Conservative treatment of a patient with previously unresponsive whiplash-associated disorders using clinical biomechanics of posture rehabilitation methods.

PubMed

Ferrantelli, Joseph R; Harrison, Deed E; Harrison, Donald D; Stewart, Denis

2005-01-01

To describe the treatment of a patient with chronic whiplash-associated disorders (WADs) previously unresponsive to multiple physical therapy and chiropractic treatments, which resolved following Clinical Biomechanics of Posture (CBP) rehabilitation methods. A 40-year-old man involved in a high-speed rear-impact collision developed chronic WADs including cervicothoracic, shoulder, and arm pain and headache. The patient was diagnosed with a confirmed chip fracture of the C5 vertebra and cervical and thoracic disk herniations. He was treated with traditional chiropractic and physical therapy modalities but experienced only temporary symptomatic reduction and was later given a whole body permanent impairment rating of 33% by an orthopedic surgeon. The patient was treated with CBP mirror-image cervical spine adjustments, exercise, and traction to reduce forward head posture and cervical kyphosis. A presentation of abnormal head protrusion resolved and cervical kyphosis returned to lordosis posttreatment. His initial neck disability index was 46% and 0% at the end of care. Verbal pain rating scales also improved for neck pain (from 5/10 to 0/10). A patient with chronic WADs and abnormal head protrusion, cervical kyphosis, and disk herniation experienced an improvement in symptoms and function after the use of CBP rehabilitation protocols when other traditional chiropractic and physical therapy procedures showed little or no lasting improvement.

Dorsal midbrain syndrome associated with persistent neck extension: Clinical and diagnostic imaging findings in 2 dogs

PubMed Central

Canal, Sara; Baroni, Massimo; Falzone, Cristian; De Benedictis, Giulia M.; Bernardini, Marco

2015-01-01

Two young dogs were evaluated for an acute onset of abnormal head posture and eye movement. Neurological examination was characterized mostly by permanent neck extension, abnormalities of pupils, and eye movement. A mesencephalic mass lesion was detected on magnetic resonance imaging in both cases. Neurophysiological pathways likely responsible for this peculiar clinical presentation are discussed. PMID:26663922

Kinematics of the human mandible for different head postures.

PubMed

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 Efficacy of Bilateral Lateral Rectus Recession According to Secondary Deviation Measurements in Unilateral Exotropic Duane Retraction Syndrome.

PubMed

Mezad-Koursh, Daphna; Leshno, Ari; Klein, Ainat; Stolovich, Chaim

2018-01-01

To evaluate the surgical results of asymmetric bilateral lateral rectus recession in exotropic Duane retraction syndrome with abnormal face turn toward the opposite side according to secondary deviation measurements. Retrospective chart review. Seven cases of unilateral exotropic Duane retraction syndrome were reviewed. All cases had globe retraction on adduction and exotropia with limited adduction, five of which also had mild limitation of abduction. Four cases had upshoot/downshoot on adduction and all patients had face turn. Exotropia was measured in forced primary position. The average lateral rectus recession was 6.36 mm (range: 5.5 to 7.5 mm) in the affected eye and 7.36 mm (range: 6.5 to 8.5 mm) in the healthy eye. The mean follow-up period was 282 days. Mean exotropia in the forced primary position improved from 27.9 ± 5.7 prism diopters (PD) preoperatively to 7.9 ± 16.8 PD postoperatively (P = .025). Head position resolved completely in all but one case (P =.031). There were no significant changes in ductions. The results suggest that asymmetric bilateral lateral rectus recession in exotropic Duane retraction syndrome with abnormal head turn posture successfully eliminates abnormal head turn posture and exotropia in most cases. [J Pediatr Ophthalmol Strabismus. 2018;55(1):47-52.]. Copyright 2017, SLACK Incorporated.

The effect of a single massage based on the tensegrity principle on postural stability in young women.

PubMed

Cieślik, Błażej; Podsiadły, Ireneusz; Kuczyński, Michał; Ostrowska, Bożena

2017-11-06

The aim of this study was to investigate the effects of normalized muscle tension via tensegrity-based massage on postural stability in a sample of female young adults. Nineteen females aged 21.8 ± 1.9 years were recruited presenting abnormal tension at muscles adhering to any of the following structural sites: superior iliac spine, lateral sacropelvic surface, linea aspera at 1/2 of femur length, and superior nuchal line of the occiput. Balance and postural control were assessed during bipedal stance using a force platform in multiple conditions: hard surface or soft foam surface with the head in either a neutral posture or tilted backward. Baseline and 3-min and 15-min post-treatment measures were collected while barefoot and eyes closed. Main outcomes measures included center of pressure variability, range, radius, and velocity in the anteroposterior (AP) mediolateral (ML) dimensions. In the solid surface with neutral head posture condition only AP COP measures decreased significantly (p< 0.05). In the soft surface condition, significant differences were observed in the AP and ML dimensions among most measures (p< 0.05). A single application of tensegrity-based massage positively influenced postural control in young adult females, particularly in the AP direction.

Management of Duane retraction syndrome with prismatic glasses

PubMed Central

Aygit, Ebru Demet; Kocamaz, Murat; Inal, Asli; Fazil, Korhan; Ocak, Osman Bulut; Akar, Serpil; Gokyigit, Birsen

2017-01-01

Purpose To report the results of using prismatic glasses for Duane retraction syndrome (DRS). Methods Data were obtained from the records of patients who were evaluated during the year 2000 in the Strabismus Unit of the Beyoglu Eye Training and Research Hospital. The average follow-up was 12.2±17.7 months. In all cases, 2 main variables were evaluated: horizontal deviation in the primary position and face turn. Prismatic glasses were provided to patients according to the degree of shift in the primary position. Results The mean age of patients was 11.2 years. An analysis was performed on the data collected from 12 cases; 7 patients were females (58.3%) and 5 were males (41.7%), with 11 (91.7%) cases being of type I DRS. All 12 patients had abnormal head posture (face turn) and an angle of mean deviation equaling 10 PD (prism dioptri). Conclusion Treatment was individualized on a case-by-case basis. Prismatic glasses are useful for eliminating abnormal head posture and ocular misalignment in selected cases. PMID:28442887

Postural disorders in mouth breathing children: a systematic review.

PubMed

Neiva, Patricia Dayrell; Kirkwood, Renata Noce; Mendes, Polyana Leite; Zabjek, Karl; Becker, Helena Gonçalves; Mathur, Sunita

Mouth breathing syndrome can cause sleep disturbances that compromise the performance of children in school. It might also cause postural abnormalities involving the head and cervical spine; however, the association between postural abnormalities and mouth breathing in children is unclear. To assess the methodological quality of studies and determine if there is an association between mouth breathing and postural disorders in children. Databases comprised MEDLINE, CINAHL, PEDro, LILACS, EMBASE and Cochrane Central Registrar of Controlled Trials. Searches were until March 2016 and included studies that evaluated postural disorders in children diagnosed with mouth breathing. The Downs and Black checklist was used to evaluate the quality of the evidences. Ten studies were included totaling 417 children from 5 to 14 years. Two studies used the New York State Postural Rating Scale, seven used photography and one used motion capture to measure posture. The methods used to analyze the data included the Postural Analysis Software (SAPO), Fisiometer, ALCimagem and routines in MATLAB program. Quality assessment resulted in low scores (<14) for all the studies. The main areas of weakness were a clear description of the participants, of the methods used to access posture, of the principal confounders and lack of power analysis. External and internal validity were also threatened by the lack of a representative sample and blinding of the participants and assessors, respectively. The review provides low evidence that mouth-breathing pattern in children between the ages 5-14 years is associated with postural deviations. Copyright © 2017 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier Editora Ltda. All rights reserved.

[Stereovideographic evaluation of the postural geometry of healthy and scoliotic patients].

PubMed

De la Huerta, F; Leroux, M A; Zabjek, K F; Coillard, C; Rivard, C H

1998-01-01

Idiopathic scoliosis principally characterised by a deformation of the vertebral column can also be associated to postural abnormalities. The validity and reliability of current quantitative postural evaluations has not been thoroughly documented, frequently limited by a two dimensional view of the patient, and do not include the whole posture of the patient. The purpose of this study is to 1) quantify within and between-session reliability of a stereovideographic Postural Geometry (PG) evaluation and 2) to investigate the sensitivity of this technique for the postural evaluation of scoliosis patients. The PG of 14 control subjects and 9 untreated scoliosis patients were evaluated with 5 repeat trials, on two occasions. Postural geometry parameters that describe the position and orientation of the pelvis, trunk, scapular girdle and head were calculated based on the 3-dimensional co-ordinates of anatomical landmarks. The mean between and within-session variability across all parameters were 12.5 mm, 2.8 degrees and 5.4 mm and 1.4 degrees respectively. The patient group was heterogeneous with some noted pathological characteristics. This global stereovideographic postural geometry evaluation appears to demonstrate sufficient reliability and sensitivity to follow-up on the posture of scoliosis patients.

Effects of Head Rotation and Head Tilt on Pharyngeal Pressure Events Using High Resolution Manometry.

PubMed

Kim, Cheol Ki; Ryu, Ju Seok; Song, Sun Hong; Koo, Jung Hoi; Lee, Kyung Duck; Park, Hee Sun; Oh, Yoongul; Min, Kyunghoon

2015-06-01

To observe changes in pharyngeal pressure during the swallowing process according to postures in normal individuals using high-resolution manometry (HRM). Ten healthy volunteers drank 5 mL of water twice while sitting in a neutral posture. Thereafter, they drank the same amount of water twice in the head rotation and head tilting postures. The pressure and time during the deglutition process for each posture were measured with HRM. The data obtained for these two postures were compared with those obtained from the neutral posture. The maximum pressure, area, rise time, and duration in velopharynx (VP) and tongue base (TB) were not affected by changes in posture. In comparison, the maximum pressure and the pre-upper esophageal sphincter (UES) maximum pressure of the lower pharynx in the counter-catheter head rotation posture were lower than those in the neutral posture. The lower pharynx pressure in the catheter head tilting posture was higher than that in the counter-catheter head tilting. The changes in the VP peak and epiglottis, VP and TB peaks, and the VP onset and post-UES time intervals were significant in head tilting and head rotation toward the catheter postures, as compared with neutral posture. The pharyngeal pressure and time parameter analysis using HRM determined the availability of head rotation as a compensatory technique for safe swallowing. Tilting the head smoothes the progress of food by increasing the pressure in the pharynx.

Effects of Head Rotation and Head Tilt on Pharyngeal Pressure Events Using High Resolution Manometry

PubMed Central

Kim, Cheol Ki; Song, Sun Hong; Koo, Jung Hoi; Lee, Kyung Duck; Park, Hee Sun; Oh, Yoongul; Min, Kyunghoon

2015-01-01

Objective To observe changes in pharyngeal pressure during the swallowing process according to postures in normal individuals using high-resolution manometry (HRM). Methods Ten healthy volunteers drank 5 mL of water twice while sitting in a neutral posture. Thereafter, they drank the same amount of water twice in the head rotation and head tilting postures. The pressure and time during the deglutition process for each posture were measured with HRM. The data obtained for these two postures were compared with those obtained from the neutral posture. Results The maximum pressure, area, rise time, and duration in velopharynx (VP) and tongue base (TB) were not affected by changes in posture. In comparison, the maximum pressure and the pre-upper esophageal sphincter (UES) maximum pressure of the lower pharynx in the counter-catheter head rotation posture were lower than those in the neutral posture. The lower pharynx pressure in the catheter head tilting posture was higher than that in the counter-catheter head tilting. The changes in the VP peak and epiglottis, VP and TB peaks, and the VP onset and post-UES time intervals were significant in head tilting and head rotation toward the catheter postures, as compared with neutral posture. Conclusion The pharyngeal pressure and time parameter analysis using HRM determined the availability of head rotation as a compensatory technique for safe swallowing. Tilting the head smoothes the progress of food by increasing the pressure in the pharynx. PMID:26161349

Infantile aperiodic alternating nystagmus.

PubMed

Hertle, Richard W; Reznick, Leah; Yang, Dongsheng

2009-01-01

This study identifies the clinical and ocular motility characteristics of the periodic and aperiodic forms of infantile alternating nystagmus (IAPAN) and establishes the range of electrophysiological and clinical characteristics while providing clues to its presence and pathophysiology. Seventy-eight patients with ocular oscillations consistent with IAPAN were reported. Outcome variables were: age, follow-up in months, vision, strabismus, other eye and systemic abnormalities, head position, periodicity, cycle and null period duration, foveation time, waveforms, and cycle symmetry. Age range was 1 to 67 years, 50% had pure periodic and aperiodic forms, 46% had albinism, 26% had binocular acuity of 20/40 or greater, 72% had strabismus, 35% had amblyopia, 31% had other eye disease, 14% had systemic disease, 87% had an anomalous head posture, and 65% had binocular directional asymmetry. The periodic cycle averaged 224 seconds and the aperiodic cycle ranged from 2 to more than 300 seconds. One in three patients with strabismus and nystagmus periodicity had a static head posture. Fifteen percent of the infantile nystagmus syndrome population had either the periodic or aperiodic form. A changing null period is often clinically missed because of long or irregular cycles, decreased acuity, associated strabismus, and either a nonexistent or inconsistent head posture. The changing null period is easier to recognize using eye movement recordings or if the non-preferred eye is occluded and the preferred eye is examined with the head straight and gaze in primary position for at least 5 to 7 minutes. The recognition of this variant has profound treatment implications.

Effect of different head-neck-jaw postures on cervicocephalic kinesthetic sense.

PubMed

Zafar, H; Alghadir, A H; Iqbal, Z A

2017-12-01

To investigate the effect of different induced head-neck-jaw postures on head-neck relocation error among healthy subjects. 30 healthy adult male subjects participated in this study. Cervicocephalic kinesthetic sense was measured while standing, habitual sitting, habitual sitting with clenched jaw and habitual sitting with forward head posture during right rotation, left rotation, flexion and extension using kinesthetic sensibility test. Head-neck relocation error was least while standing, followed by habitual sitting, habitual sitting with forward head posture and habitual sitting with jaw clenched. However, there was no significant difference in error between different tested postures during all the movements. To the best of our knowledge, this is the first study to see the effect of different induced head-neck-jaw postures on head-neck position sense among healthy subjects. Assuming a posture for a short duration of time doesn't affect head-neck relocation error in normal healthy subjects.

The internal representation of head orientation differs for conscious perception and balance control.

PubMed

Dalton, Brian H; Rasman, Brandon G; Inglis, J Timothy; Blouin, Jean-Sébastien

2017-04-15

We tested perceived head-on-feet orientation and the direction of vestibular-evoked balance responses in passively and actively held head-turned postures. The direction of vestibular-evoked balance responses was not aligned with perceived head-on-feet orientation while maintaining prolonged passively held head-turned postures. Furthermore, static visual cues of head-on-feet orientation did not update the estimate of head posture for the balance controller. A prolonged actively held head-turned posture did not elicit a rotation in the direction of the vestibular-evoked balance response despite a significant rotation in perceived angular head posture. It is proposed that conscious perception of head posture and the transformation of vestibular signals for standing balance relying on this head posture are not dependent on the same internal representation. Rather, the balance system may operate under its own sensorimotor principles, which are partly independent from perception. Vestibular signals used for balance control must be integrated with other sensorimotor cues to allow transformation of descending signals according to an internal representation of body configuration. We explored two alternative models of sensorimotor integration that propose (1) a single internal representation of head-on-feet orientation is responsible for perceived postural orientation and standing balance or (2) conscious perception and balance control are driven by separate internal representations. During three experiments, participants stood quietly while passively or actively maintaining a prolonged head-turned posture (>10 min). Throughout the trials, participants intermittently reported their perceived head angular position, and subsequently electrical vestibular stimuli were delivered to elicit whole-body balance responses. Visual recalibration of head-on-feet posture was used to determine whether static visual cues are used to update the internal representation of body configuration for perceived orientation and standing balance. All three experiments involved situations in which the vestibular-evoked balance response was not orthogonal to perceived head-on-feet orientation, regardless of the visual information provided. For prolonged head-turned postures, balance responses consistent with actual head-on-feet posture occurred only during the active condition. Our results indicate that conscious perception of head-on-feet posture and vestibular control of balance do not rely on the same internal representation, but instead treat sensorimotor cues in parallel and may arrive at different conclusions regarding head-on-feet posture. The balance system appears to bypass static visual cues of postural orientation and mainly use other sensorimotor signals of head-on-feet position to transform vestibular signals of head motion, a mechanism appropriate for most daily activities. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

Effect of different head-neck-jaw postures on cervicocephalic kinesthetic sense

PubMed Central

Zafar, Hamayun; Alghadir, Ahmad H.; Iqbal, Zaheen A.

2017-01-01

Objectives: To investigate the effect of different induced head-neck-jaw postures on head-neck relocation error among healthy subjects. Methods: 30 healthy adult male subjects participated in this study. Cervicocephalic kinesthetic sense was measured while standing, habitual sitting, habitual sitting with clenched jaw and habitual sitting with forward head posture during right rotation, left rotation, flexion and extension using kinesthetic sensibility test. Results: Head-neck relocation error was least while standing, followed by habitual sitting, habitual sitting with forward head posture and habitual sitting with jaw clenched. However, there was no significant difference in error between different tested postures during all the movements. Conclusions: To the best of our knowledge, this is the first study to see the effect of different induced head-neck-jaw postures on head-neck position sense among healthy subjects. Assuming a posture for a short duration of time doesn’t affect head-neck relocation error in normal healthy subjects. PMID:29199196

Effect of posture on oxygenation and respiratory muscle strength in convalescent infants

PubMed Central

Dimitriou, G; Greenough, A; Pink, L; McGhee, A; Hickey, A; Rafferty, G

2002-01-01

Objective: To determine if differences in respiratory muscle strength could explain any posture related effects on oxygenation in convalescent neonates. Methods: Infants were examined in three postures: supine, supine with head up tilt of 45°, and prone. A subsequent study was performed to determine the influence of head position in the supine posture. In each posture/head position, oxygen saturation (SaO2) was determined and respiratory muscle strength assessed by measurement of the maximum inspiratory pressure (PIMAX). Patients: Twenty infants, median gestational age 34.5 weeks (range 25–43), and 10 infants, median gestational age 33 weeks (range 30–36), were entered into the first and second study respectively. Results: Oxygenation was higher in the prone and supine with 45° head up tilt postures than in the supine posture (p<0.001), whereas PIMAX was higher in the supine and supine with head up tilt of 45° postures than in the prone posture (p<0.001). Head position did not influence the effect of posture on PIMAX or oxygenation. Conclusion: Superior oxygenation in the prone posture in convalescent infants was not explained by greater respiratory muscle strength, as this was superior in the supine posture. PMID:11978742

Application of Infrared Thermal Imaging in a Violinist with Temporomandibular Disorder.

PubMed

Clemente, M; Coimbra, D; Silva, A; Aguiar Branco, C; Pinho, J C

2015-12-01

Temporomandibular disorders (TMD) consist of a group of pathologies that affect the masticatory muscles, temporomandibular joints (TMJ), and/or related structures. String instrumentalists, like many orchestra musicians, can spend hours with head postures that may influence the biomechanical behavior of the TMJ and the muscles of the craniocervicomandibular complex (CCMC). The adoption of abnormal postures acquired during performance by musicians can lead to muscular hyperactivity of the head and cervical muscles, with the possible appearance of TMD. Medical infrared thermography is a non-invasive procedure that can monitor the changes in the superficial tissue related to blood circulation and may serve as a complement to the clinical examination. The objective of this study was to use infrared thermography to evaluate, in one subject, the cutaneous thermal changes adjacent to the CCMC that occur before, during, and after playing a string instrument.

Photographic measurement of head and cervical posture when viewing mobile phone: a pilot study.

PubMed

Guan, Xiaofei; Fan, Guoxin; Wu, Xinbo; Zeng, Ying; Su, Hang; Gu, Guangfei; Zhou, Qi; Gu, Xin; Zhang, Hailong; He, Shisheng

2015-12-01

With the dramatic growth of mobile phone usage, concerns have been raised with regard to the adverse health effects of mobile phone on spinal posture. The aim of this study was to determine the head and cervical postures by photogrammetry when viewing the mobile phone screen, compared with those in neutral standing posture. A total of 186 subjects (81 females and 105 males) aged from 17 to 31 years old participated in this study. Subjects were instructed to stand neutrally and using mobile phone as in daily life. Using a photographic method, the sagittal head and cervical postures were assessed by head tilt angle, neck tilt angle, forward head shift and gaze angle. The photographic method showed a high intra-rater and inter-rater reliability in measuring the sagittal posture of cervical spine and gaze angle (ICCs ranged from 0.80 to 0.99). When looking at mobile phone, the head tilt angle significantly increased (from 74.55° to 95.22°, p = 0.000) and the neck angle decreased (from 54.68° to 38.77°, p = 0.000). The forward head posture was also confirmed by the significantly increased head shift (from 10.90 to 13.85 cm, p = 0.000). The posture assumed in mobile phone use was significantly correlated with neutral posture (p < 0.05). Males displayed a more forward head posture than females (p < 0.05). The head tilt angle was positively correlated with the gaze angle (r = 0.616, p = 0.000), while the neck tilt angle was negatively correlated with the gaze angle (r = -0.628, p = 0.000). Photogrammetry is a reliable, quantitative method to evaluate the head and cervical posture during mobile phone use. Compared to neutral standing, subjects display a more forward head posture when viewing the mobile phone screen, which is correlated with neutral posture, gaze angle and gender. Future studies will be needed to investigate a dose-response relationship between mobile phone use and assumed posture.

Upper body kinematics in patients with cerebellar ataxia.

PubMed

Conte, Carmela; Pierelli, Francesco; Casali, Carlo; Ranavolo, Alberto; Draicchio, Francesco; Martino, Giovanni; Harfoush, Mahmoud; Padua, Luca; Coppola, Gianluca; Sandrini, Giorgio; Serrao, Mariano

2014-12-01

Although abnormal oscillations of the trunk are a common clinical feature in patients with cerebellar ataxia, the kinematic behaviour of the upper body in ataxic patients has yet to be investigated in quantitative studies. In this study, an optoelectronic motion analysis system was used to measure the ranges of motion (ROMs) of the head and trunk segments in the sagittal, frontal and yaw planes in 16 patients with degenerative cerebellar ataxia during gait at self-selected speed. The data obtained were compared with those collected in a gender-, age- and gait speed-matched sample of healthy subjects and correlated with gait variables (time-distance means and coefficients of variation) and clinical variables (disease onset, duration and severity). The results showed significantly larger head and/or trunk ROMs in ataxic patients compared with controls in all three spatial planes, and significant correlations between trunk ROMs and disease duration and severity (in sagittal and frontal planes) and time-distance parameters (in the yaw plane), and between both head and trunk ROMs and swing phase duration variability (in the sagittal plane). Furthermore, the ataxic patients showed a flexed posture of both the head and the trunk during walking. In conclusion, our study revealed abnormal motor behaviour of the upper body in ataxic patients, mainly resulting in a flexed posture and larger oscillations of the head and trunk. The results of the correlation analyses suggest that the longer and more severe the disease, the larger the upper body oscillations and that large trunk oscillations may explain some aspects of gait variability. These results suggest the need of specific rehabilitation treatments or the use of elastic orthoses that may be particularly useful to reduce trunk oscillations and improve dynamic stability.

[Correlation analysis between position of head, cervical curvature classification and balance of cervical spine through lateral plain radiograph measurement].

PubMed

Wang, Kuan; Deng, Zhen; Wang, Hui-Hao; Li, Zheng-Yan; Niu, Wen-Xin; Chen, Bo; Zhang, Ming-Cai; Yuan, Wei-An; Zhan, Hong-Sheng

2017-05-25

To analyze the relationship between position of head, cervical curvature type and associated cervical balance parameters in a neutral looking-forward posture. Cervical lateral X-rays of 60 patients with cervical spondylosis were selected from January to December 2015. There were 22 males and 38 females with an average age of (35.5±10.9) years old. The measured parameters included cervical curvature type, McGregor slope, C2 lower end plate slope, T1 slope, center of gravity to C7 sagittal vertical offset (CG-C7 SVA), and C2 to C7 sagittal vertical offset (C2-C7 SVA). The parameters were analyzed using Spearman correlation. The cervical curvature type was significantly correlated with C2 lower endplate slope, C0-C2 angle (total degree of C2 lower endplate slope plus McGregor slope), CG-C7 SVA and T1 slope ( P <0.05), but it was not significantly correlated McGregor slope ( P >0.05). C2 lower endplate slope and C2-C7 SVA (r=0.87) were significantly ( P <0.05) correlated with CG-C7 SVA ( P <0.05). There was certain some relationship among position of head, cervical curvature type and associated cervical balance parameters in a neutral looking-forward posture. The center of gravity of the head would backwards shift following faced upward. A position of extension with posterior-shifting of the head would suggest that it may be accompanied with a relatively normal lordosis of the cervical spine. Some patients with abnormal curvature showed slightly bended head in the natural posture. Health education toward these people would be meaningful to restore the balance of their neck.

Thermoregulatory postures limit antipredator responses in peafowl

PubMed Central

Lam, Jennifer; Schultz, Rachel; Davis, Melissa

2018-01-01

ABSTRACT 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. PMID:29305466

Thermoregulatory postures limit antipredator responses in peafowl.

PubMed

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.

The envelope of motion of the cervical spine and its influence on the maximum torque generating capability of the neck muscles.

PubMed

Siegler, Sorin; Caravaggi, Paolo; Tangorra, James; Milone, Mary; Namani, Ramya; Marchetto, Paul A

2015-10-15

The posture of the head and neck is critical for predicting and assessing the risk of injury during high accelerations, such as those arising during motor accidents or in collision sports. Current knowledge suggests that the head's range-of-motion (ROM) and the torque-generating capability of neck muscles are both dependent and affected by head posture. A deeper understanding of the relationship between head posture, ROM and maximum torque-generating capability of neck muscles may help assess the risk of injury and develop means to reduce such risks. The aim of this study was to use a previously-validated device, known as Neck Flexibility Tester, to quantify the effects of head's posture on the available ROM and torque-generating capability of neck muscles. Ten young asymptomatic volunteers were enrolled in the study. The tri-axial orientation of the subjects' head was controlled via the Neck Flexibility Tester device. The head ROM was measured for each flexed, extended, axially rotated, and laterally bent head's orientation and compared to that in unconstrained neutral posture. Similarly, the torque applied about the three anatomical axes during Isometric Maximum Voluntary Contraction (IMVC) of the neck muscles was measured in six head's postures and compared to that in fully-constrained neutral posture. The further from neutral the neck posture was the larger the decrease in ROM and IMVC. Head extension and combined two-plane rotations postures, such as extension with lateral bending, produced the largest decreases in ROM and IMVC, thus suggesting that these postures pose the highest potential risk for injury. Copyright © 2015 Elsevier Ltd. All rights reserved.

Head posture measurements among work vehicle drivers and implications for work and workplace design.

PubMed

Eklund, J; Odenrick, P; Zettergren, S; Johansson, H

1994-04-01

An increased risk of musculoskeletal disorders, e.g. from the neck region, has been found among professional drivers of work vehicles. The purpose of this study was to identify causes of postural load and implications for vehicle design and work tasks. A second purpose was to develop the methods for measurement and analysis of head postures. Field measurements of head postures for drivers of fork lift trucks, forestry machines, and cranes were carried out. The equipment used was an electric goniometer measurement system, containing a mechanical transmission between the head and the upper trunk. Methods for data presentation and quantification were developed. The results showed that rotatable and movable driver cabins improved head postures and viewing angles substantially. Narrow window frame structures and large, optimally-placed windows were also advantageous. The steering wheel, controls, and a high backrest restricted shoulder rotation, which increased head rotation in unfavourable viewing angles. Improved workspace layouts and work organization factors such as job enlargement decreased the influence of strenuous postures. The results also showed that head postures should be analysed in two or three dimensions simultaneously, otherwise the postures taken will be underestimated in relation to the maximal voluntary movement.

Pathology and the posture of the La Chapelle-aux-Saints Neandertal.

PubMed

Trinkaus, E

1985-05-01

The depiction of the Neandertals as incompletely erect was based primarily on Boule's (1911, 1912a, 1913) analysis of the La Chapelle-aux-Saints 1 partial skeleton. The inaccurate aspects of Boule's postural reconstruction were corrected during the 1950s. However, it has come to be believed, following Straus and Cave (1957), that Boule's errors of reconstruction were due to the diseased condition of the La Chapelle-aux-Saints 1 remains, rather than to Boule's misinterpretation of morphology. The abnormalities on the La Chapelle-aux-Saints 1 postcranium include: lower cervical, upper thoracic, and lower thoracic intervertebral degenerative joint disease (DJD), a distal fracture of a mid-thoracic rib, extensive DJD of the left hip, DJD of the right fifth proximal interphalangeal articulation, bilateral humeral head eburnation, and minor exostosis formation on the right humerus, ulna, and radius. These were associated with extensive alveolar inflammation including apical abscesses and antemortem tooth loss, some temporomandibular DJD, bilateral auditory exostoses, and minimal occipital condyle DJD. None of these abnormalities significantly affected Boule's Neandertal postural reconstruction, and a review of his analysis indicates that early twentieth century interpretations of skeletal morphology (primarily of the cranium, cervical vertebrae, lumbar and sacral vertebrae, proximal femora and tibiae, posterior tarsals, and hallucial tarsometatarsal joint), combined with Boule's evolutionary preconceptions, were responsible for his mistaken view of Neandertal posture.

Forward head posture: its structural and functional influence on the stomatognathic system, a conceptual study.

PubMed

Gonzalez, H E; Manns, A

1996-01-01

An extensive conceptual analysis to establish the primary role a forward head posture plays in the appearance of some craniomandibular dysfunctions and internal derangements of the temporomandibular joints, associated to craniocervical postural disturbances. The analysis is based on findings contributed by scientific investigations in the field of dentofacial orthopedics and dysfunction. Special emphasis has been put on the influence of forward head posture on the craniofacial growth as it can determine a morphoskeletal and neuromuscular pattern leading to a dysfunctional condition. A correlation is established between Class II Occlusion, forward head posture, and craniomandibular dysfunction. The concept of craniocervical postural position is defined, as well as its close relation to the mandibular postural position.

Rest tremor in idiopathic adult-onset dystonia.

PubMed

Gigante, A F; Berardelli, A; Defazio, G

2016-05-01

Tremor in dystonia has been described as a postural or kinetic abnormality. In recent series, however, patients with idiopathic adult-onset dystonia also displayed rest tremor. The frequency and distribution of rest tremor were studied in a cohort of 173 consecutive Italian patients affected by various forms of idiopathic adult-onset dystonia attending our movement disorder clinic over 8 months. Examination revealed tremor in 59/173 patients (34%): 12 patients had head tremor, 34 patients had arm tremor, whilst 13 patients presented tremor in both sites. Head tremor was postural in all patients, whereas arm tremor was postural/kinetic in 28 patients, only at rest in one and both postural/kinetic and at rest in 18 patients. Patients with tremor were more likely to have segmental/multifocal dystonia. Patients who had rest tremor (either alone or associated with action tremor) had a higher age at dystonia onset and a greater frequency of dystonic arm involvement than patients with action tremor alone or without tremor. Both action and rest tremor are part of the tremor spectrum of adult-onset dystonia and are more frequently encountered in segmental/multifocal dystonia. The higher age at dystonia onset and the greater frequency of arm dystonia in patients with rest tremor may have pathophysiological implications and may account, at least in part, for the previous lack of identification of rest tremor as one possible type of tremor present in dystonia. © 2016 EAN.

Is there a relationship between head posture and craniomandibular pain?

PubMed

Visscher, C M; De Boer, W; Lobbezoo, F; Habets, L L M H; Naeije, M

2002-11-01

An often-suggested factor in the aetiology of craniomandibular disorders (CMD) is an anteroposition of the head. However, the results of clinical studies to the relationship between CMD and head posture are contradictory. Therefore, the first aim of this study was to determine differences in head posture between well-defined CMD pain patients with or without a painful cervical spine disorder and healthy controls. The second aim was to determine differences in head posture between myogenous and arthrogenous CMD pain patients and controls. Two hundred and fifty persons entered the study. From each person, a standardized oral history was taken and blind physical examinations of the masticatory system and of the neck were performed. The participants were only included into one of the subgroups when the presence or absence of their symptoms was confirmed by the results of the physical examination. Head posture was quantified using lateral photographs and a lateral radiograph of the head and the cervical spine. After correction for age and gender effects, no difference in head posture was found between any of the patient and non-patient groups (P > 0.27). Therefore, this study does not support the suggestion that painful craniomandibular disorders, with or without a painful cervical spine disorder, are related to head posture.

Does head posture have a significant effect on the hyoid bone position and sternocleidomastoid electromyographic activity in young adults?

PubMed

Valenzuela, Saúl; Miralles, Rodolfo; Ravera, María José; Zúñiga, Claudia; Santander, Hugo; Ferrer, Marcelo; Nakouzi, Jorge

2005-07-01

The aim of this study was to evaluate the associations between head posture (head extension, normal head posture, and head flexion) and anteroposterior head position, hyoid bone position, and the sternocleidomastoid integrated electromyographic (IEMG) activity in a sample of young adults. The study included 50 individuals with natural dentition and bilateral molar support. A lateral craniocervical radiograph was taken for each subject and a cephalometric analysis was performed. Head posture was measured by means of the craniovertebral angle formed by the MacGregor plane and the odontoid plane. According to the value of this angle, the sample was divided into the following three groups: head extension (less than 95 degrees); normal head posture (between 95 degrees and 106 degrees); and head flexion (more than 106 degrees). The following cephalometric measurements were taken to compare the three groups: anteroposterior head position (true vertical plane/pterygoid distance), anteroposterior hyoid bone position (true vertical plane-Ha distance), vertical hyoid bone position (H-H' distance in the hyoid triangle), and CO-C2 distance. In the three groups, IEMG recordings at rest and during swallowing of saliva and maximal voluntary clenching were performed by placing bipolar surface electrodes on the right and left sternocleidomastoid muscles. In addition, the condition with/without craniomandibular dysfunction (CMD) in each group was also assessed. Head posture showed no significant association with anteroposterior head position, anteroposterior hyoid bone position, vertical hyoid bone position, or sternocleidomastoid IEMG activity. There was no association to head posture with/without the condition of CMD. Clinical relevance of the results is discussed.

Self-Injurious Behavior: An Animal Model of an Autism Endophenotype

DTIC Science & Technology

2012-01-01

time there was a visible release of the pasta (not a drop) or a reformation of the digits holding the pasta via motor patterns of flexion/extension...review of 18 pasta -trials, nine trials randomly selected from each experimental group. Behaviors included on the code sheet were number of drops...failure to contact reaches, angling with head tilt, abnormal posture, use of a unilateral paw technique, and twirling of the pasta . Specific descriptions

The association of foot arch posture and prior history of shoulder or elbow surgery in elite-level baseball pitchers.

PubMed

Feigenbaum, Luis A; Roach, Kathryn E; Kaplan, Lee D; Lesniak, Bryson; Cunningham, Sean

2013-11-01

Case-control. The specific aim of this study was to examine the association between abnormal foot arch postures and a history of shoulder or elbow surgery in baseball pitchers. Pitching a baseball generates forces throughout the musculoskeletal structures of the upper and lower limbs. Structures such as the longitudinal arch of the foot are adaptable to stresses over time. Repeated pitching-related stresses may contribute to acquiring abnormal foot arch postures. Inversely, congenitally abnormal foot arch posture may lead to altered stresses of the upper limb during pitching. A convenience sample of 77 pitchers was recruited from a Division I university team and a professional baseball franchise. Subjects who had a history of shoulder or elbow surgery to the pitching arm were classified as cases. Subjects who met the criteria for classification of pes planus or pes cavus based on longitudinal arch angle were classified as having abnormal foot arch posture. Odds ratios were calculated to examine the association between abnormal foot arch posture and pitching-arm injury requiring surgery. Twenty-three subjects were classified as cases. The odds of being a case were 3.4 (95% confidence interval: 1.2, 9.6; P = .02) times greater for subjects with abnormal foot arch posture and 2.9 (95% confidence interval: 1.0, 8.1; P = .04) times greater for subjects with abnormal foot posture on the lunge leg. Abnormal foot arch posture and a surgical history in the pitching shoulder or elbow may be associated. Because the foot and its arches are adaptable and change over time, the pathomechanics of this association should be further explored.

Surgical management of anomalous head posture because of horizontal gaze palsy or acquired vertical nystagmus.

PubMed

Campos, E C; Schiavi, C; Bellusci, C

2003-07-01

To confirm the effectiveness of the Kestenbaum-Anderson principle in the surgical management of compensatory head posture because of horizontal gaze palsy and acquired vertical nystagmus. Nine patients with anomalous head posture because of horizontal gaze palsy, and four patients with acquired vertical nystagmus and oscillopsia and compensatory torticollis underwent surgery according to the Kestenbaum-Anderson principle. As in the treatment of congenital nystagmus, the eyes have to be shifted in the orbits, in the direction of anomalous head posture. Homonymously based prisms were used preoperatively to assess the potential benefit of surgery. At the time of surgery, the clinical conditions of the patients had been stable for at least 1 year. After surgery, compensatory head posture and visual performances improved in all cases and the results remained stable for at least 2 years. Contrary to what is generally believed, the ocular condition of the patients with compensatory head posture secondary to neurological causes can be often improved with surgery. The aim of surgery is obviously not to modify ocular motility, but rather to improve the head position.

Changes in maximum bite force related to extension of the head.

PubMed

Hellsing, E; Hagberg, C

1990-05-01

The maximum bite force and position of the hyoid bone during natural and extended head posture were studied in 15 adults. All participants had normal occlusions and full dentitions. In addition, there were no signs or symptoms of craniomandibular disorders. The bite force was measured with a bite force sensor placed between the first molars. Six registrations of gradually increasing bite force up to a maximum were made with randomized natural and extended head postures. With one exception, the mean maximum bite force value was found to be higher for every subject with extended head posture compared to natural head posture. The sample mean was 271.6 Newton in natural head posture and 321.5 Newton with 20 degrees extension. With changed head posture, the cephalometric measurements pointed towards a changed position of the hyoid bone in relation to the mandible and pharyngeal airway. The cephalometric changes in the position of the hyoid bone could be due to a changed interplay between the elevator and depressor muscle groups. This was one factor which could have influenced the registered maximum bite force.

Neck muscle activation and head postures in common high performance aerial combat maneuvers.

PubMed

Netto, Kevin J; Burnett, Angus F

2006-10-01

Neck injuries are common in high performance combat pilots and have been attributed to high gravitational forces and the non-neutral head postures adopted during aerial combat maneuvers. There is still little known about the pathomechanics of these injuries. Six Royal Australian Air Force Hawk pilots flew a sortie that included combinations of three +Gz levels (1, 3, and 5) and four head postures (Neutral, Turn, Extension, and Check-6). Surface electromyography from neck and shoulder muscles was recorded in flight. Three-dimensional measures of head postures adopted in flight were estimated postflight with respect to end-range of the cervical spine using an electromagnetic tracking device. Mean muscle activation increased significantly with both increasing +Gz and non-neutral head postures. Check-6 at +5 Gz (mean activation of all muscles = 51% MVIC) elicited significantly greater muscle activation in most muscles when compared with Neutral, Extension, and Turn head postures. High levels of muscle co-contraction were evident in high acceleration and non-neutral head postures. Head kinematics showed Check-6 was closest to end-range in any movement plane (86% ROM in rotation) and produced the greatest magnitude of rotation in other planes. Turn and Extension showed a large magnitude of rotation with reference to end-range in the primary plane of motion but displayed smaller rotations in other planes. High levels of neck muscle activation and co-contraction due to high +Gz and head postures close to end range were evident in this study, suggesting the major influence of these factors on the pathomechanics of neck injuries in high performance combat pilots.

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

PubMed

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.

The effect of neck torsion on postural stability in subjects with persistent whiplash.

PubMed

Yu, Li-Ju; Stokell, Raina; Treleaven, Julia

2011-08-01

Dysfunction of cervical receptors in neck disorders has been shown to lead to disturbances in postural stability. The neck torsion manoeuvre used in the smooth pursuit neck torsion (SPNT) test is thought to be a specific measure of neck afferent dysfunction on eye movement in those with neck pain. This study aimed to determine whether neck torsion could change balance responses in those with persistent whiplash-associated disorders (WADs). Twenty subjects with persistent WAD and 20 healthy controls aged between 18 and 50 years stood on a computerised force plate with eyes closed in comfortable stance under 5 conditions: neutral head, head turned to left and right and neck torsion to left and right. Root mean square (rms) amplitude of sway was measured in the anterior-posterior (AP) and medial-lateral (ML) directions. The whiplash group had significantly greater rms amplitude in the AP direction following neck torsion compared to the control group (p < 0.03). The results show that the neck torsion manoeuvre may lead to greater postural deficits in individuals with persistent WAD and provides further evidence of neck torsion to identify abnormal cervical afferent input, as an underlying cause of balance disturbances in WAD. Further research is warranted. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Atlantoaxial Rotatory Subluxation: A Review for the Pediatric Emergency Physician.

PubMed

Kinon, Merritt D; Nasser, Rani; Nakhla, Jonathan; Desai, Rupen; Moreno, Jessica R; Yassari, Reza; Bagley, Carlos A

2016-10-01

Pediatric emergency physicians must have a high clinical suspicion for atlantoaxial rotatory subluxation (AARS), particularly when a child presents with neck pain and an abnormal head posture without the ability to return to a neutral position. As shown in the neurosurgical literature, timely diagnosis and swift initiation of treatment have a greater chance of treatment success for the patient. However, timely treatment is complicated because torticollis can result from a variety of maladies, including: congenital abnormalities involving the C1-C2 joint or the surrounding supporting muscles and ligaments, central nervous system abnormalities, obstetric palsies from brachial plexus injuries, clavicle fractures, head and neck surgery, and infection. The treating pediatrician must discern the etiology of the underlying problem to determine both timing and treatment paradigms, which vary widely between these illnesses. We present a comprehensive review of AARS that is intended for pediatric emergency physicians. Management of AARS can vary widely bases on factors, such as duration of symptoms, as well as the patient's history. The goal of this review is to streamline the management paradigms and provide an inclusive review for pediatric emergency first responders.

Validity and reliability of head posture measurement using Microsoft Kinect.

PubMed

Oh, Baek-Lok; Kim, Jongmin; Kim, Jongshin; Hwang, Jeong-Min; Lee, Jehee

2014-11-01

To investigate the validity and reliability of Microsoft Kinect-based head tracker (KHT) for measuring head posture. Considering the cervical range of motion (CROM) as a reference, one-dimensional and three-dimensional (1D and 3D) head postures of 12 normal subjects (28-58 years of age; 6 women and 6 men) were obtained using the KHT. The KHT was validated by Pearson's correlation coefficient and intraclass correlation (ICC) coefficient. Test-retest reliability of the KHT was determined by its 95% limit of agreement (LoA) with the Bland-Altman plot. Face recognition success rate was evaluated for each head posture. Measurements of 1D and 3D head posture performed using the KHT were very close to those of the CROM with correlation coefficients of 0.99 and 0.97 (p<0.05), respectively, as well as with an ICC of >0.99 and 0.98, respectively. The reliability tests of the KHT in terms of 1D and 3D head postures had 95% LoA angles of approximately ±2.5° and ±6.5°, respectively. The KHT showed good agreement with the CROM and relatively favourable test-retest reliability. Considering its high performance, convenience and low cost, KHT could be clinically used as a head posture-measuring system. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Destabilization of Human Balance Control by Static and Dynamic Head Tilts

NASA Technical Reports Server (NTRS)

Paloski, William H.; Wood, Scott J.; Feiveson, Alan H.; Black, F. Owen; Hwang, Emma Y.; Reschke, Millard F.

2004-01-01

To better understand the effects of varying head movement frequencies on human balance control, 12 healthy adult humans were studied during static and dynamic (0.14,0.33,0.6 Hz) head tilts of +/-30deg in the pitch and roll planes. Postural sway was measured during upright stance with eyes closed and altered somatosensory inputs provided by a computerized dynamic posturography (CDP) system. Subjects were able to maintain upright stance with static head tilts, although postural sway was increased during neck extension. Postural stability was decreased during dynamic head tilts, and the degree of destabilization varied directly with increasing frequency of head tilt. In the absence of vision and accurate foot support surface inputs, postural stability may be compromised during dynamic head tilts due to a decreased ability of the vestibular system to discern the orientation of gravity.

Contribution of Head Position, Standing Surface, and Vision to Postural Control in Community-Dwelling Older Adults.

PubMed

Pociask, Fredrick D; DiZazzo-Miller, Rosanne; Goldberg, Allon; Adamo, Diane E

2016-01-01

Postural control requires the integration of sensorimotor information to maintain balance and to properly position and orient the body in response to external stimuli. Age-related declines in peripheral and central sensory and motor function contribute to postural instability and falls. This study investigated the contribution of head position, standing surface, and vision on postural sway in 26 community-dwelling older adults. Participants were asked to maintain a stable posture under conditions that varied standing surface, head position, and the availability of visual information. Significant main and interaction effects were found for all three factors. Findings from this study suggest that postural sway responses require the integration of available sources of sensory information. These results have important implications for fall risks in older adults and suggest that when standing with the head extended and eyes closed, older adults may place themselves at risk for postural disequilibrium and loss of balance. Copyright © 2016 by the American Occupational Therapy Association, Inc.

Integration of Osteopathic Manual Treatments in Management of Cervical Dystonia with Tremor: A Case Series

PubMed Central

Halimi, Miriam; Leder, Adena; Mancini, Jayme D.

2017-01-01

Background Cervical dystonia, also known as spasmodic torticollis, is a chronic disorder in which patients exhibit involuntary repetitive contractions of neck muscles resulting in abnormal postures or movements. Occasionally, there is also a dystonic head tremor. The underlying mechanisms for cervical dystonia and dystonic tremor are not clear, and treatments are limited. Case Report In the present cases, two females with head tremor starting in adolescence developed worsening symptoms of cervical dystonia with dystonic tremor in their 60s. On osteopathic physical examination, both had a vertical type strain to the sphenobasilar synchondrosis. Discussion Vertical strains are more frequently found in patients after head trauma, congenital or later in life, than in healthy patients, and head trauma may have been a precipitating factor in these patients. There were improvements in cervical dystonia symptoms, including tremor, in both patients after osteopathic manual treatment. PMID:28119789

Head movements and postures as pain behavior

PubMed Central

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

Head Position Comparison between Students with Normal Hearing and Students with Sensorineural Hearing Loss.

PubMed

Melo, Renato de Souza; Amorim da Silva, Polyanna Waleska; Souza, Robson Arruda; Raposo, Maria Cristina Falcão; Ferraz, Karla Mônica

2013-10-01

Introduction Head sense position is coordinated by sensory activity of the vestibular system, located in the inner ear. Children with sensorineural hearing loss may show changes in the vestibular system as a result of injury to the inner ear, which can alter the sense of head position in this population. Aim Analyze the head alignment in students with normal hearing and students with sensorineural hearing loss and compare the data between groups. Methods This prospective cross-sectional study examined the head alignment of 96 students, 48 with normal hearing and 48 with sensorineural hearing loss, aged between 7 and 18 years. The analysis of head alignment occurred through postural assessment performed according to the criteria proposed by Kendall et al. For data analysis we used the chi-square test or Fisher exact test. Results The students with hearing loss had a higher occurrence of changes in the alignment of the head than normally hearing students (p < 0.001). Forward head posture was the type of postural change observed most, occurring in greater proportion in children with hearing loss (p < 0.001), followed by the side slope head posture (p < 0.001). Conclusion Children with sensorineural hearing loss showed more changes in the head posture compared with children with normal hearing.

Head Position Comparison between Students with Normal Hearing and Students with Sensorineural Hearing Loss

PubMed Central

Melo, Renato de Souza; Amorim da Silva, Polyanna Waleska; Souza, Robson Arruda; Raposo, Maria Cristina Falcão; Ferraz, Karla Mônica

2013-01-01

Introduction Head sense position is coordinated by sensory activity of the vestibular system, located in the inner ear. Children with sensorineural hearing loss may show changes in the vestibular system as a result of injury to the inner ear, which can alter the sense of head position in this population. Aim Analyze the head alignment in students with normal hearing and students with sensorineural hearing loss and compare the data between groups. Methods This prospective cross-sectional study examined the head alignment of 96 students, 48 with normal hearing and 48 with sensorineural hearing loss, aged between 7 and 18 years. The analysis of head alignment occurred through postural assessment performed according to the criteria proposed by Kendall et al. For data analysis we used the chi-square test or Fisher exact test. Results The students with hearing loss had a higher occurrence of changes in the alignment of the head than normally hearing students (p < 0.001). Forward head posture was the type of postural change observed most, occurring in greater proportion in children with hearing loss (p < 0.001), followed by the side slope head posture (p < 0.001). Conclusion Children with sensorineural hearing loss showed more changes in the head posture compared with children with normal hearing. PMID:25992037

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

PubMed

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.

Are automatic postural responses in patients with Parkinson's disease abnormal due to their stooped posture?

PubMed

Bloem, B R; Beckley, D J; van Dijk, J G

1999-02-01

Abnormal automatic postural responses are thought to contribute to balance impairment in Parkinson's disease. However, because postural responses are modifiable by stance, we have speculated that some postural abnormalities in patients with Parkinson's disease are secondary to their stooped stance. We have studied this assumption by assessing automatic postural responses in 30 healthy subjects who were instructed either to stand upright or to assume a typical parkinsonian posture. During both conditions, subjects received 20 serial 4 degrees 'toe-up' rotational perturbations from a supporting forceplate. We recorded short-latency (SL) and medium-latency (ML) responses from stretched gastrocnemius muscles and long-latency (LL) responses from shortened tibialis anterior muscles. We also assessed changes in the center of foot pressure (CFP) and the center of gravity (COG). The results were qualitatively compared to a previously described group of patients with Parkinson's disease who, under these circumstances, typically have large ML responses, small LL responses and insufficient voluntary postural corrections, accompanied by a slow rate of backward CFP displacement and an increased posterior COG displacement. The stooped posture resulted in unloading of medial gastrocnemius muscles and loading of tibialis anterior muscles. Onset latencies of stretch responses in gastrocnemius muscles were delayed in stooped subjects, but the onset of LL responses was markedly reduced. Amplitudes of both ML and LL responses were reduced in stooped subjects. Prestimulus COG and, to a lesser extent, CFP were shifted forwards in stooped subjects. Posterior COG displacement and the rate of backward CFP displacement were diminished in stooped subjects. Voluntary postural corrections were unchanged while standing stooped. These results indicate that some postural abnormalities of patients with Parkinson's disease (most notably the reduced LL responses) can be reproduced in healthy subjects mimicking a stooped parkinsonian posture. Other postural abnormalities (most notably the increased ML responses and insufficient voluntary responses) did not appear in stooped controls and may contribute to balance impairment in Parkinson's disease.

Mandibular deviations in TMD and non-TMD groups related to eye dominance and head posture.

PubMed

Pradham, N S; White, G E; Mehta, N; Forgione, A

2001-01-01

This study was designed to determine whether eye-dominance affects head posture (rotation) and in turn, whether head posture is associated with mandibular frenum midline deviation, in both TMJ and control subjects. Eye dominance was determined using three tests: Porta, Hole, Point tests. Natural head posture was evaluated using the Arthrodial protractor. Mandibular frenum deviation was recorded as left, right or no deviation. Fifty female subjects were included in the study, 25 TMJ patients attending the Gelb Craniomandibular Pain Center and 25 non-TMJ control subjects. The findings indicate that eye dominance and direction of head rotation are strongly associated in both TMJ and control subjects. Further, in TMJ subjects mandibular deviation occurred in greater frequency than in controls and tends to occur in the contra lateral direction of head rotation.

Assessment of forward head posture in females: observational and photogrammetry methods.

PubMed

Salahzadeh, Zahra; Maroufi, Nader; Ahmadi, Amir; Behtash, Hamid; Razmjoo, Arash; Gohari, Mahmoud; Parnianpour, Mohamad

2014-01-01

There are different methods to assess forward head posture (FHP) but the accuracy and discrimination ability of these methods are not clear. Here, we want to compare three postural angles for FHP assessment and also study the discrimination accuracy of three photogrammetric methods to differentiate groups categorized based on observational method. All Seventy-eight healthy female participants (23 ± 2.63 years), were classified into three groups: moderate-severe FHP, slight FHP and non FHP based on observational postural assessment rules. Applying three photogrammetric methods - craniovertebral angle, head title angle and head position angle - to measure FHP objectively. One - way ANOVA test showed a significant difference in three categorized group's craniovertebral angle (P< 0.05, F=83.07). There was no dramatic difference in head tilt angle and head position angle methods in three groups. According to Linear Discriminate Analysis (LDA) results, the canonical discriminant function (Wilks'Lambda) was 0.311 for craniovertebral angle with 79.5% of cross-validated grouped cases correctly classified. Our results showed that, craniovertebral angle method may discriminate the females with moderate-severe and non FHP more accurate than head position angle and head tilt angle. The photogrammetric method had excellent inter and intra rater reliability to assess the head and cervical posture.

A High Prevalence of Exotropia in Patients With Duane Retraction Syndrome in a Tertiary Eye Care Center in South India.

PubMed

Bhate, Manjushree; Sachdeva, Virender; Kekunnaya, Ramesh

2017-03-01

To determine the prevalence and clinical characteristics of patients with Duane retraction syndrome presenting with exotropia in a tertiary eye care center. Medical records of 140 patients with Duane retraction syndrome and exotropia (of the total 441 patients with Duane retraction syndrome) seen from 2000 to 2009 were reviewed. Characteristics studied included age at presentation, gender, laterality, manifest primary position, abnormal head posture, ocular motility, and overshoots. Data were collected regarding associated ocular or systemic abnormalities and amblyopia. The mean age of the patients at presentation was 16.96 ± 15.09 years (range: 1 to 70 years). Of the 140 patients with Duane retraction syndrome and exotropia, 59 (42%) were male. Unilateral type I Duane retraction syndrome accounted for 118 (84.2%), type II for 7 (5%), and type III for 10 (7.1%) patients, whereas 5 (3.6%) had Duane retraction syndrome and bilateral exotropia. Duane retraction syndrome was seen in the left eye, right eye, and both eyes in 97 (69%), 37 (26%), and 6 (4%) patients, respectively. Exotropia ranged from 10 to 60 prism diopters. An abnormal head posture was noted in 101 (72%) and upshoot in 26 (18.6%) patients. Reported ocular and systemic abnormalities in these patients included cataract (6), aniridia (1), nasolacrimal duct block (1), and retinal breaks (1). This is an exclusive study on a large series of patients with Duane retraction syndrome and exotropia. Almost one-third of patients with Duane retraction syndrome patients might have exotropia. Although patients with Duane retraction syndrome and exotropia had clinical characteristics and associations similar to those with Duane retraction syndrome and esotropia, there was an increased propensity for overshoots and face turn opposite to the affected eye, which the authors hypothesize to be due to a tight or short lateral rectus muscle. [J Pediatr Ophthalmol Strabismus. 2017;54(2):117-122.]. Copyright 2017, SLACK Incorporated.

The internal representation of head orientation differs for conscious perception and balance control

PubMed Central

Dalton, Brian H.; Rasman, Brandon G.; Inglis, J. Timothy

2017-01-01

Key points We tested perceived head‐on‐feet orientation and the direction of vestibular‐evoked balance responses in passively and actively held head‐turned postures.The direction of vestibular‐evoked balance responses was not aligned with perceived head‐on‐feet orientation while maintaining prolonged passively held head‐turned postures. Furthermore, static visual cues of head‐on‐feet orientation did not update the estimate of head posture for the balance controller.A prolonged actively held head‐turned posture did not elicit a rotation in the direction of the vestibular‐evoked balance response despite a significant rotation in perceived angular head posture.It is proposed that conscious perception of head posture and the transformation of vestibular signals for standing balance relying on this head posture are not dependent on the same internal representation. Rather, the balance system may operate under its own sensorimotor principles, which are partly independent from perception. Abstract Vestibular signals used for balance control must be integrated with other sensorimotor cues to allow transformation of descending signals according to an internal representation of body configuration. We explored two alternative models of sensorimotor integration that propose (1) a single internal representation of head‐on‐feet orientation is responsible for perceived postural orientation and standing balance or (2) conscious perception and balance control are driven by separate internal representations. During three experiments, participants stood quietly while passively or actively maintaining a prolonged head‐turned posture (>10 min). Throughout the trials, participants intermittently reported their perceived head angular position, and subsequently electrical vestibular stimuli were delivered to elicit whole‐body balance responses. Visual recalibration of head‐on‐feet posture was used to determine whether static visual cues are used to update the internal representation of body configuration for perceived orientation and standing balance. All three experiments involved situations in which the vestibular‐evoked balance response was not orthogonal to perceived head‐on‐feet orientation, regardless of the visual information provided. For prolonged head‐turned postures, balance responses consistent with actual head‐on‐feet posture occurred only during the active condition. Our results indicate that conscious perception of head‐on‐feet posture and vestibular control of balance do not rely on the same internal representation, but instead treat sensorimotor cues in parallel and may arrive at different conclusions regarding head‐on‐feet posture. The balance system appears to bypass static visual cues of postural orientation and mainly use other sensorimotor signals of head‐on‐feet position to transform vestibular signals of head motion, a mechanism appropriate for most daily activities. PMID:28035656

Evaluation of posture and pain in persons with benign joint hypermobility syndrome.

PubMed

Booshanam, Divya S; Cherian, Binu; Joseph, Charles Premkumar A R; Mathew, John; Thomas, Raji

2011-12-01

The objective of the present study is to compare and quantify the postural differences and joint pain distribution between subjects with benign joint hypermobility syndrome (BJHS) and the normal population. This observational, non-randomized, and controlled study was conducted at Rheumatology and Physical Medicine and Rehabilitation Medicine Departments of a tertiary care teaching hospital. Subjects comprise 35 persons with diagnosis of BJHS, and the control group was matched for age and sex. Reedco's Posture score (RPS) and visual analogue scale (VAS) were the outcome measures. The subjects were assessed for pain in ten major joints and rated on a VAS. A standard posture assessment was conducted using the Reedco's Posture score. The same procedure was executed for an age- and sex-matched control group. Mean RPS for the BJHS group was 55.29 ± 8.15 and for the normal group it was 67 ± 11.94. The most common postural deviances in subjects with BJHS were identified in the following areas of head, hip (Sagittal plane), upper back, trunk, and lower back (Coronal plane). Intensity of pain was found to be more in BJHS persons than that of the normal persons, and the knee joints were the most affected. The present study compared and quantified the postural abnormalities and the pain in BJHS persons. The need for postural re-education and specific assessment and training for the most affected joints are discussed. There is a significant difference in posture between subjects with BJHS and the normal population. BJHS persons need special attention to their posture re-education during physiotherapy sessions to reduce long-term detrimental effects on the musculoskeletal system.

Tetra-ataxiometric Posturography in Patients with Migrainous Vertigo.

PubMed

Ongun, Nedim; Atalay, Nilgun S; Degirmenci, Eylem; Sahin, Fusun; Bir, Levent Sinan

2016-01-01

Migraine is a common disorder characterized by headache attacks frequently accompanied by vestibular symptoms like dizziness, vertigo, and balance disorders. Clinical studies support a strong link between migraine and vertigo rather than between other headache types and vertigo or nonvertiginous dizziness. There is a lack of consensus regarding the pathophysiology of migrainous vertigo. Activation of central vestibular processing during migraine attacks and vasospasm-induced ischemia of the labyrinth are reported as the probable responsible mechanisms. Because vestibular examination alone does not provide enough information for diagnosis of migrainous vertigo, posturography systems which provide objective assessment of somatosensory, vestibular, and visual information would be very helpful to show concomitant involvement of the vestibular and somato-sensorial systems. There are few posturographic studies on patients with migraine but it seems that how balance is affected in patients with migraine and/or migrainous vertigo is still not clear. We want to investigate balance function in migraineurs with and without vertigo with a tetra-ataxiometric posturography system and our study is the first study in which tetra-ataxiometric static posturography was used to evaluate postural abnormalities in a well-defined population of patients with migrainous vertigo. To investigate balance functions in migraineurs with and without vertigo with a tetra-ataxiometric posturography system. Prospective, nonrandomized, controlled study. Pamukkale University Hospital, Neurology and Physical Therapy and Rehabilitation outpatient clinics. Sixteen patients with migrainous vertigo, 16 patients with migraine without aura and no vestibular symptoms, and 16 controls were included in the study. Computerized static posturography system was performed and statistical analyses of fall, Fourier, Stability, and Weight distribution indexes were performed. The tetra-ataxiometric posturography device measures vertical pressure fluctuations on 4 independent stable platforms, each placed beneath 2 heels and toe parts of the patient; inputs from these platforms are integrated and processed by a computer digitally. Four separate plates are used and perpendicular pressures of the anterior and posterior feet are measured. Pressure of each force plate is measured and data was analyzed by the software program. A very small, non-randomized, and controlled study with the inability to find an answer to the mechanism of involvement of the somatosensorial system and vestibular system in migrainous headaches. The distribution of patients with posturographical abnormalities in the migrainous vertigo group was significantly different than the control group. Distribution of the patients with posturographical abnormalities in the high frequencies of the head-right position was significantly different in the migrainous vertigo group than in the control group and distribution of the patients with posturographical abnormalities in high frequencies of the head-right position was significantly different in the migraine group than in the controls groups. The stability index of the migrainous vertigo group was significantly higher than in the control group when tested on in the neutral-head position with open eyes. In this first study of tetra-ataxiometric static posturography evaluating postural abnormalities in a well-defined population of patients with migrainous vertigo, the central part of the vestibular apparatus would be responsible of postural abnormalities in patients with migraine and migrainous vertigo.

Facial type and head posture of nasal and mouth-breathing children.

PubMed

Bolzan, Geovana de Paula; Souza, Juliana Alves; Boton, Luane de Moraes; Silva, Ana Maria Toniolo da; Corrêa, Eliane Castilhos Rodrigues

2011-12-01

To verify the facial type and the head posture of nasal and mouth-breathing children from habitual and obstructive etiologies, as well as to correlate the morphological facial index to the head angulation position in the sagittal plane. Participants were 59 children with ages between 8 years and 11 years and 10 months. All subjects were undergone to speech-language pathology screening, otorhinolaryngologic evaluation, and nasopharyngoscopy, allowing the constitution of three groups: nasal breathers--15 children; mouth breathers from obstructive etiology--22 children; and habitual mouth breathers--22 children. In order to determine facial type and morphological facial index, the height and the width of the face were measured using a digital caliper. The head posture was assessed through physical examination and computerized photogrammetry. It was verified the predominance of short face in nasal breathers, and long face in mouth breathers. There was an association among facial type and breathing mode/mouth breathing etiology: the brachyfacial type was more frequent among nasal breathers, and less frequent in subjects with obstructive nasal breathing. Head posture was similar in all three groups. No correlation was found between morphological facial index and head posture. The brachyfacial type favors the nasal-breathing mode and the head posture is not influenced by breathing mode and by the etiology of mouth breathing, as well as it is not related to facial type.

The association between head and cervical posture and temporomandibular disorders: a systematic review.

PubMed

Olivo, Susan Armijo; Bravo, Jaime; Magee, David J; Thie, Norman M R; Major, Paul W; Flores-Mir, Carlos

2006-01-01

To carry out a systematic review to assess the evidence concerning the association between head and cervical posture and temporomandibular disorders (TMD). A search of Medline, Pubmed, Embase, Web of Science, Lilacs, and Cochrane Library databases was conducted in all languages with the help of a health sciences librarian. Key words used in the search were posture, head posture, cervical spine or neck, vertebrae, cervical lordosis, craniomandibular disorders or temporomandibular disorders, temporomandibular disorders, and orofacial pain or facial pain. Abstracts which appeared to fulfill the initial selection criteria were selected by consensus. The original articles were retrieved and evaluated to ensure they met the inclusion criteria. A methodological checklist was used to evaluate the quality of the selected articles and their references were hand-searched for possible missing articles. Twelve studies met all inclusion criteria and were analyzed in detail for their methodology and information quality. Nine articles that analyzed the association between head posture and TMD included patients with mixed TMD diagnosis; 1 article differentiated among muscular, articular, and mixed symptomatology; and 3 articles analyzed information from patients with only articular problems. Finally, 2 studies evaluated the association between head posture and TMD in patients with muscular TMD. Several methodological defects were noted in the 12 studies. Since most of the studies included in this systematic review were of poor methodological quality, the findings of the studies should be interpreted with caution. The association between intra-articular and muscular TMD and head and cervical posture is still unclear, and better controlled studies with comprehensive TMD diagnoses, greater sample sizes, and objective posture evaluation are necessary.

Decorticate posture

MedlinePlus

Abnormal posturing - decorticate posture; Traumatic brain injury - decorticate posture ... Brain problem due to drugs, poisoning, or infection Traumatic brain injury Brain problem due to liver failure Increased pressure ...

Postural Complexity Differs Between Infant Born Full Term and Preterm During the Development of Early Behaviors

PubMed Central

Dusing, Stacey C; Izzo, Theresa A.; Thacker, Leroy R.; Galloway, James C

2014-01-01

Background and Aims Postural control differs between infants born preterm and full term at 1–3 weeks of age. It is unclear if differences persist or alter the development of early behaviors. The aim of this longitudinal study was to compare changes in postural control variability during development of head control and reaching in infants born preterm and full term. Methods Eighteen infants born preterm (mean gestational age 28.3±3.1 weeks) were included in this study and compared to existing data from 22 infants born full term. Postural variability was assessed longitudinally using root mean squared displacement and approximate entropy of the center of pressure displacement from birth to 6 months as measures of the magnitude of the variability and complexity of postural control. Behavioral coding was used to quantify development of head control and reaching. Results Group differences were identified in postural complexity during the development of head control and reaching. Infants born preterm used more repetitive and less adaptive postural control strategies than infants born full term. Both groups changed their postural complexity utilized during the development of head control and reaching. Discussion Early postural complexity was decreased in infants born preterm, compared to infants born full term. Commonly used clinical assessments did not identify these early differences in postural control. Altered postural control in infants born preterm influenced ongoing skill development in the first six months of life. PMID:24485170

Gait Balance Disorder by Thalamic Infarction with the Disorder of Interstitial Nucleus of Cajal

PubMed Central

Kurosu, A.; Hayashi, Y.; Wada, K.; Nagaoka, M.

2011-01-01

The interstitial nucleus of Cajal (INC) is thought to play an important role in torsional/vertical eye position and head posture, and disorders of the INC induce abnormal ocular movements and head tilt. Our patients with ocular tilt reactions simultaneously also had disturbances in ambulatory balance, yet no reports address the loss of balance control induced by disorders of the INC. We examined the ambulatory disturbances induced by INC lesion. We experienced three patients with ocular movement disorders and abnormal head tilt due to thalamic infarction. We performed ophthalmic examinations on and checked the balance of them. With funduscopy, abnormal cycloduction was seen in the unaffected side and normal cycloduction was observed in the affected side. Nevertheless, Hess charts showed distortions in the visual image of both eyes. They all had disorders of balance control. We tried to treat them using the Bobath approach for improving their ambulatory balance. With subsequent improvements in balance control it was possible for them to take short walks, but it was difficult to make any improvements in their ocular movement. The INC is related to balance control of ambulation and disorders of the INC induce ambulatory disturbances. Cycloduction was only observed in the unaffected side, but Hess charts showed distortions of the visual image in both eyes. Ambulation was briefly improved, but diplopia persisted in these patients. PMID:21769260

Head and cervical spine postures in complete denture wearers.

PubMed

Salonen, M A; Raustia, A M; Huggare, J

1993-01-01

Signs and symptoms in the stomatognathic system and head and cervical spine postures were evaluated in 10 edentulous patients prior to renewal of their dentures, as well as immediately and six months after insertion of new dentures. Natural head posture was recorded using the fluid-level method and measured from the roentgen cephalograms. It was shown that the variables duration of edentulousness and free-way space displayed positive correlations with the dysfunction symptoms. In addition, the patients who needed oral rehabilitation the most, who received the greatest reduction in their free-way space, were seen to have raised their heads more than average. There was also an inverse correlation between the reduction of clinical dysfunction index score and cervical spine postures.

