proved to be comparable in interobserver conformity in both modalities (volume overlap index of 0.57 (95% Confidence Interval (CI) 0.54-0.60) for CT supine and 0.52 (95% CI 0.48-0.56) for MRI supine, 0.56 (95% CI 0.53-0.59) for CT prone and 0.55 (95% CI 0.51-0.59) for MRI prone); however, after registering modalities together the intermodality variation (Dice similarity coefficient of 0.41 (95% CI 0.36-0.46) for supine and 0.38 (0.34-0.42) for prone) was larger than the interobserver variability for SC, despite the location typically remaining constant. Conclusions: Magnetic resonance imaging interobserver variation was comparable to CT for the WB CTV and SC delineation, in both prone and supine positions. Although the cavity visualization score and interobserver concordance was not significantly higher for MRI than for CT, the SCs were smaller on MRI, potentially owing to clearer SC definition, especially on T2-weighted MR images.

Common postural defects among music students.

Science.gov (United States)

Blanco-Piñeiro, Patricia; Díaz-Pereira, M Pino; Martínez, Aurora

2015-07-01

Postural quality during musical performance affects both musculoskeletal health and the quality of the performance. In this study we examined the posture of 100 students at a Higher Conservatory of Music in Spain. By analysing video tapes and photographs of the students while performing, a panel of experts extracted values of 11 variables reflecting aspects of overall postural quality or the postural quality of various parts of the body. The most common postural defects were identified, together with the situations in which they occur. It is concluded that most students incur in unphysiological postures during performance. It is hoped that use of the results of this study will help correct these errors. Copyright © 2015 Elsevier Ltd. All rights reserved.

Thermoregulatory postures limit antipredator responses in peafowl.

Science.gov (United States)

Yorzinski, Jessica L; Lam, Jennifer; Schultz, Rachel; Davis, Melissa

2018-01-05

Many animals inhabit environments where they experience temperature fluctuations. One way in which animals can adjust to these temperature changes is through behavioral thermoregulation. However, we know little about the thermal benefits of postural changes and the costs they may incur. In this study, we examined the thermoregulatory role of two postures, the head-tuck and leg-tuck posture, in peafowl ( Pavo cristatus ) and evaluated whether the head-tuck posture imposes a predation cost. The heads and legs of peafowl are significantly warmer when the birds exhibit these postures, demonstrating that these postures serve an important thermoregulatory role. In addition, the birds are slower to respond to an approaching threat when they display the head-tuck posture, suggesting that a thermoregulatory posture can limit antipredator behavior. © 2018. Published by The Company of Biologists Ltd.

Thermoregulatory postures limit antipredator responses in peafowl

Directory of Open Access Journals (Sweden)

Jessica L. Yorzinski

2018-01-01

Full Text Available Many animals inhabit environments where they experience temperature fluctuations. One way in which animals can adjust to these temperature changes is through behavioral thermoregulation. However, we know little about the thermal benefits of postural changes and the costs they may incur. In this study, we examined the thermoregulatory role of two postures, the head-tuck and leg-tuck posture, in peafowl (Pavo cristatus and evaluated whether the head-tuck posture imposes a predation cost. The heads and legs of peafowl are significantly warmer when the birds exhibit these postures, demonstrating that these postures serve an important thermoregulatory role. In addition, the birds are slower to respond to an approaching threat when they display the head-tuck posture, suggesting that a thermoregulatory posture can limit antipredator behavior.

[Case of awake intubation in semi-sitting position for a patient with myasthenia gravis combined with cervical disc hernia utilizing Pentax-AWS Airwayscope].

Science.gov (United States)

Komasawa, Nobuyasu; Ueki, Ryusuke; Tomita, Yukihiko; Kaminoh, Yoshiroh; Tashiro, Chikara

2011-01-01

We report a case of awake intubation utilizing Pentax-AWS Airwayscope in semi-sitting position. A 74-year-old man with myasthenia gravis and cervical disc hernia was scheduled for distal gastrectomy under general anesthesia. He could not move his head due to severe cervical disc hernia and also could not sufficiently breathe due to the fatigue of respiratory muscles by myasthenia gravis in supine position. With fentanyl bolus administration and lidocaine spray for laryngotracheal anesthesia, we performed awake intubation in semi-sitting position with AWS from cranial side. The patient did not buck during intubation and no hemodynamic change was observed.

Imaging Posture Veils Neural Signals

Directory of Open Access Journals (Sweden)

Robert T Thibault

2016-10-01

Full Text Available Whereas modern brain imaging often demands holding body positions incongruent with everyday life, posture governs both neural activity and cognitive performance. Humans commonly perform while upright; yet, many neuroimaging methodologies require participants to remain motionless and adhere to non-ecological comportments within a confined space. This inconsistency between ecological postures and imaging constraints undermines the transferability and generalizability of many a neuroimaging assay.Here we highlight the influence of posture on brain function and behavior. Specifically, we challenge the tacit assumption that brain processes and cognitive performance are comparable across a spectrum of positions. We provide an integrative synthesis regarding the increasingly prominent influence of imaging postures on autonomic function, mental capacity, sensory thresholds, and neural activity. Arguing that neuroimagers and cognitive scientists could benefit from considering the influence posture wields on both general functioning and brain activity, we examine existing imaging technologies and the potential of portable and versatile imaging devices (e.g., functional near infrared spectroscopy. Finally, we discuss ways that accounting for posture may help unveil the complex brain processes of everyday cognition.

Unimanual SNARC Effect: Hand Matters

Directory of Open Access Journals (Sweden)

Marianna eRiello

2011-12-01

Full Text Available A structural representation of the hand embedding information about the identity and relative position of fingers is necessary to counting routines. It may also support associations between numbers and allocentric spatial codes that predictably interact with other known numerical spatial representations, such as the mental number line. In this study, 48 Western participants whose typical counting routine proceeded from thumb-to-little on both hands performed magnitude and parity binary judgments. Response keys were pressed either with the right index and middle fingers or with the left index and middle fingers in separate blocks. 24 participants responded with either hands in prone posture (i.e. palm down and 24 participants responded with either hands in supine (i.e. palm up posture. When hands were in prone posture, the counting direction of the left hand conflicted with the direction of the left-right mental number line, whereas the counting direction of the right hand was consistent with it. When hands were in supine posture, the opposite was true. If systematic associations existed between relative number magnitude and an allocentric spatial representation of the finger series within each hand, as predicted on the basis of counting habits, interactions would be expected between hand posture and a unimanual version of the Spatial-Numerical Association of Response Codes (SNARC effect. Data revealed that with hands in prone posture a unimanual SNARC effect was present for the right hand, and with hands in supine posture a unimanual SNARC effect was present for the left hand. We propose that a posture-invariant body structural representation of the finger series provides a relevant frame of reference, a within-hand directional vector, that is associated to simple number processing. Such frame of reference can significantly interact with stimulus-response correspondence effects that have been attributed to the mapping of numbers on a mental

Comparison of prone versus supine 18F-FDG-PET of locally advanced breast cancer: Phantom and preliminary clinical studies

Energy Technology Data Exchange (ETDEWEB)

Williams, Jason M.; Rani, Sudheer D.; Li, Xia; Whisenant, Jennifer G.; Abramson, Richard G. [Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee 37232 and Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee 37232 (United States); Arlinghaus, Lori R. [Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee 37232 (United States); Lee, Tzu-Cheng [Department of Bioengineering, University of Washington, Seattle, Washington 98195 (United States); MacDonald, Lawrence R.; Partridge, Savannah C. [Department of Radiology, University of Washington, Seattle, Washington 98195 (United States); Kang, Hakmook [Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee 37232 and Department of Biostatistics, Vanderbilt University, Nashville, Tennessee 37232 (United States); Linden, Hannah M. [Department of Medical Oncology, University of Washington, Seattle, Washington 98195 (United States); Kinahan, Paul E. [Department of Radiology, University of Washington, Seattle, Washington 98195 (United States); Department of Bioengineering, University of Washington, Seattle, Washington 98195 (United States); Department of Physics, University of Washington, Seattle, Washington 98195 (United States); Department of Electrical Engineering, University of Washington, Seattle, Washington 98195 (United States); Yankeelov, Thomas E., E-mail: thomas.yankeelov@vanderbilt.edu [Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee 37232 (United States); Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee 37232 (United States); Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee 37232 (United States); Department of Physics, Vanderbilt University, Nashville, Tennessee 37232 (United States); Department of Cancer Biology, Vanderbilt University, Nashville, Tennessee 37232 (United States)

2015-07-15

Purpose: Previous studies have demonstrated how imaging of the breast with patients lying prone using a supportive positioning device markedly facilitates longitudinal and/or multimodal image registration. In this contribution, the authors’ primary objective was to determine if there are differences in the standardized uptake value (SUV) derived from [{sup 18}F]fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) in breast tumors imaged in the standard supine position and in the prone position using a specialized positioning device. Methods: A custom positioning device was constructed to allow for breast scanning in the prone position. Rigid and nonrigid phantom studies evaluated differences in prone and supine PET. Clinical studies comprised 18F-FDG-PET of 34 patients with locally advanced breast cancer imaged in the prone position (with the custom support) followed by imaging in the supine position (without the support). Mean and maximum values (SUV{sub peak} and SUV{sub max}, respectively) were obtained from tumor regions-of-interest for both positions. Prone and supine SUV were linearly corrected to account for the differences in 18F-FDG uptake time. Correlation, Bland–Altman, and nonparametric analyses were performed on uptake time-corrected and uncorrected data. Results: SUV from the rigid PET breast phantom imaged in the prone position with the support device was 1.9% lower than without the support device. In the nonrigid PET breast phantom, prone SUV with the support device was 5.0% lower than supine SUV without the support device. In patients, the median (range) difference in uptake time between prone and supine scans was 16.4 min (13.4–30.9 min), which was significantly—but not completely—reduced by the linear correction method. SUV{sub peak} and SUV{sub max} from prone versus supine scans were highly correlated, with concordance correlation coefficients of 0.91 and 0.90, respectively. Prone SUV{sub peak} and SUV{sub max} were

Dorian Supin käis Pärdi asjus Argentinas / T.T.

Index Scriptorium Estoniae

T.T.

2003-01-01

Dokumentaalfilm helilooja Arvo Pärdist "24 prelüüdi ühele fuugale". Filmi stsenarist, režissöör ja operaator Dorian Supin näitas seda suure menuga Buenos Airese San Martini ülikoolis spetsiaalse seminari osavõtjatele

Post-seismic relaxation theory on laterally heterogeneous viscoelastic model

Science.gov (United States)

Pollitz, F.F.

2003-01-01

Investigation was carried out into the problem of relaxation of a laterally heterogeneous viscoelastic Earth following an impulsive moment release event. The formal solution utilizes a semi-analytic solution for post-seismic deformation on a laterally homogeneous Earth constructed from viscoelastic normal modes, followed by application of mode coupling theory to derive the response on the aspherical Earth. The solution is constructed in the Laplace transform domain using the correspondence principle and is valid for any linear constitutive relationship between stress and strain. The specific implementation described in this paper is a semi-analytic discretization method which assumes isotropic elastic structure and a Maxwell constitutive relation. It accounts for viscoelastic-gravitational coupling under lateral variations in elastic parameters and viscosity. For a given viscoelastic structure and minimum wavelength scale, the computational effort involved with the numerical algorithm is proportional to the volume of the laterally heterogeneous region. Examples are presented of the calculation of post-seismic relaxation with a shallow, laterally heterogeneous volume following synthetic impulsive seismic events, and they illustrate the potentially large effect of regional 3-D heterogeneities on regional deformation patterns.

Postural Coordination during Socio-motor Improvisation.

Science.gov (United States)

Gueugnon, Mathieu; Salesse, Robin N; Coste, Alexandre; Zhao, Zhong; Bardy, Benoît G; Marin, Ludovic

2016-01-01

Human interaction often relies on socio-motor improvisation. Creating unprepared movements during social interaction is not a random process but relies on rules of synchronization. These situations do not only involve people to be coordinated, but also require the adjustment of their posture in order to maintain balance and support movements. The present study investigated posture in such a context. More precisely, we first evaluated the impact of amplitude and complexity of arm movements on posture in solo situation. Then, we assessed the impact of interpersonal coordination on posture using the mirror game in which dyads performed improvised and synchronized movements (i.e., duo situation). Posture was measured through ankle-hip coordination in medio-lateral and antero-posterior directions (ML and AP respectively). Our results revealed the spontaneous emergence of in-phase pattern in ML direction and antiphase pattern in AP direction for solo and duo situations. These two patterns respectively refer to the simultaneous flexion/extension of the ankles and the hips in the same or opposite direction. It suggests different functional roles of postural coordination patterns in each direction, with in-phase supporting task performance in ML (dynamical stability) and antiphase supporting postural control in AP (mechanical stability). Although amplitude of movement did not influence posture, movement complexity disturbed postural stability in both directions. Conversely, interpersonal coordination promoted postural stability in ML but not in AP direction. These results are discussed in terms of the difference in coupling strength between ankle-hip coordination and interpersonal coordination.

Postural coordination during socio-motor improvisation

Directory of Open Access Journals (Sweden)

Mathieu Gueugnon

2016-08-01

Full Text Available Human interaction often relies on socio-motor improvisation. Creating unprepared movements during social interaction is not a random process but relies on rules of synchronization. These situations do not only involve people to be coordinated, but also require the adjustment of their posture in order to maintain balance and support movements. The present study investigated posture in such a context. More precisely, we first evaluated the impact of amplitude and complexity of arm movements on posture in solo situation. Then, we assessed the impact of interpersonal coordination on posture using the mirror game in which dyads performed improvised and synchronized movements (i.e., duo situation. Posture was measured through ankle-hip coordination in medio-lateral and antero-posterior directions (ML and AP respectively. Our results revealed the spontaneous emergence of in-phase pattern in ML direction and anti-phase pattern in AP direction for solo and duo situations. These two patterns respectively refer to the simultaneous flexion/extension of the ankles and the hips in the same or opposite direction. It suggests different functional roles of postural coordination patterns in each direction, with in-phase supporting task performance in ML (dynamical stability and antiphase supporting postural control in AP (mechanical stability. Although amplitude of movement did not influence posture, movement complexity disturbed postural stability in both directions. Conversely, interpersonal coordination promoted postural stability in ML but not in AP direction. These results are discussed in terms of the difference in coupling strength between ankle-hip coordination and interpersonal coordination.

Detecting altered postural control after cerebral concussion in athletes with normal postural stability

OpenAIRE

Cavanaugh, J; Guskiewicz, K; Giuliani, C; Marshall, S; Mercer, V; Stergiou, N

2005-01-01

Objective: To determine if approximate entropy (ApEn), a regularity statistic from non-linear dynamics, could detect changes in postural control during quiet standing in athletes with normal postural stability after cerebral concussion.

Prone versus supine thallium myocardial SPECT: A method to decrease artifactual inferior wall defects

International Nuclear Information System (INIS)

Segall, G.M.; Davis, M.J.

1989-01-01

Artifactual inferior wall defects as a result of diaphragmatic attenuation of activity are a frequent source of error in thallium myocardial single photon emission computed tomography (SPECT) studies. Thirty-four patients and 11 clinically normal volunteers were studied prospectively to see if specificity of inferior wall defects for right coronary artery disease could be improved by scanning patients prone versus supine. All individuals were scanned both prone and supine, in random order, following symptom limited treadmill exercise. Images were acquired at 3 degrees steps, 25 sec per frame, in a 180 degrees elliptical orbit always beginning in the 45 degrees right anterior oblique position relative to the patient. Polar maps generated from the short axis slices were used to calculate the average regional activity. The prone studies showed consistently higher inferior wall activity compared to the supine studies on both the exercise (182 +/- 22 vs. 160 +/- 23, p less than or equal to 0.001) and 4-hr delay studies (183 +/- 20 vs. 175 +/- 21, p less than or equal to 0.001). Prone imaging resulted in a significantly higher specificity for RCA disease compared to supine imaging (90% vs. 66%, p less than 0.05) with an improvement in accuracy from 71% to 82%. Sensitivity, specificity, and accuracy for left anterior descending and left circumflex artery disease were not significantly affected by patient position during imaging. All patients having SPECT thallium myocardial perfusion studies should be imaged prone to minimize artifactual inferior wall defects and improve accuracy

Pronation-Supination Motion Is Altered in a Rat Model of Post-Traumatic Elbow Contracture.

Science.gov (United States)

Dunham, Chelsey L; Castile, Ryan M; Chamberlain, Aaron M; Galatz, Leesa M; Lake, Spencer P

2017-07-01

The elbow joint is highly susceptible to joint contracture, and treating elbow contracture is a challenging clinical problem. Previously, we established an animal model to study elbow contracture that exhibited features similar to the human condition including persistent decreased range of motion (ROM) in flexion-extension and increased capsule thickness/adhesions. The objective of this study was to mechanically quantify pronation-supination in different injury models to determine if significant differences compared to control or contralateral persist long-term in our animal elbow contracture model. After surgically inducing soft tissue damage in the elbow, Injury I (anterior capsulotomy) and Injury II (anterior capsulotomy with lateral collateral ligament transection), limbs were immobilized for 6 weeks (immobilization (IM)). Animals were evaluated after the IM period or following an additional 6 weeks of free mobilization (FM). Total ROM for pronation-supination was significantly decreased compared to the uninjured contralateral limb for both IM and FM, although not different from control limbs. Specifically, for both IM and FM, total ROM for Injury I and Injury II was significantly decreased by ∼20% compared to contralateral. Correlations of measurements from flexion-extension and pronation-supination divulged that FM did not affect these motions in the same way, demonstrating that joint motions need to be studied/treated separately. Overall, injured limbs exhibited persistent motion loss in pronation-supination when comparing side-to-side differences, similar to human post-traumatic joint contracture. Future work will use this animal model to study how elbow periarticular soft tissues contribute to contracture.

[Outcome of operative treatment for supination-external rotation Lauge-Hansen stage IV ankle fractures].

Science.gov (United States)

Kołodziej, Łukasz; Boczar, Tomasz; Bohatyrewicz, Andrzej; Zietek, Paweł

2010-01-01

Ankle fractures are among the most common musculoskeletal injures. These fractures occur with an overall age- and sex-adjusted incidence rate around 180 per 100 000 person-years. The most frequent mechanism is considered to be supination-external rotation (60 to 80% of all ankle fractures) consisting of pathologic external rotation of the foot initially placed in some degree of supination. According to Lauge-Hansen classification, ankle joint structures are damaged in a sequence where the final, stage IV injuries, represents transverse fracture of the medial malleolus or its equivalent-rupture of the deltoid ligament. The aim of this study is to compare the results of two subtypes of supination-external rotation stage IV fractures. 43 patients treated surgically in 2006 to 2007 at Authors institution because of stage IV supination-external rotation ankle fracture were submitted to retrospective analysis. There were 25 patients with bimalleolar fracture (type 1) and in 18 patients with lateral malleolar fracture with accompanying rupture of the deltoid ligament (type 2). The mean age was 46 years (from 20 to 82 years). Average follow up period was 37 months (from 24 to 46 months). For the evaluation of treatment AOFAS hind-foot score (American Orthopedic Foot and Ankle Society) was used. The mean AOFAS score scale for Type 1 fractures was 85 points and for type 2 was significantly higher and amounted to 91 points (p ankle fractures with medial malleolar fracture, requires the implementation of additional diagnostic and therapeutic strategies and procedures in order to improve the outcome of results.

Comparison of CT myelography performed in the prone and supine positions in the detection of cervical spinal stenosis

International Nuclear Information System (INIS)

Blease Graham, Cole III; Wippold, Franz J. II; Bae, Kyongtae T.; Pilgram, Thomas K.; Shaibani, Ali; Kido, Daniel K.

2001-01-01

AIM: To quantify the change in the cross-sectional area of the cervical spinal cord and subarachnoid space (SAS) in the supine neutral vs prone extension positions in patients with myelopathy undergoing cervical CT myelography. MATERIAL AND METHODS: Axial CT myelgrams of 21 myelopathic patients were performed in both the supine neutral and prone extension positions. The SAS and cord cross-sectional areas were then measured at the disk spaces and mid-pedicle levels from C2 to T1 in both the supine and prone positions using a public domain NIH Image program, version 156b18. Mean area measurements in both positions were then compared for each level examined. RESULTS: Mean SAS cross-sectional area in the prone position was notably reduced compared with the supine position at C4-C5 [128.8 mm 2 vs 168.1 mm 2 (P 2 vs 143.2 mm 2 (P< .05)] disk levels. The mean cord cross-sectional area failed to change signficantly with positioning. CONCLUSIONS: Prone myelography may demonstrate a greater degree of cervical spine stenosis compared with CT myelography performed in the supine position in myelopathic patients. Imaging with the patient prone with neck extended in both myelography and CTM may improve precision in the results of measurements of the stenotic spinal canal when comparing these two methods. Blease Graham III, C. (2001)

Anatomy and histochemistry of hindlimb flight posture in birds. I. The extended hindlimb posture of shorebirds.

Science.gov (United States)

McFarland, Joshua C; Meyers, Ron A

2008-08-01

Birds utilize one of two hindlimb postures during flight: an extended posture (with the hip and knee joints flexed, while the ankle joint is extended caudally) or a flexed posture (with the hip, knee, and ankle joints flexed beneath the body). American Avocets (Recurvirostra americana) and Black-necked Stilts (Himantopus mexicanus) extend their legs caudally during flight and support them for extended periods. Slow tonic and slow twitch muscle fibers are typically found in muscles functioning in postural support due to the fatigue resistance of these fibers. We hypothesized that a set of small muscles composed of high percentages of slow fibers and thus dedicated to postural support would function in securing the legs in the extended posture during flight. This study examined the anatomy and histochemical profile of eleven hindlimb muscles to gain insight into their functional roles during flight. Contrary to our hypothesis, all muscles possessed both fast twitch and slow twitch or slow tonic fibers. We believe this finding is due to the versatility of dynamic and postural functions the leg muscles must facilitate, including standing, walking, running, swimming, and hindlimb support during flight. Whether birds use an extended or flexed hindlimb flight posture may be related to the aerodynamic effect of leg position or may reflect evolutionary history. (c) 2008 Wiley-Liss, Inc.

Physiological Response to Static Muscle Contractions in Standing and Supine Positions

DEFF Research Database (Denmark)

Pedersen, Jens Meldgaard; Andersen, T. Bull

2013-01-01

The purpose of this study was to investigate the physiological responses to static muscle contractions in the standing position and the supine position. Eight subjects performed static contractions of the ankle extensors in both positions. Blood pressure (SBP and DBP), heart rate (HR...

SU-F-T-536: Contra-Lateral Breast Study for Prone Versus Supine Patients

Energy Technology Data Exchange (ETDEWEB)

Marrero, M; Joseph, K; Klein, E [Northwell Health, Lake Success, NY (United States)

2016-06-15

Purpose: There are several advantages to utilizing the prone technique for intact breast cancer patients. However, as the topography changes, accompanied by the influence of a supporting breast board and patient treatment couch, the question that arises is to whether there is a concern for contralateral breast dose for intact breast cancer patients being treated with this technique. Methods: An anthropomorphic phantom with breast mounds to duplicate intact breast cancer treatment was planned in prone and supine position. Two tangential beams were executed in the similar manner for as the radiotherapy planning system. For the prone setup, a breast dense foam board was used to support the phantom. A grid of 24 OSL nanodots was placed at 6cm, 4cm, and 2cm apart from the medial border for both prone and supine setups. The phantom was set up using megavoltage imaging and treated as per plan. Additional, a similar study was performed on a patient treated in prone position. Results: Overall, the contralateral breast dose was generally higher for prone setups at all locations especially when close to the medial border. The average mean dose was found to be 1.8%, 2.5% of the prescribed dose for supine respectively prone position. The average of the standard deviation is 1.04%, 1.38% for supine respectively prone position. As for patient treated in prone position average mean dose was found to be 1.165% of the prescribed dose and average of the standard deviation is 9.456%. Conclusion: There is minimal influence of scatter from the breast board. It appears that the volatility of the setup could lead to higher doses than expected from the planning system to the contralateral breast when the patient is in the prone position.

The dentist's operating posture - ergonomic aspects.

Science.gov (United States)

Pîrvu, C; Pătraşcu, I; Pîrvu, D; Ionescu, C

2014-06-15

The practice of dentistry involves laborious high finesse dental preparations, precision and control in executions that require a particular attention, concentration and patience of the dentist and finally the dentist's physical and mental resistance. The optimal therapeutic approach and the success of practice involve special working conditions for the dentist and his team in an ergonomic environment. The meaning of the posture in ergonomics is the manner in which different parts of the body are located and thus the reports are established between them in order to allow a special task execution. This article discusses the posture adopted by dentists when they work, beginning with the balanced posture and going to different variants of posture. The ideal posture of a dentist gives him, on the one hand the optimal working conditions (access, visibility and control in the mouth) and on the other hand, physical and psychological comfort throughout the execution of the clinical acts. Although the theme of dentist posture is treated with great care and often presented in the undergraduate courses and the continuing education courses on ergonomics in dentistry, many dentists do not know the subject well enough nor the theoretical issues and therefore nor the practical applicability. The risk and perspective of the musculoskeletal disorders related to unbalanced postures should determine the dentists take postural corrective actions and compensation measures in order to limit the negative effects of working in a bad posture.

Relationship between Muscle Function, Muscle Typology and Postural Performance According to Different Postural Conditions in Young and Older Adults.

Science.gov (United States)

Paillard, Thierry

2017-01-01

Although motor output of the postural function clearly influences postural performance in young and older subjects, no relationship has been formally established between them. However, the relationship between lower-extremity muscle strength/power and postural performance is often pointed out, especially in older subjects. In fact, the influence of motor output may vary according to the postural condition considered (e.g., static, dynamic, challenging, disturbing). In static postural condition, there may be a relationship between lower-extremity muscle strength and postural performance when the value of muscle strength is below a certain threshold in older subjects. Above this threshold of muscle strength, this relationship may disappear. In dynamic postural condition, lower-extremity muscle power could facilitate compensatory postural actions, limiting induced body imbalance likely to generate falls in older subjects. In young subjects, there could be a relationship between very early rapid torque of the leg extensor muscles and postural performance. In the case of postural reaction to (external) perturbations, a high percentage of type II muscle fibers could be associated with the ability to react quickly to postural perturbations in young subjects, while it may enable a reduction in the risk of falls in older subjects. In practice, in older subjects, muscle strength and/or power training contributes to reducing the risk of falls, as well as slowing down the involution of muscle typology regarding type II muscle fibers.

Modelflow Estimates of Stroke Volume Do Not Correlate With Doppler Ultrasound Estimates During Upright Posture

Science.gov (United States)

Ferguson, Connor R.; Lee, Stuart M. C.; Stenger, Michael B.; Platts, Steven H.; Laurie, Steven S.

2014-01-01

Orthostatic intolerance affects 60-80% of astronauts returning from long-duration missions, representing a significant risk to completing mission-critical tasks. While likely multifactorial, a reduction in stroke volume (SV) represents one factor contributing to orthostatic intolerance during stand and head up tilt (HUT) tests. Current measures of SV during stand or HUT tests use Doppler ultrasound and require a trained operator and specialized equipment, restricting its use in the field. BeatScope (Finapres Medical Systems BV, The Netherlands) uses a modelflow algorithm to estimate SV from continuous blood pressure waveforms in supine subjects; however, evidence supporting the use of Modelflow to estimate SV in subjects completing stand or HUT tests remain scarce. Furthermore, because the blood pressure device is held extended at heart level during HUT tests, but allowed to rest at the side during stand tests, changes in the finger arterial pressure waveform resulting from arm positioning could alter modelflow estimated SV. The purpose of this project was to compare Doppler ultrasound and BeatScope estimations of SV to determine if BeatScope can be used during stand or HUT tests. Finger photoplethysmography was used to acquire arterial pressure waveforms corrected for hydrostatic finger-to-heart height using the Finometer (FM) and Portapres (PP) arterial pressure devices in 10 subjects (5 men and 5 women) during a stand test while simultaneous estimates of SV were collected using Doppler ultrasound. Measures were made after 5 minutes of supine rest and while subjects stood for 5 minutes. Next, SV estimates were reacquired while each arm was independently raised to heart level, a position similar to tilt testing. Supine SV estimates were not significantly different between all three devices (FM: 68+/-20, PP: 71+/-21, US: 73+/-21 ml/beat). Upon standing, the change in SV estimated by FM (-18+/-8 ml) was not different from PP (-21+/-12), but both were significantly

Fifteen Minutes of Chair-Based Yoga Postures or Guided Meditation Performed in the Office Can Elicit a Relaxation Response

Directory of Open Access Journals (Sweden)

Geoffrey W. Melville

2012-01-01

Full Text Available This study compared acute (15 min yoga posture and guided meditation practice, performed seated in a typical office workspace, on physiological and psychological markers of stress. Twenty participants (39.6±9.5 yr completed three conditions: yoga, meditation, and control (i.e., usual work separated by ≥24 hrs. Yoga and meditation significantly reduced perceived stress versus control, and this effect was maintained postintervention. Yoga increased heart rate while meditation reduced heart rate versus control (<0.05. Respiration rate was reduced during yoga and meditation versus control (<0.05. Domains of heart rate variability (e.g., SDNN and Total Power were significantly reduced during control versus yoga and meditation. Systolic and diastolic blood pressure were reduced secondary to meditation versus control only (<0.05. Physiological adaptations generally regressed toward baseline postintervention. In conclusion, yoga postures or meditation performed in the office can acutely improve several physiological and psychological markers of stress. These effects may be at least partially mediated by reduced respiration rate.

Validity and Reliability of Gait and Postural Control Analysis Using the Tri-axial Accelerometer of the iPod Touch.