Use of the Occivator for the correction of forward head posture, and the implications for temporomandibular disorders: a pilot study.

PubMed

Augustine, Catherine; Makofsky, Howard W; Britt, Christina; Adomsky, Barbara; Deshler, Jennifer Matire; Ramirez, Paula; Douris, Peter

2008-04-01

Numerous studies suggest that temporomandibular disorders may be associated with forward head posture. The current study presents a need for an intervention that will effectively facilitate an ideal postural alignment of the head. The Occivator (Posteocentric Systems, Mastic Beach, NY) is an intervention speculated to improve forward head posture (FHP). However there has not been a randomized study to correlate use of the Occivator with improvement of FHP. The purpose of this study was to evaluate the effectiveness of the Occivator as a therapeutic intervention for the correction of FHP. Using a plumb line, twenty-nine (29) subjects were selected on the basis of having FHP. The CROM (cervical range of motion) device was used to determine measurement of forward head position for each group, pre and post an eight week period. The experimental group followed a specific protocol of 20 minutes of stretches and exercises on the Occivator, two times a week for eight weeks. The control group did not receive any intervention. The experimental group as compared to the control group, demonstrated significant improvement for forward head posture (p = .02). Further research is needed to evaluate the effectiveness of the Occivator.

[Management of positional head deformity in 31 infants].

PubMed

Pan, Wei-Wei; Tong, Xiao-Mei

2017-02-01

To investigate the clinical effect of postural correction training and helmet therapy in the treatment of moderate-severe positional head deformity defined as asymmetric head shape in infants. A total of 31 infants who were diagnosed with moderate-severe plagiocephaly and/or brachiocephaly were enrolled. According to the different treatment methods, the infants were divided into helmet therapy group with 11 infants and postural correction training group with 20 infants. The cranial vault asymmetry index (CVAI), cephalic ratio (CR), and head circumference growth were compared between the two groups before and after treatment. Compared with the postural correction training group, the helmet therapy group had significantly lower CVAI and CR after treatment. The helmet therapy group had significantly better improvements in CVAI and CR after treatment compared with the postural correction training group (CVAI difference: 6.0±1.9 vs 0.7±0.8, P=0.001; CR difference: 0.047±0.009 vs 0.008±0.005, P<0.001). There was no significant difference in head circumference growth between the two groups (P=0.55). Helmet therapy has a significantly better effect in the treatment of moderate-severe positional head deformity than postural correction training in infants. Helmet therapy does not limit head circumference growth.

Space flight and neurovestibular adaptation

NASA Technical Reports Server (NTRS)

Reschke, M. F.; Bloomberg, J. J.; Harm, D. L.; Paloski, W. H.

1994-01-01

Space flight represents a form of sensory stimulus rearrangement requiring modification of established terrestrial response patterns through central reinterpretation. Evidence of sensory reinterpretation is manifested as postflight modifications of eye/head coordination, locomotor patterns, postural control strategies, and illusory perceptions of self or surround motion in conjunction with head movements. Under normal preflight conditions, the head is stabilized during locomotion, but immediately postflight reduced head stability, coupled with inappropriate eye/head coordination, results in modifications of gait. Postflight postural control exhibits increased dependence on vision which compensates for inappropriate interpretation of otolith and proprioceptive inputs. Eye movements compensatory for perceived self motion, rather than actual head movements have been observed postflight. Overall, the in-flight adaptive modification of head stabilization strategies, changes in head/eye coordination, illusionary motion, and postural control are maladaptive for a return to the terrestrial environment.

Influence of dopaminergic medication on automatic postural responses and balance impairment in Parkinson's disease.

PubMed

Bloem, B R; Beckley, D J; van Dijk, J G; Zwinderman, A H; Remler, M P; Roos, R A

1996-09-01

It is still unclear why balance impairment in Parkinson's disease (PD) often responds insufficiently to dopaminergic medication. We have studied this issue in 23 patients with idiopathic PD and 24 healthy controls. Our specific purposes were (a) to investigate the contribution of abnormal automatic postural responses to balance impairment in PD and (b) to assess the influence of dopaminergic medication on abnormal automatic postural responses and balance impairment. Standing subjects received 4 degrees "toe-up" rotational perturbations of a supporting forceplate. We bilaterally recorded posturally destabilizing medium latency (ML) responses from the stretched gastrocnemius muscles and functionally corrective long latency (LL) responses from the shortened tibialis anterior (TA) muscles. We also assessed changes in the center of foot pressure (CFP) and the center of gravity (COG). All patients were tested in the "off" and "on" phases. All controls were tested and retested after 1 h. During the off phase, we found enlarged ML amplitudes and diminished LL amplitudes in patients, together with a markedly increased posterior displacement of the COG. The abnormal ML and LL responses were partially responsible for the increased body sway in patients because the initial forward (destabilizing) displacement of the CFP was increased, while the subsequent backward displacement of the CFP (a measure of the corrective braking action of LL responses) was delayed. Abnormal late automatic or possibly more voluntary postural corrections also contributed substantially to the increased body sway. During the on phase, ML amplitudes were reduced in patients but remained increased compared with controls. LL amplitudes no longer differed between both groups due to a modest, possibly dopamine-related increase in patients and a simultaneous decrease in controls. The abnormal CFP displacement was only partially improved by dopaminergic medication. The later postural corrections were not improved at all. Consequently, the increased posterior COG displacement was not ameliorated during the on phase. We conclude that (a) a combination of abnormal automatic and perhaps more voluntary postural corrections contributes to increased body sway in PD and (b) dopaminergic medication fails to improve balance impairment in PD because early automatic postural responses are only partially corrected, while later occurring postural corrections are not improved at all. These electrophysiological results support clinical observations and suggest that nondopaminergic lesions play a significant role in the pathophysiology of postural abnormalities in PD.

Relationship between head posture and dentofacial morphology in patients with TMJ osteoarthritis/osteoarthrosis.

PubMed

Ioi, Hideki; Matsumoto, Ryusuke; Nishioka, Masato; Goto, Tazuko K; Nakata, Shunsuke; Nakasima, Akihiko; Counts, Amy L

2008-01-01

To test whether there is a relationship between head and cervical posture and dentofacial morphology in patients with temporomandibular joint osteoarthritis/osteoarthrosis (OA). The subjects consisted of 34 Japanese females with TMJ OA (aged 24.7 +/- 6.1 years). Six craniocervical angular measurements were constructed for head posture. Two angular and 6 linear measurements were constructed for the skeletal relationship, while 1 angular and 6 linear measurements were constructed for the dental relationship. Pearson correlation coefficients were calculated between head posture and dentofacial variables. In the skeletal relationship, increased craniocervical angulations were significantly associated with a more posterior position of the maxilla, a decreased Frankfort to mandibular plane angle, decreased mandibular length, and a decreased lower facial height. In the dental relationship, increased craniocervical angulations were significantly associated with more posterior positions of the anterior teeth to the basal bone and decreased alveolar height of the anterior-posterior teeth. The hypothesis was rejected. These results suggest that an association may exist between head and cervical posture and dentofacial morphology in patients with TMJ OA.

Posture, head stability, and orientation recovery during vestibular regeneration in pigeons.

PubMed

Dickman, J David; Lim, Insook

2004-09-01

Compensatory behavior such as oculomotor, gaze, and postural responses that occur during movement largely depend upon a functioning vestibular system. In the present study, the initial loss and subsequent recovery of postural and head stability in pigeons undergoing vestibular regeneration were examined. Adult pigeons were trained to manipulate a straight run chamber to peck an illuminated key for fluid reward. Six behavioral measures assessing performance, posture, and head stability were quantified. These included run latency, steps (walking), path negotiation (lane changes), gaze saccades, head bobs, and head shakes. Once normative values were obtained for four birds, complete lesion of all receptor cells and denervation of the epithelia in the vestibular endorgans were produced using a single intralabyrinthine application of streptomycin sulfate. Each bird was then tested at specific times during regeneration and the same behavioral measures examined. At 7 days post-streptomycin treatment (PST), all birds exhibited severe postural and head instability, with tremors, head shakes, staggering, and circling predominating. No normal trial runs, walking, gaze saccades, or head bobs were present. Many of these dysfunctions persisted through 3-4 weeks PST. Gradually, tremor and head shakes diminished and were replaced with an increasing number of normal head bobs during steps and gaze saccades. Beginning at 4 weeks PST, but largely inaccurate, was the observed initiation of directed steps, less staggering, and some successful path negotiation. As regeneration progressed, spatial orientation and navigation ability increased and, by 49 days PST, most trials were successful. By 70 days PST, all birds had recovered to pretreatment levels. Thus, it was observed that ataxia must subside, coincident with normalized head and postural stability prior to the recovery of spatial orientation and path navigation recovery. Parallels in recovery were drawn to hair cell regeneration and afferent responsiveness, as inferred from present results and those in other investigations.

Effects of Kinesio taping and exercise on forward head posture.

PubMed

Shih, Hsu-Sheng; Chen, Shu-Shi; Cheng, Su-Chun; Chang, Hsun-Wen; Wu, Pei-Rong; Yang, Jin-Shiou; Lee, Yi-Shuang; Tsou, Jui-Yi

2017-01-01

Little is known about the effects of Kinesio taping and therapeutic exercise on correcting forward head posture. To compare Kinesio taping versus therapeutic exercise for forward head posture on static posture, dynamic mobility and functional outcomes. Sixty subjects (31 women, 29 men) with forward head postures participated in this study. They were randomly assigned to either one of the three groups: (1) exercise group (n = 20), (2) taping group (n = 20), and (3) control groups (n = 20). The horizontal forward displacement (HFD) between ear lobe and acromion process, upper cervical and lower cervical angle (UCA, LCA), active range of motion (AROM) of cervical spine, and neck disability index (NDI) were measured before and after a 5-week intervention, and a 2-week follow-up. Data were analyzed by means of a mixed design repeated-measures ANOVA. Both taping and exercise groups showed significant improvements in HFD compared with the control group at post-treatment and follow-up. Compared with the control group, the exercise group exhibited significant improvements in the LCA and the side bending AROM at post-treatment. Both Kinesio taping and therapeutic exercise improve forward head posture after intervention and a 2-week follow-up. The effectiveness of therapeutic exercise is better than taping.

The Evaluation of Head and Craniocervical Posture among Patients with and without Temporomandibular Joint Disorders- A Comparative Study.

PubMed

Saddu, Shweta Channavir; Dyasanoor, Sujatha; Valappila, Nidhin J; Ravi, Beena Varma

2015-08-01

Temporomandibular disorders (TMD) are the most common non-dental cause of orofacial pain with a multifactorial aetiology. To evaluate the head and craniocervical posture between individuals with and without TMD and its sub types by photographic and radiographic method. Thirty four TMD patients diagnosed according to Research Diagnostic Criteria for TMD's (RDC/TMD) and were divided into 2 groups: Group I (muscle disorder), Group II (disc displacement). Control group comprised of 34 age and sex matched subjects without TMD. Lateral view photographs were taken and the head posture angle was measured. Craniocervical posture was assessed on lateral skull radiograph with two angles (Craniocervical Angle, Cervical Curvature Angle) and two distances (Suboccipital Space, Atlas-Axis Distance). To compare the results, t-test was used with significance level of 0.05. Head posture showed no statistical significant difference (p > 0.05) between Group I, II and control group in both photographic and radiographic methods. The cervical curvature angle showed significant difference (p = 0.045) in Group I only. Atlas-Axis Distance was statistically significant in Group II (p = 0.001). The present study confirmed that there is a negative association of head posture and TMD whereas, cervical lordosis was present in Group I only.

The Evaluation of Head and Craniocervical Posture among Patients with and without Temporomandibular Joint Disorders- A Comparative Study

PubMed Central

Saddu, Shweta Channavir; Dyasanoor, Sujatha; Ravi, Beena Varma

2015-01-01

Introduction Temporomandibular disorders (TMD) are the most common non-dental cause of orofacial pain with a multifactorial aetiology. Aim To evaluate the head and craniocervical posture between individuals with and without TMD and its sub types by photographic and radiographic method. Materials and Methods Thirty four TMD patients diagnosed according to Research Diagnostic Criteria for TMD’s (RDC/TMD) and were divided into 2 groups: Group I (muscle disorder), Group II (disc displacement). Control group comprised of 34 age and sex matched subjects without TMD. Lateral view photographs were taken and the head posture angle was measured. Craniocervical posture was assessed on lateral skull radiograph with two angles (Craniocervical Angle, Cervical Curvature Angle) and two distances (Suboccipital Space, Atlas-Axis Distance). To compare the results, t-test was used with significance level of 0.05. Results Head posture showed no statistical significant difference (p > 0.05) between Group I, II and control group in both photographic and radiographic methods. The cervical curvature angle showed significant difference (p = 0.045) in Group I only. Atlas-Axis Distance was statistically significant in Group II (p = 0.001). Conclusion The present study confirmed that there is a negative association of head posture and TMD whereas, cervical lordosis was present in Group I only. PMID:26436048

Orthostatic Intolerance and Postural Orthostatic Tachycardia Syndrome in Joint Hypermobility Syndrome/Ehlers-Danlos Syndrome, Hypermobility Type: Neurovegetative Dysregulation or Autonomic Failure?

PubMed

Celletti, Claudia; Camerota, Filippo; Castori, Marco; Censi, Federica; Gioffrè, Laura; Calcagnini, Giovanni; Strano, Stefano

2017-01-01

Background . Joint hypermobility syndrome/Ehlers-Danlos syndrome, hypermobility type (JHS/EDS-HT), is a hereditary connective tissue disorder mainly characterized by generalized joint hypermobility, skin texture abnormalities, and visceral and vascular dysfunctions, also comprising symptoms of autonomic dysfunction. This study aims to further evaluate cardiovascular autonomic involvement in JHS/EDS-HT by a battery of functional tests. Methods . The response to cardiovascular reflex tests comprising deep breathing, Valsalva maneuver, 30/15 ratio, handgrip test, and head-up tilt test was studied in 35 JHS/EDS-HT adults. Heart rate and blood pressure variability was also investigated by spectral analysis in comparison to age and sex healthy matched group. Results . Valsalva ratio was normal in all patients, but 37.2% of them were not able to finish the test. At tilt, 48.6% patients showed postural orthostatic tachycardia, 31.4% orthostatic intolerance, 20% normal results. Only one patient had orthostatic hypotension. Spectral analysis showed significant higher baroreflex sensitivity values at rest compared to controls. Conclusions. This study confirms the abnormal cardiovascular autonomic profile in adults with JHS/EDS-HT and found the higher baroreflex sensitivity as a potential disease marker and clue for future research.

Postural sway and regional cerebellar volume in adults with attention-deficit/hyperactivity disorder

PubMed Central

Hove, Michael J.; Zeffiro, Thomas A.; Biederman, Joseph; Li, Zhi; Schmahmann, Jeremy; Valera, Eve M.

2015-01-01

Objective Motor abnormalities, including impaired balance and increased postural sway, are commonly reported in children with ADHD, but have yet to be investigated in adults with ADHD. Furthermore, although these abnormalities are thought to stem from cerebellar deficits, evidence for an association between the cerebellum and these motor deficits has yet to be provided for either adults or children with ADHD. Method In this study, we measured postural sway in adults with ADHD and controls, examining the relationship between sway and regional cerebellar gray matter volume. Thirty-two ADHD and 28 control participants completed various standing-posture tasks on a Wii balance board. Results Postural sway was significantly higher for the ADHD group compared to the healthy controls. Higher sway was positively associated with regional gray matter volume in the right posterior cerebellum (lobule VIII/IX). Conclusion These findings show that sway abnormalities commonly reported in children with ADHD are also present in adults, and for the first time show a relationship between postural control atypicalities and the cerebellum in this group. Our findings extend the literature on motor abnormalities in ADHD and contribute to our knowledge of their neural substrate. PMID:26106567

The relationship of forward head posture and rounded shoulders with neck pain in Iranian office workers.

PubMed

Nejati, Parisa; Lotfian, Sara; Moezy, Azar; Moezy, Azar; Nejati, Mina

2014-01-01

Background Office workers spend a long period of time behind a computer during working hours. The relation between the posture of sitting during work with computer and neck pain is still debatable. Even though some researchers claim a significant difference in head posture between patients with neck pain and pain-free participants, the FHP (forward head posture) has not always been associated with neck pain in literature. So, the purpose of this study was to discover the relationship between neck pain and improper posture in the head, cervicothoracic spine and shoulders. This was a cross-sectional study to explore the relationships between neck pains, sagittal postures of cervical and thoracic spine and shoulders among office workers in two positions, straight looking forward and working position. 46 subjects without neck pain and 55 subjects with neck pain were evaluated using a photographic method. Thoracic and cervical postures were measured by the HT (High Thoracic), CV (Craniovertebral) angles respectively. Shoulder's posture was evaluated in the sagittal plane by the acromion protrusion. HT and CV angles were positively correlated with the presence of neck pain only in working position (p< 0.05). In straight looking forward position there was no significant difference between the two groups statistically (p>0.05). The difference of shoulder protrusion between symptomatic and asymptomatic groups was not significant. FHP and thoracic kyphosis were accompanied with neck pain. But shoulder posture was not correlated with neck pain.

Space flight and changes in spatial orientation

NASA Technical Reports Server (NTRS)

Reschke, Millard F.; Bloomberg, Jacob J.; Harm, Deborah L.; Paloski, William H.

1992-01-01

From a sensory point of view, space flight represents a form of stimulus rearrangement requiring modification of established terrestrial response patterns through central reinterpretation. Evidence of sensory reinterpretation is manifested as postflight modifications of eye/head coordination, locomotor patterns, postural control strategies, and illusory perceptions of self or surround motion in conjunction with head movements. Under normal preflight conditions, the head is stabilized during locomotion, but immediately postflight reduced head stability, coupled with inappropriate eye/head coordination, results in modifications of gait. Postflight postural control exhibits increased dependence on vision which compensates for inappropriate interpretation of otolith and proprioceptive inputs. Eye movements compensatory for perceived self motion, rather than actual head movements have been observed postflight. Overall, the in-flight adaptive modification of head stabilization strategies, changes in head/eye coordination, illusionary motion, and postural control are maladaptive for a return to the terrestrial environment. Appropriate countermeasures for long-duration flights will rely on preflight adaptation and in-flight training.

Investigation of compensatory postures with videofluoromanometry in dysphagia patients

PubMed Central

Solazzo, Antonio; Monaco, Luigi; Del Vecchio, Lucia; Tamburrini, Stefania; Iacobellis, Francesca; Berritto, Daniela; Pizza, Nunzia Luisa; Reginelli, Alfonso; Di Martino, Natale; Grassi, Roberto

2012-01-01

AIM: To investigate the effectiveness of head compensatory postures to ensure safe oropharyngeal transit. METHODS: A total of 321 dysphagia patients were enrolled and assessed with videofluoromanometry (VFM). The dysphagia patients were classified as follows: safe transit; penetration without aspiration; aspiration before, during or after swallowing; multiple aspirations and no transit. The patients with aspiration or no transit were tested with VFM to determine whether compensatory postures could correct their swallowing disorder. RESULTS: VFM revealed penetration without aspiration in 71 patients (22.1%); aspiration before swallowing in 17 patients (5.3%); aspiration during swallowing in 32 patients (10%); aspiration after swallowing in 21 patients (6.5%); multiple aspirations in six patients (1.9%); no transit in five patients (1.6%); and safe transit in 169 patients (52.6%). Compensatory postures guaranteed a safe transit in 66/75 (88%) patients with aspiration or no transit. A chin-down posture achieved a safe swallow in 42/75 (56%) patients, a head-turned posture in 19/75 (25.3%) and a hyperextended head posture in 5/75 (6.7%). The compensatory postures were not effective in 9/75 (12%) cases. CONCLUSION: VFM allows the speech-language the-rapist to choose the most effective compensatory posture without a trial-and-error process and check the effectiveness of the posture. PMID:22736921

Quantitative Postural Analysis of Children With Congenital Visual Impairment.

PubMed

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 < .001), shoulder deviation in frontal plane (P = .004), lateral deviation of the spine (P < .001), changes in scapula position (P = .012), higher thoracic kyphosis (P = .004), and lower lumbar lordosis (P < .001). 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.

Early intensive postural and movement training advances head control in very young infants.

PubMed

Lee, Hui-Min; Galloway, James Cole

2012-07-01

Daily experiences are thought to play an important role in motor development during infancy. There are limited studies on the effect of postural and movement experiences on head control. The purpose of this study was to quantify the effects of postural and movement experiences on head control through a comprehensive set of measurements beginning when infants were 1 month old. This was a prospective, longitudinal, 2-cohort study. Twenty-two full-term infants who were healthy were randomly assigned to either a training group or a control group. Infants were observed every other week from 1 to 4 months of age. Head control was assessed using a standardized developmental assessment tool, the Test of Infant Motor Performance (TIMP), as well as behavioral coding and kinematics of infants' head postures and movements in a supported sitting position. Caregivers performed at least 20 minutes of daily postural and movement activities (training group), or social interaction (control group) for 4 weeks. The training group had higher TIMP scores on head control-related items during the training period and after training stopped compared with the control group. Starting from the during training phase, the training group infants had their heads in a vertical and midline position longer compared with the control group infants. After training stopped, the training group infants actively moved their heads forward more often and for larger distances. The experiences outside daily training were not monitored, and the results may be specific to the experimental setup for infants with typical development. Young infants are able to take advantage of postural and movement experiences to rapidly advance their head control as early as 4 to 6 weeks of postnatal life. Infant positioning, caregiver handling, and caregiver-infant interactions were likely contributing factors. This database of comprehensive measures may be useful in future trials focused on head control in infants with special needs.

Recurrent syncope and chronic ear pain

PubMed Central

Clegg, Andrew; Daverede, Luis; Wong, Winson; Loney, Elizabeth; Young, John

2010-01-01

An elderly gentleman presented to hospital with recurrent blackout episodes consistent with syncope and a 3-month history of right ear pain. Significant postural hypotension was recorded. White cell count and C reactive protein were elevated. MRI of the head and neck revealed a soft tissue abnormality in the right nasopharynx and base of skull. Tissue biopsies were obtained and microbiology specimens revealed a mixed growth of pseudomonas and diphtheroids. There was no histological evidence of malignancy. A diagnosis of skull base infection was made. Infective involvement of the carotid sinus was considered to be the cause of the recurrent syncope and postural hypotension. The patient responded well to a 12-week course of intravenous meropenem. Inflammatory markers returned to normal and a repeat MRI after 3 months of treatment showed significant resolution of infection. The syncopal episodes and orthostatic hypotension resolved in parallel with treatment of infection. PMID:22791782

Postural Control in Bilateral Vestibular Failure: Its Relation to Visual, Proprioceptive, Vestibular, and Cognitive Input.

PubMed

Sprenger, Andreas; Wojak, Jann F; Jandl, Nico M; Helmchen, Christoph

2017-01-01

Patients with bilateral vestibular failure (BVF) suffer from postural and gait unsteadiness with an increased risk of falls. The aim of this study was to elucidate the differential role of otolith, semicircular canal (SSC), visual, proprioceptive, and cognitive influences on the postural stability of BVF patients. Center-of-pressure displacements were recorded by posturography under six conditions: target visibility; tonic head positions in the pitch plane; horizontal head shaking; sensory deprivation; dual task; and tandem stance. Between-group analysis revealed larger postural sway in BVF patients on eye closure; but with the eyes open, BVF did not differ from healthy controls (HCs). Head tilts and horizontal head shaking increased sway but did not differ between groups. In the dual task condition, BVF patients maintained posture indistinguishable from controls. On foam and tandem stance, postural sway was larger in BVF, even with the eyes open. The best predictor for the severity of bilateral vestibulopathy was standing on foam with eyes closed. Postural control of our BVF was indistinguishable from HCs once visual and proprioceptive feedback is provided. This distinguishes them from patients with vestibulo-cerebellar disorders or functional dizziness. It confirms previous reports and explains that postural unsteadiness of BVF patients can be missed easily if not examined by conditions of visual and/or proprioceptive deprivation. In fact, the best predictor for vestibular hypofunction (VOR gain) was examining patients standing on foam with the eyes closed. Postural sway in that condition increased with the severity of vestibular impairment but not with disease duration. In the absence of visual control, impaired otolith input destabilizes BVF with head retroflexion. Stimulating deficient SSC does not distinguish patients from controls possibly reflecting a shift of intersensory weighing toward proprioceptive-guided postural control. Accordingly, proprioceptive deprivation heavily destabilizes BVF, even when visual control is provided.

Postural Control in Bilateral Vestibular Failure: Its Relation to Visual, Proprioceptive, Vestibular, and Cognitive Input

PubMed Central

Sprenger, Andreas; Wojak, Jann F.; Jandl, Nico M.; Helmchen, Christoph

2017-01-01

Patients with bilateral vestibular failure (BVF) suffer from postural and gait unsteadiness with an increased risk of falls. The aim of this study was to elucidate the differential role of otolith, semicircular canal (SSC), visual, proprioceptive, and cognitive influences on the postural stability of BVF patients. Center-of-pressure displacements were recorded by posturography under six conditions: target visibility; tonic head positions in the pitch plane; horizontal head shaking; sensory deprivation; dual task; and tandem stance. Between-group analysis revealed larger postural sway in BVF patients on eye closure; but with the eyes open, BVF did not differ from healthy controls (HCs). Head tilts and horizontal head shaking increased sway but did not differ between groups. In the dual task condition, BVF patients maintained posture indistinguishable from controls. On foam and tandem stance, postural sway was larger in BVF, even with the eyes open. The best predictor for the severity of bilateral vestibulopathy was standing on foam with eyes closed. Postural control of our BVF was indistinguishable from HCs once visual and proprioceptive feedback is provided. This distinguishes them from patients with vestibulo-cerebellar disorders or functional dizziness. It confirms previous reports and explains that postural unsteadiness of BVF patients can be missed easily if not examined by conditions of visual and/or proprioceptive deprivation. In fact, the best predictor for vestibular hypofunction (VOR gain) was examining patients standing on foam with the eyes closed. Postural sway in that condition increased with the severity of vestibular impairment but not with disease duration. In the absence of visual control, impaired otolith input destabilizes BVF with head retroflexion. Stimulating deficient SSC does not distinguish patients from controls possibly reflecting a shift of intersensory weighing toward proprioceptive-guided postural control. Accordingly, proprioceptive deprivation heavily destabilizes BVF, even when visual control is provided. PMID:28919878

Touch-screen tablet user configurations and case-supported tilt affect head and neck flexion angles.

PubMed

Young, Justin G; Trudeau, Matthieu; Odell, Dan; Marinelli, Kim; Dennerlein, Jack T

2012-01-01

The aim of this study was to determine how head and neck postures vary when using two media tablet (slate) computers in four common user configurations. Fifteen experienced media tablet users completed a set of simulated tasks with two media tablets in four typical user configurations. The four configurations were: on the lap and held with the user's hands, on the lap and in a case, on a table and in a case, and on a table and in a case set at a high angle for watching movies. An infra-red LED marker based motion analysis system measured head/neck postures. Head and neck flexion significantly varied across the four configurations and across the two tablets tested. Head and neck flexion angles during tablet use were greater, in general, than angles previously reported for desktop and notebook computing. Postural differences between tablets were driven by case designs, which provided significantly different tilt angles, while postural differences between configurations were driven by gaze and viewing angles. Head and neck posture during tablet computing can be improved by placing the tablet higher to avoid low gaze angles (i.e. on a table rather than on the lap) and through the use of a case that provides optimal viewing angles.

Notebook computer use on a desk, lap and lap support: effects on posture, performance and comfort.

PubMed

Asundi, Krishna; Odell, Dan; Luce, Adam; Dennerlein, Jack T

2010-01-01

This study quantified postures of users working on a notebook computer situated in their lap and tested the effect of using a device designed to increase the height of the notebook when placed on the lap. A motion analysis system measured head, neck and upper extremity postures of 15 adults as they worked on a notebook computer placed on a desk (DESK), the lap (LAP) and a commercially available lapdesk (LAPDESK). Compared with the DESK, the LAP increased downwards head tilt 6 degrees and wrist extension 8 degrees . Shoulder flexion and ulnar deviation decreased 13 degrees and 9 degrees , respectively. Compared with the LAP, the LAPDESK decreased downwards head tilt 4 degrees , neck flexion 2 degrees , and wrist extension 9 degrees. Users reported less discomfort and difficulty in the DESK configuration. Use of the lapdesk improved postures compared with the lap; however, all configurations resulted in high values of wrist extension, wrist deviation and downwards head tilt. STATEMENT OF RELEVANCE: This study quantifies postures of users working with a notebook computer in typical portable configurations. A better understanding of the postures assumed during notebook computer use can improve usage guidelines to reduce the risk of musculoskeletal injuries.

Vestibular ablation and a semicircular canal prosthesis affect postural stability during head turns

PubMed Central

Thompson, Lara A.; Haburcakova, Csilla; Lewis, Richard F.

2016-01-01

In our study, we examined postural stability during head turns for two rhesus monkeys: one, single animal study contrasted normal and mild bilateral vestibular ablation and a second animal study contrasted severe bilateral vestibular ablation with and without prosthetic stimulation. The monkeys freely stood, unrestrained on a balance platform and made voluntary head turns between visual targets. To quantify each animals’ posture, motions of the head and trunk, as well as torque about the body’s center-of-mass, were measured. In the mildly ablated animal, we observed less foretrunk sway in comparison to the normal state. When the canal prosthesis provided electric stimulation to the severely ablated animal, it showed a decrease in trunk sway during head turns. Because the rhesus monkey with severe bilateral vestibular loss exhibited a decrease in trunk sway when receiving vestibular prosthetic stimulation, we propose that the prosthetic electrical stimulation partially restored head velocity information. Our results provide an indication that a semicircular canal prosthesis may be an effective way to improve postural stability in patients with severe peripheral vestibular dysfunction. PMID:27405997

Backset and cervical retraction capacity among occupants in a modern car.

PubMed

Jonsson, Bertil; Stenlund, Hans; Svensson, Mats Y; Björnstig, Ulf

2007-03-01

The horizontal distance between the back of the head and the frontal of the head restraint (backset) and rearward head movement relative to the torso (cervical retraction) were studied in different occupant postures and positions in a modern car. A stratified randomized population of 154 test subjects was studied in a Volvo V70 year model 2003 car, in driver, front passenger, and rear passenger position. In each position, the subjects adopted (i) a self-selected posture, (ii) a sagging posture, and (iii) an erect posture. Cervical retraction, backset, and vertical distance from the top of the head restraint to the occipital protuberance in the back of the head of the test subject were measured. These data were analyzed using repeated measures ANOVA and linear regression analysis with a significance level set to p < 0.05. In the self-selected posture, the average backset was 61 mm for drivers, 29 mm for front passengers, and 103 mm for rear passengers (p < 0.001). Women had lower mean backset (40 mm) than men (81 mm), particularly in the self-selected driving position. Backset was larger and cervical retraction capacity lower in the sagging posture than in the self-selected posture for occupants in all three occupant positions. Rear passengers had the largest backset values. Backset values decreased with increased age. The average cervical retraction capacity in self-selected posture was 35 mm for drivers, 30 mm for front passengers, and 33 mm for rear passengers (p < 0.001). Future design of rear-end impact protection may take these study results into account when trying to reduce backset before impact. Our results might be used for future development and use of BioRID manikins and rear-end tests in consumer rating test programs such as Euro-NCAP.

Cranio-cervical posture: a factor in the development and function of the dentofacial structures.

PubMed

Solow, Beni; Sandham, Andrew

2002-10-01

Many practitioners will recognize that subjects with a large mandibular plane inclination are characterized by an extended head posture and a forward inclined cervical column, i.e. an extended cranio-cervical posture. It is also typical that subjects with a short-face morphology often carry their heads somewhat lowered, and have a markedly backward-curved upper cervical spine, i.e. cervical lordosis. The aim of the paper is to link together the findings of a series of studies that attempt to clarify this relationship, and bring into focus cranio-cervical posture, which is a functional factor that seems to be involved in many clinical orthodontic problems. To provide a background for the article, the concept of standardized posture of the head and the cervical column is developed, and procedures for recording this posture, as well as categories of cephalometric variables that express the different postural relationships, are described. Findings that relate cranio-cervical posture to upper airway obstruction, to craniofacial morphology, and to malocclusion are surveyed, and a post-natal developmental mechanism that explains the findings and leads to further questions is discussed. Recent findings of a relationship between extended cranio-cervical posture and signs and symptoms of temporomandibular disorders further emphasize the biological importance of this functional parameter.

Proprioceptive encoding of head position in the black soldier fly, Hermetia illucens (L.) (Stratiomyidae).

PubMed

Paulk, Angelique; Gilbert, Cole

2006-10-01

Because the eyes of insects cannot be moved independently of the head, information about head posture is essential for stabilizing the visual world or providing information about the direction of gaze. We examined the external anatomy and physiological capabilities of a head posture proprioceptor, the prosternal organ (PO), located at the base of the neck in the black soldier fly, Hermetia illucens (L.) (Family: Stratiomyidae). The PO is sexually isomorphic and is composed of two fused plates of about 130 mechanosensory hairs set in asymmetrical sockets whose orientation varies across the organ. A multi-joint mechanical coupling between the head, neck membrane, and contact sclerites deflects the hairs more or less to increase or decrease their level of excitation. The PO sensory afferents project to the central nervous system (CNS) via a pair of bilateral prosternal nerves (PN) to the fused thoracic ganglia. Simultaneous recording of spiking activity in the PN and videotaping of wind-induced and voluntary head movements around all three axes of head rotation reveal that a few PN afferents are active at rest, but activity increases tonically in response to head deflections. Activity is significantly modulated by change in head angles around the pitch (+/-40 degrees ), yaw (+/-30 degrees ) and roll (more than +/-90 degrees ) axes, although the dynamic range of spiking activity differs for each axis of rotation. Prosternal nerve afferents are bilaterally excited (inhibited) by pitch down (up); excited (inhibited) by head yaw toward the ipsilateral (contralateral) side; excited by roll down toward the ipsilateral side, but little inhibited by roll toward the opposite side. Although bilateral comparison of activity in PN afferents reliably encodes head posture around a given rotational axis, from the point of view of the CNS, the problem of encoding head posture is ill-posed with three axes of rotation and only two streams of afferent information. Furthermore, when the head is rotated around more than one axis simultaneously, mechanical interactions in the neck modify the responses to postural changes around the three rotational axes, which adds further ambiguity to reliable encoding of head posture. The properties of the PO in this relatively basal fly species are compared to those of higher flies and possible mechanisms of disambiguation are discussed.

Cervical posture analysis in dental students and its correlation with temporomandibular disorder.

PubMed

Câmara-Souza, Mariana Barbosa; Figueredo, Olívia Maria Costa; Maia, Paulo Raphael Leite; Dantas, Isabelle de Sousa; Barbosa, Gustavo Augusto Seabra

2018-03-01

To evaluate the relationship between temporomandibular disorders (TMD) and craniocervical posture in the sagittal plane measured from lateral radiographs of the head. The sample was comprised of 80 randomly selected students of dentistry at the Federal University of Rio Grande do Norte. Research Diagnostic Criteria for TMD (RDC/TMD) was used to evaluate the signs and symptoms of TMD. Lateral radiographs of each individual were used to measure the position of the hyoid bone, the craniocervical angle, and the occiput-atlas distance. A chi-square test was used to evaluate the relationships between craniocervical posture measures and TMD. No relationship was found between TMD and the craniocervical posture measured by the positioning of the hyoid bone, head rotation, and the extension/flexion of the head (p > 0.05). It can be concluded, therefore, that no relationship exists between cervical posture in the sagittal plane and TMD.

Gender difference in mobile phone use and the impact of digital device exposure on neck posture.

PubMed

Guan, Xiaofei; Fan, Guoxin; Chen, Zhengqi; Zeng, Ying; Zhang, Hailong; Hu, Annan; Gu, Guangfei; Wu, Xinbo; Gu, Xin; He, Shisheng

2016-11-01

This cross-sectional study aimed to identify gender differences in the cervical postures when young adults were using mobile phones, as well as the correlations between the postures and the digital devices use (computer and mobile phone). Questionnaires regarding the habits of computer and mobile phone use were administrated to 429 subjects aged from 17 to 33 years old (19.75 ± 2.58 years old). Subjects were instructed to stand habitually and use a mobile phone as in daily life; the sagittal head and cervical postures were measured by head flexion, neck flexion angle and gaze angle. Male participants had a significantly larger head flexion angle (96.41° ± 12.23° vs. 93.57° ± 12.62°, p  =  0.018) and neck flexion angle (51.92°  ±  9.55° vs. 47.09° ± 9.45°, p  <  0.001) than females. There were significant differences in head (F  =  3.62, p  =  0.014) and neck flexion (F  =  3.99, p  =  0.009) between different amounts of computer use. Practitioner Summary: We investigated possible gender differences in head and neck postures of young adults using mobile phones, as well as the potential correlations between these postures and digital device use. We found that males displayed larger head and neck flexion angles than females, which were associated with the amount of computer use.

Cervical and shoulder postural assessment of adolescents between 15 and 17 years old and association with upper quadrant pain

PubMed Central

Ruivo, Rodrigo M.; Pezarat-Correia, Pedro; Carita, Ana I.

2014-01-01

Background: There is sparse literature that provides evidence of cervical and shoulder postural alignment of 15 to 17-year-old adolescents and that analyzes sex differences. Objectives: To characterize the postural alignment of the head and shoulder in the sagittal plane of 15 to 17-year-old Portuguese adolescents in natural erect standing and explore the relationships between three postural angles and presence of neck and shoulder pain. Method: This cross-sectional study was conducted in two secondary schools in Portugal. 275 adolescent students (153 females and 122 males) aged 15 to 17 were evaluated. Sagittal head, cervical, and shoulder angles were measured with photogrammetry and PAS software. The American Shoulder and Elbow Surgeons Shoulder Assessment (ASES) was used to assess shoulder pain, whereas neck pain was self-reported with a single question. Results: Mean values of sagittal head, cervical, and shoulder angles were 17.2±5.7, 47.4±5.2, and 51.4±8.5º, respectively. 68% of the participants revealed protraction of the head, whereas 58% of them had protraction of the shoulder. The boys showed a significantly higher mean cervical angle, and adolescents with neck pain revealed lower mean cervical angle than adolescents without neck pain. 53% of the girls self-reported regular neck pain, contrasting with 19% of the boys. Conclusions: This data shows that forward head and protracted shoulder are common postural disorders in adolescents, especially in girls. Neck pain is prevalent in adolescents, especially girls, and it is associated with forward head posture. PMID:25054381

Cervical and shoulder postural assessment of adolescents between 15 and 17 years old and association with upper quadrant pain.

PubMed

Ruivo, Rodrigo M; Pezarat-Correia, Pedro; Carita, Ana I

2014-01-01

There is sparse literature that provides evidence of cervical and shoulder postural alignment of 15 to 17-year-old adolescents and that analyzes sex differences. To characterize the postural alignment of the head and shoulder in the sagittal plane of 15 to 17-year-old Portuguese adolescents in natural erect standing and explore the relationships between three postural angles and presence of neck and shoulder pain. This cross-sectional study was conducted in two secondary schools in Portugal. 275 adolescent students (153 females and 122 males) aged 15 to 17 were evaluated. Sagittal head, cervical, and shoulder angles were measured with photogrammetry and PAS software. The American Shoulder and Elbow Surgeons Shoulder Assessment (ASES) was used to assess shoulder pain, whereas neck pain was self-reported with a single question. Mean values of sagittal head, cervical, and shoulder angles were 17.2±5.7, 47.4±5.2, and 51.4±8.5º, respectively. 68% of the participants revealed protraction of the head, whereas 58% of them had protraction of the shoulder. The boys showed a significantly higher mean cervical angle, and adolescents with neck pain revealed lower mean cervical angle than adolescents without neck pain. 53% of the girls self-reported regular neck pain, contrasting with 19% of the boys. This data shows that forward head and protracted shoulder are common postural disorders in adolescents, especially in girls. Neck pain is prevalent in adolescents, especially girls, and it is associated with forward head posture.

Breathing pattern and head posture: changes in craniocervical angles.

PubMed

Sabatucci, A; Raffaeli, F; Mastrovincenzo, M; Luchetta, A; Giannone, A; Ciavarella, D

2015-04-01

The aim of this study was to observe the influence of oral breathing on head posture and to establish possible postural changes observing the variation of craniocervical angles NSL/OPT and NSL/CVT between oral breathing subjects and physiological breathing subjects. A cross-sectional study was conducted. The sample included 115 subject, 56 boys and 59 girls, 5-22-year-old. Among these, 80 were classified as oral breathers and 35 as physiological breathers. The diagnosis of oral breathing was carried out thanks to characteristic signs and symptoms evaluated on clinical examination, the analysis of characteristic X-ray images, ENT examination with active anterior rhinomanometric (AAR) test. The structural and postural analysis was carried out, calculating the craniofacial angles NSL/OPT and NSL/CVT. Both NSL/OPT and NSL/CVT appear to be significantly greater to those observed in physiological breathing patients. This means that patients who tend to breathe through the mouth rather than exclusively through the nose show a reduction of cervical lordosis and a proinclination of the head. Our study confirms that the oral breathing modifies head position. The significant increase of the craniocervical angles NSL/OPT and NSL/CVT in patients with this altered breathing pattern suggests an elevation of the head and a greater extension of the head compared with the cervical spine. So, to correct the breathing pattern early, either during childhood or during adolescence, can lead to a progressive normalization of craniofacial morphology and head posture.

Head posture and cervicovertebral and craniofacial morphology in patients with craniomandibular dysfunction.

PubMed

Huggare, J A; Raustia, A M

1992-07-01

A relationship between particular characteristics of dental occlusion and craniomandibular disorders (CMD) has been reported, while less attention has been focused on the possible effect of dysfunction of the masticatory system on head posture or cervicovertebral and craniofacial morphology. Natural head position roentgen-cephalograms of 16 young adults with complete dentition taken before and after stomatognathic treatment displayed an extended head posture, smaller size of the uppermost cervical vertebrae, decreased posterior to anterior face height ratio, and a flattened cranial base as compared with age- and sex-matched healthy controls. The lordosis of the cervical spine straightened after stomatognathic treatment. The results are an indication of the close interrelationship between the masticatory muscle system and the muscles supporting the head, and lead to speculation on the principles of treating craniomandibular disorders.

Nintendo Wii remote controllers for head posture measurement: accuracy, validity, and reliability of the infrared optical head tracker.

PubMed

Kim, Jongshin; Nam, Kyoung Won; Jang, Ik Gyu; Yang, Hee Kyung; Kim, Kwang Gi; Hwang, Jeong-Min

2012-03-15

To evaluate the accuracy, validity, and reliability of a newly developed infrared optical head tracker (IOHT) using Nintendo Wii remote controllers (WiiMote; Nintendo Co. Ltd., Kyoto, Japan) for measurement of the angle of head posture. The IOHT consists of two infrared (IR) receivers (WiiMote) that are fixed to a mechanical frame and connected to a monitoring computer via a Bluetooth communication channel and an IR beacon that consists of four IR light-emitting diodes (LEDs). With the use of the Cervical Range of Motion (CROM; Performance Attainment Associates, St. Paul, MN) as a reference, one- and three-dimensional (1- and 3-D) head postures of 20 normal adult subjects (20-37 years of age; 9 women and 11 men) were recorded with the IOHT. In comparison with the data from the CROM, the IOHT-derived results showed high consistency. The measurements of 1- and 3-D positions of the human head with the IOHT were very close to those of the CROM. The correlation coefficients of 1- and 3-D positions between the IOHT and the CROM were more than 0.99 and 0.96 (P < 0.05, Pearson's correlation test), respectively. Reliability tests of the IOHT for the normal adult subjects for 1- and 3-D positions of the human head had 95% limits of agreement angles of approximately ±4.5° and ±8.0°, respectively. The IOHT showed strong concordance with the CROM and relatively good test-retest reliability, thus proving its validity and reliability as a head-posture-measuring device. Considering its high performance, ease of use, and low cost, the IOHT has the potential to be widely used as a head-posture-measuring device in clinical practice.

Postural Instability Induced by Visual Motion Stimuli in Patients With Vestibular Migraine

PubMed Central

Lim, Yong-Hyun; Kim, Ji-Soo; Lee, Ho-Won; Kim, Sung-Hee

2018-01-01

Patients with vestibular migraine are susceptible to motion sickness. This study aimed to determine whether the severity of posture instability is related to the susceptibility to motion sickness. We used a visual motion paradigm with two conditions of the stimulated retinal field and the head posture to quantify postural stability while maintaining a static stance in 18 patients with vestibular migraine and in 13 age-matched healthy subjects. Three parameters of postural stability showed differences between VM patients and controls: RMS velocity (0.34 ± 0.02 cm/s vs. 0.28 ± 0.02 cm/s), RMS acceleration (8.94 ± 0.74 cm/s2 vs. 6.69 ± 0.87 cm/s2), and sway area (1.77 ± 0.22 cm2 vs. 1.04 ± 0.25 cm2). Patients with vestibular migraine showed marked postural instability of the head and neck when visual stimuli were presented in the retinal periphery. The pseudo-Coriolis effect induced by head roll tilt was not responsible for the main differences in postural instability between patients and controls. Patients with vestibular migraine showed a higher visual dependency and low stability of the postural control system when maintaining quiet standing, which may be related to susceptibility to motion sickness. PMID:29930534

Postural Instability Induced by Visual Motion Stimuli in Patients With Vestibular Migraine.

PubMed

Lim, Yong-Hyun; Kim, Ji-Soo; Lee, Ho-Won; Kim, Sung-Hee

2018-01-01

Patients with vestibular migraine are susceptible to motion sickness. This study aimed to determine whether the severity of posture instability is related to the susceptibility to motion sickness. We used a visual motion paradigm with two conditions of the stimulated retinal field and the head posture to quantify postural stability while maintaining a static stance in 18 patients with vestibular migraine and in 13 age-matched healthy subjects. Three parameters of postural stability showed differences between VM patients and controls: RMS velocity (0.34 ± 0.02 cm/s vs. 0.28 ± 0.02 cm/s), RMS acceleration (8.94 ± 0.74 cm/s 2 vs. 6.69 ± 0.87 cm/s 2 ), and sway area (1.77 ± 0.22 cm 2 vs. 1.04 ± 0.25 cm 2 ). Patients with vestibular migraine showed marked postural instability of the head and neck when visual stimuli were presented in the retinal periphery. The pseudo-Coriolis effect induced by head roll tilt was not responsible for the main differences in postural instability between patients and controls. Patients with vestibular migraine showed a higher visual dependency and low stability of the postural control system when maintaining quiet standing, which may be related to susceptibility to motion sickness.

Postural compensation for vestibular loss and implications for rehabilitation.

PubMed

Horak, Fay B

2010-01-01

This chapter summarizes the role of the vestibular system in postural control so that specific and effective rehabilitation can be designed that facilitates compensation for loss of vestibular function. Patients with bilateral or unilateral loss of peripheral vestibular function are exposed to surface perturbations to quantify automatic postural responses. Studies also evaluated the effects of audio- and vibrotactile-biofeedback to improve stability in stance and gait. The most important role of vestibular information for postural control is to control orientation of the head and trunk in space with respect to gravitoinertial forces, particularly when balancing on unstable surfaces. Vestibular sensory references are particularly important for postural control at high frequencies and velocities of self-motion, to reduce trunk drift and variability, to provide an external reference frame for the trunk and head in space; and to uncouple coordination of the trunk from the legs and the head-in-space from the body CoM. The goal of balance rehabilitation for patients with vestibular loss is to help patients 1) use remaining vestibular function, 2) depend upon surface somatosensory information as their primary postural sensory system, 3) learn to use stable visual references, and 4) identify efficient and effective postural movement strategies.

Defective balancing ability and hyperactivity in the CLX (circling behavior linked to the X-chromosome) mutant rat.

PubMed

Fuji, Jun-ichiro; Tanabe, Hiroyuki; Fukuda, Ryo; Ooshima, Yojiro

2003-12-01

We have reported that the recently described circling behavior rat (CLX) is a hereditary mutant controlled by a single sex-linked recessive gene (gene symbol: clx). This mutant shows intermittent circle walking and/or running and head tossing with the neck twisted. The abnormal behavior begins to appear around weaning and continues throughout life. In the present study, behavioral tests were performed during the suckling and post-weaning periods and when the rats reached maturity, and the following peculiar abnormalities were revealed: (1) in the righting reflex test, the CLX young show a tendency to take a longer time to revert to normal posture; (2) in the negative geotaxis test, they had difficulty moving upward at 12 days of age; (3) in the air righting reflex test, they frequently fell on their backs or shoulders even after weaning; (4) almost none of the CLX rats showed nystagmus, which is invariably observed in normal rats after rotating stimulation, at 20 weeks of age; and (5) they showed hyperactivity in the open field test at the age of 5 or 6 weeks and a higher degree of locomotor activity in the home cage at the age of 7 and 15 weeks. These results suggest that CLX mutant rats may have some defect in vestibular function (balance sense) or abnormalities in an area of the central nervous system responsible for posture control, e.g., in the dopaminergic or GABAergic neurons.

Postural control and head stability during natural gaze behaviour in 6- to 12-year-old children.

PubMed

Schärli, A M; van de Langenberg, R; Murer, K; Müller, R M

2013-06-01

We investigated how the influence of natural exploratory gaze behaviour on postural control develops from childhood into adulthood. In a cross-sectional design, we compared four age groups: 6-, 9-, 12-year-olds and young adults. Two experimental trials were performed: quiet stance with a fixed gaze (fixed) and quiet stance with natural exploratory gaze behaviour (exploratory). The latter was elicited by having participants watch an animated short film on a large screen in front of them. 3D head rotations in space and centre of pressure (COP) excursions on the ground plane were measured. Across conditions, both head rotation and COP displacement decreased with increasing age. Head movement was greater in the exploratory condition in all age groups. In all children-but not in adults-COP displacement was markedly greater in the exploratory condition. Bivariate correlations across groups showed highly significant positive correlations between COP displacement in ML direction and head rotation in yaw, roll, and pitch in both conditions. The regularity of COP displacements did not show a clear developmental trend, which indicates that COP dynamics were qualitatively similar across age groups. Together, the results suggest that the contribution of head movement to eye-head saccades decreases with age and that head instability-in part resulting from such gaze-related head movements-is an important limiting factor in children's postural control. The lack of head stabilisation might particularly affect children in everyday activities in which both postural control and visual exploration are required.

Investigation of the Differential Contributions of Superficial and Deep Muscles on Cervical Spinal Loads with Changing Head Postures

PubMed Central

Cheng, Chih-Hsiu; Chien, Andy; Hsu, Wei-Li; Chen, Carl Pai-Chu; Cheng, Hsin-Yi Kathy

2016-01-01

Cervical spinal loads are predominately influenced by activities of cervical muscles. However, the coordination between deep and superficial muscles and their influence on the spinal loads is not well understood. This study aims to document the changes of cervical spinal loads and the differential contributions of superficial and deep muscles with varying head postures. Electromyography (EMG) of cervical muscles from seventeen healthy adults were measured during maximal isometric exertions for lateral flexion (at 10°, 20° and terminal position) as well as flexion/extension (at 10°, 20°, 30°, and terminal position) neck postures. An EMG-assisted optimization approach was used to estimate the muscle forces and subsequent spinal loads. The results showed that compressive and anterior-posterior shear loads increased significantly with neck flexion. In particular, deep muscle forces increased significantly with increasing flexion. It was also determined that in all different static head postures, the deep muscle forces were greater than those of the superficial muscle forces, however, such pattern was reversed during peak efforts where greater superficial muscle forces were identified with increasing angle of inclination. In summary, the identification of significantly increased spinal loads associated with increased deep muscle activation during flexion postures, implies higher risks in predisposing the neck to occupationally related disorders. The results also explicitly supported that deep muscles play a greater role in maintaining stable head postures where superficial muscles are responsible for peak exertions and reinforcing the spinal stability at terminal head postures. This study provided quantitative data of normal cervical spinal loads and revealed motor control strategies in coordinating the superficial and deep muscles during physical tasks. PMID:26938773

Investigation of the Differential Contributions of Superficial and Deep Muscles on Cervical Spinal Loads with Changing Head Postures.

PubMed

Cheng, Chih-Hsiu; Chien, Andy; Hsu, Wei-Li; Chen, Carl Pai-Chu; Cheng, Hsin-Yi Kathy

2016-01-01

Cervical spinal loads are predominately influenced by activities of cervical muscles. However, the coordination between deep and superficial muscles and their influence on the spinal loads is not well understood. This study aims to document the changes of cervical spinal loads and the differential contributions of superficial and deep muscles with varying head postures. Electromyography (EMG) of cervical muscles from seventeen healthy adults were measured during maximal isometric exertions for lateral flexion (at 10°, 20° and terminal position) as well as flexion/extension (at 10°, 20°, 30°, and terminal position) neck postures. An EMG-assisted optimization approach was used to estimate the muscle forces and subsequent spinal loads. The results showed that compressive and anterior-posterior shear loads increased significantly with neck flexion. In particular, deep muscle forces increased significantly with increasing flexion. It was also determined that in all different static head postures, the deep muscle forces were greater than those of the superficial muscle forces, however, such pattern was reversed during peak efforts where greater superficial muscle forces were identified with increasing angle of inclination. In summary, the identification of significantly increased spinal loads associated with increased deep muscle activation during flexion postures, implies higher risks in predisposing the neck to occupationally related disorders. The results also explicitly supported that deep muscles play a greater role in maintaining stable head postures where superficial muscles are responsible for peak exertions and reinforcing the spinal stability at terminal head postures. This study provided quantitative data of normal cervical spinal loads and revealed motor control strategies in coordinating the superficial and deep muscles during physical tasks.

Assisting people with multiple disabilities actively correct abnormal standing posture with a Nintendo Wii balance board through controlling environmental stimulation.

PubMed

Shih, Ching-Hsiang; Shih, Ching-Tien; Chu, Chiung-Ling

2010-01-01

The latest researches adopted software technology turning the Nintendo Wii Balance Board into a high performance change of standing posture (CSP) detector, and assessed whether two persons with multiple disabilities would be able to control environmental stimulation using body swing (changing standing posture). This study extends Wii Balance Board functionality for standing posture correction (i.e., actively adjust abnormal standing posture) to assessed whether two persons with multiple disabilities would be able to actively correct their standing posture by controlling their favorite stimulation on/off using a Wii Balance Board with a newly developed standing posture correcting program (SPCP). The study was performed according to an ABAB design, in which A represented baseline and B represented intervention phases. Data showed that both participants significantly increased time duration of maintaining correct standing posture (TDMCSP) to activate the control system to produce environmental stimulation during the intervention phases. Practical and developmental implications of the findings were discussed.

A Clinical Study to Examine the Effect of Complete Denture on Head Posture/Craniovertical Angle.

PubMed

Khare, Amit; Nandeeshwar, D B; Sangur, Rajashekar; Makkar, Sumit; Khare, Pooja; Chitumalla, Rajkiran; Prasad, Renuka

2016-04-01

Edentulous patients show some significant changes in ridge relationship caused by resorption of alveolar ridge. The changes are characterized by an upward rotation of mandible, increase in mandibular prognathism that ultimately results in change of natural head posture. This clinical study was planned to know the effect of complete denture on head posture in different age groups of Indian completely edentulous population, after placement of complete denture at various time intervals. The sample consisted of completely edentulous patients without previous experience of the dentures. They were divided into 2 age groups: Group A (45-60) and Group B (61-75). During placement of complete denture craniovertical angle was measured with the help of custom made ruler protector device. Readings were taken before denture placement, immediately after denture placement, 30 minutes, 24 hours and 30 days after dentures placement. The results of this study indicated that in most of the patients (90%) despite their age, change in head posture (extension) occurred immediately after the denture placement. Thereafter reading remains same for measurement at 30 minutes and 24 hours of denture placement. However after 30 days, observation revealed that all the patients showed reduced craniovertical angle (flexion). Even though the values of craniovertical angle remain higher than its baseline in both groups, significant changes were noticed only in Group A. Findings revealed that head posture was significantly altered by the placement of dentures in completely edentulous patients. Within the time interval of 30 minutes and 24 hours extension of head posture remained constant with slight variation. Although after 30 days, changes remained significant for group 'A', but no significant changes were observed in the subjects of group 'B'.

Effects of suboccipital release with craniocervical flexion exercise on craniocervical alignment and extrinsic cervical muscle activity in subjects with forward head posture.

PubMed

Kim, Bo-Been; Lee, Ji-Hyun; Jeong, Hyo-Jung; Cynn, Heon-Seock

2016-10-01

Forward head posture is a head-on-trunk malalignment, which results in musculoskeletal dysfunction and neck pain. To improve forward head posture, both the craniocervical flexion exercise and the suboccipital release technique have been used. The purpose of this study was to compare the immediate effects of craniocervical flexion exercise and suboccipital release combined with craniocervical flexion exercise on craniovertebral angle, cervical flexion and extension range of motion, and the muscle activities of the sternocleidomastoid, anterior scalene, and splenius capitis during craniocervical flexion exercise in subjects with forward head posture. In total, 19 subjects (7 males, 12 females) with forward head posture were recruited using G-power software. Each subject performed craniocervical flexion exercise and suboccipital release combined with craniocervical flexion exercise in random order. After one intervention was performed, the subject took a 20min wash out period to minimize any carry-over effect between interventions. Craniovertebral angle, cervical flexion and extension range of motion, and the muscle activities of the sternocleidomastoid, anterior scalene, and splenius capitis were measured. A one-way, repeated-measures ANOVA was used to assess differences between the effects of the craniocervical flexion exercise and suboccipital release combined with craniocervical flexion exercise interventions in the same group. Craniovertebral angle (p<0.05), cervical flexion range of motion (p<0.05), and cervical extension range of motion (p<0.001) were significantly greater after suboccipital release combined with craniocervical flexion exercise compared to craniocervical flexion exercise alone. The muscle activities of the sternocleidomastoid, anterior scalene, and splenius capitis were significantly lower during suboccipital release combined with craniocervical flexion exercise than during craniocervical flexion exercise alone across all craniocervical flexion exercise phases except the first (all p<0.05). The addition of suboccipital release to craniocervical flexion exercise provided superior benefits relative to craniocervical flexion exercise alone as an intervention for subjects with forward head posture. Copyright © 2016 Elsevier Ltd. All rights reserved.

A computerized photographic method to evaluate changes in head posture and scapular position following rapid palatal expansion: a pilot study.

PubMed

Cerruto, Carmen; Di Vece, Luca; Doldo, Tiziana; Giovannetti, Agostino; Polimeni, Antonella; Goracci, Cecilia

2012-01-01

To assess the applicability of a computerized method to measure on digital photographs the changes in head and scapular posture following rapid palatal expansion (RPE) treatment. Randomized controlled trial. Twenty-three children (age 9.2 +/- 70.88 years) diagnosed with maxillary constriction were randomly divided into two groups: 1. Study group (n = 12): patients receiving RPE treatment; 2. Untreated controls (n = 11). Postural measurements were taken on frontal, lateral, and dorsal views of each subject. In the study group measurements were taken at T0 (the day orthodontic records were taken), T1 (end of RPE active phase), and T2 (RPE removal). In controls the same observations were conducted at T0 and T1(98.18 +/- 36.01 days after T0). Measurements were statistically analyzed (Intraclass Correlation Coefficient, t-tests, Signed Rank test, One-Way Repeated Measures Analysis of Variance, Tukey test; p < 0.05). In the study group a significant reduction in forward head posture (FHP) occurred between T0 and T1. Forward shoulder posture (FSP) decreased significantly between T1 and T2. At T1 treated patients exhibited significantly lower values of the measurements indicating FHP and FSP than controls. Changes in head and scapular posture following RPE treatment can be documented with computerized measurements on digital photographs.

Comparison of Postural Recovery Following Short and Long Duration Spaceflights

NASA Technical Reports Server (NTRS)

Wood, S. J.; Fiedler, J.; Taylor, L. C.; Kozlovskaya, I.; Black, F. O.; Paloski, W. H.

2010-01-01

INTRODUCTION: Post-flight postural ataxia reflects adaptive changes to vestibulo-spinal reflexes and control strategies adopted for movement in weightlessness. Quantitative measures obtained during computerized dynamic posturography (CDP) from US and Russian programs provide insight into the effect of spaceflight duration in terms of both the initial decrements and recovery of postural stability. METHODS: CDP was obtained on 117 crewmembers following Shuttle flights lasting 4-17 days, and on 64 crewmembers following long-duration missions lasting 48-380 days. Although the number and timing of sessions varied, the goal was to characterize postural recovery pooling similar measures from different research and flight medicine programs. This report focuses on eyes closed, head erect conditions with either a fixed or sway-referenced base of support. A smaller subset of subjects repeated the sway-referenced condition while making pitch head movements (+/- 20deg at 0.33Hz). Equilibrium scores were derived from peak-to-peak anterior-posterior sway. Fall probability was modeled using Bayesian statistical methods to estimate parameters of a logit function. RESULTS: The standard Romberg condition was the least sensitive. Longer duration flights led to larger decrements in stability with sway-reference support during the first 1-2 days, although the timecourse of recovery was similar across flight duration with head erect. Head movements led to increased incidence of falls during the first week, with a significantly longer recovery following long duration flights. CONCLUSIONS: The diagnostic assessment of postural instability, and differences in the timecourse of postural recovery between short and long flight durations, are more pronounced during unstable support conditions requiring active head movements.

A link-segment model of upright human posture for analysis of head-trunk coordination

NASA Technical Reports Server (NTRS)

Nicholas, S. C.; Doxey-Gasway, D. D.; Paloski, W. H.

1998-01-01

Sensory-motor control of upright human posture may be organized in a top-down fashion such that certain head-trunk coordination strategies are employed to optimize visual and/or vestibular sensory inputs. Previous quantitative models of the biomechanics of human posture control have examined the simple case of ankle sway strategy, in which an inverted pendulum model is used, and the somewhat more complicated case of hip sway strategy, in which multisegment, articulated models are used. While these models can be used to quantify the gross dynamics of posture control, they are not sufficiently detailed to analyze head-trunk coordination strategies that may be crucial to understanding its underlying mechanisms. In this paper, we present a biomechanical model of upright human posture that extends an existing four mass, sagittal plane, link-segment model to a five mass model including an independent head link. The new model was developed to analyze segmental body movements during dynamic posturography experiments in order to study head-trunk coordination strategies and their influence on sensory inputs to balance control. It was designed specifically to analyze data collected on the EquiTest (NeuroCom International, Clackamas, OR) computerized dynamic posturography system, where the task of maintaining postural equilibrium may be challenged under conditions in which the visual surround, support surface, or both are in motion. The performance of the model was tested by comparing its estimated ground reaction forces to those measured directly by support surface force transducers. We conclude that this model will be a valuable analytical tool in the search for mechanisms of balance control.

Comparison of cervical muscle thickness between asymptomatic women with and without forward head posture.

PubMed

Bokaee, Fateme; Rezasoltani, Asghar; Manshadi, Farideh D; Naimi, Sedigheh S; Baghban, Alireza A; Azimi, Hadi

Forward head posture (FHP) is a forward positioning of the head relative to the trunk in the sagittal plane. This posture is one of the most prevalent poor postures in patients with head and neck pain. Rehabilitative Ultrasound Imaging (RUSI) is a reliable method to objectively evaluate muscle thickness and function. To compare thickness of cervical muscles that control both head and neck posture between asymptomatic women with and without FHP. Seventy asymptomatic women aged between 20 and 40 years, with and without FHP (35 in each group), participated in the study. The thickness of the cervical muscles (rectus capitis posterior - RCP, oblique capitis superior - OCS, semispinalis capitis - SSC, sternocleidomastoid - SCM, and longus coli - LCo) was measured using RUSI and the data was compared between the two groups. The comparison of cervical muscle thickness between women with and without FHP revealed significant difference only with regard to the muscle thickness of the SCM muscle (mean difference: 0.7mm, 95% confidence interval of the difference: 0.14, 1.26mm, p value: 0.014). The thickness of this muscle was greater in women with FHP. Tonic contraction of the SCM muscle can lead to greater thickness of this muscle in subjects with FHP. Copyright © 2017 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier Editora Ltda. All rights reserved.

Changes in posture through the use of simple inclines with notebook computers placed on a standard desk.

PubMed

Asundi, Krishna; Odell, Dan; Luce, Adam; Dennerlein, Jack T

2012-03-01

This study evaluated the use of simple inclines as a portable peripheral for improving head and neck postures during notebook computer use on tables in portable environments such as hotel rooms, cafés, and airport lounges. A 3D motion analysis system measured head, neck and right upper extremity postures of 15 participants as they completed a 10 min computer task in six different configurations, all on a fixed height desk: no-incline, 12° incline, 25° incline, no-incline with external mouse, 25° incline with an external mouse, and a commercially available riser with external mouse and keyboard. After completion of the task, subjects rated the configuration for comfort and ease of use and indicated perceived discomfort in several body segments. Compared to the no-incline configuration, use of the 12° incline reduced forward head tilt and neck flexion while increasing wrist extension. The 25° incline further reduced head tilt and neck flexion while further increasing wrist extension. The 25° incline received the lowest comfort and ease of use ratings and the highest perceived discomfort score. For portable, temporary computing environments where internal input devices are used, users may find improved head and neck postures with acceptable wrist extension postures with the utilization of a 12° incline. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

The influence of cranio-cervical posture on maximal mouth opening and pressure pain threshold in patients with myofascial temporomandibular pain disorders.

PubMed

La Touche, Roy; París-Alemany, Alba; von Piekartz, Harry; Mannheimer, Jeffrey S; Fernández-Carnero, Josue; Rocabado, Mariano

2011-01-01

The aim of this study was to assess the influence of cranio-cervical posture on the maximal mouth opening (MMO) and pressure pain threshold (PPT) in patients with myofascial temporomandibular pain disorders. A total of 29 patients (19 females and 10 males) with myofascial temporomandibular pain disorders, aged 19 to 59 years participated in the study (mean years±SD; 34.69±10.83 y). MMO and the PPT (on the right side) of patients in neutral, retracted, and forward head postures were measured. A 1-way repeated measures analysis of variance followed by 3 pair-wise comparisons were used to determine differences. Comparisons indicated significant differences in PPT at 3 points within the trigeminal innervated musculature [masseter (M1 and M2) and anterior temporalis (T1)] among the 3 head postures [M1 (F=117.78; P<0.001), M2 (F=129.04; P<0.001), and T1 (F=195.44; P<0.001)]. There were also significant differences in MMO among the 3 head postures (F=208.06; P<0.001). The intrarater reliability on a given day-to-day basis was good with the interclass correlation coefficient ranging from 0.89 to 0.94 and 0.92 to 0.94 for PPT and MMO, respectively, among the different head postures. The results of this study shows that the experimental induction of different cranio-cervical postures influences the MMO and PPT values of the temporomandibular joint and muscles of mastication that receive motor and sensory innervation by the trigeminal nerve. Our results provide data that supports the biomechanical relationship between the cranio-cervical region and the dynamics of the temporomandibular joint, as well as trigeminal nociceptive processing in different cranio-cervical postures.

Change in head posture and character of nystagmus in a patient with neurological upbeat nystagmus.

PubMed

Gonzalez, Caleb; Seth, Rajeev K; Ramos-Esteban, Jerome C

2007-01-01

To report a case of a patient with chin-up head posture and presumed congenital toxoplasmosis chorioretinal scars, who had a change in the character of the nystagmus and therefore the head posture following treatment for a neurological upbeat nystagmus. A 5 month old female presented with a chin up head posture and upbeat nystagmus. Magnetic resonance imaging of the brain revealed an arachnoid cyst in the area of the pineal gland. Nine months after cyst-peritoneal shunt surgery, the upbeat nystagmus was dampened but change in character to a rotary nystagmus worse on the left gaze. The patient had assumed a left face turn, shifting the null point from the vertical to the horizontal plane. The left face turn was successfully corrected at age eight years with a Kestenbaum procedure. This case emphasizes the possibility of having two distinct types of nystagmus associated with two etiologies. In this case, an acquired upbeat nystagmus secondary to an arachnoid cyst, and a congenital left rotary nystagmus from the chorioretinal scars. Furthermore, there can be a change in head position and character of nystagmus after treating the cause of the central motility disorder, thereby affecting the choice and timing of surgical intervention to correct the head positioning.

Standard (head-down tilt) versus modified (without head-down tilt) postural drainage in infants and young children with cystic fibrosis.

PubMed

Freitas, Diana A; Chaves, Gabriela Ss; Santino, Thayla A; Ribeiro, Cibele Td; Dias, Fernando Al; Guerra, Ricardo O; Mendonça, Karla Mpp

2018-03-09

Postural drainage is used primarily in infants with cystic fibrosis from diagnosis up to the moment when they are mature enough to actively participate in self-administered treatments. However, there is a risk of gastroesophageal reflux associated with this technique.This is an update of a review published in 2015. To compare the effects of standard postural drainage (15º to 45º head-down tilt) with modified postural drainage (15º to 30º head-up tilt) with regard to gastroesophageal reflux in infants and young children up to six years old with cystic fibrosis in terms of safety and efficacy. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Cystic Fibrosis Trials Register. We also searched the reference lists of relevant articles and reviews. Additional searches were conducted on ClinicalTrials.gov and on the WHO International Clinical Trials Registry Platform for any planned, ongoing and unpublished studies.The date of the most recent literature searches: 19 June 2017. We included randomised controlled studies that compared two postural drainage regimens (standard and modified postural drainage) with regard to gastroesophageal reflux in infants and young children (up to and including six years old) with cystic fibrosis. We used standard methodological procedures expected by Cochrane. Two review authors independently identified studies for inclusion, extracted outcome data and assessed risk of bias. We resolved disagreements by consensus or by involving a third review author. We contacted study authors to obtain missing or additional information. The quality of the evidence was assessed using GRADE. Two studies, involving a total of 40 participants, were eligible for inclusion in the review. We included no new studies in the 2018 update. The included studies were different in terms of the age of participants, the angle of tilt, the reported outcomes, the number of sessions and the study duration. The following outcomes were measured: appearance or exacerbation of gastroesophageal reflux episodes; percentage of peripheral oxygen saturation; number of exacerbations of upper respiratory tract symptoms; number of days on antibiotics for acute exacerbations; chest X-ray scores; and pulmonary function tests. One study reported that postural drainage with a 20° head-down position did not appear to exacerbate gastroesophageal reflux. However, the majority of the reflux episodes in this study reached the upper oesophagus (moderate-quality evidence). The second included study reported that modified postural drainage (30° head-up tilt) was associated with fewer number of gastroesophageal reflux episodes and fewer respiratory complications than standard postural drainage (30° head-down tilt) (moderate-quality evidence). The included studies had an overall low risk of bias. One included study was funded by the Sydney Children's Hospital Foundation and the other by the Royal Children's Hospital Research Foundation and Physiotherapy Research Foundation of Australia. Data were not able to be pooled by meta-analysis due to differences in the statistical presentation of the data. The limited evidence regarding the comparison between the two regimens of postural drainage is still weak due to the small number of included studies, the small number of participants assessed, the inability to perform any meta-analyses and some methodological issues with the studies. However, it may be inferred that the use of a postural regimen with a 30° head-up tilt is associated with a lower number of gastroesophageal reflux episodes and fewer respiratory complications in the long term. The 20° head-down postural drainage position was not found to be significantly different from the 20° head-up tilt modified position. Nevertheless, the fact that the majority of reflux episodes reached the upper oesophagus should make physiotherapists carefully consider their treatment strategy. We do not envisage that there will be any new trials undertaken that will affect the conclusions of this review; therefore, we do not plan to update this review.

Disorders of Upper Limb Movements in Ataxia-Telangiectasia

PubMed Central

Shaikh, Aasef G.; Zee, David S.; Mandir, Allen S.; Lederman, Howard M.; Crawford, Thomas O.

2013-01-01

Ataxia-telangiectasia is known for cerebellar degeneration, but clinical descriptions of abnormal tone, posture, and movements suggest involvement of the network between cerebellum and basal ganglia. We quantitatively assessed the nature of upper-limb movement disorders in ataxia-telangiectasia. We used a three-axis accelerometer to assess the natural history and severity of abnormal upper-limb movements in 80 ataxia-telangiectasia and 19 healthy subjects. Recordings were made during goal-directed movements of upper limb (kinetic task), while arms were outstretched (postural task), and at rest. Almost all ataxia-telangiectasia subjects (79/80) had abnormal involuntary movements, such as rhythmic oscillations (tremor), slow drifts (dystonia or athetosis), and isolated rapid movements (dystonic jerks or myoclonus). All patients with involuntary movements had both kinetic and postural tremor, while 48 (61%) also had resting tremor. The tremor was present in transient episodes lasting several seconds during two-minute recording sessions of all three conditions. Percent time during which episodic tremor was present was greater for postural and kinetic tasks compared to rest. Resting tremor had higher frequency but smaller amplitude than postural and kinetic tremor. Rapid non-rhythmic movements were minimal during rest, but were triggered during sustained arm postures and goal directed arm movements suggesting they are best considered a form of dystonic jerks or action myoclonus. Advancing age did not correlate with the severity of involuntary limb movements. Abnormal upper-limb movements in ataxia-telangiectasia feature classic cerebellar impairment, but also suggest involvement of the network between the cerebellum and basal ganglia. PMID:23826191

Disorders of Upper Limb Movements in Ataxia-Telangiectasia.

PubMed

Shaikh, Aasef G; Zee, David S; Mandir, Allen S; Lederman, Howard M; Crawford, Thomas O

2013-01-01

Ataxia-telangiectasia is known for cerebellar degeneration, but clinical descriptions of abnormal tone, posture, and movements suggest involvement of the network between cerebellum and basal ganglia. We quantitatively assessed the nature of upper-limb movement disorders in ataxia-telangiectasia. We used a three-axis accelerometer to assess the natural history and severity of abnormal upper-limb movements in 80 ataxia-telangiectasia and 19 healthy subjects. Recordings were made during goal-directed movements of upper limb (kinetic task), while arms were outstretched (postural task), and at rest. Almost all ataxia-telangiectasia subjects (79/80) had abnormal involuntary movements, such as rhythmic oscillations (tremor), slow drifts (dystonia or athetosis), and isolated rapid movements (dystonic jerks or myoclonus). All patients with involuntary movements had both kinetic and postural tremor, while 48 (61%) also had resting tremor. The tremor was present in transient episodes lasting several seconds during two-minute recording sessions of all three conditions. Percent time during which episodic tremor was present was greater for postural and kinetic tasks compared to rest. Resting tremor had higher frequency but smaller amplitude than postural and kinetic tremor. Rapid non-rhythmic movements were minimal during rest, but were triggered during sustained arm postures and goal directed arm movements suggesting they are best considered a form of dystonic jerks or action myoclonus. Advancing age did not correlate with the severity of involuntary limb movements. Abnormal upper-limb movements in ataxia-telangiectasia feature classic cerebellar impairment, but also suggest involvement of the network between the cerebellum and basal ganglia.

Comparison of natural head position in different anteroposterior malocclusions.

PubMed

Hedayati, Zohreh; Paknahad, Maryam; Zorriasatine, Farbod

2013-05-01

The facial esthetics after orthodontic treatment and orthognathic surgery may be affected by the patient's natural head position. The purpose of this study was to evaluate the natural head position for the three skeletal classes of malocclusion. Our sample consisted of 102 lateral cephalometric radiographs of patients aged 15 to 18 years; class I (n=32), class II (n=40) and class III (n=30). Nine landmarks of the craniofacial skeleton and three landmarks of the cervical vertebrae were determined. Variables consisted of two angles for cervical posture (OPT/Hor and CVT/Hor), three angles for craniofacial posture (SN/Ver, PNS-ANS/Ver, and ML/Ver ) and five for craniofacial angulation (SN/OPT, SN/CVT, PNS-ANS/OPT, PNS-ANS/CVT, ML/CVT). The data were analyzed statistically using ANOVA and post hoc tests. PNS-ANS/Ver and SN/Ver differed significantly (p<0.05) among the three groups. There were no significant differences between class I and class II malocclusions for the indicator angles of cranial posture except for ML/Ver. The SN/CVT was significantly different for class I compared to class III patients. A head posture camouflaging the underlying skeletal class III was observed in our population. A more forward head posture was observed in skeletal class III participants compared to skeletal class I and II and that class III patients tended to incline their head more ventral compared to class I participants. These findings may have implications for the amount of jaw movements during surgery particularly in patients with a class III malocclusion.

The impact of computer display height and desk design on 3D posture during information technology work by young adults.

PubMed

Straker, L; Burgess-Limerick, R; Pollock, C; Murray, K; Netto, K; Coleman, J; Skoss, R

2008-04-01

Computer display height and desk design to allow forearm support are two critical design features of workstations for information technology tasks. However there is currently no 3D description of head and neck posture with different computer display heights and no direct comparison to paper based information technology tasks. There is also inconsistent evidence on the effect of forearm support on posture and no evidence on whether these features interact. This study compared the 3D head, neck and upper limb postures of 18 male and 18 female young adults whilst working with different display and desk design conditions. There was no substantial interaction between display height and desk design. Lower display heights increased head and neck flexion with more spinal asymmetry when working with paper. The curved desk, designed to provide forearm support, increased scapula elevation/protraction and shoulder flexion/abduction.

Eye, head, and body coordination during large gaze shifts in rhesus monkeys: movement kinematics and the influence of posture.

PubMed

McCluskey, Meaghan K; Cullen, Kathleen E

2007-04-01

Coordinated movements of the eye, head, and body are used to redirect the axis of gaze between objects of interest. However, previous studies of eye-head gaze shifts in head-unrestrained primates generally assumed the contribution of body movement to be negligible. Here we characterized eye-head-body coordination during horizontal gaze shifts made by trained rhesus monkeys to visual targets while they sat upright in a standard primate chair and assumed a more natural sitting posture in a custom-designed chair. In both postures, gaze shifts were characterized by the sequential onset of eye, head, and body movements, which could be described by predictable relationships. Body motion made a small but significant contribution to gaze shifts that were > or =40 degrees in amplitude. Furthermore, as gaze shift amplitude increased (40-120 degrees ), body contribution and velocity increased systematically. In contrast, peak eye and head velocities plateaued at velocities of approximately 250-300 degrees /s, and the rotation of the eye-in-orbit and head-on-body remained well within the physical limits of ocular and neck motility during large gaze shifts, saturating at approximately 35 and 60 degrees , respectively. Gaze shifts initiated with the eye more contralateral in the orbit were accompanied by smaller body as well as head movement amplitudes and velocities were greater when monkeys were seated in the more natural body posture. Taken together, our findings show that body movement makes a predictable contribution to gaze shifts that is systematically influenced by factors such as orbital position and posture. We conclude that body movements are part of a coordinated series of motor events that are used to voluntarily reorient gaze and that these movements can be significant even in a typical laboratory setting. Our results emphasize the need for caution in the interpretation of data from neurophysiological studies of the control of saccadic eye movements and/or eye-head gaze shifts because single neurons can code motor commands to move the body as well as the head and eyes.

Cranial malformations in related white lions (Panthera leo krugeri).

PubMed

Scaglione, F E; Schröder, C; Degiorgi, G; Zeira, O; Bollo, E

2010-11-01

White lions (Panthera leo krugeri) have never been common in the wild, and at present, the greatest population is kept in zoos where they are bred for biological and biodiversity conservation. During the years 2003 to 2008 in a zoological garden in northern Italy, 19 white lions were born to the same parents, who were in turn paternally consanguineous. Out of the 19 lions, 4 (21%) were stillborn, 13 (69%) died within 1 month, and 1 (5%) was euthanatized after 6 months because of difficulty with prehension of food. Six lions (32%) showed malformations involving the head (jaw, tongue, throat, teeth, and cranial bones). One lion (5%) still alive at 30 months revealed an Arnold-Chiari malformation upon submission for neurological evaluation of postural and gait abnormalities. Paternal consanguinity of the parents, along with inbreeding among white lions in general, could account for the high incidence of congenital malformations of the head in this pride of white lions.

Evaluating a novel analgesic strategy for ring castration of ram lambs.

PubMed

Paull, David R; Small, Alison H; Lee, Caroline; Palladin, Pierre; Colditz, Ian G

2012-09-01

To evaluate the analgesic efficacy of the NSAIDs flunixin and meloxicam administered locally to the scrotum before ring castration. Randomised, controlled, prospective study. Forty eight single born male Merino lambs. Lambs, aged approximately 4 weeks, were allocated to four groups for castration. Groups were: sham control; castration + saline; castration + flunixin; castration + meloxicam. Drugs (5 mL) were administered subcutaneously around the circumference of the scrotum immediately before castration. Cortisol, rectal temperature, haematology and plasma haptoglobin were measured before and up to 48 hours after treatment. Behaviour recorded by video for 12 hours after treatment was classified as pain avoidance behaviours in the first hour and postural behaviours in three 4 hour intervals. Ring castration (saline group) induced a bi-phasic increase in cortisol with peaks at 90 minutes and 24 hours but no significant changes in haematology, haptoglobin or rectal temperature. Pain avoidance behaviours were increased and teat seeking decreased. Normal lying and normal standing postures were decreased and abnormal ventral lying, statue standing, abnormal standing and total abnormal postures increased. Flunixin decreased cortisol at 90 minutes (60.3 versus 117.3 nmol L(-1) ) and cortisol AUC (0-6 hours), decreased elevated leg movement (2.5 versus 5.4 events) and sum of pain avoidance behaviours (8.5 versus 16.7 events), improved time spent in normal ventral lying and decreased abnormal ventral lying and total abnormal postures compared to saline treated lambs. In a similar contrast, meloxicam caused non-significant decreases in cortisol at 90 minutes, cortisol AUC (0-6 hours) and pain avoidance behaviours, and significantly improved the postural behaviours normal ventral lying (26.7 versus 15.4%) and normal standing (13.9 versus 7.5%), and reduced abnormal standing and total abnormal postures. Physiological and behavioural responses associated with ring castration for both NSAID treatment groups were generally greater than sham controls. Locally administered NSAIDs provided partial analgesia for ring castration. © 2012 The Authors. Veterinary Anaesthesia and Analgesia. © 2012 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesiologists.

Development of Abnormality Detection System for Bathers using Ultrasonic Sensors

NASA Astrophysics Data System (ADS)

Ohnishi, Yosuke; Abe, Takehiko; Nambo, Hidetaka; Kimura, Haruhiko; Ogoshi, Yasuhiro

This paper proposes an abnormality detection system for bather sitting in bathtub. Increasing number of in-bathtub drowning accidents in Japan draws attention. Behind this large number of bathing accidents, Japan's unique social and cultural background come surface. For majority of people in Japan, bathing serves purpose in deep warming up of body, relax and enjoyable time. Therefore it is the custom for the Japanese to soak in bathtub. However overexposure to hot water may cause dizziness or fainting, which is possible to cause in-bathtub drowning. For drowning prevention, the system detects bather's abnormal state using an ultrasonic sensor array. The array, which has many ultrasonic sensors, is installed on the ceiling of bathroom above bathtub. The abnormality detection system uses the following two methods: posture detection and behavior detection. The function of posture detection is to estimate the risk of drowning by monitoring bather's posture. Meanwhile, the function of behavior detection is to estimate the risk of drowning by monitoring bather's behavior. By using these methods, the system detects bathers' different state from normal. As a result of experiment with a subject in the bathtub, the system was possible to detect abnormal state using subject's posture and behavior. Therefore the system is useful for monitoring bather to prevent drowning in bathtub.

Improvement in automatic postural coordination following alexander technique lessons in a person with low back pain.

PubMed

Cacciatore, Timothy W; Horak, Fay B; Henry, Sharon M

2005-06-01

The relationship between abnormal postural coordination and back pain is unclear. The Alexander Technique (AT) aims to improve postural coordination by using conscious processes to alter automatic postural coordination and ongoing muscular activity, and it has been reported to reduce low back pain. This case report describes the use of the AT with a client with low back pain and the observed changes in automatic postural responses and back pain. The client was a 49-year-old woman with a 25-year history of left-sided, idiopathic, lumbrosacral back pain. Automatic postural coordination was measured using a force plate during horizontal platform translations and one-legged standing. The client was tested monthly for 4 months before AT lessons and for 3 months after lessons. Before lessons, she consistently had laterally asymmetric automatic postural responses to translations. After AT lessons, the magnitude and asymmetry of her responses and balance improved and her low back pain decreased. Further research is warranted to study whether AT lessons improve low back pain-associated abnormalities in automatic postural coordination and whether improving automatic postural coordination helps to reduce low back pain.

Postural control and perceptive configuration: influence of expertise in gymnastics.

PubMed

Gautier, Geoffroy; Thouvarecq, Régis; Vuillerme, Nicolas

2008-07-01

The purpose of the present experiment was to investigate how postural adaptations to the perceptive configuration are modified by specific gymnastics experience. Two groups, one expert in gymnastics and the other non-expert, had to maintain the erected posture while optical flow was imposed as follows: 20s motionless, 30s approaching motion, and 20s motionless. The centre of pressure and head displacements were analysed. The postural adaptations were characterised by the variability of movements for the flow conditions and by the postural latencies for the flow transitions. The results showed that the gymnasts tended to minimise their body movements and were more stationary (head) but not more stable (COP) than the non-gymnasts. These results suggest that gymnastics experience develops a specific postural adaptability relative to the perceptive configuration. We conclude that a specific postural experience could be considered as an intrinsic constraint, which leads to modification in the patterns of functional adaptation in the perceptive motor space.

Emergence of postural patterns as a function of vision and translation frequency

NASA Technical Reports Server (NTRS)

Buchanan, J. J.; Horak, F. B.; Peterson, B. W. (Principal Investigator)

1999-01-01

Emergence of postural patterns as a function of vision and translation frequency. We examined the frequency characteristics of human postural coordination and the role of visual information in this coordination. Eight healthy adults maintained balance in stance during sinusoidal support surface translations (12 cm peak to peak) in the anterior-posterior direction at six different frequencies. Changes in kinematic and dynamic measures revealed that both sensory and biomechanical constraints limit postural coordination patterns as a function of translation frequency. At slow frequencies (0.1 and 0.25 Hz), subjects ride the platform (with the eyes open or closed). For fast frequencies (1.0 and 1.25 Hz) with the eyes open, subjects fix their head and upper trunk in space. With the eyes closed, large-amplitude, slow-sway motion of the head and trunk occurred for fast frequencies above 0.5 Hz. Visual information stabilized posture by reducing the variability of the head's position in space and the position of the center of mass (CoM) within the support surface defined by the feet for all but the slowest translation frequencies. When subjects rode the platform, there was little oscillatory joint motion, with muscle activity limited mostly to the ankles. To support the head fixed in space and slow-sway postural patterns, subjects produced stable interjoint hip and ankle joint coordination patterns. This increase in joint motion of the lower body dissipated the energy input by fast translation frequencies and facilitated the control of upper body motion. CoM amplitude decreased with increasing translation frequency, whereas the center of pressure amplitude increased with increasing translation frequency. Our results suggest that visual information was important to maintaining a fixed position of the head and trunk in space, whereas proprioceptive information was sufficient to produce stable coordinative patterns between the support surface and legs. The CNS organizes postural patterns in this balance task as a function of available sensory information, biomechanical constraints, and translation frequency.

Trunk Accelerometry Reveals Postural Instability in Untreated Parkinson's Disease

PubMed Central

Mancini, Martina; Horak, Fay B.; Zampieri, Cris; Carlson-Kuhta, Patricia; Nutt, John G.; Chiari, Lorenzo

2017-01-01

While several studies have shown that subjects with advanced Parkinson's disease (PD) exhibit abnormalities in sway parameters during quiet standing, abnormalities of postural sway associated with untreated PD have not been reported. Although not clinically apparent, we hypothesized that spontaneous sway in quiet stance is abnormal in people with untreated PD. We examined 13 subjects, recently diagnosed with PD, who were not yet taking any anti-parkinsonian medications and 12 healthy, age-matched control subjects. Postural sway was measured with a linear accelerometer on the posterior trunk (L5 level) and compared with traditional forceplate measures of sway. Subjects stood for two minutes under two conditions: eyes open (EO) and eyes closed (EC). One of the most discriminative measures of postural changes in subjects with untreated PD was the increased ‘JERK’ of lower trunk in the EO condition, measured with the accelerometer. Root mean square and the frequency dispersion of postural sway in the EO condition also discriminated sway in untreated PD subjects compared to controls subjects. We conclude that accelerometer-based sway metrics could be used as objective measures of postural instability in untreated PD. Accelerometer-based analysis of spontaneous sway may provide a powerful tool for early clinical trials and for monitoring the effects of treatment of balance disorders in subjects with PD. PMID:21641263

Functional morphology of the primate head and neck.

PubMed

Nalley, Thierra K; Grider-Potter, Neysa

2015-04-01

The vertebral column plays a key role in maintaining posture, locomotion, and transmitting loads between body components. Cervical vertebrae act as a bridge between the torso and head and play a crucial role in the maintenance of head position and the visual field. Despite its importance in positional behaviors, the functional morphology of the cervical region remains poorly understood, particularly in comparison to the thoracic and lumbar sections of the spinal column. This study tests whether morphological variation in the primate cervical vertebrae correlates with differences in postural behavior. Phylogenetic generalized least-squares analyses were performed on a taxonomically broad sample of 26 extant primate taxa to test the link between vertebral morphology and posture. Kinematic data on primate head and neck postures were used instead of behavioral categories in an effort to provide a more direct analysis of our functional hypothesis. Results provide evidence for a function-form link between cervical vertebral shape and postural behaviors. Specifically, taxa with more pronograde heads and necks and less kyphotic orbits exhibit cervical vertebrae with longer spinous processes, indicating increased mechanical advantage for deep nuchal musculature, and craniocaudally longer vertebral bodies and more coronally oriented zygapophyseal articular facets, suggesting an emphasis on curve formation and maintenance within the cervical lordosis, coupled with a greater resistance to translation and ventral displacement. These results not only document support for functional relationships in cervical vertebrae features across a wide range of primate taxa, but highlight the utility of quantitative behavioral data in functional investigations. © 2015 Wiley Periodicals, Inc.

The spinal posture of computing adolescents in a real-life setting

PubMed Central

2014-01-01

Background It is assumed that good postural alignment is associated with the less likelihood of musculoskeletal pain symptoms. Encouraging good sitting postures have not reported consequent musculoskeletal pain reduction in school-based populations, possibly due to a lack of clear understanding of good posture. Therefore this paper describes the variability of postural angles in a cohort of asymptomatic high-school students whilst working on desk-top computers in a school computer classroom and to report on the relationship between the postural angles and age, gender, height, weight and computer use. Methods The baseline data from a 12 month longitudinal study is reported. The study was conducted in South African school computer classrooms. 194 Grade 10 high-school students, from randomly selected high-schools, aged 15–17 years, enrolled in Computer Application Technology for the first time, asymptomatic during the preceding month, and from whom written informed consent were obtained, participated in the study. The 3D Posture Analysis Tool captured five postural angles (head flexion, neck flexion, cranio-cervical angle, trunk flexion and head lateral bend) while the students were working on desk-top computers. Height, weight and computer use were also measured. Individual and combinations of postural angles were analysed. Results 944 Students were screened for eligibility of which the data of 194 students are reported. Trunk flexion was the most variable angle. Increased neck flexion and the combination of increased head flexion, neck flexion and trunk flexion were significantly associated with increased weight and BMI (p = 0.0001). Conclusions High-school students sit with greater ranges of trunk flexion (leaning forward or reclining) when using the classroom computer. Increased weight is significantly associated with increased sagittal plane postural angles. PMID:24950887

Surgical planning and innervation in pontine gaze palsy with ipsilateral esotropia.

PubMed

Somer, Deniz; Cinar, Fatma Gul; Kaderli, Ahmet; Ornek, Firdevs

2016-10-01

To discuss surgical intervention strategies among patients with horizontal gaze palsy with concurrent esotropia. Five consecutive patients with dorsal pontine lesions are presented. Each patient had horizontal gaze palsy with symptomatic diplopia as a consequence of esotropia in primary gaze and an anomalous head turn to attain single binocular vision. Clinical findings in the first 2 patients led us to presume there was complete loss of rectus muscle function from rectus muscle palsy. Based on this assumption, medial rectus recessions with simultaneous partial vertical muscle transposition (VRT) on the ipsilateral eye of the gaze palsy and recession-resection surgery on the contralateral eye were performed, resulting in significant motility limitation. Sequential recession-resection surgery without simultaneous VRT on the 3rd patient created an unexpected motility improvement to the side of gaze palsy, an observation differentiating rectus muscle palsy from paresis. Recession combined with VRT approach in the esotropic eye was abandoned on subsequent patients. Simultaneous recession-resection surgery without VRT in the next 2 patients resulted in alleviation of head postures, resolution of esotropia, and also substantial motility improvements to the ipsilateral hemifield of gaze palsy without limitations in adduction and vertical deviations. Ocular misalignment and abnormal head posture as a result of conjugate gaze palsy can be successfully treated by basic recession-resection surgery, with the advantage of increasing versions to the ipsilateral side of the gaze palsy. Improved motility after surgery presumably represents paresis, not "paralysis," with residual innervation in rectus muscles. Copyright © 2016 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

The influence of unilateral saccular impairment on functional balance performance and self-report dizziness.

PubMed

McCaslin, Devin L; Jacobson, Gary P; Grantham, Sarah L; Piker, Erin G; Verghese, Susha

2011-09-01

Postural stability in humans is largely maintained by vestibular, visual, and somatosensory inputs to the central nervous system. Recent clinical advances in the assessment of otolith function (e.g., cervical and ocular vestibular evoked myogenic potentials [cVEMPs and oVEMPs], subjective visual vertical [SVV] during eccentric rotation) have enabled investigators to identify patients with unilateral otolith impairments. This research has suggested that patients with unilateral otolith impairments perform worse than normal healthy controls on measures of postural stability. It is not yet known if patients with unilateral impairments of the saccule and/or inferior vestibular nerve (i.e., unilaterally abnormal cVEMP) perform differently on measures of postural stability than patients with unilateral impairments of the horizontal SCC (semicircular canal) and/or superior vestibular nerve (i.e., unilateral caloric weakness). Further, it is not known what relationship exists, if any, between otolith system impairment and self-report dizziness handicap. The purpose of this investigation was to determine the extent to which saccular impairments (defined by a unilaterally absent cVEMP) and impairments of the horizontal semicircular canal (as measured by the results of caloric testing) affect vestibulospinal function as measured through the Sensory Organization Test (SOT) of the computerized dynamic posturography (CDP). A secondary objective of this investigation was to measure the effects, if any, that saccular impairment has on a modality-specific measure of health-related quality of life. A retrospective cohort study. Subjects were assigned to one of four groups based on results from balance function testing: Group 1 (abnormal cVEMP response only), Group 2 (abnormal caloric response only), Group 3 (abnormal cVEMP and abnormal caloric response), and Group 4 (normal control group). Subjects were 92 adult patients: 62 were seen for balance function testing due to complaints of dizziness, vertigo, or unsteadiness, and 30 served as controls. All subjects underwent videonystagmography or electronystagmography (VNG/ENG), vestibular evoked myogenic potentials (VEMPs), self-report measures of self-perceived dizziness disability/handicap (Dizziness Handicap Inventory), and tests of postural control (Neurocom Equitest). Subjects were categorized into one of four groups based on balance function test results. All variables were subjected to a multifactor analysis of variance (ANOVA). The Dizziness Handicap Inventory (DHI) total scores and equilibrium scores served as the dependent variables. Results showed that patients with abnormal unilateral saccular or inferior vestibular nerve function (i.e., abnormal cVEMP) demonstrated significantly impaired postural control when compared to normal participants. However, this group demonstrated significantly better postural stability when compared to the group with abnormal caloric responses alone and the group with abnormal caloric responses and abnormal cVEMP results. Patients with an abnormal cVEMP did not differ significantly on the DHI compared to the other two impaired groups. We interpret these findings as evidence that a significantly asymmetrical cVEMP in isolation negatively impacts performance on measures of postural control compared to normal subjects but not compared to patients with significant caloric weaknesses. However, patients with a unilaterally abnormal cVEMP do not differ from patients with significant caloric weaknesses in regard to self-perceived dizziness handicap. American Academy of Audiology.

Postural responses of head and foot cutaneous microvascular flow and their sensitivity to bed rest

NASA Technical Reports Server (NTRS)

Aratow, Michael; Hargens, Alan R.; Meyer, J.-UWE; Arnaud, Sara B.

1991-01-01

To explore the mechanism for facial puffiness, headache, and nasal congestion associated with microgravity and cephalad fluid shifts, the postural responses of the cutaneous microcirculation (CMC) in the forehead and dorsum of the foot of eight healthy men were studied by changing body position on a tilt table and measuring blood flows with a laser Doppler flowmeter. Increasing arterial pressure in the feet by moving from a -6-deg head-down tilt to a 60-deg head-up posture decreased foot CMC by 46.5 + or - 12.0 percent. Raising arterial pressure in the head increased forehead CMC by 25.5 + or - 0.7 percent (p less than 0.05). To investigate the possibility that these opposite responses could be modified by simulated microgravity, tilt test were repeated after 7 d of -6-deg head-down-tilt bed rest. The responses were not significantly different from those recorded before bed rest. Therefore, CMC in the feet is well regulated to prevent edema when shifting to an upright position, whereas there is less regulation in the head CMC.

Children's Understanding of Nonverbal Expressions of Pride

ERIC Educational Resources Information Center

Nelson, Nicole L.; Russell, James A.

2012-01-01

To chart the developmental path of children's attribution of pride to others, we presented children (4 years 0 month to 11 years 11 months of age, N = 108) with video clips of head-and-face, body posture, and multi-cue (both head-and-face and body posture simultaneously) expressions that adults consider to convey pride. Across age groups, 4- and…

Role of orientation reference selection in motion sickness, supplement 2S

NASA Technical Reports Server (NTRS)

Peterka, Robert J.; Black, F. Owen

1987-01-01

Previous experiments with moving platform posturography have shown that different people have varying abilities to resolve conflicts among vestibular, visual, and proprioceptive sensory signals. The conceptual basis of the present proposal hinges on the similarities between the space motion sickness problem and the sensory orientation reference selection problems associated with benign paroxysmal positional vertigo (BPPV) syndrome. These similarities include both etiology related to abnormal vertical canal-otolith function, and motion sickness initiating events provoked by pitch and roll head movements. The objectives are to explore and quantify the orientation reference selection abilities of subjects and the relation of this selection to motion sickness in humans. The overall objectives are to determine: if motion sickness susceptibility is related to sensory orientation reference selection abilities of subjects; if abnormal vertical canal-otolith function is the source of abnormal posture control strategies and if it can be quantified by vestibular and oculomotor reflex measurements, and if it can be quantified by vestibular and oculomotor reflex measurements; and quantifiable measures of perception of vestibular and visual motion cues can be related to motion sickness susceptibility and to orientation reference selection ability.

Cervical Joint Position Sense in Hypobaric Conditions: A Randomized Double-Blind Controlled Trial.

PubMed

Bagaianu, Diana; Van Tiggelen, Damien; Duvigneaud, N; Stevens, Veerle; Schroyen, Danny; Vissenaeken, Dirk; D'Hondt, Gino; Pitance, Laurent

2017-09-01

Well-adapted motor actions require intact and well-integrated information from all of the sensory systems, specifically the visual, vestibular, and somatosensory systems, including proprioception. Proprioception is involved in the sensorimotor control by providing the central nervous system with an updated body schema of the biomechanical and spatial properties of the body parts. With regard to the cervical spine, proprioceptive information from joint and muscle mechanoreceptors is integrated with vestibular and visual feedback to control head position, head orientation, and whole body posture. Postural control is highly complex and proprioception from joints is an important contributor to the system. Altitude has been used as a paradigm to study the mechanisms of postural control. Determining the mechanisms of postural control that are affected by moderate altitude is important as unpressurized aircrafts routinely operate at altitudes where hypoxia may be a concern. Deficits in motor performance arise when the reliance on proprioceptive feedback is abolished either experimentally or because of a disorder. As pilots require good neck motor control to counteract the weight of their head gear and proprioceptive information plays an important role in this process, the aim of this study was to determine if hypoxia at moderate altitudes would impair proprioception measured by joint position sense of the cervical spine in healthy subjects. Thirty-six healthy subjects (Neck Disability Index < 5) volunteered to participate. Neck position sense was evaluated using a three-dimensional motion analyzer. To create the environment, a hypobaric chamber was used to simulate artificial moderate altitude. Head repositioning error was measured by asking the subject to perform a head-to-neutral task after submaximal flexion-extension and right/left rotation movements, and a head-to-target task, in which the subjects had to return to a 30° right and left rotation position. Exposure to artificial acute moderate altitude of 7,000 feet had no significant effects on cervical joint position sense measured by head repositioning accuracy in healthy subjects. Discussion/impact/recommendations: Postural control mechanisms are very sensitive to acute mild hypoxia and have been recently investigated. Acute hypobaric hypoxia at moderate and high altitudes has a negative effect on postural control. However, which part of the postural system is affected has not yet been determined and proprioception has been little investigated. The results from this study highlighted that in healthy subjects with good cervical spine proprioception at baseline, artificial hypoxia induced by the simulation of moderate altitude does not increase head repositioning error. Further studies should investigate cervical joint position sense in real aircraft, at different altitudes and in a group of experienced helicopter pilots, to evaluate the impact of moderate altitude on cervical joint position sense in a different population. Conducting the same experiments in a population of pilots and in real flight conditions should be considered, since various factors such as the level of proprioception, head posture, type of movement, head load, muscle fatigue, flight altitude, and the length of flight time might influence the kinesthetic sensitivity. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

Ergonomic strategies to improve radiographers' posture during mammography activities.

PubMed

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.

Developing Gene Silencing for the Study and Treatment of Dystonia

DTIC Science & Technology

2015-11-01

cause abnormal twisting postures. DYT1 dystonia is an autosomal dominant disease with onset of dystonia during childhood . The most common early onset...SUPPLEMENTARY NOTES 14. ABSTRACT Dystonia is a debilitating neurological disease with no cure. In dystonia, there are involuntary muscle contractions that...is a debilitating neurological disease with no cure that is characterized by involuntary muscle contractions that cause abnormal twisting postures

Children's catching performance when the demands on the postural system is altered.

PubMed

Angelakopoulos, Georgios T; Tsorbatzoudis, Haralambos; Grouios, George

2014-07-01

In many dynamic interceptive actions performers need to integrate activity of manual and postural subsystems for successful performance. Groups of different skill level (poor and good catchers), (mean age = 9.1 and 9.4 respectively) were required to perform one-handed catches under different postural constraints: standing; standing in contact with a postural support aid by their side (PSAS) or to the left of their trunk (PSAF); Tandem; and sitting (control). Results revealed that, for poor catchers, the number of successful catches increased and grasp errors decreased significantly when sitting and with both postural aids in comparison with standing alone and Tandem conditions. Kinematic analyses showed that the postural aid devices reduced head sway in the anterior-posterior direction, while the PSAF reduced lateral head sway. The poor catchers' performance benefited from an enlarged support surface, and reduction of lateral sway. Good catchers performed successfully under all task constraints, signifying the existence of a functional relationship between postural and grasping subsystems during performance. The results are discussed in the frame of Bernstein's (1967) and Newell's (1986) theory.

The Relationship Between the Stomatognathic System and Body Posture

PubMed Central

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

Reliability and validity of the range of motion scale (ROMS) in patients with abnormal postures.

PubMed

van Rooijen, Diana E; Lalli, Stefania; Marinus, Johan; Maihöfner, Christian; McCabe, Candida S; Munts, Alex G; van der Plas, Anton A; Tijssen, Marina A J; van de Warrenburg, Bart P; Albanese, Alberto; van Hilten, Jacobus J

2015-03-01

Sustained abnormal postures (i.e., fixed dystonia) are the most frequently reported motor abnormalities in complex regional pain syndrome (CRPS), but these symptoms may also develop after peripheral trauma without CRPS. Currently, there is no valid and reliable measurement instrument available to measure the severity and distribution of these postures. The range of motion scale (ROMS) was therefore developed to assess the severity based on the possible active range of motion of all joints (arms, legs, trunk, and neck), and the present study evaluates its reliability and validity. Inter- and intra-rater reliability of the ROMS was determined in 16 patients with abnormal sustained postures, who were videotaped following a standard video protocol in a university hospital. The recordings were rated by a panel of international experts. In addition, 30 patients were clinically tested with both the Burke-Fahn-Marsden (BFM) scale as well as the ROMS to assess construct validity. Inter-rater reliability for total ROMS scores showed an intra-class correlation coefficient (ICC) of 0.85. The majority of the scores for the separate joints (13 out of 18) demonstrated an almost perfect agreement with ICCs ranging from 0.81 to 0.94; of the other items, one showed fair, one moderate, and three substantial agreement. The ICCs for the intra-rater reliability ranged from moderate to almost perfect (0.68-0.98). Spearman's correlation coefficients between corresponding body areas as measured with the ROMS or BFM were all above 0.82. The ROMS is a reliable and valid instrument to evaluate the severity and distribution of sustained abnormal postures. Wiley Periodicals, Inc.

Pilot Study: Measuring the Effects of Center of Gravity Shift on Postural Stability

NASA Technical Reports Server (NTRS)

Times-Marshall, Chelsea; Reschke, Millard

2009-01-01

It has been shown that astronauts returning from space often experience postural instability due to the stimulus rearrangement of the visual, vestibular, and proprioceptive systems. However, postural control may also be influenced by the head-ward shift in their center of gravity (CG) that occurs as a result of the expansion of their spinal column by as much as two inches during long duration space flight, as well as the CG shift that occurs from the Life Support Pack on the extra-vehicular activity (EVA) suit. This study investigated the effect on postural stability after (1) an immediate shift in the CG towards the head, (2) a 30 minute adaptation to the shifted CG, and (3) immediate shift of the CG back to normal, accomplished by donning and removing a modified backpack. We hypothesized that at each immediate shift in CG, postural performance will be compromised.

Clinical and ocular motor analysis of the infantile nystagmus syndrome in the first 6 months of life.

PubMed

Hertle, R W; Maldanado, V K; Maybodi, M; Yang, D

2002-06-01

The infantile nystagmus syndrome (INS) usually begins in infancy and may or may not be associated with visual sensory system abnormalities. Little is known about its specific waveforms in the first 6 months of life or their relation to the developing visual system. This study identifies the clinical and ocular motility characteristics of the INS and establishes the range of waveforms present in the first 6 months of life. 27 infants with involuntary ocular oscillations typical of INS are included in this analysis. They were evaluated both clinically and with motility recordings. Eye movement analysis was performed off line from computer analysis of digitised data. Variables analysed included age, sex, vision, ocular abnormalities, head position, and null zone, neutral zone characteristics, symmetry, conjugacy, waveforms, frequencies, and foveation times. Ages ranged from 3 to 6.5 months (average 4.9 months). 15 patients (56%) had abnormal vision for age, nine (33%) had strabismus, five (19%) had an anomalous head posture, 13 (48%) had oculographic null and neutral positions, nine (33%) had binocular asymmetry, and only two showed consistent dysconjugacy. Average binocular frequency was 3.3 Hz, monocular frequency 6.6 Hz. Average foveation periods were longer and more "jerk" wave forms were observed in those patients with normal vision. Common clinical characteristics and eye movement waveforms of INS begin in the first few months of infancy and waveform analysis at this time may help with both diagnosis and visual status.

Social Postural Coordination

ERIC Educational Resources Information Center

Varlet, Manuel; Marin, Ludovic; Lagarde, Julien; Bardy, Benoit G.

2011-01-01

The goal of the current study was to investigate whether a visual coupling between two people can produce spontaneous interpersonal postural coordination and change their intrapersonal postural coordination involved in the control of stance. We examined the front-to-back head displacements of participants and the angular motion of their hip and…

Survey of faulty postures and associated factors among Chinese adolescents.

PubMed

Cho, Chiung-Yu

2008-03-01

This study investigates the prevalence of common faulty postures among adolescents and identify if significant relationships existed among the number of faulty postures, psychologic distress, and musculoskeletal symptoms. The Musculoskeletal Questionnaire and Chinese Health Questionnaire were randomly distributed to 300 high school students in the Tainan area. On-campus postural screening, which included digital photography, manual muscle tests, and flexibility tests, was also performed. Two hundred eighty-seven participants completed all of the evaluations. The most common faulty posture was uneven shoulder level (36%), followed by forward head posture (25%). There was a sex difference between groups. The incidence of forward head posture for the male students was higher than that of the female students (P < .0001). In addition, the high psychologic distress group tended to have a higher prevalence of uneven shoulder height than that of the low psychologic distress group (P < .0001). As for the correlation analysis, the researchers did not find a high correlation among the scores of the faulty posture, psychologic distress, and musculoskeletal symptoms. The results of this study show that the incidence of faulty posture was high for the adolescent group, especially for the uneven shoulder level. Subjects' awareness about being assessed might decrease the incidence for some faulty posture. However, the relationships among the number of faulty postures, psychologic distress, and musculoskeletal symptoms were low. We suggest that there are multiple factors that might contribute to musculoskeletal symptoms; faulty posture could be one important factor that causes symptoms.

Low back pain prevalence in healthcare professionals and identification of factors affecting low back pain.

PubMed

Çınar-Medeni, Özge; Elbasan, Bulent; Duzgun, Irem

2017-01-01

Work-related musculoskeletal system diseases are commonly observed among nurses, physiotherapists, dentists, and dieticians. To assess working postures of nurses, physiotherapists, dentists and dieticians, to identify whether low back pain (LBP) is present, and to put forth the correlation between LBP, working posture, and other factors. Twenty seven physiotherapists, 34 nurses, 30 dentists, and 16 dieticians were included. Impairment ratings of cases with LBP were analysed with Quebec Back Pain Disability Scale (Quebec). Working postures were analysed with Owako Working Posture Analysis System. LBP was observed in 70.09% of healthcare professionals. Of the individuals suffering from LBP, 57.2% were working with a risky posture. 40.63% of individuals without LBP were using risky working postures. Trunk and head posture distribution of individuals with and without LBP was found as different from each other (p < 0.05). LBP prevalence of dentists and nurses were higher compared to other groups (p < 0.05). Quebec scores of professionals with LBP were not different among occupations (p > 0.05). Quebec scores were observed as correlated with various factors in various occupation groups. Considering that head-neck and trunk postures are changeable factors that are among the factors affecting LBP, correcting the working posture gains importance.

Postural Consequences of Cervical Sagittal Imbalance: A Novel Laboratory Model.

PubMed

Patwardhan, Avinash G; Havey, Robert M; Khayatzadeh, Saeed; Muriuki, Muturi G; Voronov, Leonard I; Carandang, Gerard; Nguyen, Ngoc-Lam; Ghanayem, Alexander J; Schuit, Dale; Patel, Alpesh A; Smith, Zachary A; Sears, William

2015-06-01

A biomechanical study using human spine specimens. To study postural compensations in lordosis angles that are necessary to maintain horizontal gaze in the presence of forward head posture and increasing T1 sagittal tilt. Forward head posture relative to the shoulders, assessed radiographically using the horizontal offset distance between the C2 and C7 vertebral bodies (C2-C7 [sagittal vertical alignment] SVA), is a measure of global cervical imbalance. This may result from kyphotic alignment of cervical segments, muscle imbalance, as well as malalignment of thoracolumbar spine. Ten cadaveric cervical spines (occiput-T1) were tested. The T1 vertebra was anchored to a tilting and translating base. The occiput was free to move vertically but its angular orientation was constrained to ensure horizontal gaze regardless of sagittal imbalance. A 5-kg mass was attached to the occiput to mimic head weight. Forward head posture magnitude and T1 tilt were varied and motions of individual vertebrae were measured to calculate C2-C7 SVA and lordosis across C0-C2 and C2-C7. Increasing C2-C7 SVA caused flexion of lower cervical (C2-C7) segments and hyperextension of suboccipital (C0-C1-C2) segments to maintain horizontal gaze. Increasing kyphotic T1 tilt primarily increased lordosis across the C2-C7 segments. Regression models were developed to predict the compensatory C0-C2 and C2-C7 angulation needed to maintain horizontal gaze given values of C2-C7 SVA and T1 tilt. This study established predictive relationships between radiographical measures of forward head posture, T1 tilt, and postural compensations in the cervical lordosis angles needed to maintain horizontal gaze. The laboratory model predicted that normalization of C2-C7 SVA will reduce suboccipital (C0-C2) hyperextension, whereas T1 tilt reduction will reduce the hyperextension in the C2-C7 segments. The predictive relationships may help in planning corrective strategy in patients experiencing neck pain, which may be attributed to sagittal malalignment. N/A.

A research on the postural stability of a person wearing the lower limb exoskeletal robot by the HAT model.

PubMed

Chang, Minsu; Kim, Yeongmin; Lee, Yoseph; Jeon, Doyoung

2017-07-01

This paper proposes a method of detecting the postural stability of a person wearing the lower limb exoskeletal robot with the HAT(Head-Arm-Trunk) model. Previous studies have shown that the human posture is stable when the CoM(Center of Mass) of the human body is placed on the BoS(Base of Support). In the case of the lower limb exoskeletal robot, the motion data, which are used for the CoM estimation, are acquired by sensors in the robot. The upper body, however, does not have sensors in each segment so that it may cause the error of the CoM estimation. In this paper, the HAT(Head-Arm-Trunk) model which combines head, arms, and torso into a single segment is considered because the motion of head and arms are unknown due to the lack of sensors. To verify the feasibility of HAT model, the reflecting markers are attached to each segment of the whole human body and the exact motion data are acquired by the VICON to compare the COM of the full body model and HAT model. The difference between the CoM with full body and that with HAT model is within 20mm for the various motions of head and arms. Based on the HAT model, the XCoM(Extrapolated Center of Mass) which includes the velocity of the CoM is used for prediction of the postural stability. The experiment of making unstable posture shows that the XCoM of the whole body based on the HAT model is feasible to detect the instance of postural instability earlier than the CoM by 20-250 msec. This result may be used for the lower limb exoskeletal robot to prepare for any action to prevent the falling down.

Postural Control Characteristics during Single Leg Standing of Individuals with a History of Ankle Sprain: Measurements Obtained Using a Gravicorder and Head and Foot Accelerometry.

PubMed

Abe, Yota; Sugaya, Tomoaki; Sakamoto, Masaaki

2014-03-01

[Purpose] This study aimed to validate the postural control characteristics of individuals with a history of ankle sprain during single leg standing by using a gravicorder and head and foot accelerometry. [Subjects] Twenty subjects with and 23 subjects without a history of ankle sprain (sprain and control groups, respectively) participated. [Methods] The anteroposterior, mediolateral, and total path lengths, as well as root mean square (RMS) of each length, were calculated using the gravicorder. The anteroposterior, mediolateral, and resultant acceleration of the head and foot were measured using accelerometers and were evaluated as the ratio of the acceleration of the head to the foot. [Results] There was no significant difference between the two groups in path length or RMS acceleration of the head and foot. However, the ratios of the mediolateral and resultant components were significantly higher in the sprain group than in the control group. [Conclusion] Our findings suggest that individuals with a history of ankle sprain have a higher head-to-foot acceleration ratio and different postural control characteristics than those of control subjects.

Relationship between craniomandibular disorders and poor posture.

PubMed

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 < 0.001, p < 0.05, p < 0.01). 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.

Effect of complete dentures on dynamic measurement of changing head position: A pilot study.

PubMed

Usumez, Aslihan; Usumez, Serdar; Orhan, Metin

2003-10-01

Complete dentures contribute significantly to the facial esthetics of edentulous patients. However, information as to the effect of complete dentures on the natural position of the head is limited. The purpose of this pilot study was to evaluate the immediate and 30-day effect of wearing complete dentures on the dynamic natural head position measured during walking. The sample consisted of a volunteer group of 16 patients, 8 women and 8 men, who received new complete dentures. The ages of the subjects ranged from 45 to 64 years (mean=52 years). Dynamic measurement of head posture was carried out by a specially constructed inclinometer device. Each subject in turn was fitted with the inclinometer system and instructed to walk in a relaxed manner for 5 minutes. The data, measured as degrees, were stored in a pocket data logger. This procedure was repeated before insertion of dentures (T1), immediately after insertion of dentures (T2), and 30 days after insertion of dentures (T3). Stored dynamic head posture data were transferred to computer for analysis. The means of the measurements were statistically compared with Friedman and following Wilcoxon tests (alpha =.05). Twelve of 16 (75%) subjects showed an average of 4.6 degrees of cranial extension immediately after insertion of dentures. Six (37.5%) subjects showed an average of 6.4 degrees of cranial flexion, and 8 (50%) subjects showed an average of 5.2 degrees of cranial extension at T3 relative to the T1 measurement. Dynamic head posture measurements of the other 2 subjects remained unchanged. There were significant differences between different measurements of dynamic head posture positions (P<.025). However, only the T1 and T2 measurements were significantly different (P<.015). The findings indicate that the statistically significant average extension 4.6 degrees in subjects immediately after insertion of complete dentures was not stable after a 30-day evaluation period and did not produce any statistically significant change. The overall effect of wearing dentures was an irregular flexion or extension pattern on dynamic head posture.

Association between vestibulo-ocular reflex suppression, balance, gait, and fall risk in ageing and neurodegenerative disease: protocol of a one-year prospective follow-up study.

PubMed

Srulijes, Karin; Mack, David J; Klenk, Jochen; Schwickert, Lars; Ihlen, Espen A F; Schwenk, Michael; Lindemann, Ulrich; Meyer, Miriam; Srijana, K C; Hobert, Markus A; Brockmann, Kathrin; Wurster, Isabel; Pomper, Jörn K; Synofzik, Matthis; Schneider, Erich; Ilg, Uwe; Berg, Daniela; Maetzler, Walter; Becker, Clemens

2015-10-09

Falls frequency increases with age and particularly in neurogeriatric cohorts. The interplay between eye movements and locomotion may contribute substantially to the occurrence of falls, but is hardly investigated. This paper provides an overview of current approaches to simultaneously measure eye and body movements, particularly for analyzing the association of vestibulo-ocular reflex (VOR) suppression, postural deficits and falls in neurogeriatric risk cohorts. Moreover, VOR suppression is measured during head-fixed target presentation and during gaze shifting while postural control is challenged. Using these approaches, we aim at identifying quantitative parameters of eye-head-coordination during postural balance and gait, as indicators of fall risk. Patients with Progressive Supranuclear Palsy (PSP) or Parkinson's disease (PD), age- and sex-matched healthy older adults, and a cohort of young healthy adults will be recruited. Baseline assessment will include a detailed clinical assessment, covering medical history, neurological examination, disease specific clinical rating scales, falls-related self-efficacy, activities of daily living, neuro-psychological screening, assessment of mobility function and a questionnaire for retrospective falls. Moreover, participants will simultaneously perform eye and head movements (fixating a head-fixed target vs. shifting gaze to light emitting diodes in order to quantify vestibulo-ocular reflex suppression ability) under different conditions (sitting, standing, or walking). An eye/head tracker synchronized with a 3-D motion analysis system will be used to quantify parameters related to eye-head-coordination, postural balance, and gait. Established outcome parameters related to VOR suppression ability (e.g., gain, saccadic reaction time, frequency of saccades) and motor related fall risk (e.g., step-time variability, postural sway) will be calculated. Falls will be assessed prospectively over 12 months via protocols and monthly telephone interviews. This study protocol describes an experimental setup allowing the analysis of simultaneously assessed eye, head and body movements. Results will improve our understanding of the influence of the interplay between eye, head and body movements on falls in geriatric high-risk cohorts.

Role of orientation reference selection in motion sickness

NASA Technical Reports Server (NTRS)

Peterka, Robert J.; Black, F. Owen

1988-01-01

Previous experiments with moving platform posturography have shown that different people have varying abilities to resolve conflicts among vestibular, visual, and proprioceptive sensory signals used to control upright posture. In particular, there is one class of subjects with a vestibular disorder known as benign paroxysmal positional vertigo (BPPV) who often are particularly sensitive to inaccurate visual information. That is, they will use visual sensory information for the control of their posture even when that visual information is inaccurate and is in conflict with accurate proprioceptive and vestibular sensory signals. BPPV has been associated with disorders of both posterior semicircular canal function and possibly otolith function. The present proposal hopes to take advantage of the similarities between the space motion sickness problem and the sensory orientation reference selection problems associated with the BPPV syndrome. These similarities include both etiology related to abnormal vertical canal-otolith function, and motion sickness initiating events provoked by pitch and roll head movements. The objectives of this proposal are to explore and quantify the orientation reference selection abilities of subjects and the relation of this selection to motion sickness in humans.

The relationship between sitting posture and seated-related upper quadrant musculoskeletal pain in computing South African adolescents: A prospective study.

PubMed

Brink, Yolandi; Louw, Quinette; Grimmer, Karen; Jordaan, Esmè

2015-12-01

There is evidence that consistent sitting for prolonged periods is associated with upper quadrant musculoskeletal pain (UQMP). It is unclear whether postural alignment is a significant risk factor. The aim of the prospective study (2010-2011) was to ascertain if three-dimensional sitting postural angles, measured in a real-life school computer classroom setting, predict seated-related UQMP. Asymptomatic Grade 10 high-school students, aged 15-17 years, undertaking Computer Application Technology, were eligible to participate. Using the 3D Posture Analysis Tool, sitting posture was measured while students used desk-top computers. Posture was reported as five upper quadrant angles (Head flexion, Neck flexion; Craniocervical angle, Trunk flexion and Head lateral bending). The Computer Usage Questionnaire measured seated-related UQMP and hours of computer use. The Beck Depression Inventory and the Multidimensional Anxiety Scale for Children assessed psychosocial factors. Sitting posture, computer use and psychosocial factors were measured at baseline. UQMP was measured at six months and one-year follow-up. 211, 190 and 153 students participated at baseline, six months and one-year follow-up respectively. 34.2% students complained of seated-related UQMP during the follow-up period. Increased head flexion (HF) predicted seated-related UQMP developing over time for a small group of students with pain scores greater than the 90th pain percentile, adjusted for age, gender, BMI, computer use and psychosocial factors (p = 0.003). The pain score increased 0.22 points per 1° increase in HF. Classroom ergonomics and postural hygiene should therefore focus on reducing large HF angles among computing adolescents. Copyright © 2015 Elsevier Ltd. All rights reserved.

Unexplained head tilt following surgical treatment of congenital esotropia: a postural manifestation of dissociated vertical divergence

PubMed Central

Brodsky, M C; Jenkins, R; Nucci, P

2004-01-01

Background: Strabismus surgery for congenital esotropia can be complicated by the development of a postoperative head tilt. Purpose: To determine the pathophysiology of acquired head tilting following horizontal realignment of the eyes in children with congenital esotropia. Materials and methods: Retrospective analysis of nine children with congenital esotropia who developed unexplained head tilts following horizontal realignment of the eyes. Results: Shortly after strabismus surgery, each child developed a head tilt in association with asymmetrical dissociated vertical divergence (DVD). Five children maintained a head tilt toward the side of the fixing eye (group 1), which did not serve to control the DVD. Four children maintained a head tilt toward the side of the hyperdeviating eye, which served to control the DVD (group 2). Children in group 2 had earlier horizontal muscle surgery and developed better stereopsis than those in group 1, suggesting that the higher degree of single binocular vision and stereopsis in these children may have led to a compensatory torticollis to control an asymmetrical DVD. Conclusions: The onset of an unexpected head tilt after congenital esotropia surgery is usually a postural manifestation of asymmetrical DVD. In this setting, a head tilt toward the side of the fixing eye corresponds with a postural manifestation of the underlying central vestibular imbalance that produces DVD, while a head tilt toward the side of the hyperdeviating eye serves to counteract the hyperdeviation and stabilise binocular vision. PMID:14736789

Context-dependent arm pointing adaptation

NASA Technical Reports Server (NTRS)

Seidler, R. D.; Bloomberg, J. J.; Stelmach, G. E.

2001-01-01

We sought to determine the effectiveness of head posture as a contextual cue to facilitate adaptive transitions in manual control during visuomotor distortions. Subjects performed arm pointing movements by drawing on a digitizing tablet, with targets and movement trajectories displayed in real time on a computer monitor. Adaptation was induced by presenting the trajectories in an altered gain format on the monitor. The subjects were shown visual displays of their movements that corresponded to either 0.5 or 1.5 scaling of the movements made. Subjects were assigned to three groups: the head orientation group tilted the head towards the right shoulder when drawing under a 0.5 gain of display and towards the left shoulder when drawing under a 1.5 gain of display; the target orientation group had the home and target positions rotated counterclockwise when drawing under the 0.5 gain and clockwise for the 1.5 gain; the arm posture group changed the elbow angle of the arm they were not drawing with from full flexion to full extension with 0.5 and 1.5 gain display changes. To determine if contextual cues were associated with display alternations, the gain changes were returned to the standard (1.0) display. Aftereffects were assessed to determine the efficacy of the head orientation contextual cue compared to the two control cues. The head orientation cue was effectively associated with the multiple gains. The target orientation cue also demonstrated some effectiveness while the arm posture cue did not. The results demonstrate that contextual cues can be used to switch between multiple adaptive states. These data provide support for the idea that static head orientation information is a crucial component to the arm adaptation process. These data further define the functional linkage between head posture and arm pointing movements.

Context-Dependent Arm Pointing Adaptation

NASA Technical Reports Server (NTRS)

Seidler, R. D.; Bloomberg, J. J.; Stelmach, G. E.

2000-01-01

We sought to determine the effectiveness of head posture as a contextual cue to facilitate adaptive transitions in manual control during visuomotor distortions. Subjects performed arm pointing movements by drawing on a digitizing tablet, with targets and movement trajectories displayed in real time on a computer monitor. Adaptation was induced by presenting the trajectories in an altered gain format on the monitor. The subjects were shown visual displays of their movements that corresponded to either 0.5 or 1.5 scaling of the movements made. Subjects were assigned to three groups: the head orientation group tilted the head towards the right shoulder when drawing under a 0.5 gain of display and towards the left shoulder when drawing under a 1.5 gain of display, the target orientation group had the home & target positions rotated counterclockwise when drawing under the 0.5 gain and clockwise for the 1.5 gain, the arm posture group changed the elbow angle of the arm they were not drawing with from full flexion to full extension with 0.5 and 1.5 gain display changes. To determine if contextual cues were associated with display alternations, the gain changes were returned to the standard (1.0) display. Aftereffects were assessed to determine the efficacy of the head orientation contextual cue. . compared to the two control cues. The head orientation cue was effectively associated with the multiple gains. The target orientation cue also demonstrated some effectiveness while the.arm posture cue did not. The results demonstrate that contextual cues can be used to switch between multiple adaptive states. These data provide support for the idea that static head orientation information is a crucial component to the arm adaptation process. These data further define the functional linkage between head posture and arm pointing movements.

Postural complexity influences development in infants born preterm with brain injury: relating perception-action theory to 3 cases.

PubMed

Dusing, Stacey C; Izzo, Theresa; Thacker, Leroy R; Galloway, James Cole

2014-10-01

Perception-action theory suggests a cyclical relationship between movement and perceptual information. In this case series, changes in postural complexity were used to quantify an infant's action and perception during the development of early motor behaviors. Three infants born preterm with periventricular white matter injury were included. Longitudinal changes in postural complexity (approximate entropy of the center of pressure), head control, reaching, and global development, measured with the Test of Infant Motor Performance and the Bayley Scales of Infant and Toddler Development, were assessed every 0.5 to 3 months during the first year of life. All 3 infants demonstrated altered postural complexity and developmental delays. However, the timing of the altered postural complexity and the type of delays varied among the infants. For infant 1, reduced postural complexity or limited action while learning to control her head in the midline position may have contributed to her motor delay. However, her ability to adapt her postural complexity eventually may have supported her ability to learn from her environment, as reflected in her relative cognitive strength. For infant 2, limited early postural complexity may have negatively affected his learning through action, resulting in cognitive delay. For infant 3, an increase in postural complexity above typical levels was associated with declining neurological status. Postural complexity is proposed as a measure of perception and action in the postural control system during the development of early behaviors. An optimal, intermediate level of postural complexity supports the use of a variety of postural control strategies and enhances the perception-action cycle. Either excessive or reduced postural complexity may contribute to developmental delays in infants born preterm with white matter injury. © 2014 American Physical Therapy Association.

Stance Postural Strategies in Patients with Chronic Inflammatory Demyelinating Polyradiculoneuropathy

PubMed Central

Missori, Paolo; Trompetto, Carlo; Fattapposta, Francesco

2016-01-01

Introduction Polyneuropathy leads to postural instability and an increased risk of falling. We investigated how impaired motor impairment and proprioceptive input due to neuropathy influences postural strategies. Methods Platformless bisegmental posturography data were recorded in healthy subjects and patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Each subject stood on the floor, wore a head and a hip electromagnetic tracker. Sway amplitude and velocity were recorded and the mean direction difference (MDD) in the velocity vector between trackers was calculated as a flexibility index. Results Head and hip postural sway increased more in patients with CIDP than in healthy controls. MDD values reflecting hip strategies also increased more in patients than in controls. In the eyes closed condition MDD values in healthy subjects decreased but in patients remained unchanged. Discussion Sensori-motor impairment changes the balance between postural strategies that patients adopt to maintain upright quiet stance. Motor impairment leads to hip postural strategy overweight (eyes open), and prevents strategy re-balancing when the sensory context predominantly relies on proprioceptive input (eyes closed). PMID:26977594

Haptic cues for orientation and postural control in sighted and blind individuals

NASA Technical Reports Server (NTRS)

Jeka, J. J.; Easton, R. D.; Bentzen, B. L.; Lackner, J. R.

1996-01-01

Haptic cues from fingertip contact with a stable surface attenuate body sway in subjects even when the contact forces are too small to provide physical support of the body. We investigated how haptic cues derived from contact of a cane with a stationary surface at low force levels aids postural control in sighted and congenitally blind individuals. Five sighted (eyes closed) and five congenitally blind subjects maintained a tandem Romberg stance in five conditions: (1) no cane; (2,3) touch contact (< 2 N of applied force) while holding the cane in a vertical or slanted orientation; and (4,5) force contact (as much force as desired) in the vertical and slanted orientations. Touch contact of a cane at force levels below those necessary to provide significant physical stabilization was as effective as force contact in reducing postural sway in all subjects, compared to the no-cane condition. A slanted cane was far more effective in reducing postural sway than was a perpendicular cane. Cane use also decreased head displacement of sighted subjects far more than that of blind subjects. These results suggest that head movement control is linked to postural control through gaze stabilization reflexes in sighted subjects; such reflexes are absent in congenitally blind individuals and may account for their higher levels of head displacement.

Acute effects of head-down tilt and hypoxia on modulators of fluid homeostasis

NASA Technical Reports Server (NTRS)

Whitson, P. A.; Cintron, N. M.; Pietrzyk, R. A.; Scotto, P.; Loeppky, J. A.

1994-01-01

In an effort to understand the interaction between acute postural fluid shifts and hypoxia on hormonal regulation of fluid homeostasis, the authors measured the responses to head-down tilt with and without acute exposure to normobaric hypoxia. Plasma atrial natriuretic peptide (ANP), cyclic guanosine monophosphate (cGMP), cyclic adenosine monophosphate (cAMP), plasma aldosterone (ALD), and plasma renin activity (PRA) were measured in six healthy male volunteers who were exposed to a head-down tilt protocol during normoxia and hypoxia. The tilt protocol consisted of a 17 degrees head-up phase (30 minutes), a 28 degrees head-down phase (1 hour), and a 17 degrees head-up recovery period (2 hours, with the last hour normoxic in both experiments). Altitude equivalent to 14,828 ft was simulated by having the subjects breathe an inspired gas mixture with 13.9% oxygen. The results indicate that the postural fluid redistribution associated with a 60-minute head-down tilt induces the release of ANP and cGMP during both hypoxia and normoxia. Hypoxia increased cGMP, cAMP, ALD, and PRA throughout the protocol and significantly potentiated the increase in cGMP during head-down tilt. Hypoxia had no overall effect on the release of ANP, but appeared to attenuate the increase with head-down tilt. This study describes the acute effects of hypoxia on the endocrine response during fluid redistribution and suggests that the magnitude, but not the direction, of these changes with posture is affected by hypoxia.

Interhemispheric difference of pallidal local field potential activity in cervical dystonia.

PubMed

Lee, Jung Ryun; Kiss, Zelma H T

2014-03-01

Cervical dystonia (CD) produces involuntary neck muscle contractions that result in abnormal and often asymmetrical postures of the head and neck. Basal ganglia oscillatory activity in the 3-12 Hz band correlating with involuntary muscle activity suggests a role in the pathophysiology of primary dystonia. Despite the asymmetrical postures seen with CD, no comparison of interhemispheric differences of pallidal local field potential (LFP) activity has been reported. The aim of this study was to examine the interhemispheric differences of LFP power in globus pallidus interna (GPi) in CD patients and compare these with their predominant head excursion identified as torticollis, laterocollis and retrocollis. LFPs were recorded from bilateral GPi in 11 patients with CD using microelectrodes during deep brain stimulation surgery. LFP power was measured in right and left GPi separately. The mean percentage of total GPi LFP power in 4-30 Hz frequency band on each brain side was determined and related to their predominant CD symptoms. Interhemispheric difference in the mean percentage of LFP power in 4-12 Hz and 13-30 Hz band frequencies was found in patients with torticollis and laterocollis regardless of excursion direction. However, patients with retrocollis did not show interhemispheric difference in LFP activity in any band frequency. Interhemispheric differences in synchronisation of pallidal LFP activity in 4-12 Hz and 13-30 Hz bands are related to the CD clinical condition, suggesting that these frequencies are important in the pathophysiology of dystonia.

Central vestibular syndrome in a red fox (Vulpes vulpes) with presumptive right caudal cerebral artery ischemic infarct and prevalent midbrain involvement.

PubMed

Ricciardi, Mario; Gernone, Floriana; Simone, Antonio De; Giannuzzi, Pasquale

2017-01-01

A wild young male red fox ( Vulpes vulpes ) was found in the mountainous hinterland of Rome (Italy) with a heavily depressed mental status and unresponsive to the surrounding environment. Neurological examination revealed depression, left circling, right head tilt, ventromedial positional strabismus and decreased postural reactions on the left side. Neurological abnormalities were suggestive of central vestibular syndrome. Two consecutive MRIs performed with 30 days interval were compatible with lacunar ischemic infarct in the territory of right caudal cerebral artery and its collateral branches. The lesion epicentre was in the right periaqueductal portion of the rostral mesencephalic tegmentum. Neuroanatomical and neurophysiological correlation between lesion localization and clinical presentation are discussed.

Central vestibular syndrome in a red fox (Vulpes vulpes) with presumptive right caudal cerebral artery ischemic infarct and prevalent midbrain involvement

PubMed Central

Ricciardi, Mario; Gernone, Floriana; Simone, Antonio De; Giannuzzi, Pasquale

2017-01-01

A wild young male red fox (Vulpes vulpes) was found in the mountainous hinterland of Rome (Italy) with a heavily depressed mental status and unresponsive to the surrounding environment. Neurological examination revealed depression, left circling, right head tilt, ventromedial positional strabismus and decreased postural reactions on the left side. Neurological abnormalities were suggestive of central vestibular syndrome. Two consecutive MRIs performed with 30 days interval were compatible with lacunar ischemic infarct in the territory of right caudal cerebral artery and its collateral branches. The lesion epicentre was in the right periaqueductal portion of the rostral mesencephalic tegmentum. Neuroanatomical and neurophysiological correlation between lesion localization and clinical presentation are discussed. PMID:28717604

Classification of postural profiles among mouth-breathing children by learning vector quantization.

PubMed

Mancini, F; Sousa, F S; Hummel, A D; Falcão, A E J; Yi, L C; Ortolani, C F; Sigulem, D; Pisa, I T

2011-01-01

Mouth breathing is a chronic syndrome that may bring about postural changes. Finding characteristic patterns of changes occurring in the complex musculoskeletal system of mouth-breathing children has been a challenge. Learning vector quantization (LVQ) is an artificial neural network model that can be applied for this purpose. The aim of the present study was to apply LVQ to determine the characteristic postural profiles shown by mouth-breathing children, in order to further understand abnormal posture among mouth breathers. Postural training data on 52 children (30 mouth breathers and 22 nose breathers) and postural validation data on 32 children (22 mouth breathers and 10 nose breathers) were used. The performance of LVQ and other classification models was compared in relation to self-organizing maps, back-propagation applied to multilayer perceptrons, Bayesian networks, naive Bayes, J48 decision trees, k, and k-nearest-neighbor classifiers. Classifier accuracy was assessed by means of leave-one-out cross-validation, area under ROC curve (AUC), and inter-rater agreement (Kappa statistics). By using the LVQ model, five postural profiles for mouth-breathing children could be determined. LVQ showed satisfactory results for mouth-breathing and nose-breathing classification: sensitivity and specificity rates of 0.90 and 0.95, respectively, when using the training dataset, and 0.95 and 0.90, respectively, when using the validation dataset. The five postural profiles for mouth-breathing children suggested by LVQ were incorporated into application software for classifying the severity of mouth breathers' abnormal posture.