Science.gov (United States)

Kosse, Nienke M; Caljouw, Simone; Vervoort, Danique; Vuillerme, Nicolas; Lamoth, Claudine J C

2015-08-01

Accelerometer-based assessments can identify elderly with an increased fall risk and monitor interventions. Smart devices, like the iPod Touch, with built-in accelerometers are promising for clinical gait and posture assessments due to easy use and cost-effectiveness. The aim of the present study was to establish the validity and reliability of the iPod Touch for gait and posture assessment. Sixty healthy participants (aged 18-75 years) were measured with an iPod Touch and stand-alone accelerometer while they walked under single- and dual-task conditions, and while standing in parallel and semi-tandem stance with eyes open, eyes closed and when performing a dual task. Cross-correlation values (CCV) showed high correspondence of anterior-posterior and medio-lateral signal patterns (CCV's ≥ 0.88). Validity of gait parameters (foot contacts, index of harmonicity, and amplitude variability) and standing posture parameters [root mean square of accelerations, median power frequency (MPF) and sway area] as indicated by intra-class correlation (ICC) was high (ICC = 0.85-0.99) and test-retest reliability was good (ICC = 0.81-0.97), except for MPF (ICC = 0.59-0.87). Overall, the iPod Touch obtained valid and reliable measures of gait and postural control in healthy adults of all ages under different conditions. Additionally, smart devices have the potential to be used for clinical gait and posture assessments.

Relationship between postural alignment in sitting by photogrammetry and seated postural control in post-stroke subjects.

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Iyengar, Y R; Vijayakumar, K; Abraham, J M; Misri, Z K; Suresh, B V; Unnikrishnan, B

2014-01-01

This study was executed to find out correlation between postural alignment in sitting measured through photogrammetry and postural control in sitting following stroke. A cross-sectional study with convenient sampling consisting of 45 subjects with acute and sub-acute stroke. Postural alignment in sitting was measured through photogrammetry and relevant angles were obtained through software MB Ruler (version 5.0). Seated postural control was measured through Function in Sitting Test (FIST). Correlation was obtained using Spearman's Rank Correlation co-efficient in SPSS software (version 17.0). Moderate positive correlation (r = 0.385; p < 0.01) was found between angle of lordosis and angle between acromion, lateral epicondyle and point between radius and ulna. Strong negative correlation (r = -0.435; p < 0.01) was found between cranio-vertebral angle and kyphosis. FIST showed moderate positive correlation (r = 0.3446; p < 0.05) with cranio-vertebral angle and strong positive correlation (r = 0.4336; p < 0.01) with Brunnstrom's stage of recovery in upper extremity. Degree of forward head posture in sitting correlates directly with seated postural control and inversely with degree of kyphosis in sitting post-stroke. Postural control in sitting post-stroke is directly related with Brunnstrom's stage of recovery in affected upper extremity in sitting.

On the functional integration between postural and supra-postural tasks on the basis of contextual cues and task constraint.

Science.gov (United States)

de Lima, Andrea Cristina; de Azevedo Neto, Raymundo Machado; Teixeira, Luis Augusto

2010-10-01

In order to evaluate the effects of uncertainty about direction of mechanical perturbation and supra-postural task constraint on postural control, young adults had their upright stance perturbed while holding a tray in a horizontal position. Stance was perturbed by moving forward or backward a supporting platform, contrasting situations of certainty versus uncertainty of direction of displacement. Increased constraint on postural stability was imposed by a supra-postural task of equilibrating a cylinder on the tray. Performance was assessed through EMG of anterior leg muscles, angular displacement of the main joints involved in the postural reactions and displacement of the tray. Results showed that both certainty on the direction of perturbation and increased supra-postural task constraint led to decreased angular displacement of the knee and the hip. Furthermore, combination of certainty and high supra-postural task constraint produced shorter latency of muscular activation. Such postural responses were paralleled by decreased displacement of the tray. These results suggest a functional integration between the tasks, with central set priming reactive postural responses from contextual cues and increased stability demand. Copyright © 2010 Elsevier B.V. All rights reserved.

Neck pain and postural balance among workers with high postural demands - a cross-sectional study

Science.gov (United States)

2011-01-01

Background Neck pain is related to impaired postural balance among patients and is highly prevalent among workers with high postural demands, for example, cleaners. We therefore hypothesised, that cleaners with neck pain suffer from postural dysfunction. This cross-sectional study tested if cleaners with neck pain have an impaired postural balance compared with cleaners without neck pain. Methods Postural balance of 194 cleaners with (n = 85) and without (N = 109) neck pain was studied using three different tests. Success or failure to maintain the standing position for 30 s in unilateral stance was recorded. Participants were asked to stand on a force platform for 30 s in the Romberg position with eyes open and closed. The centre of pressure of the sway was calculated, and separated into a slow (rambling) and fast (trembling) component. Subsequently, the 95% confidence ellipse area (CEA) was calculated. Furthermore a perturbation test was performed. Results More cleaners with neck pain (81%) failed the unilateral stance compared with cleaners without neck pain (61%) (p neck pain in comparison with cleaners without neck pain in the Romberg position with eyes closed, but not with eyes open. Conclusions Postural balance is impaired among cleaners with neck pain and the current study suggests a particular role of the slow component of postural sway. Furthermore, the unilateral stance test is a simple test to illustrate functional impairment among cleaners with concurrent neck and low back pain. Trial registration ISRCTN96241850 PMID:21806796

Alternated Prone and Supine Whole-Breast Irradiation Using IMRT: Setup Precision, Respiratory Movement and Treatment Time

International Nuclear Information System (INIS)

Veldeman, Liv; De Gersem, Werner; Speleers, Bruno; Truyens, Bart; Van Greveling, Annick; Van den Broecke, Rudy; De Neve, Wilfried

2012-01-01

Purpose: The objective of this study was to compare setup precision, respiration-related breast movement and treatment time between prone and supine positions for whole-breast irradiation. Methods and Materials: Ten patients with early-stage breast carcinoma after breast-conserving surgery were treated with prone and supine whole breast-irradiation in a daily alternating schedule. Setup precision was monitored using cone-beam computed tomography (CBCT) imaging. Respiration-related breast movement in the vertical direction was assessed by magnetic sensors. The time needed for patient setup and for the CBCT procedure, the beam time, and the length of the whole treatment slot were also recorded. Results: Random and systematic errors were not significantly different between positions in individual patients for each of the three axes (left-right, longitudinal, and vertical). Respiration-related movement was smaller in prone position, but about 80% of observations showed amplitudes <1 mm in both positions. Treatment slots were longer in prone position (21.2 ± 2.5 min) than in supine position (19.4 ± 0.8 min; p = 0.044). Conclusion: Comparison of setup precision between prone and supine position in the same patient showed no significant differences in random and systematic errors. Respiratory movement was smaller in prone position. The longer treatment slots in prone position can probably be attributed to the higher repositioning need.

Automated Assessment of Postural Stability (AAPS)

Science.gov (United States)

2016-10-01

performed a battery of standard clinical tests of dynamic posture, whereas the fourth subject performed the stereotyped postures (e.g. movements restricted...Processing & Control [2] Napoli A, Ward C, Glass S, Tucker C, Obeid I (2016) “Automated Assessment of Postural Stability System,” IEEE Engineering in

Postural hemodynamic changes after turning to prone position

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Микола Віталійович Лизогуб

2015-03-01

Full Text Available Background of study. Prone position is one of the most complex positions for anesthesiologist as it is accompanied by several physiological changes that can lead to specific complications. Hemodynamic changes are most controversial.Aim of study was to establish hemodynamic changes in non-anaesthetized patients in prone position depending on body mass index.Material and methods. We examined central hemodynamics in 40 patients the day before surgery using thoracic rheography in supine position, in prone position 5 min after turning and in prone position 20 min after turning. Patients were divided into 2 groups according to body mass index (18-25 and 26-35.Results. Patients with normal body weight did not have any hemodynamic changes after turning to prone position. Patients with increased body weight had higher cardiac index. After turning to prone position obese patients’ cardiac output and cardiac index reduced 22% comparing with supine position. After 20 min in prone position these hemodynamic parameters were found to be reduced to the same level.Conclusion. Significant hemodynamic changes after turning from supine to prone position were revealed only in patients with increased body mass index. In these patients cardiac index in prone position was reduced by 22% comparing to supine position

Gait, posture and cognition in Parkinson's disease

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Alessandra Ferreira Barbosa

Full Text Available ABSTRACT Gait disorders and postural instability are the leading causes of falls and disability in Parkinson's disease (PD. Cognition plays an important role in postural control and may interfere with gait and posture assessment and treatment. It is important to recognize gait, posture and balance dysfunctions by choosing proper assessment tools for PD. Patients at higher risk of falling must be referred for rehabilitation as early as possible, because antiparkinsonian drugs and surgery do not improve gait and posture in PD.

Examining the stability of dual-task posture and reaction time measures in older adults over five sessions: a pilot study.

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Jehu, Deborah A; Paquet, Nicole; Lajoie, Yves

2016-12-01

Improved performance may be inherent due to repeated exposure to a testing protocol. However, limited research has examined this phenomenon in postural control. The aim was to determine the influence of repeated administration of a dual-task testing protocol once per week for 5 weeks on postural sway and reaction time. Ten healthy older adults (67.0 ± 6.9 years) stood on a force plate for 30 s in feet apart and semi-tandem positions while completing simple reaction time (SRT) and choice reaction time (CRT) tasks. They were instructed to stand as still as possible while verbally responding as fast as possible to the stimuli. No significant differences in postural sway were shown over time (p > 0.05). A plateau in average CRT emerged as the time effect revealed longer CRT during session 1 compared to sessions 3-5 (p task context. Postural sway and SRT were stable over the 5 testing sessions, but variability of CRT continued to improve over time. These findings form a basis for future studies to examine performance-related improvements due to repeated exposure to a testing protocol in a dual-task setting.

Postural Control in Children with Autism.

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Kohen-Raz, Reuven; And Others

1992-01-01

Postural control was evaluated in 91 autistic, 166 normal, and 18 mentally retarded children using a computerized posturographic procedure. In comparison to normal children, the autistic subjects were less likely to exhibit age-related changes in postural performance, and postures were more variable and less stable. (Author/JDD)

Normovolemia defined according to cardiac stroke volume in healthy supine humans

DEFF Research Database (Denmark)

Bundgaard-Nielsen, Morten; Jørgensen, Christoffer C; Kehlet, Henrik

2010-01-01

, mean +/- SD), SV was measured by esophageal Doppler before and after fluid administration to evaluate whether SV increases in healthy, non-fasting, supine subjects. Two hundred millilitres of a synthetic colloid (hydroxyethyl starch, HES 130/0.4) was provided and repeated if a >or=10% increment in SV...

Relaxation and kinetics in scalar field theories

International Nuclear Information System (INIS)

Boyanovsky, D.; Lawrie, I.D.; Lee, D.

1996-01-01

A new approach to the dynamics of relaxation and kinetics of thermalization in a scalar field theory is presented that incorporates the relevant time scales through the resummation of hard thermal loops. An alternative derivation of the kinetic equations for the open-quote open-quote quasiparticle close-quote close-quote distribution functions is obtained that allows a clear understanding of the different open-quote open-quote coarse-graining close-quote close-quote approximations usually involved in a kinetic description. This method leads to a systematic perturbative expansion to obtain the kinetic equations including hard thermal loop resummation and to an improvement including renormalization, off-shell effects, and contributions that change chemical equilibrium on short time scales. As a by-product of these methods we establish the equivalence between the relaxation time scale in the linearized equation of motion of the quasiparticles and the thermalization time scale of the quasiparticle distribution function in the open-quote open-quote relaxation time approximation close-quote close-quote including hard thermal loop effects. Hard thermal loop resummation dramatically modifies the scattering rate for long wavelength modes as compared to the usual (semi)classical estimate. Relaxation and kinetics are studied both in the unbroken and broken symmetry phases of the theory. The broken symmetry phase also provides the setting to obtain the contribution to the kinetic equations from processes that involve decay of a heavy scalar into light scalar particles in the medium. copyright 1996 The American Physical Society

Kinematics of the human mandible for different head postures.

Science.gov (United States)

Visscher, C M; Huddleston Slater, J J; Lobbezoo, F; Naeije, M

2000-04-01

The influence of head posture on movement paths of the incisal point (IP) and of the mandibular condyles during free open-close movements was studied. Ten persons, without craniomandibular or cervical spine disorders, participated in the study. Open close mandibular movements were recorded with the head in five postures, viz., natural head posture, forward head posture, military posture, and lateroflexion to the right and to the left side, using the Oral Kinesiologic Analysis System (OKAS-3D). This study showed that in a military head posture, the opening movement path of the incisal point is shifted anteriorly relative to the path in a natural head posture. In a forward head posture, the movement path is shifted posteriorly whereas during lateroflexion, it deviates to the side the head has moved to. Moreover, the intra-articular distance in the temporomandibular joint during closing is smaller with the head in military posture and greater in forward head posture, as compared to the natural head posture. During lateroflexion, the intra-articular distance on the ipsilateral side is smaller. The influence of head posture upon the kinematics of the mandible is probably a manifestation of differences in mandibular loading in the different head postures.

The Relationship Between Postural and Movement Stability.

Science.gov (United States)

Feldman, Anatol G

2016-01-01

Postural stabilization is provided by stretch reflexes, intermuscular reflexes, and intrinsic muscle properties. Taken together, these posture-stabilizing mechanisms resist deflections from the posture at which balance of muscle and external forces is maintained. Empirical findings suggest that for each muscle, these mechanisms become functional at a specific, spatial threshold-the muscle length or respective joint angle at which motor units begin to be recruited. Empirical data suggest that spinal and supraspinal centers can shift the spatial thresholds for a group of muscles that stabilized the initial posture. As a consequence, the same stabilizing mechanisms, instead of resisting motion from the initial posture, drive the body to another stable posture. In other words by shifting spatial thresholds, the nervous system converts movement resisting to movement-producing mechanisms. It is illustrated that, contrary to conventional view, this control strategy allows the system to transfer body balance to produce locomotion and other actions without loosing stability at any point of them. It also helps orient posture and movement with the direction of gravity. It is concluded that postural and movement stability is provided by a common mechanism.

Semi-parametric estimation for ARCH models

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Raed Alzghool

2018-03-01

Full Text Available In this paper, we conduct semi-parametric estimation for autoregressive conditional heteroscedasticity (ARCH model with Quasi likelihood (QL and Asymptotic Quasi-likelihood (AQL estimation methods. The QL approach relaxes the distributional assumptions of ARCH processes. The AQL technique is obtained from the QL method when the process conditional variance is unknown. We present an application of the methods to a daily exchange rate series. Keywords: ARCH model, Quasi likelihood (QL, Asymptotic Quasi-likelihood (AQL, Martingale difference, Kernel estimator

Visual Vection does not Perturb Squatting Posture

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Dietrich Gilles

2011-12-01

Full Text Available Vision contributes fundamentally to the control of the standing posture. The illusion of self motion falsely perceived (vection increases postural sway while standing. In this paper we examine the effect of vection on both standing and deep squatting with the hypothesis that the squatting posture should not be disturbed by the conflict of sensory information due to vection. The results show that standing posture only was affected by the visual stimuli. The widespread use of squatting for work as well as rest could be due in part to this lack of effect of sensory perturbation on postural stability.

Sensitivity of bedside ultrasound and supine anteroposterior chest radiographs for the identification of pneumothorax after blunt trauma.

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Wilkerson, R Gentry; Stone, Michael B

2010-01-01

Supine anteroposterior (AP) chest radiographs in patients with blunt trauma have poor sensitivity for the identification of pneumothorax. Ultrasound (US) has been proposed as an alternative screening test for pneumothorax in this population. The authors conducted an evidence-based review of the medical literature to compare sensitivity of bedside US and AP chest radiographs in identifying pneumothorax after blunt trauma. MEDLINE and EMBASE databases were searched for trials from 1965 through June 2009 using a search strategy derived from the following PICO formulation of our clinical question: patients included adult (18 + years) emergency department (ED) patients in whom pneumothorax was suspected after blunt trauma. The intervention was thoracic ultrasonography for the detection of pneumothorax. The comparator was the supine AP chest radiograph during the initial evaluation of the patient. The outcome was the diagnostic performance of US in identifying the presence of pneumothorax in the study population. The criterion standard for the presence or absence of pneumothorax was computed tomography (CT) of the chest or a rush of air during thoracostomy tube placement (in unstable patients). Prospective, observational trials of emergency physician (EP)-performed thoracic US were included. Trials in which the exams were performed by radiologists or surgeons, or trials that investigated patients suffering penetrating trauma or with spontaneous or iatrogenic pneumothoraces, were excluded. The methodologic quality of the studies was assessed. Qualitative methods were used to summarize the study results. Data analysis consisted of test performance (sensitivity and specificity, with 95% confidence intervals [CIs]) of thoracic US and supine AP chest radiography. Four prospective observational studies were identified, with a total of 606 subjects who met the inclusion and exclusion criteria. The sensitivity and specificity of US for the detection of pneumothorax ranged from

Peridural anesthesia and the distribution of blood in supine humans

International Nuclear Information System (INIS)

Arndt, J.O.; Hoeck, A.S.; Stanton-Hicks, M.; Stuehmeier, K.D.

1985-01-01

To determine the effects of vasomotor tone on intrathoracic and splanchnic blood volume, the distribution of radioactively (/sup 99m/Tc) labeled erythrocytes was recorded by whole body scintigraphy before and during peridural anesthesia (PDA) in eight supine men. The radioactivity was recorded with a gamma camera and its distribution determined in the thorax, abdomen, and limbs. Arterial and central venous pressure, heart rate, and calf volume and flow also were measured. During PDA with a sensory block up to T4/5, radioactivity increased only in the denervated legs, whereas it decreased in all other regions, i.e., in the thorax, the innervated upper limbs, and in the splanchnic vasculature. However, in two of the subjects, after an initial decrease, splanchnic blood content increased while intrathoracic blood volume decreased further. The effects of PDA on thoracic and splanchnic filling could be duplicated by the sequestration of about 500-600 ml of blood in both legs. In supine humans high peridural anesthesia evokes the same decrease in intrathoracic blood volume as orthostasis. Potential circulatory collapse may ensue when the vasoconstrictor response fails in the splanchnic circulation

Differences in abdominal organ movement between supine and prone positions measured using four-dimensional computed tomography

International Nuclear Information System (INIS)

Kim, Young Seok; Park, Sung Ho; Ahn, Seung Do; Lee, Jeong Eun; Choi, Eun Kyung; Lee, Sang-wook; Shin, Seong Soo; Yoon, Sang Min; Kim, Jong Hoon

2007-01-01

Background and purpose: To analyze the differences in intrafractional organ movement throughout the breathing cycles between the supine and prone positions using four-dimensional computed tomography (4D CT). Materials and methods: We performed 4D CT on nine volunteers in the supine and prone positions, with each examinee asked to breathe normally during scanning. The movement of abdominal organs in the cranio-caudal (CC), anterior-posterior (AP) and right-left (RL) directions was quantified by contouring on each phase between inspiration and expiration. Results: The mean intrafractional motions of the hepatic dome, lower tip, pancreatic head and tail, both kidneys, spleen, and celiac axis in the supine/prone position were 17.3/13.0, 14.4/11.0, 12.8/8.9, 13.0/10.0, 14.3/12.1, 12.3/12.6, 11.7/12.6 and 2.2/1.8 mm, respectively. Intrafractional movements of the liver dome and pancreatic head were reduced significantly in the prone position. The CC directional excursions were major determinants of the 3D displacements of the abdominal organs. Alteration from the supine to the prone position did not change the amount of intrafractional movements of kidneys, spleen, and celiac axis. Conclusion: There was a significant reduction in the movements of the liver and pancreas during the prone position, especially in the CC direction, suggesting possible advantage of radiotherapy to these organs in this position

Goal-directed fluid therapy: stroke volume optimisation and cardiac dimensions in supine healthy humans

DEFF Research Database (Denmark)

Jans, O.; Tollund, C.; Bundgaard-Nielsen, M.

2008-01-01

BACKGROUND: Based on maximisation of cardiac stroke volume (SV), peri-operative individualised goal-directed fluid therapy improves patient outcome. It remains, however, unknown how fluid therapy by this strategy relates to filling of the heart during supine rest as reference for the anaesthetised...... by thoracic electrical admittance, central venous oxygenation and pressure, and arterial plasma atrial natriuretic peptide. Also, muscle and brain oxygenation were assessed by near infrared spectroscopy (n=7). RESULTS: The HUT reduced the mentioned indices of CBV, the end-diastolic dimensions of the heart...... therapy is that when a maximal SV is established for patients, cardiac pre-load is comparable to that of supine healthy subjects Udgivelsesdato: 2008/4...

Postural Stability of Patients with Schizophrenia during Challenging Sensory Conditions: Implication of Sensory Integration for Postural Control.

Science.gov (United States)

Teng, Ya-Ling; Chen, Chiung-Ling; Lou, Shu-Zon; Wang, Wei-Tsan; Wu, Jui-Yen; Ma, Hui-Ing; Chen, Vincent Chin-Hung

2016-01-01

Postural dysfunctions are prevalent in patients with schizophrenia and affect their daily life and ability to work. In addition, sensory functions and sensory integration that are crucial for postural control are also compromised. This study intended to examine how patients with schizophrenia coordinate multiple sensory systems to maintain postural stability in dynamic sensory conditions. Twenty-nine patients with schizophrenia and 32 control subjects were recruited. Postural stability of the participants was examined in six sensory conditions of different level of congruency of multiple sensory information, which was based on combinations of correct, removed, or conflicting sensory inputs from visual, somatosensory, and vestibular systems. The excursion of the center of pressure was measured by posturography. Equilibrium scores were derived to indicate the range of anterior-posterior (AP) postural sway, and sensory ratios were calculated to explore ability to use sensory information to maintain balance. The overall AP postural sway was significantly larger for patients with schizophrenia compared to the controls [patients (69.62±8.99); controls (76.53±7.47); t1,59 = -3.28, pmaintain balance compared to the controls.

An evaluation of intrafraction motion of the prostate in the prone and supine positions using electromagnetic tracking

International Nuclear Information System (INIS)

Shah, Amish P.; Kupelian, Patrick A.; Willoughby, Twyla R.; Langen, Katja M.; Meeks, Sanford L.

2011-01-01

Purpose: To evaluate differences in target motion during prostate irradiation in the prone versus supine position using electromagnetic tracking to measure prostate mobility. Materials/methods: Twenty patients received prostate radiotherapy in the supine position utilizing the Calypso Localization System (registered) for prostate positioning and monitoring. For each patient, 10 treatment fractions were followed by a session in which the patient was repositioned prone, and prostate mobility was tracked. The fraction of time that the prostate was displaced by >3, 5, 7, and 10 mm was calculated for each patient, for both positions (400 tracking sessions). Results: Clear patterns of respiratory motion were seen in the prone tracks due to the influence of increased abdominal motion. Averaged over all patients, the prostate was displaced >3 and 5 mm for 37.8% and 10.1% of the total tracking time in the prone position, respectively. In the supine position, the prostate was displaced >3 and 5 mm for 12.6% and 2.9%, respectively. With both patient setups, inferior and posterior drifts of the prostate position were observed. Averaged over all prone tracking sessions, the prostate was displaced >3 mm in the posterior and inferior directions for 11.7% and 9.5% of the total time, respectively. Conclusions: With real-time tracking of the prostate, it is possible to study the effects of different setup positions on the prostate mobility. The percentage of time the prostate moved >3 and 5 mm was increased by a factor of three in the prone versus supine position. For larger displacements (>7 mm) no difference in prostate mobility was observed between prone and supine positions. To reduce rectal toxicity, radiotherapy in the prone position may be a suitable alternative provided respiratory motion is accounted for during treatment. Acute and late toxicity results remain to be evaluated for both patient positions.

Syndesmotic fixation in supination-external rotation ankle fractures: a prospective randomized study.

Science.gov (United States)

Pakarinen, Harri J; Flinkkilä, Tapio E; Ohtonen, Pasi P; Hyvönen, Pekka H; Lakovaara, Martti T; Leppilahti, Juhana I; Ristiniemi, Jukka Y

2011-12-01

This study was designed to assess whether transfixion of an unstable syndesmosis is necessary in supination-external rotation (Lauge-Hansen SE/Weber B)-type ankle fractures. A prospective study of 140 patients with unilateral Lauge-Hansen supination-external rotation type 4 ankle fractures was done. After bony fixation, the 7.5-Nm standardized external rotation (ER) stress test for both ankles was performed under fluoroscopy. A positive stress examination was defined as a difference of more than 2 mm side-to-side in the tibiotalar or tibiofibular clear spaces on mortise radiographs. If the stress test was positive, the patient was randomized to either syndesmotic transfixion with 3.5-mm tricortical screws or no syndesmotic fixation. Clinical outcome was assessed using the Olerud-Molander scoring system, RAND 36-Item Health Survey, and Visual Analogue Scale (VAS) to measure pain and function after a minimum 1-year of followup. Twenty four (17%) of 140 patients had positive standardized 7.5-Nm ER stress tests after malleolar fixation. The stress view was positive three times on tibiotalar clear space, seven on tibiofibular clear space, and 14 times on both tibiotalar and tibiofibular clear spaces. There was no significant difference between the two randomization groups with regards to Olerud-Molander functional score, VAS scale measuring pain and function, or RAND 36-Item Health Survey pain or physical function at 1 year. Relevant syndesmotic injuries are rare in supination-external rotation ankle fractures, and syndesmotic transfixion with a screw did not influence the functional outcome or pain after the 1-year followup compared with no fixation.

Exercise and relaxation intervention for patients with advanced lung cancer

DEFF Research Database (Denmark)

Adamsen, Lis; Stage, M; Laursen, J

2012-01-01

Lung cancer patients experience loss of physical capacity, dyspnea, pain, reduced energy and psychological distress. The aim of this study was to explore feasibility, health benefits and barriers of exercise in former sedentary patients with advanced stage lung cancer, non-small cell lung cancer...... (NSCLC) (III-IV) and small cell lung cancer (SCLC) (ED), undergoing chemotherapy. The intervention consisted of a hospital-based, supervised, group exercise and relaxation program comprising resistance-, cardiovascular- and relaxation training 4 h weekly, 6 weeks, and a concurrent unsupervised home......-based exercise program. An explorative study using individual semi-structured interviews (n=15) and one focus group interview (n=8) was conducted among the participants. Throughout the intervention the patients experienced increased muscle strength, improvement in wellbeing, breathlessness and energy. The group...

Substantial effect of acute hydration on blood pressure in patients with autonomic failure

DEFF Research Database (Denmark)

Mehlsen, J; Boesen, F

1987-01-01

fraction were measured in the supine position. Measurements were repeated after rapid infusion of 11 of isotonic saline. Acute hydration resulted in increased supine mean blood pressure levels (P less than 0.01) despite normal plasma volumes in all patients. The postural reductions in mean blood pressure......The effect of acute hydration on arterial blood pressure levels was investigated in ten patients with severe postural hypotension due to autonomic failure. Blood pressure and heart rate were determined in the supine and 60-degree head-up tilted position. Plasma volume and left ventricular ejection...... were reduced from 40 mmHg before to 20 mmHg after saline (median values, P less than 0.01). The results indicate that normal plasma volumes do not ensure optimal circulatory status in patients with autonomic failure. Acute hydration with isotonic saline may be used for immediate corrections of blood...

An improved Lagrangian relaxation and dual ascent approach to facility location problems

DEFF Research Database (Denmark)

Jörnsten, Kurt; Klose, Andreas

2016-01-01

not be reduced to the same extent as in the case of ordinary semi-Lagrangian relaxation. Hence, an effective method for optimizing the Lagrangian dual function is of utmost importance for obtaining a computational advantage from the simplified Lagrangian dual function. In this paper, we suggest a new dual ascent...... method for optimizing both the semi-Lagrangian dual function as well as its simplified form for the case of a generic discrete facility location problem and apply the method to the uncapacitated facility location problem. Our computational results show that the method generally only requires a very few...

Education and the Prevention of Postural Defects

Directory of Open Access Journals (Sweden)

Olchowska-Kotala Agnieszka

2014-12-01

Full Text Available Purpose. The aim of this study was to determine: whether and at what stage of education is proper body posture learned, the intention of young adults to participate in activities teaching proper posture, and the effects of factors related with the said intention. Methods. The study involved 430 university students aged 18-24 years. Anthropometric data was collected. Participants completed questionnaires assessing physical activity level (IPAQ and their intention to participate in extracurricular activities teaching proper posture while sitting or walking, proper running technique, corrective gymnastics, or weight loss exercises. A self-assessment of posture, physical fitness, attractiveness, and body satisfaction was also completed. Results. Lower back pain was experienced by 41% of the respondents. Most were taught proper posture-related habits in primary school, followed by secondary school, and then at university. Many students expressed their intention to participate in the extracurricular activities. None of the questionnaire variables were associated with the intention to learn proper walking posture or proper running technique. The intention to participate in classes teaching proper sitting posture was associated with lower back pain in women and low physical activity level in men. In women, a relationship was found between the intention to participate in weight loss exercises and body dissatisfaction, high BMI, and poor self-evaluations of posture and attractiveness. In men, this activity was associated with body dissatisfaction. Conclusions. There is a need for further education on the development of proper postural habits at the university level.

Stress growth and relaxation of dendritically branched macromolecules in shear and uniaxial extension

DEFF Research Database (Denmark)

Huang, Qian; Costanzo, S.; Das, C.

2017-01-01

stress relaxation, suggesting a strong ‘elastic memory’ of the material. These results are 2 described by BoB semi-quantitatively, both in linear and nonlinear shear and extensional regimes. Given the fact that the segments between branch points are less than 3 entanglements long, this is a very...... of stretches of different parts of the polymer appears to be the origin of the slower subsequent relaxation of extensional stress. Concerning the latter effect, for which predictions are not available, it is hoped that the present experimental findings and proposed framework of analysis will motivate further...