Cervical sensorimotor control in idiopathic cervical dystonia: A cross-sectional study.

PubMed

De Pauw, Joke; Mercelis, Rudy; Hallemans, Ann; Michiels, Sarah; Truijen, Steven; Cras, Patrick; De Hertogh, Willem

2017-09-01

Patients with idiopathic adult-onset cervical dystonia (CD) experience an abnormal head posture and involuntary muscle contractions. Although the exact areas affected in the central nervous system remain uncertain, impaired functions in systems stabilizing the head and neck are apparent such as the somatosensory and sensorimotor integration systems. The aim of the study is to investigate cervical sensorimotor control dysfunction in patients with CD. Cervical sensorimotor control was assessed by a head repositioning task in 24 patients with CD and 70 asymptomatic controls. Blindfolded participants were asked to reposition their head to a previously memorized neutral head position (NHP) following an active movement (flexion, extension, left, and right rotation). The repositioning error (joint position error, JPE) was registered via 3D motion analysis with an eight-camera infrared system (VICON ® T10). Disease-specific characteristics of all patients were obtained via the Tsui scale, Cervical Dystonia Impact Profile (CDIP-58), and Toronto Western Spasmodic Rating Scale. Patients with CD showed larger JPE than controls (mean difference of 1.5°, p  <   .006), and systematically 'overshoot', i.e. surpassed the NHP, whereas control subjects 'undershoot', i.e. fall behind the NHP. The JPE did not correlate with disease-specific characteristics. Cervical sensorimotor control is impaired in patients with CD. As cervical sensorimotor control can be trained, this might be a potential treatment option for therapy, adjuvant to botulinum toxin injections.

Medio-lateral postural instability in subjects with tinnitus.

PubMed

Kapoula, Zoi; Yang, Qing; Lê, Thanh-Thuan; Vernet, Marine; Berbey, Nolwenn; Orssaud, Christophe; Londero, Alain; Bonfils, Pierre

2011-01-01

Many patients show modulation of tinnitus by gaze, jaw or neck movements, reflecting abnormal sensorimotor integration, and interaction between various inputs. Postural control is based on multi-sensory integration (visual, vestibular, somatosensory, and oculomotor) and indeed there is now evidence that posture can also be influenced by sound. Perhaps tinnitus influences posture similarly to external sound. This study examines the quality of postural performance in quiet stance in patients with modulated tinnitus. Twenty-three patients with highly modulated tinnitus were selected in the ENT service. Twelve reported exclusively or predominately left tinnitus, eight right, and three bilateral. Eighteen control subjects were also tested. Subjects were asked to fixate a target at 40 cm for 51 s; posturography was performed with the platform (Technoconcept, 40 Hz) for both the eyes open and eyes closed conditions. For both conditions, tinnitus subjects showed abnormally high lateral body sway (SDx). This was corroborated by fast Fourrier Transformation (FFTx) and wavelet analysis. For patients with left tinnitus only, medio-lateral sway increased significantly when looking away from the center. Similarly to external sound stimulation, tinnitus could influence lateral sway by activating attention shift, and perhaps vestibular responses. Poor integration of sensorimotor signals is another possibility. Such abnormalities would be accentuated in left tinnitus because of the importance of the right cerebral cortex in processing both auditory-tinnitus eye position and attention.

Assisting People with Multiple Disabilities Actively Correct Abnormal Standing Posture with a Nintendo Wii Balance Board through Controlling Environmental Stimulation

ERIC Educational Resources Information Center

Shih, Ching-Hsiang; Shih, Ching-Tien; Chu, Chiung-Ling

2010-01-01

The latest researches adopted software technology turning the Nintendo Wii Balance Board into a high performance change of standing posture (CSP) detector, and assessed whether two persons with multiple disabilities would be able to control environmental stimulation using body swing (changing standing posture). This study extends Wii Balance Board…

Frontal and oblique crash tests of HIII 6-year-old child ATD using real-world, observed child passenger postures.

PubMed

Bohman, Katarina; Arbogast, Kristy B; Loeb, Helen; Charlton, Judith L; Koppel, Sjaan; Cross, Suzanne L

2018-02-28

The aim of this study was to evaluate the consequences of frontal and oblique crashes when positioning a Hybrid III (HIII) 6-year-old child anthropometric test device (ATD) using observed child passenger postures from a naturalistic driving study (NDS). Five positions for booster-seated children aged 4-7 years were selected, including one reference position according to the FMVSS 213 ATD seating protocol and 4 based on real-world observed child passenger postures from an NDS including 2 user positions with forward tilting torso and 2 that combined both forward and lateral inboard tilting of the torso. Seventeen sled tests were conducted in a mid-sized vehicle body at 64 km/h (European New Car Assessment Programme [Euro NCAP] Offset Deformable Barrier [ODB] pulse), in full frontal and oblique (15°) crash directions. The rear-seated HIII 6-year-old child ATD was restrained on a high-back booster seat. In 10 tests, the booster seat was also attached with a top tether. In the oblique tests, the ATD was positioned on the far side. Three camera views and ATD responses (head, neck, and chest) were analyzed. The shoulder belt slipped off the shoulder in all ATD positions in the oblique test configuration. In full frontal tests, the shoulder belt stayed on the shoulder in 3 out of 9 tests. Head acceleration and neck tension were decreased in the forward leaning positions; however, the total head excursion increased up to 210 mm compared to te reference position, due to belt slip-off and initial forward leaning position. These results suggest that real-world child passenger postures may contribute to shoulder belt slip-off and increased head excursion, thus increasing the risk of head injury. Restraint system development needs to include a wider range of sitting postures that children may choose, in addition to the specified postures of ATDs in seating test protocols, to ensure robust performance across diverse use cases. In addition, these tests revealed that the child ATD is limited in its ability to mimic real-world child passenger postures. There is a need to develop child human body models that may offer greater flexibility for these types of crash evaluations.

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

PubMed

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.

Evaluation of validity and reliability of a methodology for measuring human postural attitude and its relation to temporomandibular joint disorders

PubMed Central

Fernández, Ramón Fuentes; Carter, Pablo; Muñoz, Sergio; Silva, Héctor; Venegas, Gonzalo Hernán Oporto; Cantin, Mario; Ottone, Nicolás Ernesto

2016-01-01

INTRODUCTION Temporomandibular joint disorders (TMJDs) are caused by several factors such as anatomical, neuromuscular and psychological alterations. A relationship has been established between TMJDs and postural alterations, a type of anatomical alteration. An anterior position of the head requires hyperactivity of the posterior neck region and shoulder muscles to prevent the head from falling forward. This compensatory muscular function may cause fatigue, discomfort and trigger point activation. To our knowledge, a method for assessing human postural attitude in more than one plane has not been reported. Thus, the aim of this study was to design a methodology to measure the external human postural attitude in frontal and sagittal planes, with proper validity and reliability analyses. METHODS The variable postures of 78 subjects (36 men, 42 women; age 18–24 years) were evaluated. The postural attitudes of the subjects were measured in the frontal and sagittal planes, using an acromiopelvimeter, grid panel and Fox plane. RESULTS The method we designed for measuring postural attitudes had adequate reliability and validity, both qualitatively and quantitatively, based on Cohen’s Kappa coefficient (> 0.87) and Pearson’s correlation coefficient (r = 0.824, > 80%). CONCLUSION This method exhibits adequate metrical properties and can therefore be used in further research on the association of human body posture with skeletal types and TMJDs. PMID:26768173

Evaluation of validity and reliability of a methodology for measuring human postural attitude and its relation to temporomandibular joint disorders.

PubMed

Fuentes Fernández, Ramón; Carter, Pablo; Muñoz, Sergio; Silva, Héctor; Oporto Venegas, Gonzalo Hernán; Cantin, Mario; Ottone, Nicolás Ernesto

2016-04-01

Temporomandibular joint disorders (TMJDs) are caused by several factors such as anatomical, neuromuscular and psychological alterations. A relationship has been established between TMJDs and postural alterations, a type of anatomical alteration. An anterior position of the head requires hyperactivity of the posterior neck region and shoulder muscles to prevent the head from falling forward. This compensatory muscular function may cause fatigue, discomfort and trigger point activation. To our knowledge, a method for assessing human postural attitude in more than one plane has not been reported. Thus, the aim of this study was to design a methodology to measure the external human postural attitude in frontal and sagittal planes, with proper validity and reliability analyses. The variable postures of 78 subjects (36 men, 42 women; age 18-24 years) were evaluated. The postural attitudes of the subjects were measured in the frontal and sagittal planes, using an acromiopelvimeter, grid panel and Fox plane. The method we designed for measuring postural attitudes had adequate reliability and validity, both qualitatively and quantitatively, based on Cohen's Kappa coefficient (> 0.87) and Pearson's correlation coefficient (r = 0.824, > 80%). This method exhibits adequate metrical properties and can therefore be used in further research on the association of human body posture with skeletal types and TMJDs. Copyright © Singapore Medical Association.

Motion sickness elicited by passive rotation in squirrel monkeys

NASA Technical Reports Server (NTRS)

Daunton, Nancy G.; Fox, Robert A.

1991-01-01

Current theory and recent evidence suggest that motion sickness occurs under conditions of sensory input in which the normal motor programs for producing eye, head, and body movements are not functionally effective, i.e. under conditions in which there are difficulties in maintaining posture and controlling eye movements. Conditions involving conflicting or inconsistent visual-vestibular (VV) stimulation should thus result in greater sickness rates since the existing motor programs do not produce effective control of eye-head-body movements under such conditions. It is felt that the relationship of postural control to motion sickness is an important one and one often overlooked. The results are reported which showed that when postural requirements were minimized by fully restraining squirrel monkeys during hypogravity parabolic flight, no animals became motion sick, but over 80 percent of the same 11 animals became sick if they were unrestrained and maintained control of their posture.

Responses evoked by a vestibular implant providing chronic stimulation.

PubMed

Thompson, Lara A; Haburcakova, Csilla; Gong, Wangsong; Lee, Daniel J; Wall, Conrad; Merfeld, Daniel M; Lewis, Richard F

2012-01-01

Patients with bilateral vestibular loss experience dehabilitating visual, perceptual, and postural difficulties, and an implantable vestibular prosthesis that could improve these symptoms would be of great benefit to these patients. In previous work, we have shown that a one-dimensional, unilateral canal prosthesis can improve the vestibulooccular reflex (VOR) in canal-plugged squirrel monkeys. In addition to the VOR, the potential effects of a vestibular prosthesis on more complex, highly integrative behaviors, such as the perception of head orientation and posture have remained unclear. We tested a one-dimensional, unilateral prosthesis in a rhesus monkey with bilateral vestibular loss and found that chronic electrical stimulation partially restored the compensatory VOR and also that percepts of head orientation relative to gravity were improved. However, the one-dimensional prosthetic stimulation had no clear effect on postural stability during quiet stance, but sway evoked by head-turns was modestly reduced. These results suggest that not only can the implementation of a vestibular prosthesis provide partial restitution of VOR but may also improve perception and posture in the presence of bilateral vestibular hypofunction (BVH). In this review, we provide an overview of our previous and current work directed towards the eventual clinical implementation of an implantable vestibular prosthesis.

Assessing Sensorimotor Function Following ISS with Computerized Dynamic Posturography.

PubMed

Wood, Scott J; Paloski, William H; Clark, Jonathan B

2015-12-01

Postflight postural ataxia reflects both the control strategies adopted for movement in microgravity and the direct effects of deconditioning. Computerized dynamic posturography (CDP) has been used during the first decade of the International Space Station (ISS) expeditions to quantify the initial postflight decrements and recovery of postural stability. The CDP data were obtained on 37 crewmembers as part of their pre- and postflight medical examinations. Sensory organization tests evaluated the ability to make effective use of (or suppress inappropriate) visual, vestibular, and somatosensory information for balance control. This report focuses on eyes closed conditions with either a fixed or sway-referenced base of support, with the head erect or during pitch-head tilts (± 20° at 0.33 Hz). Equilibrium scores were derived from peak-to-peak anterior-posterior sway. Motor-control tests were also used to evaluate a crewmember's ability to automatically recover from unexpected support-surface perturbations. The standard Romberg condition was the least sensitive. Dynamic head tilts led to increased incidence of falls and revealed significantly longer recovery than head-erect conditions. Improvements in postflight postural performance during the later expeditions may be attributable to higher preflight baselines and/or advanced exercise capabilities aboard the ISS. The diagnostic assessment of postural instability is more pronounced during unstable-support conditions requiring active head movements. In addition to supporting return-to-duty decisions by flight surgeons, the CDP provides a standardized sensorimotor measure that can be used to evaluate the effectiveness of countermeasures designed to either minimize deconditioning on orbit or promote reconditioning upon return to Earth.

Direction-Specific Impairments in Cervical Range of Motion in Women with Chronic Neck Pain: Influence of Head Posture and Gravitationally Induced Torque.

PubMed

Rudolfsson, Thomas; Björklund, Martin; Svedmark, Åsa; Srinivasan, Divya; Djupsjöbacka, Mats

2017-01-01

Cervical range of motion (ROM) is commonly assessed in clinical practice and research. In a previous study we decomposed active cervical sagittal ROM into contributions from lower and upper levels of the cervical spine and found level- and direction-specific impairments in women with chronic non-specific neck pain. The present study aimed to validate these results and investigate if the specific impairments can be explained by the neutral posture (defining zero flexion/extension) or a movement strategy to avoid large gravitationally induced torques on the cervical spine. Kinematics of the head and thorax was assessed in sitting during maximal sagittal cervical flexion/extension (high torque condition) and maximal protraction (low torque condition) in 120 women with chronic non-specific neck pain and 40 controls. We derived the lower and upper cervical angles, and the head centre of mass (HCM), from a 3-segment kinematic model. Neutral head posture was assessed using a standardized procedure. Previous findings of level- and direction-specific impairments in neck pain were confirmed. Neutral head posture was equal between groups and did not explain the direction-specific impairments. The relative magnitude of group difference in HCM migration did not differ between high and low torques conditions, lending no support for our hypothesis that impairments in sagittal ROM are due to torque avoidance behaviour. The direction- and level-specific impairments in cervical sagittal ROM can be generalised to the population of women with non-specific neck pain. Further research is necessary to clarify if torque avoidance behaviour can explain the impairments.

Craniocervical Posture in Patients with Obstructive Sleep Apnea

PubMed Central

Piccin, Chaiane Facco; Pozzebon, Daniela; Scapini, Fabricio; Corrêa, Eliane Castilhos Rodrigues

2016-01-01

Introduction  Obstructive Sleep Apnea (OSA) is characterized by repeated episodes of upper airway obstruction during sleep. Objective  The objective of this study is to verify the craniofacial characteristics and craniocervical posture of OSA and healthy subjects, determining possible relationships with the apnea/hypopnea index (AHI). Methods  This case-control study evaluated 21 subjects with OSA, who comprised the OSA group (OSAG), and 21 healthy subjects, who constituted the control group (CG). Cephalometry analyzed head posture measurements, craniofacial measurements, and air space. Head posture was also assessed by means of photogrammetry. Results  The groups were homogeneous regarding gender (12 men and 9 women in each group), age (OSAG = 41.86 ± 11.26 years; GC = 41.19 ± 11.20 years), and body mass index (OSAG = 25.65 ± 2.46 kg/m2; CG = 24.72 ± 3.01 kg/m2). We found significant differences between the groups, with lower average pharyngeal space and greater distance between the hyoid bone and the mandibular plane in OSAG, when compared with CG. A positive correlation was found between higher head hyperextension and head anteriorization, with greater severity of OSA as assessed by AHI. Conclusion  OSAG subjects showed changes in craniofacial morphology, with lower average pharyngeal space and greater distance from the hyoid bone to the mandibular plane, as compared with healthy subjects. Moreover, in OSA subjects, the greater the severity of OSA, the greater the head hyperextension and anteriorization. PMID:27413397

Spatial Orientation and Balance Control Changes Induced by Altered Gravito-Inertial Force Vectors

NASA Technical Reports Server (NTRS)

Kaufman, Galen D.; Wood, Scott J.; Gianna, Claire C.; Black, F. Owen; Paloski, William H.; Dawson, David L. (Technical Monitor)

1999-01-01

Seventeen healthy and eight vestibular deficient subjects were exposed to an interaural centripetal acceleration of 1 G (resultant 45 deg roll tilt of 1.4 G) on a 0.8 meter radius centrifuge for a period of 90 minutes in the dark. The subjects sat with head fixed upright, except every 4 of 10 minutes when instructed to rotate their head so that their nose and eyes pointed towards a visual point switched on every 3 to 5 seconds at random places (within +/- 30 deg) in the Earth horizontal plane. Motion sickness caused some subjects to limit their head movements during significant portions of the 90 minute period, and led three normal subjects to stop the test earlier. Eye movements, including directed saccades for subjective Earth- and head-referenced planes, were recorded before, during, and immediately after centrifugation using electro-oculography. Postural stability measurements were made before and within ten minutes after centrifugation. In normal subjects, postural sway and multisegment body kinematics were gathered during an eyes-closed head movement cadence (sway-referenced support platform), and in response to translational/rotational platform perturbations. A significant increase in postural sway, segmental motion amplitude and hip frequency was observed after centrifugation. This effect was short-lived, with a recovery time of several postural test trials. There were also asymmetries in the direction of post-centrifugation center of sway and head tilt which depended on the subject's orientation during the centrifugation adaptation period (left ear or right ear out). To delineate the effect of the magnitude of the gravito-inertial vector versus its direction during the adaptive centrifugation period, we tilted eight normal subjects in the roll axis at a 45 deg angle in the dark for 90 minutes without rotational motion. Their postural responses did not change following the period of tilt. Based on verbal reports, normal subjects overestimated roll-tilt during 90 minutes of both tilt and centrifugation stimuli. Subjective estimates of head-horizontal, provided by directed saccades, revealed significant errors after approximately 30 minutes that tended to increase only in the group who underwent centrifugation. Immediately after centrifugation, subjects reported feeling tilted on average 10 degrees in the opposite direction, which was in agreement with the direction of their earth-directed saccades. In vestibular deficient (VD) subjects, postural sway was measured using a sway-referenced or earth-fixed support surface, and with or without a head movement sequence. 'Me protocol was selected for each patient during baseline testing, and corresponded to the most challenging condition in which the patient was able to maintain balance with eyes closed. Bilaterally VD subjects showed no postural decrement after centrifugation, while unilateral VD subjects had varying degrees of decrement. Unilateral VD subjects were tested twice; they underwent centrifugation both with right ear out and left ear out. Their post-centrifuation center of sway shifted at right angles depending on the centrifuge GIF orientation. Bilateral VD subjects bad shifts as well, but no consistent directional trend. VD subjects underestimated roll-tilt during centrifugation, These results suggest that orientation of the gravito-inertial vector and its magnitude arc both used by the central nervous system for calibration of multiple orientation systems. A change in the background gravito-inertial force (otolith input) can rapidly initiate postural and perceptual adaptation in several sensorimotor systems, independent of a structured visual surround.

A dystonia-like movement disorder with brain and spinal neuronal defects is caused by mutation of the mouse laminin β1 subunit, Lamb1

PubMed Central

Liu, Yi Bessie; Tewari, Ambika; Salameh, Johnny; Arystarkhova, Elena; Hampton, Thomas G; Brashear, Allison; Ozelius, Laurie J; Khodakhah, Kamran; Sweadner, Kathleen J

2015-01-01

A new mutant mouse (lamb1t) exhibits intermittent dystonic hindlimb movements and postures when awake, and hyperextension when asleep. Experiments showed co-contraction of opposing muscle groups, and indicated that symptoms depended on the interaction of brain and spinal cord. SNP mapping and exome sequencing identified the dominant causative mutation in the Lamb1 gene. Laminins are extracellular matrix proteins, widely expressed but also known to be important in synapse structure and plasticity. In accordance, awake recording in the cerebellum detected abnormal output from a circuit of two Lamb1-expressing neurons, Purkinje cells and their deep cerebellar nucleus targets, during abnormal postures. We propose that dystonia-like symptoms result from lapses in descending inhibition, exposing excess activity in intrinsic spinal circuits that coordinate muscles. The mouse is a new model for testing how dysfunction in the CNS causes specific abnormal movements and postures. DOI: http://dx.doi.org/10.7554/eLife.11102.001 PMID:26705335

Simulation of the effects of different pilot helmets on neck loading during air combat.

PubMed

Mathys, R; Ferguson, S J

2012-09-21

New generation pilot helmets with mounted devices enhance the capabilities of pilots substantially. However, the additional equipment increases the helmet weight and shifts its center of mass forward. Two helmets with different mass properties were modeled to simulate their effects on the pilot's neck. A musculoskeletal computer model was used, with the methods of inverse dynamics and static optimization, to compute the muscle activations and joint reaction forces for a given range of quasi-static postures at various accelerations experienced during air combat. Head postures which induce much higher loads on the cervical spine than encountered in a neutral position could be identified. The increased weight and the forward shift of the center of mass of a new generation helmet lead to higher muscle activations and higher joint reaction loads over a wide range of head and neck movements. The muscle activations required to balance the head and neck in extreme postures increased the compressive force at the T1-C7 level substantially, while in a neutral posture the muscle activations remained low. The lateral neck muscles can reach activations of 100% and cause compressive joint forces up to 1100N during extensive rotations and extensions at high 'vertical' accelerations (Gz). The calculated values have to be interpreted with care as the model has not been validated. Nevertheless, this systematic analysis could separate the effects of head posture, acceleration and helmet mass on neck loading. More reliable data about mass properties and muscle morphometry with a more detailed motion analysis would help to refine the existing model. Copyright © 2012 Elsevier Ltd. All rights reserved.

Head and cervical spine posture in behaving rats: implications for modeling human conditions involving the head and cervical spine.

PubMed

Griffin, C; Choong, W Y; Teh, W; Buxton, A J; Bolton, P S

2015-02-01

The aim of this study was to define the temporal and spatial (postural) characteristics of the head and cervical vertebral column (spine) of behaving rats in order to better understand their suitability as a model to study human conditions involving the head and neck. Time spent in each of four behavioral postures was determined from video tape recordings of rats (n = 10) in the absence and presence of an intruder rat. Plain film radiographic examination of a subset of these rats (n = 5) in each of these postures allowed measurement of head and cervical vertebral column positions adopted by the rats. When single they were quadruped or crouched most (∼80%) of the time and bipedal either supported or free standing for only ∼10% of the time. The introduction of an intruder significantly (P < 0.0001) reduced the proportion of time rats spent quadruped (median, from 71% to 47%) and bipedal free standing (median, from 2.9% to 0.4%). The cervical spine was orientated (median, 25-75 percentile) near vertical (18.8°, 4.2°-30.9°) when quadruped, crouched (15.4°, 7.6°-69.3°) and bipedal supported (10.5°, 4.8°-22.6°) but tended to be less vertical oriented when bipedal free standing (25.9°, 7.7°-39.3°). The range of head positions relative to the cervical spine was largest when crouched (73.4°) and smallest when erect free standing (17.7°). This study indicates that, like humans, rats have near vertical orientated cervical vertebral columns but, in contrast to humans, they displace their head in space by movements at both the cervico-thoracic junction and the cranio-cervical regions. © 2014 Wiley Periodicals, Inc.

Global Body Posture Evaluation in Patients with Temporomandibular Joint Disorder

PubMed Central

Saito, Eliza Tiemi; Akashi, Paula Marie Hanai; de Camargo Neves Sacco, Isabel

2009-01-01

AIM: To identify the relationship between anterior disc displacement and global posture (plantar arches, lower limbs, shoulder and pelvic girdle, vertebral spine, head and mandibles). Common signs and symptoms of anterior disc displacement were also identified. INTRODUCTION: Global posture deviations cause body adaptation and realignment, which may interfere with the organization and function of the temporomandibular joint. METHODS : Global posture evaluation was performed in a group of 10 female patients (20 to 30 years of age) with temporomandibular joint disc displacement and in a control group of 16 healthy female volunteers matched for age, weight and height. Anterior disc displacement signs, symptoms and the presence of parafunctional habits were also identified through interview. RESULTS: Patients with disc displacement showed a higher incidence of pain in the temporomandibular joint area, but there were no differences in parafunctional habits between the groups. In the disc displacement group, postural deviations were found in the pelvis (posterior rotation), lumbar spine (hyperlordosis), thoracic spine (rectification), head (deviation to the right) and mandibles (deviation to the left with open mouth). There were no differences in the longitudinal plantar arches between the groups. CONCLUSION: Our results suggest a close relationship between body posture and temporomandibular disorder, though it is not possible to determine whether postural deviations are the cause or the result of the disorder. Hence, postural evaluation could be an important component in the overall approach to providing accurate prevention and treatment in the management of patients with temporomandibular disorder. PMID:19142549

Effect of table top slope and height on body posture and muscular activity pattern.

PubMed

Hassaïne, M; Hamaoui, A; Zanone, P-G

2015-04-01

The objective of this study was to assess the effect of table top slope and height on body posture and muscular activity pattern. Twelve asymptomatic participants performed a 5-min reading task while sitting, in six experimental conditions manipulating the table top slope (20° backward slope, no slope) and its height (low, medium, up). EMGs recordings were taken on 9 superficial muscles located at the trunk and shoulder level, and the angular positions of the head, trunk and pelvis were assessed using an inertial orientation system. Results revealed that the sloping table top was associated with a higher activity of deltoideus pars clavicularis (P<0.05) and a smaller flexion angle of the head (P<0.05). A tentative conclusion is that a sloping table top induces a more erect posture of the head and the neck, but entails an overload of the shoulder, which might be harmful on the long run. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

State-dependent sensorimotor processing: gaze and posture stability during simulated flight in birds.

PubMed

McArthur, Kimberly L; Dickman, J David

2011-04-01

Vestibular responses play an important role in maintaining gaze and posture stability during rotational motion. Previous studies suggest that these responses are state dependent, their expression varying with the environmental and locomotor conditions of the animal. In this study, we simulated an ethologically relevant state in the laboratory to study state-dependent vestibular responses in birds. We used frontal airflow to simulate gliding flight and measured pigeons' eye, head, and tail responses to rotational motion in darkness, under both head-fixed and head-free conditions. We show that both eye and head response gains are significantly higher during flight, thus enhancing gaze and head-in-space stability. We also characterize state-specific tail responses to pitch and roll rotation that would help to maintain body-in-space orientation during flight. These results demonstrate that vestibular sensorimotor processing is not fixed but depends instead on the animal's behavioral state.

State-dependent sensorimotor processing: gaze and posture stability during simulated flight in birds

PubMed Central

McArthur, Kimberly L.

2011-01-01

Vestibular responses play an important role in maintaining gaze and posture stability during rotational motion. Previous studies suggest that these responses are state dependent, their expression varying with the environmental and locomotor conditions of the animal. In this study, we simulated an ethologically relevant state in the laboratory to study state-dependent vestibular responses in birds. We used frontal airflow to simulate gliding flight and measured pigeons′ eye, head, and tail responses to rotational motion in darkness, under both head-fixed and head-free conditions. We show that both eye and head response gains are significantly higher during flight, thus enhancing gaze and head-in-space stability. We also characterize state-specific tail responses to pitch and roll rotation that would help to maintain body-in-space orientation during flight. These results demonstrate that vestibular sensorimotor processing is not fixed but depends instead on the animal's behavioral state. PMID:21307332

Body posture in children with obesity - the relationship to physical activity (PA).

PubMed

Brzęk, Anna; Sołtys, Jacek; Gallert-Kopyto, Weronika; Gwizdek, Katarzyna; Plinta, Ryszard

2016-01-01

The modern world of electronic devices offers children and young people various forms of leisure activities, while reducing the need for natural movement, necessary for normal psychomotor development. Sedentary life contributes to an increased body weight and, thereby, to the development of body posture abnormalities. The aim of the study was to evaluate body posture, leisure activities, and the number of hours spent using electronic devices among children with obesity. The study involved 51 children with obesity (BMI above 95 percentile) - A group, and 69 children with normal body weight at the age of 9-13 years (10.98 ± 1.29) - B group (control). Body posture has been evaluated with the scoliometer, the digital inclinometer and the plumb line. The hump ratio has been calculated on the basis of SOSORT recommendations. Time spent in front of electronic devices based on a questionnaire results has also been calculated. Children with obesity have more body posture defects in the sagittal plane than children with normal z-scores (p<0.001). 46.8% of children in group A have distorted depth of the two curvatures of the spine. In the control group, the majority of deviations have been observed in the evaluation of the ATR (Angle Trunk Rotation) at the lumbar spine (p<0.05), while in group A, at the level of the thoracic spine (40.42% vs. 23.07%). Both groups of respondents use electronic devices at least 3 days a week (p>0.05). Obese children often use mobile devices, while children with normal body weight often use desktop equipment. Definitely more body posture abnormalities are found in the group of obese children. Children use electronic devices regardless of weight. It is worth to expand educational activities with programs that improve the quality of body posture through a daily change of abnormal patterns. © Polish Society for Pediatric Endocrinology and Diabetology.

Recent bed rest results and countermeasure development at NASA

NASA Technical Reports Server (NTRS)

Hargens, A. R.

1994-01-01

Bedrest studies of normal subjects provide opportunities to understand physiologic responses to supine posture and inactivity. Furthermore, head-down tilt has been a valuable procedure to investigate adaptation to microgravity and development of countermeasures to maintain the health and well-being of humans during space-flight. Recent bedrest experiments at NASA have ranged in duration from a few hours to 17 weeks. Acute studies of 6 degrees head-down tilt indicate that elevation of capillary blood pressure from 28 to 34 mm Hg and increased capillary perfusion in tissues of the head cause facial and intracranial edema. Intracranial pressure increases from 2 to 17 mm Hg going from upright posture to 6 degrees head-down tilt. Microvessels of the head have a low capacity to constrict and diminish local perfusion. Elevation of blood and tissue fluid pressures/flow in the head may also explain the higher headward bone density associated with long-term head-down tilt. These mechanistic studies of head-down tilt, along with a better understanding of the relative stresses involved with upright posture and lower body negative pressure, have facilitated development of suitable physiologic countermeasures to maintain astronaut health during microgravity. Presently no exercise hardware is available to provide a blood pressure gradient from head to feet in space. However, recent studies in our laboratory suggest that treadmill exercise using a graded lower-body compression suit and 100 mmHg lower body negative pressure provides equivalent or greater physiologic stress than similar upright exercise on Earth. Therefore, exercise within a lower body negative pressure chamber may provide a cost-effective and simple countermeasure to maintain the cardiovascular and neuro-musculoskeletal systems of astronauts during long-duration flight.

Forearm posture and mobility in quadrupedal dinosaurs.

PubMed

VanBuren, Collin S; Bonnan, Matthew

2013-01-01

Quadrupedality evolved four independent times in dinosaurs; however, the constraints associated with these transitions in limb anatomy and function remain poorly understood, in particular the evolution of forearm posture and rotational ability (i.e., active pronation and supination). Results of previous qualitative studies are inconsistent, likely due to an inability to quantitatively assess the likelihood of their conclusions. We attempt to quantify antebrachial posture and mobility using the radius bone because its morphology is distinct between extant sprawled taxa with a limited active pronation ability and parasagittal taxa that have an enhanced ability to actively pronate the manus. We used a sliding semi-landmark, outline-based geometric morphometric approach of the proximal radial head and a measurement of the angle of curvature of the radius in a sample of 189 mammals, 49 dinosaurs, 35 squamates, 16 birds, and 5 crocodilians. Our results of radial head morphology showed that quadrupedal ceratopsians, bipedal non-hadrosaurid ornithopods, and theropods had limited pronation/supination ability, and sauropodomorphs have unique radial head morphology that likely allowed limited rotational ability. However, the curvature of the radius showed that no dinosaurian clade had the ability to cross the radius about the ulna, suggesting parallel antebrachial elements for all quadrupedal dinosaurs. We conclude that the bipedal origins of all quadrupedal dinosaur clades could have allowed for greater disparity in forelimb posture than previously appreciated, and future studies on dinosaur posture should not limit their classifications to the overly simplistic extant dichotomy.

Forearm Posture and Mobility in Quadrupedal Dinosaurs

PubMed Central

VanBuren, Collin S.; Bonnan, Matthew

2013-01-01

Quadrupedality evolved four independent times in dinosaurs; however, the constraints associated with these transitions in limb anatomy and function remain poorly understood, in particular the evolution of forearm posture and rotational ability (i.e., active pronation and supination). Results of previous qualitative studies are inconsistent, likely due to an inability to quantitatively assess the likelihood of their conclusions. We attempt to quantify antebrachial posture and mobility using the radius bone because its morphology is distinct between extant sprawled taxa with a limited active pronation ability and parasagittal taxa that have an enhanced ability to actively pronate the manus. We used a sliding semi-landmark, outline-based geometric morphometric approach of the proximal radial head and a measurement of the angle of curvature of the radius in a sample of 189 mammals, 49 dinosaurs, 35 squamates, 16 birds, and 5 crocodilians. Our results of radial head morphology showed that quadrupedal ceratopsians, bipedal non-hadrosaurid ornithopods, and theropods had limited pronation/supination ability, and sauropodomorphs have unique radial head morphology that likely allowed limited rotational ability. However, the curvature of the radius showed that no dinosaurian clade had the ability to cross the radius about the ulna, suggesting parallel antebrachial elements for all quadrupedal dinosaurs. We conclude that the bipedal origins of all quadrupedal dinosaur clades could have allowed for greater disparity in forelimb posture than previously appreciated, and future studies on dinosaur posture should not limit their classifications to the overly simplistic extant dichotomy. PMID:24058633

A review of wearable technology in medicine.

PubMed

Iqbal, Mohammed H; Aydin, Abdullatif; Brunckhorst, Oliver; Dasgupta, Prokar; Ahmed, Kamran

2016-10-01

With rapid advances in technology, wearable devices have evolved and been adopted for various uses, ranging from simple devices used in aiding fitness to more complex devices used in assisting surgery. Wearable technology is broadly divided into head-mounted displays and body sensors. A broad search of the current literature revealed a total of 13 different body sensors and 11 head-mounted display devices. The latter have been reported for use in surgery (n = 7), imaging (n = 3), simulation and education (n = 2) and as navigation tools (n = 1). Body sensors have been used as vital signs monitors (n = 9) and for posture-related devices for posture and fitness (n = 4). Body sensors were found to have excellent functionality in aiding patient posture and rehabilitation while head-mounted displays can provide information to surgeons to while maintaining sterility during operative procedures. There is a potential role for head-mounted wearable technology and body sensors in medicine and patient care. However, there is little scientific evidence available proving that the application of such technologies improves patient satisfaction or care. Further studies need to be conducted prior to a clear conclusion. © The Royal Society of Medicine.

Effective seat-to-head transmissibility in whole-body vibration: Effects of posture and arm position

NASA Astrophysics Data System (ADS)

Rahmatalla, Salam; DeShaw, Jonathan

2011-12-01

Seat-to-head transmissibility is a biomechanical measure that has been widely used for many decades to evaluate seat dynamics and human response to vibration. Traditionally, transmissibility has been used to correlate single-input or multiple-input with single-output motion; it has not been effectively used for multiple-input and multiple-output scenarios due to the complexity of dealing with the coupled motions caused by the cross-axis effect. This work presents a novel approach to use transmissibility effectively for single- and multiple-input and multiple-output whole-body vibrations. In this regard, the full transmissibility matrix is transformed into a single graph, such as those for single-input and single-output motions. Singular value decomposition and maximum distortion energy theory were used to achieve the latter goal. Seat-to-head transmissibility matrices for single-input/multiple-output in the fore-aft direction, single-input/multiple-output in the vertical direction, and multiple-input/multiple-output directions are investigated in this work. A total of ten subjects participated in this study. Discrete frequencies of 0.5-16 Hz were used for the fore-aft direction using supported and unsupported back postures. Random ride files from a dozer machine were used for the vertical and multiple-axis scenarios considering two arm postures: using the armrests or grasping the steering wheel. For single-input/multiple-output, the results showed that the proposed method was very effective in showing the frequencies where the transmissibility is mostly sensitive for the two sitting postures and two arm positions. For multiple-input/multiple-output, the results showed that the proposed effective transmissibility indicated higher values for the armrest-supported posture than for the steering-wheel-supported posture.

Decreased postural control in people with moderate hearing loss

PubMed Central

Thomas, Ewan; Martines, Francesco; Bianco, Antonino; Messina, Giuseppe; Giustino, Valerio; Zangla, Daniele; Iovane, Angelo; Palma, Antonio

2018-01-01

Abstract Balance is a complex process that involves multiple sensory integrations. The auditory, visual, and vestibular systems are the main contributors. Hearing loss or hearing impairment may induce inappropriate postural strategies that could affect balance and therefore increase the risk of falling. The aim of this study was to understand whether hearing loss could influence balance, cervical posture, and muscle activation in the cervical region. Thirteen patients (61 ± 13 years; 161.8 ± 11.0 cm; 70.5 ± 15.9 kg) with moderate hearing loss (Right ear −60 ± 21 dB; Left ear −61 ± 24 dB) underwent: an audiometric examination, a postural examination (with open and closed eyes) through a stabilometric platform, a cervical ROM examination through a head accelerometer, and a sternocleidomastoid electromyography (EMG) examination. A linear regression analysis has shown a regression coefficient (R2) 0.76 and 0.69 between hearing loss and the posturographic parameters, on the sagittal sway, with open and closed eyes, respectively. The combination of frontal and sagittal sway is able to explain up to 84% of the variance of the audiometric assessment. No differences were found between right and left hemibody between the audiometric, posturographic, cervical ROM parameters, and in EMG amplitude. ROM and EMG parameters have not shown any significant associations with hearing loss, for both right and left head rotation. Hearing loss is associated to increased posturographic measures, especially the sagittal sway, underlining a reduced postural control in people with hearing impairments. No association was found between the heads posture and neck activation with hearing loss. Hearing loss may be associated with an increased risk of falls. PMID:29620637

Decreased postural control in people with moderate hearing loss.

PubMed

Thomas, Ewan; Martines, Francesco; Bianco, Antonino; Messina, Giuseppe; Giustino, Valerio; Zangla, Daniele; Iovane, Angelo; Palma, Antonio

2018-04-01

Balance is a complex process that involves multiple sensory integrations. The auditory, visual, and vestibular systems are the main contributors. Hearing loss or hearing impairment may induce inappropriate postural strategies that could affect balance and therefore increase the risk of falling.The aim of this study was to understand whether hearing loss could influence balance, cervical posture, and muscle activation in the cervical region.Thirteen patients (61 ± 13 years; 161.8 ± 11.0 cm; 70.5 ± 15.9 kg) with moderate hearing loss (Right ear -60 ± 21 dB; Left ear -61 ± 24 dB) underwent: an audiometric examination, a postural examination (with open and closed eyes) through a stabilometric platform, a cervical ROM examination through a head accelerometer, and a sternocleidomastoid electromyography (EMG) examination.A linear regression analysis has shown a regression coefficient (R) 0.76 and 0.69 between hearing loss and the posturographic parameters, on the sagittal sway, with open and closed eyes, respectively. The combination of frontal and sagittal sway is able to explain up to 84% of the variance of the audiometric assessment. No differences were found between right and left hemibody between the audiometric, posturographic, cervical ROM parameters, and in EMG amplitude. ROM and EMG parameters have not shown any significant associations with hearing loss, for both right and left head rotation.Hearing loss is associated to increased posturographic measures, especially the sagittal sway, underlining a reduced postural control in people with hearing impairments. No association was found between the heads posture and neck activation with hearing loss. Hearing loss may be associated with an increased risk of falls.

Direction-Specific Impairments in Cervical Range of Motion in Women with Chronic Neck Pain: Influence of Head Posture and Gravitationally Induced Torque

PubMed Central

Björklund, Martin; Svedmark, Åsa; Srinivasan, Divya; Djupsjöbacka, Mats

2017-01-01

Background Cervical range of motion (ROM) is commonly assessed in clinical practice and research. In a previous study we decomposed active cervical sagittal ROM into contributions from lower and upper levels of the cervical spine and found level- and direction-specific impairments in women with chronic non-specific neck pain. The present study aimed to validate these results and investigate if the specific impairments can be explained by the neutral posture (defining zero flexion/extension) or a movement strategy to avoid large gravitationally induced torques on the cervical spine. Methods Kinematics of the head and thorax was assessed in sitting during maximal sagittal cervical flexion/extension (high torque condition) and maximal protraction (low torque condition) in 120 women with chronic non-specific neck pain and 40 controls. We derived the lower and upper cervical angles, and the head centre of mass (HCM), from a 3-segment kinematic model. Neutral head posture was assessed using a standardized procedure. Findings Previous findings of level- and direction-specific impairments in neck pain were confirmed. Neutral head posture was equal between groups and did not explain the direction-specific impairments. The relative magnitude of group difference in HCM migration did not differ between high and low torques conditions, lending no support for our hypothesis that impairments in sagittal ROM are due to torque avoidance behaviour. Interpretation The direction- and level-specific impairments in cervical sagittal ROM can be generalised to the population of women with non-specific neck pain. Further research is necessary to clarify if torque avoidance behaviour can explain the impairments. PMID:28099504

Scapular Bracing and Alteration of Posture and Muscle Activity in Overhead Athletes With Poor Posture

PubMed Central

Cole, Ashley K; McGrath, Melanie L; Harrington, Shana E; Padua, Darin A; Rucinski, Terri J; Prentice, William E

2013-01-01

Context Overhead athletes commonly have poor posture. Commercial braces are used to improve posture and function, but few researchers have examined the effects of shoulder or scapular bracing on posture and scapular muscle activity. Objective To examine whether a scapular stabilization brace acutely alters posture and scapular muscle activity in healthy overhead athletes with forward-head, rounded-shoulder posture (FHRSP). Design Randomized controlled clinical trial. Setting Applied biomechanics laboratory. Patients or Other Participants Thirty-eight healthy overhead athletes with FHRSP. Intervention(s) Participants were assigned randomly to 2 groups: compression shirt with no strap tension (S) and compression shirt with the straps fully tensioned (S + T). Posture was measured using lateral-view photography with retroreflective markers. Electromyography (EMG) of the upper trapezius (UT), middle trapezius (MT), lower trapezius (LT), and serratus anterior (SA) in the dominant upper extremity was measured during 4 exercises (scapular punches, W's, Y's, T's) and 2 glenohumeral motions (forward flexion, shoulder extension). Posture and exercise EMG measurements were taken with and without the brace applied. Main Outcome Measure(s) Head and shoulder angles were measured from lateral-view digital photographs. Normalized surface EMG was used to assess mean muscle activation of the UT, MT, LT, and SA. Results Application of the brace decreased forward shoulder angle in the S + T condition. Brace application also caused a small increase in LT EMG during forward flexion and Y's and a small decrease in UT and MT EMG during shoulder extension. Brace application in the S + T group decreased UT EMG during W's, whereas UT EMG increased during W's in the S group. Conclusions Application of the scapular brace improved shoulder posture and scapular muscle activity, but EMG changes were highly variable. Use of a scapular brace might improve shoulder posture and muscle activity in overhead athletes with poor posture. PMID:23672321

Effects of experimental insoles on body posture, mandibular kinematics and masticatory muscles activity. A pilot study in healthy volunteers.

PubMed

Marini, Ida; Alessandri Bonetti, Giulio; Bortolotti, Francesco; Bartolucci, Maria Lavinia; Gatto, Maria Rosaria; Michelotti, Ambra

2015-06-01

It has been hypothesized that different plantar sensory inputs could influence the whole body posture and dental occlusion but there is a lack of evidence on this possible association. To investigate the effects of experimental insoles redistributing plantar pressure on body posture, mandibular kinematics and electromyographic (EMG) activity of masticatory muscles on healthy subjects. A pilot study was conducted on 19 healthy volunteers that wore custom-made insoles normalizing the plantar pressure distribution for 2 weeks. Body posture parameters were measured by means of an optoelectronic stereophotogrammetric analysis; mandibular kinematics was analyzed by means of gothic arch tracings; superficial EMG activity of head and neck muscles was performed. Measurements were carried out 10 days before the insertion of the insoles, immediately before the insertion, the day after, 7 and 14 days after, in four different exteroceptive conditions. The outcomes of the present study show that insoles do not modify significantly over time the parameters of body posture, SEMG activity of head and neck muscles and mandibular kinematics. In this pilot study the experimental insoles did not significantly influence the body posture, the mandibular kinematics and the activity of masticatory muscles during a 14-day follow up period. Copyright © 2015 Elsevier Ltd. All rights reserved.

Associations of Postural Knowledge and Basic Motor Skill with Dyspraxia in Autism: Implication for Abnormalities in Distributed Connectivity and Motor Learning

PubMed Central

Dowell, Lauren R.; Mahone, E. Mark; Mostofsky, Stewart H.

2009-01-01

Children with autism often have difficulty performing skilled movements. Praxis performance requires basic motor skill, knowledge of representations of the movement (mediated by parietal regions), and transcoding of these representations into movement plans (mediated by premotor circuits). The goals of this study were: (a) to determine whether dyspraxia in autism is associated with impaired representational (“postural”) knowledge, and (b) to examine the contributions of postural knowledge and basic motor skill to dyspraxia in autism. Thirty-seven children with autism spectrum disorder (ASD) and 50 typically developing (TD) children, ages 8–13, completed: (a) an examination of basic motor skills, (b) a postural knowledge test assessing praxis discrimination, and (c) a praxis examination. Children with ASD showed worse basic motor skill and postural knowledge than controls. The ASD group continued to show significantly poorer praxis than controls after accounting for age, IQ, basic motor skill, and postural knowledge. Dyspraxia in autism appears to be associated with impaired formation of spatial representations, as well as transcoding and execution. Distributed abnormality across parietal, premotor, and motor circuitry, as well as anomalous connectivity may be implicated. PMID:19702410

Is there relationship between temporomandibular disorders and head and cervical posture? A systematic review.

PubMed

Rocha, C P; Croci, C S; Caria, P H F

2013-11-01

The objective of this systematic review was to find sufficient evidence to deny or accept the association between the head and cervical posture and temporomandibular disorders (TMDs), and thus assist health professionals in the evaluation and treatment of patients with TMDs. A search was conducted through all publications written in English about this topic using the databases from Medline, ISI Web of Science, EMBASE, PubMed and Lilacs. The abstracts that fulfilled the initial guideline were retrieved and evaluated to ensure they met the inclusion criteria. To assess the methodological quality of the studies, we developed a questionnaire considering the following criteria: participant's eligibility, control group, diagnosis of TMDs, posture diagnosis and randomisation. Twenty-two studies were selected as potential studies based on their abstracts. Only seventeen studies actually fulfilled the inclusion criteria. The search provided information about the methodological quality of the studies, in which several methodological defects were found. The evidence presented in this systematic review shows that the relation between TMDs and the head and neck posture is still controversial and unclear. The insufficient number of articles considered of excellent methodological quality is a factor that hinders the acceptance or denial of this association. © 2013 John Wiley & Sons Ltd.

The effect of over-commitment and reward on trapezius muscle activity and shoulder, head, neck, and torso postures during computer use in the field

PubMed Central

Bruno Garza, Jennifer L.; Eijckelhof, Belinda H.W.; Huysmans, Maaike A.; Catalano, Paul J.; Katz, Jeffrey N.; Johnson, Peter W.; van Dieen, Jaap H.; van der Beek, Allard J.; Dennerlein, Jack T.

2015-01-01

Background Because of reported associations of psychosocial factors and computer related musculoskeletal symptoms, we investigated the effects of a workplace psychosocial factor, reward, in the presence of over-commitment, on trapezius muscle activity and shoulder, head, neck, and torso postures during computer use. Methods We measured 120 office workers across four groups (lowest/highest reward/over-commitment), performing their own computer work at their own workstations over a 2 hour period. Results Median trapezius muscle activity (p=0.04) and median neck flexion (p=0.03) were largest for participants reporting simultaneously low reward and high over-commitment. No differences were observed for other muscle activities or postures. Conclusions These data suggest that the interaction of reward and over-commitment can affect upper extremity muscle activity and postures during computer use in the real work environment. This finding aligns with the hypothesized biomechanical pathway connecting workplace psychosocial factors and musculoskeletal symptoms of the neck and shoulder. PMID:23818000

Sitting on a Sloping Seat Does Not Reduce the Strain Sustained by the Postural Chain

PubMed Central

Hamaoui, Alain; Hassaïne, Myriam; Zanone, Pier-Giorgio

2015-01-01

The objective of this study was to explore the effect of a forward sloping seat on posture and muscular activity of the trunk and lower limbs. To this aim, twelve asymptomatic participants were tested in six conditions varying seat slope (0°, 15° forward) and height (high, medium, low). Angular position of head, trunk and pelvis was assessed with an inertial orientation system, and muscular activity of 11 superficial postural muscles located in the trunk and lower limbs was estimated using normalized EMG. Results showed that a forward sloping seat, compared to a flat seat, induced a greater activity of the soleus (p<0.01), vastus lateralis (p<0.05) and vastus medialis (p<0.05), as well a lower hip flexion (p<0.01). In contrast, no significant variation of head, trunk and pelvis angular position was observed according to seat slope. It was concluded that forward sloping seats increase the load sustained by the lower limbs, without a systematic improvement of body posture. PMID:25587989

DIZZINESS AND HEAD INJURY.

PubMed

BARBER, H O

1965-05-01

Dizziness, whether vague or specifically rotational, is a common sequel to head injury, and is often postural. One hundred and sixty-five patients with this symptom were examined. The simple posture tests employed to detect positional nystagmus are described. This physical finding was present in one-quarter of the entire group, and in nearly one-half of cases of longitudinal fracture of temporal bone. In such cases, it is an objective finding that corresponds precisely to the patient's complaint of vertigo.Transverse fracture of temporal bone destroys the inner ear in both cochlear and vestibular parts. Longitudinal fracture is commoner and causes bleeding from the ear; inner-ear damage is usually minor.In the rare cases where persisting postural vertigo and positional nystagmus are disabling, relief of the symptom may be achieved by vestibular denervation of the affected side.

[Hand and finger anomalous developmental coordination to write in children with attention deficit/hyperactivity syndrome].

PubMed

Pascual-Castroviejo, I; Lobo-Llorente, A

To present a developmental coordination disorder in children with attention deficit/hyperactivity syndrome (ADHS) characterized by anomalous handwriting posture of hands and fingers. Forty-five children who presented with ADHS were studied (39 males and 6 females) with ages ranging from 6 to 16 years (average 10.8 years) and an analysis of the position of the hands and fingers during handwriting was made within the context of a complete neurological evaluation. Only 2 of the 6 hyperactive patients showed a discrete anomalous posture of the fingers, with normality in the other four patients. Seventeen of the 25 children (68%) with ADHS combined type showed poor posture of the fingers when writing. Among the 14 children with ADHS attention deficit type, 8 had abnormal posture when using a pencil, and 4 had shown the problem several years before consulting, and the problem had disappeared after local orthopedic treatment. All 4 left-handed children (3 females and 1 male) presented abnormal posture of the fingers when writing. Evaluation of the anomalous posture of the fingers when writing of patients with ADHS is a test that we commonly use because it is easy to do, the patients collaborate very well to do it and uncovers very early the developmental coordination disorder. The anomalous posture is associated with other coordination disorders and problems of muscular tone such as splay-foot, genu recurvatum, problems with jumping, walking on one foot, etc. in most patients.

Effects of Early Motor Intervention in the Prone Position of Full-Term Infants through the First Year of Life.

ERIC Educational Resources Information Center

Douret, L.

1993-01-01

Full-term infants who had slept in the prone position since birth were followed to detect early postural abnormalities and differentiate potential peripheral abnormality from abnormalities of a central origin. Results showed that disappearance of initial signs of abnormality appeared to be muscular, and symptoms disappeared faster when a motor…

Effect of lower-body positive pressure on postural fluid shifts in men

NASA Technical Reports Server (NTRS)

Hinghofer-Szalkay, H.; Kravik, S. E.; Greenleaf, J. E.

1988-01-01

The effect of the lower-body positive pressure (LBPP) on the orthostatic fluid and protein shifts were investigated in five men during combined tilt-table/antigravity suit inflation and deflation experiments. Changes in the mass densities of venous blood and plasma were measured and the values were used to calculate the densities of erythrocytes, whole-body blood, and shifted fluid. It was found that the application of 60 mm Hg LBPP during 60-deg head-up tilt prevented about half of the postural hemoconcentration occurring during passive head-up tilt.

Vestibulospinal control of reflex and voluntary head movement

NASA Technical Reports Server (NTRS)

Boyle, R.; Peterson, B. W. (Principal Investigator)

2001-01-01

Secondary canal-related vestibulospinal neurons respond to an externally applied movement of the head in the form of a firing rate modulation that encodes the angular velocity of the movement, and reflects in large part the input "head velocity in space" signal carried by the semicircular canal afferents. In addition to the head velocity signal, the vestibulospinal neurons can carry a more processed signal that includes eye position or eye velocity, or both (see Boyle on ref. list). To understand the control signals used by the central vestibular pathways in the generation of reflex head stabilization, such as the vestibulocollic reflex (VCR), and the maintenance of head posture, it is essential to record directly from identified vestibulospinal neurons projecting to the cervical spinal segments in the alert animal. The present report discusses two key features of the primate vestibulospinal system. First, the termination morphology of vestibulospinal axons in the cervical segments of the spinal cord is described to lay the structural basis of vestibulospinal control of head/neck posture and movement. And second, the head movement signal content carried by the same class of secondary vestibulospinal neurons during the actual execution of the VCR and during self-generated, or active, rapid head movements is presented.

Task-specific Dystonias

PubMed Central

Torres-Russotto, Diego; Perlmutter, Joel S.

2009-01-01

Task-specific dystonias are primary focal dystonias characterized by excessive muscle contractions producing abnormal postures during selective motor activities that often involve highly skilled, repetitive movements. Historically these peculiar postures were considered psychogenic but have now been classified as forms of dystonia. Writer’s cramp is the most commonly identified task-specific dystonia and has features typical of this group of disorders. Symptoms may begin with lack of dexterity during performance of a specific motor task with increasingly abnormal posturing of the involved body part as motor activity continues. Initially, the dystonia may manifest only during the performance of the inciting task, but as the condition progresses it may also occur during other activities or even at rest. Neurological exam is usually unremarkable except for the dystonia-related abnormalities. Although the precise pathophysiology remains unclear, increasing evidence suggests reduced inhibition at different levels of the sensorimotor system. Symptomatic treatment options include oral medications, botulinum toxin injections, neurosurgical procedures, and adaptive strategies. Prognosis may vary depending upon body part involved and specific type of task affected. Further research may reveal new insights into the etiology, pathophysiology, natural history, and improved treatment of these conditions. PMID:18990127

Effects of neck and circumoesophageal connective lesions on posture and locomotion in the cockroach.

PubMed

Ridgel, Angela L; Ritzmann, Roy E

2005-06-01

Few studies in arthropods have documented to what extent local control centers in the thorax can support locomotion in absence of inputs from head ganglia. Posture, walking, and leg motor activity was examined in cockroaches with lesions of neck or circumoesophageal connectives. Early in recovery, cockroaches with neck lesions had hyper-extended postures and did not walk. After recovery, posture was less hyper-extended and animals initiated slow leg movements for multiple cycles. Neck lesioned individuals showed an increase in walking after injection of either octopamine or pilocarpine. The phase of leg movement between segments was reduced in neck lesioned cockroaches from that seen in intact animals, while phases in the same segment remained constant. Neither octopamine nor pilocarpine initiated changes in coordination between segments in neck lesioned individuals. Animals with lesions of the circumoesophageal connectives had postures similar to intact individuals but walked in a tripod gait for extended periods of time. Changes in activity of slow tibial extensor and coxal depressor motor neurons and concomitant changes in leg joint angles were present after the lesions. This suggests that thoracic circuits are sufficient to produce leg movements but coordinated walking with normal motor patterns requires descending input from head ganglia.

Cervical vertebral realignment when voluntarily adopting a protective neck posture.

PubMed

Newell, Robyn S; Siegmund, Gunter P; Blouin, Jean-Sébastien; Street, John; Cripton, Peter A

2014-07-01

In vivo human volunteer study of the intervertebral postural changes and muscle activity levels while tensing the neck muscles. To determine if actively tensing the neck muscles changes the posture of the cervical spine and, because axial impact neck injury often occurs while inverted, whether these changes exist both upright and upside down. Rollover accidents are dynamic and complex events in which head contacts with the vehicle interior can cause catastrophic neck injuries. Computational modeling has suggested that active neck muscles may increase the risk of cervical spine fracture in a rollover crash. Cadaver testing has also demonstrated that overall neck alignment and curvature are key to understanding and preventing catastrophic neck injuries. Although muscle activity and neck posture affects the resulting injury, there are currently no in vivo data describing how tensing the neck muscles influences intervertebral posture. Eleven human subjects (6 females, 5 males) actively tensed their neck muscles while seated upright and inverted. Vertebral alignment was measured using fluoroscopy and muscle activity was recorded using surface and indwelling electrodes in 8 neck muscles. On average, tensed muscles increased cervical spine curvature and anterior motion of the cervical vertebrae relative to the torso. These changes, which were magnified by inversion, indicate that cervical intervertebral posture differs considerably between the relaxed and tensed states. Active muscle contraction can change the vertebral alignment in upright and inverted postures. This change in posture may alter the load path and injury mechanics during an axial head impact and may help explain the disparity between the neck injuries observed in real-world rollover accidents and ex vivo cadaver experiments. N/A.

Postural Orthostatic Tachycardia Syndrome during pregnancy: A systematic review of the literature.

PubMed

Morgan, Kate; Chojenta, Catherine; Tavener, Meredith; Smith, Angela; Loxton, Deb

2018-05-09

Postural Orthostatic Tachycardia Syndrome is most commonly seen in women of child bearing age, however little is known about its effects in pregnancy. A systematic review was conducted in March 2015 and updated in February 2018. Medline, Embase, PsychInfo, CINHAL, and the Cochrane Library were searched from database inception. The ClinicalTrials.gov site and bibliographies were searched. MeSH and Emtree headings and keywords included; Postural Orthostatic Tachycardia Syndrome, Postural Tachycardia Syndrome, and were combined with pregnancy and pregnancy related subject headings and keywords. Searches were limited to English. Eligible articles contained key words within the title and or abstract. Articles were excluded if Postural Orthostatic Tachycardia Syndrome was not pre-existing. Eleven articles were identified as eligible for inclusion. Studies were appraised using the PRISMA 2009 guidelines. The overall quality of evidence was poor using the NHMRC Evidence Grading Matrix, which was attributed to small sample sizes and mostly observational studies, emphasizing the need for future high quality research. Findings in this review must be used with caution due to the poor quality of the literature available. Postural Orthostatic Tachycardia Syndrome should not be a contraindication to pregnancy. Symptom course is variable during pregnancy and the post-partum period. Continuing pre-conception medication may help symptoms, with no significant risks reported. Obstetric complications, not Postural Orthostatic Tachycardia Syndrome, should dictate mode of delivery. Postural Orthostatic Tachycardia Syndrome did not appear to affect the rate of adverse events. These results are important in determining appropriate management and care in this population. Copyright © 2018 Elsevier B.V. All rights reserved.

Functional analyses of the primate upper cervical vertebral column.

PubMed

Nalley, Thierra K; Grider-Potter, Neysa

2017-06-01

Recent work has highlighted functional correlations between direct measures of head and neck posture and primate cervical bony morphology. Primates with more horizontal necks exhibit middle and lower cervical vertebral features that indicate increased mechanical advantage for deep nuchal musculature and mechanisms for column curvature formation and maintenance. How features of the C1 and C2 reflect quantified measures of posture have yet to be examined. This study incorporates bony morphology from the upper cervical levels from 20 extant primate species in order to investigate further how posture correlates with cervical vertebrae morphology. Results from phylogenetic generalized least-squares analyses indicate that few vertebral features exhibit a significant relationship with posture when accounting for differences in size. When size-adjusted traits were correlated with posture, vertebral variation had a stronger relationship with neck posture than head posture variables. Two C1 traits-relative posterior arch length and superior facet curvature-were correlated with neck posture variables. Relative posterior arch length exhibits a positive relationship with neck posture, while superior articular facet curvature demonstrates a negative relationship, such that as the neck becomes more horizontal, the greater the facet curvature. Four C2 features were also correlated with neck posture: relative pedicle and lamina lengths, relative superior facet orientation, and dens orientation. Relative pedicle and lamina lengths become craniocaudally longer as the neck becomes more horizontal. Relative C2 superior facet orientation and dens orientation exhibit negative correlations with posture, such that as the neck becomes more horizontal, the superior facet becomes more caudally inclined and the dens more dorsally inclined. These results produce a similar functional signal observed in the middle and lower cervical spine. Modeling the cervical vertebrae of more pronograde taxa within a sigmoidal spinal column model is further discussed and may prove useful in refining and testing future hypotheses of primate cervical mechanics. Copyright © 2017 Elsevier Ltd. All rights reserved.

A method to model anticipatory postural control in driver braking events.

PubMed

Östh, Jonas; Eliasson, Erik; Happee, Riender; Brolin, Karin

2014-09-01

Human body models (HBMs) for vehicle occupant simulations have recently been extended with active muscles and postural control strategies. Feedback control has been used to model occupant responses to autonomous braking interventions. However, driver postural responses during driver initiated braking differ greatly from autonomous braking. In the present study, an anticipatory postural response was hypothesized, modelled in a whole-body HBM with feedback controlled muscles, and validated using existing volunteer data. The anticipatory response was modelled as a time dependent change in the reference value for the feedback controllers, which generates correcting moments to counteract the braking deceleration. The results showed that, in 11 m/s(2) driver braking simulations, including the anticipatory postural response reduced the peak forward displacement of the head by 100mm, of the shoulder by 30 mm, while the peak head flexion rotation was reduced by 18°. The HBM kinematic response was within a one standard deviation corridor of corresponding test data from volunteers performing maximum braking. It was concluded that the hypothesized anticipatory responses can be modelled by changing the reference positions of the individual joint feedback controllers that regulate muscle activation levels. The addition of anticipatory postural control muscle activations appears to explain the difference in occupant kinematics between driver and autonomous braking. This method of modelling postural reactions can be applied to the simulation of other driver voluntary actions, such as emergency avoidance by steering. Copyright © 2014. Published by Elsevier B.V.

Posture variation among office workers when using different information and communication technologies at work and away from work.

PubMed

Ciccarelli, Marina; Straker, Leon; Mathiassen, Svend Erik; Pollock, Clare

2014-01-01

Office workers perform tasks using different information and communication technologies (ICT) involving various postures. Adequate variation in postures and muscle activity is generally believed to protect against musculoskeletal complaints, but insufficient information exists regarding the effect on postural variation of using different ICT. Thus, this study among office workers aimed to determine and compare postures and postural variation associated with using distinct types of ICT. Upper arm, head and trunk postures of 24 office workers were measured with the Physiometer over a whole day in their natural work and away-from-work environments. Postural variation was quantified using two indices: APDF(90-10) and EVA(sd). Various ICT had different postural means and variation. Paper-based tasks had more non-neutral, yet also more variable postures. Electronics-based tasks had more neutral postures, with less postural variability. Tasks simultaneously using paper- and electronics-based ICT had least neutral and least variable postures. Tasks without ICT usually had the most posture variability. Interspersing tasks involving different ICT could increase overall exposure variation among office workers and may thus contribute to musculoskeletal risk reduction.

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

PubMed

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 < .05) and mean arterial 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.

Effectuation of adaptive stability and postural alignment strategies are decreased by alcohol intoxication.

PubMed

Hafström, A; Modig, F; Magnusson, M; Fransson, P A

2014-06-01

Human stability control is a complex process comprising contributions from several partly independent mechanisms such as coordination, feedback and feed-forward control, and adaptation. Acute alcohol intoxication impairs these functions and is recognized as a major contributor to fall traumas. The study aimed to investigate how alcohol intoxication at .06% and .10% blood alcohol concentration (BAC) affected the movement spans and control of posture alignment. The angular positions of the head, shoulder, hip and knees relative to the ankles were measured with a 3D motion analysis system in 25 healthy adults during standing with eyes open or closed and with or without vibratory balance perturbations. Alcohol intoxication significantly increased the movement spans of the head, shoulders, hip and knees in anteroposterior and lateral directions during quiet stance (p < or = .047 and p < or = .003) and balance perturbations (p<.001, both directions). Alcohol intoxication also decreased the ability to reduce the movement spans through adaptation in both anteroposterior (p < or = .011) and lateral (p < or = .004) directions. When sober and submitted to balance perturbations, the subjects aligned the head, shoulders, hip and knees more forward relative to the ankle joint (p < .001), hence adopting a more resilient posture increasing the safety margin for backward falls. Alcohol intoxication significantly delayed this forward realignment (p < or = .022). Alcohol intoxication did not cause any significant posture realignment in the lateral direction. Thus, initiation of adaptive posture realignments to alcohol or other disruptions might be context dependent and associated with reaching a certain level of stability threats. Copyright © 2014 Elsevier B.V. All rights reserved.

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

PubMed

Oh, Hyun-Ju; Song, Gui-Bin

2016-10-01

[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.

Dizziness and Head Injury

PubMed Central

Barber, H. O.

1965-01-01

Dizziness, whether vague or specifically rotational, is a common sequel to head injury, and is often postural. One hundred and sixty-five patients with this symptom were examined. The simple posture tests employed to detect positional nystagmus are described. This physical finding was present in one-quarter of the entire group, and in nearly one-half of cases of longitudinal fracture of temporal bone. In such cases, it is an objective finding that corresponds precisely to the patient's complaint of vertigo. Transverse fracture of temporal bone destroys the inner ear in both cochlear and vestibular parts. Longitudinal fracture is commoner and causes bleeding from the ear; inner-ear damage is usually minor. In the rare cases where persisting postural vertigo and positional nystagmus are disabling, relief of the symptom may be achieved by vestibular denervation of the affected side. PMID:14285289

Analysis of posture and eye movement responses to Coriolis stimulation under 1 G and microgravity conditions.

PubMed

Sekine, Motoki; Takahashi, Masahiro; Iida, Masahiro

2009-12-20

To detect the effect of microgravity on vestibular responses, we conducted Coriolis stimulation experiments at 1 G and μ G. Five men with vision occluded were asked to tilt their head forward while rotating at 100 degrees/sec. Postural changes were recorded by a 3D linear accelerometer, and the distance of upper body movement was derived from recordings of linear acceleration. Eye movements were recorded by a CCD camera. For a second period after commencing head tilt, the upper body moved 10 cm in the direction of inertia input at 1 G, but it moved to the opposite direction at μ G, i.e., 4 cm in the direction of inertia force. Nystagmus peak slow-phase velocity immediately after head tilt and its attenuation process did not differ between 1 G and μ G. The strength of movement sensation and the severity of motion sickness were far weaker at μ G than at 1 G. It was concluded that inertia input is valid to induce postural and sensation responses only when the external reference is given Z axis by gravity. Vestibular ocular response may be maintained at μ G because the head reference is valid even after the external reference becomes arbitrary.

Detection of Cardiopulmonary Activity and Related Abnormal Events Using Microsoft Kinect Sensor.

PubMed

Al-Naji, Ali; Chahl, Javaan

2018-03-20

Monitoring of cardiopulmonary activity is a challenge when attempted under adverse conditions, including different sleeping postures, environmental settings, and an unclear region of interest (ROI). This study proposes an efficient remote imaging system based on a Microsoft Kinect v2 sensor for the observation of cardiopulmonary-signal-and-detection-related abnormal cardiopulmonary events (e.g., tachycardia, bradycardia, tachypnea, bradypnea, and central apnoea) in many possible sleeping postures within varying environmental settings including in total darkness and whether the subject is covered by a blanket or not. The proposed system extracts the signal from the abdominal-thoracic region where cardiopulmonary activity is most pronounced, using a real-time image sequence captured by Kinect v2 sensor. The proposed system shows promising results in any sleep posture, regardless of illumination conditions and unclear ROI even in the presence of a blanket, whilst being reliable, safe, and cost-effective.

Detection of Cardiopulmonary Activity and Related Abnormal Events Using Microsoft Kinect Sensor

PubMed Central

Chahl, Javaan

2018-01-01

Monitoring of cardiopulmonary activity is a challenge when attempted under adverse conditions, including different sleeping postures, environmental settings, and an unclear region of interest (ROI). This study proposes an efficient remote imaging system based on a Microsoft Kinect v2 sensor for the observation of cardiopulmonary-signal-and-detection-related abnormal cardiopulmonary events (e.g., tachycardia, bradycardia, tachypnea, bradypnea, and central apnoea) in many possible sleeping postures within varying environmental settings including in total darkness and whether the subject is covered by a blanket or not. The proposed system extracts the signal from the abdominal-thoracic region where cardiopulmonary activity is most pronounced, using a real-time image sequence captured by Kinect v2 sensor. The proposed system shows promising results in any sleep posture, regardless of illumination conditions and unclear ROI even in the presence of a blanket, whilst being reliable, safe, and cost-effective. PMID:29558414

Head movement measurement: An alternative method for posturography studies.

PubMed

Ciria, L F; Muñoz, M A; Gea, J; Peña, N; Miranda, J G V; Montoya, P; Vila, J

2017-02-01

The present study evaluated the measurement of head movements as a valid method for postural emotional studies using the comparison of simultaneous recording of center of pressure (COP) sway as criterion. Thirty female students viewed a set of 12 pleasant, 12 unpleasant and 12 neutral pictures from the International Affective Picture System, repeated twice, using a block presentation procedure while standing on a force platform (AMTI AccuSway). Head movements were recorded using a webcam (©KPC139E) located in the ceiling in line with the force platform and a light-emitting diode (LED) placed on the top of the head. Open source software (CvMob 3.1) was used to process the data. High indices of correlation and coherence between head and COP sway were observed. In addition, pleasant pictures, compared with unpleasant pictures, elicited greater body sway in the anterior-posterior axis, suggesting an approach response to appetitive stimuli. Thus, the measurement of head movement can be an alternative or complementary method to recording COP for studying human postural changes. Copyright © 2016 Elsevier B.V. All rights reserved.

Neuropathological aspects of conservative treatment of scoliosis. A theoretical view point.

PubMed

Czupryna, Krzysztof; Nowotny-Czupryna, Olga; Nowotny, Janusz

2012-01-01

An upright body posture cannot be maintained passively for reasons including a high location of the centre of gravity (COG) and a small support area. Proper alignment of body parts is maintained automatically, tending towards a pattern encoded in the CNS. A particularly important role in posture regulation is played by the short muscles of the back, which respond to being stretched with a contraction. During the early phase of scoliosis, the CNS automatically corrects abnormalities, but over time habituation occurs and the CNS treats them as something normal. Any attempt to restore proper body alignment is treated as an error and CNS automatically restores this abnormal pattern. With a prolonged deviation in body part alignment, CNS treats it as a defect and runs compensatory mechanisms to restore the balance of the body as a whole. Balance is ensured by postural compensation, but this does not restore proper body part alignment. In the treatment of scoliosis, it is important both to slow down progression and to prevent the development of abnormal postural habits, which are part of a vicious circle even without progression. Secondary prevention is therefore needed in all patients. Passive observation limits the possibilities for prevention and contradicts the principle of early implementation of rehabilitation. Depending on the size of the angle of curvature, recommended treatments of scoliosis comprise observation, corset bracing, and surgery. Physiotherapy is often treated as an unconventional and ineffective treatment. Often, the biggest problem is transferring the resulting correction to automatic maintenance of a correct posture in the vertical position. The aim of this paper was to discuss the conservative treatment of scoliosis with regard to difficulties maintaining the correct alignment of the body parts in the vertical position that accompany scoliosis.

Reducing the risk of falls through proprioceptive dynamic posture training in osteoporotic women with kyphotic posturing: a randomized pilot study.

PubMed

Sinaki, Mehrsheed; Lynn, Susan G

2002-04-01

To assess the effect of a proprioceptive dynamic posture training program on balance in osteoporotic women with kyphotic posture. Subjects were randomly assigned to either a proprioceptive dynamic posture training program or exercise only group. Anthropometric measurements, muscle strength, level of physical activity, computerized dynamic posturography, and spine radiography were performed at baseline and 1 mo. At the 1-mo follow-up, three groups were formed on the basis of the baseline computerized dynamic posturography results. In general, groups 1 and 2 had no significant change at 1 mo, whereas group 3 improved balance significantly at 1 mo. The subjects who had abnormal balance and used the proprioceptive dynamic posture training program had the most significant improvement in balance. Improved balance could reduce the risk of falls.

Augmented superior rectus transposition procedure in Duane retraction syndrome compared with sixth nerve palsy.

PubMed

Akbari, Mohammadreza; Shomali, Setareh; Mirmohammadsadeghi, Arash; Fard, Masoud Aghsaei

2018-05-01

Superior rectus transposition (SRT) with medial rectus recession has been used for the treatment of sixth nerve palsy and esotropic Duane retraction syndrome (DRS). The purpose of this study was to compare the results of augmented SRT (with scleral fixation) without medial rectus recession in DRS and sixth nerve palsy. Patients with unilateral esotropic DRS (DRS group) and sixth nerve palsy were included in this prospective, comparative study and underwent SRT. Preoperative forced duction testing was negative or slightly positive in both groups. Prospective measurements were compared between the two groups. There were 11 patients in the DRS group and 11 patients in the sixth nerve palsy group. The mean preoperative esotropia decreased from 20.9 ± 6.0 prism diopter (PD) at far to 13.2 ± 5.8 PD in the DRS group (P = 0.003). The same measurement improved from 28.0 ± 8.5 PD to 8.4 ± 7.3 PD in the sixth nerve palsy group (P = 0.003). In the sixth nerve palsy group, the improvement in primary gaze esotropia and abnormal head posture was more than the DRS group (Both P < 0.001).The average dose effect for SRT was 7.8 ± 2.2 PD in the DRS group and 19.2 ± 4.6 PD in the sixth nerve palsy group. Although objective intorsion was significantly induced after SRT, subjective torsion was not significant after surgery in both groups. SRT appears to be more effective in improving primary gaze deviation and head posture in sixth nerve palsy compared with DRS. Subjective torsional and vertical diplopia were rare in both groups.

ASB clinical biomechanics award winner 2016: Assessment of gaze stability within 24-48hours post-concussion.

PubMed

Murray, Nicholas G; D'Amico, Nathan R; Powell, Douglas; Mormile, Megan E; Grimes, Katelyn E; Munkasy, Barry A; Gore, Russell K; Reed-Jones, Rebecca J

2017-05-01

Approximately 90% of athletes with concussion experience a certain degree of visual system dysfunction immediately post-concussion. Of these abnormalities, gaze stability deficits are denoted as among the most common. Little research quantitatively explores these variables post-concussion. As such, the purpose of this study was to investigate and compare gaze stability between a control group of healthy non-injured athletes and a group of athletes with concussions 24-48hours post-injury. Ten collegiate NCAA Division I athletes with concussions and ten healthy control collegiate athletes completed two trials of a sport-like antisaccade postural control task, the Wii Fit Soccer Heading Game. During play all participants were instructed to minimize gaze deviations away from a central fixed area. Athletes with concussions were assessed within 24-48 post-concussion while healthy control data were collected during pre-season athletic screening. Raw ocular point of gaze coordinates were tracked with a monocular eye tracking device (240Hz) and motion capture during the postural task to determine the instantaneous gaze coordinates. This data was exported and analyzed using a custom algorithm. Independent t-tests analyzed gaze resultant distance, prosaccade errors, mean vertical velocity, and mean horizontal velocity. Athletes with concussions had significantly greater gaze resultant distance (p=0.006), prosaccade errors (p<0.001), and horizontal velocity (p=0.029) when compared to healthy controls. These data suggest that athletes with concussions had less control of gaze during play of the Wii Fit Soccer Heading Game. This could indicate a gaze stability deficit via potentially reduced cortical inhibition that is present within 24-48hours post-concussion. Copyright © 2017 Elsevier Ltd. All rights reserved.

Postural Tachycardia Syndrome and Vasovagal Syncope: A Hidden Case of Obstructive Cardiomyopathy without Severe Septal Hypertrophy

PubMed Central

Ho, Natalie; Shields, Robert W.; Cremer, Paul; Rodriguez, L. Leonardo

2018-01-01

A 36-year-old female with symptoms of orthostatic intolerance and syncope was diagnosed with vasovagal syncope on a tilt table test and with postural tachycardia syndrome (POTS) after a repeat tilt table test. However, an echocardiogram at our institution revealed obstructive cardiomyopathy without severe septal hypertrophy, with a striking increase in left ventricular outflow tract gradient from 7 mmHg at rest to 75 mmHg during Valsalva, with a septal thickness of only 1.3 cm. Cardiac MRI showed an apically displaced multiheaded posteromedial papillary muscle with suggestion of aberrant chordal attachments to the anterior mitral leaflet contributing to systolic anterior motion of the mitral valve. She underwent surgery with reorientation of the posterior medial papillary muscle head, resection of the tethering secondary chordae to the A1 segment of the mitral valve, chordal shortening and tacking of the chordae to the A1 and A2 segments of the mitral valve, and gentle septal myectomy. After surgery, she had significant improvement in her prior symptoms. To our knowledge, this is the first reported case of obstructive cardiomyopathy without severe septal hypertrophy with abnormalities in papillary muscle and chordal attachment, in a patient diagnosed with vasovagal syncope and POTS. PMID:29850268

Postural Tachycardia Syndrome and Vasovagal Syncope: A Hidden Case of Obstructive Cardiomyopathy without Severe Septal Hypertrophy.

PubMed

Mayuga, Kenneth A; Ho, Natalie; Shields, Robert W; Cremer, Paul; Rodriguez, L Leonardo

2018-01-01

A 36-year-old female with symptoms of orthostatic intolerance and syncope was diagnosed with vasovagal syncope on a tilt table test and with postural tachycardia syndrome (POTS) after a repeat tilt table test. However, an echocardiogram at our institution revealed obstructive cardiomyopathy without severe septal hypertrophy, with a striking increase in left ventricular outflow tract gradient from 7 mmHg at rest to 75 mmHg during Valsalva, with a septal thickness of only 1.3 cm. Cardiac MRI showed an apically displaced multiheaded posteromedial papillary muscle with suggestion of aberrant chordal attachments to the anterior mitral leaflet contributing to systolic anterior motion of the mitral valve. She underwent surgery with reorientation of the posterior medial papillary muscle head, resection of the tethering secondary chordae to the A1 segment of the mitral valve, chordal shortening and tacking of the chordae to the A1 and A2 segments of the mitral valve, and gentle septal myectomy. After surgery, she had significant improvement in her prior symptoms. To our knowledge, this is the first reported case of obstructive cardiomyopathy without severe septal hypertrophy with abnormalities in papillary muscle and chordal attachment, in a patient diagnosed with vasovagal syncope and POTS.

Purkinje cell heterotopy with cerebellar hypoplasia in two free-living American kestrels (Falco sparverius)

USDA-ARS?s Scientific Manuscript database

Two wild fledgling kestrels exhibited lack of motor coordination, postural reaction deficits, and abnormal propioception. At necropsy, the cerebellum and brainstem were markedly underdeveloped. Microscopically, there was Purkinje cells heterotopy, abnormal circuitry, and hypoplasia with defective fo...

Fingertip contact suppresses the destabilizing influence of leg muscle vibration

NASA Technical Reports Server (NTRS)

Lackner, J. R.; Rabin, E.; DiZio, P.

2000-01-01

Touch of the hand with a stationary surface at nonmechanically supportive force levels (<1 N) greatly attenuates postural sway during quiet stance. We predicted such haptic contact would also suppress the postural destabilization caused by vibrating the right peroneus brevis and longus muscles of subjects standing heel-to-toe with eyes closed. In experiment 1, ten subjects were tested under four conditions: no-vibration, no-touch; no-vibration, touch; vibration, no-touch; and vibration, touch. A hand-held physiotherapy vibrator (120 Hz) was applied approximately 5 cm above the malleolous to stimulate the peroneus longus and brevis tendons. Touch conditions involved contact of the right index finger with a laterally positioned surface (<1 N of force) at waist height. Vibration in the absence of finger contact greatly increased the mean sway amplitude of the center of pressure and of the head relative to the no-vibration, no-touch control condition (P < 0.001). The touch, no-vibration and touch-vibration conditions were not significantly different (P > 0.05) from each other and both had significantly less mean sway amplitude of head and of center of pressure than the other conditions (P < 0.01). In experiment 2, eight subjects stood heel-to-toe under touch and no-touch conditions involving 40-s duration trials of peroneus tendon vibration at different duty cycles: 1-, 2-, 3-, and 4-s ON and OFF periods. The vibrator was attached to the subject's leg and remotely activated. In the no-touch conditions, subjects showed periodic postural disruptions contingent on the duty cycle and mirror image rebounds with the offset of vibration. In the touch conditions, subjects were much less disrupted and showed compensations occurring within 500 ms of vibration onset and mirror image rebounds with vibration offset. Subjects were able to suppress almost completely the destabilizing influence of the vibration in the 3- and 4-s duty cycle trials. These experiments show that haptic contact of the hand with a stable surface can suppress abnormal proprioceptive and motor signals in leg muscles.

Classification of Posture in Poststroke Upper Limb Spasticity: A Potential Decision Tool for Botulinum Toxin A Treatment?

ERIC Educational Resources Information Center

Hefter, Harald; Jost, Wolfgang H.; Reissig, Andrea; Zakine, Benjamin; Bakheit, Abdel Magid; Wissel, Jorg

2012-01-01

A significant percentage of patients suffering from a stroke involving motor-relevant central nervous system regions will develop a spastic movement disorder. Hyperactivity of different muscle combinations forces the limbs affected into abnormal postures or movement patterns. As muscular hyperactivity can effectively and safely be treated with…

Human Energy Expenditure and Postural Coordination on the Mechanical Horse.

PubMed

Baillet, Héloïse; Thouvarecq, Régis; Vérin, Eric; Tourny, Claire; Benguigui, Nicolas; Komar, John; Leroy, David

2017-01-01

The authors investigated and compared the energy expenditure and postural coordination of two groups of healthy subjects on a mechanical horse at 4 increasing oscillation frequencies. Energy expenditure was assessed from the oxygen consumption, respiratory quotient, and heart rate values, and postural coordination was characterized by relative phase computations between subjects (elbow, head, trunk) and horse. The results showed that the postural coordination of the riders was better adapted (i.e., maintenance of in-phase and antiphase) than that of the nonriders, but the energy expenditure remains the same. Likewise, we observed an energy system shifting only for nonriders (from aerobic to lactic anaerobic mode). Finally, cross-correlations showed a link between energy expenditure and postural coordination in the riders (i.e., effectiveness).

Chiropractic biophysics technique: a linear algebra approach to posture in chiropractic.

PubMed

Harrison, D D; Janik, T J; Harrison, G R; Troyanovich, S; Harrison, D E; Harrison, S O

1996-10-01

This paper discusses linear algebra as applied to human posture in chiropractic, specifically chiropractic biophysics technique (CBP). Rotations, reflections and translations are geometric functions studied in vector spaces in linear algebra. These mathematical functions are termed rigid body transformations and are applied to segmental spinal movement in the literature. Review of the literature indicates that these linear algebra concepts have been used to describe vertebral motion. However, these rigid body movers are presented here as applying to the global postural movements of the head, thoracic cage and pelvis. The unique inverse functions of rotations, reflections and translations provide a theoretical basis for making postural corrections in neutral static resting posture. Chiropractic biophysics technique (CBP) uses these concepts in examination procedures, manual spinal manipulation, instrument assisted spinal manipulation, postural exercises, extension traction and clinical outcome measures.

Influence of Near Tasks on Posture in Myopic Chinese Schoolchildren

PubMed Central

Bao, Jinhua; Drobe, Björn; Wang, Yuwen; Chen, Ke; Seow, Eu Jin; Lu, Fan

2015-01-01

ABSTRACT Purpose To investigate near-vision posture in Chinese myopic schoolchildren and compare near-vision posture during different near-vision tasks (i.e., playing video games, reading, and writing). Methods The study investigated 120 myopic children (grades 1 through 6 and aged 6 to 13 years). An electromagnetic motion-tracking system was used for continuous measurements of the working distance and head declination of the subjects while they were playing video games or reading or writing at a desk. The reading and writing documents were adjusted by grade level (i.e., grades 1 to 2, 3 to 4, and 5 to 6). For analysis, the subjects were grouped in two refractive groups according to their median spherical equivalent refractive error (−1.50D). Results The myopic schoolchildren used close working distances for all tasks: 21.3 ± 5.2 cm (video games), 27.2 ± 6.4 cm (reading), and 24.9 ± 5.8 cm (writing). The mean head declinations were 63.5 ± 12.2 deg (video games), 37.1 ± 12.8 deg (reading), and 44.5 ± 14.1 deg (writing). Working distance decreased significantly across time for the reading and writing tasks (p < 0.001). Head declination increased significantly across time only for the reading task (p < 0.001). Grade level significantly influenced working distance, but the difference was not significant when working distance was adjusted by the subject’s size. No differences were observed within the refractive or the accommodative lag groups in terms of the posture data (p > 0.05). Working distance was negatively correlated with head declination (r = −0.53, p < 0.001). Conclusions Close working distances were observed for Chinese myopic schoolchildren. The attention dedicated to each task, the task difficulty, and the page/screen size may affect near working distance and head declination. Handheld video games were associated with the closest working distance, which may be a risk factor for myopia progression, according to previous studies. PMID:26107025

Effect of posture on arterial baroreflex control of heart rate in humans

NASA Technical Reports Server (NTRS)

Harrison, M. H.; Rittenhouse, D.; Greenleaf, J. E.

1986-01-01

The effects of blood-volume redistribution induced by postural changes on baroreflex activity are investigated. The central blood volume and baroreceptor functions of ten males between 23-51 years old were examined while they were in the head-up tilt (HUT), head-down tilt (HDT), and supine positions. It is observed that during HDT at 15 deg the pulse interval over the first five cardiac cycles following neck suction onset is 51 + or - 18 ms longer, at 30 deg it is 61 + or - 20 ms longer, and at 45 deg it is 74 + or - 35 ms longer than at supine; during HUT at 15 deg the pulse interval is 25 + or - 9 ms shorter than when supine, but for the 30 and 45 deg there is no significant difference in pulse interval detected. The data reveal that posture does modify arterial baroreflex control of heart rate.

Head and cervical posture in patients with temporomandibular disorders.

PubMed

Armijo-Olivo, Susan; Rappoport, Karen; Fuentes, Jorge; Gadotti, Inae Caroline; Major, Paul W; Warren, Sharon; Thie, Norman M R; Magee, David J

2011-01-01

To determine whether patients with myogenous or mixed (ie, myogeneous plus arthrogeneous) temporomandibular disorders (TMD) had different head and cervical posture measured through angles commonly used in clinical research settings when compared to healthy individuals. One hundred fifty-four persons participated in this study. Of these, 50 subjects were healthy, 55 subjects had myogenous TMD, and 49 subjects had mixed TMD (ie, arthrogenous plus myogenous TMD). A lateral photograph was taken with the head in the self-balanced position. Four angles were measured in the photographs: (1) Eye-Tragus-Horizontal, (2) Tragus-C7-Horizontal, (3) Pogonion-Tragus-C7, and (4) Tragus-C7-Shoulder. Alcimagen software specially designed to measure angles was used in this study. All of the measurements were performed by a single trained rater, a dental specialist in orthodontics, blinded to each subject's group status. The only angle that reached statistical significance among groups was the Eye-Tragus-Horizontal (F = 3.03, P = .040). Pairwise comparisons determined that a mean difference of 3.3 degrees (95% confidence intervals [CI]: 0.15, 6.41) existed when comparing subjects with myogenous TMD and healthy subjects (P = .036). Postural angles were not significantly related to neck disability, jaw disability, or pain intensity. Intrarater and interrater reliability of the measurements were excellent, with intraclass correlation coefficient (ICC) values ranging between 0.996-0.998. The only statistically significant difference in craniocervical posture between patients with myogenous TMD and healthy subjects was for the Eye-Tragus-Horizontal angle, indicating a more extended position of the head. However, the difference was very small (3.3 degrees) and was judged not to be clinically significant.

Journal Club: Head CT scans in the emergency department for syncope and dizziness.

PubMed

Mitsunaga, Myles M; Yoon, Hyo-Chun

2015-01-01

The purpose of this study was to determine the yield of acutely abnormal findings on head CT scans in patients presenting to the emergency department with dizziness, near-syncope, or syncope and to determine the clinical factors that potentially predicted acutely abnormal head CT findings and hospital admission. We retrospectively reviewed the electronic medical records of all patients presenting to an HMO emergency department between July 1, 2012, and December 31, 2012, who underwent head CT for a primary complaint of dizziness, syncope, or near-syncope. The primary outcomes were head CT scans with acutely abnormal findings and hospital admission. Binary logistic regression was used to assess the association between clinical variables and acute head CT findings and between clinical variables and hospital admission. Of the 253 patients who presented with dizziness, 7.1% had head CT scans with acutely abnormal findings, and 18.6% were admitted. Of the 236 patients who presented with syncope or near-syncope, 6.4% had head CT scans with acutely abnormal findings, and 39.8% were admitted. The following three clinical factors were found to be significantly correlated with acutely abnormal head CT findings: a focal neurologic deficit (p = 0.003), age greater than 60 years (p = 0.011), and acute head trauma (p = 0.026). Our results suggest that most patients presenting with syncope or dizziness to the emergency department may not benefit from head CT unless they are older, have a focal neurologic deficit, or have a history of recent head trauma.

Evaluation of work posture and quantification of fatigue by Rapid Entire Body Assessment (REBA)

NASA Astrophysics Data System (ADS)

Rizkya, I.; Syahputri, K.; Sari, R. M.; Anizar; Siregar, I.

2018-02-01

Work related musculoskeletal disorders (MSDs), poor body postures, and low back injuries are the most common problems occurring in many industries including small-medium industries. This study presents assessment and evaluation of ergonomic postures of material handling worker. That evaluation was carried out using REBA (Rapid Entire Body Assessment). REBA is a technique to quantize the fatigue experienced by the worker while manually lifting loads. Fatigue due to abnormal work posture leads to complaints of labor-perceived pain. REBA methods were used to an assessment of working postures for the existing process by a procedural analysis of body postures involved. This study shows that parts of the body have a high risk of work are the back, neck, and upper arms with REBA score 9, so action should be taken as soon as possible. Controlling actions were implemented to those process with high risk then substantial risk reduction was achieved.

Universal Head Ultrasound Screening in Full-term Neonates: A Retrospective Analysis of 6771 Infants.

PubMed

Ballardini, Elisa; Tarocco, Anna; Rosignoli, Chiara; Baldan, Alessandro; Borgna-Pignatti, Caterina; Garani, Giampaolo

2017-06-01

Full-term neonates may have asymptomatic cranial injuries at birth and head ultrasound screening could be useful for early diagnosis. The aim of this study was to assess the prevalence and type of intracranial abnormalities and the usefulness of head ultrasound screening in these infants. Head ultrasound screening was performed on all full-term neonates (gestational age between 37 and 42 weeks), born at Sant'Anna University Hospital of Ferrara, Italy, from June 1, 2008 through May 31, 2013. Ultrasound findings were categorized into three groups: normal, minor, and major anomalies. All full-term neonates (6771) born at our hospital underwent head ultrasound screening. One hundred fourteen of 6771 (1.7%) presented ultrasound abnormalities, whereas 6657 were normal or exhibited insignificant findings. In 101 of 114 (88.6%), abnormalities were minor, and only 13 infants had major abnormalities (0.19% of all full-term newborns). All neonates with major abnormalities presented with either microcephaly or abnormal neurological evaluations. Only one individual with major abnormalities was detected exclusively by ultrasound. The number of significant anomalies detected by head ultrasound screening in asymptomatic full-term neonates born during the study period was low. Therefore, there is no indication for routine general head ultrasound screening in these patients. However, even if low, in neonates who have neurological abnormalities, risk factors or suspected brain malformations, head ultrasound screening may play an important role in the early diagnosis of intracranial anomalies. Copyright © 2017 Elsevier Inc. All rights reserved.

Orientation and position of head posture, scapula and thoracic spine in mouth-breathing children.

PubMed

Neiva, Patrícia Dayrell; Kirkwood, Renata Noce; Godinho, Ricardo

2009-02-01

Mouth-breathing is a common clinical condition among school-age children and some studies have correlated this condition with quality of life and postural alterations. Therefore, the objective of this study was to investigate the orientation and position of the scapula, thoracic spine and head posture among mouth-breathing (MB) children and nasal-breathing (NB) children. Twenty-one male MB children and 21 male NB children between 8 and 12 years of age participated in the study. Data were obtained through a stereophotogrammetry system that uses passive markers over anatomical landmarks to capture the position of the segments. Internal rotation, upward rotation, anterior tilt, scapular elevation and abduction were measured bilaterally as well as thoracic kyphosis, forward head position and shoulder protrusion. The MB children showed increased scapular superior position in relation to the NB group. No statistically significant differences were found between groups regarding the angular and linear measurements of the scapula. To verify reliability, three measurements were taken for each variable in the study. The intraclass correlation coefficient (ICC) showed results above 0.8 for all the variables except for the internal rotation angle (I-Rot), below 0.5, probably due to uncertainty in the palpation of the inferior angle of the scapula. Ninety-five percent of the NB children and 58% among the MB children had been breastfed, this difference was statistically significant. There were statistically significant differences between groups regarding the domains of the Autoquestionnaire Qualité de Vie Enfant Imagé (AUQEI) scale and body mass index, which was higher among the NB children. MB children increased scapular superior position in comparison to NB children due probably to the position of forward head, leading to an alteration in the positioning of the mandible. The absence of significantly difference in posture pattern between groups in the present study could attributed to height-weight development in this age, as the posture of children changes in order to adapt to new body proportions, regardless of health status. The results observed in this study demonstrate the importance of using reliable measurements in the postural assessment of MB and NB children helping physical therapists to focus their strategies during rehabilitation in more specific conditions.

Mechanism of Headward Fluid Shift During Exposure To Microgravity

NASA Technical Reports Server (NTRS)

Hargens, Alan R.; Parazynski, Scott E.; Watenpaugh, Donald E.; Aratow, Michael; Murthy, Gita; Kawai, Yasuaki

1994-01-01

A prominent feature of early cardiovascular adaptation to the microgravity of space flight is a shift of blood and tissue fluid from the lower body to the upper body. Symptoms of this fluid shift include facial edema, nasal congestion, and headache. Normally on Earth, the human body is exposed to hydrostatic (gravitational) blood pressure gradients during upright posture. In this posture, mean arterial pressures at head, heart, and foot levels are approximately 70, 100, and 200 mm Hg, respectively. Theoretically, all hydrostatic pressures within arteries and veins are lost during exposure to microgravity so that mean arterial pressure in all regions of the body is uniform and approximately equal to that at heart level (100 mm Hg). Acute studies of 60 head-down tilt (simulated microgravity on Earth) indicate that facial edema is caused by: 1) elevation of capillary blood pressure from 28 to 34 mm Hg, 2) reduction of blood colloid osmotic pressure 22 to 18 mm Hg, and 3) 50% increase of blood perfusion in tissues of the head. Furthermore, as compared to microvasculature in the feet, microvessels of the head have a low capacity to constrict and diminish local perfusion. Elevation of blood and tissue fluid pressures/flow in the head may also explain the higher headward bone density associated with long-term head-down tilt. These mechanistic studies of head-down tilt, along with a better understanding of the relative stresses involved with upright posture and lower body negative pressure, have facilitated development of physiologic countermeasures to maintain astronaut health during microgravity. Presently no exercise hardware is available to provide a blood pressure gradient from head to feet in space. However, recent studies in our laboratory suggest that treadmill exercise within lower body negative pressure provides equivalent or greater physiologic stress as compared to similar upright exercise on Earth.

Modified Y-splitting Procedure for the Treatment of Duane Retraction Syndrome.

PubMed

Altıntaş, Ayşe Gül; Arifoğlu, Hasan Basri; Köklü, Şükrü Gültekin

2015-08-01

To present the outcomes of modified lateral rectus Y-splitting combined with either unilateral or bilateral horizontal rectus recession in Duane Retraction Syndrome (DRS) with significant upshoot or downshoot. A total of 12 patients including 10 patients with Type I DRS and 2 with Type III DRS underwent modified Y-splitting surgery. Amount of additional recessions varied with the degree of preoperative deviation by intraoperative adjustable suture technique. Preoperatively 3 patients had esotropia (ET), 6 had exotropia (XT), and 3 patients had orthotropia. The mean preoperative deviation was 19.3 prism diopters (PD) (range, 18-20 PD) in ET patients and 19.2 PD (range, 16-20 PD) in XT patients. Postoperatively, all patients had significant correction in horizontal deviation and aligned within 4 PD of orthotropia, and no patients exhibited abnormal head posture. Co-contraction and globe retraction were markedly reduced and abnormal ocular vertical movement disappeared or significantly decreased in all cases. No patients experienced recurrence of ocular motility disorders in the mean 26-month (range, 13-66 months) follow-up period. Modified Y-splitting surgery combined with co-contracting horizontal muscle recession technique seems to be a safe and effective treatment in DRS.

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

PubMed Central

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

Comparison of isometric cervical flexor and isometric cervical extensor system exercises on patients with neuromuscular imbalance and cervical crossed syndrome associated forward head posture.

PubMed

Lee, Jaejin; Kim, Dohyeon; Yu, Kyunghoon; Cho, Youngki; You, Joshua H

2018-01-01

Isometric cervical flexor system exercise (ICF) and isometric cervical extensor system exercise (ICE) are cervical stabilization techniques that have been used to restore cervical crossed syndrome (CCS)-associated forward head posture. However, the therapeutic effects and underlying motor control mechanisms remain elusive. The purpose of present study was investigating the concurrent therapeutic effects of ICF and ICE on muscle size, muscle imbalance ratio, and muscle recruitment sequence using ultrasound imaging and electromyography. A total of 18 participants (7 females; age=24±4.0 years) with CCS associated with forward head posture underwent ICF and ICE. Paired t-test analysis was used for statistical analysis. Paired t-test analysis showed that sternocleidomastoid thickness was greater during ICF than ICE. Similarly, cross-sectional area and horizontal thickness of the longus colli were greater during ICE than ICF. The upper trapezius/lower trapezius muscle imbalance ratio and the pectoralis major/lower trapezius muscle imbalance ratio were significantly decreased during the application of ICE compared to ICF. These results provide compelling, mechanistic evidence as to how ICE is more beneficial for the restoration of neuromuscular imbalance than ICF in individuals with CCS.

Ocular manifestations of gravity inversion.

PubMed

Friberg, T R; Weinreb, R N

To determine the ocular manifestations of inverting the human body into a head-down vertical position, we evaluated normal volunteers with applanation tonometry, fundus photography, fluorescein angiography, and ophthalmodynamometry. Compared with data obtained in the sitting position, the intraocular pressure more than doubled on inversion (35.6 +/- 4 v 14.1 +/- 2.8 mm Hg, n = 16), increasing to levels well within the glaucomatous range. Pressures in the central retinal artery underwent similar increases, while the caliber of the retinal arterioles decreased substantially. External ocular findings associated with gravity inversion included orbital congestion, conjunctival hyperemia, petechiae of the eyelids, excessive tearing (epiphora), and subconjunctival hemorrhage. We suggest that patients with retinal vascular abnormalities, macular degeneration, ocular hypertension, glaucoma, and similar disorders refrain from inversion altogether. Whether normal individuals will suffer irreversible damage from inversion is uncertain, but it seems prudent to recommend that prolonged periods of inverted posturing be avoided.

Head posture and dental wear evaluation of bruxist children with primary teeth.

PubMed

Vélez, A L; Restrepo, C C; Peláez-Vargas, A; Gallego, G J; Alvarez, E; Tamayo, V; Tamayo, M

2007-09-01

The aim of the present study was to compare the head position and dental wear of bruxist and non-bruxist children with primary dentition. All the subjects had complete primary dentition, dental and skeletal class I occlusion and were classified as bruxist or non-bruxist according to their anxiety level, bruxism described by their parents and signs of temporomandibular disorders. The dental wear was drawn in dental casts and processed in digital format. Physiotherapeutic evaluation and a cephalometric radiograph with natural head position were also performed for each child to evaluate the cranio-cervical position for the bruxist group (n = 33) and the control group (n = 20). The variables of the two groups were compared, using the Student t-test and Mann-Whitney U-test. A more anterior and downward head tilt was found in the bruxist group, with statistically significant differences compared with the controls. More significant dental wear was observed in the bruxist children. Bruxism seems to be related to altered natural head posture and more intense dental wear. Further studies are necessary to explore bruxism mechanisms.

Evaluation of body posture in individuals with internal temporomandibular joint derangement.

PubMed

Munhoz, Wagner Cesar; Marques, Amélia Pasqual; de Siqueira, José Tadeu Tesseroli

2005-10-01

Temporomandibular dysfunctions (TMD) comprise a great number of disruptions that may affect the temporomandibular joint (TMJ), the masticatory muscles, or both. TMJ internal derangement is a specific type of TMD, of which the etiology and physiopathology are broadly unknown, but have been suggested to be linked to head, neck, and body posture factors. This study aimed at verifying possible relationships between body posture and TMJ internal derangements (TMJ-id), by comparing 30 subjects presenting typical TMJ-id signs to 20 healthy subjects. Subjects' clinical evaluations included anamnesis, stomatognatic system evaluation, and plotting analysis on body posture photographs. No statistically significant differences were found between the groups. Results do not support the assertion that body posture plays a role in causing or enhancing TMD; however, these results should be cautiously considered because of the small number of subjects evaluated and the many posture variables submitted to statistical procedures that lead to high standard deviations.

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?

PubMed

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.

Usefulness of posture training for patients with temporomandibular disorders.

PubMed

Wright, E F; Domenech, M A; Fischer, J R

2000-02-01

Many practitioners have found that posture training has a positive impact on temporomandibular, or TMD, symptoms. The authors conducted a study to evaluate its effectiveness. Sixty patients with TMD and a primary muscle disorder were randomized into two groups: one group received posture training and TMD self-management instructions while the control group received TMD self-management instructions only. Four weeks after the study began, the authors reexamined the subjects for changes in symptoms, pain-free opening and pressure algometer pain thresholds. In addition, pretreatment and posttreatment posture measurements were recorded for subjects in the treatment group. Statistically significant improvement was demonstrated by the modified symptom severity index, maximum pain-free opening and pressure algometer threshold measurements, as well as by the subjects' perceived TMD and neck symptoms. Subjects in the treatment group reported having experienced a mean reduction in TMD and neck symptoms of 41.9 and 38.2 percent, respectively, while subjects in the control group reported a mean reduction in these symptoms of 8.1 and 9.3 percent. Within the treatment group, the authors found significant correlations between improvements in TMD symptoms and improvements in neck symptoms (P < .005) as well as between TMD symptom improvement and the difference between head and shoulder posture measurements at the outset of treatment (P < .05). Posture training and TMD self-management instructions are significantly more effective than TMD self-management instructions alone for patients with TMD who have a primary muscle disorder. Patients with TMD who hold their heads farther forward relative to the shoulders have a high probability of experiencing symptom improvement as a result of posture training and being provided with selfmanagement instructions.

Cybersickness without the wobble: Experimental results speak against postural instability theory.

PubMed

Dennison, Mark Stephen; D'Zmura, Michael

2017-01-01

It has been suggested that postural instability is necessary for cybersickness to occur. Seated and standing subjects used a head-mounted display to view a virtual tunnel that rotated about their line of sight. We found that the offset direction of perceived vertical settings matched the direction of the tunnel's rotation, so replicating earlier findings. Increasing rotation speed caused cybersickness to increase, but had no significant impact on perceived vertical settings. Postural sway during rotation was similar to postural sway during rest. While a minority of subjects exhibited postural sway in response to the onset of tunnel rotation, the majority did not. Furthermore, cybersickness increased with rotation speed similarly for the seated and standing conditions. Finally, subjects with greater levels of cybersickness exhibited less variation in postural sway. These results lead us to conclude that the link between postural instability and cybersickness is a weak one in the present experiment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Differences in standing and sitting postures of youth with idiopathic scoliosis from quantitative analysis of digital photographs.

PubMed

Fortin, Carole; Ehrmann Feldman, Debbie; Cheriet, Farida; Labelle, Hubert

2013-08-01

The objective of this study was to explore whether differences in standing and sitting postures of youth with idiopathic scoliosis could be detected from quantitative analysis of digital photographs. Standing and sitting postures of 50 participants aged 10-20-years-old with idiopathic scoliosis (Cobb angle: 15° to 60°) were assessed from digital photographs using a posture evaluation software program. Based on the XY coordinates of markers, 13 angular and linear posture indices were calculated in both positions. Paired t-tests were used to compare values of standing and sitting posture indices. Significant differences between standing and sitting positions (p < 0.05) were found for head protraction, shoulder elevation, scapula asymmetry, trunk list, scoliosis angle, waist angles, and frontal and sagittal plane pelvic tilt. Quantitative analysis of digital photographs is a clinically feasible method to measure standing and sitting postures among youth with scoliosis and to assist in decisions on therapeutic interventions.

Advanced Techniques for Assessment of Postural and Locomotor Ataxia, Spatial Orientation, and Gaze Stability

NASA Technical Reports Server (NTRS)

Wall, Conrad., III

1999-01-01

In addition to adapting to microgravity, major neurovestibular problems of space flight include postflight difficulties with standing, walking, turning corners, and other activities that require stable upright posture and gaze stability. These difficulties inhibit astronauts' ability to stand or escape from their vehicle during emergencies. The long-ter7n goal of the NSBRI is the development of countermeasures to ameliorate the effects of long duration space flight. These countermeasures must be tested with valid and reliable tools. This project aims to develop quantitative, parametric approaches for assessing gaze stability and spatial orientation during normal gait and when gait is perturbed. Two of this year's most important findings concern head fixation distance and ideal trajectory analysis. During a normal cycle of walking the head moves up and down linearly. A simultaneous angular pitching motion of the head keeps it aligned toward an imaginary point in space at a distance of about one meter in front of a subject and along the line of march. This distance is called the head fixation distance. Head fixation distance provides the fundamental framework necessary for understanding the functional significance of the vestibular reflexes that couple head motion to eye motion. This framework facilitates the intelligent design of counter-measures for the effects of exposure to microgravity upon the vestibular ocular reflexes. Ideal trajectory analysis is a simple candidate countermeasure based upon quantifying body sway during repeated up and down stair stepping. It provides one number that estimates the body sway deviation from an ideal sinusoidal body sway trajectory normalized on the subject's height. This concept has been developed with NSBRI funding in less than one year. These findings are explained in more detail below. Compared to assessments of the vestibuo-ocular reflex, analysis of vestibular effects on locomotor function is relatively less well developed and quantified. We are improving this situation by applying methodologies such as nonlinear orbital stability to quantify responses and by using multivariate statistical approaches to link together the responses across separate tests. In this way we can exploit the information available and increase the ability to discriminate between normal and pathological responses. Measures of stability and orientation are compared to measures such as dynamic visual acuity and with balance function tests. The responses of normal human subjects and of patients having well documented pathophysiologies are being characterized. When these studies are completed, we should have a clearer idea about normal and abnormal patterns of eye, head, and body movements during locomotion and their stability in a wide range of environments. We plan eventually to use this information to validate the efficacy of candidate neurovestibular and neuromuscular rehabilitative techniques. Some representative studies made during this year are summarized.

Head Stability and Head-Trunk Coordination in Horseback Riders: The Contribution of Visual Information According to Expertise

PubMed Central

Olivier, Agnès; Faugloire, Elise; Lejeune, Laure; Biau, Sophie; Isableu, Brice

2017-01-01

Maintaining equilibrium while riding a horse is a challenging task that involves complex sensorimotor processes. We evaluated the relative contribution of visual information (static or dynamic) to horseback riders' postural stability (measured from the variability of segment position in space) and the coordination modes they adopted to regulate balance according to their level of expertise. Riders' perceptual typologies and their possible relation to postural stability were also assessed. Our main assumption was that the contribution of visual information to postural control would be reduced among expert riders in favor of vestibular and somesthetic reliance. Twelve Professional riders and 13 Club riders rode an equestrian simulator at a gallop under four visual conditions: (1) with the projection of a simulated scene reproducing what a rider sees in the real context of a ride in an outdoor arena, (2) under stroboscopic illumination, preventing access to dynamic visual cues, (3) in normal lighting but without the projected scene (i.e., without the visual consequences of displacement) and (4) with no visual cues. The variability of the position of the head, upper trunk and lower trunk was measured along the anteroposterior (AP), mediolateral (ML), and vertical (V) axes. We computed discrete relative phase to assess the coordination between pairs of segments in the anteroposterior axis. Visual field dependence-independence was evaluated using the Rod and Frame Test (RFT). The results showed that the Professional riders exhibited greater overall postural stability than the Club riders, revealed mainly in the AP axis. In particular, head variability was lower in the Professional riders than in the Club riders in visually altered conditions, suggesting a greater ability to use vestibular and somesthetic information according to task constraints with expertise. In accordance with this result, RFT perceptual scores revealed that the Professional riders were less dependent on the visual field than were the Club riders. Finally, the Professional riders exhibited specific coordination modes that, unlike the Club riders, departed from pure in-phase and anti-phase patterns and depended on visual conditions. The present findings provide evidence of major differences in the sensorimotor processes contributing to postural control with expertise in horseback riding. PMID:28194100

Stimulus Control, Transfer and Maintenance of Upright Walking Posture with a Severely Retarded Adult.

ERIC Educational Resources Information Center

Horner, Robert H.

Upright walking posture was successfully trained, maintained, and transferred to a new setting in a 28-year-old profoundly retarded adult. An apparatus in the S's cap and vest provided reinforcement (radio) when the S's head was up. The first four phases of the study demonstrated stimulus control in the training setting, while the next nine phases…

Furniture dimensions and postural overload for schoolchildren's head, upper back and upper limbs.

PubMed

Batistão, Mariana Vieira; Sentanin, Anna Cláudia; Moriguchi, Cristiane Shinohara; Hansson, Gert-Åke; Coury, Helenice Jane Cote Gil; de Oliveira Sato, Tatiana

2012-01-01

The aim of this study was to evaluate how the fixed furniture dimensions match with students' anthropometry and to describe head, upper back and upper limbs postures and movements. Evaluation was performed in 48 students from a Brazilian state school. Furniture dimensions were measured with metric tape, movements and postures by inclinometers (Logger Tecknologi, Åkarp, Sweden). Seat height was high for 21% and low for 36% of the students; seat length was short for 45% and long for 9% and table height was high for 53% and low for 28%. Regression analysis showed that seat/popliteal height quotient is explained by 90th percentile of upper back inclination (β=0.410) and 90th percentile of right upper arm elevation (β=-0.293). For seat/thigh length quotient the significant variables were 90th percentile of upper back velocity (β=-0.282) and 90th percentile of right upper arm elevation (β=0.410). This study showed a relationship between furniture mismatch and postural overload. When the seat height is low students increase upper back left inclination and right upper arm elevation; when the seat is short students decrease the upper back flexion velocity and increase right upper arm elevation.

Clinical effects of deep cervical flexor muscle activation in patients with chronic neck pain

PubMed Central

Kim, Jin Young; Kwag, Kwang Il

2016-01-01

[Purpose] The purpose of this study was to investigate clinical effects of deep cervical flexor (DCF) muscles exercise on pain, Neck Disability Index (NDI), and neck and shoulder postures in patients with chronic neck pain. [Subjects and Methods] Twenty-eight patients with chronic neck pain were randomly assigned into either the general strengthening exercise (GSE) group or the DCF activation group as control and experimental groups, respectively. All exercises were performed three times per week over 4 weeks. NDI and numeric rating scale (NRS) score for pain were determined and radiological assessment of neck-shoulder postures (head tilt angle [HTA], neck flexion angle [NFA], and forward shoulder angle [FSA]) was performed before (baseline), 4 weeks after, and 8 weeks after exercise in order to directly compare the exercise effects between the groups. [Results] In the DCF group, the NDI, NRS score, and neck-shoulder postures (analyzed by uisng HTA, NFA, and FSA) were significantly improved. [Conclusion] DCF activation exercise was effective to alleviate pain, recover functions, and correct forward head posture in the patients with neck pain. Hence, it might be recommended in the rehabilitation of patients with chronic neck pain. PMID:26957772

INCIDENCE OF POSTURAL CHANGES AND TEMPOROMANDIBULAR DISORDERS IN STUDENTS

PubMed Central

Chaves, Paulo de Jesus; de Oliveira, Franceane Esther Moreira; Damázio, Laila Cristina Moreira

2017-01-01

ABSTRACT Objective: The aim of this study was to identify the incidence of postural changes and temporomandibular disorders (TMD) in children and adolescents . Methods: We selected 117 individuals aged 10-18 years from a state school in the Zona da Mata region of Minas Gerais. The students were evaluated in four stages: assessment of body weight and height and calculation of body mass index; posture evaluation using a questionnaire developed by the researchers; application of a questionnaire recommended by the American Academy of Orofacial Pain to assess TMD; and, finally, application of the Fonseca anamnesis questionnaire . Results: Of our sample, 26.36% had no TMD, 50.9% had mild TMD, 21.8% moderate TMD, and 0.9% severe TMD. Of the participants with moderate or severe TMD (30.8%), about 56% had some kind of change in head positioning. We found that 88% of the children with moderate or severe TMD had changes in the shoulders . Conclusion: The postural changes found in the head and shoulders are related to the biomechanical adaptation of the muscles of mastication and consequent changes in the TMJ. Level Of Evidence Iii, Non-Consecutive Patient Study Without Gold Reference Standard Applied Uniformly. PMID:28955175

Photogrammetry on the identification of postural asymmetries in cadets and pilots of the Brazilian air force academy.

PubMed

Figueiredo, Rodrigo V; Amaral, Artur C; Shimano, Antônio C

2012-01-01

To identify whether flight training activities cause postural changes in cadets and pilots of the Brazilian Air Force Academy (AFA). Eighty subjects were assessed through photographic images in anterior and right side views. Four groups of cadets (n=20 per group) divided according to the year since enlistment and a fifth group of fifteen pilots from the Air Demonstration Squadron (ADS) were included. Pictures were analyzed using the Postural Analysis Program (SAPO) and angles related to head vertical alignment (HVA), head horizontal alignment (HHA), acromion horizontal alignment (AHA) and anterior-superior iliac spine horizontal alignment (HAS) were plotted. We did not find statistical significant differences in the angles: HVA, HHA and AHA. However, a significant difference was found for the HAS angle with pilots having lower values than cadets, suggesting greater postural stability for this variable in pilots. The horizontal alignment of the anterior-superior iliac spine was the only measure that showed significant difference in the comparison between pilots and cadets. The remaining alignments were not different, possibility because of the strict criteria used for admission of cadets at the AFA and the efficiency of the physical training that is performed periodically.

Posture analysis on young women before and after 60 days of -6 degrees head down bed rest (Wise 2005).

PubMed

Viguier, Marion; Dupui, Philippe; Montoya, Richard

2009-02-01

Twenty-four women divided into three groups: control, exercise and nutrition, have been involved in a -6 degrees head down bed rest (HDBR) experiment for 60 days. The objective was to analyse the effects of microgravity on balance function regulation. Group comparisons assessed the efficiency of countermeasures (specific exercises and in particular diet) on the deleterious effects of simulated microgravity. Measurements of orthostatic and dynamic balance were taken 9 and 2 days prior to the experiment, on the first day of getting up, the following day and 4 and 10 days after, under two visual conditions: eyes open and eyes closed. The results confirmed that, as in any other test performed with ordinary subjects, the postural balance performances are better with eyes open than with eyes closed. The static and dynamic postural performances were impaired on the first day of recovery (R0) following HDBR. This impairment lasted up to 4 days after getting up and, afterwards the volunteers recovered their initial performances. The exercise group recovered static postural performances more quickly than the other groups whereas there were no differences in the recovery of the dynamic balance performances.

The foot posture index in men practicing three sports different in their biomechanical gestures.

PubMed

Martínez-Nova, Alfonso; Gómez-Blázquez, Eduardo; Escamilla-Martínez, Elena; Pérez-Soriano, Pedro; Gijon-Nogueron, Gabriel; Fernández-Seguín, Lourdes María

2014-03-01

The technical gestures characteristic of certain sports may lead to one type of foot being more prevalent than the others. The Foot Posture Index (FPI) has been used as a diagnostic tool for support postures in various sports, but the differences in these postures between sports of distinct gestures in their actions are far from completely understood. The overall FPI, obtained as the sum of the scores of its six individual criteria, was determined in 90 male athletes (30 runners, 30 basketball players, and 30 handball players) in static bipedal stance and relaxed position. Analysis of variance was used to find significant differences among the three sports in the total FPI and its six criteria. The mean ± SD FPI was 2.9 ± 2.8 in runners, 3.9 ± 4.1 in basketball players, and -0.4 ± 6.9 in handball players, with significant differences among these groups (P = .008). Significant differences were also found in the talar head position and talonavicular prominence values between handball players and runners (P = .001 and P = .004, respectively) and between handball and basketball players (P = .002 and P = .006, respectively). Runners and basketball players had neutral feet, whereas handball players had supinated feet. The differences in foot posture seem to be mainly determined by two of the FPI criteria: talar head position and talonavicular prominence.

Chosen postures during specific sitting activities.

PubMed

Kamp, Irene; Kilincsoy, Umit; Vink, Peter

2011-11-01

This research study analysed the interaction between people's postures and activities while in semi-public/leisure situations and during transportation (journey by train). In addition, the use of small electronic devices received particular emphasis. Video recordings in German trains and photographs in Dutch semi-public spaces were analysed using a variation of Branton and Grayson's (An evaluation of train seats by observation of sitting behaviour. Ergonomics, 10 (1), (1967), 35-51) postural targeting forms and photos. The analysis suggests a significant relationship between most activities and the position of the head, trunk and arms during transportation situations. The relationship during public situations is less straightforward. Watching, talking/discussing and reading were the most observed activities for the transportation and leisure situations combined. Surprisingly, differences in head, trunk, arm and leg postures were not significant when using small electronic devices. Important issues not considered in this study include the duration of the activities, the gender and age of observed subjects and the influence of the time of day. These are interesting issues to consider and include for future research. STATEMENT OF RELEVANCE: This study shows what activities people choose to carry out and their related postures when not forced to a specific task (e.g. driving). The results of this study can be used for designing comfortable seating in the transportation industry (car passenger, train, bus and aircraft seats) and semi-public/leisure spaces.

Thermal effects of dorsal head immersion in cold water on nonshivering humans.

PubMed

Giesbrecht, Gordon G; Lockhart, Tamara L; Bristow, Gerald K; Steinman, Allan M

2005-11-01

Personal floatation devices maintain either a semirecumbent flotation posture with the head and upper chest out of the water or a horizontal flotation posture with the dorsal head and whole body immersed. The contribution of dorsal head and upper chest immersion to core cooling in cold water was isolated when the confounding effect of shivering heat production was inhibited with meperidine (Demerol, 2.5 mg/kg). Six male volunteers were immersed four times for up to 60 min, or until esophageal temperature = 34 degrees C. An insulated hoodless dry suit or two different personal floatation devices were used to create four conditions: 1) body insulated, head out; 2) body insulated, dorsal head immersed; 3) body exposed, head (and upper chest) out; and 4) body exposed, dorsal head (and upper chest) immersed. When the body was insulated, dorsal head immersion did not affect core cooling rate (1.1 degrees C/h) compared with head-out conditions (0.7 degrees C/h). When the body was exposed, however, the rate of core cooling increased by 40% from 3.6 degrees C/h with the head out to 5.0 degrees C/h with the dorsal head and upper chest immersed (P < 0.01). Heat loss from the dorsal head and upper chest was approximately proportional to the extra surface area that was immersed (approximately 10%). The exaggerated core cooling during dorsal head immersion (40% increase) may result from the extra heat loss affecting a smaller thermal core due to intense thermal stimulation of the body and head and resultant peripheral vasoconstriction. Dorsal head and upper chest immersion in cold water increases the rate of core cooling and decreases potential survival time.

[Orthostatic postural tachycardia: study of 8 patients].

PubMed

Santiago Pérez, S; Ferrer Gila, T

1998-02-07

The occurrence of syncopal episodes is a very frequent event. In the absence of a structural systemic or cardiac disease, syncope is resulting of an anomalous cardiovascular response neurally mediated by the autonomic nervous system. It is the final common manifestation of different abnormal mechanisms and is frequently precipitated by orthostatism. Orthostatic intolerance syndrome refers to the development of symptoms during the upright posture that disappear in supine position. Tachycardia may be one of the clinical features of the syndrome. During orthostatic stress a hyperadrenergic response, with maintained increment of heart rate and associated symptoms, is developed. Changes in blood pressure may be diverse and in some cases hypotension and syncope occurs. Eight patients with symptoms of orthostatic intolerance who underwent autonomic evaluation and were diagnosed from postural tachycardia are presented. In all the cases an abnormal increment of heart rate during tilting was found and it was associated to hyperadrenergic symptoms. Evidence of restricted sympathetic impairment was observed in six cases with distal reduction of sudomotor function and abnormal adrenergic response during Valsalva manoeuvre. Symptoms disappeared or mostly subsided with pharmacological (amitriptyline in one case, phenobarbital in another one and non-cardioselective beta-blockers in six patients) and non-pharmacological treatment. In further examinations heart rate and blood pressure were normal.

Fetal MRI: head and neck.

PubMed

Mirsky, David M; Shekdar, Karuna V; Bilaniuk, Larissa T

2012-08-01

Abnormalities of the fetal head and neck may be seen in isolation or in association with central nervous system abnormalities, chromosomal abnormalities, and syndromes. Magnetic resonance imaging (MRI) plays an important role in detecting associated abnormalities of the brain as well as in evaluating for airway obstruction that may impact prenatal management and delivery planning. This article provides an overview of the common indications for MRI of the fetal head and neck, including abnormalities of the fetal skull and face, masses of the face and neck, and fetal goiter. Copyright © 2012 Elsevier Inc. All rights reserved.

[Pure akinesia presenting with antecollis].

PubMed

Ota, Satoru; Tsuchiya, Kuniaki

2005-10-01

We reported a 77-year-old woman having pure akinesia who presented with antecollis induced by L-threo-3, 4-dihydroxyphenylserine (L-DOPS). At the age of 70, she noticed increasing difficulty in standing up from a seat and moving. Afterward, she developed gait disturbance with difficulty in initiating walking, frozen gait, and postural instability. At 73 years of age, she came to our hospital, because she gradually fell down easily. Neurological examination disclosed mild akinesia with freezing symptom and kinésie paradoxale. No evidence of dementia, supranuclear gaze palsy, pseudobulbar palsy, rigidity, or tremor were present. As she developed akinesia, of which L-dopa therapy achieved little improvement, we clinically diagnosed as having pure akinesia. At age 74, L-DOPS was administered at a dose of 300mg per day and gradually increased up to 900mg per day, because her postural reflex was markedly disturbed and gait showed severe unsteadiness. Amelioration of frozen gait and unsteadiness were recognized, but efficacy of L-DOPS was temporal. It is well known that reported cases of pure akinesia were pathologically diagnosed as having progressive supranuclear palsy (PSP) or pallido-nigro-luysian atrophy. Therefore, the present case was suspected as having pathological changes which involved degeneration of the substantia nigra and globus pallidus. After three years of treatment with L-DOPS, at age 77, she was admitted to our hospital for abrupt onset of her dropped head. Hematological examinations were normal, cervical MRI showed no evidence of paracervical muscular atrophy, and electromyography did not demonstrate any abnormal change. In addition, her posterior cervical muscles showed abnormally high tension, so the dropped head was considered due to antecollis. After admission, antecollis disappeared rapidly following discontinuation of L-DOPS. However the mechanism of drug induced dystonia is imperfectly understood on the basis of the clinical course, L-DOPS was considered as possible cause of her antecollis. L-DOPS, artificial precursor of noradrenarine (NA), is thought to increase not only NA level in the CNS, but also inhibit release of acetylcholine. It is suggested that the antecollis of present case results from impairment of a normal dopaminergic-noradorenergic balance caused by increased NA and striatal dopamine deficiency. This is the first case of antecollis induced by L-DOPS in a pure akinesia patient, providing important information on mechanism of drug induced dystonia and indicating caution in the clinical use of L-DOPS.

Coupling of fingertip somatosensory information to head and body sway

NASA Technical Reports Server (NTRS)

Jeka, J. J.; Schoner, G.; Dijkstra, T.; Ribeiro, P.; Lackner, J. R.

1997-01-01

Light touch contact of a fingertip with a stationary surface can provide orientation information that enhances control of upright stance. Slight changes in contact force at the fingertip provide sensory cues about the direction of body sway, allowing attenuation of sway. In the present study, we asked to which extent somatosensory cues are part of the postural control system, that is, which sensory signal supports this coupling? We investigated postural control not only when the contact surface was stationary, but also when it was moving rhythmically (from 0.1 to 0.5 Hz). In doing so, we brought somatosensory cues from the hand into conflict with other parts of the postural control system. Our focus was the temporal relationship between body sway and the contact surface. Postural sway was highly coherent with contact surface motion. Head and body sway assumed the frequency of the moving contact surface at all test frequencies. To account for these results, a simple model was formulated by approximating the postural control system as a second-order linear dynamical system. The influence of the touch stimulus was captured as the difference between the velocity of the contact surface and the velocity of body sway, multiplied by a coupling constant. Comparison of empirical results (relative phase, coherence, and gain) with model predictions supports the hypothesis of coupling between body sway and touch cues through the velocity of the somatosensory stimulus at the fingertip. One subject, who perceived movement of the touch surface, demonstrated weaker coupling than other subjects, suggesting that cognitive mechanisms introduce flexibility into the postural control scheme.

Effect of body posture on involuntary swallow in healthy volunteers.

PubMed

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.

Facilitation handlings induce increase in electromyographic activity of muscles involved in head control of cerebral palsy children.

PubMed

Simon, Anelise de Saldanha; do Pinho, Alexandre Severo; Grazziotin Dos Santos, Camila; Pagnussat, Aline de Souza

2014-10-01

This study aimed to investigate the electromyographic (EMG) activation of the main cervical muscles involved in the head control during two postures widely used for the facilitation of head control in children with Cerebral Palsy (CP). A crossover trial involving 31 children with clinical diagnosis of CP and spastic quadriplegia was conducted. Electromyography was used to measure muscular activity in randomized postures. Three positions were at rest: (a) lateral decubitus, (b) ventral decubitus on the floor and (c) ventral decubitus on the wedge. Handlings for facilitating the head control were performed using the hip joint as key point of control in two postures: (a) lateral decubitus and (b) ventral decubitus on wedge. All children underwent standardized handlings, performed by the same researcher with experience in the neurodevelopmental treatment. EMG signal was recorded from muscles involved in the head control (paraspinal and sternocleidomastoid muscles) in sagittal, frontal and transverse planes, at the fourth cervical vertebra (C4), tenth thoracic vertebra (T10) and sternocleidomastoid muscle (SCM) levels. The results showed a significant increase in muscle activation when handling was performed in the lateral decubitus at C4 (P<0.001), T10 (P<0.001) and SCM (P=0.02) levels. A significant higher muscle activation was observed when handling was performed in lateral decubitus when compared to ventral decubitus at C4 level (P<0.001). Handling in ventral decubitus also induced an increase in EMG activation at T10 (P=0.018) and SCM (P=0.004) levels but not at C4 level (P=0.38). In conclusion, handlings performed in both positions may induce the facilitation of head control, as evaluated by the activity of cervical and upper trunk muscles. Handling performed in lateral decubitus may induce a slightly better facilitation of head control. These findings contribute to evidence-based physiotherapy practice for the rehabilitation of severely spastic quadriplegic CP children. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Correlates between Munich Functional Development Diagnostics and postural reactivity findings based on seven provovoked postural reactions modus Vojta during the first period of child's life].

PubMed

Gajewska, Ewa; Sobieska, Magdalena; Samborski, Włodzimierz

2006-01-01

This work presents two diagnostic methods which were used to examine 57 children during their first three months of life. By classifying abnormalities of central nervous coordination we compared seven postural reactions according to Vojta with spontaneous behaviour of the child according to Munich Functional Development Diagnostics. It was demonstrated that both methods for the detection of early lesions in the central nervous system are sensitive. Good coherence of the results suggests that both methods may be used interchangeably.

Experimental procedure for measuring and comparing head-neck-trunk posture and movements caused by different progressive addition lens designs.

PubMed

Mateo, B; Porcar-Seder, R; Solaz, J S; Dürsteler, J C

2010-07-01

This study demonstrates that appropriate measurement procedures can detect differences in head movement in a near reading task when using three different progressive addition lenses (PALs). The movements were measured using an anatomical reference system with a biomechanical rationale. This reference system was capable of representing rotations for comparing head flexion relative to trunk, head flexion relative to neck, head rotation relative to trunk and trunk flexion. The subject sample comprised 31 volunteers and three PAL designs with different viewing zones were selected. Significant differences were found between the lenses for three of the seven movement parameters examined. The differences occurred for both vertical and horizontal head movements and could be attributed to aspects of the PAL design. The measurement of the complete kinematic trunk-neck-head chain improved the number of differences that were found over those in previous studies. STATEMENT OF RELEVANCE: The study proposes a methodology based on a biomechanical rationale able to differentiate head-neck-trunk posture and movements caused by different progressive addition lens designs with minimum invasiveness. This methodology could also be applied to analyse the ergonomics of other devices that restrict the user's field of view, such as helmets, personal protective equipment or helmet-mounted displays for pilots. This analysis will allow designers to optimise designs offering higher comfort and performance.

The head and neck discomfort of autonomic failure: an unrecognized aetiology of headache

NASA Technical Reports Server (NTRS)

Robertson, D.; Kincaid, D. W.; Haile, V.; Robertson, R. M.

1994-01-01

Information concerning the frequency, severity, character, location, duration, diurnal pattern of headache and ancillary symptoms were obtained in 25 patients with autonomic failure and 44 control subjects. Precipitating and ameliorating factors were identified. Autonomic failure patients had more head and neck discomfort than controls. Their discomfort was much more likely to localize in the occiput, nape of the neck and shoulder, compared with controls. There was a greater tendency for the discomfort to occur in the morning and after meals. It was sometimes less than 5 min in duration and was often associated with dimming, blurring, or tunnelling of vision. It was provoked by upright posture and relieved by lying down. Patients with severe autonomic failure and orthostatic hypotension often present with a posture-dependent headache or neck pain. Because the relationship of these symptoms to posture is often not recognized, the fact that these findings may signal an underlying autonomic disorder is underappreciated, and the opportunity to consider this aetiology for the headache may be missed.

Postural control in restless legs syndrome with medication intervention using pramipexole.

PubMed

Ahlgrén-Rimpiläinen, Aulikki; Lauerma, Hannu; Kähkönen, Seppo; Aalto, Heikki; Tuisku, Katinka; Holi, Matti; Pyykkö, Ilmari; Rimpiläinen, Ilpo

2014-02-01

Central dopamine regulation is involved in postural control and in the pathophysiology of restless legs syndrome (RLS) and Parkinson's disease (PD). Postural control abnormalities have been detected in PD, but there are no earlier studies with regard to RLS and postural control. Computerized force platform posturography was applied to measure the shift and the velocity (CPFV) of center point of forces (CPF) with eyes open (EO) and eyes closed (EC) in controls (n = 12) and prior and after a single day intervention with pramipexole in RLS subjects (n = 12). CPFV (EO) was significantly lower in the RLS group (p < 0.05) than in controls. After pramipexole intake, the difference disappeared and the subjective symptom severity diminished. Pramipexole did not significantly influence CPFV (EC) or CPF shift direction. Subjects with RLS used extensively visual mechanisms to control vestibule-spinal reflexes to improve or compensate the postural stability. Further research is needed to clarify altered feedback in the central nervous system and involvement of dopamine and vision in the postural control in RLS.

Ergon-trial: ergonomic evaluation of single-port access versus three-port access video-assisted thoracic surgery.

PubMed

Bertolaccini, Luca; Viti, Andrea; Terzi, Alberto

2015-10-01

Single-port access video-assisted thoracic surgery (VATS), a technique progressively developed from the standard three-port approach in minimally invasive surgery, offers ergonomic advantages but also new challenges for the surgeon. We compared the ergonomics of three-port versus single-port VATS. Posture analysis of surgeons was evaluated during 100 consecutive VATS wedge resections (50 triportal vs. 50 uniportal). Technically demanding procedures (major lung resection) were excluded. Operating table height, monitor height, distance and inclination were adjusted according to operator preference. Body posture was assessed by measuring head-trunk axial rotation and head flexion. Perceived physical strain was self-evaluated on the Borg Category Ratio (CR-10) scale. Mental workload was assessed with the National Aeronautics Space Administration-Task Load indeX (NASA-TLX), a multidimensional tool that rates workloads on six scales (mental, physical and temporal demand; effort; performance; frustration). All procedures were completed without complications. Head-trunk axial rotation was significantly reduced and neck flexion significantly improved in uniportal VATS. Viewing direction significantly declined (p = 0.01), body posture as measured on the Borg CR-10 scale was perceived as more stressful and the NASA-TLX score for overall workload was higher (p = 0.04) during triportal VATS. The NASA-TLX score for frustration was higher with uniportal VATS (p = 0.02), but the score for physical demand was higher in triportal VATS (p = 0.006). The surgeon can maintain a more neutral body posture during uniportal VATS by standing straight and facing the monitor with only minimal neck extension/rotation; however, frustration is greater than with triportal VATS.

Postural analysis of eight university student wheelchair users when performing written exercises in their classroom: a case study in Santiago de Cali, Colombia.

PubMed

Martínez, David Leonardo Hurtado; Rodríguez, Wilfredo Ágredo

2012-01-01

In students with physical disabilities, the more energy and time required and invested into finding a good posture, the longer the learning process takes. For this reason, the objective of this study was to characterize the posture in the act of writing of wheelchair users in a classroom. Eight students, (three women) aged 18-40, of some of the main universities of the city of Santiago de Cali participated. An observational field study filming of approximately 10 minutes was done while they took notes in their classes. Posture of the head, trunk, and upper extremities was analyzed with respect to its axis and the type of movement in each joint. The postures were classified depending on the location of support surface finding five different postures in the eight students. In these five postures some biomechanical risk factors, usually present in wheelchair users, are increased when they are associated with those postures. Those associated risk factors are: possible disc spine deformation, muscular stress and causing of pressure ulcer. In conclusion, in four of these five postures a poor interaction among person, task and work desk was observed. Therefore, seven of the eight students in this study were found to have a posture that could be considered risky.

The posture of adolescent male handball players: A two-year study.

PubMed

Grabara, Małgorzata

2018-02-06

Young athletes at the stage of growth acceleration tend to exhibit increased susceptibility to postural abnormalities, especially in the trunk region. The aim of this study was to assess and compare the posture in male adolescent handball players over two years of regular training sessions. The study group comprised 21 handball players. At the start of the study 15 participants were aged 14 and 6 participants were aged 15 (mean 14.25 ± 0.58). The measurements were repeated three times. Posture was assessed with a photogrammetric method based on the moiré phenomenon. The analysis of posture relative to symmetry in the frontal and transverse planes did not reveal any significant differences between posture indicators obtained during the successive measurements. Sagittal plane posture indicators revealed significant changes in torso forward inclination angle and the shape of anteroposterior spinal curvatures. The latter consisted of significant deepening of the upper thoracic curve (angle α) and flattening of the lumbosacral curve (angle γ). A two-year period of handball training did not result in posture asymmetries in young male handball players. The observed changes in the shape of anteroposterior spinal curvatures might be related both to sports training and somatic parameters.

Art and dystonia.