Gait, posture and cognition in Parkinson's disease

OpenAIRE

Barbosa, Alessandra Ferreira; Chen, Janini; Freitag, Fernanda; Valente, Debora; Souza, Carolina de Oliveira; Voos, Mariana Callil; Chien, Hsin Fen

2016-01-01

ABSTRACT Gait disorders and postural instability are the leading causes of falls and disability in Parkinson's disease (PD). Cognition plays an important role in postural control and may interfere with gait and posture assessment and treatment. It is important to recognize gait, posture and balance dysfunctions by choosing proper assessment tools for PD. Patients at higher risk of falling must be referred for rehabilitation as early as possible, because antiparkinsonian drugs and surgery do n...

Postural ortostatisk takykardisyndrom

DEFF Research Database (Denmark)

Brinth, Louise; Pors, Kirsten; Mehlsen, Jesper

2014-01-01

Postural orthostatic tachycardia syndrome (POTS) is a heterogeneous condition of dysautonomia and suspected autoimmunity characterized by abnormal increments in heart rate upon assumption of the upright posture accompanied by symptoms of cerebral hypoperfusion and sympathoexcitation. An increase...... in heart rate equal to or greater than 30 bpm or to levels higher than 120 bpm during a head-up tilt test is the main diagnostic criterion. Management includes both non-pharmacological and pharmacological treatment focusing on stress management, volume expansion and heart rate control....

The relaxational behaviour of poly-(vinylidene fluoride) before and after gamma-irradiation

International Nuclear Information System (INIS)

Callens, A.

The main purpose of this work was to investigate how molecular chain reorganization may affect the physical property of polymers. This may be done by the analysis of the as received and post-irradiation relaxation spectra of the semi-crystalline linear chain polymer polyvinylidene fluoride (PVDF), which has been gamma-irradiated up to doses of 1 grad. The effects of the irradiation on the material are primarly main chain cross-linking production of unsaturated bonds and crystallite degradation. To reach a complete interpretation of the relaxation spectra, it is necessary to incorporate a third phase into the analysis besides the amorphous viscoelastic region (AVR) and the crystalline viscoelastic region (CVR), the intermediate phase. The amorphous phase (AVR) is at the origin of the relaxation effects occurring in the temperature region below room temperature. The saturation like behaviour of the cross-linking in the amorphous phase is at the origin of the intensity decrease, temperature shift and peak broadening of the beta relaxation. There is a large amount of evidence that in the neighbourhood of the beta relaxation, relaxation effects are created through irradiation, as mainly revealed by TSD-spectra (thermalloy stimulated depolarisation). The intensity of the gamma relaxation, gradually increases with dose, which has been attributed to the production of disordered chain from the debris of radiation enhanced crystallite destruction. The relaxation effect, occuring at the temperatures between AVR and CVR, is assigned to the long amorphous chain segments attached partly to the crystallites, mainly from the consideration of the similarity of the dose enhanced decrease in intensity of both beta and βsub(μ)-effects. The increase with dose of the intensity of the α1 relaxation, which has been classified within CVR, confirms the grainboundary hypothesis. The second component of CVR (α2 relaxation) is due to relaxation effects of molecular chains belonging to the

Relationships among head posture, pain intensity, disability and deep cervical flexor muscle performance in subjects with postural neck pain

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Arun V. Subbarayalu, PhD

2017-12-01

Full Text Available Objectives: Information Technology (IT professionals working with computers gradually develop forward head posture and, as a result, these professionals are susceptible to several neck disorders. This study intended to reveal the relationships between pain intensity, disability, head posture and deep cervical flexor (DCF muscle performance in patients with postural neck pain. Methods: A cross-sectional study was conducted on 84 IT professionals who were diagnosed with postural neck pain. The participants were recruited with a random sampling approach. A Visual Analogue Scale (VAS, the Northwick Park Neck Pain Questionnaire (NPQ, the Modified Head Posture Spinal Curvature Instrument (MHPSCI, and the Stabilizer Pressure Biofeedback Unit were used to measure neck pain intensity, neck disability, head posture, and DCF muscle performance, respectively. Results: The Pearson correlation coefficient revealed a significantly strong positive relationship between the VAS and the NPQ (r = 0.734. The cranio-vertebral (CV angle was found to have a significantly negative correlation with the VAS (r = −0.536 and a weak negative correlation with the NPQ (r = −0.389. Conclusion: This study concluded that a smaller CV angle corresponded to greater neck pain intensity and disability. Furthermore, there is no significant relationship between CV angle and DCF muscle performance, indicating that head posture re-education through postural correction exercises would not completely correct the motor control deficits in DCF muscles. In addition, a suitable exercise regimen that exclusively targets the deep cervical flexor muscle to improve its endurance is warranted. Keywords: Craniovertebral angle, Disability deep cervical flexors muscle performance, Head posture, Postural neck pain

Unimanual SNARC Effect: Hand Matters.

Science.gov (United States)

Riello, Marianna; Rusconi, Elena

2011-01-01

A structural representation of the hand embedding information about the identity and relative position of fingers is necessary to counting routines. It may also support associations between numbers and allocentric spatial codes that predictably interact with other known numerical spatial representations, such as the mental number line (MNL). In this study, 48 Western participants whose typical counting routine proceeded from thumb-to-little on both hands performed magnitude and parity binary judgments. Response keys were pressed either with the right index and middle fingers or with the left index and middle fingers in separate blocks. 24 participants responded with either hands in prone posture (i.e., palm down) and 24 participants responded with either hands in supine (i.e., palm up) posture. When hands were in prone posture, the counting direction of the left hand conflicted with the direction of the left-right MNL, whereas the counting direction of the right hand was consistent with it. When hands were in supine posture, the opposite was true. If systematic associations existed between relative number magnitude and an allocentric spatial representation of the finger series within each hand, as predicted on the basis of counting habits, interactions would be expected between hand posture and a unimanual version of the spatial-numerical association of response codes (SNARC) effect. Data revealed that with hands in prone posture a unimanual SNARC effect was present for the right hand, and with hands in supine posture a unimanual SNARC effect was present for the left hand. We propose that a posture-invariant body structural representation of the finger series provides a relevant frame of reference, a within-hand directional vector, that is associated to simple number processing. Such frame of reference can significantly interact with stimulus-response correspondence effects, like the SNARC, that have been typically attributed to the mapping of numbers on a left

Thermoregulatory postures limit antipredator responses in peafowl

OpenAIRE

Jessica L. Yorzinski; Jennifer Lam; Rachel Schultz; Melissa Davis

2018-01-01

Many animals inhabit environments where they experience temperature fluctuations. One way in which animals can adjust to these temperature changes is through behavioral thermoregulation. However, we know little about the thermal benefits of postural changes and the costs they may incur. In this study, we examined the thermoregulatory role of two postures, the head-tuck and leg-tuck posture, in peafowl (Pavo cristatus) and evaluated whether the head-tuck posture imposes a predation cost. The h...

A Stabilized Incompressible SPH Method by Relaxing the Density Invariance Condition

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Mitsuteru Asai

2012-01-01

Full Text Available A stabilized Incompressible Smoothed Particle Hydrodynamics (ISPH is proposed to simulate free surface flow problems. In the ISPH, pressure is evaluated by solving pressure Poisson equation using a semi-implicit algorithm based on the projection method. Even if the pressure is evaluated implicitly, the unrealistic pressure fluctuations cannot be eliminated. In order to overcome this problem, there are several improvements. One is small compressibility approach, and the other is introduction of two kinds of pressure Poisson equation related to velocity divergence-free and density invariance conditions, respectively. In this paper, a stabilized formulation, which was originally proposed in the framework of Moving Particle Semi-implicit (MPS method, is applied to ISPH in order to relax the density invariance condition. This formulation leads to a new pressure Poisson equation with a relaxation coefficient, which can be estimated by a preanalysis calculation. The efficiency of the proposed formulation is tested by a couple of numerical examples of dam-breaking problem, and its effects are discussed by using several resolution models with different particle initial distances. Also, the effect of eddy viscosity is briefly discussed in this paper.

Optical coherence tomography evaluation of patients with macula-off retinal detachment after different postoperative posturing: a randomized pilot study.

Science.gov (United States)

Peiretti, Enrico; Nasini, Francesco; Buschini, Elisa; Caminiti, Giulia; Lesnik Oberstein, Sarit Y; Willig, Alissa; Bijl, Heico M; Mura, Marco

2017-08-01

To assess the presence of outer and inner retinal folds (RFs) and drop-out of the ellipsoid zone (EZ) occurring after surgical repair of macula-off rhegmatogenous retinal detachment (RRD) with different postoperative posture and preoperative use of adjuvant perfluorocarbon liquid (PFCO). In this prospective study, 56 eyes of 56 consecutive patients affected by RRD were subjected to 23- or 25-gauge pars plana vitrectomy (PPV). The patients were randomized in four groups (14 prone 5 hr without PFCO, 14 supine 5 hr without PFCO, 14 prone 5 hr with PFCO and 14 supine 5 hr with PFCO) and followed up with spectral domain optical coherence tomography (SD-OCT). Spectral domain optical coherence tomography (SD-OCT) was recorded before surgery, at days 30 and 90 to detect the presence of outer RFs, inner RFs and drop-out of EZ and to follow their variation over time. No statistical significance was found in our groups for outer RFs, inner RFs, drop-out of EZ formation and evolution. The postoperative best-corrected visual acuity (BCVA) improved in all groups (mean preoperative BCVA 1.47 logMar ± 0.19, mean postoperative BCVA 0.27 logMar ± 0.11, p < 0.01), without statistical variations between the four groups in BCVA after surgery. The use of adjuvant and variation in postoperative position did not change the risk of presenting outer RFs, inner RFs and drop-out of EZ after RRD. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Effects of neurofeedback training on the brain wave of adults with forward head posture

Science.gov (United States)

Oh, Hyun-Ju; Song, Gui-Bin

2016-01-01

[Purpose] The purpose of the present study was to examine the effects of neurofeedback training on electroencephalogram changes in the cervical spine in adults with forward head posture through x-ray. [Subjects and Methods] The subjects of the study were 40 college students with forward head posture, randomly divided into a neurofeedback training group (NFTG, n=20) and a control group (CG, n=20). The neurofeedback training group performed six sessions of pottery and archery games, each for two minutes, three times per week for four weeks, while using the neurofeedback system. [Results] There were significant effects within and between groups in terms of the Delta wave, the Theta wave, the Alpha wave, the Beta wave, or the sensory motor rhythm. Especially, the Delta wave, Beta wave, and the sensory motor rhythm were showed significant effects between the groups. [Conclusion] It is thought that neurofeedback training, a training approach to self-regulate brain waves, enhances concentration and relaxation without stress, as well as an increase in attention, memory, and verbal cognitive performance. Therefore an effective intervention method to improve neck pain and daily activities. PMID:27821966

Functional Neuroanatomy for Posture and Gait Control

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Kaoru Takakusaki

2017-01-01

Full Text Available Here we argue functional neuroanatomy for posture- gait control. Multi-sensory information such as somatosensory, visual and vestibular sensation act on various areas of the brain so that adaptable posture- gait control can be achieved. Automatic process of gait, which is steady-state stepping movements associating with postural reflexes including headeye coordination accompanied by appropriate alignment of body segments and optimal level of postural muscle tone, is mediated by the descending pathways from the brainstem to the spinal cord. Particularly, reticulospinal pathways arising from the lateral part of the mesopontine tegmentum and spinal locomotor network contribute to this process. On the other hand, walking in unfamiliar circumstance requires cognitive process of postural control, which depends on knowledges of self-body, such as body schema and body motion in space. The cognitive information is produced at the temporoparietal association cortex, and is fundamental to sustention of vertical posture and construction of motor programs. The programs in the motor cortical areas run to execute anticipatory postural adjustment that is optimal for achievement of goal-directed movements. The basal ganglia and cerebellum may affect both the automatic and cognitive processes of posturegait control through reciprocal connections with the brainstem and cerebral cortex, respectively. Consequently, impairments in cognitive function by damages in the cerebral cortex, basal ganglia and cerebellum may disturb posture-gait control, resulting in falling.

Postural stability and occlusal status among Japanese elderly.

Science.gov (United States)

Song-Yu, Xuan; Rodis, Omar M M; Ogata, Sagiri; Can-Hu, Jin; Nishimura, Michiko; Matsumura, Seishi

2012-06-01

There are still no data available on the relationship between postural stability and occlusal status among the elderly. To examine relationships between postural stability and occlusal status through a cohort study among elderly Japanese. Oral examination, occlusal status, postural stability and a questionnaire were conducted and given to 87 community-dwelling Japanese at enrolment. The average occlusal pressure of the female group was statistically higher than the male group while average occlusal pressure and postural stability length were lesser in the group with more remaining teeth. Postural stability area and number of remaining teeth showed statistically significant correlations. Postural stability length was lesser in the group with strong occlusal force. Furthermore, the number of decayed teeth was fewer in the good hygiene group. This study identified a close relationship between occlusal status and postural stability of Japanese older individuals. Occlusal hypofunction was observed more in those with occlusal problems, and a decrease in their occlusal functions resulted in postural instability. © 2011 The Gerodontology Society and John Wiley & Sons A/S.

Postural Stability of Patients with Schizophrenia during Challenging Sensory Conditions: Implication of Sensory Integration for Postural Control.

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Ya-Ling Teng

Full Text Available Postural dysfunctions are prevalent in patients with schizophrenia and affect their daily life and ability to work. In addition, sensory functions and sensory integration that are crucial for postural control are also compromised. This study intended to examine how patients with schizophrenia coordinate multiple sensory systems to maintain postural stability in dynamic sensory conditions. Twenty-nine patients with schizophrenia and 32 control subjects were recruited. Postural stability of the participants was examined in six sensory conditions of different level of congruency of multiple sensory information, which was based on combinations of correct, removed, or conflicting sensory inputs from visual, somatosensory, and vestibular systems. The excursion of the center of pressure was measured by posturography. Equilibrium scores were derived to indicate the range of anterior-posterior (AP postural sway, and sensory ratios were calculated to explore ability to use sensory information to maintain balance. The overall AP postural sway was significantly larger for patients with schizophrenia compared to the controls [patients (69.62±8.99; controls (76.53±7.47; t1,59 = -3.28, p<0.001]. The results of mixed-model ANOVAs showed a significant interaction between the group and sensory conditions [F5,295 = 5.55, p<0.001]. Further analysis indicated that AP postural sway was significantly larger for patients compared to the controls in conditions containing unreliable somatosensory information either with visual deprivation or with conflicting visual information. Sensory ratios were not significantly different between groups, although small and non-significant difference in inefficiency to utilize vestibular information was also noted. No significant correlations were found between postural stability and clinical characteristics. To sum up, patients with schizophrenia showed increased postural sway and a higher rate of falls during challenging sensory

What happens to the triangular fibrocartilage complex during pronation and supination of the forearm? Analysis of its morphology and diagnostic assessment with MR arthrography

Energy Technology Data Exchange (ETDEWEB)

Pfirrmann, C.W.A. [Dept. of Radiology, Veterans Administration Medical Center, San Diego, CA (United States); Dept. of Radiology, Orthopedic University Hospital Balgrist, Zurich (Switzerland); Theumann, N.H. [Dept. of Radiology, Veterans Administration Medical Center, San Diego, CA (United States); Service de Radiologie, CHUV, Lausanne (Switzerland); Chung, C.B.; Trudell, D.J.; Resnick, D. [Dept. of Radiology, Veterans Administration Medical Center, San Diego, CA (United States); Botte, M.J. [Div. of Orthopedic Surgery, Scripps Clinic and Research Foundation, La Jolla, CA (United States)

2001-12-01

Objective: To evaluate the dynamic morphologic changes of the triangular fibrocartilage complex (TFCC) during pronation and supination of the forearm using high-resolution MR arthrography in cadavers and to evaluate the impact of these changes on the diagnostic assessment of the normal and abnormal TFCC. Design and specimens: High-resolution MR arthrography of 10 wrists of cadaveric specimens was obtained in maximum pronation, in the neutral position, and in maximum supination of the forearm. The structures of the TFCC were evaluated by two musculoskeletal radiologists and correlated with anatomic sections. The position of the forearm that allowed the best visualization of normal structures and lesions of the TFCC was determined. Results: The shape and extent of the articular disc as well as the radial portions of the radioulnar ligaments did not change with pronation and supination. The articular disc was horizontal in the neutral position and tilted more distally to align with the proximal carpal row in pronation and supination. The fibers of the ulnar part of the radioulnar ligaments (ulnar attachment of the articular disc) revealed the most significant changes: their orientation was coronal in the neutral position and sagittal in positions of pronation and supination. The ulnomeniscal homologue was largest in the neutral position and was reduced in size during pronation and supination. The extensor carpi ulnaris tendon was centered in its groove in the neutral position and pronation. In supination this tendon revealed subluxation from this groove. The dorsal capsule of the distal radioulnar joint was taut in pronation, and the palmar capsule was taut in supination. The preferred forearm position for analysis of most of the structures of the TFCC was the neutral position, followed by the pronated position. The neutral position was rated best for the detection of ulnar and radial detachments of the TFCC, followed by the pronated position, except for two central

Cinerama sickness and postural instability.

Science.gov (United States)

Bos, Jelte E; Ledegang, Wietse D; Lubeck, Astrid J A; Stins, John F

2013-01-01

Motion sickness symptoms and increased postural instability induced by motion pictures have been reported in a laboratory, but not in a real cinema. We, therefore, carried out an observational study recording sickness severity and postural instability in 19 subjects before, immediately and 45 min after watching a 1 h 3D aviation documentary in a cinema. Sickness was significantly larger right after the movie than before, and in a lesser extent still so after 45 min. The average standard deviation of the lateral centre of pressure excursions was significantly larger only right afterwards. When low-pass filtered at 0.1 Hz, lateral and for-aft excursions were both significantly larger right after the movie, while for-aft excursions then remained larger even after 45 min. Speculating on previous findings, we predict more sickness and postural instability in 3D than in 2D movies, also suggesting a possible, but yet unknown risk for work-related activities and vehicle operation. Watching motion pictures may be sickening and posturally destabilising, but effects in a cinema are unknown. We, therefore, carried out an observational study showing that sickness then is mainly an issue during the exposure while postural instability is an issue afterwards.

Anthropometric Renal Anatomic Alterations Between Supine and Prone Positions in Percutaneous Renal Ablation for Renal Cortical Neoplasms.

Science.gov (United States)

Lusch, Achim; Fujimoto, Scott; Findeiss, Laura K; Okhunov, Zhamshid; McDougall, Elspeth M; Landman, Jaime

2016-02-01

To establish patterns of anatomic changes relevant to the kidney and colon during positional change between the supine and prone positions as noted on CT scans performed during percutaneous cryoablation for renal cortical neoplasms (RCN). Nineteen patients undergoing percutaneous cryoablation for RCN with abdominal CT scan in both the supine and prone positions were included in the study. We documented the anterior/posterior, medial/lateral, and cranial/caudal anatomic changes of the kidney, kidney rotation, and the proportion of the kidney whose access was limited by the liver, spleen, and lung. We also calculated the length of the percutaneous access tract and the distance between the colon and kidney in hilar position as well as the anterior/posterior location of the colon relative to the kidney. In the prone position, the kidney lies significantly more anteriorly on both sides: 4.7 cm vs 4.3 cm (L) and 4.4 cm vs 4.1 cm (R) (p = 0.02 and p = 0.03, respectively). On prone CT images, both kidneys are more cranial when compared with the supine position: 80.4 mm vs 60.8 mm (L) and 87.2 mm vs 57.4 mm (R) (p = 0.002 and p anatomic alterations between supine and prone CT imaging. The changes associated with the prone position modify percutaneous access, particularly for right upper pole tumors. Prone imaging before surgery may be helpful in selected cases.

Target volume shape variation during irradiation of rectal cancer patients in supine position: Comparison with prone position

International Nuclear Information System (INIS)

Nijkamp, Jasper; Jong, Rianne de; Sonke, Jan-Jakob; Vliet, Corine van; Marijnen, Corrie

2009-01-01

Purpose: To quantify the inter-fraction shape variation of the mesorectum for rectal cancer patients treated with 5 x 5 Gy in supine position and compare it to variation in prone position. Methods and materials: For 28 patients a planning CT (pCT) and five daily cone-beam-CT (CBCT) scans were acquired in supine position. The mesorectal part of the CTV (MesoRect) was delineated on all scans. The shape variation was quantified by the distance between the pCT- and the CBCT delineations and stored in surface maps after online setup correction. Data were analyzed for male and female patients separately and compared to prone data. Results: A large range of systematic, 1-8 mm (1SD), and random, 1-5 mm, shape variation was found, comparable to prone patients. Random-shape variation was comparable for male and female patients, while systematic variation was 3 mm larger for female patients. Conclusions: Shape variation of the MesoRect is substantial, heterogeneous and different between male and female patients. Differences between supine and prone orientation, however, are small. Clinical margins should be differentiated in position along the cranio-caudal axis, in anterior-posterior direction and for gender. Margins should also be increased, even when online setup correction is used. Due to the small margin differences between prone and supine treatments, the setup choice should be determined on dose to the organs at risk.

Registration of central paths and colonic polyps between supine and prone scans in computed tomography colonography: Pilot study

International Nuclear Information System (INIS)

Li Ping; Napel, Sandy; Acar, Burak; Paik, David S.; Jeffrey, R. Brooke Jr.; Beaulieu, Christopher F.

2004-01-01

Computed tomography colonography (CTC) is a minimally invasive method that allows the evaluation of the colon wall from CT sections of the abdomen/pelvis. The primary goal of CTC is to detect colonic polyps, precursors to colorectal cancer. Because imperfect cleansing and distension can cause portions of the colon wall to be collapsed, covered with water, and/or covered with retained stool, patients are scanned in both prone and supine positions. We believe that both reading efficiency and computer aided detection (CAD) of CTC images can be improved by accurate registration of data from the supine and prone positions. We developed a two-stage approach that first registers the colonic central paths using a heuristic and automated algorithm and then matches polyps or polyp candidates (CAD hits) by a statistical approach. We evaluated the registration algorithm on 24 patient cases. After path registration, the mean misalignment distance between prone and supine identical anatomic landmarks was reduced from 47.08 to 12.66 mm, a 73% improvement. The polyp registration algorithm was specifically evaluated using eight patient cases for which radiologists identified polyps separately for both supine and prone data sets, and then manually registered corresponding pairs. The algorithm correctly matched 78% of these pairs without user input. The algorithm was also applied to the 30 highest-scoring CAD hits in the prone and supine scans and showed a success rate of 50% in automatically registering corresponding polyp pairs. Finally, we computed the average number of CAD hits that need to be manually compared in order to find the correct matches among the top 30 CAD hits. With polyp registration, the average number of comparisons was 1.78 per polyp, as opposed to 4.28 comparisons without polyp registration

Increased alertness, better than posture prioritization, explains dual-task performance in prosthesis users and controls under increasing postural and cognitive challenge.

Science.gov (United States)

Howard, Charla L; Perry, Bonnie; Chow, John W; Wallace, Chris; Stokic, Dobrivoje S

2017-11-01

Sensorimotor impairments after limb amputation impose a threat to stability. Commonly described strategies for maintaining stability are the posture first strategy (prioritization of balance) and posture second strategy (prioritization of concurrent tasks). The existence of these strategies was examined in 13 below-knee prosthesis users and 15 controls during dual-task standing under increasing postural and cognitive challenge by evaluating path length, 95% sway area, and anterior-posterior and medial-lateral amplitudes of the center of pressure. The subjects stood on two force platforms under usual (hard surface/eyes open) and difficult (soft surface/eyes closed) conditions, first alone and while performing a cognitive task without and then with instruction on cognitive prioritization. During standing alone, sway was not significantly different between groups. After adding the cognitive task without prioritization instruction, prosthesis users increased sway more under the dual-task than single-task standing (p ≤ 0.028) during both usual and difficult conditions, favoring the posture second strategy. Controls, however, reduced dual-task sway under a greater postural challenge (p ≤ 0.017), suggesting the posture first strategy. With prioritization of the cognitive task, sway was unchanged or reduced in prosthesis users, suggesting departure from the posture second strategy, whereas controls maintained the posture first strategy. Individual analysis of dual tasking revealed that greater postural demand in controls and greater cognitive challenge in prosthesis users led to both reduced sway and improved cognitive performance, suggesting cognitive-motor facilitation. Thus, activation of additional resources through increased alertness, rather than posture prioritization, may explain dual-task performance in both prosthesis users and controls under increasing postural and cognitive challenge.

Postural adjustments are modulated by manual task complexity

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Luis Augusto Teixeira

2009-09-01

Full Text Available Daily life activities of humans are characterized by dual tasks, in which a manual task is performed concomitantly with a postural task. Based on the assumption that both manual and postural tasks require attentional resources, no consensus exists as to how the central nervous system modulates postural adjustments in dual tasks. The aim of the present study was to analyze the effect of a manual task requiring attentional resources on shoulder and ankle adjustments as a function of the direction and predictability of postural perturbation. The participants (n=6 were evaluated during the performance of a simple and a complex manual task, while the base of support was moved backward or forward. Latency of activation of the tibialis anterior and gastroc-nemius muscles and angular acceleration of the shoulder were analyzed. The results showed that execution of the complex manual task delayed postural adjustment. Moreover, this delay occurred differently depending on the direction of postural perturbation. The delay in postural adjustment occurred proximally in the case of anterior displacement of the platform, and distally in the case of posterior displacement. Postural adjustments were more affected by the attentional task than by the predictability of platform displacement. These results are consistent with the concept of an integrated control between manual actions and the maintenance of static posture.

The effects of brief swaying on postural control.

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Pagé, Sara; Maheu, Maxime; Landry, Simon P; Champoux, François

2017-12-06

Postural control can be improved with balance training. However, the nature and duration of the training required to enhance posture remains unclear. We studied the effects of 5 min of a self-initiated balance exercise along a single axis on postural control in healthy individuals. Postural control was measured before and after a 5-min period where members of the experimental group were asked to lean their entire body forward and backward and members of the control group were asked to remain seated. A significant improvement for sway velocity, a postural control variable significantly associated with an increased risk of falls, was found in the experimental group following the body sway exercise. These data suggest that a basic exercise can rapidly improve postural control and reduce the risk of falls.

Associations between vertebral fractures, increased thoracic kyphosis, a flexed posture and falls in older adults: a prospective cohort study.

Science.gov (United States)

van der Jagt-Willems, Hanna C; de Groot, Maartje H; van Campen, Jos P C M; Lamoth, Claudine J C; Lems, Willem F

2015-03-28

Vertebral fractures, an increased thoracic kyphosis and a flexed posture are associated with falls. However, this was not confirmed in prospective studies. We performed a prospective cohort study to investigate the association between vertebral fractures, increased thoracic kyphosis and/or flexed posture with future fall incidents in older adults within the next year. Patients were recruited at a geriatric outpatient clinic. Vertebral fractures were evaluated on lateral radiographs of the spine with the semi-quantitative method of Genant; the degree of thoracic kyphosis was assessed with the Cobb angle. The occiput-to-wall distance was used to determine a flexed posture. Self-reported falls were prospectively registered by monthly phone contact for the duration of 12 months. Fifty-one older adults were included; mean age was 79 years (SD = 4.8). An increased thoracic kyphosis was independently associated with future falls (OR 2.13; 95% CI 1.10-4.51). Prevalent vertebral fractures had a trend towards significancy (OR 3.67; 95% CI 0.85-15.9). A flexed posture was not significantly associated with future falls. Older adults with an increased thoracic kyphosis are more likely to fall within the next year. We suggest clinical attention for underlying causes. Because patients with increased thoracic curvature of the spine might have underlying osteoporotic vertebral fractures, clinicians should be aware of the risk of a new fracture.

Periodic upright posture negates the suppression of neuroendocrine response to head down bedrest

Science.gov (United States)

Wade, C. E.; Vernikos, J.; Evans, J.; Ohara, D.

1992-01-01

Head down bedrest (HDT) decreases plasma neurohormone levels, attaining a nadir within four hours. The present study evaluates the effect of periodic standing or exercises (+G(z)) on this acute suppression of plasma neurohormones. Methods: Nine male subjects (mean plus or minus SE age 37 plus or minus 2 yr; height 182 plus or minus 2 cm; weight 83 plus or minus 3 kg) were admitted to the Human Research Facility on three occasions separated by one month. Subjects were assigned to head down tilt (minus 6 degrees) or 15-minutes of standing or moderate exercise at the end of each hour. Initially during an ambulatory period, subjects were placed in a supine position for 45-min and a control blood sample obtained. The next day following 4 hours of HDT with or without standing or exercise a blood sample was taken 45-min (3 3/4 hours into HDT) after the preceding stand or exercise. Blood was withdrawn and all plasma samples frozen for determination of neurohormone levels within the same assay. Plasma aldosterone, Plasma Renin Activity (PRA) vasopressin (AVP) and cortisol levels were measured by radioimmunoassay. Norepinephrine (NE) and epinephrine (E) levels were measured by electrochemical detection following HPLC. Values were compared by ANOVA, P less than 0.05. Results: Control levels following 45-min supine were not different between treatments. HDT suppressed plasma aldosterone (13.9 plus or minus 3.7 to 6.6 plus or minus 0.7 ng/dl) and NE levels (299 plus or minus 35 to 217 plus or minus 23 pg/dl), E (69 plus or minus 15 to 65 plus or minus 21 pg/ml), and PRA (0.64 plus or minus 0.13 to 0.58 plus or minus 0.17 ngAl/m/hr) were not significantly altered. Standing or exercise negated the decrease in aldosterone and NE levels due to HDT. Conclusions: Periodic upright posture (+G(z)) with or without exercise for 15-min out of each hour negates the acute suppression of aldosterone and NE associated with HDT.

Activation timing of postural muscles of lower legs and prediction of postural disturbance during bilateral arm flexion in older adults.