PubMed

Garcia-Ruiz, Pedro J; Slawek, Jaroslaw; Sitek, Emilia J; Martinez Castrillo, Juan Carlos

2015-09-15

Dystonia has a recent history in medicine. Focal dystonia was described in the 19th century by classic authors including Gowers, whilst generalized dystonia was described at the turn of the century. However, it is possible to find precise descriptions of dystonia in art, centuries before the medical definition. We have reviewed several pieces of art (sculpture, painting and literature) across the history that might represent descriptions of dystonia, from ancient period to nowadays. In classic times, the first reference to abnormal postures can be tracked back to the new Empire of Egypt (equinus foot), not to mention some recently described examples of dystonia from the Moche sculptures in Peru or Veracruz culture from Mexico. In Middle Ages it is possible to find many examples of sculptures in European cathedrals representing peasants with dramatic, presumably dystonic postures that coexist with amputation of limbs. This unique combination of dystonia and limb amputation probably represents ergotism. The painters Brueghel, Ribera and Velazquez also represented figures with postures likely to be dystonic. Literature is also a source of precise pre-neurological descriptions, especially during the 19th century. In David Copperfield, Dickens depicts characters with generalized dystonia (Uriah Heep), cervical dystonia (Mr. Sharp) and spasmodic dysphonia (Mr Creakle). Finally, even in modern Art (19th and 20th centuries), there are dramatic descriptions of abnormal postures that are likely to be dystonic, such as painful cervical dystonia (Brancusi), cervical dystonia with sensory trick (Modigliani) and upper limb dystonia (Wyspianski). However some postures presented in works of art may simply be a form of artistic expression and only bear unintentional resemblance to the dystonic postures. Art may be a source of neurological information, and that includes primary and secondary dystonia. Copyright © 2015 Elsevier B.V. All rights reserved.

Out-of-Position Rear Impact Tissue-Level Investigation Using Detailed Finite Element Neck Model.

PubMed

Shateri, Hamed; Cronin, Duane S

2015-01-01

Whiplash injuries can occur in automotive crashes and may cause long-term health issues such as neck pain, headache, and visual and auditory disturbance. Evidence suggests that nonneutral head posture can significantly increase the potential for injury in a given impact scenario, but epidemiological and experimental data are limited and do not provide a quantitative assessment of the increased potential for injury. Although there have been some attempts to evaluate this important issue using finite element models, none to date have successfully addressed this complex problem. An existing detailed finite element neck model was evaluated in nonneutral positions and limitations were identified, including musculature implementation and attachment, upper cervical spine kinematics in axial rotation, prediction of ligament failure, and the need for repositioning the model while incorporating initial tissue strains. The model was enhanced to address these issues and an iterative procedure was used to determine the upper cervical spine ligament laxities. The neck model was revalidated using neutral position impacts and compared to an out-of-position cadaver experiment in the literature. The effects of nonneutral position (axial head rotation) coupled with muscle activation were studied at varying impact levels. The laxities for the ligaments of the upper cervical spine were determined using 4 load cases and resulted in improved response and predicted failure loads relative to experimental data. The predicted head response from the model was similar to an experimental head-turned bench-top rear impact experiment. The parametric study identified specific ligaments with increased distractions due to an initial head-turned posture and the effect of active musculature leading to reduced ligament distractions. The incorporation of ligament laxity in the upper cervical spine was essential to predict range of motion and traumatic response, particularly for repositioning of the neck model prior to impact. The results of this study identify a higher potential for injury in out-of-position rear collisions and identified at-risk locations based on ligament distractions. The model predicted higher potential for injury by as much as 50% based on ligament distraction for the out-of-position posture and reduced potential for injury with muscle activation. Importantly, this study demonstrated that the location of injury or pain depends on the initial occupant posture, so that both the location of injury and kinematic threshold may vary when considering common head positions while driving.

Postural orientation and equilibrium: what do we need to know about neural control of balance to prevent falls?

PubMed

Horak, Fay B

2006-09-01

Postural control is no longer considered simply a summation of static reflexes but, rather, a complex skill based on the interaction of dynamic sensorimotor processes. The two main functional goals of postural behaviour are postural orientation and postural equilibrium. Postural orientation involves the active alignment of the trunk and head with respect to gravity, support surfaces, the visual surround and internal references. Sensory information from somatosensory, vestibular and visual systems is integrated, and the relative weights placed on each of these inputs are dependent on the goals of the movement task and the environmental context. Postural equilibrium involves the coordination of movement strategies to stabilise the centre of body mass during both self-initiated and externally triggered disturbances of stability. The specific response strategy selected depends not only on the characteristics of the external postural displacement but also on the individual's expectations, goals and prior experience. Anticipatory postural adjustments, prior to voluntary limb movement, serve to maintain postural stability by compensating for destabilising forces associated with moving a limb. The amount of cognitive processing required for postural control depends both on the complexity of the postural task and on the capability of the subject's postural control system. The control of posture involves many different underlying physiological systems that can be affected by pathology or sub-clinical constraints. Damage to any of the underlying systems will result in different, context-specific instabilities. The effective rehabilitation of balance to improve mobility and to prevent falls requires a better understanding of the multiple mechanisms underlying postural control.

Relationship between antigravity control and postural control in young children.

PubMed

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.

Workstation design in carpet hand-weaving operation: guidelines for prevention of musculoskeletal disorders.

PubMed

Choobineh, Alireza; Lahmi, Mohammadali; Hosseini, Mostafa; Shahnavaz, Houshang; Jazani, Reza Khani

2004-01-01

Carpet weavers suffer from musculoskeletal problems mainly attributed to poor working postures. Their posture is mostly constrained by the design of workstations. This study was conducted to investigate the effects of 2 design parameters (weaving height and seat type) on postural variables and subjective experience, and to develop guidelines for workstation adjustments. At an experimental workstation, 30 professional weavers worked in 9 different conditions. Working posture and weavers' perceptions were measured. It was shown that head, neck and shoulder postures were influenced by weaving height. Both design parameters influenced trunk and elbows postures. The determinant factor for weavers' perception on the neck, shoulders and elbows was found to be weaving height, and on the back and knees it was seat type. Based on the results, the following guidelines were developed: (a) weaving height should be adjusted to 20 cm above elbow height; (b) a 10 degrees forward-sloping high seat is to be used at weaving workstations.

A pilot investigation into the effects of different office chairs on spinal angles.

PubMed

Annetts, S; Coales, P; Colville, R; Mistry, D; Moles, K; Thomas, B; van Deursen, R

2012-05-01

To investigate the effects of four office chairs on the postural angles of the lumbopelvic and cervical regions. Which chair(s) produce an "ideal" spinal posture? An experimental same subject design was used involving healthy subjects (n = 14) who conducted a typing task whilst sitting on four different office chairs; two "dynamic" chairs (Vari-Kneeler and Swopper), and two static chairs (Saddle and Standard Office with back removed). Data collection was via digital photogrammetry, measuring pelvic and lumbar angles, neck angle and head tilt which were then analysed within MatLab. A repeated measures ANOVA with Bonferroni corrections for multiple comparisons was conducted. Statistically significant differences were identified for posterior pelvic tilt and lumbar lordosis between the Vari-Kneeler and Swopper chairs (p = 0.006, p = 0.001) and the Vari-Kneeler and Standard Office chairs (p = 0.000, 0.000); and also for neck angle and head tilt between the Vari-Kneeler and Swopper chairs (p = 0.000, p = 0.000), the Vari-Kneeler and Saddle chairs (p = 0.002, p = 0.001), the Standard Office and Swopper chairs (p = 0.000, p = 0.000), and the Standard Office and Saddle chairs (p = 0.005, p = 0.001). This study confirms a within region association between posterior pelvic tilt and lumbar lordosis, and between neck angle and head tilt. It was noted that an ideal lumbopelvic position does not always result in a corresponding ideal cervical position resulting in a spinal alignment mismatch. In this study, the most appropriate posture for the lumbopelvic region was produced by the Saddle chair and for the cervical region by both the Saddle and Swopper chairs. No chair consistently produced an ideal posture across all regions, although the Saddle chair created the best posture of those chairs studied. Chair selection should be based on individual need.

Bone microvascular flow differs from skin microvascular flow in response to head-down tilt.

PubMed

Howden, Michelle; Siamwala, Jamila H; Hargens, Alan R

2017-10-01

Loss of hydrostatic pressures in microgravity may alter skin and bone microvascular flows in the lower extremities and potentially reduce wound healing and bone fracture repair. The purpose of this study was to determine the rate at which skin and bone microvascular flows respond to head-down tilt (HDT). We hypothesized that microvascular flows in tibial bone and overlying skin would increase at different rates during HDT. Tibial bone and skin microvascular flows were measured simultaneously using photoplethysmography (PPG) in a total of 17 subjects during sitting (control posture), supine, 6° HDT, 15° HDT, and 30° HDT postures in random order. With greater angles of HDT, bone microvascular flow increased significantly, but skin microvascular flow did not change. Tibial bone microvascular flow increased from the sitting control posture (0.77 ± 0.41 V) to supine (1.95 ± 1.01 V, P = 0.001) and from supine posture to 15° HDT (3.74 ± 2.43 V, P = 0.004) and 30° HDT (3.91 ± 2.68 V, P = 0.006). Skin microvascular flow increased from sitting (0.703 ± 0.75 V) to supine (2.19 ± 1.72 V, P = 0.02) but did not change from supine posture to HDT ( P = 1.0). We show for the first time that microcirculatory flows in skin and bone of the leg respond to simulated microgravity at different rates. These altered levels of blood perfusion may affect rates of wound and bone fracture healing in spaceflight. NEW & NOTEWORTHY Our data show that bone microvascular flow increases more than cutaneous blood flow with greater degrees of head-down tilt. A higher level of perfusion in bone may give insight into the bone mineral density loss in lower extremities of astronauts and why similar tissue degradation is not observed in the skin of the same areas. Copyright © 2017 the American Physiological Society.

Arterial Pressure Gradients during Upright Posture and 30 deg Head Down Tilt

NASA Technical Reports Server (NTRS)

Sanchez, E. R; William, J. M.; Ueno, T.; Ballard, R. E.; Hargens, A. R.; Holton, Emily M. (Technical Monitor)

1997-01-01

Gravity alters local blood pressure within the body so that arterial pressures in the head and foot are lower and higher, respectively, than that at heart level. Furthermore, vascular responses to local alterations of arterial pressure are probably important to maintain orthostatic tolerance upon return to the Earth after space flight. However, it has been difficult to evaluate the body's arterial pressure gradient due to the lack of noninvasive technology. This study was therefore designed to investigate whether finger arterial pressure (FAP), measured noninvasively, follows a normal hydrostatic pressure gradient above and below heart level during upright posture and 30 deg head down tilt (HDT). Seven healthy subjects gave informed consent and were 19 to 52 years old with a height range of 158 to 181 cm. A Finapres device measured arterial pressure at different levels of the body by moving the hand from 36 cm below heart level (BH) to 72 cm above heart level (AH) in upright posture and from 36 cm BH to 48 cm AH during HDT in increments of 12 cm. Mean FAP creased by 85 mmHg transitioning from BH to AH in upright posture, and the pressure gradient calculated from hydrostatic pressure difference (rho(gh)) was 84 mmHg. In HDT, mean FAP decreased by 65 mmHg from BH to AH, and the calculated pressure gradient was also 65 mmHg. There was no significant difference between the measured FAP gradient and the calculated pressure gradient, although a significant (p = 0.023) offset was seen for absolute arterial pressure in upright posture. These results indicate that arterial pressure at various levels can be obtained from the blood pressure at heart level by calculating rho(gh) + an offset. The offset equals the difference between heart level and the site of measurement. In summary, we conclude that local blood pressure gradients can be measured by noninvasive studies of FAP.

Exposure-response relationships for work-related neck and shoulder musculoskeletal disorders--Analyses of pooled uniform data sets.

PubMed

Nordander, Catarina; Hansson, Gert-Åke; Ohlsson, Kerstina; Arvidsson, Inger; Balogh, Istvan; Strömberg, Ulf; Rittner, Ralf; Skerfving, Staffan

2016-07-01

There is a lack of quantitative data regarding exposure-response relationships between occupational risk factors and musculoskeletal disorders in the neck and shoulders. We explored such relationships in pooled data from a series of our cross-sectional studies. We recorded the prevalence of complaints/discomfort (Nordic Questionnaire) and diagnoses (physical examination) in 33 groups (24 female and 9 male) within which the workers had similar work tasks (3141 workers, of which 817 were males). In representative sub-groups, we recorded postures and velocities of the head (N = 299) and right upper arm (inclinometry; N = 306), right wrist postures and velocities (electrogoniometry; N = 499), and muscular activity (electromyography) in the right trapezius muscle (N = 431) and forearm extensors (N = 206). We also assessed the psychosocial work environment (Job Content Questionnaire). Uni- and multivariate linear meta-regression analysis revealed several statistically significant group-wise associations. Neck disorders were associated with head inclination, upper arm elevation, muscle activity of the trapezius and forearm extensors and wrist posture and angular velocity. Right-side shoulder disorders were associated with head and upper arm velocity, activity in the trapezius and forearm extensor muscles and wrist posture and angular velocity. The psychosocial work environment (low job control, job strain and isostrain) was also associated with disorders. Women exhibited a higher prevalence of neck and shoulder complaints and tension neck syndrome than men, when adjusting for postures, velocities, muscular activity or psychosocial exposure. In conclusion, the analyses established quantitative exposure-response relationships between neck and shoulder disorders and objective measures of the physical workload on the arm. Such information can be used for risk assessment in different occupations/work tasks, to establish quantitative exposure limits, and for the evaluation of preventive measures. Copyright © 2016 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Whiplash-associated disorders affect postural reactions to antero-posterior support surface translations during sitting.

PubMed

Côté, Julie N; Patenaude, Isabelle; St-Onge, Nancy; Fung, Joyce

2009-06-01

Previous studies have shown that individuals with WAD display decreased postural stability during standing and walking tasks. However, their ability to maintain seated upright posture has never been investigated. The objective of this study was to characterize kinematic and electromyographic postural stabilization patterns in individuals with chronic WAD and to compare these patterns with those in an able-bodied control group. Ten individuals with WAD and an age- and gender-matched group of healthy individuals were exposed to sudden forward and backward support surface translations while they were seated. Neck and trunk muscle activity and angular displacements as well as centers of mass (COMs) linear displacements at four levels of the head and trunk were computed. The displacement onset of the combined head, arms and trunk COM was significantly delayed in persons with WAD. However, their peak trunk angles were smaller and were reached sooner. In the WAD group, the activation onset of the lumbar erector spinae was less affected by perturbation direction and the sternocleidomastoid muscle, a neck flexor, showed a trend towards being activated later, compared to the healthy group. These results suggest that individuals with WAD may alter stretch reflex threshold and/or elicit a learned response for pain avoidance that may be direction-specific. Such findings highlight the importance of assessing both spatial and temporal characteristics across different levels of the spinal musculoskeletal system to evaluate multidirectional postural responses in WAD individuals.

The effect of moderate running on foot posture index and plantar pressure distribution in male recreational runners.

PubMed

Escamilla-Martínez, Elena; Martínez-Nova, Alfonso; Gómez-Martín, Beatriz; Sánchez-Rodríguez, Raquel; Fernández-Seguín, Lourdes María

2013-01-01

Fatigue due to running has been shown to contribute to changes in plantar pressure distribution. However, little is known about changes in foot posture after running. We sought to compare the foot posture index before and after moderate exercise and to relate any changes to plantar pressure patterns. A baropodometric evaluation was made, using the FootScan platform (RSscan International, Olen, Belgium), of 30 men who were regular runners and their foot posture was examined using the Foot Posture Index before and after a 60-min continuous run at a moderate pace (3.3 m/sec). Foot posture showed a tendency toward pronation after the 60-min run, gaining 2 points in the foot posture index. The total support and medial heel contact areas increased, as did pressures under the second metatarsal head and medial heel. Continuous running at a moderate speed (3.3 m/sec) induced changes in heel strike related to enhanced pronation posture, indicative of greater stress on that zone after physical activity. This observation may help us understand the functioning of the foot, prevent injuries, and design effective plantar orthoses in sport.

Motion sickness, console video games, and head-mounted displays.

PubMed

Merhi, Omar; Faugloire, Elise; Flanagan, Moira; Stoffregen, Thomas A

2007-10-01

We evaluated the nauseogenic properties of commercial console video games (i.e., games that are sold to the public) when presented through a head-mounted display. Anecdotal reports suggest that motion sickness may occur among players of contemporary commercial console video games. Participants played standard console video games using an Xbox game system. We varied the participants' posture (standing vs. sitting) and the game (two Xbox games). Participants played for up to 50 min and were asked to discontinue if they experienced any symptoms of motion sickness. Sickness occurred in all conditions, but it was more common during standing. During seated play there were significant differences in head motion between sick and well participants before the onset of motion sickness. The results indicate that commercial console video game systems can induce motion sickness when presented via a head-mounted display and support the hypothesis that motion sickness is preceded by instability in the control of seated posture. Potential applications of this research include changes in the design of console video games and recommendations for how such systems should be used.

The relationship between forward head posture and temporomandibular disorders.

PubMed

Lee, W Y; Okeson, J P; Lindroth, J

1995-01-01

This study investigated the relationship between forward head posture and temporomandibular disorder symptoms. Thirty-three temporomandibular disorder patients with predominant complaints of masticatory muscle pain were compared with an age- and gender-matched control group. Head position was measured from photographs taken with a plumb line drawn from the ceiling to the lateral malleolus of the ankle and with a horizontal plane that was perpendicular to the plumb line and that passed through the spinous process of the seventh cervical vertebra. The distances from the plumb line to the ear, to the seventh vertebra, and to the shoulder were measured. Two angles were also measured: (1) ear-seventh cervical vertebra-horizontal plane and (2) eye-ear-seventh cervical vertebra. The only measurement that revealed a statistically significant difference was angle ear-seventh cervical vertebra-horizontal plane. This angle was smaller in the patients with temporomandibular disorders than in the control subjects. In other words, when evaluating the ear position with respect to the seventh cervical vertebra, the head was positioned more forward in the group with temporomandibular disorders than in the control group (P < .05).

Cervicocephalic kinesthetic sensibility and postural balance in patients with nontraumatic chronic neck pain--a pilot study.

PubMed

Palmgren, Per J; Andreasson, Daniel; Eriksson, Magnus; Hägglund, Andreas

2009-06-30

Although cervical pain is widespread, most victims are only mildly and occasionally affected. A minority, however, suffer chronic pain and/or functional impairments. Although there is abundant literature regarding nontraumatic neck pain, little focuses on diagnostic criteria. During the last decade, research on neck pain has been designed to evaluate underlying pathophysiological mechanisms, without noteworthy success. Independent researchers have investigated postural balance and cervicocephalic kinesthetic sensibility among patients with chronic neck pain, and have (in most cases) concluded the source of the problem is a reduced ability in the neck's proprioceptive system. Here, we investigated cervicocephalic kinesthetic sensibility and postural balance among patients with nontraumatic chronic neck pain. Ours was a two-group, observational pilot study of patients with complaints of continuous neck pain during the 3 months prior to recruitment. Thirteen patients with chronic neck pain of nontraumatic origin were recruited from an institutional outpatient clinic. Sixteen healthy persons were recruited as a control group. Cervicocephalic kinesthetic sensibility was assessed by exploring head repositioning accuracy and postural balance was measured with computerized static posturography. Parameters of cervicocephalic kinesthetic sensibility were not reduced. However, in one of six test movements (flexion), global repositioning errors were significantly larger in the experimental group than in the control group (p < .05). Measurements did not demonstrate any general impaired postural balance, and varied substantially among participants in both groups. In patients with nontraumatic chronic neck pain, we found statistically significant global repositioning errors in only one of six test movements. In this cohort, we found no evidence of impaired postural balance.Head repositioning accuracy and computerized static posturography are imperfect measures of functional proprioceptive impairments. Validity of (and procedures for using) these instruments demand further investigation. Current Controlled Trials ISRCTN96873990.

The effect of backpack weight on the standing posture and balance of schoolgirls with adolescent idiopathic scoliosis and normal controls.

PubMed

Chow, Daniel H K; Kwok, Monica L Y; Cheng, Jack C Y; Lao, Miko L M; Holmes, Andrew D; Au-Yang, Alexander; Yao, Fiona Y D; Wong, M S

2006-10-01

Concerns have been raised regarding the effect of carrying a backpack on adolescent posture and balance, but the effect of backpack loading combined with other factors affecting balance, such as adolescent idiopathic scoliosis (AIS), has not been determined. This study examines the effects of backpack load on the posture and balance of schoolgirls with AIS and normal controls. The standing posture of 26 schoolgirls with mild AIS (mean age 13, Cobb angle 10-25 degrees ) and 20 age-matched normal schoolgirls were recorded without a backpack and while carrying a standard dual-strap backpack loaded at 7.5%, 10%, 12.5% and 15% of the subject's bodyweight (BW). Kinematics of the pelvis, trunk and head were recorded using a motion analysis system and centre of pressure (COP) data were recorded using a force platform. Reliable COP data could only be derived for 13 of the subjects with AIS. Increasing backpack load causes a significantly increased flexion of the trunk in relation to the pelvis and extension of the head in relation to the trunk, as well as increased antero-posterior range of COP motion. While backpack load appears to affect balance predominantly in the antero-posterior direction, differences between groups were more evident in the medio-lateral direction, with AIS subjects showing poor balance in this direction. Overall, carrying a backpack causes similar sagittal plane changes in posture and balance in both normal and AIS groups. Load size or subject group did not influence balance, but the additive effect of backpack carrying and AIS on postural control alters the risk of fall in this population. Therefore, load limit recommendations based on normal subjects should not be applicable to subjects with AIS.

Visuo-proprioceptive interactions in degenerative cervical spine diseases requiring surgery.

PubMed

Freppel, S; Bisdorff, A; Colnat-Coulbois, S; Ceyte, H; Cian, C; Gauchard, G; Auque, J; Perrin, P

2013-01-01

Cervical proprioception plays a key role in postural control, but its specific contribution is controversial. Postural impairment was shown in whiplash injuries without demonstrating the sole involvement of the cervical spine. The consequences of degenerative cervical spine diseases are underreported in posture-related scientific literature in spite of their high prevalence. No report has focused on the two different mechanisms underlying cervicobrachial pain: herniated discs and spondylosis. This study aimed to evaluate postural control of two groups of patients with degenerative cervical spine diseases with or without optokinetic stimulation before and after surgical treatment. Seventeen patients with radiculopathy were recruited and divided into two groups according to the spondylotic or discal origin of the nerve compression. All patients and a control population of 31 healthy individuals underwent a static posturographic test with 12 recordings; the first four recordings with the head in 0° position: eyes closed, eyes open without optokinetic stimulation, with clockwise and counter clockwise optokinetic stimulations. These four sensorial situations were repeated with the head rotated 30° to the left and to the right. Patients repeated these 12 recordings 6weeks postoperatively. None of the patients reported vertigo or balance disorders before or after surgery. Prior to surgery, in the eyes closed condition, the herniated disc group was more stable than the spondylosis group. After surgery, the contribution of visual input to postural control in a dynamic visual environment was reduced in both cervical spine diseases whereas in a stable visual environment visual contribution was reduced only in the spondylosis group. The relative importance of visual and proprioceptive inputs to postural control varies according to the type of pathology and surgery tends to reduce visual contribution mostly in the spondylosis group. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

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

PubMed

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.

Effects of postural changes and removal of vestibular inputs on blood flow to and from the hindlimb of conscious felines

PubMed Central

Yavorcik, K. J.; Reighard, D. A.; Misra, S. P.; Cotter, L. A.; Cass, S. P.; Wilson, T. D.

2009-01-01

Considerable data show that the vestibular system contributes to blood pressure regulation. Prior studies reported that lesions that eliminate inputs from the inner ears attenuate the vasoconstriction that ordinarily occurs in the hindlimbs of conscious cats during head-up rotations. These data led to the hypothesis that labyrinthine-deficient animals would experience considerable lower body blood pooling during head-up postural alterations. The present study tested this hypothesis by comparing blood flow though the femoral artery and vein of conscious cats during 20–60° head-up tilts from the prone position before and after removal of vestibular inputs. In vestibular-intact animals, venous return from the hindlimb dropped considerably at the onset of head-up tilts and, at 5 s after the initiation of 60° rotations, was 66% lower than when the animals were prone. However, after the animals were maintained in the head-up position for another 15 s, venous return was just 33% lower than before the tilt commenced. At the same time point, arterial inflow to the limb had decreased 32% from baseline, such that the decrease in blood flow out of the limb due to the force of gravity was precisely matched by a reduction in blood reaching the limb. After vestibular lesions, the decline in femoral artery blood flow that ordinarily occurs during head-up tilts was attenuated, such that more blood flowed into the leg. Contrary to expectations, in most animals, venous return was facilitated, such that no more blood accumulated in the hindlimb than when labyrinthine signals were present. These data show that peripheral blood pooling is unlikely to account for the fluctuations in blood pressure that can occur during postural changes of animals lacking inputs from the inner ear. Instead, alterations in total peripheral resistance following vestibular dysfunction could affect the regulation of blood pressure. PMID:19793952

Comparison of Biodynamic Responses in Standing and Seated Human Bodies

NASA Astrophysics Data System (ADS)

MATSUMOTO, Y.; GRIFFIN, M. J.

2000-12-01

The dynamic responses of the human body in a standing position and in a sitting position have been compared. The apparent mass and transmissibilities to the head, six locations along the spine, and the pelvis were measured with eight male subjects exposed to vertical whole-body vibration. In both postures, the principal resonance in the apparent mass occurred in the range 5-6 Hz, with slightly higher frequencies and lower apparent mass in the standing posture. There was greater transmission of vertical vibration to the pelvis and the lower spine and greater relative motion within the lower spine in the standing posture than in the sitting posture at the principal resonance and at higher frequencies. Transmissibilities from the supporting surface (floor or seat) to the thoracic region had similar magnitudes for both standing and sitting subjects. The lumbar spine has less lordosis and may be more compressed and less flexible in the sitting posture than in the standing posture. This may have reduced the relative motions between lumbar vertebrae and both the supporting vibrating surface and the other vertebrae in the sitting posture. The characteristics of the vibration transmitted to the pelvis may have differed in the two postures due to different transmission paths. Increased forward rotation of the pelvis in the standing posture may have caused the differences in responses of the pelvis and the lower spine that were observed between the two postures.

Exploration of the associations of touch-screen tablet computer usage and musculoskeletal discomfort.

PubMed

Chiang, Hsin-Yu Ariel; Liu, Chien-Hsiou

2016-03-10

Tablet users may be at high risk of developing physical discomfort because of their usage behaviors and tablet design. Investigate the usage of tablets, variations in head and neck posture associated with different tablet tilt angles, and the association of tablet use with users' musculoskeletal discomfort. A survey of users' subjective perceptions conducted by questionnaire and measurements of users' postures by a 3D Motion analysis system was used to explore the effects of tablet use. The questionnaire results indicated that over half of the participants reported physical discomfort after using tablets, with the most prevalent discomfort in the neck and shoulders, and more intensity of discomfort for the back although only few participants experienced it. Chi-squared tests indicated that significantly more participants who tended to use tablet computers to play games reported having musculoskeletal discomfort after using a tablet. In addition, preferences for tablet tilt angles varied across tasks (reading and game playing). The results from the 3D motion analysis revealed that head and neck flexion angles were significantly reduced when the tablets were positioned at relatively steep tilt angles. Neck flexion angle was significantly higher in game playing. These data add information regarding to the usage of tablet and its associations with physical discomfort (significantly more participants who tended to use tablet computers to play games reported having musculoskeletal discomfort after using a tablet). Steep tilt angles (such as 60°) may cause tablet users to decrease their head and neck flexion angles, which could lead to a more neutral, effortless, and ergonomically correct posture. Maintaining proper neck posture during active activities such as game playing is recommended to avoid neck discomfort.

Notebook computer use with different monitor tilt angle: effects on posture, muscle activity and discomfort of neck pain users.

PubMed

Chiou, Wen-Ko; Chou, Wei-Ying; Chen, Bi-Hui

2012-01-01

This study aimed to evaluate the posture, muscle activities, and self reported discomforts of neck pain notebook computer users on three monitor tilt conditions: 100°, 115°, and 130°. Six subjects were recruited in this study to completed typing tasks. Results showed subjects have a trend to show the forward head posture in the condition that monitor was set at 100°, and the significant less neck and shoulder discomfort were noted in the condition that monitor was set at 130°. These result suggested neck pain notebook user to set their monitor tilt angle at 130°.

Postural correction reduces hip pain in adult with acetabular dysplasia: A case report.

PubMed

Lewis, Cara L; Khuu, Anne; Marinko, Lee N

2015-06-01

Developmental dysplasia of the hip is often diagnosed in infancy, but less severe cases of acetabular dysplasia are being detected in young active adults. The purpose of this case report is to present a non-surgical intervention for a 31-year-old female with mild acetabular dysplasia and an anterior acetabular labral tear. The patient presented with right anterior hip and groin pain, and she stood with the trunk swayed posterior to the pelvis (swayback posture). The hip pain was reproduced with the anterior impingement test. During gait, the patient maintained the swayback posture and reported 6/10 hip pain. Following correction of the patient's posture, the patient's pain rating was reduced to a 2/10 while walking. The patient was instructed to maintain the improved posture. At the 1 year follow-up, she demonstrated significantly improved posture in standing and walking. She had returned to recreational running and was generally pain-free. The patient demonstrated improvement on self-reported questionnaires for pain, function, and activity. These findings suggest that alteration of posture can have an immediate and lasting effect on hip pain in persons with structural abnormality and labral pathology. Copyright © 2015 Elsevier Ltd. All rights reserved.

Postural correction reduces hip pain in adult with acetabular dysplasia: a case report

PubMed Central

Lewis, Cara L.; Khuu, Anne; Marinko, Lee

2015-01-01

Developmental dysplasia of the hip is often diagnosed in infancy, but less severe cases of acetabular dysplasia are being detected in young active adults. The purpose of this case report is to present a non-surgical intervention for a 31-year-old female with mild acetabular dysplasia and an anterior acetabular labral tear. The patient presented with right anterior hip and groin pain, and she stood with the trunk swayed posterior to the pelvis (swayback posture). The hip pain was reproduced with the anterior impingement test. During gait, the patient maintained the swayback posture and reported 6/10 hip pain. Following correction of the patient’s posture, the patient’s pain rating was reduced to a 2/10 while walking. The patient was instructed to maintain the improved posture. At the 1 year follow-up, she demonstrated significantly improved posture in standing and walking. She had returned to recreational running and was generally pain-free. The patient demonstrated improvement on self-reported questionnaires for pain, function and activity. These findings suggest that alteration of posture can have an immediate and lasting effect on hip pain in persons with structural abnormality and labral pathology. PMID:25731688

Assessment of postural instability in patients with Parkinson's disease.

PubMed

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.

Abnormal Head Position in Infantile Nystagmus Syndrome

PubMed Central

Noval, Susana; González-Manrique, Mar; Rodríguez-Del Valle, José María; Rodríguez-Sánchez, José María

2011-01-01

Infantile nystagmus is an involuntary, bilateral, conjugate, and rhythmic oscillation of the eyes which is present at birth or develops within the first 6 months of life. It may be pendular or jerk-like and, its intensity usually increases in lateral gaze, decreasing with convergence. Up to 64% of all patients with nystagmus also present strabismus, and even more patients have an abnormal head position. The abnormal head positions are more often horizontal, but they may also be vertical or take the form of a tilt, even though the nystagmus itself is horizontal. The aim of this article is to review available information about the origin and treatment of the abnormal head position associated to nystagmus, and to describe our treatment strategies. PMID:24533187

Coupling of Head and Body Movement with Motion of the Audible Environment

ERIC Educational Resources Information Center

Stoffregen, Thomas A.; Villard, Sebastien; Kim, ChungGon; Ito, Kiyohide; Bardy, Benoit G.

2009-01-01

The authors asked whether standing posture could be controlled relative to audible oscillation of the environment. Blindfolded sighted adults were exposed to acoustic flow in a moving room, and were asked to move so as to maintain a constant distance between their head and the room. Acoustic flow had direct (source) and indirect (reflected)…

Shoulder Impingement Treatment

MedlinePlus

... imbalance in the rotator cuff or scapular muscles, postural abnormalities, shoulder joint instability, or improper training or ... and corrected. Phase Goals Methods Comments I Pain control Limit overhead activity or anything that causes pain. ...

Computer users' postures and associations with workstation characteristics.

PubMed

Gerr, F; Marcus, M; Ortiz, D; White, B; Jones, W; Cohen, S; Gentry, E; Edwards, A; Bauer, E

2000-01-01

This investigation tested the hypotheses that (1) physical workstation dimensions are important determinants of operator posture, (2) specific workstation characteristics systematically affect worker posture, and (3) computer operators assume "neutral" upper limb postures while keying. Operator head, neck, and upper extremity posture and selected workstation dimensions and characteristics were measured among 379 computer users. Operator postures were measured with manual goniometers, workstation characteristics were evaluated by observation, and workstation dimensions by direct measurement. Considerably greater variability in all postures was observed than was expected from application of basic geometric principles to measured workstation dimensions. Few strong correlations were observed between worker posture and workstation physical dimensions; findings suggest that preference is given to keyboard placement with respect to the eyes (r = 0.60 for association between keyboard height and seated elbow height) compared with monitor placement with respect to the eyes (r = 0.18 for association between monitor height and seated eye height). Wrist extension was weakly correlated with keyboard height (r = -0.24) and virtually not at all with keyboard thickness (r = 0.07). Use of a wrist rest was associated with decreased wrist flexion (21.9 versus 25.1 degrees, p < 0.01). Participants who had easily adjustable chairs had essentially the same neck and upper limb postures as did those with nonadjustable chairs. Sixty-one percent of computer operators were observed in nonneutral shoulder postures and 41% in nonneutral wrist postures. Findings suggest that (1) workstation dimensions are not strong determinants of at least several neck and upper extremity postures among computer operators, (2) only some workstation characteristics affect posture, and (3) contrary to common recommendations, a large proportion of computer users do not work in so-called neutral postures.

Effect of a worktable position on head and shoulder posture and shoulder muscles in manual material handling.

PubMed

Kim, Min-Hee; Yoo, Won-Gyu

2015-06-05

According to a recent research, manual working with high levels of static contraction, repetitive loads, or extreme working postures involving the neck and shoulder muscles causes an increased risk of neck and shoulder musculoskeletal disorders. We investigated the effects of the forwardly worktable position on head and shoulder angles and shoulder muscle activity in manual material handling tasks. The forward head and shoulder angles and the activity of upper trapezius, levator scapulae, and middle deltoid muscle activities of 15 workers were measured during performing of manual material handling in two tasks that required different forward head and shoulder angles. The second manual material task required a significantly increased forward head and shoulder angle. The upper trapezius and levator scapulae muscle activity in second manual material task was increased significantly compared with first manual material task. The middle deltoid muscle activity in second manual material task was not significantly different compared with first manual material task. Based on this result, the forward head and shoulder angles while performing manual work need to be considered in selection of the forward distance of a worktable form the body. The high level contractions of the neck and shoulder muscles correlated with neck and shoulder pain. Therefore, the forward distance of a worktable can be an important factor in preventing neck and shoulder pain in manual material handling workers.

Additional helmet and pack loading reduce situational awareness during the establishment of marksmanship posture.

PubMed

Lim, Jongil; Palmer, Christopher J; Busa, Michael A; Amado, Avelino; Rosado, Luis D; Ducharme, Scott W; Simon, Darnell; Van Emmerik, Richard E A

2017-06-01

The pickup of visual information is critical for controlling movement and maintaining situational awareness in dangerous situations. Altered coordination while wearing protective equipment may impact the likelihood of injury or death. This investigation examined the consequences of load magnitude and distribution on situational awareness, segmental coordination and head gaze in several protective equipment ensembles. Twelve soldiers stepped down onto force plates and were instructed to quickly and accurately identify visual information while establishing marksmanship posture in protective equipment. Time to discriminate visual information was extended when additional pack and helmet loads were added, with the small increase in helmet load having the largest effect. Greater head-leading and in-phase trunk-head coordination were found with lighter pack loads, while trunk-leading coordination increased and head gaze dynamics were more disrupted in heavier pack loads. Additional armour load in the vest had no consequences for Time to discriminate, coordination or head dynamics. This suggests that the addition of head borne load be carefully considered when integrating new technology and that up-armouring does not necessarily have negative consequences for marksmanship performance. Practitioner Summary: Understanding the trade-space between protection and reductions in task performance continue to challenge those developing personal protective equipment. These methods provide an approach that can help optimise equipment design and loading techniques by quantifying changes in task performance and the emergent coordination dynamics that underlie that performance.

An analysis of the activity and muscle fatigue of the muscles around the neck under the three most frequent postures while using a smartphone.

PubMed

Choi, Jung-Hyun; Jung, Min-Ho; Yoo, Kyung-Tae

2016-05-01

[Purpose] The purpose of this study was to identify changes in the activity and fatigue of the splenius capitis and upper trapezius muscles, which are agonists to the muscles supporting the head, under the three postures most frequently adopted while using a smartphone. [Subjects and Methods] The subjects were 15 college students in their 20s. They formed a single group and had to adopt three different postures (maximum bending, middle bending, and neutral). While the 15 subjects maintained the postures, muscle activity and fatigue were measured using surface electromyography. [Results] Comparison of the muscle fatigue caused by each posture showed statistically significant differences for the right splenius capitis, left splenius capitis, and left upper trapezius muscles. In addition, maintaining the maximum bending posture while using a smartphone resulted in higher levels of fatigue in the right splenius capitis, left splenius capitis, and left upper trapezius muscles compared with those for the middle bending posture. [Conclusion] Therefore, this study suggests that individuals should bend their neck slightly when using a smartphone, rather than bending it too much, or keep their neck straight to reduce fatigue of the cervical erector muscles.

Independent walking as a major skill for the development of anticipatory postural control: evidence from adjustments to predictable perturbations.

PubMed

Cignetti, Fabien; Zedka, Milan; Vaugoyeau, Marianne; Assaiante, Christine

2013-01-01

Although there is suggestive evidence that a link exists between independent walking and the ability to establish anticipatory strategy to stabilize posture, the extent to which this skill facilitates the development of anticipatory postural control remains largely unknown. Here, we examined the role of independent walking on the infants' ability to anticipate predictable external perturbations. Non-walking infants, walking infants and adults were sitting on a platform that produced continuous rotation in the frontal plane. Surface electromyography (EMG) of neck and lower back muscles and the positions of markers located on the platform, the upper body and the head were recorded. Results from cross-correlation analysis between rectified and filtered EMGs and platform movement indicated that although muscle activation already occurred before platform movement in non-walking infants, only walking infants demonstrated an adult-like ability for anticipation. Moreover, results from further cross-correlation analysis between segmental angular displacement and platform movement together with measures of balance control at the end-points of rotation of the platform evidenced two sorts of behaviour. The adults behaved as a non-rigid non-inverted pendulum, rather stabilizing head in space, while both the walking and non-walking infants followed the platform, behaving as a rigid inverted pendulum. These results suggest that the acquisition of independent walking plays a role in the development of anticipatory postural control, likely improving the internal model for the sensorimotor control of posture. However, despite such improvement, integrating the dynamics of an external object, here the platform, within the model to maintain balance still remains challenging in infants.

A systematic review of the angular values obtained by computerized photogrammetry in sagittal plane: a proposal for reference values.

PubMed

Krawczky, Bruna; Pacheco, Antonio G; Mainenti, Míriam R M

2014-05-01

Reference values for postural alignment in the coronal plane, as measured by computerized photogrammetry, have been established but not for the sagittal plane. The objective of this study is to propose reference values for angular measurements used for postural analysis in the sagittal plane for healthy adults. Electronic databases (PubMed, BVS, Cochrane, Scielo, and Science Direct) were searched using the following key words: evaluation, posture, photogrammetry, and software. Articles published between 2006 and 2012 that used the PAS/SAPO (postural assessment software) were selected. Another inclusion criterion was the presentation of, at least, one of the following measurements: head horizontal alignment, pelvic horizontal alignment, hip angle, vertical alignment of the body, thoracic kyphosis, and lumbar lordosis. Angle samples of the selected articles were grouped 2 by 2 in relation to an overall average, which made possible total average, variance, and SD calculations. Six articles were included, and the following average angular values were found: 51.42° ± 4.87° (head horizontal alignment), -12.26° ± 5.81° (pelvic horizontal alignment), -6.40° ± 3.86° (hip angle), and 1.73° ± 0.94° (vertical alignment of the body). None of the articles contained the measurements for thoracic kyphosis and lumbar lordosis. The reference values can be adopted as reference for postural assessment in future researches if the same anatomical points are considered. Copyright © 2014 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

Impaired perception of surface tilt in progressive supranuclear palsy

PubMed Central

Dale, Marian L.; Horak, Fay B.; Wright, W. Geoffrey; Schoneburg, Bernadette M.; Nutt, John G.; Mancini, Martina

2017-01-01

Introduction Progressive supranuclear palsy (PSP) is characterized by early postural instability and backward falls. The mechanisms underlying backward postural instability in PSP are not understood. The aim of this study was to test the hypothesis that postural instability in PSP is a result of dysfunction in the perception of postural verticality. Methods We gathered posturography data on 12 subjects with PSP to compare with 12 subjects with idiopathic Parkinson’s Disease (PD) and 12 healthy subjects. Objective tests of postural impairment included: dynamic sensory perception tests of gravity and of surface oscillations, postural responses to surface perturbations, the sensory organization test of postural sway under altered sensory conditions and limits of stability in stance. Results Perception of toes up (but not toes down) surface tilt was reduced in subjects with PSP compared to both control subjects (p≤0.001 standing, p≤0.007 seated) and subjects with PD (p≤0.03 standing, p≤0.04 seated). Subjects with PSP, PD and normal controls accurately perceived the direction of gravity when standing on a tilting surface. Unlike PD and control subjects, subjects with PSP exerted less postural corrective torque in response to toes up surface tilts. Discussion Difficulty perceiving backward tilt of the surface or body may account for backward falls and postural impairments in patients with PSP. These observations suggest that abnormal central integration of sensory inputs for perception of body and surface orientation contributes to the pathophysiology of postural instability in PSP. PMID:28267762

Using motion capture technology to measure the effects of magnification loupes on dental operator posture: A pilot study.

PubMed

Branson, B G; Abnos, R M; Simmer-Beck, M L; King, G W; Siddicky, S F

2018-01-01

Motion analysis has great potential for quantitatively evaluating dental operator posture and the impact of interventions such as magnification loupes on posture and subsequent development of musculoskeletal disorders. This study sought to determine the feasibility of motion capture technology for measurement of dental operator posture and examine the impact that different styles of magnification loupes had on dental operator posture. Forward and lateral head flexion were measured for two different operators while completing a periodontal probing procedure. Each was measured while wearing magnification loupes (flip up-FL and through the lens-TTL) and basic safety lenses. Operators both exhibited reduced forward flexion range of motion (ROM) when using loupes (TTL or FL) compared to a baseline lens (BL). In contrast to forward flexion, no consistent trends were observed for lateral flexion between subjects. The researchers can report that it is possible to measure dental operator posture using motion capture technology. More study is needed to determine which type of magnification loupes (FL or TTL) are superior in improving dental operator posture. Some evidence was found supporting that the quality of operator posture may more likely be related to the use of magnification loupes, rather than the specific type of lenses worn.

Upper quadrant postural changes of school children in response to interaction with different information technologies.

PubMed

Briggs, Andrew; Straker, Leon; Greig, Alison

2004-06-10

The objective of this study was to quantitatively analyse the sitting posture of school children interacting with both old (book) and new (laptop and desktop computers) information technologies to test the hypothesis that posture is effected by the type of information technology (IT) used. A mixed model design was used to test the effect of IT type (within subjects) and age and gender (between subjects). The sitting posture of 32 children aged 4-17 years was measured whilst they read from a book, laptop, and desktop computer at a standard school chair and desk. Video images were captured and then digitized to calculate mean angles for head tilt, neck flexion, trunk flexion, and gaze angle. Posture was found to be influenced by IT type (p < 0.001), age (p < 0.001) and gender (p = 0.024) and significantly correlated to the stature of the participants. Measurement of resting posture and the maximal range of motion of the upper and lower cervical spines in the sagittal plane was also undertaken. The biophysical impact and the suitability of the three different information technologies are discussed.

Medication-induced acute dystonic reaction: the challenge of diagnosing movement disorders in the intensive care unit.

PubMed

Digby, Geneviève; Jalini, Shirin; Taylor, Sean

2015-09-21

A 62-year-old man presented with left middle cerebral artery stroke. 1 h postadministration of tissue plasminogen activator, he received a total of 4 mg of haloperidol for combativeness. He developed partial complex status epilepticus, requiring benzodiazepines, phenytoin, propofol and intubation. 5 h later, he developed recurrent stereotyped tonic movements involving arching of the back, extension of the arms and contraction of opposing muscle groups. Repeat CT scan of the head showed evolving insular infarct. Differential diagnoses for these movements included tonic/clonic seizures, extensor (decerebrate) posturing from haemorrhagic conversion, neuroleptic malignant syndrome, or dystonic reaction. Given the lack of response to antiseizure medications, the recent administration of haloperidol, and the prompt resolution of movements following diphenhydramine administration, an acute dystonic reaction was considered. This atypical case of a critically ill patient with stroke highlights the fact that these patients may have multiple abnormal movements requiring careful analysis to guide diagnosis-specific management. 2015 BMJ Publishing Group Ltd.

Megalencephaly

MedlinePlus

... also called megacephaly or megalocephaly), which describes a big head, and which doesn’t necessarily indicate abnormality. ... also called megacephaly or megalocephaly), which describes a big head, and which doesn’t necessarily indicate abnormality. ...

Constrained posture in dentistry - a kinematic analysis of dentists.

PubMed

Ohlendorf, Daniela; Erbe, Christina; Nowak, Jennifer; Hauck, Imke; Hermanns, Ingo; Ditchen, Dirk; Ellegast, Rolf; Groneberg, David A

2017-07-05

How a dentist works, such as the patterns of movements performed daily, is also largely affected by the workstation Dental tasks are often executed in awkward body positions, thereby causing a very high degree of strain on the corresponding muscles. The objective of this study is to detect those dental tasks, during which awkward postures occur most frequently. The isolated analysis of static postures will examine the duration for which these postures are maintained during the corresponding dental, respectively non-dental, activities. 21 (11f/10 m) dentists (age: 40.1 ± 10.4 years) participated in this study. An average dental workday was collected for every subject. To collect kinematic data of all activities, the CUELA system was used. Parallel to the kinematic examination, a detailed computer-based task analysis was conducted. Afterwards, both data sets were synchronized based on the chronological order of the postures assumed in the trunk and the head region. All tasks performed were assigned to the categories "treatment" (I), "office" (II) and "other activities" (III). The angle values of each body region (evaluation parameter) were examined and assessed corresponding to ergonomic standards. Moreover, this study placed a particular focus on static positions, which are held statically for 4 s and longer. For "treatment" (I), the entire head and trunk area is anteriorly tilted while the back is twisted to the right, in (II) and (III) the back is anteriorly tilted and twisted to the right (non-neutral position). Static positions in (I) last for 4-10s, static postures (approx. 60%) can be observed while in (II) and (III) in the back area static positions for more than 30 s are most common. Moreover, in (II) the back is twisted to the right for more than 60 s in 26.8%. Awkward positions are a major part of a dentists' work. This mainly pertains to static positions of the trunk and head in contrast to "office work." These insights facilitate the quantitative description of the dentist profession with regard to the related physical load along with the health hazards to the musculoskeletal system. Moreover, the results allow for a selective extraction of the most unfavorable static body positions that dentists assume for each of the activities performed.

N-Acetyl-L-Leucine Accelerates Vestibular Compensation after Unilateral Labyrinthectomy by Action in the Cerebellum and Thalamus

PubMed Central

Xiong, Guoming; Potschka, Heidrun; Jahn, Klaus; Bartenstein, Peter; Brandt, Thomas; Dutia, Mayank; Dieterich, Marianne; Strupp, Michael; la Fougère, Christian; Zwergal, Andreas

2015-01-01

An acute unilateral vestibular lesion leads to a vestibular tone imbalance with nystagmus, head roll tilt and postural imbalance. These deficits gradually decrease over days to weeks due to central vestibular compensation (VC). This study investigated the effects of i.v. N-acetyl-DL-leucine, N-acetyl-L-leucine and N-acetyl-D-leucine on VC using behavioural testing and serial [18F]-Fluoro-desoxyglucose ([18F]-FDG)-μPET in a rat model of unilateral chemical labyrinthectomy (UL). Vestibular behavioural testing included measurements of nystagmus, head roll tilt and postural imbalance as well as sequential whole-brain [18F]-FDG-μPET was done before and on days 1,3,7 and 15 after UL. A significant reduction of postural imbalance scores was identified on day 7 in the N-acetyl-DL-leucine (p < 0.03) and the N-acetyl-L-leucine groups (p < 0.01), compared to the sham treatment group, but not in the N-acetyl-D-leucine group (comparison for applied dose of 24 mg i.v. per rat, equivalent to 60 mg/kg body weight, in each group). The course of postural compensation in the DL- and L-group was accelerated by about 6 days relative to controls. The effect of N-acetyl-L-leucine on postural compensation depended on the dose: in contrast to 60 mg/kg, doses of 15 mg/kg and 3.75 mg/kg had no significant effect. N-acetyl-L-leucine did not change the compensation of nystagmus or head roll tilt at any dose. Measurements of the regional cerebral glucose metabolism (rCGM) by means of μPET revealed that only N-acetyl-L-leucine but not N-acetyl-D-leucine caused a significant increase of rCGM in the vestibulocerebellum and a decrease in the posterolateral thalamus and subthalamic region on days 3 and 7. A similar pattern was found when comparing the effect of N-acetyl-L-leucine on rCGM in an UL-group and a sham UL-group without vestibular damage. In conclusion, N-acetyl-L-leucine improves compensation of postural symptoms after UL in a dose-dependent and specific manner, most likely by activating the vestibulocerebellum and deactivating the posterolateral thalamus. PMID:25803613

N-acetyl-L-leucine accelerates vestibular compensation after unilateral labyrinthectomy by action in the cerebellum and thalamus.

PubMed

Günther, Lisa; Beck, Roswitha; Xiong, Guoming; Potschka, Heidrun; Jahn, Klaus; Bartenstein, Peter; Brandt, Thomas; Dutia, Mayank; Dieterich, Marianne; Strupp, Michael; la Fougère, Christian; Zwergal, Andreas

2015-01-01

An acute unilateral vestibular lesion leads to a vestibular tone imbalance with nystagmus, head roll tilt and postural imbalance. These deficits gradually decrease over days to weeks due to central vestibular compensation (VC). This study investigated the effects of i.v. N-acetyl-DL-leucine, N-acetyl-L-leucine and N-acetyl-D-leucine on VC using behavioural testing and serial [18F]-Fluoro-desoxyglucose ([18F]-FDG)-μPET in a rat model of unilateral chemical labyrinthectomy (UL). Vestibular behavioural testing included measurements of nystagmus, head roll tilt and postural imbalance as well as sequential whole-brain [18F]-FDG-μPET was done before and on days 1,3,7 and 15 after UL. A significant reduction of postural imbalance scores was identified on day 7 in the N-acetyl-DL-leucine (p < 0.03) and the N-acetyl-L-leucine groups (p < 0.01), compared to the sham treatment group, but not in the N-acetyl-D-leucine group (comparison for applied dose of 24 mg i.v. per rat, equivalent to 60 mg/kg body weight, in each group). The course of postural compensation in the DL- and L-group was accelerated by about 6 days relative to controls. The effect of N-acetyl-L-leucine on postural compensation depended on the dose: in contrast to 60 mg/kg, doses of 15 mg/kg and 3.75 mg/kg had no significant effect. N-acetyl-L-leucine did not change the compensation of nystagmus or head roll tilt at any dose. Measurements of the regional cerebral glucose metabolism (rCGM) by means of μPET revealed that only N-acetyl-L-leucine but not N-acetyl-D-leucine caused a significant increase of rCGM in the vestibulocerebellum and a decrease in the posterolateral thalamus and subthalamic region on days 3 and 7. A similar pattern was found when comparing the effect of N-acetyl-L-leucine on rCGM in an UL-group and a sham UL-group without vestibular damage. In conclusion, N-acetyl-L-leucine improves compensation of postural symptoms after UL in a dose-dependent and specific manner, most likely by activating the vestibulocerebellum and deactivating the posterolateral thalamus.

The vascular basis of the positional influence of the intraocular pressure.

PubMed

Krieglstein, G K; Waller, W K; Leydhecker, W

1978-05-02

By measuring intraocular pressure in different body positions from 60 degrees semiupright to 30 degrees head down, a nonlinear relationship between IOP increase and body position was confirmed. IOP postural response in individual subjects was roughly correlated to ophthalmic arterial pressure and to the episcleral venous pressure postural response. In one series of subjects, the episcleral venous pressure increments due to posture wa; parallel to the applanation-indentation disparity in the same individual eyes. Differential tonometry with applanation or indentation procedures under blind conditions gave significantly low indentation readings. It is concluded that IOP postural response depends on arterial and venous vascular changes when subjects move from an erect to a horizontal body position. Blood expulsion from the choroid by indentation tonometry might be the reason that this tonometric procedure does not measure IOP changes based on vascular changes.

Neck postures in air traffic controllers with and without neck/shoulder disorders.

PubMed

Arvidsson, Inger; Hansson, Gert-Ake; Mathiassen, Svend Erik; Skerfving, Staffan

2008-03-01

Prolonged computer work with an extended neck is commonly believed to be associated with an increased risk of neck-shoulder disorders. The aim of this study was to compare neck postures during computer work between female cases with neck-shoulder disorders, and healthy referents. Based on physical examinations, 13 cases and 11 referents were selected among 70 female air traffic controllers with the same computer-based work tasks and identical workstations. Postures and movements were measured by inclinometers, placed on the forehead and upper back (C7/Th1) during authentic air traffic control. A recently developed method was applied to assess flexion/extension in the neck, calculated as the difference between head and upper back flexion/extension. cases and referents did not differ significantly in neck posture (median neck flexion/extension: -10 degrees vs. -9 degrees ; p=0.9). Hence, the belief that neck extension posture is associated with neck-shoulder disorders in computer work is not supported by the present data.

A study on causes and types of abnormal increase in infants' head circumference in kashan/iran.

PubMed

Talebian, Ahmad; Soltani, Babak; Moravveji, Alireza; Salamati, Ladan; Davami, Majid

2013-01-01

Head circumference is a valuable index of brain growth and its disturbances can indicate different disorders of nervous system. Abnormal increased head circumference (macrocephaly) is common and observed in about 2% of infants. In this study, the causes and clinical types of abnormal increase in infants' head circumference were investigated in Kashan, Iran. This cross-sectional study was performed on 90 infants less than 2 years of age with abnormal increase in head circumference in Kashan, during 2009- 2011. The data were collected by history taking, physical examination, growth chart, and imaging. 65 (72%) cases out of 90 infants were male and 25 ( 28%) cases were female. Fifty-three (58.8%) cases had familial megalencephaly, 30 (33.4%) had hydrocephalus, and other causes were observed in 7 (7.8%) cases. Eighty-three percent of Infants with familial megalencephaly and 50% with hydrocephalus had normal fontanels. In 90.6% of cases with familial megalencephaly, family history for large head was positive. Motor development was normal in 100% of cases with familial megalencephaly and 76.7% of hydrocephalic infants. Familial megalencephaly was the most common cause of macrocephaly in the studied infants, and most of them had normal physical examination and development, so, parental head circumferences should be considered in the interpretation of infant's head circumference and in cases of abnormal physical examination or development, other diagnostic modalities, including brain imaging should be done.

Assessment of the postural control strategies used to play two Wii Fit™ videogames.

PubMed

Michalski, A; Glazebrook, C M; Martin, A J; Wong, W W N; Kim, A J W; Moody, K D; Salbach, N M; Steinnagel, B; Andrysek, J; Torres-Moreno, R; Zabjek, K F

2012-07-01

The Nintendo Wii Fit™ may provide an affordable alternative to traditional biofeedback or virtual reality systems for retraining or improving motor function in populations with impaired balance. The purpose of this study was to evaluate postural control strategies healthy individuals use to play Wii Fit™ videogames. Sixteen young adults played 10 trials of Ski Slalom and Soccer Heading respectively. Centre of pressure (COP) excursion and three-dimensional movement data were acquired to determine variability in medial-lateral COP sway and shoulder-pelvic movement. While there was no difference in medial-lateral COP variability between games during trial 1, there was a significant difference after 10 trials. COP sway increased (59-75 mm) for Soccer Heading while it decreased (67-33 mm) for Ski Slalom from trial 1 to trial 10. During Ski Slalom participants demonstrated decreased shoulder and pelvic movement combined with increased pelvic-shoulder coupling. Conversely, participants demonstrated greater initial shoulder tilt when playing Soccer Heading, with no reduction in pelvic rotation and tilt. Participants decreased pelvic and trunk movements when skiing, suggesting a greater contribution of lower extremity control while they primarily used a trunk strategy to play Soccer Heading. Copyright © 2012 Elsevier B.V. All rights reserved.

The non-motor syndrome of primary dystonia: clinical and pathophysiological implications

PubMed Central

Stamelou, Maria; Edwards, Mark J.; Hallett, Mark

2012-01-01

Dystonia is typically considered a movement disorder characterized by motor manifestations, primarily involuntary muscle contractions causing twisting movements and abnormal postures. However, growing evidence indicates an important non-motor component to primary dystonia, including abnormalities in sensory and perceptual functions, as well as neuropsychiatric, cognitive and sleep domains. Here, we review this evidence and discuss its clinical and pathophysiological implications. PMID:21933808

Exercises to Improve Gait Abnormalities

MedlinePlus

... are so characteristic that they have been given descriptive names: Propulsive gait; a stooped, rigid posture, with ... you! Champion's Rx Inclusive Fitness Coalition UAB/Lakeshore Research Collaborative Facebook Twitter YouTube The information provided in ...

The cam impinging femur has multiple morphologic abnormalities.

PubMed

Ellis, Andrew R; Noble, Philip C; Schroder, Steven J; Thompson, Matthew T; Stocks, Gregory W

2011-09-01

This study was performed to establish whether the "cam" impinging femur has a single deformity of the head-neck junction or multiple abnormalities. Average dimensions (anteversion angle, α angle of Notzli, β angle of Beaulé, normalized anterior head offset) were compared between normal and impinging femora. The results demonstrated that impinging femora had wider necks, larger heads, and decreased head-neck ratios. There was no difference in neck-shaft angle or anteversion angle. Forty-six percent of impinging femora had significant posterior head displacement (>2mm), which averaged 1.93 mm for the cam impinging group, and 0.78 mm for the normal group. In conclusion, surgical treatment limited to localized recontouring of the head-neck profile may fail to address significant components of the underlying abnormality. Copyright © 2011 Elsevier Inc. All rights reserved.

Conservative Management of Uncomplicated Mechanical Neck Pain in a Military Aviator

DTIC Science & Technology

2010-01-01

head to the right. The neck pain became more bothersome during and after ACM. Typically the pain was described as being dull and aching in...outcome of exposure to high gravi- tational (G) forces.2 The weight of the helmet and oxygen mask and the various non-neutral head postures assumed when...character; however it could become sharp with rapid right rotation of the neck or under high G situations. He experienced diffi culty turning his head to

Gestational age

MedlinePlus

... looking at the baby's weight, length, head circumference , vital signs, reflexes, muscle tone, posture, and the condition of the skin and hair. If the baby's gestational age findings after birth match the calendar age, the baby ...

Repetitive head impacts do not affect postural control following a competitive athletic season.

PubMed

Murray, Nicholas G; Grimes, Katelyn E; Shiflett, Eric D; Munkasy, Barry A; D'Amico, Nathan R; Mormile, Megan E; Powell, Douglas W; Buckley, Thomas A

2017-10-03

Evidence suggests that Repetitive Head Impacts (RHI) directly influence the brain over the course of a single contact collision season yet do not significantly impact a player's performance on the standard clinical concussion assessment battery. The purpose of this study was to investigate changes in static postural control after a season of RHI in Division I football athletes using more sensitive measures of postural control as compared to a non-head contact sports. Fourteen Division I football players (CON) (age=20.4±1.12years) and fourteen non-contact athletes (NON) (2 male, 11 female; age=19.85±1.21years) completed a single trial of two minutes of eyes open quiet upright stance on a force platform (1000Hz) prior to athletic participation (PRE) and at the end of the athletic season (POST). All CON athletes wore helmets outfitted with Head Impact Telemetry (HIT) sensors and total number of RHI and linear accelerations forces of each RHI were recorded. Center of pressure root mean square (RMS), peak excursion velocity (PEV), and sample entropy (SampEn) in the anteroposterior (AP) and mediolateral (ML) directions were calculated. CON group experienced 649.5±496.8 mean number of impacts, 27.1±3.0 mean linear accelerations, with ≈1% of total player impacts exceeded 98g over the course of the season. There were no significant interactions for group x time RMS in the AP (p=0.434) and ML (p=0.114) directions, PEV in the AP (p=0.262) and ML (p=0.977) directions, and SampEn in the AP (p=0.499) and ML (p=0.984) directions. In addition, no significant interactions for group were observed for RMS in the AP (p=0.105) and ML (p=0.272) directions, PEV in the AP (p=0.081) and ML (p=0.143) directions, and SampEn in the AP (p=0.583) and ML (p=0.129) directions. These results suggest that over the course of a single competitive season, RHI do not negatively impact postural control even when measured with sensitive non-linear metrics. Copyright © 2017 Elsevier B.V. All rights reserved.

Impaired eye movements in presymptomatic spinocerebellar ataxia type 6.

PubMed

Christova, Peka; Anderson, John H; Gomez, Christopher M

2008-04-01

Early detection of impaired neurological function in neurodegenerative diseases may aid in understanding disease pathogenesis and timing of therapeutic trials. To identify early abnormalities of ocular motor function in individuals who have the spinocerebellar ataxia type 6 (SCA6) gene (CACNA1A) but no clinical symptoms. Physiological techniques were used to record and analyze eye movements and postural sway. Four presymptomatic and 5 ataxic patients with SCA6, genetically identified, and 10 healthy controls. Presymptomatic individuals had normal postural sway but definite ocular motor abnormalities. Two had a low-amplitude horizontal gaze-evoked nystagmus, 1 of whom had a significantly decreased eye velocity for upward saccades and an abnormal frequency of square-wave jerks. Another had abnormal square-wave jerks and a fourth had a reduced gain for pursuit tracking. Not all of the presymptomatic patients had the same findings, but a multivariate analysis discriminated the presymptomatic patients, as a group, from healthy controls and the ataxic patients. Among the earliest functional deficits in SCA6 are eye movement abnormalities, including impaired saccade velocity, saccade metrics, and pursuit gain. This suggests that early functional impairments are caused by cellular dysfunction and/or loss in the posterior cerebellar vermis and flocculus. These findings might help to determine the timing of a treatment and to define variables that could be used as outcome measures for the efficacy of therapeutic trials.

Evidence of Impaired Proprioception in Chronic, Idiopathic Neck Pain: Systematic Review and Meta-Analysis

PubMed Central

Leake, Hayley B.; Chalmers, K. Jane; Moseley, G. Lorimer

2016-01-01

Background Despite common use of proprioceptive retraining interventions in people with chronic, idiopathic neck pain, evidence that proprioceptive dysfunction exists in this population is lacking. Determining whether proprioceptive dysfunction exists in people with chronic neck pain has clear implications for treatment prescription. Purpose The aim of this study was to synthesize and critically appraise all evidence evaluating proprioceptive dysfunction in people with chronic, idiopathic neck pain by completing a systematic review and meta-analysis. Data Sources MEDLINE, CINAHL, PubMed, Allied and Complementary Medicine, EMBASE, Academic Search Premier, Scopus, Physiotherapy Evidence Database (PEDro), and Cochrane Collaboration databases were searched. Study Selection All published studies that compared neck proprioception (joint position sense) between a chronic, idiopathic neck pain sample and asymptomatic controls were included. Data Extraction Two independent reviewers extracted relevant population and proprioception data and assessed methodological quality using a modified Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement. Data Synthesis Thirteen studies were included in the present review. Meta-analysis on 10 studies demonstrated that people with chronic neck pain perform significantly worse on head-to-neutral repositioning tests, with a moderate standardized mean difference of 0.44 (95% confidence interval=0.25, 0.63). Two studies evaluated head repositioning using trunk movement (no active head movement thus hypothesized to remove vestibular input) and showed conflicting results. Three studies evaluated complex or postural repositioning tests; postural repositioning was no different between groups, and complex movement tests were impaired only in participants with chronic neck pain if error was continuously evaluated throughout the movement. Limitations A paucity of studies evaluating complex or postural repositioning tests does not permit any solid conclusions about them. Conclusions People with chronic, idiopathic neck pain are worse than asymptomatic controls at head-to-neutral repositioning tests. PMID:26472296

Effects of Peripheral Vestibular Dysfunction on Dynamic Postural Stability Measured by the Functional Reach Test and Timed Up and Go Test.

PubMed

Nishi, Toshiko; Kamogashira, Teru; Fujimoto, Chisato; Kinoshita, Makoto; Egami, Naoya; Sugasawa, Keiko; Yamasoba, Tatsuya; Iwasaki, Shinichi

2017-06-01

To investigate the influence of vestibular function on dynamic postural stability assessed by the functional reach test (FRT) and the timed up and go test (TUG). Retrospective study. Tertiary referral center. The FRT and TUG were performed in 399 patients with dizziness. The effects of peripheral vestibular dysfunction assessed by the caloric test and cervical vestibular evoked myogenic potentials (cVEMPs) to air-conducted sound (500 Hz, tone burst) on the results of FRT and TUG were analyzed. Neither FRT nor TUG scores showed significant differences in relation to the results of the caloric test ( P > .3). The FRT scores in patients who showed abnormal cVEMP responses on both sides were significantly smaller than those in patients who showed normal cVEMP responses ( P < .01). The TUG scores in patients who showed abnormal cVEMP responses on both sides were significantly greater than those in patients who showed normal cVEMP responses ( P < .05). The vestibulo-spinal reflex mediated by the saccule and its afferents is one of the factors that influence the maintenance of dynamic postural stability as measured by FRT and TUG.

Neuromagnetic brain activity associated with anticipatory postural adjustments for bimanual load lifting.

PubMed

Ng, Tommy H B; Sowman, Paul F; Brock, Jon; Johnson, Blake W

2013-02-01

During bimanual load lifting, the brain must anticipate the effects of unloading upon the load-bearing arm. Little is currently known about the neural networks that coordinate these anticipatory postural adjustments. We measured neuromagnetic brain activity with whole-head magnetoencephalography while participants performed a bimanual load-lifting task. Anticipatory adjustments were associated with reduction in biceps brachii muscle activity of the load-bearing arm and pre-movement desynchronization of the cortical beta rhythm. Beamforming analyses localized anticipatory brain activity to the precentral gyrus, basal ganglia, supplementary motor area, and thalamus, contralateral to the load-bearing arm. To our knowledge this is the first human neuroimaging study to directly investigate anticipatory postural adjustments and to explicitly partition the anticipatory and volitional aspects of brain activity in bimanual load lifting. These data contribute to our understanding of the neural systems supporting anticipatory postural adjustments in healthy adults. Copyright © 2012 Elsevier Inc. All rights reserved.

Postural balance and the risk of falling during pregnancy.

PubMed

Cakmak, Bulent; Ribeiro, Ana Paula; Inanir, Ahmet

2016-01-01

Pregnancy is a physiological process and many changes occur in a woman's body during pregnancy. These changes occur in all systems to varying degrees, including the cardiovascular, respiratory, genitourinary, and musculoskeletal systems. The hormonal, anatomical, and physiological changes occurring during pregnancy result in weight gain, decreased abdominal muscle strength and neuromuscular control, increased ligamentous laxity, and spinal lordosis. These alterations shift the centre of gravity of the body, altering the postural balance and increasing the risk of falls. Falls during pregnancy can cause maternal and foetal complications, such as maternal bone fractures, head injuries, internal haemorrhage, abruption placenta, rupture of the uterus and membranes, and occasionally maternal death or intrauterine foetal demise. Preventative strategies, such as physical exercise and the use of maternity support belts, can increase postural stability and reduce the risk of falls during pregnancy. This article reviews studies that have investigated changes in postural balance and risk of falling during pregnancy.