Science.gov (United States)

Yaguchi, Chie; Fujiwara, Katsuo; Kiyota, Naoe

2017-12-22

Activation timings of postural muscles of lower legs and prediction of postural disturbance were investigated in young and older adults during bilateral arm flexion in a self-timing task and an oddball task with different probabilities of target presentation. Arm flexion was started from a standing posture with hands suspended 10 cm below the horizontal level in front of the body, in which postural control focused on the ankles is important. Fourteen young and 14 older adults raised the arms in response to the target sound signal. Three task conditions were used: 15 and 45% probabilities of the target in the oddball task and self-timing. Analysis items were activation timing of postural muscles (erector spinae, biceps femoris, and gastrocnemius) with respect to the anterior deltoid (AD), and latency and amplitude of the P300 component of event-related brain potential. For young adults, all postural muscles were activated significantly earlier than AD under each condition, and time of preceding gastrocnemius activation was significantly longer in the order of the self-timing, 45 and 15% conditions. P300 latency was significantly shorter, and P300 amplitude was significantly smaller under the 45% condition than under the 15% condition. For older adults, although all postural muscles, including gastrocnemius, were activated significantly earlier than AD in the self-timing condition, only activation timing of gastrocnemius was not significantly earlier than that of AD in oddball tasks, regardless of target probability. No significant differences were found between 15 and 45% conditions in onset times of all postural muscles, and latency and amplitude of P300. These results suggest that during arm movement, young adults can achieve sufficient postural preparation in proportion to the probability of target presentation in the oddball task. Older adults can achieve postural control using ankle joints in the self-timing task. However, in the oddball task, older adults

Effect of reducing abdominal compression during prone CT colonography on ascending colonic rotation during supine-to-prone positional change

International Nuclear Information System (INIS)

Jang, Jong eon; Park, Seong Ho; Lee, Jong Seok; Kim, Hyun Jin; KIm, Ah Young; Ha, Hyun Kwon

2016-01-01

To determine the effect of reduced abdominal compression in prone position on ascending colonic movement during supine-to-prone positional change during CT colonography (CTC). Eighteen consecutive patients who had undergone prone CTC scanning with cushion blocks placed under the chest and hip/thigh to reduce abdominal compression and had confirmed sessile polyps ≥ 6 mm in the well-distended, straight, mid-ascending colon, were included. Radial location along the ascending colonic luminal circumference (°) was measured for 24 polyps and 54 colonic teniae on supine and prone CTC images. The supine-to-prone change ranging between -180° and +180° (- and + for internal and external colonic rotations, respectively), was determined. In addition, possible causes of any ascending colonic rotations were explored. Abdominal compression during prone CTC scanning completely disappeared with the use of cushion blocks in 17 of 18 patients. However, some degrees of ascending colonic rotation were still observed, with the radial location changes of -22° to 61° (median, 13.9°) for the polyps and similar degrees for teniae. Fifty-four percent and 56% of polyps and teniae, respectively, showed changes > 10°. The radial location change of the polyps was significantly associated with the degree of anterior shift of the small bowel and mesentery (r = 0.722, p < 0.001) and the degree of posterior displacement of the ascending colon (r = 0.566, p = 0.004) during supine-to-prone positional change. Ascending colonic rotation upon supine-to-prone positional change during CTC, mostly in the form of external rotation, is not eliminated by removing abdominal compression in prone position

Neuromechanical tuning of nonlinear postural control dynamics

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Ting, Lena H.; van Antwerp, Keith W.; Scrivens, Jevin E.; McKay, J. Lucas; Welch, Torrence D. J.; Bingham, Jeffrey T.; DeWeerth, Stephen P.

2009-06-01

Postural control may be an ideal physiological motor task for elucidating general questions about the organization, diversity, flexibility, and variability of biological motor behaviors using nonlinear dynamical analysis techniques. Rather than presenting "problems" to the nervous system, the redundancy of biological systems and variability in their behaviors may actually be exploited to allow for the flexible achievement of multiple and concurrent task-level goals associated with movement. Such variability may reflect the constant "tuning" of neuromechanical elements and their interactions for movement control. The problem faced by researchers is that there is no one-to-one mapping between the task goal and the coordination of the underlying elements. We review recent and ongoing research in postural control with the goal of identifying common mechanisms underlying variability in postural control, coordination of multiple postural strategies, and transitions between them. We present a delayed-feedback model used to characterize the variability observed in muscle coordination patterns during postural responses to perturbation. We emphasize the significance of delays in physiological postural systems, requiring the modulation and coordination of both the instantaneous, "passive" response to perturbations as well as the delayed, "active" responses to perturbations. The challenge for future research lies in understanding the mechanisms and principles underlying neuromechanical tuning of and transitions between the diversity of postural behaviors. Here we describe some of our recent and ongoing studies aimed at understanding variability in postural control using physical robotic systems, human experiments, dimensional analysis, and computational models that could be enhanced from a nonlinear dynamics approach.

Obesity impact on the attentional cost for controlling posture.

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Jean-Baptiste Mignardot

2010-12-01

Full Text Available This study investigated the effects of obesity on attentional resources allocated to postural control in seating and unipedal standing.Ten non obese adults (BMI = 22.4±1.3, age = 42.4±15.1 and 10 obese adult patients (BMI = 35.2±2.8, age = 46.2±19.6 maintained postural stability on a force platform in two postural tasks (seated and unipedal. The two postural tasks were performed (1 alone and (2 in a dual-task paradigm in combination with an auditory reaction time task (RT. Performing the RT task together with the postural one was supposed to require some attentional resources that allowed estimating the attentional cost of postural control. 4 trials were performed in each condition for a total of 16 trials.(1 Whereas seated non obese and obese patients exhibited similar centre of foot pressure oscillations (CoP, in the unipedal stance only obese patients strongly increased their CoP sway in comparison to controls. (2 Whatever the postural task, the additional RT task did not affect postural stability. (3 Seated, RT did not differ between the two groups. (4 RT strongly increased between the two postural conditions in the obese patients only, suggesting that body schema and the use of internal models was altered with obesity.Obese patients needed more attentional resources to control postural stability during unipedal stance than non obese participants. This was not the case in a more simple posture such as seating. To reduce the risk of fall as indicated by the critical values of CoP displacement, obese patients must dedicate a strong large part of their attentional resources to postural control, to the detriment of non-postural events. Obese patients were not able to easily perform multitasking as healthy adults do, reflecting weakened psycho-motor abilities.

Obesity Impact on the Attentional Cost for Controlling Posture

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Mignardot, Jean-Baptiste; Olivier, Isabelle; Promayon, Emmanuel; Nougier, Vincent

2010-01-01

Background This study investigated the effects of obesity on attentional resources allocated to postural control in seating and unipedal standing. Methods Ten non obese adults (BMI = 22.4±1.3, age = 42.4±15.1) and 10 obese adult patients (BMI = 35.2±2.8, age = 46.2±19.6) maintained postural stability on a force platform in two postural tasks (seated and unipedal). The two postural tasks were performed (1) alone and (2) in a dual-task paradigm in combination with an auditory reaction time task (RT). Performing the RT task together with the postural one was supposed to require some attentional resources that allowed estimating the attentional cost of postural control. 4 trials were performed in each condition for a total of 16 trials. Findings (1) Whereas seated non obese and obese patients exhibited similar centre of foot pressure oscillations (CoP), in the unipedal stance only obese patients strongly increased their CoP sway in comparison to controls. (2) Whatever the postural task, the additional RT task did not affect postural stability. (3) Seated, RT did not differ between the two groups. (4) RT strongly increased between the two postural conditions in the obese patients only, suggesting that body schema and the use of internal models was altered with obesity. Interpretation Obese patients needed more attentional resources to control postural stability during unipedal stance than non obese participants. This was not the case in a more simple posture such as seating. To reduce the risk of fall as indicated by the critical values of CoP displacement, obese patients must dedicate a strong large part of their attentional resources to postural control, to the detriment of non-postural events. Obese patients were not able to easily perform multitasking as healthy adults do, reflecting weakened psycho-motor abilities. PMID:21187914

Dual task interference on postural sway, postural transitions and gait in people with Parkinson's disease and freezing of gait.

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de Souza Fortaleza, Ana Claudia; Mancini, Martina; Carlson-Kuhta, Patty; King, Laurie A; Nutt, John G; Chagas, Eliane Ferrari; Freitas, Ismael Forte; Horak, Fay B

2017-07-01

Freezing of gait (FoG) is associated with less automatic gait and more impaired cognition, balance and postural transitions compared to people with PD who do not have FoG. However, it is unknown whether dual-task cost during postural sway, postural transitions (such as gait initiation and turning), and gait are more in subjects with Parkinson's disease (PD) who have freezing of gait (FoG+) compared to those who do not have FoG (FoG-). Here, we hypothesized that the effects of a cognitive dual task on postural sway, postural transitions and gait would be larger in FoG+ than FoG-. Thirty FoG- and 24 FoG+ performed an Instrumented Stand and Walk test in OFF medication state, with and without a secondary cognitive task (serial subtraction by 3s). Measures of postural sway, gait initiation, turning, and walking were extracted using body-worn inertial sensors. FoG+ showed significantly larger dual task cost than FoG- for several gait metrics, but not during postural sway or postural transitions. During walking, FoG+ exhibited a larger dual task cost than FoG- resulting in shorter stride length and slower stride velocity. During standing, FoG+ showed a larger postural sway compared to FoG- and during gait initiation, FoG+, but not FoG-, showed a longer first step duration during the dual-task condition compared to single-task condition (interaction effect, p=0.04). During turning, both groups showed a slower turn peak speed in the dual-task condition compared to single task condition. These findings partly support our hypothesis that dual task cost on walking is greater in FoG+ than FoG-. Copyright © 2017. Published by Elsevier B.V.

A flexed posture in elderly patients is associated with impairments in postural control during walking.

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de Groot, Maartje H; van der Jagt-Willems, Hanna C; van Campen, Jos P C M; Lems, Willem F; Beijnen, Jos H; Lamoth, Claudine J C

2014-02-01

A flexed posture (FP) is characterized by protrusion of the head and an increased thoracic kyphosis (TK), which may be caused by osteoporotic vertebral fractures (VFs). These impairments may affect motor function, and consequently increase the risk of falling and fractures. The aim of the current study was therefore to examine postural control during walking in elderly patients with FP, and to investigate the relationship with geriatric phenomena that may cause FP, such as increased TK, VFs, frailty, polypharmacy and cognitive impairments. Fifty-six elderly patients (aged 80 ± 5.2 years; 70% female) walked 160 m at self-selected speed while trunk accelerations were recorded. Walking speed, mean stride time and coefficient of variation (CV) of stride time were recorded. In addition, postural control during walking was quantified by time-dependent variability measures derived from the theory of stochastic dynamics, indicating smoothness, degree of predictability, and local stability of trunk acceleration patterns. Twenty-five patients (45%) had FP and demonstrated a more variable and less structured gait pattern, and a more irregular trunk acceleration pattern than patients with normal posture. FP was significantly associated with an increased TK, but not with other geriatric phenomena. An increased TK may bring the body's centre of mass forward, which requires correcting responses, and reduces the ability to respond on perturbation, which was reflected by higher variation in the gait pattern in FP-patients. Impairments in postural control during walking are a major risk factor for falling: the results indicate that patients with FP have impaired postural control during walking and might therefore be at increased risk of falling. Copyright © 2013 Elsevier B.V. All rights reserved.

The dentist’s operating posture – ergonomic aspects

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Pîrvu, C; Pătraşcu, I; Pîrvu, D; Ionescu, C

2014-01-01

Abstract The practice of dentistry involves laborious high finesse dental preparations, precision and control in executions that require a particular attention, concentration and patience of the dentist and finally the dentist’s physical and mental resistance. The optimal therapeutic approach and the success of practice involve special working conditions for the dentist and his team in an ergonomic environment. The meaning of the posture in ergonomics is the manner in which different parts of the body are located and thus the reports are established between them in order to allow a special task execution. This article discusses the posture adopted by dentists when they work, beginning with the balanced posture and going to different variants of posture. The ideal posture of a dentist gives him, on the one hand the optimal working conditions (access, visibility and control in the mouth) and on the other hand, physical and psychological comfort throughout the execution of the clinical acts. Although the theme of dentist posture is treated with great care and often presented in the undergraduate courses and the continuing education courses on ergonomics in dentistry, many dentists do not know the subject well enough nor the theoretical issues and therefore nor the practical applicability. The risk and perspective of the musculoskeletal disorders related to unbalanced postures should determine the dentists take postural corrective actions and compensation measures in order to limit the negative effects of working in a bad posture. PMID:25184007

USE OF SOFTWARES FOR POSTURE ASSESSMENT: INTEGRATIVE REVIEW

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Edyla Maria Porto de Freitas Camelo

2015-09-01

Full Text Available To carry out an integrative literature review on the postural analysis softwares available today. It is an integrative-narrative review of qualitative and methodological nature performed during April-July 2014. As inclusion criteria, the articles should be bibliographical or original research and available with full access. At first, we proceeded to the identification of the keywords for the softwares related to postural assessment commonly used in the health field, in such case "posture", "software", and "postural assessment". The search was narrowed by publication date from 2002 to 2014. Through the information acquired from the articles and from the software developers, information on 12 programs that assist the postural evaluation were obtained - Alcimage, All Body Scan 3D, Aplob, APPID, Biotonix, Corporis Pro, Fisimetrix, Fisiometer Posturograma, Physical Fisio, Physio Easy, Posture Print and SAPO. However, only one tool has more information and studies, namely SAPO. There are many postural analysis softwares available on the internet today, however, these are quite disparate in relation to possible answers and are still poorly widespread as research tools.

Effect of Temper Condition on Stress Relaxation Behavior of an Aluminum Copper Lithium Alloy

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Mishra, Sumeet; Beura, Vikrant Kumar; Singh, Amit; Yadava, Manasij; Nayan, Niraj

2018-04-01

Deformation behavior of an Al-Cu-Li alloy in different temper conditions (solutionized and T8) is investigated using stress relaxation tests. Fundamental parameters such as the apparent and physical activation volume, strain rate sensitivity, effective stress, and exhaustion rate of mobile dislocation density are determined from single and multiple relaxation tests. It was found that dislocation-dislocation interaction controls the kinetics of plastic deformation in the solutionized sample, whereas dislocation-precipitate interaction is the overriding factor in the presence of T1 precipitates. The apparent activation volume was found to be significantly lower in the presence of T1 precipitates compared with solutionized samples. Strain rate sensitivity and effective stress were found to be higher in the presence of T1 precipitates. In addition, multiple relaxation tests showed that irrespective of microstructural features (solutes, semi-coherent precipitates), the mobile dislocation density reduces during the relaxation period. Further evidence regarding reduction in mobile dislocation density is obtained from uniaxial tensile tests carried out after stress relaxation tests, where both solutionized and T8 samples show an increase in strength. Additional discussion on relaxation strain is included to provide a complete overview regarding the time-dependent deformation behavior of the Al-Cu-Li alloy in different temper conditions.

Riscos biomecânicos posturais em trabalhadores de uma serraria Biomechanical risks in sawmill worker postures

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André Gustavo Soares de Oliveira

2009-03-01

Full Text Available Os trabalhadores em serrarias estão sujeitos a riscos biomecânicos advindos das posturas adotadas durante suas atividades laborais. Este trabalho visou avaliar as posturas adotadas por esses trabalhadores por meio do método de avaliação rápida do corpo inteiro (REBA, rapid entire body assessment, buscando detectar e classificar os riscos biomecânicos. Participaram 15 trabalhadores do setor de produção de uma serraria em João Pessoa, PB, do sexo masculino, com idade média de 44±10,9, avaliando-se quatro posturas: flexão anterior do tronco com levantamento de carga, agachamento profundo, flexão ântero-lateral do tronco e corpo estendido para mover uma prensa. Sintomas musculoesqueléticos foram identificados no mapa corporal de Corlett. Um questionário semi-estruturado levantou os dados demográficos, ambientais e as funções executadas. Pelo REBA, a flexão anterior de tronco apresentou nível de risco muito alto e as posturas de agachamento profundo, flexão ântero-lateral do tronco e movimento do corpo em extensão, nível de risco alto. Uma alta proporção (73,3% deles queixaram-se de dor ou desconforto na coluna e 26,8% na região dos ombros. Considerando os níveis de riscos apresentados, requerem-se intervenções ergonômicas preventivas no posto de trabalho para adoção de posturas que melhor propiciem a execução das atividades com menor risco à saúde do trabalhador.Workers in sawmills are exposed to biomechanical risks due to the postures adopted during their activities. The purpose here was to assess postures adopted by these workers by using the rapid entire body assessment (REBA, in order to detect and classify possible biomechanical risks. Fifteen male workers from the production section of a sawmill in João Pessoa, PB (mean age 44±10.9 years old were assessed as to the postures adopted at work. A semi-structured questionnaire collected demographic and environmental data as well as functions in the workplace

The association of antihypertensives with postural blood pressure and falls among seniors residing in the community: a case-control study.

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Zia, Anam; Kamaruzzaman, Shahrul B; Myint, Phyo K; Tan, Maw P

2015-10-01

A drop in postural blood pressure (BP) may contribute to falls, while antihypertensives have been considered to induce postural drop or orthostatic hypotension (OH) and falls among older people. However, this relationship between antihypertensives, postural BP and the risk of falls has never been evaluated in a single study. To examine the association of postural BP changes and BP therapy with the risk of falls among community-dwelling older people in a case-control manner. Cases (n = 202) included participants aged ≥ 65 years with two falls or one injurious fall while controls (n = 156) included participants ≥ 65 years with no falls in the preceding 12 months. Antihypertensives usage and medical history were recorded. Supine BP measurements were obtained at 10 min rest and at 1, 2 and 3 min after standing. Orthostatic hypotension was defined as a reduction in BP of 20/10 mmHg within 3 min of standing. Individual antihypertensive classes were not associated with falls. Minimal standing systolic BP (SBP) was significantly lower among fallers [128 (± 27·3) vs. 135·7 (± 24·7) mmHg; P = 0·01], but fallers were not more likely to fulfil the diagnostic criteria for OH. Diuretics were associated with OH and α-blockers were associated with minimal standing SBP. Univariate analysis revealed that the use of ≥ 2 antihypertensives was associated with recurrent and injurious falls [OR,1.97;CI,1.2-3.1], which was no longer significant aftermultivariateadjustment for age and number of comorbidities [OR, 1.6; CI, 0.95-2.6]. Minimal standing SBP or a lower SBP at 2 or 3minutes standing was associated with falls rather than OH using consensus definition. Association between ≥ 2 antihypertensives and falls was attenuated by increasing age and comorbidities. Our findings challenge previous assumptions that OH or the use of antihypertensives is associated with falls. Future studies should now seek to link these findings prospectively with falls in order to guide decision

Effects of rapid maxillary expansion on head posture, postural stability, and fall risk

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Fatih Celebi

2017-01-01

Full Text Available Objective: The aim of this study was to investigate the effects of rapid maxillary expansion (RME on head posture, postural stability, and fall risk. Materials and Methods: A sample of 51 adolescent patients was randomly divided into two groups. In the first group, which consisted of 28 patients (15 females and 13 males, RME was performed as a part of routine orthodontic treatment. The remaining 23 individuals (12 females and 11 males served as the control group. Lateral cephalometric radiographs taken in natural head position, postural stability, and fall risk scores were obtained during the first visit. They were repeated on average 3.8 months and 3.5 months later for the study and control groups, respectively. The changes were analyzed using the Wilcoxon signed-rank test, paired samples t-test, Mann–Whitney U-test, and independent samples t-test. Results: As a result of RME, a statistically significant decrease was detected in the fall risk score (P < 0.05 in the study group, while the head position and postural stability remained unchanged. For the control group, no significant changes were observed in all measurements. Conclusions: The result of the present study suggests that RME has a capacity of improving fall risk.

EFFICACY OF POST ISOMETRIC RELAXATION VERSUS STATIC STRECHING IN SUBJECTS WITH CHRONIC NON SPECIFIC NECK PAIN

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P.Haritha

2015-12-01

Full Text Available Background: Neck pain is a common problem within our society. Upper trapezius sternocleidomastoid and the levator scapulae are the most common postural muscles that tends to get shorten leading to restricted neck mobility. There is lack of evidence to allow conclusions to be drawn about the effectiveness of post isometric relaxation when compared with static stretching exercises. The aim is to find out the effectiveness of Post isometric relaxation Versus Static stretching in the subjects with chronic nonspecific neck pain. To evaluate the effectiveness of post isometric relaxation technique on pain by using Visual analoge scale, range of motion by using Universal Goniometry, and functional disability by using Neck Disability Index in chronic nonspecific neck pain. Methods: A convenient sample of thirty seven subjects was diagnosed with nonspecific neck pain was randomly allocated to one of the two treatment groups on the basis of the inclusion criteria. The experimental group (n=15 received three sessions of post isometric relaxation technique for trapezius, sternocleidomastoid and the levator scapulae and control group (n=15 received the three sessions of static stretching for trapezius, sternocliedomastiod and levator scapulae for four weeks. Results: Non parametric tests demonstrated a statistically significant difference with experimental group showing greater improvement in ROM, VAS, and NDI than the control group and significant difference within the group also. Conclusion: This study concluded and the results reflected that post isometric relaxation technique group had better improvement in reduction of pain, improvement in the range of motion, and increased neck functional activities than the static stretching group.

Variational formulation of relaxed and multi-region relaxed magnetohydrodynamics

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Dewar, R. L.; Yoshida, Z.; Bhattacharjee, A.; Hudson, S. R.

2015-12-01

> Ideal magnetohydrodynamics (IMHD) is strongly constrained by an infinite number of microscopic constraints expressing mass, entropy and magnetic flux conservation in each infinitesimal fluid element, the latter preventing magnetic reconnection. By contrast, in the Taylor relaxation model for formation of macroscopically self-organized plasma equilibrium states, all these constraints are relaxed save for the global magnetic fluxes and helicity. A Lagrangian variational principle is presented that leads to a new, fully dynamical, relaxed magnetohydrodynamics (RxMHD), such that all static solutions are Taylor states but also allows state with flow. By postulating that some long-lived macroscopic current sheets can act as barriers to relaxation, separating the plasma into multiple relaxation regions, a further generalization, multi-region relaxed magnetohydrodynamics (MRxMHD) is developed.

Single-staged uniportal VATS in the supine position for simultaneous bilateral primary spontaneous pneumothorax.

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Kim, Kyung Soo

2017-05-15

Simultaneous bilateral primary spontaneous pneumothorax (SBPSP) is rare, but requires surgery on both sides, in patients with definite bilateral bullae to prevent life-threatening conditions. Recently, uniportal video-assisted thoracoscopic surgery (VATS) has been widely accepted as a less invasive technique for the treatment of pneumothorax. Thus, we introduced single-staged uniportal VATS technique in the supine position, for the management of two cases of SBPSP. A 17-year-old boy presented with bilateral spontaneous pneumothorax and he underwent single-staged uniportal VATS in the supine position. Single wide draping in consecutive bilateral approaches removes the needs of changing patients' position. Whole thoracoscopic procedure for wedge resection of bullae lesions was conducted without difficulty. The total operation time took 65 min and the patient discharged 3 days after the operation. The patient was followed for 24 months without recurrence of both sides. Another 18-year-old boy was admitted with bilateral spontaneous pneumothorax and single-staged uniportal VATS was also performed in the supine position. The total operation time took 79 min and the patient discharged on postoperative day 4. He was followed for 19 months without recurrence of both sides. Single-staged uniportal VATS approach yielded satisfactory results from simplicity that not requires position change compared to conventional multi-ports VATS in the lateral position, and with better cosmetics. This technique is thought to be a feasible procedure in selective patients with SBPSP or with contralateral bullae for preventive role.

[Head posture in orthodontics: physiopathology and clinical aspects 2].

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Caltabiano, M; Verzi, P; Scire Scappuzzo, G

1989-01-01

The Authors review in orthodontic respects present knowledges about head posture involvement in craniofacial morphogenesis and pathology. Relationships between craniofacial morphology, craniocervical posture, craniomandibular posture, cervical spine curvature, hyoid bone position and posture of whole body in space are shown, in attempt to explain conditions such as "forward head posture", mouth breathing and some occlusal disorders. Main methods to evaluate craniocervical relations on lateral skull radiographs are analysed. Pathogenesis of pain syndromes associated with abnormal craniocervical and craniomandibular mechanics are also briefly treated.

Relationship between craniomandibular disorders and poor posture.

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Nicolakis, P; Nicolakis, M; Piehslinger, E; Ebenbichler, G; Vachuda, M; Kirtley, C; Fialka-Moser, V

2000-04-01

The purpose of this research was to show that a relationship between craniomandibular disorders (CMD) and postural abnormalities has been repeatedly postulated, but still remains unproven. This study was intended to test this hypothesis. Twenty-five CMD patients (mean age 28.2 years) were compared with 25 gender and age matched controls (mean age 28.3 years) in a controlled, investigator-blinded trial. Twelve postural and ten muscle function parameters were examined. Measurements were separated into three subgroups, consisting of those variables associated with the cervical region, the trunk in the frontal plane, and the trunk in the sagittal plane. Within these subgroups, there was significantly more dysfunction in the patients, compared to control subjects (Mann-Whitney U test p Postural and muscle function abnormalities appeared to be more common in the CMD group. Since there is evidence of the mutual influence of posture and the craniomandibular system, control of body posture in CMD patients is recommended, especially if they do not respond to splint therapy. Whether poor posture is the reason or the result of CMD cannot be distinguished by the data presented here.

The reliability and validity of the Saliba Postural Classification System.

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Collins, Cristiana Kahl; Johnson, Vicky Saliba; Godwin, Ellen M; Pappas, Evangelos

2016-07-01

To determine the reliability and validity of the Saliba Postural Classification System (SPCS). Two physical therapists classified pictures of 100 volunteer participants standing in their habitual posture for inter and intra-tester reliability. For validity, 54 participants stood on a force plate in a habitual and a corrected posture, while a vertical force was applied through the shoulders until the clinician felt a postural give. Data were extracted at the time the give was felt and at a time in the corrected posture that matched the peak vertical ground reaction force (VGRF) in the habitual posture. Inter-tester reliability demonstrated 75% agreement with a Kappa = 0.64 (95% CI = 0.524-0.756, SE = 0.059). Intra-tester reliability demonstrated 87% agreement with a Kappa = 0.8, (95% CI = 0.702-0.898, SE = 0.05) and 80% agreement with a Kappa = 0.706, (95% CI = 0.594-0818, SE = 0.057). The examiner applied a significantly higher (p < 0.001) peak vertical force in the corrected posture prior to a postural give when compared to the habitual posture. Within the corrected posture, the %VGRF was higher when the test was ongoing vs. when a postural give was felt (p < 0.001). The %VGRF was not different between the two postures when comparing the peaks (p = 0.214). The SPCS has substantial agreement for inter- and intra-tester reliability and is largely a valid postural classification system as determined by the larger vertical forces in the corrected postures. Further studies on the correlation between the SPCS and diagnostic classifications are indicated.

Semidefinite Relaxation-Based Optimization of Multiple-Input Wireless Power Transfer Systems

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Lang, Hans-Dieter; Sarris, Costas D.

2017-11-01

An optimization procedure for multi-transmitter (MISO) wireless power transfer (WPT) systems based on tight semidefinite relaxation (SDR) is presented. This method ensures physical realizability of MISO WPT systems designed via convex optimization -- a robust, semi-analytical and intuitive route to optimizing such systems. To that end, the nonconvex constraints requiring that power is fed into rather than drawn from the system via all transmitter ports are incorporated in a convex semidefinite relaxation, which is efficiently and reliably solvable by dedicated algorithms. A test of the solution then confirms that this modified problem is equivalent (tight relaxation) to the original (nonconvex) one and that the true global optimum has been found. This is a clear advantage over global optimization methods (e.g. genetic algorithms), where convergence to the true global optimum cannot be ensured or tested. Discussions of numerical results yielded by both the closed-form expressions and the refined technique illustrate the importance and practicability of the new method. It, is shown that this technique offers a rigorous optimization framework for a broad range of current and emerging WPT applications.

Relaxation path of metastable nanoclusters in oxide dispersion strengthened materials

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Ribis, J., E-mail: joel.ribis@cea.fr [DEN-Service de Recherches Métallurgiques Appliquées, CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette (France); Thual, M.A. [LLB, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191, Gif-sur-Yvette (France); Guilbert, T.; Carlan, Y. de [DEN-Service de Recherches Métallurgiques Appliquées, CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette (France); Legris, A. [UMET, CNRS/UMR 8207, Bât. C6, Univ. Lille 1, 59655 Villeneuve d’Ascq (France)

2017-02-15

ODS steels are a promising class of structural materials for sodium cooled fast reactor application. The ultra-high density of the strengthening nanoclusters dispersed within the ferritic matrix is responsible of the excellent creep properties of the alloy. Fine characterization of the nanoclusters has been conducted on a Fe-14Cr-0.3Ti-0.3Y{sub 2}O{sub 3} ODS material using High Resolution and Energy Filtered Transmission Electron Microscopy. The nanoclusters exhibit a cubic symmetry possibly identified as f.c.c and display a non-equilibrium YTiCrO chemical composition thought to be stabilized by a vacancy supersaturation. These nanoclusters undergo relaxation towards the Y{sub 2}Ti{sub 2}O{sub 7}-like state as they grow. A Cr shell is observed around the relaxed nano-oxides, this size-dependent shell may form after the release of Cr by the particles. The relaxation energy barrier appears to be higher for the smaller particles probably owing to a volume/surface ratio effect in reason to the full coherency of the nanoclusters. - Highlights: • The nanoclusters display a f.c.c. cubic symmetry and a non-equilibrium YTiCrO chemical composition. • During thermal annealing the coherent nanocluster transform into semi-coherent pyrochlore particles. • A Cr ring is observed around the relaxed pyrochlore type particles.

Registration of prone and supine CT colonography scans using correlation optimized warping and canonical correlation analysis

International Nuclear Information System (INIS)

Wang Shijun; Yao Jianhua; Liu Jiamin; Petrick, Nicholas; Van Uitert, Robert L.; Periaswamy, Senthil; Summers, Ronald M.

2009-01-01

Purpose: In computed tomographic colonography (CTC), a patient will be scanned twice--Once supine and once prone--to improve the sensitivity for polyp detection. To assist radiologists in CTC reading, in this paper we propose an automated method for colon registration from supine and prone CTC scans. Methods: We propose a new colon centerline registration method for prone and supine CTC scans using correlation optimized warping (COW) and canonical correlation analysis (CCA) based on the anatomical structure of the colon. Four anatomical salient points on the colon are first automatically distinguished. Then correlation optimized warping is applied to the segments defined by the anatomical landmarks to improve the global registration based on local correlation of segments. The COW method was modified by embedding canonical correlation analysis to allow multiple features along the colon centerline to be used in our implementation. Results: We tested the COW algorithm on a CTC data set of 39 patients with 39 polyps (19 training and 20 test cases) to verify the effectiveness of the proposed COW registration method. Experimental results on the test set show that the COW method significantly reduces the average estimation error in a polyp location between supine and prone scans by 67.6%, from 46.27±52.97 to 14.98 mm±11.41 mm, compared to the normalized distance along the colon centerline algorithm (p<0.01). Conclusions: The proposed COW algorithm is more accurate for the colon centerline registration compared to the normalized distance along the colon centerline method and the dynamic time warping method. Comparison results showed that the feature combination of z-coordinate and curvature achieved lowest registration error compared to the other feature combinations used by COW. The proposed method is tolerant to centerline errors because anatomical landmarks help prevent the propagation of errors across the entire colon centerline.

Ergonomic strategies to improve radiographers' posture during mammography activities.

Science.gov (United States)

Cernean, Nicolai; Serranheira, Florentino; Gonçalves, Pedro; Sá Dos Reis, Cláudia

2017-08-01

To identify alternatives for radiographers' postures while performing mammography that can contribute to reduce the risk of work-related musculoskeletal disorders (WRMSDs). Radiographers' postures to positioning craniocaudal (CC) and mediolateral oblique (MLO) views were simulated without any intervention for three scenarios: radiographer/patient with similar statures, radiographer smaller than patient and radiographer taller than patient. Actions were taken to modify the postures: seated radiographer; patient on a step; seated patient; radiographer on a step. All the postures were analysed using kinovea 0.8.15 software and the angles were measured twice and classified according to European standard EN1005-4: 2005. The non-acceptable angles were measured mainly during MLO positioning when radiographer was taller than the patient: 139° and 120° for arm-flexion and abduction, 72° for trunk and -24° for head/neck-flexion. The introduction of alternative postures (radiographer seated), allowed improvements in posture (60° and 99° for arm flexion and abduction, 14° for trunk and 0° for head/neck flexion), being classified as acceptable. The alternative postures simulated have the potential to reduce the risk of developing WRMSDs when radiographers and patients have different statures. • Radiographers' postures in mammography can contribute to work-related musculoskeletal disorders • Non-acceptable posture was identified for MLO breast positioning (radiographer taller than patient) • Adapting posture to patient biotype reduces the WRMSD risk for radiographers.

Heart-Rate Variability During Deep Sleep in World-Class Alpine Skiers: A Time-Efficient Alternative to Morning Supine Measurements.

Science.gov (United States)

Herzig, David; Testorelli, Moreno; Olstad, Daniela Schäfer; Erlacher, Daniel; Achermann, Peter; Eser, Prisca; Wilhelm, Matthias

2017-05-01

It is increasingly popular to use heart-rate variability (HRV) to tailor training for athletes. A time-efficient method is HRV assessment during deep sleep. To validate the selection of deep-sleep segments identified by RR intervals with simultaneous electroencephalography (EEG) recordings and to compare HRV parameters of these segments with those of standard morning supine measurements. In 11 world-class alpine skiers, RR intervals were monitored during 10 nights, and simultaneous EEGs were recorded during 2-4 nights. Deep sleep was determined from the HRV signal and verified by delta power from the EEG recordings. Four further segments were chosen for HRV determination, namely, a 4-h segment from midnight to 4 AM and three 5-min segments: 1 just before awakening, 1 after waking in supine position, and 1 in standing after orthostatic challenge. Training load was recorded every day. A total of 80 night and 68 morning measurements of 9 athletes were analyzed. Good correspondence between the phases selected by RR intervals vs those selected by EEG was found. Concerning root-mean-squared difference of successive RR intervals (RMSSD), a marker for parasympathetic activity, the best relationship with the morning supine measurement was found in deep sleep. HRV is a simple tool for approximating deep-sleep phases, and HRV measurement during deep sleep could provide a time-efficient alternative to HRV in supine position.

Postural ortostatisk takykardi-syndrom

DEFF Research Database (Denmark)

Brinth, Louise; Pors, Kirsten; Mehlsen, Jesper

2015-01-01

Postural orthostatic tachycardia syndrome (POTS) is a heterogeneous condition of dysautonomia and suspected autoimmunity characterized by abnormal increments in heart rate upon assumption of the upright posture accompanied by symptoms of cerebral hypoperfusion and sympathoexcitation. An increase...... in heart rate equal to or greater than 30 bpm or to levels higher than 120 bpm during a head-up tilt test is the main diagnostic criterion. Management includes both non-pharmacological and pharmacological treatment focusing on stress management, volume expansion and heart rate control....

Postural Control in Children: Implications for Pediatric Practice

Science.gov (United States)

Westcott, Sarah L.; Burtner, Patricia

2004-01-01

Based on a systems theory of motor control, reactive postural control (RPA) and anticipatory postural control (APA) in children are reviewed from several perspectives in order to develop an evidence-based intervention strategy for improving postural control in children with limitations in motor function. Research on development of postural…

Decrease in back strength in asymmetric trunk postures

NARCIS (Netherlands)

Vink, P.; Daanen, H. A M; Meijst, W. J.; Ligteringen, J.

1992-01-01

The extension force against resistance was recorded in 23 postures for 12 subjects to find explanations for the decrease in back strength in asymmetric postures. A reduction in muscle force in asymmetric postures was found up to 40%, but was strongly dependent on the plane in which asymmetry

Investigating the Effects of Different Working Postures on Cognitive Performance

Directory of Open Access Journals (Sweden)

Sharareh Mohammadi

2018-01-01

Conclusion This study demonstrates that cognitive performance is affected by working postures. This study demonstrates that standard sitting posture is the best posture. Therefore, it is recommended that sitting posture can help in increasing cognitive performance in the workplace.

Testing postural control among various osteoporotic patient groups: a literature review.

Science.gov (United States)

de Groot, Maartje H; van der Jagt-Willems, Hanna C; van Campen, Jos P C M; Lems, Willem F; Lamoth, Claudine J C

2012-10-01

Osteoporosis can cause vertebral fractures, which might lead to a flexed posture, impaired postural control and consequently increased fall risk. Therefore, the aim of the present review was to examine whether postural control of patients with osteoporosis, vertebral fractures, thoracic kyphosis and flexed posture is affected. Furthermore, instruments measuring postural control were evaluated and examined for sensitivity and easy clinical use. Until February 2011, electronic databases were systematically searched for cross-sectional studies. Methodological quality was assessed with a modified Downs & Black scale. Of the 518 found studies, 18 studies were included. Postural control was generally affected for patients with vertebral fractures, thoracic kyphosis and flexed posture. Patients with osteoporosis had impaired postural control when assessed with computerized instruments. Easy performance-based tests did not show any impairments. There is evidence for an impaired postural control in all patient groups included. Impaired postural control is an important risk factor for falls. Functional performance tests are not sensitive and specific enough to detect affected postural control in patients with osteoporosis. To detect impaired postural control among osteoporotic patients and to obtain more insight into the underlying mechanisms of postural control, computerized instruments are recommended, such as easy-to-use ambulant motion-sensing (accelerometry) technology. © 2012 Japan Geriatrics Society.

Coronary perfusion pressure and compression quality in maternal cardiopulmonary resuscitation in supine and left-lateral tilt positions: A prospective, crossover study using mannequins and swine models.

Science.gov (United States)

Dohi, Satoshi; Ichizuka, Kiyotake; Matsuoka, Ryu; Seo, Kohei; Nagatsuka, Masaaki; Sekizawa, Akihiko

2017-09-01

The risk of maternal and fetal mortality is high if cardiopulmonary arrest occurs during pregnancy. To assess the best position for maternal cardiopulmonary resuscitation (CPR), a prospective randomized crossover study was undertaken, involving basic life support mannequin-based simulation (BLS-MS) and a swine model of pulseless electrical activity (an unstable cardiac state) incorporating a fetal mannequin (PEA-FM). The BLS-MS (performed by certified rescuers) served to evaluate the quality of chest compressions in 30° left lateral tilt (LLT) and supine positions. Based on a 5-point scale, each rescuer subjectively graded their experience. The PEA-FM model was used to compare coronary perfusion pressure readings during CPR in supine, supine with left uterine displacement, 30° LLT, and 30° right lateral tilt positions. Compression rate and correctness of hand position, compression depth, and recoil were measures of compression quality (BLS-MS). Compared with LLT position, supine position enabled correct hand position (rate: 0.99 vs 0.88; p<0.05) and compression depth (rate: 0.76 vs 0.36; p<0.001) significantly more often. Moreover, BLS-MS rescuers found chest compressions significantly easier to perform with the mannequin in supine (vs LLT) position (difficulty score: 1.75 vs 3.95; p<0.001). In the PEA-FM study arm, supine position with left uterine displacement and right lateral tilt positions had the highest and lowest recorded coronary perfusion pressure readings, respectively. Supine position with left uterine displacement is optimal for maternal CPR. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Measurement of hemothorax amount in patients with non-penetrating chest trauma by supine chest AP radiograph

International Nuclear Information System (INIS)

Han, Heon; Yang, Joo Hyun; Na, Myung Hoon; Baik, Hee Jong

1994-01-01

To evaluate the predictability of amount of hemothorax in the patients with blunt chest trauma, supine chest AP radiographs of 66 patients were reviewed and statistically analyzed. In 66 patients, rib fractures were present in 53 patients, hemothorax in 46 patients, pneumothorax in 25 patients, and pulmonary contusions in 18 patients. Width and length of hemothorax were measured on supine chest AP radiograph, and were correlated with known drained amount of hemothorax. The presence and number of rib fracture, pulmonary contusion, subcutaneous emphysema, fracture of scapula and clavicle, and total opacification of hemithorax were also correlated with the drained amount of hemothorax. In multiple logistic regression analysis, width of hemothorax had the highest correlation with drained amount of hemothorax(regression coeffcient 0.718, p value 0.00005). The presence and number of rib fracture, scapular fracture, subcutaneous emphysema were also correlated with drained amount of hemothorax. But length of hemothorax, pulmonary contusion, clavicular fracture, total opacification of hemithorax were not correlated with drained amount of hemothorax. Measured width of hemothorax in supine chest AP radiograph is the most reliable predictor for estimation of the amount of hemothorax, and may also be used as an indication for the application of closed thoracostomy in the treatment of hemothorax

Measurement of hemothorax amount in patients with non-penetrating chest trauma by supine chest AP radiograph

Energy Technology Data Exchange (ETDEWEB)

Han, Heon; Yang, Joo Hyun; Na, Myung Hoon; Baik, Hee Jong [Chung-Ang Gil Hospital, Incheon (Korea, Republic of)

1994-10-15

To evaluate the predictability of amount of hemothorax in the patients with blunt chest trauma, supine chest AP radiographs of 66 patients were reviewed and statistically analyzed. In 66 patients, rib fractures were present in 53 patients, hemothorax in 46 patients, pneumothorax in 25 patients, and pulmonary contusions in 18 patients. Width and length of hemothorax were measured on supine chest AP radiograph, and were correlated with known drained amount of hemothorax. The presence and number of rib fracture, pulmonary contusion, subcutaneous emphysema, fracture of scapula and clavicle, and total opacification of hemithorax were also correlated with the drained amount of hemothorax. In multiple logistic regression analysis, width of hemothorax had the highest correlation with drained amount of hemothorax(regression coeffcient 0.718, p value 0.00005). The presence and number of rib fracture, scapular fracture, subcutaneous emphysema were also correlated with drained amount of hemothorax. But length of hemothorax, pulmonary contusion, clavicular fracture, total opacification of hemithorax were not correlated with drained amount of hemothorax. Measured width of hemothorax in supine chest AP radiograph is the most reliable predictor for estimation of the amount of hemothorax, and may also be used as an indication for the application of closed thoracostomy in the treatment of hemothorax.

Exaggerated supine oblique view of the cervical spine

International Nuclear Information System (INIS)

Abel, M.S.

1982-01-01

The technique of the 60 degree supine oblique view is described together with anatomic skeletal studies of this projection. The view is convenient for emergency room radiography and useful in other clinical radiography. The view separates widely the anterior and posterior portions of the vertebrae in a side to side projection. This makes for an elongated but detailed view of the articular processes, pedicles, and intervertebral foramina. In the cadavar specimen and clinically the view is shown to be useful in delineating fracture deformities of the articular process and visualizing constriction of the intervertebral foramen superiorly. Encroachment of the foramen superiorly is likely to compromise the emerging nerve root in this area

Bayesian non- and semi-parametric methods and applications

CERN Document Server

Rossi, Peter

2014-01-01

This book reviews and develops Bayesian non-parametric and semi-parametric methods for applications in microeconometrics and quantitative marketing. Most econometric models used in microeconomics and marketing applications involve arbitrary distributional assumptions. As more data becomes available, a natural desire to provide methods that relax these assumptions arises. Peter Rossi advocates a Bayesian approach in which specific distributional assumptions are replaced with more flexible distributions based on mixtures of normals. The Bayesian approach can use either a large but fixed number

Comparison of upright LBPP and supine LBNP in terms of cardiovascular and biomechanical parameters to simulate 1/6-G (lunar gravity) and 3/8-G (Martian gravity) activities

Science.gov (United States)

Schlabs, Thomas; Rosales-Velderrain, Armando; Ruckstuhl, Heidi; Richardson, Sara E.; Hargens, Alan

Background: Missions of astronauts to Moon and Mars may be planned in the future. From over 40 years of manned spaceflight it is known that the human body experiences cardiovascular and musculoskeletal losses and a decrease in aerobic fitness while exposed to reduced gravity. Because future missions will be much longer than before, further research is needed to improve Earth-based simulations of reduced gravity. Among others, two methods are capable of simu-lating fractional gravity on Earth: upright Lower Body Positive Pressure (LBPP) and supine Lower Body Negative Pressure (LBNP). No previous study has directly compared these two methods to determine which method is better suited to simulate both the biomechanical and cardiovascular responses of performing activity in lunar (1/6-G) and Martian (3/8-G) gravities. Taken previous studies into account and considering the fact that supine posture is closer to the established 10 head-up-tilt lunar simulation, we hypothesized that exercise performed in supine LBNP better simulates the cardiovascular conditions that occur in lunar and Martian gravities. Methods: 12 healthy normal subjects underwent a protocol consisting of resting and walking (0.25 Froude) with LBNP and LBPP. Each protocol was performed in simulated 1/6-G and 3/8-G. Heart-rate (HR), blood pressure, oxygen consumption (VO2), vertical component of the ground reaction force, comfort of the subject and perceived exertion of the subject (Borg Scale) were assessed. The obtained parameters were compared to predicted values for lunar and Martian gravity conditions in order to determine the method that shows the best level of agreement. Results: There was no difference in gait parameters between LBPP and LBNP simulation of lunar and Martian gravity (cadence: P=0.427, normalized stride length: P=0.373, duty fac-tor: P=0.302, and normalized vertical peak force (P=0.064). Mean blood pressure (P=0.398), comfort (P=0.832) and BORG rating (P=0.186) did not differ

Voluntarily controlled but not merely observed visual feedback affects postural sway

Science.gov (United States)

Asai, Tomohisa; Hiromitsu, Kentaro; Imamizu, Hiroshi

2018-01-01

Online stabilization of human standing posture utilizes multisensory afferences (e.g., vision). Whereas visual feedback of spontaneous postural sway can stabilize postural control especially when observers concentrate on their body and intend to minimize postural sway, the effect of intentional control of visual feedback on postural sway itself remains unclear. This study assessed quiet standing posture in healthy adults voluntarily controlling or merely observing visual feedback. The visual feedback (moving square) had either low or high gain and was either horizontally flipped or not. Participants in the voluntary-control group were instructed to minimize their postural sway while voluntarily controlling visual feedback, whereas those in the observation group were instructed to minimize their postural sway while merely observing visual feedback. As a result, magnified and flipped visual feedback increased postural sway only in the voluntary-control group. Furthermore, regardless of the instructions and feedback manipulations, the experienced sense of control over visual feedback positively correlated with the magnitude of postural sway. We suggest that voluntarily controlled, but not merely observed, visual feedback is incorporated into the feedback control system for posture and begins to affect postural sway. PMID:29682421

Development of low postural tone compensatory patterns in children - theoretical basis.

Science.gov (United States)

Gogola, Anna; Saulicz, Edward; Kuszewski, Michał; Matyja, Małgorzata; Myśliwiec, Andrzej

2014-01-01

Neurological literature indicates the existence of children with low postural tone without association with central nervous system damage. This fact induces to think about mechanisms, which allow these children to maintain upright posture. There is a suspicion that compensatory mechanism included in this process, enables to achieve upright posture, but at expense of body posture quality. Observations of children's developmental stages caused determination of some postural tone area, which comprise both children with normotonia and with low postural tone without characteristics of central nervous system (CNS) damage. Set of specific qualities allows determination of two types of low postural tone: spastoidal and atetoidal type. Spastoidal type is characterized by deep trunk muscles (local) low postural tone compensated by excessive tension of superficial muscles (global). Atetoidal type includes children with low postural tone in both deep and superficial muscles. At inefficient active subsystem, verticalization proceeds at excessive use of passive subsystem qualities, that is meniscus, ligament, bone shape, and muscles passive features. From neurodevelopmental point of view compensatory mechanisms can be used in children with low postural tone in order to achieve upright posture, but at expense of body posture quality.

Anatomy and histochemistry of spread-wing posture in birds. I. Wing drying posture in the double-crested cormorant, Phalacrocorax auritus.

Science.gov (United States)

Meyers, Ron A

1997-07-01

Spread-wing postures of birds often have been studied with respect to the function of behavior, but ignored with regard to the mechanism by which the birds accomplish posture. The double-crested cormorant, Phalacrocorax auritus, was used as a model for this study of spread-wing posture. Those muscles capable of positioning and maintaining the wing in extension and protraction were assayed histochemically for the presence of slow (postural) muscle fibers. Within the forelimb of Phalacrocorax, Mm. coracobrachialis cranialis, pectoralis thoracicus (cranial portion), deltoideus minor, triceps scapularis, and extensor metacarpi radialis pars dorsalis and ventralis were found to contain populations of slow-twitch or slow-tonic muscle fibers. These slow fibers in the above muscles are considered to function during spread-wing posture in this species. J Morphol 233:67-76, 1997. © 1997 Wiley-Liss, Inc. Copyright © 1997 Wiley-Liss, Inc.

Magnetism of a relaxed single atom vacancy in graphene

Science.gov (United States)

Wu, Yunyi; Hu, Yonghong; Xue, Li; Sun, Tieyu; Wang, Yu

2018-04-01

It has been suggested in literature that defects in graphene (e.g. absorbed atoms and vacancies) may induce magnetizations due to unpaired electrons. The nature of magnetism, i.e. ferromagnetic or anti-ferromagnetic, is dependent on a number of structural factors including locations of magnetic moments and lattice symmetry. In the present work we investigated the influence of a relaxed single atom vacancy in garphnene on magnetization which were obtained under different pinning boundary conditions, aiming to achieve a better understanding of the magnetic behaviors of graphene. Through first principles calculations, we found that major spin polarizations occur on atoms that deviate slightly from their original lattice positions, and pinning boundaries could also affect the relaxed positions of atoms and determine which atom(s) would become the main source(s) of total spin polarizations and magnetic moments. When the pinning boundary condition is free, a special non-magnetic and semi-conductive structure may be obtained, suggesting that magnetization should more readily occur under pinning boundary conditions.

The technique of craniospinal irradiation of paediatric patients in supine position

International Nuclear Information System (INIS)

Slampa, P.; Seneklova, Z.; Simicek, J.; Soumarova, R.; Burkon, P.; Burianova, L.

2001-01-01

Background. Postoperative radiation therapy has significant impact on local control and overall survival of paediatric patients with brain tumours but an irradiated volume is often a controversial issue. Our aim was to describe a new technique of craniospinal irradiation as a postoperative treatment in patients with the risk of relapse of brain tumours as well as to estimate the side effects of such craniospinal irradiation. Patients and methods. In the last 4 years, 17 paediatric patients under 15 years of age with medulloblastoma (8) ependymoma (6) and glioblastoma (3) received postoperative craniospinal axis radiotherapy by a new technique developed in our departments. This technique is based on irradiation in supine position with the use of asymmetric jaws of the linear accelerator. Results. Radiotherapy was well tolerated and dose-reduction was not needed in any case. Skin reactions were mild in all patients. The gastrointestinal and haematological toxicity was mild to moderate (WHO grade I-II). Conclusion. The proposed new technique of craniospinal irradiation is advantageous in terms of side effects and could be recommended to be widely used. Craniospinal irradiation in supine position is an alternative method to the treatment in prone position. The evaluation of the effectiveness was limited by a short follow-up interval. (author)

Posture Detection Based on Smart Cushion for Wheelchair Users

Directory of Open Access Journals (Sweden)

Congcong Ma

2017-03-01

Full Text Available The postures of wheelchair users can reveal their sitting habit, mood, and even predict health risks such as pressure ulcers or lower back pain. Mining the hidden information of the postures can reveal their wellness and general health conditions. In this paper, a cushion-based posture recognition system is used to process pressure sensor signals for the detection of user’s posture in the wheelchair. The proposed posture detection method is composed of three main steps: data level classification for posture detection, backward selection of sensor configuration, and recognition results compared with previous literature. Five supervised classification techniques—Decision Tree (J48, Support Vector Machines (SVM, Multilayer Perceptron (MLP, Naive Bayes, and k-Nearest Neighbor (k-NN—are compared in terms of classification accuracy, precision, recall, and F-measure. Results indicate that the J48 classifier provides the highest accuracy compared to other techniques. The backward selection method was used to determine the best sensor deployment configuration of the wheelchair. Several kinds of pressure sensor deployments are compared and our new method of deployment is shown to better detect postures of the wheelchair users. Performance analysis also took into account the Body Mass Index (BMI, useful for evaluating the robustness of the method across individual physical differences. Results show that our proposed sensor deployment is effective, achieving 99.47% posture recognition accuracy. Our proposed method is very competitive for posture recognition and robust in comparison with other former research. Accurate posture detection represents a fundamental basic block to develop several applications, including fatigue estimation and activity level assessment.

Relationship between Postural Deformities and Frontal Function in Parkinson's Disease

OpenAIRE

Ninomiya, Satoko; Morita, Akihiko; Teramoto, Hiroko; Akimoto, Takayoshi; Shiota, Hiroshi; Kamei, Satoshi

2015-01-01

Postural deformities and executive dysfunction (ED) are common symptoms of Parkinson's disease (PD); however, the relationship between postural deformities and ED in patients with PD remains unclear. This study assessed the relationship between postural deformities and ED in patients with PD. Sixty-five patients with sporadic PD were assessed for the severity of postural deformities and executive function. The severity of postural deformities was scored using the United Parkinson's Disease Ra...

PENINGKATAN STABILITAS POSTURAL PADA LANSIA MELALUI BALANCE EXERCISE

Directory of Open Access Journals (Sweden)

Kusnanto .

2010-12-01

Full Text Available Stabilitas postural adalah masalah yang umum pada lansia. Balance exercise dapat dijadikan alternative latihan bagi lansia. Latihan ini meliputi 5 gerakan (plantar flexion, hip flexion, hip flexion, knee flexion dan side leg raise. Penelitian ini bertujuan untuk menganalisa efek dari balance exercise terhadap peningkatan stabilitas postural pada lansia. Penelitian ini menggunakan design pre eksperimen. Populasi yang digunakan adalah lansia di Panti Wreda Bangkalan. Total sampel adalah 11 responden, yang diambil berdasarkan kriteria inklusi. Variabel dependen adalah balance exercise dan variabel independen adalah stabilitas postural. Stabilitas postural diukur menggunakan 2 tes, yaitu tes Tinetti dan TUGT (Time Up and Go Test. Data dianalisa menggunakan paired t test dengan level signifikan 0,05. Hasil penelitian menunjukkan bahwa balance exercise secara signifikan dapat meningkatkan stabilitas postural. Pada tes Tinetti (p=0,000 dan di TUGT (p=0,001. Sehingga dapat disimpulkan bahwa terdapat hasil yang signifikan antara balance exercise dengan peningkatan stabilitas postural pada lansia. Hal ini disebabkan Karena balance exercise dapat membuat otot lansia menjadi hipertrofi. Hipertrofi dapat meningkatkan kekuatan otot sehingga stabilitas postural lansia dapat meningkat. Penelitian yang akan datang diharapkan melibatkan lebih banyak responden dengan waktu penelitian yang lebih lama dan pengukuran yang lebih baik untuk memastikan hasil yang lebih akurat.

Clinical evaluation of postural posture of patients with previous stroke subjected to early rehabilitation

Directory of Open Access Journals (Sweden)

Anna Sagan

2018-02-01

Full Text Available Introduction: Impairment disorders are often found in patients with stroke and impairment of motor and cognitive functions. This is a very serious complication because, by imposing a motor impairment, it aggravates the condition of disability and makes it difficult to conduct physical rehabilitation.The resulting neurological deficits due to stroke determine functional disorders. The possibility of locomotion is usually compromised, therefore the risk of falls increases significantly. The aim of the work is to present Postural Assesment Scale for Strock PASS with the postural stroke assessment scale, the impact of early rehabilitation of patients staying in the neurology ward.Material and methods: Postural examination was carried out among 17 people, of which 8 were women, and 9 were male. The study was divided into two stages. The first stage occurred immediately after the stroke and the second one before the patient was discharged from the ward. Research was carried out at the Biegański Specialist Hospital in Grudziądz in the Department of Neurology and Clinical Neuroimmunology and Impact Department.Conclusions: The results of the postural studies carried out in people with previous stroke subjected to early physiotherapy have a beneficial effect of the conducted therapy. There are positive changes between the first and the final examination of the patients.

Postural balance in low back pain patients

DEFF Research Database (Denmark)

Maribo, Thomas; Schiøttz-Christensen, Berit; Jensen, Lone Donbæk

2012-01-01

INTRODUCTION: Altered postural control has been observed in low back pain (LBP) patients. They seem to be more dependent on vision when standing. The objective of the study was to determine concurrent and predictive validity of measures of postural stability in LBP patients. MATERIALS AND METHODS......: Centre of Pressure (CoP) measurements were tested against pain, fear of pain, and physical function. Velocity, anterior-posterior displacement, and the Romberg Ratio obtained on a portable force platform were used as measures of postural stability. RESULTS: Baseline and 12-week follow-up results of 97....... CONCLUSION: This first study of concurrent and predictive validity of postural balance in LBP patients revealed no association between CoP measures and pain, fear of pain, and physical function....

Studies on asymptomatic cerebral ischemia in coronary heart disease with special reference to evaluation of postural changes in cerebral blood flow with {sup 99m}Tc-ECD brain SPECT

Energy Technology Data Exchange (ETDEWEB)

Sinozaki, Hideko [Teikyo Univ., Tokyo (Japan). Faculty of Medicine

2001-03-01

Postural changes in cerebral blood flow in patients with coronary heart disease (CHD) were evaluated with SPECT to detect asymptomaic cerebral ischemia (ACI). {sup 99m}Tc-ECD was used as a tracer. We developed a new analysis system for the processing of multiple images, making it possible to avoid the spatial shift in ROIs in different positions. The severity of ACI was classified into 3 groups based on SPECT findings in the supine position: group 1 without any abnormalities in cerebral perfusion, group 2 with a single perfusion defect, and group 3 with a number of perfusion defects. No cerebral siteobserved in any group showed a significant difference between the supine and upright positions in cerebral perfusion. Each group in each position, however, revealed a consistent perfusion pattern characterized by a significant decrease in perfusion in the occipital, temporal and frontal lobes. Moreover, the decrease in the latter two sites was significantly greater than in the former site. Concerning clinical profiles, hypertension and the thickness of the intima and media complex (TIMC) of the common carotid artery significantly correlated with the severity of ACI. Furthermore, in multiple regression analysis, only TIMC was identified as a significant determinant of ACI. In conclusion, cerebral blood flow determined with {sup 99m}Tc-ECD SPECT could accurately detect ACI in patients with CHD. (author)

Relationship between Postural Deformities and Frontal Function in Parkinson’s Disease

Directory of Open Access Journals (Sweden)

Satoko Ninomiya

2015-01-01

Full Text Available Postural deformities and executive dysfunction (ED are common symptoms of Parkinson’s disease (PD; however, the relationship between postural deformities and ED in patients with PD remains unclear. This study assessed the relationship between postural deformities and ED in patients with PD. Sixty-five patients with sporadic PD were assessed for the severity of postural deformities and executive function. The severity of postural deformities was scored using the United Parkinson’s Disease Rating Scale item 28 score: no postural deformity (0, mild postural deformities (1, or severe postural deformities (2–4. Executive function was assessed using the Behavioral Assessment of the Dysexecutive Syndrome (BADS and an age-controlled standardized BADS score <70 was defined as ED. Age-controlled standardized BADS scores were compared across the three groups using the Kruskal-Wallis test. Relationship between ED and the severity of postural deformities was assessed using the Mann-Whitney U test. Age-controlled standardized BADS score significantly differed among the three groups P=0.005. ED was significantly related to the severity of postural deformities P=0.0005. The severity of postural deformities was associated with a lower age-controlled standardized BADS score and ED, and these findings suggest that postural deformities were associated with frontal dysfunction in patients with PD.