Cervicocephalic kinesthetic sensibility and postural balance in patients with nontraumatic chronic neck pain – a pilot study

PubMed Central

Palmgren, Per J; Andreasson, Daniel; Eriksson, Magnus; Hägglund, Andreas

2009-01-01

Background Although cervical pain is widespread, most victims are only mildly and occasionally affected. A minority, however, suffer chronic pain and/or functional impairments. Although there is abundant literature regarding nontraumatic neck pain, little focuses on diagnostic criteria. During the last decade, research on neck pain has been designed to evaluate underlying pathophysiological mechanisms, without noteworthy success. Independent researchers have investigated postural balance and cervicocephalic kinesthetic sensibility among patients with chronic neck pain, and have (in most cases) concluded the source of the problem is a reduced ability in the neck's proprioceptive system. Here, we investigated cervicocephalic kinesthetic sensibility and postural balance among patients with nontraumatic chronic neck pain. Methods Ours was a two-group, observational pilot study of patients with complaints of continuous neck pain during the 3 months prior to recruitment. Thirteen patients with chronic neck pain of nontraumatic origin were recruited from an institutional outpatient clinic. Sixteen healthy persons were recruited as a control group. Cervicocephalic kinesthetic sensibility was assessed by exploring head repositioning accuracy and postural balance was measured with computerized static posturography. Results Parameters of cervicocephalic kinesthetic sensibility were not reduced. However, in one of six test movements (flexion), global repositioning errors were significantly larger in the experimental group than in the control group (p < .05). Measurements did not demonstrate any general impaired postural balance, and varied substantially among participants in both groups. Conclusion In patients with nontraumatic chronic neck pain, we found statistically significant global repositioning errors in only one of six test movements. In this cohort, we found no evidence of impaired postural balance. Head repositioning accuracy and computerized static posturography are imperfect measures of functional proprioceptive impairments. Validity of (and procedures for using) these instruments demand further investigation. Trial registration Current Controlled Trials ISRCTN96873990 PMID:19566929

Methomyl poisoning presenting with decorticate posture and cortical blindness.

PubMed

Lin, Chih-Ming

2014-01-17

Methomyl is a potent pesticide that is widely used in the field of agriculture. The systemic toxic effects of methomyl have been well described. However, the neurological effects of methomyl intoxication are not well understood. In this study, we report a 61-year-old Taiwanese man sent to our emergency department because of altered mental status. His family stated that he had consumed liquid methomyl in a suicide attempt. He was provided cardiopulmonary resuscitation because of unstable vital signs. He was then sent to an intensive care unit for close observation. On the second day of admission, he regained consciousness but exhibited irregular limb and torso posture. On the sixth day, he started to complain of blurred vision. An ophthalmologist was consulted but no obvious abnormalities could be identified. On suspicion of cerebral disease, a neurologist was consulted. Further examination revealed cortical blindness and decorticate posture. Cerebral magnetic resonance imaging (MRI) was arranged, which identified bilateral occipital regions lesions. The patient was administered normal saline and treated with aspirin and piracetam for 3 weeks in hospital. During the treatment period, his symptom of cortical blindness resolved, whereas his decorticate posture was refractory. Follow-up brain MRI results supported our clinical observations by indicating the disappearance of the bilateral occipital lesions and symmetrical putaminal high signal abnormalities. In this article, we briefly discuss the possible mechanisms underlying the cerebral effects of methomyl poisoning. Our study can provide clinicians with information on the manifestations of methomyl intoxication and an appropriate treatment direction.

M.I.T./Canadian vestibular experiments on the Spacelab-1 mission. I - Sensory adaptation to weightlessness and readaptation to one-g: An overview

NASA Technical Reports Server (NTRS)

Young, L. R.; Oman, C. M.; Lichtenberg, B. K.; Watt, D. G. D.; Money, K. E.

1986-01-01

Human sensory/motor adaptation to weightlessness and readaptation to earth's gravity are assessed. Preflight and postflight vestibular and visual responses for the crew on the Spacelab-1 mission are studied; the effect of the abnormal pattern of otolith afferent signals caused by weightlessness on the pitch and roll perception and postural adjustments of the subjects are examined. It is observed that body position and postural reactions change due to weightlessness in order to utilize the varied sensory inputs in a manner suited to microgravity conditions. The aspects of reinterpretation include: (1) tilt acceleration reinterpretation, (2) reduced postural response to z-axis linear acceleration, and (3) increased attention to visual cues.

Embodying animals: Body-part compatibility in mammalian, reptile and aves classes.

PubMed

Pacione, Sandra M; Welsh, Timothy N

2015-09-01

The purpose of the present study was to determine how humans code homologous body parts of nonhuman mammal, reptilian, and aves animals with respect to the representation of the human body. To this end, participants completed body-part compatibility tasks in which responses were executed to colored targets that were superimposed over the upper limbs, lower limbs or head of different animals in different postures. In Experiment 1, the images were of meekats and lizards in bipedal and quadrupedal postures. In Experiment 2, the images were of a human, a penguin, and an owl in a bipedal posture with upper limbs stretched out. Overall, the results revealed that the limbs of nonhuman mammals (meerkat and human) were consistently mapped onto the homologous human body parts only when the mammals were in a bipedal posture. Specifically, body-part compatibility effects emerged for the human and the meerkat in a bipedal posture, but not the meerkat in the quadrupedal posture. Further, consistent body-part compatibility effects were not observed for the lizard in the quadrupedal posture or for the lizard, penguin, or owl in a bipedal posture. The pattern of results suggests that the human bipedal body representation may distinguish taxonomical classes and is most highly engaged when viewing homologous body parts of mammalian animals. Copyright © 2015 Elsevier B.V. All rights reserved.

Local fluid shifts and edema in humans during simulated microgravity

NASA Technical Reports Server (NTRS)

Hargens, Alan R.

1991-01-01

Local fluid shifts and edema in humans during simulated microgravity is studied. Recent results and significance and future plans on the following research topics are discussed: mechanisms of headward edema formation during head-down tilt; postural responses of head and foot microcirculations and their sensitivity to bed rest; and transcapillary fluid transport associated with lower body negative pressure (LBNP) with and without saline ingestion.

Evidence for a general stiffening motor control pattern in neck pain: a cross sectional study.

PubMed

Meisingset, Ingebrigt; Woodhouse, Astrid; Stensdotter, Ann-Katrin; Stavdahl, Øyvind; Lorås, Håvard; Gismervik, Sigmund; Andresen, Hege; Austreim, Kristian; Vasseljen, Ottar

2015-03-17

Neck pain is associated with several alterations in neck motion and motor control. Previous studies have investigated single constructs of neck motor control, while few have applied a comprehensive set of tests to investigate cervical motor control. This comparative cross- sectional study aimed to investigate different motor control constructs in neck pain patients and healthy controls. A total of 166 subjects participated in the study, 91 healthy controls (HC) and 75 neck pain patients (NP) with long-lasting moderate to severe neck pain. Neck flexibility, proprioception, head steadiness, trajectory movement control, and postural sway were assessed using a 3D motion tracking system (Liberty). The different constructs of neck motion and motor control were based on tests used in previous studies. Neck flexibility was lower in NP compared to HC, indicated by reduced cervical ROM and conjunct motion. Movement velocity was slower in NP compared to HC. Tests of head steadiness showed a stiffer movement pattern in NP compared to HC, indicated by lower head angular velocity. NP patients departed less from a predictable trajectory movement pattern (figure of eight) compared to healthy controls, but there was no difference for unpredictable movement patterns (the Fly test). No differences were found for postural sway in standing with eyes open and eyes closed. However, NP patients had significantly larger postural sway when standing on a balance pad. Proprioception did not differ between the groups. Largest effect sizes (ES) were found for neck flexibility (ES range: 0.2-0.8) and head steadiness (ES range: 1.3-2.0). Neck flexibility was the only construct that showed a significant association with current neck pain, while peak velocity was the only variable that showed a significant association with kinesiophobia. NP patients showed an overall stiffer and more rigid neck motor control pattern compared to HC, indicated by lower neck flexibility, slower movement velocity, increased head steadiness and more rigid trajectory head motion patterns. Only neck flexibility showed a significant association with clinical features in NP patients.

Acute Cutaneous Microvascular Flow Responses to Whole-Body Tilting in Humans

NASA Technical Reports Server (NTRS)

Breit, Gregory A.; Watenpaugh, Donald E.; Ballard, Richard E.; Hargens, Alan R.

1993-01-01

The transition from upright to head-down tilt (HDT) posture in humans increases blood pressure superior to the heart and decreases pressure inferior to the heart. Consequently, above heart level, myogenic arteriolar tone probably increases with HDT, in opposition to the withdrawal of baroreceptor-mediated sympathetic tone. We hypothesized that due to antagonism between central and local controls, the response of the facial cutaneous micro- circulation to acute postural change will be weaker than that in the leg, where these two mechanisms reinforce each other. Cutaneous microvascular flow was measured by laser Doppler flowmetry simultaneously at the shin and the neck of 7 male and 3 female subjects. Subjects underwent a stepwise tilt protocol from standing control to 54 deg head-up tilt (HUT), 30 deg, 12 deg, 0 deg, -6 deg (HDT), -12 deg, -6 deg, 0 deg, 12 deg, 30 deg, 54 deg, and standing, for 30-sec periods with 10-sec transitions between postures. Flows at the shin and the neck increased significantly (P < 0.05) from standing baseline to 12 deg HUT (252 +/- 55 and 126 +/- 9% (bar-X +/- SE) of baseline, respectively). From 12 deg to -12 deg tilt, flows continued to increase at the shin (509 +/- 71% of baseline) but decreased at the neck to baseline levels (100 +/- 15% of baseline). Cutaneous microvascular flow recovered at both sites during the return to standing posture with significant hysteresis. Flow increases from standing to near-supine posture are attributed at both sites to baroreceptor-mediated vasodilation. The great dissimilarity in flow response magnitudes at the two measurement sites may be indicative of central/local regulatory antagonism above heart level and reinforcement below heart level.

Acute Cutaneous Microvascular Flow Responses to Whole-Body Tilting in Humans

NASA Technical Reports Server (NTRS)

Breit, Gregory A.; Watenpaugh, Donald E.; Ballard, Richard E.; Hargens, Alan R.

1993-01-01

The transition from upright to head-down tilt (HDT) posture in humans increases blood pressure superior to the heart and decreases pressure inferior to the heart. Consequently, above heart level, myogenic arteriolar tone probably increases with HDT, in opposition to the withdrawal of baroreceptor-mediated sympathetic tone. We hypothesized that due to antagonism between central and local controls, the response of the facial cutaneous microcirculation to acute postural change will be weaker than that in the leg, where these two mechanisms reinforce each other. Cutaneous microvascular flow was measured by laser Doppler flowmetry simultaneously at the shin and the neck of 7 male and 3 female subjects. Subjects underwent a stepwise tilt protocol from standing control to 54 deg head-up tilt (HUT), 30 deg, 12 deg, O deg, -6 deg (HDT), -12 deg, -6 deg, O deg, 12 deg, 30 deg, 54 deg, and standing, for 30-sec periods with 10-sec transitions between postures. Flows at the shin and the neck increased significantly (P less than 0.05) from standing baseline to 12 deg HUT (252 +/- 55 and 126 +/- 9% (bar X +/- SE) of baseline, respectively). From 12 deg to -12 deg tilt, flows continued to increase at the shin (509 +/- 71% of baseline) but decreased at the neck to baseline levels (100 +/- 15% of baseline). Cutaneous microvascular flow recovered at both sites during the return to standing posture with significant hysteresis. Flow increases from standing to near-supine posture are attributed at both sites to baroreceptor-mediated vasodilation. The great dissimilarity in flow response magnitudes at the two measurement sites may be indicative of central/local regulatory antagonism above heart level and reinforcement below heart level.

An analysis of the activity and muscle fatigue of the muscles around the neck under the three most frequent postures while using a smartphone

PubMed Central

Choi, Jung-Hyun; Jung, Min-Ho; Yoo, Kyung-Tae

2016-01-01

[Purpose] The purpose of this study was to identify changes in the activity and fatigue of the splenius capitis and upper trapezius muscles, which are agonists to the muscles supporting the head, under the three postures most frequently adopted while using a smartphone. [Subjects and Methods] The subjects were 15 college students in their 20s. They formed a single group and had to adopt three different postures (maximum bending, middle bending, and neutral). While the 15 subjects maintained the postures, muscle activity and fatigue were measured using surface electromyography. [Results] Comparison of the muscle fatigue caused by each posture showed statistically significant differences for the right splenius capitis, left splenius capitis, and left upper trapezius muscles. In addition, maintaining the maximum bending posture while using a smartphone resulted in higher levels of fatigue in the right splenius capitis, left splenius capitis, and left upper trapezius muscles compared with those for the middle bending posture. [Conclusion] Therefore, this study suggests that individuals should bend their neck slightly when using a smartphone, rather than bending it too much, or keep their neck straight to reduce fatigue of the cervical erector muscles. PMID:27313393

Motion analysis in the field of dentistry: a kinematic comparison of dentists and orthodontists

PubMed Central

Nowak, J; Erbe, C; Hauck, I; Groneberg, D A; Hermanns, I; Ellegast, R; Ditchen, D; Ohlendorf, D

2016-01-01

Objectives To conduct a kinematic comparison of occupational posture in orthodontists and dentists in their workplace. Design Observational study. Setting Dentist surgeries and departments of orthodontics at university medical centres in Germany. Participants A representative sample of 21 (10 female, 11 male) dentists (group G1) and 21 (13 female, 8 male) orthodontists (G2) with one male dropout in G2. Outcome measures The CUELA (computer-assisted acquisition and long-term analysis of musculoskeletal loads) system was used to analyse occupational posture. Parallel to the recording through the CUELA system, a software-supported analysis of the activities performed (I: treatment; II: office; III: other activities) was carried out. In line with ergonomic standards the measured body angles are categorised into neutral, moderate and awkward postures. Activities between the aforementioned groups are compared using the stratified van Elteren U test and the Wilcoxon–Mann–Whitney U test. All p values are subject to the Bonferroni–Holm correction. The level of significance is set at 5%. Results The percentage of time spent on activities in categories I–II–III was as follows: dentists 41%–23%–36% and orthodontists 28%–37%–35%. The posture analysis of both groups showed, for all percentiles (P5–95), angle values primarily in the neutral or moderate range. However, depending on the activity performed, between 5% and 25% of working hours were spent in unfavourable postures, especially in the head-and-neck area. Orthodontists have a greater tendency than dentists to perform treatment activities with the head and torso in unfavourable positions. The statistically significant differences between the two groups with regard to the duration and the relevance of the activities performed confirm this assumption for all three categories (p<0.01, p<0.05). Conclusions Generally, both groups perform treatment activities in postures that are in the neutral or medium range; however, dentists had slightly more unfavourable postures during treatment for a greater share of their work day. PMID:27531728

Motion analysis in the field of dentistry: a kinematic comparison of dentists and orthodontists.

PubMed

Nowak, J; Erbe, C; Hauck, I; Groneberg, D A; Hermanns, I; Ellegast, R; Ditchen, D; Ohlendorf, D

2016-08-16

To conduct a kinematic comparison of occupational posture in orthodontists and dentists in their workplace. Observational study. Dentist surgeries and departments of orthodontics at university medical centres in Germany. A representative sample of 21 (10 female, 11 male) dentists (group G1) and 21 (13 female, 8 male) orthodontists (G2) with one male dropout in G2. The CUELA (computer-assisted acquisition and long-term analysis of musculoskeletal loads) system was used to analyse occupational posture. Parallel to the recording through the CUELA system, a software-supported analysis of the activities performed (I: treatment; II: office; III: other activities) was carried out. In line with ergonomic standards the measured body angles are categorised into neutral, moderate and awkward postures. Activities between the aforementioned groups are compared using the stratified van Elteren U test and the Wilcoxon-Mann-Whitney U test. All p values are subject to the Bonferroni-Holm correction. The level of significance is set at 5%. The percentage of time spent on activities in categories I-II-III was as follows: dentists 41%-23%-36% and orthodontists 28%-37%-35%. The posture analysis of both groups showed, for all percentiles (P5-95), angle values primarily in the neutral or moderate range. However, depending on the activity performed, between 5% and 25% of working hours were spent in unfavourable postures, especially in the head-and-neck area. Orthodontists have a greater tendency than dentists to perform treatment activities with the head and torso in unfavourable positions. The statistically significant differences between the two groups with regard to the duration and the relevance of the activities performed confirm this assumption for all three categories (p<0.01, p<0.05). Generally, both groups perform treatment activities in postures that are in the neutral or medium range; however, dentists had slightly more unfavourable postures during treatment for a greater share of their work day. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

An evaluation of 3D head pose estimation using the Microsoft Kinect v2.

PubMed

Darby, John; Sánchez, María B; Butler, Penelope B; Loram, Ian D

2016-07-01

The Kinect v2 sensor supports real-time non-invasive 3D head pose estimation. Because the sensor is small, widely available and relatively cheap it has great potential as a tool for groups interested in measuring head posture. In this paper we compare the Kinect's head pose estimates with a marker-based record of ground truth in order to establish its accuracy. During movement of the head and neck alone (with static torso), we find average errors in absolute yaw, pitch and roll angles of 2.0±1.2°, 7.3±3.2° and 2.6±0.7°, and in rotations relative to the rest pose of 1.4±0.5°, 2.1±0.4° and 2.0±0.8°. Larger head rotations where it becomes difficult to see facial features can cause estimation to fail (10.2±6.1% of all poses in our static torso range of motion tests) but we found no significant changes in performance with the participant standing further away from Kinect - additionally enabling full-body pose estimation - or without performing face shape calibration, something which is not always possible for younger or disabled participants. Where facial features remain visible, the sensor has applications in the non-invasive assessment of postural control, e.g. during a programme of physical therapy. In particular, a multi-Kinect setup covering the full range of head (and body) movement would appear to be a promising way forward. Copyright © 2016 Elsevier B.V. All rights reserved.

Head sway response to optic flow: effect of age is more important than the presence of unilateral vestibular hypofunction

PubMed Central

Sparto, Patrick J.; Furman, Joseph M.; Redfern, Mark S.

2014-01-01

Background The purpose of this study was to examine how older adults with vestibular impairment use sensory feedback for postural control. Methods Nine older adult subjects with unilateral vestibular hypofunction (UVH, mean age 69 y) and 14 older (mean age 70 y) and 8 young adult controls (CON, mean age 28 y) viewed full-field optic flow scenes while standing on a fixed or sway-referenced support surface. The subjects with UVH had 100% caloric asymmetry. Optic flow consisted of sinusoidal anterior-posterior movement of the visual surround at three frequencies and three amplitudes of stimulation. The anterior-posterior head sway was measured. The number of head sway responses that were coupled to the optic flow and magnitude of head sway during optic flow relative to during quiet stance on fixed floor was quantified. Results The number of trials in which the head sway response was significantly coupled to the optic flow was significantly greater in the Older UVH and Older CON subjects compared with the Young CON subjects. Furthermore, the magnitude of head sway was two to three times greater in Older UVH and CON compared with Young CON subjects. There was no difference in coupling or magnitude of head sway between Older UVH and Older CON subjects. The amplitude of sway was also dependent on the amount of surface support, stimulus frequency, and stimulus amplitude. Conclusions Older adults with unilateral vestibular hypofunction who are able to effectively compensate show no difference in postural responses elicited by optic flow compared with age-matched controls. PMID:17312341

Prospective study of swallowing function in patients with cervical dystonia undergoing selective peripheral denervation

PubMed Central

Munchau, A; Good, C; McGowan, S; Quinn, N; Palmer, J; Bhatia, K

2001-01-01

OBJECTIVE—To characterise swallowing function in patients with cervical dystonia with botulinum toxin treatment failure, before and after selective peripheral denervation surgery.
METHODS—Twelve patients with cervical dystonia had a thorough examination including standardised assessment for cervical dystonia, scoring of subjective dysphagia, and videofluoroscopic swallow. Videofluoroscopy was scored by consensus opinion between a speech and language therapist and an independent blinded radiologist using a validated scoring system.
RESULTS—Seven patients with cervical dystonia experienced no subjective dysphagia either before or after surgery, although in all these patients there was objective videofluoroscopic evidence of underlying mild to moderate oropharyngeal dysphagia preoperatively and postoperatively. The most common finding was delayed initiation of swallow. Three other patients, also without subjective dysphagia before surgery, developed postoperative dysphagia. In these patients, videofluoroscopy showed a delayed swallow reflex before surgery, which was worse postoperatively in two. The remaining two patients had mild subjective dysphagia before surgery that improved postoperatively in one and deteriorated in the other. In the first, videofluoroscopy was normal preoperatively and postoperatively, and in the second, oral bolus preparation was moderately abnormal preoperatively and swallow initiation was delayed postoperatively. Mean subjective dysphagia scores did not change significantly. Apart from a significant improvement of tongue base retraction, videofluoroscopic scores were not significantly different after surgery. Postoperatively there was significant improvement of overall cervical dystonia severity and abnormal head rotation in the group as a whole. There was no correlation between age, duration of symptoms of cervical dystonia, preoperative or postoperative cervical dystonia severity, subjective dysphagia scores, or videofluoroscopic scores. However, in the five patients with persisting anterior sagittal head shift as part of the torticollis, tongue base retraction was less likely to improve after surgery compared with those without head shift.
CONCLUSION—Surgical denervation of dystonic neck muscles, leading to improved neck posture, can also improve tongue base retraction, which is a key component of normal bolus propagation. However, delayed swallow initiation, a common feature in patients with cervical dystonia, can be further compromised by surgery, leading to subjective dysphagia. In general, selective peripheral denervation seems to be a safe procedure with no major compromise of swallowing function.

 PMID:11413266

Postural asymmetries in young adults with cerebral palsy.

PubMed

Rodby-Bousquet, Elisabet; Czuba, Tomasz; Hägglund, Gunnar; Westbom, Lena

2013-11-01

The purpose was to describe posture, ability to change position, and association between posture and contractures, hip dislocation, scoliosis, and pain in young adults with cerebral palsy (CP). Cross-sectional data of 102 people (63 males, 39 females; age range 19-23 y, median 21 y) out of a total population with CP was analysed in relation to Gross Motor Function Classification System (GMFCS) levels I (n=38), II (n=21), III (n=13), IV (n=10), and V (n=20). The CP subtypes were unilateral spastic (n=26), bilateral spastic (n=45), ataxic (n=12), and dyskinetic CP (n=19). The Postural Ability Scale was used to assess posture. The relationship between posture and joint range of motion, hip dislocation, scoliosis, and pain was analysed using logistic regression and Spearman's correlation. At GMFCS levels I to II, head and trunk asymmetries were most common; at GMFCS levels III to V postural asymmetries varied with position. The odds ratios (OR) for severe postural asymmetries were significantly higher for those with scoliosis (OR=33 sitting), limited hip extension (OR=39 supine), or limited knee extension (OR=37 standing). Postural asymmetries correlated to hip dislocations: supine (r(s) =0.48), sitting (r(s) =0.40), standing (r(s) =0.41), and inability to change position: supine (r(s) =0.60), sitting (r(s) =0.73), and standing (r(s) =0.64). Postural asymmetries were associated with scoliosis, hip dislocations, hip and knee contractures, and inability to change position. © 2013 The Authors. Developmental Medicine & Child Neurology published by John Wiley & Sons Ltd on behalf of Mac Keith Press.

Postural asymmetries in young adults with cerebral palsy

PubMed Central

Rodby-Bousquet, Elisabet; Czuba, Tomasz; Hägglund, Gunnar; Westbom, Lena

2013-01-01

Aim The purpose was to describe posture, ability to change position, and association between posture and contractures, hip dislocation, scoliosis, and pain in young adults with cerebral palsy (CP). Methods Cross-sectional data of 102 people (63 males, 39 females; age range 19–23y, median 21y) out of a total population with CP was analysed in relation to Gross Motor Function Classification System (GMFCS) levels I (n=38), II (n=21), III (n=13), IV (n=10), and V (n=20). The CP subtypes were unilateral spastic (n=26), bilateral spastic (n=45), ataxic (n=12), and dyskinetic CP (n=19). The Postural Ability Scale was used to assess posture. The relationship between posture and joint range of motion, hip dislocation, scoliosis, and pain was analysed using logistic regression and Spearman’s correlation. Results At GMFCS levels I to II, head and trunk asymmetries were most common; at GMFCS levels III to V postural asymmetries varied with position. The odds ratios (OR) for severe postural asymmetries were significantly higher for those with scoliosis (OR=33 sitting), limited hip extension (OR=39 supine), or limited knee extension (OR=37 standing). Postural asymmetries correlated to hip dislocations: supine (rs=0.48), sitting (rs=0.40), standing (rs=0.41), and inability to change position: supine (rs=0.60), sitting (rs=0.73), and standing (rs=0.64). Conclusions Postural asymmetries were associated with scoliosis, hip dislocations, hip and knee contractures, and inability to change position. This article is commented on by Novak on page 974 of this issue. PMID:23834239

Cervical column posture and airway dimensions in clinical bruxist adults: a preliminary study.

PubMed

Restrepo, C C; Álvarez, C P; Jaimes, J; Gómez, A F

2013-11-01

The aim of this study was to compare the cervical column posture and the upper airway dimensions between sleep bruxist and non-bruxist young adults. Twenty-three sleep-grinders and 22 asymptomatic subjects, selected according to the American Academy of Sleep Medicine (AASM) criteria (report by a sleep partner and the presence of dental wear, according to Wetselaar et al.), were evaluated. The mean age was 23·8 years (range 18-30). All the subjects had complete permanent dentition and skeletal and occlusal class I. A digital cephalometric radiograph with natural head posture was performed for each subject. The craniocervical posture was traced and evaluated according to Solow and Tallgren, and the airway dimensions of the oropharynx and nasopharynx were evaluated in agreement with Sayinsu. The data were analysed with independent-samples t-tests and Mann-Whitney U-test. Significance was set at P < 0·05. Sleep bruxist young adults presented more forwarded cervical column posture and narrower measures of the oropharynx, when compared with controls (P < 0·05). As in children, anterior cervical column posture was found to be associated with sleep bruxism. © 2013 John Wiley & Sons Ltd.

Development of a Wearable Instrumented Vest for Posture Monitoring and System Usability Verification Based on the Technology Acceptance Model.

PubMed

Lin, Wen-Yen; Chou, Wen-Cheng; Tsai, Tsai-Hsuan; Lin, Chung-Chih; Lee, Ming-Yih

2016-12-17

Body posture and activity are important indices for assessing health and quality of life, especially for elderly people. Therefore, an easily wearable device or instrumented garment would be valuable for monitoring elderly people's postures and activities to facilitate healthy aging. In particular, such devices should be accepted by elderly people so that they are willing to wear it all the time. This paper presents the design and development of a novel, textile-based, intelligent wearable vest for real-time posture monitoring and emergency warnings. The vest provides a highly portable and low-cost solution that can be used both indoors and outdoors in order to provide long-term care at home, including health promotion, healthy aging assessments, and health abnormality alerts. The usability of the system was verified using a technology acceptance model-based study of 50 elderly people. The results indicated that although elderly people are anxious about some newly developed wearable technologies, they look forward to wearing this instrumented posture-monitoring vest in the future.

Development of a Wearable Instrumented Vest for Posture Monitoring and System Usability Verification Based on the Technology Acceptance Model

PubMed Central

Lin, Wen-Yen; Chou, Wen-Cheng; Tsai, Tsai-Hsuan; Lin, Chung-Chih; Lee, Ming-Yih

2016-01-01

Body posture and activity are important indices for assessing health and quality of life, especially for elderly people. Therefore, an easily wearable device or instrumented garment would be valuable for monitoring elderly people’s postures and activities to facilitate healthy aging. In particular, such devices should be accepted by elderly people so that they are willing to wear it all the time. This paper presents the design and development of a novel, textile-based, intelligent wearable vest for real-time posture monitoring and emergency warnings. The vest provides a highly portable and low-cost solution that can be used both indoors and outdoors in order to provide long-term care at home, including health promotion, healthy aging assessments, and health abnormality alerts. The usability of the system was verified using a technology acceptance model-based study of 50 elderly people. The results indicated that although elderly people are anxious about some newly developed wearable technologies, they look forward to wearing this instrumented posture-monitoring vest in the future. PMID:27999324

Postural Effects on Intracranial Pressure as Assessed Noninvasively

NASA Technical Reports Server (NTRS)

Ueno, Toshiaki; Hargens, Alan R.; Ballard, R. E.; Shuer, L. M.; Cantrell, J. H.; Yost, W. T.; Holton, Emily M. (Technical Monitor)

1997-01-01

This study was designed to investigate effects of whole body tilting on intracranial compliance and pressure in six healthy volunteers by using a noninvasive ultrasonic device. Subjects were randomly tilted up or down sequentially at 60 degree, 30 degree head-up, supine, and 15 degree head-down position for one minute at each angle. We measured arterial blood pressure with a finger pressure cuff and changes in intracranial distance with an ultrasonic device. The device measures skull movement on the order of micro-meter. Our ultrasound technique demonstrates that skull movement is highly correlated (r$(circumflex){2}$=0.77) with intracranial pressure variations due to cerebral arterial pulsation. The amplitudes of arterial pressure (r$(circumflex){2}$=0.99 and those of intracranial distance changes (r$(circumflex){2}$=0.87) associated with one cardiac cycle were inversely correlated with the angle of tilt. The ratio of pulsation amplitudes for intracranial distance over arterial pressure also showed a significant increase as the angle of tilt was lowered (p=0.003). Thus, postural changes alter intracranial compliance in healthy volunteers and intracranial volume-buffering capacity is reduced in head-down position.

Inertial vestibular coding of motion: concepts and evidence

NASA Technical Reports Server (NTRS)

Hess, B. J.; Angelaki, D. E.

1997-01-01

Central processing of inertial sensory information about head attitude and motion in space is crucial for motor control. Vestibular signals are coded relative to a non-inertial system, the head, that is virtually continuously in motion. Evidence for transformation of vestibular signals from head-fixed sensory coordinates to gravity-centered coordinates have been provided by studies of the vestibulo-ocular reflex. The underlying central processing depends on otolith afferent information that needs to be resolved in terms of head translation related inertial forces and head attitude dependent pull of gravity. Theoretical solutions have been suggested, but experimental evidence is still scarce. It appears, along these lines, that gaze control systems are intimately linked to motor control of head attitude and posture.

Modeling length-tension properties of RCPm muscles during voluntary retraction of the head.

PubMed

Hallgren, Richard C

2014-08-01

Head retraction exercises are one of several commonly used clinical tools that are used to assess and treat patients with head and neck pain and to aid in restoration of a normal neutral head posture. Retraction of the head results in flexion of the occipitoatlantal (OA) joint and stretching of rectus capitis posterior minor (RCPm) muscles. The role that retraction of the head might have in treating head and neck pain patients is currently unknown. RCPm muscles arise from the posterior tubercle of the posterior arch of C1 and insert into the occipital bone inferior to the inferior nuchal line and lateral to the midline. RCPm muscles are the only muscles that attach to the posterior arch of C1. The functional role of RCPm muscles has not been clearly defined. The goal of this project was to develop a three-dimensional, computer-based biomechanical model of the posterior aspect of the OA joint. This model should help clarify why voluntary head retraction exercises seem to contribute to the resolution of head and neck pain and restoration of a normal head posture in some patients. The model documents that length-tension properties of RCPm muscles are significantly affected by variations in the physical properties of the musculotendonous unit. The model suggests that variations in the cross sectional area of RCPm muscles due to pathologies that weaken the muscle, such as muscle atrophy, may reduce the ability of these muscles to generate levels of force that are necessary for the performance of normal, daily activities. The model suggests that the main benefit of the initial phase of head retraction exercises may be to strengthen RCPm muscles through eccentric contractions, and that the main benefit of the final phase of retraction may be to stretch the muscles as the final position is held. Copyright © 2014 Elsevier Ltd. All rights reserved.

Investigation of associations between recurrence of major depressive disorder and spinal posture alignment: A quantitative cross-sectional study.

PubMed

Canales, Janette Z; Fiquer, Juliana T; Campos, Rodolfo N; Soeiro-de-Souza, Márcio Gerhardt; Moreno, Ricardo Alberto

2017-02-01

The aim of this study was to investigate associations between poor spinal posture and the recurrence of major depressive episodes and severity of symptoms in patients with major depressive disorder (MDD). This was a cross-sectional quantitative study of MDD patients. Outpatients were recruited from consecutive admissions at a mood disorders unit of a tertiary psychiatric hospital. Of 136 MDD patients, 72 (53 women, 19 men; mean age, 42.4±9.1years) met all the criteria and completed the study. Forty-one patients were classified with a recurrent episode (RE) of MDD and 31 with a single episode (SE). Quantitative assessments of postural deviations were made using photogrammetry, including kyphosis, shoulder protraction, and head inclination. The severity of depressive episodes was assessed using the Hamilton Depression Rating Scale. The diagnosis and classification of patients were performed according to DSM-IV-TR and SCID criteria. Multivariate analysis of variance indicated that the RE group had greater anterior head inclination (35.39; SD: 1.57), greater scapular abduction (1.69; SD: 0.93), and worse thoracic kyphosis (139.38; SD: 1.19) than the SE group (p<0.001 for all). Multivariate analysis of covariance showed an interaction between the severity of depressive symptoms and the degree of thoracic kyphosis (p=0.002). Recurrence of depressive episodes is associated with measures of postural misalignment. Copyright © 2016 Elsevier B.V. All rights reserved.

Healthy Active Duty Military with Lifetime Experience of Mild Traumatic Brain Injury Exhibits Subtle Deficits in Sensory Reactivity and Sensory Integration During Static Balance.

PubMed

Wright, W Geoffrey; Handy, Justin D; Avcu, Pelin; Ortiz, Alejandro; Haran, F Jay; Doria, Michael; Servatius, Richard J

2018-03-01

Postural control and stress reactivity were investigated in active duty coast guard personnel to determine whether they are sensitive to lifetime effects of mild traumatic brain injury (mTBI). A custom-designed and validated virtual reality-based computerized posturography device was used to assess postural stability, whereas emotional reactivity was assessed using the acoustic startle response (ASR), and neurocognitive performance was assessed using the defense-automated neurobehavioral assessment (DANA). It was hypothesized that residual and subtle postural control imbalance and deficits in cognitive and sensory reactivity would be evident in those reporting multiple lifetime mTBI. Active duty military personnel (N = 36; 7 females and 29 males) with no Deployment Limiting Medical Condition were recruited and tested on all assessments. Medical history information provided a history of head injury. Thirty-nine percent of participants reported having a previous mTBI (nine reporting one and five reporting more than one incident). No participant had experienced a head injury within the past year and all were symptom free. A significant effect of number of mTBI was found in the postural assessment (p = 0.002). Lifetime mTBI was associated with suppressed ASR magnitude (p = 0.03) but did not affect neurocognitive performance. The current findings provide new insight into ongoing controversies concerning sensitivity to functional deficits following mTBI and when the window for treatment or restoration ends.

Implication of Posture Analysing Software to Evaluate the Postural Changes after Corrective Exercise Strategy on Subjects with Upper Body Dysfunction-A Randomized Controlled Trial

PubMed Central

Sudhakar, S; Porcelvan, S; Francis, T.G. Tilak; Rathnamala, D; Radhakrishnan, R

2017-01-01

Introduction The postural adaptation is very common now a days in school going children, office desk oriented job, computer users and frequent mobile users, and in all major industrial workers. Several studies have documented a high incidence of postural abnormalities in a given population; however, methods of postural measurement were poorly defined. The implication of postural pro software to analyse the postural imbalance of upper body dysfunction is very rare and literature studies says that the kinematic changes in particular segment will produce pain/discomfort and thereby lesser productivity of subjects. Aim To evaluate the postural changes in subjects with upper body dysfunction after a corrective exercise strategy using postural analysis software and pectoralis minor muscle length testing. Materials and Methods After explaining the procedure and benefits, informed consent was taken from the participating subjects (age 25-55 years). Subjects with upper body dysfunction were randomly allocated into two groups (each group 30 subjects). The Group–A received the corrective exercise strategy and Group-B received the conventional exercise for eight weeks of study duration (15 reps each exercise, total duration of 40 min; four days/week. Pre and Post posture analysis were analysed using posture pro software along with flexibility of pectoralis minor was assessed using ruler scale method. Results After interpretation of data, both the group showed the postural alteration and pectoralis minor muscle length changes, p-value (p<0.01) of both group showed highly significant changes. But comparing the both groups, the subjects who received the corrective exercise strategy shown more percentage of improvement in posture alteration (56.25%), pectoralis minor muscle length changes (68.69%) than the conventional exercise received subjects in posture alteration (24.86%) and pectoralis minor muscle length changes (21.9%). Conclusion Altered postural changes and pectoralis minor muscle flexibility before and after the corrective exercise strategy evaluated by postural analysis software method shown to be a significant tool in clinical practice, which is easier and reproducible method. PMID:28893030

Acute hemifacial dystonia possibly induced by clebopride.

PubMed

Bosco, Domenico; Plastino, Massimiliano; Marcello, Maria Giovanna; Mungari, Pasquale; Fava, Antonietta

2009-01-01

Dystonic reactions produce twisting and repetitive movements or abnormal posturing. Severe dystonic reactions have been shown to occur in concert with numerous medications. This report details the case of a patient who developed hemifacial dystonia as acute side reaction from administration of clebopride for dyspeptic prophylaxis. When the drug was immediately stopped, the dystonic posture disappeared completely within 2 weeks. The use of clebopride may be associated with not only a reversible or persistent parkinsonism syndrome but also hemifacial dystonia; therefore, attention must be drawn to this possible side effect.

Role of different sensory inputs for maintenance of body posture in sitting rat and rabbit.

PubMed

Deliagina, T; Beloozerova, I N; Popova, L B; Sirota, M G; Swadlow, H A; Grant, G; Orlovsky, G N

2000-10-01

In this paper, we describe the postural activity in sitting rats and rabbits. An animal was positioned on the platform that could be tilted in the frontal plane for up to +/-20-30 degrees, and postural corrections were video recorded. We found that in both rat and rabbit, the postural reactions led to stabilization of the dorsal-side-up trunk orientation. The result of this was that the trunk tilt constituted only approximately 50% (rat) and 25% (rabbit) of the platform tilt. In addition, in the rabbit the head orientation was also stabilized. Trunk stabilization persisted in the animals subjected to the bilateral labyrinthectomy and blindfolding, suggesting that the somatosensory input is primarily responsible for trunk stabilization. Trunk stabilization was due to extension of the limbs on the side moving down, and flexion of the opposite limbs. EMG recordings showed that the limb extension was caused by the active contraction of extensor muscles. We argue that signals from the Golgi tendon organs of the extensor muscles may considerably contribute to elicitation of postural corrective responses to the lateral tilt.

The effect of adenotonsillectomy on the position of head, cervical and thoracic spine and scapular girdle of mouth breathing children.

PubMed

Neiva, Patricia Dayrell; Franco, Letícia Paiva; Kirkwood, Renata Noce; Becker, Helena Gonçalves

2018-04-01

The clinical decision for surgical treatment of children diagnosed with mouth breathing depends on the percentage of mechanical obstruction correlated with exacerbation of upper respiratory tract infections and systemic changes. The benefits of adenotonsillectomy include changes in the nasopharyngeal space, the mandibular plane and myofunctional alterations. Post-adenotonsilectomy postural benefits have not yet been described. To investigate the kinematics of the shoulder girdle, cervical and thoracic spine in children with mouth breathing before and after adenotonsillectomy. Forty-nine mouth breathing children (6.3 ± 1.8 years) of both sexes participated in the study. The measures of thoracic kyphosis, forward head position, shoulders protrusion and abduction, elevation, anterior tilt and internal rotation of the scapula were evaluated before and after surgery. The kinematic data were obtained using the system Qualysis ProReflex ® . There was a significant decrease in forward head position, shoulders protrusion, elevation and anterior tilt of the scapula after surgery compared to the pre-operative. One of adenotonsillectomy results is the improvement of the posture of the head and the shoulder girdle of mouth breathing children. Clinically these findings are important and will contribute to improving the quality of life of mouth breathing children. Copyright © 2018 Elsevier B.V. All rights reserved.

Smooth-pursuit eye movements without head movement disrupt the static body balance.

PubMed

Kim, Sang-Yeob; Moon, Byeong-Yeon; Cho, Hyun Gug

2016-04-01

[Purpose] To investigate the changes of body balance in static posture in smooth-pursuit eye movements (SPEMs) without head movement. [Subjects and Methods] Forty subjects (24 males, 16 females) aged 23.24 ± 2.58 years participated. SPEMs were activated in three directions (horizontal, vertical, and diagonal movements); the target speed was set at three conditions (10°/s, 20°/s, and 30°/s); and the binocular visual field was limited to 50°. To compare the body balance changes, the general stability (ST) and the fall risk index (FI) were measured with TETRAX. The subjects wore a head-neck collar and stood on a balance plate for 32 s during each measurement in three directions. SPEMs were induced to each subject with nine target speeds and directions. All measured values were compared with those in stationary fixation. [Results] The ST and FI increased significantly in all SPEMs directions, with an increased target speed than that in stationary fixation. In the same condition of the target speed, the FI had the highest value relative to diagonal SPEMs. [Conclusion] SPEMs without head movement disrupt the stability of body balance in a static posture, and diagonal SPEMs may have a more negative effect in maintaining body balance than horizontal or vertical SPEMs.

Normative Data for the BTrackS Balance Test of Postural Sway: Results from 16,357 Community-Dwelling Individuals Who Were 5 to 100 Years Old.

PubMed

Goble, Daniel J; Baweja, Harsimran S

2018-05-17

Postural sway is routinely assessed because increased postural sway is associated with poorer performance of activities of daily living, higher rates of residential care, and increased risk of falling. Force plate technology is one of the most sensitive and objective means of assessing postural sway in the clinic. The aim of this study was to provide the first set of normative data for the BTrackS Balance Test (BBT) of postural sway. The design was descriptive and population based. BBT results from 16,357 community-dwelling individuals who were 5 to 100 years old were accumulated and assessed for effects of age, sex, height, and weight. Percentile rankings were calculated for significant groupings. BBT results were dependent on age and sex but not height or weight. Therefore, percentile rankings were determined for male and female individuals in each age category, with no consideration of participant height or weight. Data were collected by third-party practitioners with various backgrounds in more than 50 locations across the United States and Canada. There was an imbalance in the sample sizes for age and sex groupings. The findings of this study represent the largest normative dataset ever published for postural sway results. Normative data on the BBT can assist in determining abnormalities in postural sway, which have been linked to negative clinical outcomes.

'Goats that stare at men': dwarf goats alter their behaviour in response to human head orientation, but do not spontaneously use head direction as a cue in a food-related context.

PubMed

Nawroth, Christian; von Borell, Eberhard; Langbein, Jan

2015-01-01

Recently, comparative research on the mechanisms and species-specific adaptive values of attributing attentive states and using communicative cues has gained increased interest, particularly in non-human primates, birds, and dogs. Here, we investigate these phenomena in a farm animal species, the dwarf goat (Capra aegagrus hircus). In the first experiment, we investigated the effects of different human head and body orientations, as well as human experimenter presence/absence, on the behaviour of goats in a food-anticipating paradigm. Over a 30-s interval, the experimenter engaged in one of four different postures or behaviours (head and body towards the subject-'Control', head to the side, head and body away from the subject, or leaving the room) before delivering a reward. We found that the level of subjects' active anticipatory behaviour was highest in the control condition and decreased with a decreasing level of attention paid to the subject by the experimenter. Additionally, goats 'stared' (i.e. stood alert) at the experimental set-up for significantly more time when the experimenter was present but paid less attention to the subject ('Head' and 'Back' condition) than in the 'Control' and 'Out' conditions. In a second experiment, the experimenter provided different human-given cues that indicated the location of a hidden food reward in a two-way object choice task. Goats were able to use both 'Touch' and 'Point' cues to infer the correct location of the reward but did not perform above the level expected by chance in the 'Head only' condition. We conclude that goats are able to differentiate among different body postures of a human, including head orientation; however, despite their success at using multiple physical human cues, they fail to spontaneously use human head direction as a cue in a food-related context.

Update on clinical trials in Dysphagia.

PubMed

Logemann, Jeri A

2006-04-01

Randomized clinical trials (RCTs) are often known as the gold standard in treatment efficacy studies. This article defines the characteristics of RCTs and the factors that investigators must consider in designing clinical trials in dysphagia. Design issues unique to behavioral treatments often used in dysphagia are discussed. Ongoing RCTs in dysphagia are described including studies of (1) the effectiveness of the Shaker exercise versus standardized treatment in patients with severe dysphagia resulting from stroke or treatment for head and neck cancer who have been nonoral for at least three months; (2) the comparative effects of nectar- and honey-thickened liquids versus chin tuck posture and in patients with dementia or Parkinson's disease with or without dementia who aspirate on thin liquids; and (3) the comparative effects of muscle exercise versus sensory postural therapy for dysphagia resulting from treatment for head and neck cancer. Issues in generalizing from the results of clinical trials are also described.

Hemodynamics, renal function, plasma renin, and aldosterone in man after 5 to 14 days of bedrest

NASA Technical Reports Server (NTRS)

Melada, G. A.; Goldman, R. H.; Luetscher, J. A.; Zager, P. G.

1975-01-01

Continuous bedrest for 5 to 14 days had no significant effect on resting heart rate, blood pressure, or cardiac output in six normal men. Head-up tilt induced greater tachycardia in 5 of 6 patients after bed rest than in the control period. Propranolol diminished both tachycardia and the incidence of hypotension and faintness in upright posture. Plasma volume fell, extracellular fluid volume increased, and plasma renin activity was significantly elevated following bedrest. Unusually large increases in plasma renin followed head-up tilt or administration of isoproterenol during bedrest and after resuming normal activity. During bedrest, plasma aldosterone was often increased in the early morning. It is concluded that after bedrest, upright posture evokes strong beta-adrenergic activity as well as exaggerated metabolic and circulatory responses which can be reduced or abolished by the beta-adrenergic blocker, propranolol.

ITKids part II: variation of postures and muscle activity in children using different information and communication technologies.

PubMed

Ciccarelli, Marina; Straker, Leon; Mathiassen, Svend Erik; Pollock, Clare

2011-01-01

There are concerns that insufficient variation in postural and muscle activity associated with use of modern information and communication technology (ICT) presents a risk for musculoskeletal ill-health among school children. However, scientific knowledge on physical exposure variation in this group is limited. The purpose of this study was to quantify postures and muscle activity of school children using different types of ICT. Postures of the head, upper back and upper arm, and muscle activity of the right and left upper trapezius and right forearm extensors were measured over 10-12 hours in nine school children using different types of ICT at school and away-from-school. Variation in postures and muscle activity was quantified using two indices, EVA{sd} and APDF₉₀-₁₀. Paper-based (Old) ICT tasks produced postures that were less neutral but more variable than electronics-based (New ICT) and Non-ICT tasks. Non-ICT tasks involved mean postures similar to New ICT tasks, but with greater variation. Variation of muscle activity was similar between ICT types in the right and left upper trapezius muscles. Non-ICT tasks produced more muscle activity variation in the right forearm extensor group compared to New and Old ICT tasks. Different ICT tasks produce different degrees of variation in posture and muscle activity. Combining tasks that use different ICT may increase overall exposure variation. More research is needed to determine what degree of postural and muscle activity variation is associated with reduced risk of musculoskeletal ill-health.

Geometric morphometrics as a tool for improving the comparative study of behavioural postures

NASA Astrophysics Data System (ADS)

Fureix, Carole; Hausberger, Martine; Seneque, Emilie; Morisset, Stéphane; Baylac, Michel; Cornette, Raphaël; Biquand, Véronique; Deleporte, Pierre

2011-07-01

Describing postures has always been a central concern when studying behaviour. However, attempts to compare postures objectively at phylogenetical, populational, inter- or intra-individual levels generally either rely upon a few key elements or remain highly subjective. Here, we propose a novel approach, based on well-established geometric morphometrics, to describe and to analyse postures globally (i.e. considering the animal's body posture in its entirety rather than focusing only on a few salient elements, such as head or tail position). Geometric morphometrics is concerned with describing and comparing variation and changes in the form (size and shape) of organisms using the coordinates of a series of homologous landmarks (i.e. positioned in relation to skeletal or muscular cues that are the same for different species for every variety of form and function and that have derived from a common ancestor, i.e. they have a common evolutionary ancestry, e.g. neck, wings, flipper/hand). We applied this approach to horses, using global postures (1) to characterise behaviours that correspond to different arousal levels, (2) to test potential impact of environmental changes on postures. Our application of geometric morphometrics to horse postures showed that this method can be used to characterise behavioural categories, to evaluate the impact of environmental factors (here human actions) and to compare individuals and groups. Beyond its application to horses, this promising approach could be applied to all questions involving the analysis of postures (evolution of displays, expression of emotions, stress and welfare, behavioural repertoires…) and could lead to a whole new line of research.

Advantages and disadvantages of stiffness instructions when studying postural control.

PubMed

Bonnet, Cédrick T

2016-05-01

To understand the maintenance of upright stance, researchers try to discover the fundamental mechanisms and attentional resources devoted to postural control and eventually to the performance of other tasks (e.g., counting in the head). During their studies, some researchers require participants to stand as steady as possible and other simply ask participants to stand naturally. Surprisingly, a clear and direct explanation of the usefulness of the steadiness requirement seems to be lacking, both in experimental and methodological discussions. Hence, the objective of the present note was to provide advantages and disadvantages of this steadiness requirement in studies of postural control. The advantages may be to study fundamental postural control, to eliminate useless postural variability, to control spurious body motions and to control the participants' thoughts. As disadvantages, this steadiness requirement only leads to study postural control in unnatural upright stance, it changes the focus of attention (internal vs. external) and the nature of postural control (unconscious vs. conscious), it increases the difficulty of a supposedly easy control task and it eliminates or reduces the opportunity to record exploratory behaviors. When looking carefully at the four advantages of the steadiness requirement, one can believe that they are, in fact, more disadvantageous than advantageous. Overall therefore, this requirement seems illegitimate and it is proposed that researchers should not use it in the study of postural control. They may use this requirement only if they search to know the limit until which participants can consciously reduce their postural sway. Copyright © 2015 Elsevier B.V. All rights reserved.

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

PubMed

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 < .05), and static PB in the relaxed posture was significantly better than PB in all the other five conditions tested. Dynamic PB was significantly better while standing in ballet shoes with textured insoles and when standing on a spiky mat compared with all other conditions (p < .05). The practical implications derived from this study are that both male and female dancers should try to be relaxed in their postural muscles when practicing a 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.

Surface electromyography studies in standing position confirm that ankle strategy remains disturbed even following successful treatment of patients with a history of sciatica

PubMed Central

Huber, Juliusz; Lisiński, Przemysław; Ciesielska, Jagoda; Kulczyk, Aleksandra; Lipiec, Joanna; Bandosz, Agata

2016-01-01

[Purpose] It is hypothesized that ankle strategy can be changed in patients with a history of sciatica. The aim of this study was to detect residual disturbances following successful treatment. [Subjects and Methods] In patients with a history of sciatica (N=11) and pseudo-sciatica (N=9), differences in muscle activity were recorded with bilateral surface polyelectromyography and stability measurements (center of foot pressure sway and center of spectrum) in normal standing and tandem positions. Results were compared with recordings in healthy people (N=9) to identify abnormalities in electromyographic and postural studies. [Results] Increased amplitude of electromyographic recordings from the gastrocnemius and extensor digiti muscles on the affected side was detected more in patients with a history of sciatica than pseudo-sciatica syndromes in tandem position. Fewer amplitude fluctuations were observed in both positions preferably in patients following sciatica. Changes in center of foot pressure sway and center of spectrum during balance platform studies were detected in normal standing position in this group of patients. No similar abnormalities in electromyographic and postural studies were detected in healthy people. [Conclusion] Sciatica and pseudo-sciatica evoke persistent disturbances in activity of muscles responsible for ankle strategy. Electromyography differentiates the two groups of patients better than postural studies. PMID:27065544

Tilt angles and positive response of head-up tilt test in children with orthostatic intolerance.

PubMed

Lin, Jing; Wang, Yuli; Ochs, Todd; Tang, Chaoshu; Du, Junbao; Jin, Hongfang

2015-01-01

This study aimed at examining three tilt angle-based positive responses and the time to positive response in a head-up tilt test for children with orthostatic intolerance, and the psychological fear experienced at the three angles during head-up tilt test. A total of 174 children, including 76 boys and 98 girls, aged from 4 to 18 years old (mean 11.3±2.8 years old), with unexplained syncope, were randomly divided into three groups, to undergo head-up tilt test at the angles of 60°, 70° and 80°, respectively. The diagnostic rates and times were analysed, and Wong-Baker face pain rating scale was used to access the children's psychological fear. There were no significant differences in diagnostic rates of postural orthostatic tachycardia syndrome and vasovagal syncope at different tilt angles during the head-up tilt test (p>0.05). There was a significant difference, however, in the psychological fear at different tilt angles utilising the Kruskal-Wallis test (χ2=36.398, p<0.01). It was mildest at tilt angle 60° utilising the Kolmogorov-Smirnov test (p<0.01). A positive rank correlation was found between the psychological fear and the degree of tilt angle (r(s)=0.445, p<0.01). Positive response appearance time was 15.1±14.0 minutes at 60° for vasovagal syncope children. There was no significant difference in the time to positive response, at different tilt angles during the head-up tilt test for vasovagal syncope or for postural orthostatic tachycardia syndrome. Hence, it is suggested that a tilt angle of 60° and head-up tilt test time of 45 minutes should be suitable for children with vasovagal syncope.

Comparative analysis of assessment of the craniocervical equilibrium through two methods: cephalometry of Rocabado and cervical range of motion.

PubMed

de Oliveira, Lilian Becerra; Cajaíba, Franklin; Costa, Wesley; Rocabado, Mariano; Lazo-Osório, Rodrigo; Ribeiro, Sanzia

2012-01-01

There are several instruments of evaluation of the craniocervical equilibrium; the most reliable are the radiographies. This study used the cephalometric analysis of Rocabado to measure the sensibility and specificity of the Cervical Range of Motion (CROM), a goniometer designed to assess cervical movements in degrees, and measure the forward head position in centimeters. This instrument frequently used, has been tested as a reliable instrument to evaluate the cervical movements but not the forward head. The sample consisted of 30 volunteers, 18 females, 12 males, mean age of 24.63 years. All participants were evaluated with CROM and radiographies in the resting head position and in erect head position. The values considered by the cephalometry consisted in the angle made between the McGregor plane and the vertical line formed by the base of the odontoid process to its apex; the posterior space between C0-C1 and C1-C2 and the hyoid triangle. 30% of the subjects had forward head posture, according to de cephalometry of Rocabado (decreased space between C0-C1, C1-C2) and 43,3% according to CROM. 16,6% had decreased posterior-inferior angle, and 13% had the hyoid triangle facing up. ROC curve of identifying forward head posture yielded area under the curve of 0,778 (95% confidence interval 0,596-0,960). The sensibility of CROM was: 77%. The specificity 71%. This study suggests that CROM has a moderate sensibility and specificity, useful for clinic use, but not for research.

Neck posture and muscle activity are different when upside down: a human volunteer study.

PubMed

Newell, Robyn S; Blouin, Jean-Sébastien; Street, John; Cripton, Peter A; Siegmund, Gunter P

2013-11-15

Rollover crashes are dynamic and complex events in which head impacts with the roof can cause catastrophic neck injuries. Ex vivo and computational models are valuable in understanding, and ultimately preventing, these injuries. Although neck posture and muscle activity influence the resulting injury, there is currently no in vivo data describing these parameters immediately prior to a head-first impact. The specific objectives of this study were to determine the in vivo neck vertebral alignment and muscle activation levels when upside down, a condition that occurs during a rollover. Eleven human subjects (6F, 5M) were tested while seated upright and inverted in a custom-built apparatus. Vertebral alignment was measured using fluoroscopy and muscle activity was recorded using surface and indwelling electrodes in eight superficial and deep neck muscles. In vivo vertebral alignment and muscle activation levels differed between the upright and inverted conditions. When inverted and relaxed, the neck was more lordotic, C1 was aligned posterior to C7, the Frankfort plane was extended, and the activity of six muscles increased compared to upright and relaxed. When inverted subjects were asked to look forward to eliminate head extension, flexor muscle activity increased, C7 was more flexed, and C1 was aligned anterior to C7 versus upright and relaxed. Combined with the large inter-subject variability observed, these findings indicate that cadaveric or computational models designed to study injuries and prevention devices while inverted need to consider a variety of postures and muscle conditions to be relevant to the in vivo situation. © 2013 Elsevier Ltd. All rights reserved.

Neuromuscular Impairments Are Associated With Impaired Head and Trunk Stability During Gait in Parkinson Fallers.

PubMed

Cole, Michael H; Naughton, Geraldine A; Silburn, Peter A

2017-01-01

Background The trunk plays a critical role in attenuating movement-related forces that threaten to challenge the body's postural control system. For people with Parkinson's disease (PD), disease progression often leads to dopamine-resistant axial symptoms, which impair trunk control and increase falls risk. Objective This prospective study aimed to evaluate the relationship between impaired trunk muscle function, segmental coordination, and future falls in people with PD. Methods Seventy-nine PD patients and 82 age-matched controls completed clinical assessments and questionnaires to establish their medical history, symptom severity, balance confidence, and falls history. Gait characteristics and trunk muscle activity were assessed using 3-dimensional motion analysis and surface electromyography. The incidence, cause, and consequence of any falls experienced over the next 12 months were recorded and indicated that 48 PD and 29 control participants fell at least once during this time. Results PD fallers had greater peak and baseline lumbar multifidus (LMF) and thoracic erector spinae (TES) activations than control fallers and nonfallers. Analysis of covariance indicated that the higher LMF activity was attributable to the stooped posture adopted by PD fallers, but TES activity was independent of medication use, symptom severity, and trunk orientation. Furthermore, greater LMF and TES baseline activity contributed to increasing lateral head, trunk, and pelvis movements in PD fallers but not nonfallers or controls. Conclusions The results provide evidence of neuromuscular deficits for PD fallers that are independent of medications, symptom severity, and posture and contribute to impaired head, trunk, and pelvis control associated with falls in this population. © The Author(s) 2016.

Position of document holder and work related risk factors for neck pain among computer users: a narrative review.

PubMed

Ambusam, S; Baharudin, O; Roslizawati, N; Leonard, J

2015-01-01

Document holder is used as a remedy to address occupational neck pain among computer users. An understanding on the effects of the document holder along with other work related risk factors while working in computer workstation requires attention. A comprehensive knowledge on the optimal location of the document holder in computer use and associated work related factors that may contribute to neck pain reviewed in this article. A literature search has been conducted over the past 14 years based on the published articles from January 1990 to January 2014 in both Science Direct and PubMed databases. Medical Subject Headings (MeSH) keywords for search were neck muscle OR head posture OR muscle tension' OR muscle activity OR work related disorders OR neck pain AND/OR document location OR document holder OR source document OR copy screen holder.Document holder placed lateral to the screen was most preferred to reduce neck discomfort among occupational typists. Document without a holder was placed flat on the surface is least preferred. The head posture and muscle activity increases when the document is placed flat on the surface compared to when placed on the document holder. Work related factors such as static posture, repetitive movement, prolong sitting and awkward positions were the risk factors for chronic neck pain. This review highlights the optimal location for document holder for computer users to reduce neck pain. Together, the importance of work related risk factors for to neck pain on occupational typist is emphasized for the clinical management.

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?

PubMed

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.

First-Person Perspective Virtual Body Posture Influences Stress: A Virtual Reality Body Ownership Study

PubMed Central

Bergström, Ilias; Kilteni, Konstantina; Slater, Mel

2016-01-01

In immersive virtual reality (IVR) it is possible to replace a person’s real body by a life-sized virtual body that is seen from first person perspective to visually substitute their own. Multisensory feedback from the virtual to the real body (such as the correspondence of touch and also movement) can also be present. Under these conditions participants typically experience a subjective body ownership illusion (BOI) over the virtual body, even though they know that it is not their real one. In most studies and applications the posture of the real and virtual bodies are as similar as possible. Here we were interested in whether the BOI is diminished when there are gross discrepancies between the real and virtual body postures. We also explored whether a comfortable or uncomfortable virtual body posture would induce feelings and physiological responses commensurate with the posture. We carried out an experiment with 31 participants in IVR realized with a wide field-of-view head-mounted display. All participants were comfortably seated. Sixteen of them were embodied in a virtual body designed to be in a comfortable posture, and the remainder in an uncomfortable posture. The results suggest that the uncomfortable body posture led to lesser subjective BOI than the comfortable one, but that participants in the uncomfortable posture experienced greater awareness of their autonomic physiological responses. Moreover their heart rate, heart rate variability, and the number of mistakes in a cognitive task were associated with the strength of their BOI in the uncomfortable posture: greater heart rate, lower heart rate variability and more mistakes were associated with higher levels of the BOI. These findings point in a consistent direction—that the BOI over a body that is in an uncomfortable posture can lead to subjective, physiological and cognitive effects consistent with discomfort that do not occur with the BOI over a body in a comfortable posture. PMID:26828365

Analysis of abnormalities in pituitary gland in non-missile head injury: study of 100 consecutive cases.

PubMed Central

Harper, C G; Doyle, D; Adams, J H; Graham, D I

1986-01-01

Pituitary glands, obtained at necropsy from a consecutive series of 100 patients who had died as a result of non-missile head injuries, were examined to define the incidence and pathogenesis of abnormality. Images PMID:3734113

Biomedical Analyses, Tolerance, and Mitigation of Acute and Chronic Trauma

DTIC Science & Technology

2012-07-01

aligned such that in one group the heads were constrained to rotate in the mid-sagittal line and in the other group head was angulated about all three...the restrained than in the unrestrained groups indicating the role of posture on trauma. Uniaxial force gages introduced into the C5-C6...directions for future experimental design. Tests conducted on the Hybrid-III ATD with both curved and straightened lumbar spines demonstrated that

Head stabilisation in fast running lizards.

PubMed

Goyens, Jana; Aerts, Peter

2018-04-01

The cyclic patterns of terrestrial animal locomotion are frequently perturbed in natural environments. The terrain can be complex or inclined, the substrate can move unexpectedly and animals can misjudge situations. Loosing stability due to perturbations increases the probability of capture by predators and decreases the chance of successful prey capture and winning intraspecific battles. When controlled corrective actions are necessary to negotiate perturbations, animals rely on their exteroceptive and proprioceptive senses to monitor the environment and their own body movements. The vestibular system in the inner ear perceives linear and angular accelerations. This information enables gaze stabilisation and the creation of a stable, world-bound reference frame for the integration of the information of other senses. During locomotion, both functions are known to be facilitated by head stabilisation in several animals with an erect posture. Animals with a sprawled body posture, however, undergo very large body undulations while running. Using high speed video recordings, we tested whether they nevertheless stabilise their head during running, and how this is influenced by perturbations. We found that running Acanthodactylus boskianus lizards strongly stabilise their head yaw rotations when running on a flat, straight runway: the head rotation amplitude is only 4.76±0.99°, while the adjacent trunk part rotates over 27.0±3.8°. Lateral head translations are not stabilised (average amplitude of 7.4±2.0mm). When the lizards are experimentally perturbed by a large and unexpected lateral substrate movement, lateral translations of both the head and the body decrease (on average by 1.52±0.81mm). At the same time, the rotations of the head and trunk also decrease (on average by 1.62°±7.21°). These results show that head stabilisation intensifies because of the perturbation, which emphasises the importance of vestibular perception and balance in these fast and manoeuvrable animals. Copyright © 2017 Elsevier GmbH. All rights reserved.

Mechanisms of rotator cuff tendinopathy: intrinsic, extrinsic, or both?

PubMed

Seitz, Amee L; McClure, Philip W; Finucane, Sheryl; Boardman, N Douglas; Michener, Lori A

2011-01-01

The etiology of rotator cuff tendinopathy is multi-factorial, and has been attributed to both extrinsic and intrinsic mechanisms. Extrinsic factors that encroach upon the subacromial space and contribute to bursal side compression of the rotator cuff tendons include anatomical variants of the acromion, alterations in scapular or humeral kinematics, postural abnormalities, rotator cuff and scapular muscle performance deficits, and decreased extensibility of pectoralis minor or posterior shoulder. A unique extrinsic mechanism, internal impingement, is attributed to compression of the posterior articular surface of the tendons between the humeral head and glenoid and is not related to subacromial space narrowing. Intrinsic factors that contribute to rotator cuff tendon degradation with tensile/shear overload include alterations in biology, mechanical properties, morphology, and vascularity. The varied nature of these mechanisms indicates that rotator cuff tendinopathy is not a homogenous entity, and thus may require different treatment interventions. Treatment aimed at addressing mechanistic factors appears to be beneficial for patients with rotator cuff tendinopathy, however, not for all patients. Classification of rotator cuff tendinopathy into subgroups based on underlying mechanism may improve treatment outcomes. 2010 Elsevier Ltd. All rights reserved.

Hypovolemia in syncope and orthostatic intolerance role of the renin-angiotensin system

NASA Technical Reports Server (NTRS)

Jacob, G.; Robertson, D.; Mosqueda-Garcia, R.; Ertl, A. C.; Robertson, R. M.; Biaggioni, I.

1997-01-01

PURPOSE: Orthostatic intolerance is the cause of significant disability in otherwise normal patients. Orthostatic tachycardia is usually the dominant hemodynamic abnormality, but symptoms may include dizziness, visual changes, discomfort in the head or neck, poor concentration, fatigue, palpitations, tremulousness, anxiety and, in some cases, syncope. It is the most common disorder of blood pressure regulation after essential hypertension. There is a predilection for younger rather than older adults and for women more than men. Its cause is unknown; partial sympathetic denervation or hypovolemia has been proposed. METHODS AND MATERIALS: We tested the hypothesis that reduced plasma renin activity, perhaps from defects in sympathetic innervation of the kidney, could underlie a hypovolemia, giving rise to these clinical symptoms. Sixteen patients (14 female, 2 male) ranging in age from 16 to 44 years were studied. Patients were enrolled in the study if they had orthostatic intolerance, together with a raised upright plasma norepinephrine (> or = 600 pg/mL). Patients underwent a battery of autonomic tests and biochemical determinations. RESULTS: There was a strong positive correlation between the blood volume and plasma renin activity (r = 0.84, P = 0.001). The tachycardic response to upright posture correlated with the severity of the hypovolemia. There was also a correlation between the plasma renin activity measured in these patients and their concomitant plasma aldosterone level. CONCLUSIONS: Hypovolemia occurs commonly in orthostatic intolerance. It is accompanied by an inappropriately low level of plasma renin activity. The degree of abnormality of blood volume correlates closely with the degree of abnormality in plasma renin activity. Taken together, these observations suggest that reduced plasma renin activity may be an important pathophysiologic component of the syndrome of orthostatic intolerance.

Vestibular rehabilitation therapy: review of indications, mechanisms, and key exercises.

PubMed

Han, Byung In; Song, Hyun Seok; Kim, Ji Soo

2011-12-01

Vestibular rehabilitation therapy (VRT) is an exercise-based treatment program designed to promote vestibular adaptation and substitution. The goals of VRT are 1) to enhance gaze stability, 2) to enhance postural stability, 3) to improve vertigo, and 4) to improve activities of daily living. VRT facilitates vestibular recovery mechanisms: vestibular adaptation, substitution by the other eye-movement systems, substitution by vision, somatosensory cues, other postural strategies, and habituation. The key exercises for VRT are head-eye movements with various body postures and activities, and maintaining balance with a reduced support base with various orientations of the head and trunk, while performing various upper-extremity tasks, repeating the movements provoking vertigo, and exposing patients gradually to various sensory and motor environments. VRT is indicated for any stable but poorly compensated vestibular lesion, regardless of the patient's age, the cause, and symptom duration and intensity. Vestibular suppressants, visual and somatosensory deprivation, immobilization, old age, concurrent central lesions, and long recovery from symptoms, but there is no difference in the final outcome. As long as exercises are performed several times every day, even brief periods of exercise are sufficient to facilitate vestibular recovery. Here the authors review the mechanisms and the key exercises for each of the VRT goals.