Inactivity periods and postural change speed can explain atypical postural change patterns of Caenorhabditis elegans mutants.

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Fukunaga, Tsukasa; Iwasaki, Wataru

2017-01-19

With rapid advances in genome sequencing and editing technologies, systematic and quantitative analysis of animal behavior is expected to be another key to facilitating data-driven behavioral genetics. The nematode Caenorhabditis elegans is a model organism in this field. Several video-tracking systems are available for automatically recording behavioral data for the nematode, but computational methods for analyzing these data are still under development. In this study, we applied the Gaussian mixture model-based binning method to time-series postural data for 322 C. elegans strains. We revealed that the occurrence patterns of the postural states and the transition patterns among these states have a relationship as expected, and such a relationship must be taken into account to identify strains with atypical behaviors that are different from those of wild type. Based on this observation, we identified several strains that exhibit atypical transition patterns that cannot be fully explained by their occurrence patterns of postural states. Surprisingly, we found that two simple factors-overall acceleration of postural movement and elimination of inactivity periods-explained the behavioral characteristics of strains with very atypical transition patterns; therefore, computational analysis of animal behavior must be accompanied by evaluation of the effects of these simple factors. Finally, we found that the npr-1 and npr-3 mutants have similar behavioral patterns that were not predictable by sequence homology, proving that our data-driven approach can reveal the functions of genes that have not yet been characterized. We propose that elimination of inactivity periods and overall acceleration of postural change speed can explain behavioral phenotypes of strains with very atypical postural transition patterns. Our methods and results constitute guidelines for effectively finding strains that show "truly" interesting behaviors and systematically uncovering novel gene

A Comparison of the Physiology and Mechanics of Exercise in LBNP and Upright Gait

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Boda, W. L.; Watenpaugh, D. E.; Ballard, R. E.; Chang, D.; Looft-Wilson, R.; Hargens, A. R.

1996-01-01

Bone, muscular strength, aerobic capacity, and normal fluid pressure gradients within the body are lost during bed rest and spaceflight. Lower Body Negative Pressure (LBNP) exercise may create musculoskeletal and cardiovascular strains equal to a greater than those experienced on Earth and elucidate some of the mechanisms for maintaining bone integrity. LBNP exercise simulates gravity during supine posture by using negative pressure to pull subjects inward against a treadmill generating footward forces and increasing transmural pressures. Footward forces are generated which equal the product of the pressure differential and the cross-sectional area of the LBNP waist seal. Subjects lie supine within the chamber with their legs suspended from one another via cuffs, bungee cords, and pulleys, such that each leg acts as a counterweight to the other leg during the gait cycle. The subjects then walk or run on a treadmill which is positioned vertically within the chamber. Supine orientation allows only footward force production due to the negative pressure within the chamber. The purpose of this study was to determine if the kinematics, kinetics, and metabolic rate during supine walking and slow running on a vertical treadmill within LBNP are similar to those on a treadmill in 1-g environment in an upright posture.

Compromising Postural Balance in the Elderly

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Swanenburg, Jaap; de Bruin, Eling D.; Uebelhart, Daniel; Mulder, Theo

2009-01-01

Background: Additional tasks that are assumed to disturb standing postural control can be divided in added motor or added cognitive tasks. It is unknown which type of task causes the most disturbances of postural control in elderly. Objective: The aim of this study was to determine whether the dual

Postural steadiness and ankle force variability in peripheral neuropathy

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Paxton, Roger J.; Feldman-Kothe, Caitlin; Trabert, Megan K.; Hitchcock, Leah N.; Reiser, Raoul F.; Tracy, Brian L.

2015-01-01

Introduction The purpose was to determine the effect of peripheral neuropathy (PN) on motor output variability for ankle muscles of older adults, and the relation between ankle motor variability and postural stability in PN patients. Methods Older adults with (O-PN) and without PN (O), and young adults (Y) underwent assessment of standing postural stability and ankle muscle force steadiness. Results O-PN displayed impaired ankle muscle force control and postural stability compared with O and Y groups. For O-PN, the amplitude of plantarflexor force fluctuations was moderately correlated with postural stability under no-vision conditions (r = 0.54, P = 0.01). Discussion The correlation of variations in ankle force with postural stability in PN suggests a contribution of ankle muscle dyscontrol to the postural instability that impacts physical function for older adults with PN. PMID:26284897

Three-dimensional intrafractional movement of prostate measured during real-time tumor-tracking radiotherapy in supine and prone treatment positions

International Nuclear Information System (INIS)

Kitamura, Kei; Shirato, Hiroki; Seppenwoolde, Yvette; Onimaru, Rikiya; Oda, Makoto; Fujita, Katsuhisa; Shimizu, Shinichi; Shinohara, Nobuo; Harabayashi, Toru; Miyasaka, Kazuo

2002-01-01

Purpose: To quantify three-dimensional (3D) movement of the prostate gland with the patient in the supine and prone positions and to analyze the movement frequency for each treatment position. Methods and Materials: The real-time tumor-tracking radiotherapy (RTRT) system was developed to identify the 3D position of a 2-mm gold marker implanted in the prostate 30 times/s using two sets of fluoroscopic images. The linear accelerator was triggered to irradiate the tumor only when the gold marker was located within the region of the planned coordinates relative to the isocenter. Ten patients with prostate cancer treated with RTRT were the subjects of this study. The coordinates of the gold marker were recorded every 0.033 s during RTRT in the supine treatment position for 2 min. The patient was then moved to the prone position, and the marker was tracked for 2 min to acquire data regarding movement in this position. Measurements were taken 5 times for each patient (once a week); a total of 50 sets for the 10 patients was analyzed. The raw data from the RTRT system were filtered to reduce system noise, and the amplitude of movement was then calculated. The discrete Fourier transform of the unfiltered data was performed for the frequency analysis of prostate movement. Results: No apparent difference in movement was found among individuals. The amplitude of 3D movement was 0.1-2.7 mm in the supine and 0.4-24 mm in the prone positions. The amplitude in the supine position was statistically smaller in all directions than that in the prone position (p < 0.0001). The amplitude in the craniocaudal and AP directions was larger than in the left-right direction in the prone position (p < 0.0001). No characteristic movement frequency was detected in the supine position. The respiratory frequency was detected for all patients regarding movement in the craniocaudal and AP directions in the prone position. The results of the frequency analysis suggest that prostate movement is

Posture and Texting: Effect on Balance in Young Adults.

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Nurul Retno Nurwulan

Full Text Available Using a mobile phone while doing another activity is a common dual-task activity in our daily lives. This study examined the effect of texting on the postural stability of young adults. Twenty college students were asked to perform static and dynamic postural stability tasks. Traditional COP and multivariate multiscale entropy (MMSE were used to assess the static postural stability and the Star Excursion Balance Test (SEBT was used to assess the dynamic postural stability. Results showed that (1 texting impaired postural stability, (2 the complexity index did not change much although the task conditions changed, and (3 performing texting is perceived to be more difficult.

Postural Response Signal Characteristics Identified by Method of Developed Statokinesigram

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Barbolyas Boris

2015-12-01

Full Text Available Human postural system is taken as complex biological system with specific input and output time characteristics, in this study. Evaluation of measured output characteristics is useful in medical diagnostics or in describing postural system disorders. System theory principle provide suitable basis for postural signals analysis. Participating volunteers were instructed to maintain quiet upright stance posture on firm support surface of stabilometric platform for 60s. Postural system actuation was realized by vibration stimuli applied bilaterally on Achilles tendons for 20s. Postural reaction signal, its time profile and static and dynamic characteristics were evaluated by Method of Developed Statokinesigram Trajectory (MDST.

Head movements and postures as pain behavior

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Al-Hamadi, Ayoub; Limbrecht-Ecklundt, Kerstin; Walter, Steffen; Traue, Harald C.

2018-01-01

Pain assessment can benefit from observation of pain behaviors, such as guarding or facial expression, and observational pain scales are widely used in clinical practice with nonverbal patients. However, little is known about head movements and postures in the context of pain. In this regard, we analyze videos of three publically available datasets. The BioVid dataset was recorded with healthy participants subjected to painful heat stimuli. In the BP4D dataset, healthy participants performed a cold-pressor test and several other tasks (meant to elicit emotion). The UNBC dataset videos show shoulder pain patients during range-of-motion tests to their affected and unaffected limbs. In all videos, participants were sitting in an upright position. We studied head movements and postures that occurred during the painful and control trials by measuring head orientation from video over time, followed by analyzing posture and movement summary statistics and occurrence frequencies of typical postures and movements. We found significant differences between pain and control trials with analyses of variance and binomial tests. In BioVid and BP4D, pain was accompanied by head movements and postures that tend to be oriented downwards or towards the pain site. We also found differences in movement range and speed in all three datasets. The results suggest that head movements and postures should be considered for pain assessment and research. As additional pain indicators, they possibly might improve pain management whenever behavior is assessed, especially in nonverbal individuals such as infants or patients with dementia. However, in advance more research is needed to identify specific head movements and postures in pain patients. PMID:29444153

Effects of disease severity and medication state on postural control asymmetry during challenging postural tasks in individuals with Parkinson's disease.

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Barbieri, Fabio A; Polastri, Paula F; Baptista, André M; Lirani-Silva, Ellen; Simieli, Lucas; Orcioli-Silva, Diego; Beretta, Victor S; Gobbi, Lilian T B

2016-04-01

The aim of this study was to investigate the effects of disease severity and medication state on postural control asymmetry during challenging tasks in individuals with Parkinson's disease (PD). Nineteen people with PD and 11 neurologically healthy individuals performed three standing task conditions: bipedal standing, tandem and unipedal adapted standing; the individuals with PD performed the tasks in ON and OFF medication state. The participants with PD were distributed into 2 groups according to disease severity: unilateral group (n=8) and bilateral group (n=11). The two PD groups performed the evaluations both under and without the medication. Two force plates were used to analyze the posture. The symmetric index was calculated for various of center of pressure. ANOVA one-way (groups) and two-way (PD groups×medication), with repeated measures for medication, were calculated. For main effects of group, the bilateral group was more asymmetric than CG. For main effects of medication, only unipedal adapted standing presented effects of PD medication. There was PD groups×medication interaction. Under the effects of medication, the unilateral group presented lower asymmetry of RMS in anterior-posterior direction and area than the bilateral group in unipedal adapted standing. In addition, the unilateral group presented lower asymmetry of mean velocity, RMS in anterior-posterior direction and area in unipedal standing and area in tandem adapted standing after a medication dose. Postural control asymmetry during challenging postural tasks was dependent on disease severity and medication state in people with PD. The bilateral group presented higher postural control asymmetry than the control and unilateral groups in challenging postural tasks. Finally, the medication dose was able to reduce postural control asymmetry in the unilateral group during challenging postural tasks. Copyright © 2015 Elsevier B.V. All rights reserved.

Does the Supine Position Affect the Nasal Profile in Rhinoplasty Patients? A Comparison of Nasal Anthropometric Measurements in Different Body Positions.

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Kim, Su Jin; Ryu, In Yong; Kim, Sung Wan; Lee, Kun Hee

2017-10-16

Rhinoplasty surgeons are aware that the nasal profile differs according to body position, namely, the erect position in the consultation room vs the supine position on the operating table. It is not clear whether this difference is caused by an optical illusion or skin laxity due to positional change. To evaluate anthropometric measurements of the nose with different body positions and determine whether the supine position affects the nasal profile. In this retrospective study, 103 patients who underwent primary rhinoplasty were enrolled. Preoperatively, all patients underwent lateral cephalography in the erect position, and facial computed tomography (CT), in the supine position. We measured four nasal anthropometric parameters (the nasofrontal, nasolabial, and nasomental angles, and Simon's ratio) on lateral cephalograms and facial CT images, and compared these parameters between the two body positions. The nasofrontal angle was greater on facial CT than on cephalograms (P sex, or body mass index (P > 0.05 each). We found no significant difference (P > 0.05) between the two positions in the nasolabial angle, nasomental angle, or Simon's ratio. The supine position does affect the nasal profile, especially in the radix area. Surgeons need to consider this difference in patients undergoing rhinoplasty. 2. © 2017 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com

A Dosimetric Comparison of Accelerated Partial Breast Irradiation Techniques: Multicatheter Interstitial Brachytherapy, Three-Dimensional Conformal Radiotherapy, and Supine Versus Prone Helical Tomotherapy

International Nuclear Information System (INIS)

Patel, Rakesh R.; Becker, Stewart J.; Das, Rupak K.; Mackie, Thomas R.

2007-01-01

Purpose: To compare dosimetrically four different techniques of accelerated partial breast irradiation (APBI) in the same patient. Methods and Materials: Thirteen post-lumpectomy interstitial brachytherapy (IB) patients underwent imaging with preimplant computed tomography (CT) in the prone and supine position. These CT scans were then used to generate three-dimensional conformal radiotherapy (3D-CRT) and prone and supine helical tomotherapy (PT and ST, respectively) APBI plans and compared with the treated IB plans. Dose-volume histogram analysis and the mean dose (NTD mean ) values were compared. Results: Planning target volume coverage was excellent for all methods. Statistical significance was considered to be a p value mean dose of 1.3 Gy 3 and 1.2 Gy 3 , respectively. Both of these methods were statistically significantly lower than the supine external beam techniques. Overall, all four methods yielded similar low doses to the heart. Conclusions: The use of IB and PT resulted in greater normal tissue sparing (especially ipsilateral breast and lung) than the use of supine external beam techniques of 3D-CRT or ST. However, the choice of APBI technique must be tailored to the patient's anatomy, lumpectomy cavity location, and overall treatment goals

An investigation into essential aspects of posture in primary school ...

African Journals Online (AJOL)

Postures of the subjects were analysed by means of photographic images using the pro forma of Barlow (1956, 1990). The majority of the executives had malposture with 2.3%, 23.3%, 58.1% and 16.3% and 6.3% of the subjects being categorised with slight postural defects, severe postural defects, very severe postural ...

Association between temporomandibular disorders and abnormal head postures

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Evandro Francisco FAULIN

2015-01-01

Full Text Available This study examines the possible correlation between the prevalence of temporomandibular disorders (TMD and different head postures in the frontal and sagittal planes using photographs of undergraduate students in the School of Dentistry at the Universidade de Brasília - UnB, Brazil. In this nonrandomized, cross-sectional study, the diagnoses of TMD were made with the Research Diagnostic Criteria (RDC/TMD axis I. The craniovertebral angle was used to evaluate forward head posture in the sagittal plane, and the interpupillary line was used to measure head tilt in the frontal plane. The measurements to evaluate head posture were made using the Software for the Assessment of Posture (SAPO. Students were divided into two study groups, based on the presence or absence of TMD. The study group comprised 46 students and the control group comprised 80 students. Data about head posture and TMD were analyzed with the Statistical Package for the Social Sciences, version 13. Most cases of TMD were classified as degenerative processes (group III, followed by disk displacement (group II and muscle disorders (group I. There was no sex predominance for the type of disorder. No association was found between prevalence rates for head postures in the frontal plane and the occurrence of TMD. The same result was found for the association of TMD diagnosis with craniovertebral angle among men and women, and the group that contained both men and women. Abnormal head postures were common among individuals both with and without TMD. No association was found between head posture evaluated in the frontal and sagittal planes and TMD diagnosis with the use of RDC/TMD.

Characterization of postural control impairment in women with fibromyalgia

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Sempere-Rubio, Núria; López-Pascual, Juan; Aguilar-Rodríguez, Marta; Cortés-Amador, Sara; Espí-López, Gemma; Villarrasa-Sapiña, Israel

2018-01-01

The main goal of this cross-sectional study was to detect whether women with fibromyalgia syndrome (FMS) have altered postural control and to study the sensory contribution to postural control. We also explored the possibility that self-induced anxiety and lower limb strength may be related to postural control. For this purpose, 129 women within an age range of 40 to 70 years were enrolled. Eighty of the enrolled women had FMS. Postural control variables, such as Ellipse, Root mean square (RMS) and Sample entropy (SampEn), in both directions (i.e. mediolateral and anteroposterior), were calculated under five different conditions. A force plate was used to register the center of pressure shifts. Furthermore, isometric lower limb strength was recorded with a portable dynamometer and normalized by lean body mass. The results showed that women with FMS have impaired postural control compared with healthy people, as they presented a significant increase in Ellipse and RMS values (pPostural control also worsens with the gradual alteration of sensory inputs in this population (p0.05). There were no significant correlations between postural control and lower limb strength (p>0.05). Therefore, women with FMS have impaired postural control that is worse when sensory inputs are altered but is not correlated with their lower limb strength. PMID:29723223

Effect of magnification loupes on dental hygiene student posture.

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Maillet, J Peggy; Millar, A Michele; Burke, Jillian M; Maillet, Michelle A; Maillet, Wayne A; Neish, Nancy R

2008-01-01

The chair-side work posture of dental hygienists has long been a concern because of health-related problems potentially caused or exacerbated by poor posture. The purpose of this study was to investigate if using magnification loupes improved dental hygiene students' posture during provision of treatment. The treatment chosen was hand-scaling, and the effect of the timing of introduction of the loupes to students was also examined. Thirty-five novice dental hygiene students took part in the study. Each student was assessed providing dental hygiene care with and without loupes, thus controlling for innate differences in natural posture. Students were randomized into two groups. Group one used loupes in the first session and did not use them for the second session. Group two reversed this sequence. At the end of each session, all students were videotaped while performing scaling procedures. Their posture was assessed using an adapted version of Branson et al.'s Posture Assessment Instrument (PAI). Four raters assessed students at three time periods for nine posture components on the PAI. A paired t-test compared scores with and without loupes for each student. Scores showed a significant improvement in posture when using loupes (ppostural benefit is realized by requiring students to master the use of magnification loupes as early as possible within the curriculum.

Vertebral Fracture Assessment in Supine Position : Comparison by Using Conventional Semiquantitative Radiography and Visual Radiography

NARCIS (Netherlands)

Hospers, Ilone C.; van der Laan, Johan G.; Zeebregts, Clark J.; Nieboer, Patrick; Wolffenbuttel, Bruce H. R.; Dierckx, Rudi A.; Kreeftenberg, Herman G.; Jager, Pieter L.; Slart, Riemer H. J. A.

Purpose: To retrospectively evaluate the accuracy of vertebral fracture assessment (VFA) performed with the patient in the supine position and conventional semiquantitative radiography of the spine by using conventional visual radiography of the spine as the reference standard. Materials and

The influence of recovery posture on post-exercise hypotension in normotensive men.

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Raine, N M; Cable, N T; George, K P; Campbell, I G

2001-03-01

Postexercise hypotension may be the result of an impaired vasoconstrictor response. This hypothesis was investigated by examining the central and peripheral hemodynamic responses during supine and seated recovery after maximal upright exercise. After supine or seated baseline measurements, seven normotensive male volunteers completed a graded upright cycling protocol to volitional exhaustion. This was immediately followed by either supine or seated recovery. Measurements of pulsatile arterial blood pressure and central and peripheral hemodynamic variables recorded 30 min before exercise were compared with those taken throughout 60 min of recovery. Compared with baseline, mean arterial pressure (MAP) was reduced after exercise (P different between the supine (-9 +/- 4 mm Hg) and seated positions (-6 +/- 2 mm Hg). This change in MAP was associated with a reduction in diastolic blood pressure (DBP) (P pressure (APP) (P positions, respectively. The reduction in APP during seated recovery was accompanied by a decline in stroke volume (SV) (P position, that limited the contribution of cardiac output (CO) to the maintenance of MAP. This effect of seated recovery was compensated by greater systemic (SVR) and regional vascular resistances in the forearm (FVR) and the forearm skin (SkVRA). There was also evidence of an augmented return of FVR and SkVRA to resting levels in the seated position after exercise. The lower peripheral resistance in the supine compared with seated recovery position suggests there is potential for greater vasoconstriction, although this is not evoked to increase blood pressure. This further suggests that the arterial baroreceptor reflex is reset to a lower operating pressure after exercise.

Influence of pain on postural control in women with neck pain

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Juliana Soares

2013-04-01

Full Text Available The objective of this study was to investigate the influence of pain on postural control in women with neck pain and the relationship with possible changes in sensory systems and posture. The neck pain group was composed of women, aged between 20 and 50years, complaining of neck pain for more than three months; the control group was composed of women without complaints of neck pain. For the characterization of the groups, we used anamnesis, neck disability index and Visual Analogue Scale. Postural balance was assessed on force platform. Postural balance with manipulation of the sensory systems was measured by Foam Laser Dynamic Posturography, exposing the individual to six sensory organization tests. Posture was assessed by the Postural Assessment Software. The normality of the variables were verified using Shapiro-Wilk test, Student’s t-test and Mann-Whitney test for comparison between groups, with a significance level of5%. Groups were homogeneous in demographic variables. We observed higher amplitude and displacement velocity of the center of pressure in the neck pain group, showing greater postural balance. There were significant diferences incraniovertebral angle, showing forward head posture in symptomatic women. In dynamics posturography, we observed a difference between the groups: the score obtainedin the six sensory conditions showed that neck pain group presented greater balance impairment. Neck pain and forward head posture have a deleterious effect on postural control in symptomatic women, both in the static posture and dynamic posture.

Postural Variables in Girls Practicing Volleyball

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Grabara, Malgorzata; Hadzik, Andrzej

2009-01-01

Study aim: To assess body posture of young female volleyball players in relation to their untrained mates. Material and methods: A group of 42 volleyball players and another of 43 untrained girls, all aged 13-16 years were studied with respect to their body posture indices by using computer posturography. Spinal angles and curvatures were…

Nuclear spin-lattice relaxation in n -type insulating and metallic GaAs single crystals

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Lu, J.; Hoch, M. J. R.; Kuhns, P. L.; Moulton, W. G.; Gan, Z.; Reyes, A. P.

2006-09-01

The coupling of electron and nuclear spins in n-GaAs changes significantly as the donor concentration n increases through the insulator-metal critical concentration nC˜1.2×1016cm-3 . The present measurements of the Ga71 relaxation rates W made as a function of magnetic field (1-13T) and temperature (1.5-300K) for semi-insulating GaAs and for three doped n-GaAs samples with donor concentrations n=5.9×1015 , 7×1016 , and 2×1018cm-3 , show marked changes in the relaxation behavior with n . Korringa-like relaxation is found in both metallic samples for T30K phonon-induced nuclear quadrupolar relaxation is dominant. The relaxation rate measurements permit determination of the electron probability density at Ga71 sites. A small Knight shift of -3.3ppm was measured on the most metallic (2×1018cm-3) sample using magic-angle spinning at room temperature. For the n=5.9×1015cm-3 sample, a nuclear relaxation model involving the Fermi contact hyperfine interaction, rapid spin diffusion, and exchange coupled local moments is proposed. While the relaxation rate behavior with temperature for the weakly metallic sample, n=7×1016cm-3 , is similar to that found for the just-insulating sample, the magnetic field dependence is quite different. For the 5.9×1015cm-3 sample, increasing the magnetic field leads to a decrease in the relaxation rate, while for the 7×1016cm-3 sample this results in an increase in the relaxation rate ascribed to an increase in the density of states at the Fermi level as the Landau level degeneracy is increased.

Postural changes in dental hygienists. Four-year longitudinal study.

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Barry, R M; Woodall, W R; Mahan, J M

1992-01-01

Numerous surveys identify the occurrence of musculoskeletal complaints as a concern in dentistry. However, no longitudinal data exist to indicate whether postural changes occur as a result of practicing dental hygiene. The purpose of this preliminary, four-year longitudinal study was to investigate whether any postural changes developed during the hygienists' clinical education and/or during subsequent dental hygiene practice after one and/or two years. It was anticipated that the awkward positions and intense physical demands placed on hygienists might initiate musculoskeletal problems, but that no postural changes would occur over this short period of time. Nine of 10 dental hygienists in the graduating class of 1987 were surveyed for existing musculoskeletal complaints, and the subjects were photographed for a measurement of postural change. Responses from participants indicated an increase in musculoskeletal-related complaints in each of the six areas investigated. The photographic findings indicated that one of the nine hygienists showed an increase in forward head posture, a postural change.

Effect of yoga relaxation techniques on performance of digit-letter substitution task by teenagers

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Pradhan Balaram

2009-01-01

Full Text Available Background/Aims : Memory and selective attention are important skills for academic and professional performance. Techniques to improve these skills are not taught either in education or company training courses. Any system which can systematically improve these skills will be of value in schools, universities, and workplaces. Aims:To investigate possible improvements in memory and selective attention, as measured by the Digit-Letter Substitution Task (DLST, due to practice of Cyclic Meditation (CM, a yoga relaxation technique, as compared to Supine Rest (SR. Materials and Methods : Subjects consisted of 253 school students, 156 boys, 97 girls, in the age range 13-16 years, who were attending a 10-day yoga training course during summer vacation. The selected subjects had English as their medium of instruction in school and they acted as their own controls. They were allocated to two groups, and tested on the DLST, immediately before and after 22.5 minutes practice of CM on one day, and immediately before and after an equal period of SR on the other day. The first group performed CM on day 9 and SR on day 10. For the second group, the order was reversed. Results : Within each group pre-post test differences were significant for both the relaxation techniques. The magnitude of net score improvement was greater after SR (7.85% compared to CM (3.95%. Significance levels were P < 0.4 x 10 -9 for SR and P < 0.1 x 10 -3 for CM. The number of wrong attempts also increased significantly on both interventions, even after removing two outlier data points on day 1 in the SR group. Conclusions: Both CM and SR lead to improvement in performance on the DLST. However, these relaxation techniques lead to more wrong cancellation errors.

Research Article Special Issue

African Journals Online (AJOL)

2016-05-15

May 15, 2016 ... corrective exercises to improve static and dynamic balance of supinate ... improve the ability to maintain balance and postural control in ..... Gupta, D., & Nair, M. D. Neurogenic orthostatic hypotension: Chasing "the fall".

Prior exercise speeds pulmonary oxygen uptake kinetics and increases critical power during supine but not upright cycling.

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Goulding, Richie P; Roche, Denise M; Marwood, Simon

2017-09-01

What is the central question of this study? Critical power (CP) represents the highest work rate for which a metabolic steady state is attainable. The physiological determinants of CP are unclear, but research suggests that CP might be related to the time constant of phase II oxygen uptake kinetics (τV̇O2). What is the main finding and its importance? We provide the first evidence that τV̇O2 is mechanistically related to CP. A reduction of τV̇O2 in the supine position was observed alongside a concomitant increase in CP. This effect may be contingent on measures of oxygen availability derived from near-infrared spectroscopy. Critical power (CP) is a fundamental parameter defining high-intensity exercise tolerance and is related to the time constant of phase II pulmonary oxygen uptake kinetics (τV̇O2). To test the hypothesis that this relationship is causal, we determined the impact of prior exercise ('priming') on CP and τV̇O2 in the upright and supine positions. Seventeen healthy men were assigned to either upright or supine exercise groups, whereby CP, τV̇O2 and muscle deoxyhaemoglobin kinetics (τ [HHb] ) were determined via constant-power tests to exhaustion at four work rates with (primed) and without (control) priming exercise at ∼31%Δ. During supine exercise, priming reduced τV̇O2 (control 54 ± 18 s versus primed 39 ± 11 s; P exercise had no effect on τV̇O2 (control 37 ± 12 s versus primed 35 ± 8 s; P = 0.82), τ [HHb] (control 10 ± 5 s versus primed 14 ± 10 s; P = 0.10) or CP (control 235 ± 42 W versus primed 232 ± 35 W; P = 0.57) during upright exercise. The concomitant reduction of τV̇O2 and increased CP following priming in the supine group, effects that were absent in the upright group, provide the first experimental evidence that τV̇O2 is mechanistically related to critical power. The increased τ [HHb+Mb] suggests that this effect was mediated, at least in part, by improved oxygen

Paramagnetic relaxation effects in perturbed angular correlations for arbitrary electronic relaxation time

International Nuclear Information System (INIS)

Chopin, C.; Spanjaard, D.; Hartmann-Boutron, F.

1975-01-01

Previous perturbation treatments of paramagnetic relaxation effects in γγ PAC were limited to the case of very short electronic relaxation times. This limitation is circumvented by invoking a new perturbation theory recently elaborated by Hirst and others for handling relaxation effects in Moessbauer spectra. Under the assumption of spherical electronic relaxation the perturbation factors are computed as functions of certain relaxation parameters which are directly related to the microscopic relaxation Hamiltonian. The results are compared to those of the stochastic theory of Scherer and Blume [fr

Barnacle geese achieve significant energetic savings by changing posture.

Science.gov (United States)

Tickle, Peter G; Nudds, Robert L; Codd, Jonathan R

2012-01-01

Here we report the resting metabolic rate in barnacle geese (Branta leucopsis) and provide evidence for the significant energetic effect of posture. Under laboratory conditions flow-through respirometry together with synchronous recording of behaviour enabled a calculation of how metabolic rate varies with posture. Our principal finding is that standing bipedally incurs a 25% increase in metabolic rate compared to birds sitting on the ground. In addition to the expected decrease in energy consumption of hindlimb postural muscles when sitting, we hypothesise that a change in breathing mechanics represents one potential mechanism for at least part of the observed difference in energetic cost. Due to the significant effect of posture, future studies of resting metabolic rates need to take into account and/or report differences in posture.

THE PRESENCE OF POSTURAL DEFORMITIES OF THE YOUTH DEPENDING ON THE LEVEL OF PARENTS KNOWLADGE ABOUT DEFICIENT BODY POSTURE

Directory of Open Access Journals (Sweden)

Zoran Bogdanović

2007-05-01

Full Text Available The subject of this study is deterimining the presence of postural deformities in sagittal view (defi cient kyphotic and lordotic body posture of the youth depanding on the level of parents knowladge about defi cient body posture. The complete content of the program was conducted in the territory of the city of Kragujevac in several elementary schools, comprising 299 students of the 5th grade and their parents. The object of this study was to determine the number of students with defi cient kyphotic and lordotic body posture, to determine the presence of dis arrangements depanding on the gender and to determine the presence of kyphotic and lordotic deformity depanding on the parents level of information about defi ciant body posture among children. Kyphotic deformity of the examiners of male population is mostly present in the group of parents who are poorly informed about body posture defi ciency. Regarding examiners of female population , the presence of deformation is equally divided on the group of parents who expressed themselves as being very well, those who are undecided and those who are poorly informed. The more signifi cant presence of kyphotic deformity is at examiners of male population than at the examiners of female population while the higher presence of lordotic deformity is at the examiners of female population. Regarding female population we can observe the highest presence of deformation in the group of parents who are undecided while the other groups are very equabal by the presence of deformation. Stated measures impose a statement that it is necessary to continuosly work on both - children education and parents education aiming to recognize posture defi ciency and physical deformation of school and preschool population and all of this with the object of reducing the deformation and on time detecting certain disarrangements and taking adaquate measures for its senctuary

Effects of posture on postoperative pulmonary function

DEFF Research Database (Denmark)

Nielsen, K G; Holte, Kathrine; Kehlet, H

2003-01-01

BACKGROUND: Pulmonary morbidity is still a relevant complication to major surgery despite improvements in surgical technique and anaesthetic methods. Postoperative posture may be a pathogenic factor, but the effects of changes in postoperative posture on pulmonary function have not been reviewed...

Multisensory training for postural sway control in non-injured elderly ...

African Journals Online (AJOL)

Multisensory training for postural sway control in non-injured elderly females. ... Elderly adults demonstrate increased postural sway, which may ultimately lead to falls. ... Keywords: multisensory training, postural sway control, balance ability, ...

Effects of exercise position on the ventilatory responses to exercise in chronic heart failure.

Science.gov (United States)

Armour, W; Clark, A L; McCann, G P; Hillis, W S

1998-09-01

Patients with heart failure frequently complain of orthopnoea. The objective was to assess the ventilatory response of patients with chronic heart failure during erect and supine exercise. Maximal incremental exercise testing with metabolic gas exchange measurements in erect and supine positions conducted in random order. Tertiary referral centre for cardiology. Nine patients with heart failure (aged 61.9+/-6.1 years) and 10 age matched controls (63.8+/-4.6). Metabolic gas exchange measurements. The slope of the relation between ventilation and carbon dioxide production. Ratings of perceived breathlessness during exercise. Oxygen consumption (VO2) and ventilation were higher during erect exercise at each stage in each group. Peak VO2 was [mean (SD)] 17.12 ml/kg/min (4.07) erect vs 12.92 (3.61) supine in the patients (P<0.01) and 22.62 (5.03) erect-supine vs 19.16 (3.78) erect (P<0.01) in the controls. Ratings of perceived exertion were higher in the patients at each stage, but unaffected by posture. There was no difference in the slope of the relation between ventilation and carbon dioxide production between erect and supine exercise 36.39 (6.12) erect vs 38.42 (8.89) supine for patients; 30.05 (4.52) vs 28.80 (3.96) for controls. In this group of patients during exercise, there was no change in the perception of breathlessness, nor the ventilatory response to carbon dioxide production with change in posture, although peak ventilation was greater in the erect position. The sensation of breathlessness may be related to the appropriateness of the ventilatory response to exertion rather than to the absolute ventilation.

Development of the Coordination between Posture and Manual Control

Science.gov (United States)

Haddad, Jeffrey M.; Claxton, Laura J.; Keen, Rachel; Berthier, Neil E.; Riccio, Gary E.; Hamill, Joseph; Van Emmerik, Richard E. A.

2012-01-01

Studies have suggested that proper postural control is essential for the development of reaching. However, little research has examined the development of the coordination between posture and manual control throughout childhood. We investigated the coordination between posture and manual control in children (7- and 10-year-olds) and adults during…

Cerebellar transcranial direct current stimulation improves adaptive postural control.

Science.gov (United States)

Poortvliet, Peter; Hsieh, Billie; Cresswell, Andrew; Au, Jacky; Meinzer, Marcus

2018-01-01

Rehabilitation interventions contribute to recovery of impaired postural control, but it remains a priority to optimize their effectiveness. A promising strategy may involve transcranial direct current stimulation (tDCS) of brain areas involved in fine-tuning of motor adaptation. This study explored the effects of cerebellar tDCS (ctDCS) on postural recovery from disturbance by Achilles tendon vibration. Twenty-eight healthy volunteers participated in this sham-ctDCS controlled study. Standing blindfolded on a force platform, four trials were completed: 60 s quiet standing followed by 20 min active (anodal-tDCS, 1 mA, 20 min, N = 14) or sham-ctDCS (40 s, N = 14) tDCS; three quiet standing trials with 15 s of Achilles tendon vibration and 25 s of postural recovery. Postural steadiness was quantified as displacement, standard deviation and path derived from the center of pressure (COP). Baseline demographics and quiet standing postural steadiness, and backwards displacement during vibration were comparable between groups. However, active-tDCS significantly improved postural steadiness during vibration and reduced forward displacement and variability in COP derivatives during recovery. We demonstrate that ctDCS results in short-term improvement of postural adaptation in healthy individuals. Future studies need to investigate if multisession ctDCS combined with training or rehabilitation interventions can induce prolonged improvement of postural balance. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Postural habits of young adults and possibilities of modification.

Science.gov (United States)

Nowotny-Czupryna, Olga; Czupryna, Krzysztof; Bąk, Krzysztof; Wróblewska, Ewa; Rottermund, Jerzy

2013-01-01

The aim of the study was to assess postural habits in young, healthy people, identify correlations between postural errors and pain and attempt to modify bad habits. 144 people, aged 18-23 were enrolled. The intervention consisted of 4 stages: Stage 1 - identification of postural habits, description of responses to stress, back pain frequency and intensity (Jackson & Moskowitz); Stage 2 - correction of habitual position with the help of a physiotherapist, briefing about ergonomic everyday behaviours and consequences of continued non-ergonomic behaviours, Stage 3 - follow-up examination: self-assessment of changes, evaluation of the effects of modifications, determination of causes for discontinuing the behaviour modification programme, where applicable; and Stage 4 - final examination, assessment of results. Correlations were sought between inappropriate postural behaviour in various positions and between non-ergonomic postural behaviour and pain location and response to stress. Statistical analysis was carried out with Excel and Statistica v. 7.1. A non-parametric χ(2) test was used at phabit. 3. An attempt to modify non-ergonomic postural behaviours usually results in pain, which may act as a demotivating factor. 4. Discomfort associated with the modification of habitual postural behaviours is reduced after 3-4 months of regular training.

Postural stability in young and old women

DEFF Research Database (Denmark)

Jørgensen, Martin Grønbech

at an early stage, good knowledge and sensitive measurements of postural stability are essential. In addition, in order to develop effective intervention strategies such knowledge is of major importance. However, no single postural stability parameter has effectively been able to identify individuals at risk...... of falling. Hence, there is a strong need for development and identification of sensitive postural sway parameters in various demographic groups. The aim of this study was to explore differences in postural stability between physically active old (O) and young (Y) women using newly developed sway parameters....... METHODS AND MATERIALS: Center of pressure (CoP) excursion was measured (100 Hz) by force plate (AMTI) analysis in old (72.5±6.3 years) and young (25.8±1.6 years) women during static 2-leg (bilateral) and 1-leg (unilateral) standing (15-s) with eyes opened. RESULTS: O demonstrated elevated CoP sway length...

Coupling between arterial and venous cerebral blood flow during postural change

DEFF Research Database (Denmark)

Ogoh, Shigehiko; Washio, Takuro; Sasaki, Hiroyuki

2016-01-01

In supine humans the main drainage from the brain is through the internal jugular vein (IJV) but the vertebral veins (VV) become important during orthostatic stress because the IJV is partially collapsed. To identify the effect of this shift in venous drainage from the brain on the cerebral...... blood flow (r=0.649, P=0.004) and the two flows were coupled during manipulation of the end-tidal CO2 tension (supine, r=0.551, P=0.004; seated, r=0.612, P

Classifying Transition Behaviour in Postural Activity Monitoring

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James BRUSEY

2009-10-01

Full Text Available A few accelerometers positioned on different parts of the body can be used to accurately classify steady state behaviour, such as walking, running, or sitting. Such systems are usually built using supervised learning approaches. Transitions between postures are, however, difficult to deal with using posture classification systems proposed to date, since there is no label set for intermediary postures and also the exact point at which the transition occurs can sometimes be hard to pinpoint. The usual bypass when using supervised learning to train such systems is to discard a section of the dataset around each transition. This leads to poorer classification performance when the systems are deployed out of the laboratory and used on-line, particularly if the regimes monitored involve fast paced activity changes. Time-based filtering that takes advantage of sequential patterns is a potential mechanism to improve posture classification accuracy in such real-life applications. Also, such filtering should reduce the number of event messages needed to be sent across a wireless network to track posture remotely, hence extending the system’s life. To support time-based filtering, understanding transitions, which are the major event generators in a classification system, is a key. This work examines three approaches to post-process the output of a posture classifier using time-based filtering: a naïve voting scheme, an exponentially weighted voting scheme, and a Bayes filter. Best performance is obtained from the exponentially weighted voting scheme although it is suspected that a more sophisticated treatment of the Bayes filter might yield better results.

Barnacle geese achieve significant energetic savings by changing posture.

Directory of Open Access Journals (Sweden)

Peter G Tickle

Full Text Available Here we report the resting metabolic rate in barnacle geese (Branta leucopsis and provide evidence for the significant energetic effect of posture. Under laboratory conditions flow-through respirometry together with synchronous recording of behaviour enabled a calculation of how metabolic rate varies with posture. Our principal finding is that standing bipedally incurs a 25% increase in metabolic rate compared to birds sitting on the ground. In addition to the expected decrease in energy consumption of hindlimb postural muscles when sitting, we hypothesise that a change in breathing mechanics represents one potential mechanism for at least part of the observed difference in energetic cost. Due to the significant effect of posture, future studies of resting metabolic rates need to take into account and/or report differences in posture.

The impact of arm position on the measurement of orthostatic blood pressure.

Science.gov (United States)

Guss, David A; Abdelnur, Diego; Hemingway, Thomas J

2008-05-01

Blood pressure is a standard vital sign in patients evaluated in an Emergency Department. The American Heart Association has recommended a preferred position of the arm and cuff when measuring blood pressure. There is no formal recommendation for arm position when measuring orthostatic blood pressure. The objective of this study was to assess the impact of different arm positions on the measurement of postural changes in blood pressure. This was a prospective, unblinded, convenience study involving Emergency Department patients with complaints unrelated to cardiovascular instability. Repeated blood pressure measurements were obtained using an automatic non-invasive device with each subject in a supine and standing position and with the arm parallel and perpendicular to the torso. Orthostatic hypotension was defined as a difference of >or= 20 mm Hg systolic or >or= 10 mm Hg diastolic when subtracting standing from supine measurements. There were four comparisons made: group W, arm perpendicular supine and standing; group X, arm parallel supine and standing; group Y, arm parallel supine and perpendicular standing; and group Z, arm perpendicular supine and parallel standing. There were 100 patients enrolled, 55 men, mean age 44 years. Four blood pressure measurements were obtained on each patient. The percentage of patients meeting orthostatic hypotension criteria in each group was: W systolic 6% (95% CI 1%, 11%), diastolic 4% (95% CI 0%, 8%), X systolic 8% (95% CI 3%, 13%), diastolic 9% (95% CI 3%, 13%), Y systolic 19% (95% CI 11%, 27%), diastolic 30% (95% CI 21%, 39%), Z systolic 2% (95% CI 0%, 5%), diastolic 2% (95% CI 0%, 5%). Comparison of Group Y vs. X, Z, and W was statistically significant (p postural changes in blood pressure. The combination of the arm parallel when supine and perpendicular when standing may significantly overestimate the orthostatic change. Arm position should be held constant in supine and standing positions when assessing for orthostatic

The relationship between the stomatognathic system and body posture

Directory of Open Access Journals (Sweden)

Antonino Cuccia

2009-01-01

Full Text Available In recent years, many researchers have investigated the various factors that can influence body posture: mood states, anxiety, head and neck positions, oral functions (respiration, swallowing, oculomotor and visual systems, and the inner ear. Recent studies indicate a role for trigeminal afferents on body posture, but this has not yet been demonstrated conclusively. The present study aims to review the papers that have shown a relationship between the stomatognathic system and body posture. These studies suggest that tension in the stomatognathic system can contribute to impaired neural control of posture. Numerous anatomical connections between the stomatognathic system's proprioceptive inputs and nervous structures are implicated in posture (cerebellum, vestibular and oculomotor nuclei, superior colliculus. If the proprioceptive information of the stomatognathic system is inaccurate, then head control and body position may be affected. In addition, the present review discusses the role the myofascial system plays in posture. If confirmed by further research, these considerations can improve our understanding and treatment of muscular-skeletal disorders that are associated with temporomandibular joint disorders, occlusal changes, and tooth loss.

The Relationship Between the Stomatognathic System and Body Posture

Science.gov (United States)

Cuccia, Antonino; Caradonna, Carola

2009-01-01

In recent years, many researchers have investigated the various factors that can influence body posture: mood states, anxiety, head and neck positions, oral functions (respiration, swallowing), oculomotor and visual systems, and the inner ear. Recent studies indicate a role for trigeminal afferents on body posture, but this has not yet been demonstrated conclusively. The present study aims to review the papers that have shown a relationship between the stomatognathic system and body posture. These studies suggest that tension in the stomatognathic system can contribute to impaired neural control of posture. Numerous anatomical connections between the stomatognathic system’s proprioceptive inputs and nervous structures are implicated in posture (cerebellum, vestibular and oculomotor nuclei, superior colliculus). If the proprioceptive information of the stomatognathic system is inaccurate, then head control and body position may be affected. In addition, the present review discusses the role the myofascial system plays in posture. If confirmed by further research, these considerations can improve our understanding and treatment of muscular-skeletal disorders that are associated with temporomandibular joint disorders, occlusal changes, and tooth loss. PMID:19142553

Do older adults perceive postural constraints for reach estimation?

Science.gov (United States)

Cordova, Alberto; Gabbard, Carl

2014-01-01

BACKGROUND/STUDY CONTEXT: Recent evidence indicates that older persons have difficulty mentally representing intended movements. Furthermore, in an estimation of reach paradigm using motor imagery, a form of mental representation, older persons significantly overestimated their ability compared with young adults. The authors tested the notion that older adults may also have difficulty perceiving the postural constraints associated with reach estimation. The authors compared young (Mage = 22 years) and older (Mage = 67) adults on reach estimation while seated and in a more postural demanding standing and leaning forward position. The expectation was a significant postural effect with the standing condition, as evidenced by reduced overestimation. Whereas there was no difference between groups in the seated condition (both overestimated), older adults underestimated whereas the younger group once again overestimated in the standing condition. From one perspective, these results show that older adults do perceive postural constraints in light of their own physical capabilities. That is, that group perceived greater postural demands with the standing posture and elected to program a more conservative strategy, resulting in underestimation.

Otolith and Vertical Canal Contributions to Dynamic Postural Control

Science.gov (United States)

Black, F. Owen

1999-01-01

The objective of this project is to determine: 1) how do normal subjects adjust postural movements in response to changing or altered otolith input, for example, due to aging? and 2) how do patients adapt postural control after altered unilateral or bilateral vestibular sensory inputs such as ablative inner ear surgery or ototoxicity, respectively? The following hypotheses are under investigation: 1) selective alteration of otolith input or abnormalities of otolith receptor function will result in distinctive spatial, frequency, and temporal patterns of head movements and body postural sway dynamics. 2) subjects with reduced, altered, or absent vertical semicircular canal receptor sensitivity but normal otolith receptor function or vice versa, should show predictable alterations of body and head movement strategies essential for the control of postural sway and movement. The effect of altered postural movement control upon compensation and/or adaptation will be determined. These experiments provide data for the development of computational models of postural control in normals, vestibular deficient subjects and normal humans exposed to unusual force environments, including orbital space flight.

A comparison of three observational techniques for assessing postural loads in industry.

Science.gov (United States)

Kee, Dohyung; Karwowski, Waldemar

2007-01-01

This study aims to compare 3 observational techniques for assessing postural load, namely, OWAS, RULA, and REBA. The comparison was based on the evaluation results generated by the classification techniques using 301 working postures. All postures were sampled from the iron and steel, electronics, automotive, and chemical industries, and a general hospital. While only about 21% of the 301 postures were classified at the action category/level 3 or 4 by both OWAS and REBA, about 56% of the postures were classified into action level 3 or 4 by RULA. The inter-method reliability for postural load category between OWAS and RULA was just 29.2%, and the reliability between RULA and REBA was 48.2%. These results showed that compared to RULA, OWAS, and REBA generally underestimated postural loads for the analyzed postures, irrespective of industry, work type, and whether or not the body postures were in a balanced state.

VALIDITY AND REPRODUCIBILITY OF MEASURING THE KINEMATIC COUPLING BEHAVIOR OF CALCANEAL PRONATION/SUPINATION AND SHANK ROTATION DURING WEIGHT BEARING USING AN OPTICAL THREE-DIMENSIONAL MOTION ANALYSIS SYSTEM

Directory of Open Access Journals (Sweden)

Masahiro Edo

2017-12-01

Full Text Available Background: It’s important to understand the kinematic coupling of calcaneus and shank to optimize the pathological movement of the lower extremity. However, the quantitative indicator to show the kinematic coupling hasn’t been clarified. We measured the angles of calcaneal pronation-to-supination and shank rotation during pronation and supination of both feet in standing position and devised a technique to quantify the kinematic coupling behavior of calcaneal pronation/supination and shank rotation as the linear regression coefficient (kinematic chain ratio: KCR of those measurements. Therefore, we verified the validity and reproducibility of this technique. Methods: This study is a non-comparative cross-sectional study. The KCR, which is an outcome, was measured using an optical three-dimensional motion analysis system in 10 healthy subjects. The coefficient of determination (R² was calculated for the linear regression equation of the angle of calcaneal pronation-to-supination and angle of shank rotation, and the intraclass correlation coefficient (ICC [1,1] was calculated for the KCR during foot pronation and foot supination and for the KCR measured on different days. And also, skin movement artifacts were investigated by measurement of the displacement of bone and body surface markers in one healthy subject. Results: The linear regression equation of calcaneal pronation/supination and the angle of shank rotation included R²≥0.9 for all subjects. The KCR on foot pronation and supination had an ICC(1,1 of 0.95. The KCR measured on different days had an ICC(1,1 of 0.72. Skin movement artifacts were within the allowable range. Conclusion: The validity and reproducibility of this technique were largely good, and the technique can be used to quantify kinematic coupling behavior.

Holding a handle for balance during continuous postural perturbations – immediate and transitionary effects on whole body posture

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Jernej Camernik

2016-09-01

Full Text Available When balance is exposed to perturbations, hand contacts are often used to assist postural control. We investigated the immediate and the transitionary effects of supportive hand contacts during continuous anteroposterior perturbations of stance by automated waist-pulls. Ten young adults were perturbed for five minutes and required to maintain balance by holding to a stationary, shoulder-high handle and following its removal. Centre of pressure (COP displacement, hip, knee, and ankle angles, leg and trunk muscle activity and handle contact forces were acquired. The analysis of results show that COP excursions are significantly smaller when the subjects utilize supportive hand contact and that the displacement of COP is strongly correlated to the perturbation force and significantly larger in the anterior than posterior direction. Regression analysis of hand forces revealed that subjects utilized the hand support significantly more during the posterior than anterior perturbations. Moreover, kinematical analysis showed that utilization of supportive hand contacts alters posture of the whole body and that postural readjustments after the release of the handle occur at different time scales in the hip, knee, and ankle joints. Overall, our findings show that supportive hand contacts are efficiently used for balance control during continuous postural perturbations and that utilization of a handle has significant immediate and transitionary effects on whole body posture.

Rupture of the Distal Biceps Tendon Combined with a Supinator Muscle Tear in a 51-Year-Old Woman: A Case Report

OpenAIRE

Nayyar, Samir; Quirno, Martin; Hasan, Saqib; Rybak, Leon; Meislin, Robert J.

2011-01-01

Distal biceps tendon rupture is a relatively uncommon occurrence in the general female population, and to our knowledge, has not been reported in association with a supinator muscle tear. We report a case of 51-year-old woman who experienced sharp pain in her forearm and elbow after lifting a heavy object. History and physical examination raised suspicion for a distal biceps tendon rupture. MRI imaging determined a combined distal biceps tendon tear with a supinator muscle tear with subsequen...

Variation in posture quality across musical instruments and its impact during performances.

Science.gov (United States)

Blanco-Piñeiro, Patricia; Díaz-Pereira, M Pino; Martínez Vidal, Aurora

2018-06-01

Bad posture increases the risk that a musician may suffer from musculoskeletal disorders. This study compared posture quality required by different instruments or families of instruments. Using an ad-hoc postural observation instrument embracing 11 postural variables, four experts evaluated the postures of 100 students attending a Spanish higher conservatory of music. The agreement of the experts' evaluations was statistically confirmed by a Cohen's κ value between 0.855 and 1.000 and a Kendall value between 0.709 and 1.000 (p instrument families and seated posture with respect to pelvic attitude, dorsal curvature and head alignment in both sagittal and frontal planes. This analysis also showed an association between instrument families and standing posture with respect to the frontal plane of the axis of gravity, pelvic attitude, head alignment in the frontal plane, the sagittal plane of the shoulders and overall posture. While certain postural defects appear to be common to all families of instruments, others are more characteristic of some families than others. The instrument associated with the best posture quality was the bagpipe, followed by percussion and strings.

Arterial wave reflection decreases gradually from supine to upright

DEFF Research Database (Denmark)

van den Bogaard, Bas; Westerhof, Berend E; Best, Hendrik

2011-01-01

BACKGROUND. An increase in total peripheral resistance (TPR) usually increases arterial wave reflection. During passive head-up tilt (HUT), however, arterial wave reflection decreases with increasing TPR. This study addressed whether arterial wave reflection gradually decreases during HUT. METHODS....... In 10 healthy volunteers (22-39 years, nine males), we recorded finger arterial pressures in supine position (0°), and 30°and 70°degrees HUT and active standing (90°). Aortic pressure was constructed from the finger pressure signal and hemodynamics were calculated. Arterial wave reflection...... from 0.9 dyn s/cm(5) at 0? to 1.2, 1.4 and 1.4 dyn s/cm(5) at 30°, 70° and 90° (p wave reflection...

Face-down positioning versus non-supine positioning in macular hole surgery

DEFF Research Database (Denmark)

Alberti, Mark; Dornonville de la Cour, Morten

2015-01-01

AIM: To evaluate the full thickness macular hole (FTMH) closure rate in patients positioning non-supine (NSP) compared with patients positioning face-down (FDP). METHODS: We retrospectively reviewed two FTMH case series-postoperative positioning was FDP and NSP, respectively. All eyes were...... group fully complied with the recommended positioning protocol. CONCLUSIONS: Results from consistent FTMH repair indicate similar anatomical success rates in FDP and NSP groups, suggesting that FDP is unnecessary. Objective monitoring of positioning would be beneficial in future FTMH studies to be able...

Supine position and nonmodifiable risk factors for ventilator-associated pneumonia in trauma patients.

Science.gov (United States)

Michetti, Christopher P; Prentice, Heather A; Rodriguez, Jennifer; Newcomb, Anna

2017-02-01

We studied trauma-specific conditions precluding semiupright positioning and other nonmodifiable risk factors for their influence on ventilator-associated pneumonia (VAP). We performed a retrospective study at a Level I trauma center from 2008 to 2012 on ICU patients aged ≥15, who were intubated for more than 2 days. Using backward logistic regression, a composite of 4 factors (open abdomen, acute spinal cord injury, spine fracture, spine surgery) that preclude semiupright positioning (supine composite) and other variables were analyzed. In total, 77 of 374 (21%) patients had VAP. Abbreviated Injury Score head/neck greater than 2 (odds ratio [OR] 2.79, P = .006), esophageal obturator airway (OR 4.25, P = .015), red cell/plasma transfusion in the first 2 intensive care unit days (OR 2.59, P = .003), and 11 or more ventilator days (OR 17.38, P VAP risk factors, whereas supine composite, scene vs emergency department airway intervention, brain injury, and coma were not. Factors that may temporarily preclude semiupright positioning in intubated trauma patients were not associated with a higher risk for VAP. Copyright © 2016 Elsevier Inc. All rights reserved.

Recognition of dance-like actions: memory for static posture or dynamic movement?

Science.gov (United States)

Vicary, Staci A; Robbins, Rachel A; Calvo-Merino, Beatriz; Stevens, Catherine J

2014-07-01

Dance-like actions are complex visual stimuli involving multiple changes in body posture across time and space. Visual perception research has demonstrated a difference between the processing of dynamic body movement and the processing of static body posture. Yet, it is unclear whether this processing dissociation continues during the retention of body movement and body form in visual working memory (VWM). When observing a dance-like action, it is likely that static snapshot images of body posture will be retained alongside dynamic images of the complete motion. Therefore, we hypothesized that, as in perception, posture and movement would differ in VWM. Additionally, if body posture and body movement are separable in VWM, as form- and motion-based items, respectively, then differential interference from intervening form and motion tasks should occur during recognition. In two experiments, we examined these hypotheses. In Experiment 1, the recognition of postures and movements was tested in conditions in which the formats of the study and test stimuli matched (movement-study to movement-test, posture-study to posture-test) or mismatched (movement-study to posture-test, posture-study to movement-test). In Experiment 2, the recognition of postures and movements was compared after intervening form and motion tasks. These results indicated that (1) the recognition of body movement based only on posture is possible, but it is significantly poorer than recognition based on the entire movement stimulus, and (2) form-based interference does not impair memory for movements, although motion-based interference does. We concluded that, whereas static posture information is encoded during the observation of dance-like actions, body movement and body posture differ in VWM.

[Occlusion and posture: is there evidence of correlation?].

Science.gov (United States)

Michelotti, A; Manzo, P; Farella, M; Martina, R

1999-11-01

The observation that the masticatory system and the postural body regulating system are anatomically and functionally related, has led to postulate several hypotheses of correlation between occlusal and postural disturbances. In the last decade, these arguments have gained a great social impact, also because they have been broadly spread by the mass-media. As a consequence, there has been a growing number of patients seeking concomitant occlusal and postural treatments. The aim of this study was to review critically the current evidence of correlation between the two systems; this in order to address clinical issues for the management of patients. Methodology of the studies reviewed has been evaluated according to the criteria suggested by Storey and Rugh 20 rif. Although there are some evidences of correlation between occlusion and posture, this appears limited to the cranio-cervical tract of the column and tends to disappear when descending in cranio-caudal direction. On the basis of this review of the literature, it's not advisable to treat postural imbalance by means of occlusal treatment or vice versa, particularly if the therapeutic modalities are irreversible.

Image to physical space registration of supine breast MRI for image guided breast surgery

Science.gov (United States)

Conley, Rebekah H.; Meszoely, Ingrid M.; Pheiffer, Thomas S.; Weis, Jared A.; Yankeelov, Thomas E.; Miga, Michael I.

2014-03-01

Breast conservation therapy (BCT) is a desirable option for many women diagnosed with early stage breast cancer and involves a lumpectomy followed by radiotherapy. However, approximately 50% of eligible women will elect for mastectomy over BCT despite equal survival benefit (provided margins of excised tissue are cancer free) due to uncertainty in outcome with regards to complete excision of cancerous cells, risk of local recurrence, and cosmesis. Determining surgical margins intraoperatively is difficult and achieving negative margins is not as robust as it needs to be, resulting in high re-operation rates and often mastectomy. Magnetic resonance images (MRI) can provide detailed information about tumor margin extents, however diagnostic images are acquired in a fundamentally different patient presentation than that used in surgery. Therefore, the high quality diagnostic MRIs taken in the prone position with pendant breast are not optimal for use in surgical planning/guidance due to the drastic shape change between preoperative images and the common supine surgical position. This work proposes to investigate the value of supine MRI in an effort to localize tumors intraoperatively using image-guidance. Mock intraoperative setups (realistic patient positioning in non-sterile environment) and preoperative imaging data were collected from a patient scheduled for a lumpectomy. The mock intraoperative data included a tracked laser range scan of the patient's breast surface, tracked center points of MR visible fiducials on the patient's breast, and tracked B-mode ultrasound and strain images. The preoperative data included a supine MRI with visible fiducial markers. Fiducial markers localized in the MRI were rigidly registered to their mock intraoperative counterparts using an optically tracked stylus. The root mean square (RMS) fiducial registration error using the tracked markers was 3.4mm. Following registration, the average closest point distance between the MR

Comparison of Radiation Treatment Plans for Breast Cancer between 3D Conformal in Prone and Supine Positions in Contrast to VMAT and IMRT Supine Positions

Science.gov (United States)

Bejarano Buele, Ana Isabel

The treatment regimen for breast cancer patients typically involves Whole Breast Irradiation (WBI). The coverage and extent of the radiation treatment is dictated by location of tumor mass, breast tissue distribution, involvement of lymph nodes, and other factors. The current standard treatment approach used at our institution is a 3D tangential beam geometry, which involves two fields irradiating the breast, or a four field beam arrangement covering the whole breast and involved nodes, while decreasing the dose to organs as risk (OARs) such as the lung and heart. The coverage of these targets can be difficult to achieve in patients with unfavorable thoracic geometries, especially in those cases in which the planning target volume (PTV) is extended to the chest wall. It is a well-known fact that exposure of the heart to ionizing radiation has been proved to increase the subsequent rate of ischemic heart disease. In these cases, inverse planned treatments have become a proven alternative to the 3D approach. The goal of this research project is to evaluate the factors that affect our current techniques as well as to adapt the development of inverse modulated techniques for our clinic, in which breast cancer patients are one of the largest populations treated. For this purpose, a dosimetric comparison along with the evaluation of immobilization devices was necessary. Radiation treatment plans were designed and dosimetrically compared for 5 patients in both, supine and prone positions. For 8 patients, VMAT and IMRT plans were created and evaluated in the supine position. Skin flash incorporation for inverse modulated plans required measurement of the surface dose as well as an evaluation of breast volume changes during a treatment course. It was found that prone 3D conformal plans as well as the VMAT and IMRT plans are generally superior in sparing OARs to supine plans with comparable PTV coverage. Prone setup leads to larger shifts in breast volume as well as in

Screening initial entry training trainees for postural faults and low back or hip pain.

Science.gov (United States)

Lane, John R

2014-01-01

The frequency of postural faults and postural awareness in military trainees has not been assessed. Five hundred Soldiers entering Advanced Individual Training were screened for standing posture and completed an anonymous questionnaire during inprocessing. Postural faults were identified in 202 subjects. Chi square analysis demonstrated a relationship between posture observed and posture reported: 87% of subjects with postural faults were unaware of postural faults; 12% with proper posture reported having poor posture. Subjects reported comparable frequencies of back pain and hip pain with postural faults (33.2%, 21.2%) and without faults (28.5%, 14.7%). Anonymous reporting was higher than formal reporting and requests for care during the same period (37% vs 3.4%).

Assessment of postural instability in patients with Parkinson's disease.

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Błaszczyk, J W; Orawiec, R; Duda-Kłodowska, D; Opala, G

2007-10-01

Postural instability is one of the most disabling features of idiopathic Parkinson's disease (PD). In this study, we focused on postural instability as the main factor predisposing parkinsonians to falls. For this purpose, changes in sway characteristics during quiet stance due to visual feedback exclusion were studied. We searched for postural sway measures that could be potential discriminators for an increased fall risk. A group of 110 subjects: 55 parkinsonians (Hoehn and Yahr: 1-3), and 55 age-matched healthy volunteers participated in the experiment. Their spontaneous sway characteristics while standing quiet with eyes open and eyes closed were analyzed. We found that an increased mediolateral sway and sway area while standing with eyes closed are characteristic of parkinsonian postural instability and may serve to quantify well a tendency to fall. These sway indices significantly correlated with disease severity rated both by the Hoehn and Yahr scale as well as by the Motor Section of the UPDRS. A forward shift of a mean COP position in parkinsonians which reflects their flexed posture was also significantly greater to compare with the elderly subjects and exhibited a high sensitivity to visual conditions. Both groups of postural sway abnormalities identified here may be used as accessible and reliable measures which allow for quantitative assessment of postural instability in Parkinson's disease.

Exercise and Posture

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... About Spondylitis › Treatment Information › Exercise & Posture Print Page Exercise Exercise is an integral part of any spondylitis ... For First Responders For Chiropractors Research Article Archive Exercise Guidelines Having an exercise program that accomplishes your ...

[The impact of different sports on posture regulation].

Science.gov (United States)

Schwesig, R; Kluttig, A; Leuchte, S; Becker, S; Schmidt, H; Esperer, H D

2009-09-01

Previous work has suggested that both the level of activity and the type of sport may have a major impact on postural control. However, no systematic investigation has been performed regarding the various types of professional sports. Particularly, the impact of competitional sports on the postural subsystems has not been elucidated so far. The aim of this study was to investigate the influence of the major professional sport types, such as handball, gymnastics, swimming, and shooting, on the subsystems of postural control. We also tested the hypothesis that specific types of sport have specific effects on postural regulation. 155 competitive male and female athletes (handball: n = 30; gymnastics: n = 44; swimming: n = 50; shooting: n = 31), and 34 age- and gender-matched controls were investigated using the Interactive Balance System (IBS; Tetrax Inc., Ramat Gan, Israel). The following spectral and time-domain indices were determined: power in the following frequency bands: P(F1) (0.03 - 0.1 Hz), P(F)(2 - 4) (0.1 - 0.5 Hz), P(F)(5 - 6) (0.5 - 1.0 Hz), P(F)(7 - 8) (> 1.0 Hz), stability index (STABI), and synchronisation index (SYN). Shooting athletes exhibited significantly smaller values of P(F1) (p = 0.003), P(F)(2 - 4) (p sports exert different effects on the various subsystems of posture control, where especially shooting competitors demonstrate a significantly better posture regulation. Those effects can be parameterised and quantified with the IBS which thus enables an efficient and purposeful training. Furthermore, the IBS is highly suitable for aptitude screening in sports with high posture regulatory demands (shooting competitions, gymnastics, diving etc.). Copyright Georg Thieme Verlag KG Stuttgart . New York .

Ultrasound and supine chest radiograph in road traffic accident patients: a reliable and convenient way to diagnose pleural effusion

International Nuclear Information System (INIS)

Mumtaz, U.; Zahur, Z.; Raza, M.A.

2017-01-01

Background: Portable bed side ultrasound and supine chest radiograph of 80 traumatic patients excluding very clinically unstable patients who subsequently underwent CT scan chest was done for traumatic effusion showing that ultrasound had a higher sensitivity than CXR, 88.23% and 77.94%, respectively, and a similar specificity of 100% and 100%, respectively. Objective of the study is to compare the diagnostic accuracy of high resolution ultrasound and supine chest x-ray in detection of pleural effusion in road traffic accident patients keeping plain CT chest as gold standard. Methods: This study was conducted in PIMS and PAEC General Hospital, Islamabad from 1st January to 15th December 2015. The current study examined total of 80 trauma (blunt and penetrating) patients coming to emergency departments of both hospitals specifically those who had road traffic accident history. Their portable bed side ultrasound and supine chest radiograph were performed for assessing pleural effusion and subsequently CT scan chest was done for confirmation as it's a gold standard. Results: Using CT findings as gold standard the sensitivity, specificity, positive predictive value and negative predictive value was assessed for both ultrasonography and chest radiography and found to be 88.23%,100%, 100%, 40% and 77.94%, 100%, 100%, 55.55% respectively with diagnostic accuracy of ultrasound 90% as compared to 81.25% for supine chest x-rays when compared with gold standard. Conclusion: Ultrasound and chest x-ray can be used as a useful and suitable adjunct to CT in road traffic accident patients as these are easily available, non-invasive, no contrast required, can be performed on bed side and carries no or little radiation risk. (author)

Eye Movements Affect Postural Control in Young and Older Females.

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Thomas, Neil M; Bampouras, Theodoros M; Donovan, Tim; Dewhurst, Susan

2016-01-01

Visual information is used for postural stabilization in humans. However, little is known about how eye movements prevalent in everyday life interact with the postural control system in older individuals. Therefore, the present study assessed the effects of stationary gaze fixations, smooth pursuits, and saccadic eye movements, with combinations of absent, fixed and oscillating large-field visual backgrounds to generate different forms of retinal flow, on postural control in healthy young and older females. Participants were presented with computer generated visual stimuli, whilst postural sway and gaze fixations were simultaneously assessed with a force platform and eye tracking equipment, respectively. The results showed that fixed backgrounds and stationary gaze fixations attenuated postural sway. In contrast, oscillating backgrounds and smooth pursuits increased postural sway. There were no differences regarding saccades. There were also no differences in postural sway or gaze errors between age groups in any visual condition. The stabilizing effect of the fixed visual stimuli show how retinal flow and extraocular factors guide postural adjustments. The destabilizing effect of oscillating visual backgrounds and smooth pursuits may be related to more challenging conditions for determining body shifts from retinal flow, and more complex extraocular signals, respectively. Because the older participants matched the young group's performance in all conditions, decreases of posture and gaze control during stance may not be a direct consequence of healthy aging. Further research examining extraocular and retinal mechanisms of balance control and the effects of eye movements, during locomotion, is needed to better inform fall prevention interventions.

[Self-evaluation of posture by elderly people with or without thoracic kyphosis].

Science.gov (United States)

Gasparotto, Lívia Pimenta Renó; Reis, Camila Costa Ibiapina; Ramos, Luiz Roberto; Santos, José Francisco Quirino Dos

2012-03-01

This article lists the differences between self-perception of body posture among the elderly suffering from postural alterations or not, in order to ascertain whether self-evaluation of posture can lead to preventive measures. Eighteen cases from the elderly population participated in the EPIDOSO project at UNIFESP and were subjected to postural evaluation. Postures were photographed and copies given to the participants and their subsequent comments were analyzed by the qualitative method. The narratives were taped and cataloguedusingthe technique of theoretical axial and selective coding from the perspective of symbolic interactionism. A passive attitude was identified among the elderly in relation to postural alterations. There is a distortion of body image by those with postural deviation. Participants with adequate spinal alignment were more conscious about body posture and the importance of this being assimilated in the phases prior to aging. The adoption of postural self-care seems to occur in the earlier stages of aging and preventive measures should be implemented at this stage. Lack of concern about posture is linked to the concept of the elderly regarding the notion that aging is, in itself, the accumulation of inevitably simultaneous or successive dysfunctions.

Posture-Motor and Posture-Ideomotor Dual-Tasking: A Putative Marker of Psychomotor Retardation and Depressive Rumination in Patients With Major Depressive Disorder.

Science.gov (United States)

Aftanas, Lyubomir I; Bazanova, Olga M; Novozhilova, Nataliya V

2018-01-01

Background: Recent studies have demonstrated that the assessment of postural performance may be a potentially reliable and objective marker of the psychomotor retardation (PMR) in the major depressive disorder (MDD). One of the important facets of MDD-related PMR is reflected in disrupted central mechanisms of psychomotor control, heavily influenced by compelling maladaptive depressive rumination. In view of this we designed a research paradigm that included sequential execution of simple single-posture task followed by more challenging divided attention posture tasks, involving concurring motor and ideomotor workloads. Another difficulty dimension assumed executing of all the tasks with eyes open (EO) (easy) and closed (EC) (difficult) conditions. We aimed at investigating the interplay between the severity of MDD, depressive rumination, and efficiency of postural performance. Methods: Compared with 24 age- and body mass index-matched healthy controls (HCs), 26 patients with MDD sequentially executed three experimental tasks: (1) single-posture task of maintaining a quiet stance (ST), (2) actual posture-motor dual task (AMT); and (3) mental/imaginary posture-motor dual task (MMT). All the tasks were performed in the EO and the EC conditions. The primary dependent variable was the amount of kinetic energy ( E ) expended for the center of pressure deviations (CoPDs), whereas the absolute divided attention cost index showed energy cost to the dual-tasking vs. the single-posture task according to the formula: Δ E = ( E Dual-task - E Single-task ). Results: The signs of PMR in the MDD group were objectively indexed by deficient posture control in the EC condition along with overall slowness of fine motor and ideomotor activity. Another important and probably more challenging feature of the findings was that the posture deficit manifested in the ST condition was substantially and significantly attenuated in the MMT and AMT performance dual-tasking activity. A multiple

Body surface posture evaluation: construction, validation and protocol of the SPGAP system (Posture evaluation rotating platform system).

Science.gov (United States)

Schwertner, Debora Soccal; Oliveira, Raul; Mazo, Giovana Zarpellon; Gioda, Fabiane Rosa; Kelber, Christian Roberto; Swarowsky, Alessandra

2016-05-04

Several posture evaluation devices have been used to detect deviations of the vertebral column. However it has been observed that the instruments present measurement errors related to the equipment, environment or measurement protocol. This study aimed to build, validate, analyze the reliability and describe a measurement protocol for the use of the Posture Evaluation Rotating Platform System (SPGAP, Brazilian abbreviation). The posture evaluation system comprises a Posture Evaluation Rotating Platform, video camera, calibration support and measurement software. Two pilot studies were carried out with 102 elderly individuals (average age 69 years old, SD = ±7.3) to establish a protocol for SPGAP, controlling the measurement errors related to the environment, equipment and the person under evaluation. Content validation was completed with input from judges with expertise in posture measurement. The variation coefficient method was used to validate the measurement by the instrument of an object with known dimensions. Finally, reliability was established using repeated measurements of the known object. Expert content judges gave the system excellent ratings for content validity (mean 9.4 out of 10; SD 1.13). The measurement of an object with known dimensions indicated excellent validity (all measurement errors reality. To verify the images of objects with known dimensions the values for the width and height were, respectively, CV 0.88 (width) and 2.33 (height), SD 0.22 (width) and 0.35 (height), minimum and maximum values 24.83-25.2 (width) and 14.56 - 15.75 (height). In the analysis of different images (similar) of an individual, greater discrepancies were observed in the values found. The cervical index, for example, presented minimum and maximum values of 15.38 and 37.5, a coefficient of variation of 0.29 and a standard deviation of 6.78. The SPGAP was shown to be a valid and reliable instrument for the quantitative analysis of body posture with applicability and

Análise comparativa entre avaliação postural visual e por fotogrametria computadorizada Comparative analysis between visual and computerized photogrammetry postural assessment

Directory of Open Access Journals (Sweden)

DH Iunes

2009-08-01

Full Text Available OBJETIVOS: Comparar a concordância interobservador da avaliação postural visual e por fotogrametria e verificar se os resultados quantitativos da fotogrametria correspondem à detecção de simetrias e assimetrias pela avaliação postural visual qualitativa. MÉTODOS: Vinte e um voluntários (24±1,9 anos foram inicialmente avaliados visualmente por três fisioterapeutas experientes que preencheram um protocolo de avaliação postural. Em seguida tiveram fotografados a face e o corpo todo nos planos frontal anterior, posterior e sagital. As fotos foram utilizadas para traçar ângulos a partir de marcadores fixados à pele, em vários pontos anatômicos, que são referências frequentes na avaliação postural tradicional. Essas fotografias foram analisadas por três examinadores diferentes da avaliação postural visual. A concordância de cada método de avaliação postural foi avaliada pelos Coeficientes de Cramer V ou de PHI, considerando-se um nível de significância de 5%. RESULTADOS: Foi encontrada uma concordância entre os examinadores que utilizaram a fotogrametria para todos os segmentos avaliados. Não apresentaram concordância os segmentos comissura labial (p=0,00, acrômio clavicular (p=0,01, esternoclavicular (p=0,00, espinhas ilíacas anterior e posterior (p=0,00 e p=0,01 e ângulo inferior da escápula (p=0,00, que foram analizados por meio da avaliação postural visual. A comparação entre a fotogrametria e a avaliação postural visual demonstrou que o grau de concordância entre os dois métodos de avaliação foi pouco significativo para alguns segmentos do membro inferior e pelve. CONCLUSÕES: Nessas condições experimentais, os dados da fotogrametria não podem ser correlacionados com os dados da avaliação postural visual. A avaliação postural visual apresentou dados menos concordantes do que a fotogrametria, devendo ser questionada sua utilização como gold-standart.OBJECTIVES: To compare the interobserver

Development of anticipatory postural adjustments during locomotion in children.

Science.gov (United States)

Hirschfeld, H; Forssberg, H

1992-08-01

1. Anticipatory postural adjustments were studied in children (6-14 yr of age) walking on a treadmill while pulling a handle. Electromyographs (EMGs) and movements were recorded from the left arm and leg. 2. Postural activity in the leg muscles preceded voluntary arm muscle activity in all age groups, including the youngest children (6 yr of age). The latency to both leg and arm muscle activity, from a triggering audio signal, decreased with age. 3. In older children the latency to both voluntary and postural activity was influenced by the phase of the step cycle. The shortest latency to the first activated postural muscle occurred during single support phase in combination with a long latency to arm muscle activity. 4. In the youngest children, there was no phase-dependent modulation of the latency to the activation of the postural muscles. The voluntary activity was delayed during the beginning of the support phase resulting in a long delay between leg and arm muscle activity. 5. The postural muscle activation pattern was modified in a phase-dependent manner in all children. Lateral gastrocnemius (LG) and hamstring muscles (HAM) were activated during the early support phase, whereas tibialis anterior (TA) and quadriceps (Q) muscles were activated during the late support phase and during the swing phase. However, in the 6-yr-old children, LG was also activated in the swing phase. LG was activated before the HAM activity in the youngest children but after HAM in 14-yr-old children and adults. 6. The occurrence of LG activity in postural responses before heel strike suggests an immature (nonplantigrade) gating of postural activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Use of Video Analysis System for Working Posture Evaluations

Science.gov (United States)

McKay, Timothy D.; Whitmore, Mihriban

1994-01-01

In a work environment, it is important to identify and quantify the relationship among work activities, working posture, and workplace design. Working posture may impact the physical comfort and well-being of individuals, as well as performance. The Posture Video Analysis Tool (PVAT) is an interactive menu and button driven software prototype written in Supercard (trademark). Human Factors analysts are provided with a predefined set of options typically associated with postural assessments and human performance issues. Once options have been selected, the program is used to evaluate working posture and dynamic tasks from video footage. PVAT has been used to evaluate postures from Orbiter missions, as well as from experimental testing of prototype glove box designs. PVAT can be used for video analysis in a number of industries, with little or no modification. It can contribute to various aspects of workplace design such as training, task allocations, procedural analyses, and hardware usability evaluations. The major advantage of the video analysis approach is the ability to gather data, non-intrusively, in restricted-access environments, such as emergency and operation rooms, contaminated areas, and control rooms. Video analysis also provides the opportunity to conduct preliminary evaluations of existing work areas.

Quantitative Postural Analysis of Children With Congenital Visual Impairment.

Science.gov (United States)

de Pádua, Michelle; Sauer, Juliana F; João, Silvia M A

2018-01-01

The aim of this study was to compare the postural alignment of children with visual impairment with that of children without visual impairment. The sample studied was 74 children of both sexes ages 5 to 12 years. Of these, 34 had visual impairment and 40 were control children. Digital photos from the standing position were used to analyze posture. Postural variables, such as tilt of the head, shoulder position, scapula position, lateral deviation of the spine, ankle position in the frontal plane and head posture, angle of thoracic kyphosis, angle of lumbar lordosis, pelvis position, and knee position in the frontal and sagittal planes, were measured with the Postural Assessment Software 0.63, version 36 (SAPO, São Paulo, Brazil), with markers placed in predetermined bony landmarks. The main results of this study showed that children with visual impairment have increased head tilt (P Visual impairment influences postural alignment. Children with visual impairment had increased head tilt, uneven shoulders, greater lateral deviation of the spine, thoracic kyphosis, lower lumbar lordosis, and more severe valgus deformities on knees. Copyright © 2017. Published by Elsevier Inc.

Effect of absence of vision on posture.

Science.gov (United States)

Alotaibi, Abdullah Z; Alghadir, Ahmad; Iqbal, Zaheen A; Anwer, Shahnawaz

2016-04-01

[Purpose] The visual system is one of the sensory systems that enables the body to assess and process information about the external environment. In the absence of vision, a blind person loses contact with the outside world and develops faulty motor patterns, which results in postural deficiencies. However, literature regarding the development of such deficiencies is limited. The aim of this study was to discuss the effect of absence of vision on posture, the possible biomechanics behind the resulting postural deficiencies, and strategies to correct and prevent them. [Subjects and Methods] Various electronic databases including PubMed, Medline, and Google scholar were examined using the words "body", "posture", "blind" and "absence of vision". References in the retrieved articles were also examined for cross-references. The search was limited to articles in the English language. [Results] A total of 74 papers were shortlisted for this review, most of which dated back to the 1950s and 60s. [Conclusion] Blind people exhibit consistent musculoskeletal deformities. Absence of vision leads to numerous abnormal sensory and motor interactions that often limit blind people in isolation. Rehabilitation of the blind is a multidisciplinary task. Specialists from different fields need to diagnose and treat the deficiencies of the blind together as a team. Before restoring the normal mechanics of posture and gait, the missing link with the external world should be reestablished.

Information content of pulmonary perfusion scintigraphy

International Nuclear Information System (INIS)

Kunieda, Takeyoshi

1982-01-01

A scinticamera computer system was used to measure the distribution of blood flow in both upright and supine lungs sequentially with the same counting geometry. The counting ratio of the upper half to the lower half lung, and the difference of distribution indices between supine lung and upright lung which is the fraction of postural change from the supine upper half to upright lower half lung to total distribution of blood flow, were referred to as ''U/L ratio'' and postural ''Change of Distribution'' respectively. U/L ratio correlated well with left atrial mean pressure (r = 0.87, p < 0.001) with the regression equation and Change of Distribution correlated well with pulmonary artery mean pressure (PAm) (r = -0.88, p < 0.001) in cardiac diseases. The relationship between the Change of Distribution and PAm was investigated using various regression analyses and the best fit was obtained by logarithmic regression (r = -0.92) with the regression equation. This regression equation means that there is no change of distribution of pulmonary blood flow with pulmonary artery pressure over 58 mmHg and that entire pulmonary blood flow comes to the lower half lung when the pulmonary artery pressure decreases to zero level. Pulmonary parenchymal and vascular disorders including primary pulmonary hypertension also held the same relationship with PAm. The relationship between upright U/L ratio and postural Change of Distribution permitted differentiation between precapillary pulmonary hypertension and postcapillary pulmonary hypertension. (J.P.N.)

Nonplantigrade Foot Posture: A Constraint on Dinosaur Body Size

OpenAIRE

Kubo, Tai; Kubo, Mugino O.

2016-01-01

Dinosaurs had functionally digitigrade or sub-unguligrade foot postures. With their immediate ancestors, dinosaurs were the only terrestrial nonplantigrades during the Mesozoic. Extant terrestrial mammals have different optimal body sizes according to their foot posture (plantigrade, digitigrade, and unguligrade), yet the relationship of nonplantigrade foot posture with dinosaur body size has never been investigated, even though the body size of dinosaurs has been studied intensively. Accordi...

A COMPARATIVE STUDY ON EFFECTIVENESS OF STATIC STRETCH AND HOLD RELAX TECHNIQUES OVER HAMSTRING FLEXIBILITY

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N. Vamsidhar

2014-12-01

Full Text Available Background: Flexibility is important in prevention of injury, muscular and postural imbalance more over the Hamstring flexibility has a lion share in sports performances and preventing DOMS. Stretching procedures increases the ROM by embarking on biomechanics and Neurologic and molecular mechanics. Hamstrings, the two joint muscle plays a crucial role in two joints integrity and also spine as they are in closed kinematic chain. The hamstring muscles represent the primary flexors of Knee. Hamstrings tightness results in Limits Knee extension when hip is flexed, Posterior Pelvic tilt, and flatten the lumbar spine. Methods: The subjects selected randomly and divided into two groups (Experimental group and control group.30 samples in One group applied with Static Stretch once a day for 3 repetitions 5 days a week for six weeks and 30 samples in other group applied with Hold relax technique once a day for 4 repetitions 5 days a week for six weeks. The knee joint range of motion was measured at the end of every week with Universal goniometer. Results: By comparing the means of Group – I, given Static Stretch and Group – II, given Hold relax Technique for six weeks implied that there is improvement of flexibility in Group – II and the ‘P’ value < 0.01 shows the difference is highly significant. Conclusion: This study concludes that the hold relax Technique method has proved to be better technique then the static stretch for improving hamstring flexibility.

Correcting Poor Posture without Awareness or Willpower

Science.gov (United States)

Wernik, Uri

2012-01-01

In this article, a new technique for correcting poor posture is presented. Rather than intentionally increasing awareness or mobilizing willpower to correct posture, this approach offers a game using randomly drawn cards with easy daily assignments. A case using the technique is presented to emphasize the subjective experience of living with poor…

Optimal Patient Positioning (Prone Versus Supine) for VMAT in Gynecologic Cancer: A Dosimetric Study on the Effect of Different Margins

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Heijkoop, Sabrina T., E-mail: s.heijkoop@erasmusmc.nl [Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam (Netherlands); Westerveld, Henrike; Bijker, Nina [Department of Radiation Oncology, Academic Medical Center, Amsterdam (Netherlands); Feije, Raphael; Sharfo, Abdul W. [Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam (Netherlands); Wieringen, Niek van [Department of Radiation Oncology, Academic Medical Center, Amsterdam (Netherlands); Mens, Jan Willem M. [Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam (Netherlands); Stalpers, Lukas J.A. [Department of Radiation Oncology, Academic Medical Center, Amsterdam (Netherlands); Hoogeman, Mischa S. [Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam (Netherlands)

2016-10-01

Purpose/Objective: It is unknown whether the historically found dosimetric advantages of treating gynecologic cancer with the patient in a prone position with use of a small-bowel displacement device (belly-board) remain when volumetric arc therapy (VMAT) is used and whether these advantages depend on the necessary margin between clinical target volume (CTV) and planning target volume (PTV). The aim of this study is to determine the best patient position (prone or supine) in terms of sparing organs at risk (OAR) for various CTV-to-PTV margins and VMAT dose delivery. Methods and Materials: In an institutional review board—approved study, 26 patients with gynecologic cancer scheduled for primary (9) or postoperative (17) radiation therapy were scanned in a prone position on a belly-board and in a supine position on the same day. The primary tumor CTV, nodal CTV, bladder, bowel, and rectum were delineated on both scans. The PTVs were created each with a different margin for the primary tumor and nodal CTV. The VMAT plans were generated with our in-house system for automated treatment planning. For all margin combinations, the supine and prone plans were compared with consideration of all OAR dose-volume parameters but with highest priority given to bowel cavity V{sub 45Gy} (cm{sup 3}). Results: For both groups, the prone position reduced the bowel cavity V{sub 45Gy}, in particular for nodal margins ≥10 mm (ΔV{sub 45Gy} = 23.9 ± 10.6 cm{sup 3}). However, for smaller margins, the advantage was much less pronounced (ΔV{sub 45Gy} = 6.5 ± 3.0 cm{sup 3}) and did not reach statistical significance. The rectum mean dose (D{sub mean}) was significantly lower (ΔD{sub mean} = 2.5 ± 0.3 Gy) in the prone position for both patient groups and for all margins, and the bladder D{sub mean} was significantly lower in the supine position (ΔD{sub mean} = 2.6 ± 0.4 Gy) only for the postoperative group. The advantage of the prone position was not present if it

Relaxation characteristics of hastelloy X

International Nuclear Information System (INIS)

Suzuki, Kazuhiko

1980-02-01

Relaxation diagrams of Hastelloy X (relaxation curves, relaxation design diagrams, etc.) were generated from the creep constitutive equation of Hastelloy X, using inelastic stress analysis code TEPICC-J. These data are in good agreement with experimental relaxation data of ORNL-5479. Three typical inelastic stress analyses were performed for various relaxation behaviors of the high-temperature structures. An attempt was also made to predict these relaxation behaviors by the relaxation curves. (author)

Combined hyperextension and supination of the elbow joint induces lateral ligament lesions. An experimental study of the pathoanatomy and kinematics in elbow ligament injuries

DEFF Research Database (Denmark)

Tyrdal, Stein; Olsen, Bo Sanderhoff

1998-01-01

An epidemiological study suggested that the injury mechanism of 'handball goalie's elbow' may be hyperextension. The pathomechanics of hyperextension combined with supination was studied in ten macroscopically normal, male, cadaveric elbow joint specimens. The age of the donors was 28.8 years...... rupture of the lateral collateral ligament. The lesions indicate that combined hyperextension and supination represent a possible mechanism leading to 'handball goalie's elbow'....

Effect of a single session of ear acupuncture on pain intensity and postural control in individuals with chronic low back pain: a randomized controlled trial

Directory of Open Access Journals (Sweden)

Andrea Ushinohama

2016-01-01

Full Text Available ABSTRACT Background Ear Acupuncture (EA is a form of acupuncture in which needles are applied to the external ear and has been used in multiple painful conditions. Low back pain (LBP is highly prevalent in active individuals and causes high economic burden to health systems worldwide. LBP affects the person’s ability to keep balance, especially in challenging conditions. Objective The aim of the study was to examine the effects of a single session of EA on pain intensity and body sway during postural tasks. Method Eighty adults with LBP and pain intensity equal to or greater than 4 (0-10 scale were randomly allocated (1:1 to EA group (EAG or placebo group (PG. Initially, the level of pain intensity was assessed. Next, participants stood still on a force plate either with feet in parallel or in semi-tandem and with eyes open or closed. Then, the EAG was treated with EA for 20 min and the PG was treated with detuned ultrasound. After the treatment, pain intensity was assessed again and the postural test was repeated. Pain intensity was the primary outcome and center of pressure sway area and speed were the secondary outcomes measured. Results Results revealed that pain intensity decreased in both groups after treatment, but decreased more in the EAG. For postural control, no effect of treatment and no interaction between treatment and postural condition on body sway were found. Conclusion Those findings indicate that EA is better than placebo to reduce pain, but neither treatment has any effect on postural control.

Standing orthostatic blood pressure measurements cannot be replaced by sitting measurements.

Science.gov (United States)

Breeuwsma, Anna C; Hartog, Laura C; Kamper, Adriaan M; Groenier, Klaas H; Bilo, Henk Jg; Kleefstra, Nanne; Van Hateren, Kornelis Jj

2017-08-01

As many elderly patients are not able to stand for several minutes, sitting orthostatic blood pressure (BP) measurements are sometimes used as an alternative. We aimed to investigate the difference in BP response and orthostatic hypotension (OH) prevalence between the standard postural change to the sitting and the standing position in a cross-sectional observational study. BP was measured with a continuous BP measurement device during two postural changes, from supine to the sitting and from supine to the standing position. Linear mixed models were used to investigate the differences in changes (Δ) of systolic BP (SBP) and diastolic BP (DBP) between the two postural changes. The prevalence and the positive and negative proportions of agreement of OH were calculated of the two postural changes. One hundred and four patients with a mean age of 69 years were included. ΔSBP was significantly larger in the standing position compared with the sitting between 0 and 44 s. ΔDBP was significantly larger in the sitting position compared with the standing 75-224 s after postural change. The prevalence of OH was 66.3% (95% confidence interval (CI) 57.2, 75.4) in the standing position and 67.3% (95% CI 58.3, 76.3) in the sitting position. The positive proportion of agreement was 74.8% and the negative proportion of agreement was 49.3%. A clear difference was seen in BP response between the two postural changes. Although no significant difference in prevalence of OH was observed, the positive and negative proportion of agreement of the prevalence of OH were poor to moderate, which indicates a different outcome between both postural changes.