Vestibular Rehabilitation Therapy: Review of Indications, Mechanisms, and Key Exercises

PubMed Central

Song, Hyun Seok; Kim, Ji Soo

2011-01-01

Vestibular rehabilitation therapy (VRT) is an exercise-based treatment program designed to promote vestibular adaptation and substitution. The goals of VRT are 1) to enhance gaze stability, 2) to enhance postural stability, 3) to improve vertigo, and 4) to improve activities of daily living. VRT facilitates vestibular recovery mechanisms: vestibular adaptation, substitution by the other eye-movement systems, substitution by vision, somatosensory cues, other postural strategies, and habituation. The key exercises for VRT are head-eye movements with various body postures and activities, and maintaining balance with a reduced support base with various orientations of the head and trunk, while performing various upper-extremity tasks, repeating the movements provoking vertigo, and exposing patients gradually to various sensory and motor environments. VRT is indicated for any stable but poorly compensated vestibular lesion, regardless of the patient's age, the cause, and symptom duration and intensity. Vestibular suppressants, visual and somatosensory deprivation, immobilization, old age, concurrent central lesions, and long recovery from symptoms, but there is no difference in the final outcome. As long as exercises are performed several times every day, even brief periods of exercise are sufficient to facilitate vestibular recovery. Here the authors review the mechanisms and the key exercises for each of the VRT goals. PMID:22259614

Diurnal changes in postural control in normal children: Computerized static and dynamic assessments.

PubMed

Bourelle, Sophie; Taiar, Redha; Berge, Benoit; Gautheron, Vincent; Cottalorda, Jerome

2014-01-01

Mild traumatic brain injury (mTBI) causes postural control deficits and accordingly comparison of aberrant postural control against normal postural control may help diagnose mTBI. However, in the current literature, little is known regarding the normal pattern of postural control in young children. This study was therefore conducted as an effort to fill this knowledge gap. Eight normal school-aged children participated. Posture assessment was conducted before (7-8 a.m. in the morning) and after (4-7 p.m. in the afternoon) school on regular school days using the Balance Master® evaluation system composed of 3 static tests and 2 dynamic balance tests. A significant difference in the weight-bearing squats was detected between morning hours and afternoon hours (P < 0.05). By end of afternoon, the body weight was borne mainly on the left side with the knee fully extended and at various degrees of knee flexion. A significantly better directional control of the lateral rhythmic weight shifts was observed at the end of the afternoon than at morning hours (P < 0.05). In summary, most of our findings are inconsistent with results from previous studies in adults, suggesting age-related differences in posture control in humans. On a regular school day, the capacity of postural control and laterality or medio-lateral balance in children varies between morning and afternoon hours. We suggest that posturographic assessment in children, either in normal (e.g., physical education and sports training) or in abnormal conditions (e.g., mTBI-associated balance disorders), be better performed late in the afternoon.

Technetium-99m-HMPAO SPECT in the evaluation of patients with a remote history of traumatic brain injury: a comparison with x-ray computed tomography.

PubMed

Gray, B G; Ichise, M; Chung, D G; Kirsh, J C; Franks, W

1992-01-01

The functional imaging modality has potential for demonstrating parenchymal abnormalities not detectable by traditional morphological imaging. Fifty-three patients with a remote history of traumatic brain injury (TBI) were studied with SPECT using 99mTc-hexamethylpropyleneamineoxime (HMPAO) and x-ray computed tomography (CT). Overall, 42 patients (80%) showed regional cerebral blood flow (rCBF) deficits by HMPAO SPECT, whereas 29 patients (55%) showed morphological abnormalities by CT. Out of 20 patients with minor head injury, 12 patients (60%) showed rCBF deficits and 5 patients (25%) showed CT abnormalities. Of 33 patients with major head injury, 30 patients (90%) showed rCBF deficits and 24 patients (72%) showed CT abnormalities. Thus, HMPAO SPECT was more sensitive than CT in detecting abnormalities in patients with a history of TBI, particularly in the minor head injury group. In the major head injury group, three patients showed localized cortical atrophy by CT and normal rCBF by HMPAO SPECT. In the evaluation of TBI patients, HMPAO SPECT is a useful technique to demonstrate regional brain dysfunction in the presence of morphological integrity as assessed by CT.

Test-retest reliability of posture measurements in adolescents with idiopathic scoliosis.

PubMed

Heitz, Pierre-Henri; Aubin-Fournier, Jean-François; Parent, Éric; Fortin, Carole

2018-05-07

Posture changes are a major consequence of IS (IS). Posture changes can lead to psychosocial and physical impairments in adolescents with IS. Therefore, it is important to assess posture but the test-retest reliability of posture measurements still remains unknown in this population. The primary objective was to determine the test-retest reliability of 25 head and trunk posture indices using the Clinical Photographic Postural Assessment Tool (CPPAT) in adolescents with IS. The secondary objective was to determine the standard error of measurement and the minimal detectable change. This is a prospective test-retest reliability study carried out at two tertiary university hospital centers. Forty-one adolescents with IS, aged 10 to 16 years old with curves 10 to 45 o and treated non-operatively were recruited. Two posture assessments were done using the CPPAT five to 10 days apart following a standardized procedure. Photographs were analyzed with the CPPAT software by digitizing reference landmarks placed on the participant by a physiotherapist evaluator. Generalizability theory was used to obtain a coefficient of dependability, standard error of measurement and the minimal detectable change at the 90% confidence interval. This project was supported by the Canadian Pediatric Spine Society (CPSS: 10000$). There is no study-specific conflicts of interest-associated biases. Fourteen of 25 posture indices had a good reliability (ϕ ≥ 0.78), ten of 25 had moderate reliability (ϕ = 0.55 to 0.74) and one had poor reliability (ϕ = 0.45). The most reliable posture indices were waist angles asymmetry (ϕ = 0.93), right waist angle (ϕ = 0.91) and frontal trunk list (ϕ = 0.92). Right sagittal trunk list was the least reliable posture index (ϕ = 0.45). The MDC 90 values ranged from 2.6 to 10.3° for angular measurements and from 8.4 to 35.1 mm for linear measurements. This study demonstrates that most posture indices, especially the trunk posture indices, are reproducible in time among adolescents with IS and provides reference values. Clinicians and researchers can use these reference values in order to assess change in posture over time attributable to treatment effectiveness. Copyright © 2018. Published by Elsevier Inc.

At what age is hydrocephalus detected, and what is the role of head circumference measurements?

PubMed

Breuning-Broers, Jacqueline M; Deurloo, Jacqueline A; Gooskens, Rob H; Verkerk, Paul H

2014-02-01

To investigate at what age hydrocephalus is detected and to assess the role of head circumference measurements in detecting hydrocephalus, we performed a retrospective chart review in children with hydrocephalus treated in a tertiary paediatric hospital in the Netherlands. The study group contained 146 patients; 38 patients (31%) were referred because of abnormalities in head circumference. Eighty-nine per cent of the patients were detected in the first year of life. After this period, no patients were referred because of an abnormal head circumference. Therefore, head circumference measurements seem to have little value for detecting hydrocephalus after the first year of life.

MO-C-17A-03: A GPU-Based Method for Validating Deformable Image Registration in Head and Neck Radiotherapy Using Biomechanical Modeling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neylon, J; Min, Y; Qi, S

2014-06-15

Purpose: Deformable image registration (DIR) plays a pivotal role in head and neck adaptive radiotherapy but a systematic validation of DIR algorithms has been limited by a lack of quantitative high-resolution groundtruth. We address this limitation by developing a GPU-based framework that provides a systematic DIR validation by generating (a) model-guided synthetic CTs representing posture and physiological changes, and (b) model-guided landmark-based validation. Method: The GPU-based framework was developed to generate massive mass-spring biomechanical models from patient simulation CTs and contoured structures. The biomechanical model represented soft tissue deformations for known rigid skeletal motion. Posture changes were simulated by articulatingmore » skeletal anatomy, which subsequently applied elastic corrective forces upon the soft tissue. Physiological changes such as tumor regression and weight loss were simulated in a biomechanically precise manner. Synthetic CT data was then generated from the deformed anatomy. The initial and final positions for one hundred randomly-chosen mass elements inside each of the internal contoured structures were recorded as ground truth data. The process was automated to create 45 synthetic CT datasets for a given patient CT. For instance, the head rotation was varied between +/− 4 degrees along each axis, and tumor volumes were systematically reduced up to 30%. Finally, the original CT and deformed synthetic CT were registered using an optical flow based DIR. Results: Each synthetic data creation took approximately 28 seconds of computation time. The number of landmarks per data set varied between two and three thousand. The validation method is able to perform sub-voxel analysis of the DIR, and report the results by structure, giving a much more in depth investigation of the error. Conclusions: We presented a GPU based high-resolution biomechanical head and neck model to validate DIR algorithms by generating CT equivalent 3D volumes with simulated posture changes and physiological regression.« less

Using Tri-Axial Accelerometers to Assess the Dynamic Control of Head Posture During Gait

NASA Technical Reports Server (NTRS)

Lawrence, John H., III

2003-01-01

Long duration spaceflight is known to cause a variety of biomedical stressors to the astronaut. One of the more functionally destabilizing effects of spaceflight involves microgravity-induced changes in vestibular or balance control. Balance control requires the integration of the vestibular, visual, and proprioceptive systems. In the microgravity environment, the normal gravity vector present on Earth no longer serves as a reference for the balance control system. Therefore, adaptive changes occur to the vestibular system to affect control of body orientation with altered, or non-present, gravity and/or proprioceptive inputs. Upon return to a gravity environment, the vestibular system must re-incorporate the gravity vector and gravity-induced proprioceptive inputs into the balance control regime. The result is often a period of postural instability, which may also be associated with space motion sickness (oscillopsia, nausea, and vertigo). Previous studies by the JSC Neuroscience group have found that returning astronauts often employ alterations in gait mechanics to maintain postural control during gait. It is believed that these gait alterations are meant to decrease the transfer of heel strike shock energy to the head, thus limiting the contradictory head and eye movements that lead to gait instability and motion sickness symptoms. We analyzed pre- and post-spaceflight tri-axial accelerometer data from the NASA/MIR long duration spaceflight missions to assess the heel to head transfer of heel strike shock energy during locomotion. Up to seven gait sessions (three preflight, four postflight) of head and shank (lower leg) accelerometer data was previously collected from six astronauts who engaged in space flights of four to six months duration. In our analysis, the heel to head transmission of shock energy was compared using peak vertical acceleration (a), peak jerk (j) ratio, and relative kinetic energy (a). A host of generalized movement variables was produced in an effort to isolate those that best highlighted vestibular adaptation due to spaceflight. Data suggest that astronauts used either head or body centered control to reduce the effects of heel strike shock on head position during normal walking at self-selected speeds. Moreover, the form of that control appears to fall under one of two categories: homeostatic or adaptive. Homeostatic control refers to tight constraint (small error) over the value of a given variable before and after spaceflight with little or no adaptive changes. Adaptive control refers to lesser constraint over a given movement variable with clear adaptation to earth gravity upon return from spaceflight. Heel strike shock absorption (ratio of heel to head peak acceleration) best-discriminated head and body centered control strategies. Further, peak jerk data was useful for illustrating pre- and postflight differences in segmental (shank versus head) movement energy. Results from kinetic energy analysis show high consistency between subjects and across test dates. Whether this result highlights a control strategy or is an artifact of approximating body segments using anthropometric tables is, at this point, unclear.

A non-human primate model for investigating drug-induced risk of orthostatic hypotension and sympathetic dysfunction: Preclinical correlate to a clinical test.

PubMed

Bhatt, Siddhartha; Foote, Stephen; Smith, Andrew; Butler, Paul; Steidl-Nichols, Jill

2015-01-01

Drug induced orthostatic hypotension (OH) is an important clinical concern and can be an unexpected hurdle during drug development. OH is defined as an abnormal decrease in blood pressure (BP) triggered by a rapid postural change. The sympathetic nervous system is critical for controlling normal cardiovascular function and compensatory responses to changes in posture. Thus, OH can also serve as a surrogate indicator of sympathetic dysfunction. However, preclinical conscious models for investigating risk of OH and/or sympathetic dysfunction are lacking. Herein, we describe a conscious nonhuman primate (NHP) model which mimics the widely used clinical tilt table test for OH. Male, Cynomolgus NHPs (n = 7-8) implanted with radio-telemetry transmitters were placed in modified tilt chairs in a supine position. Subsequently, a 90° head up tilt was performed for 3 min followed by return to the supine position. BP and heart rate were continuously monitored. Test compounds were administered either intravenously or via oral gavage in a crossover design, with blood samples collected at the end of the each tilt to assess total drug concentrations. Tilt responses were assessed following treatment with positive control compounds that cause sympathetic dysfunction; hexamethonium (ganglionic blocker) and prazosin (alpha-1 adrenergic receptor antagonist). Both compounds induced marked OH as evidenced by robust and sustained BP reduction in response to a head up tilt (decrease of 25-35 mmHg for hexamethonium, decrease of 21-44 mmHg for prazosin). OH incidence rates increased in a dose-dependent manner. OH incidences following treatment with minoxidil (vasodilator) were markedly lower to those observed with hexamethonium and prazosin indicating the role of sympathetic dysfunction in causing OH. These data demonstrate that the NHP tilt test is a valuable model for investigating OH risk. This model fills an important preclinical gap for assessing such a safety concern and can be applied to programs where a sympathetic deficit and/or OH are anticipated or clinically observed. Copyright © 2015 Elsevier Inc. All rights reserved.

Rehabilitation of Dysphagia Following Head and Neck Cancer

PubMed Central

Pauloski, Barbara R.

2008-01-01

SYNOPSIS Patients with cancers of the oral cavity, pharynx or larynx may be treated with surgery, radiotherapy, chemotherapy, or a combination of these modalities. Each treatment type may have a negative impact on posttreatment swallowing function; these effects are presented in this chapter. The clinician has a number of rehabilitative procedures available to reduce or eliminate swallowing disorders in patients treated for cancer of the head and neck. The various procedures--including postures, maneuvers, modifications to bolus volume and viscosity, range of motion exercises, and strengthening exercises--and their efficacy in treated head and neck cancer patients are discussed. PMID:18940647

Morphometric analysis of acetabular dysplasia in cerebral palsy: three-dimensional CT study.

PubMed

Gose, Shinichi; Sakai, Takashi; Shibata, Toru; Murase, Tsuyoshi; Yoshikawa, Hideki; Sugamoto, Kazuomi

2009-12-01

Three-dimensional computed tomography (3D-CT) eliminates the positioning errors and allows the clinician to more accurately assess the radiographic parameters present. To elucidate the 3D geometry of the acetabulum and the extent of hip subluxation/dislocation in patients with cerebral palsy (CP), quantitative morphometric analysis was performed using 3D-CT data. We evaluated 150 hips in 75 patients with bilateral spastic CP. The mean age of the patients was 5.4 years (range: 2.7 to 6.9 y). The fitting plane of the ilium was projected onto the coronal plane and then onto the sagittal plane, and then the angle formed with a horizontal line was defined as CTalpha (the lateral opening angle) and CTbeta (the sagittal inclination angle), respectively. The center of the acetabulum and the femoral head were defined, and the distance between these centers was divided by the femoral head diameter, defined as CT migration percentage (CTMP, %). In 123 (82%) of the 150 hips, the femoral head center was located posteriorly, superiorly, and laterally relative to the acetabular center. Large CTalpha cases tended to show large CTMP. CTalpha and CTMP were significantly larger in the cases with Gross Motor Functional Classification System (GMFCS) level IV/V and spastic quadriplegia, than in the cases with GMFCS level II/III and spastic diplegia. CTbeta showed significant correlation with the acetabular defect on the lateral 3D reconstructed images. Three-dimensional acetabular geometry and migration percentage in CP patients can be analyzed quantitatively using 3D-CT regardless of the abnormal spastic posture. The extent of acetabular dysplasia and subluxation is more severe in patients with GMFCS level IV/V and spastic quadriplesia. Level 4.

[Time-dependent heart rate variability in the head-up tilt test in children with postural orthostatic tachycardia syndrome].

PubMed

Ran, Jing; Wang, Cheng; Zou, Run-Mei; Wu, Li-Jia; Lin, Ping; Li, Fang; Xu, Yi

2015-10-01

To study the time-dependent heart rate (HR) variability in the head-up tilt test (HUTT) in children with postural orthostatic tachycardia syndrome (POTS) and to explore the HR diagnostic criteria for POTS in children. A retrospective analysis was performed on the clinical data of 105 children diagnosed with POTS with HR≥120 beats per minute (bpm) within the first 10 minutes of HUTT between January 2007 and December 2014. Their HR variability within the first 10 minutes of HUTT was analyzed. The HR of children with POTS increased gradually from the supine position to a 60° head-up tilt position, and the increase in HR was 24±12 bpm at the beginning of HUTT, 30±14 bpm at 3 minutes of HUTT, 32±13 bpm at 5 minutes of HUTT, and 38±12 bpm at 10 minutes of HUTT. The average maximal HR increase within the first 10 minutes of HUTT was 43±10 bpm. In children with POTS, the HR variability gradually increases with time, and therefore, it is suggested that HR increase ≥40 bpm is more suitable for diagnosis of POTS in children.

Body posture and hand strength of patients with temporomandibular disorder.

PubMed

Shiau, Y Y; Chai, H M

1990-07-01

The aim of this study was to observe the difference between patients of craniocervical muscle pain and nonpatients in head-neck posture, masticatory muscle activity, and the force exerted by the hand. Fifty-one patients and 28 nonpatients were observed. The electric activity of the masseter muscles was recorded when the subjects were doing pinching or grasping with the jaw in positions of rest, clenched, and clenched with gauze. Measurement of right and left tilting or extension and flexion of the head and neck was made from photographs of frontal and lateral views. It was found that the pinching and grasping force was much stronger in men than in women and in nonpatients than in patients with pain. The pinching and grasping force was more powerful with the teeth clenched. Clenching with gauze did not increase, but more often decreased the strength of the hand. The activity of the masseter muscle during clenching was about 10 to 26 times that of the resting activity. The activity decreased slightly when clenching with pinching or grasping. Patients were more likely to have a stretched neck with more extension of the head. Their masseter muscle activity and hand force were significantly weaker than that of the nonpatients.

Trunk, head, and step characteristics during normal and narrow-based walking under deteriorated sensory conditions.

PubMed

Deshpande, Nandini; Zhang, Fang

2014-01-01

The ability to maintain stability in the frontal plane (medialateral direction) while walking is commonly included as a component of motor performance assessment. Postural control in the frontal plane may deteriorate faster and earlier with increasing age, compared to that in the sagittal plane (anteroposterior direction). Fifteen young (20-30 years old) and 15 older (>65 years old) healthy participants were recruited to investigate age-related differences in postural control during the normal and narrow-based walking when performed under suboptimal vestibular and lower limb somatosensory conditions achieved by galvanic stimulation and compliant surfaces, respectively. Gait speed decreased in the narrow-based walking condition, with larger decrease in the elderly (by 6%). In the elderly head roll increased with perturbed vestibular information in impaired somatosensory condition (by 40.70%). In both age groups trunk roll increased under impaired somatosensation in the narrow-based walking condition (by 43.62%) but not in normal walking condition. Older participants adopted a more cautious strategy characterized by lower walking speed when walking on a narrow base and exhibited deteriorated integrative ability of the CNS for head control. Accurate lower limb somatosensation may play a critical role in narrow-based walking.

Balance ability and posture in postmenopausal women with chronic pelvic pain.

PubMed

Fuentes-Márquez, Pedro; Rodríguez-Torres, Janet R; Valenza, Marie C; Ortíz-Rubio, Araceli; Ariza-Mateos, María J; Cabrera-Martos, Irene

2018-04-09

The aim of the present study was to analyze balance ability and posture in postmenopausal women with chronic pelvic pain (CPP). This study includes a sample of 48 women with CPP recruited from the Gynecology Service of Virgen de las Nieves and San Cecilio Hospitals in Granada (Spain) and 48 healthy control women matched with respect to age and anthropometric characteristics. Outcome variables collected included: balance ability (Mini-Balance Evaluation Systems Test and Timed Up an Go Test) and posture (photogrammetry and Spinal Mouse). Significant differences were found in all Mini Best Test subscales: total (P < 0.001), anticipatory (P = 0.002), reactive postural control (P < 0.001), sensory orientation (P < 0.001), and dynamic gait (P < 0.001), and all Timed Up and Go test subscales: alone (P < 0.001), with manual (P = 0.002) and cognitive task (P = 0.030). Significant differences were also found on spinal cervical angles with a forward head posture in women with CPP; global spine alignment exhibited more deviation in the women with CPP (P < 0.001); and a higher percentage of women with CPP (58%) presented with increased thoracic kyphosis and lumbar lordosis. Cohen's d was used to calculate the effect size. Some subscales of balance and posture tests showed a large effect size (d ≥0.8), indicating a more consistent result. Women with CPP presented poor balance including anticipatory, reactive postural control, sensory orientation, dynamic gait, and dual task-related conditions. Posture showed higher values on the dorsal angle and lower sacral inclination, less spine alignment, and a more prevalent posture with increased kyphosis and lumbar lordosis.

Validity of a small low-cost triaxial accelerometer with integrated logger for uncomplicated measurements of postures and movements of head, upper back and upper arms.

PubMed

Dahlqvist, Camilla; Hansson, Gert-Åke; Forsman, Mikael

2016-07-01

Repetitive work and work in constrained postures are risk factors for developing musculoskeletal disorders. Low-cost, user-friendly technical methods to quantify these risks are needed. The aims were to validate inclination angles and velocities of one model of the new generation of accelerometers with integrated data loggers against a previously validated one, and to compare meaurements when using a plain reference posture with that of a standardized one. All mean (n = 12 subjects) angular RMS-differences in 4 work tasks and 4 body parts were <2.5° and all mean median angular velocity differences <5.0 °/s. The mean correlation between the inclination signal-pairs was 0.996. This model of the new generation of triaxial accelerometers proved to be comparable to the validated accelerometer using a data logger. This makes it well-suited, for both researchers and practitioners, to measure postures and movements during work. Further work is needed for validation of the plain reference posture for upper arms. Copyright © 2016 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Concept and Technology Exploration for Transparent Hearing

DTIC Science & Technology

2003-05-01

be seen by considering the situation in which the space is anechoic and the listener is modeled by a spherical head with ears at the ends of a ...relatively subtle changes in HRTF’s that cause only minor effects on spatial behavior , such as when a listener puts on a hat, changes their head posture...insufficient, and localization behavior can break down nearly completely [63]. However, with sufficient exposure (e.g. continuous over a period of weeks

Where You Look Matters for Body Perception: Preferred Gaze Location Contributes to the Body Inversion Effect

PubMed Central

McKean, Danielle L.; Tsao, Jack W.; Chan, Annie W.-Y.

2017-01-01

The Body Inversion Effect (BIE; reduced visual discrimination performance for inverted compared to upright bodies) suggests that bodies are visually processed configurally; however, the specific importance of head posture information in the BIE has been indicated in reports of BIE reduction for whole bodies with fixed head position and for headless bodies. Through measurement of gaze patterns and investigation of the causal relation of fixation location to visual body discrimination performance, the present study reveals joint contributions of feature and configuration processing to visual body discrimination. Participants predominantly gazed at the (body-centric) upper body for upright bodies and the lower body for inverted bodies in the context of an experimental paradigm directly comparable to that of prior studies of the BIE. Subsequent manipulation of fixation location indicates that these preferential gaze locations causally contributed to the BIE for whole bodies largely due to the informative nature of gazing at or near the head. Also, a BIE was detected for both whole and headless bodies even when fixation location on the body was held constant, indicating a role of configural processing in body discrimination, though inclusion of the head posture information was still highly discriminative in the context of such processing. Interestingly, the impact of configuration (upright and inverted) to the BIE appears greater than that of differential preferred gaze locations. PMID:28085894

Cannabis Induced Periodic Catatonia: A Case Report

ERIC Educational Resources Information Center

Bajaj, Vikrant; Pathak, Prashant; Mehrotra, Saurabh; Singh, Vijender; Govil, Sandeep; Khanna, Aman

2011-01-01

Catatonia is a syndrome of specific motor abnormalities closely associated with disorders in mood, affect, thought and cognition. The principal signs of the disorder are mutism, immobility, negativism, posturing, stereotypy and echo phenomena. Catatonia is commonly seen in various psychiatric disorders, neurological disorders and certain medical…

Loss-of-function analyses of the fragile X-related and dopamine receptor genes by RNA interference in the cricket Gryllus bimaculatus.

PubMed

Hamada, Aska; Miyawaki, Katsuyuki; Honda-sumi, Eri; Tomioka, Kenji; Mito, Taro; Ohuchi, Hideyo; Noji, Sumihare

2009-08-01

In order to explore a possibility that the cricket Gryllus bimaculatus would be a useful model to unveil molecular mechanisms of human diseases, we performed loss-of-function analyses of Gryllus genes homologous to human genes that are responsible for human disorders, fragile X mental retardation 1 (fmr1) and Dopamine receptor (DopR). We cloned cDNAs of their Gryllus homologues, Gb'fmr1, Gb'DopRI, and Gb'DopRII, and analyzed their functions with use of nymphal RNA interference (RNAi). For Gb'fmr1, three major phenotypes were observed: (1) abnormal wing postures, (2) abnormal calling song, and (3) loss of the circadian locomotor rhythm, while for Gb'DopRI, defects of wing posture and morphology were found. These results indicate that the cricket has the potential to become a novel model system to explore human neuronal pathogenic mechanisms and to screen therapeutic drugs by RNAi. Copyright (c) 2009 Wiley-Liss, Inc.

Static and dynamic posture control in postlingual cochlear implanted patients: effects of dual-tasking, visual and auditory inputs suppression

PubMed Central

Bernard-Demanze, Laurence; Léonard, Jacques; Dumitrescu, Michel; Meller, Renaud; Magnan, Jacques; Lacour, Michel

2014-01-01

Posture control is based on central integration of multisensory inputs, and on internal representation of body orientation in space. This multisensory feedback regulates posture control and continuously updates the internal model of body's position which in turn forwards motor commands adapted to the environmental context and constraints. The peripheral localization of the vestibular system, close to the cochlea, makes vestibular damage possible following cochlear implant (CI) surgery. Impaired vestibular function in CI patients, if any, may have a strong impact on posture stability. The simple postural task of quiet standing is generally paired with cognitive activity in most day life conditions, leading therefore to competition for attentional resources in dual-tasking, and increased risk of fall particularly in patients with impaired vestibular function. This study was aimed at evaluating the effects of postlingual cochlear implantation on posture control in adult deaf patients. Possible impairment of vestibular function was assessed by comparing the postural performance of patients to that of age-matched healthy subjects during a simple postural task performed in static (stable platform) and dynamic (platform in translation) conditions, and during dual-tasking with a visual or auditory memory task. Postural tests were done in eyes open (EO) and eyes closed (EC) conditions, with the CI activated (ON) or not (OFF). Results showed that the postural performance of the CI patients strongly differed from the controls, mainly in the EC condition. The CI patients showed significantly reduced limits of stability and increased postural instability in static conditions. In dynamic conditions, they spent considerably more energy to maintain equilibrium, and their head was stabilized neither in space nor on trunk: they behaved dynamically without vision like an inverted pendulum while the controls showed a whole body rigidification strategy. Hearing (prosthesis on) as well as dual-tasking did not really improve the dynamic postural performance of the CI patients. We conclude that CI patients become strongly visual dependent mainly in challenging postural conditions, a result they have to be awarded of particularly when getting older. PMID:24474907

Static and dynamic posture control in postlingual cochlear implanted patients: effects of dual-tasking, visual and auditory inputs suppression.

PubMed

Bernard-Demanze, Laurence; Léonard, Jacques; Dumitrescu, Michel; Meller, Renaud; Magnan, Jacques; Lacour, Michel

2013-01-01

Posture control is based on central integration of multisensory inputs, and on internal representation of body orientation in space. This multisensory feedback regulates posture control and continuously updates the internal model of body's position which in turn forwards motor commands adapted to the environmental context and constraints. The peripheral localization of the vestibular system, close to the cochlea, makes vestibular damage possible following cochlear implant (CI) surgery. Impaired vestibular function in CI patients, if any, may have a strong impact on posture stability. The simple postural task of quiet standing is generally paired with cognitive activity in most day life conditions, leading therefore to competition for attentional resources in dual-tasking, and increased risk of fall particularly in patients with impaired vestibular function. This study was aimed at evaluating the effects of postlingual cochlear implantation on posture control in adult deaf patients. Possible impairment of vestibular function was assessed by comparing the postural performance of patients to that of age-matched healthy subjects during a simple postural task performed in static (stable platform) and dynamic (platform in translation) conditions, and during dual-tasking with a visual or auditory memory task. Postural tests were done in eyes open (EO) and eyes closed (EC) conditions, with the CI activated (ON) or not (OFF). Results showed that the postural performance of the CI patients strongly differed from the controls, mainly in the EC condition. The CI patients showed significantly reduced limits of stability and increased postural instability in static conditions. In dynamic conditions, they spent considerably more energy to maintain equilibrium, and their head was stabilized neither in space nor on trunk: they behaved dynamically without vision like an inverted pendulum while the controls showed a whole body rigidification strategy. Hearing (prosthesis on) as well as dual-tasking did not really improve the dynamic postural performance of the CI patients. We conclude that CI patients become strongly visual dependent mainly in challenging postural conditions, a result they have to be awarded of particularly when getting older.

Amyotrophic Lateral Sclerosis

MedlinePlus

... and twitching in your arms, shoulders and tongue Difficulty holding your head up or keeping good posture ALS often starts in the hands, feet or limbs, and then spreads to other parts of your body. As the disease advances and nerve cells are destroyed, your muscles progressively ...

Temporomandibular joint dysfunction syndrome. A clinical report.

PubMed

Passero, P L; Wyman, B S; Bell, J W; Hirschey, S A; Schlosser, W S

1985-08-01

We have presented two clinical case reports of patients with TMJ dysfunction syndrome as an example of coordinated treatments between dentists and physical therapists. The clinical profiles of these patients with craniocervical pain were compiled from comprehensive physical therapy and dental-orthopedic evaluations. The significance of the relationship between the rest position of the mandible and forward head posture has been shown by the changes observed after correction of the postural deviations and vertical resting dimensions by dental treatments and physical therapy. Additional research is necessary to determine long-term effects of this combined approach in TMJ dysfunction syndrome.

Effects of dynamic head tilts on sensory organization test performance: a comparison between college-age athletes and nonathletes.

PubMed

Clark, Sean; Iltis, Peter W

2008-05-01

Controlled laboratory study. To compare postural performance measures of athletes with those of nonathletes when completing the standard Sensory Organization Test (SOT) and a modified SOT that included dynamic head tilts (DHT-SOT). Authors of recently published research have suggested that modifications to the SOT protocol (eg, introduction of pitch and roll head tilts) may enhance the test's sensitivity when assessing postural stability in individuals with higher balance capabilities or with well-compensated sensory deficits. Nineteen athletes and 19 nonathletes (group) completed both the SOT and DHT-SOT (protocol). During the SOT, participants stood upright as steadily as possible for 20 seconds during each of 6 different sensory conditions. As a variation of the SOT, the DHT-SOT incorporated active pitch and roll head tilts into the SOT protocol. Four 2-way mixed-model analyses of variance (with protocol as the repeated factor) were performed to determine if the composite equilibrium score or the visual, vestibular, or somatosensory ratio scores differed between the 2 groups across the 2 testing protocols. Significant group-by-protocol interaction effects were present for both the composite equilibrium score and visual ratio. Follow-up simple main-effects analyses indicated that these measures did not differ between groups for the SOT protocol but were significantly different on the DHT-SOT. The addition of dynamic head tilts to the SOT protocol resulted in subtle differences in balance function between athletes and nonathletes. Athletes demonstrated an increased ability to adapt to sensory disruptions during the DHT-SOT. Therapists should consider including active pitch and roll head tilts to the SOT when evaluating individuals with higher balance function or to detect subtle deficits in balance function. Diagnosis, level 3b.

Ergonomic assessment of the French and American position for laparoscopic cholecystectomy in the MIS Suite.

PubMed

Kramp, Kelvin H; van Det, Marc J; Totte, Eric R; Hoff, Christiaan; Pierie, Jean-Pierre E N

2014-05-01

Cholecystectomy was one of the first surgical procedures to be performed with laparoscopy in the 1980s. Currently, two operation setups generally are used to perform a laparoscopic cholecystectomy: the French and the American position. In the French position, the patient lies in the lithotomy position, whereas in the American position, the patient lies supine with the left arm in abduction. To find an ergonomic difference between the two operation setups the movements of the surgeon's vertebral column were analyzed in a crossover study. The posture of the surgeon's vertebral column was recorded intraoperatively using an electromagnetic motion-tracking system with three sensors attached to the head and to the trunk at the levels of Th1 and S1. A three-dimensional posture analysis of the cervical and thoracolumbar spine was performed to evaluate four surgeons removing a gallbladder in the French and American position. The body angles assessed were flexion/extension of the cervical and thoracolumbar spine, axial rotation of the cervical and thoracolumbar spine, lateroflexion of the cervical and thoracolumbar spine, and the orientation of the head in the sagittal plane. For each body angle, the mean, the percentage of operation time within an ergonomic acceptable range, and the relative frequencies were calculated and compared. No statistical difference was observed in the mean body angles or in the percentages of operation time within an acceptable range between the French and the American position. The relative frequencies of the body angles might indicate a trend toward slight thoracolumbar flexion in the French position. In a modern dedicated minimally invasive surgery suite, the body posture of the neck and trunk and the orientation of the head did not differ significantly between the French and American position.

The effectiveness of combining inspiratory muscle training with manual therapy and a therapeutic exercise program on maximum inspiratory pressure in adults with asthma: a randomized clinical trial.

PubMed

López-de-Uralde-Villanueva, Ibai; Candelas-Fernández, Pablo; de-Diego-Cano, Beatriz; Mínguez-Calzada, Orcález; Del Corral, Tamara

2018-06-01

The objective of this study was to evaluate whether the addition of manual therapy and therapeutic exercise protocol to inspiratory muscle training was more effective in improving maximum inspiratory pressure than inspiratory muscle training in isolation. This is a single-blinded, randomized controlled trial. In total, 43 patients with asthma were included in this study. The patients were allocated into one of the two groups: (1) inspiratory muscle training ( n = 21; 20-minute session) or (2) inspiratory muscle training (20-minute session) combined with a program of manual therapy (15-minute session) and therapeutic exercise (15-minute session; n = 22). All participants received 12 sessions, two days/week, for six weeks and performed the domiciliary exercises protocol. The main measures such as maximum inspiratory pressure, spirometric measures, forward head posture, and thoracic kyphosis were recorded at baseline and after the treatment. For the per-protocol analysis, between-group differences at post-intervention were observed in maximum inspiratory pressure (19.77 cmH 2 O (11.49-28.04), P < .05; F = 22.436; P < .001; η 2 p  = 0.371) and forward head posture (-1.25 cm (-2.32 to -0.19), P < .05; F = 5.662; P = .022; η 2 p  = 0.13). The intention-to-treat analysis showed the same pattern of findings. The inspiratory muscle training combined with a manual therapy and therapeutic exercise program is more effective than its application in isolation for producing short-term maximum inspiratory pressure and forward head posture improvements in patients with asthma.

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

PubMed

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 perception of their postural limitation boundary towards target directions and reduced time to correct this error during dynamic postural sways but not during static stance. Regarding postural equilibrium, they showed a compromised ability to decouple ankle dorsi-/plantar-flexion and hip abduction/adduction processes during dynamic stances. These results suggest that deficits in both postural orientation and equilibrium processes contribute to reduced postural stability in ASD. Specifically, increased postural sway in ASD appears to reflect patients' impaired perception of their body movement relative to their own postural limitation boundary as well as a reduced ability to decouple distinct ankle and hip movements to align their body during standing. Our findings that deficits in postural orientation and equilibrium are more pronounced during dynamic compared to static stances suggests that the increased demands of everyday activities in which children must dynamically shift their COP involve more severe postural control deficits in ASD relative to static stance conditions that often are studied. Systematic assessment of dynamic postural control processes in ASD may provide important insights into new treatment targets and neurodevelopmental mechanisms.

Bilaterally Abnormal Head Impulse Tests Indicate a Large Cerebellopontine Angle Tumor.

PubMed

Kim, Hyo Jung; Park, Seong Ho; Kim, Ji Soo; Koo, Ja Won; Kim, Chae Yong; Kim, Young Hoon; Han, Jung Ho

2016-01-01

Tumors involving the cerebellopontine angle (CPA) pose a diagnostic challenge due to their diverse manifestations. Head impulse tests (HITs) have been used to evaluate vestibular function, but few studies have explored the head impulse gain of the vestibulo-ocular reflex (VOR) in patients with a vestibular schwannoma. This study tested whether the head impulse gain of the VOR is an indicator of the size of a unilateral CPA tumor. Twenty-eight patients (21 women; age=64±12 years, mean±SD) with a unilateral CPA tumor underwent a recording of the HITs using a magnetic search coil technique. Patients were classified into non-compressing (T1-T3) and compressing (T4) groups according to the Hannover classification. Most (23/28, 82%) of the patients showed abnormal HITs for the semicircular canals on the lesion side. The bilateral abnormality in HITs was more common in the compressing group than the non-compressing group (80% vs. 8%, Pearson's chi-square test: p<0.001). The tumor size was inversely correlated with the head impulse gain of the VOR in either direction. Bilaterally abnormal HITs indicate that a patient has a large unilateral CPA tumor. The abnormal HITs in the contralesional direction may be explained either by adaptation or by compression and resultant dysfunction of the cerebellar and brainstem structures. The serial evaluation of HITs may provide information on tumor growth, and thereby reduce the number of costly brain scans required when following up patients with CPA tumors.

Assessment of dental student posture in two seating conditions using RULA methodology - a pilot study.

PubMed

Gandavadi, A; Ramsay, J R E; Burke, F J T

2007-11-24

To assess dental students' posture on two different seats in order to determine if one seat predisposes to a difference in working posture. A between-subject experimental design was selected. The study was undertaken at the University of Birmingham School of Dentistry in 2006. Subjects (materials) and methods Sixty second year dental students at the University of Birmingham who were attending their fi rst classes in the phantom head laboratory were randomly selected and allocated to two different seats (30 Bambach Saddle Seats and 30 conventional seats). Students were trained in the use of the seats. After ten weeks, the students were observed, photographs were taken by the researcher and these were assessed using Rapid Upper Limb Assessment (RULA). The posture of the students was assessed using the RULA. Each student was given a risk score. A Mann Whitney test was used for statistical analysis. The results indicated that the students using the conventional seat recorded significantly higher risk scores (p <0.05) when compared with the students using Bambach Saddle Seat, suggesting an improvement in posture when using the Bambach Saddle Seat. RULA has identified that dental students using a Bambach Saddle Seat were able to maintain an acceptable working posture during simulated dental treatment and this seating may reduce the development of work-related musculoskeletal disorders.

Specificity of postural sway to the demands of a precision task at sea.

PubMed

Chen, Fu-Chen; Stoffregen, Thomas A

2012-06-01

Mariners actively adjust their body orientation in response to ship motion. On a ship at sea, we evaluated relations between standing postural activity and the performance of a precision aiming task. Standing participants (experienced mariners) maintained the beam from a handheld laser on a target. Targets were large or small, thereby varying the difficulty of the aiming task. Targets were located in front of the participant or to the participant's right (requiring participants to look over the right shoulder), thereby varying the functional consequences (for the aiming task) of postural activity in different body axes. The torso was oriented toward the bow or toward the ship's side (athwartship), thereby varying the effects on postural activity of differential motion of the ship in its different axes. The weather was rough, producing high magnitudes of ship motion, which sometimes caused participants to step or stagger. Our manipulations influenced the magnitude and dynamics of head and torso movements, as well as the organization of movement in different axes. The results provide the first empirical confirmation that postural activity can be influenced by orientation of the torso relative to a ship. Despite powerful effects of ship motion, postural activity was influenced by variations in target location and in the difficulty of the aiming task, replicating subtle effects that have been observed on land. We discuss implications for hull design and the placement of workstations on ships.

Design of a steering stabilizer based on CAN bus

NASA Astrophysics Data System (ADS)

Zhan, Zhaomin; Yan, Yibin

2018-04-01

This design realizes a posture correction device of griping steering wheel based on CAN bus, which is embedded in the steering wheel of vehicles. The system aims to detect the drivers' abnormal griping postures and provides drivers with classification alerts, by combining the recorded griping postures data and the vehicle speed data that are obtained via the CAN bus. The warning information are automatically stored and retained in the device for 12 months. To enhance the alerting effect, the count of this warning message for both the latest month and the last 12 months are displayed on the dashboard panel. In addition to prevent itself from being blocked and self-detect any faults in advance, the appliance also provide a self-test function, which will communicate with the integrated instrument system in vehicle and do simulation test right after the vehicle power on. This appliance can help to urge and ensure drivers to operate the steering wheel correctly, effectively, and timely; prevent some typical incorrect behaviors which commonly happen along with the change of griping postures, such as the using cellphone, and ultimately, reduce the incidence of traffic accidents.

Planus Foot Posture and Pronated Foot Function are Associated with Foot Pain: The Framingham Foot Study

PubMed Central

Menz, Hylton B.; Dufour, Alyssa B.; Riskowski, Jody L.; Hillstrom, Howard J.; Hannan, Marian T.

2014-01-01

Objective To examine the associations of foot posture and foot function to foot pain. Methods Data were collected on 3,378 members of the Framingham Study who completed foot examinations in 2002–2008. Foot pain (generalized and at six locations) was based on the response to the question “On most days, do you have pain, aching or stiffness in either foot?” Foot posture was categorized as normal, planus or cavus using static pressure measurements of the arch index. Foot function was categorized as normal, pronated or supinated using the center of pressure excursion index from dynamic pressure measurements. Sex-specific multivariate logistic regression models were used to examine the effect of foot posture and function on generalized and location-specific foot pain, adjusting for age and weight. Results Planus foot posture was significantly associated with an increased likelihood of arch pain in men (odds ratio [OR] 1.38, 95% confidence interval [CI] 1.01 – 1.90), while cavus foot posture was protective against ball of foot pain (OR 0.74, 95% CI 0.55 – 1.00) and arch pain (OR 0.64, 95% CI 0.48 – 0.85) in women. Pronated foot function was significantly associated with an increased likelihood of generalized foot pain (OR 1.28, 95% CI 1.04 – 1.56) and heel pain (OR 1.54, 95% CI 1.04 – 2.27) in men, while supinated foot function was protective against hindfoot pain in women (OR 0.74, 95% CI 0.55 – 1.00). Conclusion Planus foot posture and pronated foot function are associated with foot symptoms. Interventions that modify abnormal foot posture and function may therefore have a role in the prevention and treatment of foot pain. PMID:23861176

Assessing stability in mild and moderate Parkinson's disease: Can clinical measures provide insight?

PubMed

Hubble, Ryan P; Silburn, Peter A; Naughton, Geraldine A; Cole, Michael H

2016-09-01

This cross-sectional study aimed to investigate the relationship between accelerometer-derived measures of movement rhythmicity and clinical measures of mobility, balance confidence and gait difficulty in people with Parkinson's disease (PD). Twenty-nine independently-living PD patients (Hoehn & Yahr Stages 1-3) with no history of significant injury or orthopaedic/deep brain stimulation surgery were recruited from a database of patients who had expressed an interest to participate in research. Participants completed clinical assessments of mobility, postural stability, balance confidence and symptom severity, while head and trunk rhythmicity was evaluated during gait using accelerometers. Following data collection, patients were stratified based on disease stage into either a Mild (Hoehn & Yahr Stage 1) or Moderate (Hoehn & Yahr Stages 2-3) PD group. The results highlighted that the Moderate PD group had poorer quality of life, reduced balance confidence and increased gait and falls difficulty. Furthermore, for these patients, gait disability and the number of previous falls were both negatively correlated with multiple components of head and trunk rhythmicity. For the Mild PD group, six-meter walk time was positively correlated with ML head rhythmicity and linear regression highlighted a significant predictive relationship between these outcomes. For the Mild and Moderate PD groups, balance confidence respectively predicted anterior-posterior trunk rhythmicity and vertical head rhythmicity. While these findings demonstrate that falls history and the Gait and Falls questionnaire provide moderate insight into head and trunk rhythmicity in Moderate PD patients, objective and clinically-feasible measures of postural instability would assist with the management of these symptoms. Copyright © 2016 Elsevier B.V. All rights reserved.

Head Injury and the Post-Trauma Vision Syndrome.

ERIC Educational Resources Information Center

Padula, William V.; Shapiro, Jannie B.

1993-01-01

This article considers the visual rehabilitation of patients recovering from traumatic brain injuries. Characteristics, symptoms, and associated neuromotor difficulties of posttrauma vision syndrome are listed, as are common posture and gait adaptations. A neuro-optometric rehabilitative and orientation/mobility evaluation is recommended, as is…

Infusions of muscimol into the lateral septum do not reduce rats' defensive behaviors toward a cat odor stimulus.

PubMed

Chee, San-San A; Patel, Ronak; Menard, Janet L

2015-01-01

The lateral septum (LS) is implicated in behavioral defense. We tested whether bilateral infusions of the GABAA receptor agonist muscimol into the LS suppress rats' defensive responses to cat odor. Rats received intra-LS infusions of either saline or muscimol (40 ng/rat) and were exposed to either a piece of a cat collar that had been previously worn by a cat or to a control (cat odor free) collar. Rats exposed to the cat odor collar displayed more head-out postures, while intra-LS application of muscimol reduced the number of head-out postures. However, this reduction was also present in rats exposed to a control (cat odor free) collar. This latter finding suggests that despite its involvement in other defensive behaviors (e.g., open arm avoidance in the elevated plus maze), the LS does not selectively regulate rats' receptor defensive responding to the olfactory cues present in our cat odor stimulus. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Postural profile and falls of osteoporotic women.

PubMed

Karakasidou, Palina; Skordilis, Emmanouil K; Dontas, Ismene; Lyritis, George P

2012-01-01

1. To compare postural alignment in erect standing between osteoporotic fallers, osteoporotic non-fallers and healthy women. 2. To compare BMI, number of fractures and intensity of pain between osteoporotic fallers and non-fallers. Thirty-six osteoporotic women with vertebral fractures and 40 healthy women participated in the study. Spinal curvatures were assessed with a digital inclinometer. Photographic measurements of knee, hip, shoulder and head were carried out in sagittal plane. Significant differences were found between osteoporotic fallers and healthy women in the head (p=0.040), and thoracic angles (p=0.001). Significant differences were found between fallers and non-fallers in BMI (p=0.000), number of fractures (p=0.033) and pain (p=0.005), with fallers being heavier, with less fractures and pain than non-fallers. Osteoporotic fallers probably differ from osteoporotic non-fallers and healthy women. Researchers and clinicians may consider, in the future, the above differences when planning research and clinical intervention in this field. Replication studies are necessary to confirm the present findings.

Crawling and walking infants see the world differently

PubMed Central

Kretch, Kari S.; Franchak, John M.; Adolph, Karen E.

2013-01-01

How does visual experience change over development? To investigate changes in visual input over the developmental transition from crawling to walking, thirty 13-month-olds crawled or walked down a straight path wearing a head-mounted eye-tracker that recorded gaze direction and head-centered field of view. Thirteen additional infants wore a motion-tracker that recorded head orientation. Compared with walkers, crawlers’ field of view contained less walls and more floor. Walkers directed gaze straight ahead at caregivers, whereas crawlers looked down at the floor. Crawlers obtained visual information about targets at higher elevations—caregivers and toys—by craning their heads upward and sitting up to bring the room into view. Findings indicate that visual experiences are intimately tied to infants’ posture. PMID:24341362

Three-dimensional analysis of the cranio-cervico-mandibular complex during piano performance.

PubMed

Clemente, M; Lourenço, S; Coimbra, D; Silva, A; Gabriel, J; Pinho, Jc

2014-09-01

Piano players, as well as other musicians, spend a long time training to achieve the best results, sometimes adopting unnatural body positions that may cause musculoskeletal pain. This paper presents the preliminary results of a study targeting the analysis of the head and cervical postures of 17 piano players during musical performance. It was found, as a common feature, that the players tilt the head to the right and forward towards the score and keyboard. Players who know the score by heart tend to move their heads more compared to the ones who have to keep their eyes on the score.

Postural stability changes during large vertical diplopia induced by prism wear in normal subjects.

PubMed

Matsuo, Toshihiko; Yamasaki, Hanako; Yasuhara, Hirotaka; Hasebe, Kayoko

2013-01-01

To test the effect of double vision on postural stability, we measured postural stability by electric stabilometry before prism-wearing and immediately, 15, 30, and 60min after continuous prism-wearing with 6 prism diopters in total (a 3-prism-diopter prism placed with the base up in front of one eye and with the base down in front of the other eye) in 20 normal adult individuals with their eyes open or closed. Changes in stabilometric parameters in the time course of 60min were analyzed statistically by repeated-measure analysis of variance. When subjectsｾ eyes were closed, the total linear length (cm) and the unit-time length (cm/sec) of the sway path were significantly shortened during the 60-minute prism-wearing (p＜0.05). No significant change was noted in any stabilometric parameters obtained with the eyes open during the time course. In conclusion, postural stability did not change with the eyes open in the condition of large vertical diplopia, induced by prism-wearing for 60min, while the stability became better when measured with the eyes closed. A postural control mechanism other than that derived from visual input might be reinforced under abnormal visual input such as non-fusionable diplopia.

Fear of falling and postural reactivity in patients with glaucoma.

PubMed

Daga, Fábio B; Diniz-Filho, Alberto; Boer, Erwin R; Gracitelli, Carolina P B; Abe, Ricardo Y; Medeiros, Felipe A

2017-01-01

To investigate the relationship between postural metrics obtained by dynamic visual stimulation in a virtual reality environment and the presence of fear of falling in glaucoma patients. This cross-sectional study included 35 glaucoma patients and 26 controls that underwent evaluation of postural balance by a force platform during presentation of static and dynamic visual stimuli with head-mounted goggles (Oculus Rift). In dynamic condition, a peripheral translational stimulus was used to induce vection and assess postural reactivity. Standard deviations of torque moments (SDTM) were calculated as indicative of postural stability. Fear of falling was assessed by a standardized questionnaire. The relationship between a summary score of fear of falling and postural metrics was investigated using linear regression models, adjusting for potentially confounding factors. Subjects with glaucoma reported greater fear of falling compared to controls (-0.21 vs. 0.27; P = 0.039). In glaucoma patients, postural metrics during dynamic visual stimulus were more associated with fear of falling (R2 = 18.8%; P = 0.001) than static (R2 = 3.0%; P = 0.005) and dark field (R2 = 5.7%; P = 0.007) conditions. In the univariable model, fear of falling was not significantly associated with binocular standard perimetry mean sensitivity (P = 0.855). In the multivariable model, each 1 Nm larger SDTM in anteroposterior direction during dynamic stimulus was associated with a worsening of 0.42 units in the fear of falling questionnaire score (P = 0.001). In glaucoma patients, postural reactivity to a dynamic visual stimulus using a virtual reality environment was more strongly associated with fear of falling than visual field testing and traditional balance assessment.

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

PubMed

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.

Fear of falling and postural reactivity in patients with glaucoma

PubMed Central

Daga, Fábio B.; Diniz-Filho, Alberto; Boer, Erwin R.; Gracitelli, Carolina P. B.; Abe, Ricardo Y.; Medeiros, Felipe A.

2017-01-01

Purpose To investigate the relationship between postural metrics obtained by dynamic visual stimulation in a virtual reality environment and the presence of fear of falling in glaucoma patients. Methods This cross-sectional study included 35 glaucoma patients and 26 controls that underwent evaluation of postural balance by a force platform during presentation of static and dynamic visual stimuli with head-mounted goggles (Oculus Rift). In dynamic condition, a peripheral translational stimulus was used to induce vection and assess postural reactivity. Standard deviations of torque moments (SDTM) were calculated as indicative of postural stability. Fear of falling was assessed by a standardized questionnaire. The relationship between a summary score of fear of falling and postural metrics was investigated using linear regression models, adjusting for potentially confounding factors. Results Subjects with glaucoma reported greater fear of falling compared to controls (-0.21 vs. 0.27; P = 0.039). In glaucoma patients, postural metrics during dynamic visual stimulus were more associated with fear of falling (R2 = 18.8%; P = 0.001) than static (R2 = 3.0%; P = 0.005) and dark field (R2 = 5.7%; P = 0.007) conditions. In the univariable model, fear of falling was not significantly associated with binocular standard perimetry mean sensitivity (P = 0.855). In the multivariable model, each 1 Nm larger SDTM in anteroposterior direction during dynamic stimulus was associated with a worsening of 0.42 units in the fear of falling questionnaire score (P = 0.001). Conclusion In glaucoma patients, postural reactivity to a dynamic visual stimulus using a virtual reality environment was more strongly associated with fear of falling than visual field testing and traditional balance assessment. PMID:29211742

Evaluation of biofeedback seat insert for improving active sitting posture in children with cerebral palsy. A clinical report.

PubMed

Bertoti, D B; Gross, A L

1988-07-01

Biofeedback devices have been used successfully to improve head control and symmetrical standing in children with cerebral palsy. This clinical report describes a biofeedback seat insert developed to improve erect sitting posture in children with cerebral palsy who have inadequate trunk control. The seat insert is easily placed against the back of any seating device. A momentary-contact pressure switch on the seat insert is activated when the child exerts pressure on it by extending his trunk. The pressure switch then activates a videocassette recorder or can be adapted to activate a television or radio. Five children with spastic cerebral palsy participated in this evaluation of the biofeedback seat insert. The results of this evaluation show that the children used the biofeedback seat insert effectively to actively improve their sitting posture by voluntarily extending their trunk against the pressure switch. The biofeedback seat insert offers physical therapists a valuable therapeutic training tool to encourage carry-over of improved sitting posture away from the clinical setting for children with cerebral palsy.

A comparison of the postures assumed when using laptop computers and desktop computers.

PubMed

Straker, L; Jones, K J; Miller, J

1997-08-01

This study evaluated the postural implications of using a laptop computer. Laptop computer screens and keyboards are joined, and are therefore unable to be adjusted separately in terms of screen height and distance, and keyboard height and distance. The posture required for their use is likely to be constrained, as little adjustment can be made for the anthropometric differences of users. In addition to the postural constraints, the study looked at discomfort levels and performance when using laptops as compared with desktops. Statistical analysis showed significantly greater neck flexion and head tilt with laptop use. The other body angles measured (trunk, shoulder, elbow, wrist, and scapula and neck protraction/retraction) showed no statistical differences. The average discomfort experienced after using the laptop for 20 min, although appearing greater than the discomfort experienced after using the desktop, was not significantly greater. When using the laptop, subjects tended to perform better than when using the desktop, though not significantly so. Possible reasons for the results are discussed and implications of the findings outlined.

Absence of Rotation Perception during Warm Water Caloric Irrigation in Some Seniors with Postural Instability.

PubMed

Chiarovano, Elodie; Vidal, Pierre-Paul; Magnani, Christophe; Lamas, Georges; Curthoys, Ian S; de Waele, Catherine

2016-01-01

Falls in seniors are a major public health problem. Falls lead to fear of falling, reduced mobility, and decreased quality of life. Vestibular dysfunction is one of the fall risk factors. The relationship between objective measures of vestibular responses and age has been studied. However, the effects of age on vestibular perception during caloric stimulation have not been studied. Twenty senior subjects were included in the study, and separated in two groups: 10 seniors reporting postural instability (PI) and exhibiting absence of vestibular perception when they tested with caloric stimulation and 10 sex- and age-matched seniors with no such problems (controls). We assessed vestibular perception on a binary rating scale during the warm irrigation of the caloric test. The function of the various vestibular receptors was assessed using video head impulse test (vHIT), caloric tests, and cervical and ocular vestibular-evoked myogenic potentials. The Equitest was used to evaluate balance. No horizontal canal dysfunction assessed using both caloric test and vHIT was detected in either group. No significant difference was detected between PI and control groups for the peak SPV of caloric-induced ocular nystagmus or for the HVOR gain. All the controls perceived rotation when the maximal SPV during warm irrigation was equal to or ≥15°/s. None of the subjects in the PI group perceived rotation even while the peak SPV exceeded 15°/s, providing objective evidence of normal peripheral horizontal canal function. All the PI group had abnormal Equitest results, particularly in the two last conditions. These investigations show for the first time that vestibular perception can be absent during a caloric test despite normal horizontal canal function. We call this as dissociation vestibular neglect. Patients with poor vestibular perception may not be aware of postural perturbations and so will not correct for them. Thus, falls in the elderly may result, among other factors, from a vestibular neglect due to an inappropriate central processing of normal vestibular peripheral inputs. That is, failure to perceive rotation during caloric testing when the SPV is >15°/s, should prompt the clinician to envisage preventive actions to avoid future falls such as rehabilitation.

A primitive study on unsupervised anomaly detection with an autoencoder in emergency head CT volumes

NASA Astrophysics Data System (ADS)

Sato, Daisuke; Hanaoka, Shouhei; Nomura, Yukihiro; Takenaga, Tomomi; Miki, Soichiro; Yoshikawa, Takeharu; Hayashi, Naoto; Abe, Osamu

2018-02-01

Purpose: The target disorders of emergency head CT are wide-ranging. Therefore, people working in an emergency department desire a computer-aided detection system for general disorders. In this study, we proposed an unsupervised anomaly detection method in emergency head CT using an autoencoder and evaluated the anomaly detection performance of our method in emergency head CT. Methods: We used a 3D convolutional autoencoder (3D-CAE), which contains 11 layers in the convolution block and 6 layers in the deconvolution block. In the training phase, we trained the 3D-CAE using 10,000 3D patches extracted from 50 normal cases. In the test phase, we calculated abnormalities of each voxel in 38 emergency head CT volumes (22 abnormal cases and 16 normal cases) for evaluation and evaluated the likelihood of lesion existence. Results: Our method achieved a sensitivity of 68% and a specificity of 88%, with an area under the curve of the receiver operating characteristic curve of 0.87. It shows that this method has a moderate accuracy to distinguish normal CT cases to abnormal ones. Conclusion: Our method has potentialities for anomaly detection in emergency head CT.

Effects of Bed Rest on Conduction Velocity of the Triceps Surae Stretch Reflex and Postural Control

NASA Technical Reports Server (NTRS)

Reschke, M. F.; Wood, S. J.; Cerisano, J. M.; Kofman, I. S.; Fisher, E. A.; Esteves, J. T.; Taylor, L. C.; DeDios, Y. E.; Harm, D. L.

2011-01-01

Despite rigorous exercise and nutritional management during space missions, astronauts returning from microgravity exhibit neuromuscular deficits and a significant loss in muscle mass in the postural muscles of the lower leg. Similar changes in the postural muscles occur in subjects participating in long-duration bed rest studies. These adaptive muscle changes manifest as a reduction in reflex conduction velocity during head-down bed rest. Because the stretch reflex encompasses both the peripheral (muscle spindle and nerve axon) and central (spinal synapse) components involved in adaptation to calf muscle unloading, it may be used to provide feedback on the general condition of neuromuscular function, and might be used to evaluate the effectiveness of countermeasures aimed at preserving muscle mass and function during periods of unloading. Stretch reflexes were measured on 18 control subjects who spent 60 to 90 days in continuous 6 deg head-down bed rest. Using a motorized system capable of rotating the foot around the ankle joint (dorsiflexion) through an angle of 10 degrees at a peak velocity of about 250 deg/sec, a stretch reflex was recorded from the subject's left triceps surae muscle group. Using surface electromyography, about 300 reflex responses were obtained and ensemble-averaged on 3 separate days before bed rest, 3 to 4 times in bed, and 3 times after bed rest. The averaged responses for each test day were examined for reflex latency and conduction velocity (CV) across gender. Computerized posturography was also conducted on these same subjects before and after bed rest as part of the standard measures. Peak-to-peak sway was measured during Sensory Organization Tests (SOTs) to evaluate changes in the ability to effectively use or suppress visual, vestibular, and proprioceptive information for postural control. Although no gender differences were found, a significant increase in reflex latency and a significant decrease in CV were observed during the bed rest period, with a return to baseline 3 to 5 days after bed rest, depending on the duration of bed rest. In addition, a relationship between CV and loss of muscle strength in the lower leg was observed post bed rest for most subjects. Immediately post-bed rest, most subjects showed decreased performance on SOTs, with the greater decrements on sway-referenced support and head movement conditions. Post-bed rest decrements were less than typically observed following spaceflight. Decrements in postural control and the stretch reflex can be primarily attributed to the unloading mechanisms this ground-based analog provides. The stretch reflex is a concise test measurement that can be obtained during the head-down phase of bed rest, as it does not interfere with the bed rest paradigm. This makes it an ideal tool that can detect, early on, whether a countermeasure is successful in preserving muscle function.

Rationale, principles and experimental evaluation of the concept of soft stabilization.

PubMed

Mulholland, Robert C; Sengupta, Dilip K

2002-10-01

The apparent clinical success of spinal stabilization methods that restrict rather than abolish movement in relieving mechanical back pain indicates that the concept of the aetiology of back pain should be reviewed. Further understanding of how degeneration affects disc biomechanics, and an understanding of how current soft stabilization systems alters them, may allow us to define more precisely what are the essential requirements of an ideal soft stabilization system. It appears that abnormal patterns of loading rather than abnormal movement are the reason that disc degeneration causes back pain in some patients. Abnormal load transmission is the principal cause of pain in osteoarthritic joints, and both osteotomy and, indeed, joint replacement succeed because they alter the load transmission across the joint. This concept is supported by the fact that abnormal patterns of stress distribution measured across the disc correlate with painful discs on discography. Clinically, it is often noted that back pain is primarily related to position or posture, rather than movement of the lumbar spine. Clinical success after solid fusion is unpredictable because it does not necessarily prevent painful loading across the disc, and also it may interfere with maintenance of sagittal balance in varying postures. The Graf ligament restricted flexion, and was modestly successful. It unfortunately increased the load over the posterior annulus. The Dynesys system reduces movement both in flexion and extension, and appears to be more successful. However, often it also unloads the disc to a degree that is unpredictable. The authors believe that this unloading of the disc is an important feature of a flexible stabilization system. A new a design of a flexible stabilization system has recently been described in an in vitro study, which unloads the disc by introduction of a load-sharing fulcrum near the axis of movement together with an elastic posterior ligament. This design produces maximal unloading of the disc, whilst allowing a restricted range of movement, which serves the important purpose of allowing the patient to maintain sagittal balance in varying postures.

Interest of active posturography to detect age-related and early Parkinson's disease-related impairments in mediolateral postural control.

PubMed

Bonnet, Cédrick T; Delval, Arnaud; Defebvre, Luc

2014-11-15

Patients with Parkinson's disease display impairments of postural control most particularly in active, challenging conditions. The objective of the present study was to analyze early signs of disease-related and also age-related impairments in mediolateral body extension and postural control. Fifty-five participants (18 Hoehn and Yahr stage 2 patients in the off-drug condition, 18 healthy elderly control subjects, and 19 young adults) were included in the study. The participants performed a quiet stance task and two active tasks that analyzed the performance in mediolateral body motion: a limit of stability and a rhythmic weight shift task. As expected, the patients displayed significantly lower and slower body displacement (head, neck, lower back, center of pressure) than elderly control subjects when performing the two body excursion tasks. However, the behavioral variability in both tasks was similar between the groups. Under these active conditions, the patients showed significantly lower contribution of the hip postural control mechanisms compared with the elderly control subjects. Overall, the patients seemed to lower their performance in order to prevent a mediolateral postural instability. However, these patients, at an early stage of their disease, were not unstable in quiet stance. Complementarily, elderly control subjects displayed slower body performance than young adults, which therefore showed an additional age-related impairment in mediolateral postural control. Overall, the study illustrated markers of age-related and Parkinson's disease impairments in mediolateral postural control that may constrain everyday activities in elderly adults and even more in patients with Parkinson's disease. Copyright © 2014 the American Physiological Society.

Body language: The interplay between positional behavior and gestural signaling in the genus Pan and its implications for language evolution.

PubMed

Smith, Lindsey W; Delgado, Roberto A

2015-08-01

The gestural repertoires of bonobos and chimpanzees are well documented, but the relationship between gestural signaling and positional behavior (i.e., body postures and locomotion) has yet to be explored. Given that one theory for language evolution attributes the emergence of increased gestural communication to habitual bipedality, this relationship is important to investigate. In this study, we examined the interplay between gestures, body postures, and locomotion in four captive groups of bonobos and chimpanzees using ad libitum and focal video data. We recorded 43 distinct manual (involving upper limbs and/or hands) and bodily (involving postures, locomotion, head, lower limbs, or feet) gestures. In both species, actors used manual and bodily gestures significantly more when recipients were attentive to them, suggesting these movements are intentionally communicative. Adults of both species spent less than 1.0% of their observation time in bipedal postures or locomotion, yet 14.0% of all bonobo gestures and 14.7% of all chimpanzee gestures were produced when subjects were engaged in bipedal postures or locomotion. Among both bonobo groups and one chimpanzee group, these were mainly manual gestures produced by infants and juvenile females. Among the other chimpanzee group, however, these were mainly bodily gestures produced by adult males in which bipedal posture and locomotion were incorporated into communicative displays. Overall, our findings reveal that bipedality did not prompt an increase in manual gesturing in these study groups. Rather, body postures and locomotion are intimately tied to many gestures and certain modes of locomotion can be used as gestures themselves. © 2015 Wiley Periodicals, Inc.

Body posture changes in women with migraine with or without temporomandibular disorders

PubMed Central

Ferreira, Mariana C.; Bevilaqua-Grossi, Débora; Dach, Fabíola É.; Speciali, José G.; Gonçalves, Maria C.; Chaves, Thais C.

2014-01-01

Background Migraine and temporomandibular disorders (TMDs) are reported to be associated. However, there are no reports on the association among migraines, TMDs and changes in body posture. Objectives To assess changes in body posture in women suffering migraines with or without TMD compared with a control group. Method Sixty-six women with a mean age of 18 to 45 years participated in this study. The groups were composed of 22 volunteers with migraine and TMD (MTMD), 22 volunteers with migraines without TMD (MG) and 22 women in the control group (CG). Static posture was assessed by photogrammetry, and 19 angles were measured. Results Postural asymmetry was observed in the face for 4 angles measured on the frontal plane in the MG group and for 4 angles of the trunk in the MG and MTMD groups with respect to CG. However, for comparisons between MTMD and CG, clinical relevance was identified for two angles of the sagittal plane (Cervical and Lumbar Lordosis, Effect Size - ES - moderate: 0.53 and 0.60). For comparisons between the MG and CG, the clinical relevance/potential was verified for three angles with moderate ES (ES>0.42). The clinical relevance when comparing MTMD and CG was identified for four angles of facial symmetry head inclination (ES>0.54) and for two angles between MG and CG (ES>0.48). Conclusion The results demonstrated the presence of postural changes compared with a control group in women with migraines with or without TMD, and there were similar clinically relevant postural changes among the patients with migraines with and without TMD. PMID:24675909

Body posture changes in women with migraine with or without temporomandibular disorders.

PubMed

Ferreira, Mariana C; Bevilaqua-Grossi, Débora; Dach, Fabíola E; Speciali, José G; Gonçalves, Maria C; Chaves, Thais C

2014-01-01

Migraine and temporomandibular disorders (TMDs) are reported to be associated. However, there are no reports on the association among migraines, TMDs and changes in body posture. To assess changes in body posture in women suffering migraines with or without TMD compared with a control group. Sixty-six women with a mean age of 18 to 45 years participated in this study. The groups were composed of 22 volunteers with migraine and TMD (MTMD), 22 volunteers with migraines without TMD (MG) and 22 women in the control group (CG). Static posture was assessed by photogrammetry, and 19 angles were measured. Postural asymmetry was observed in the face for 4 angles measured on the frontal plane in the MG group and for 4 angles of the trunk in the MG and MTMD groups with respect to CG. However, for comparisons between MTMD and CG, clinical relevance was identified for two angles of the sagittal plane (Cervical and Lumbar Lordosis, Effect Size - ES - moderate: 0.53 and 0.60). For comparisons between the MG and CG, the clinical relevance/potential was verified for three angles with moderate ES (ES>0.42). The clinical relevance when comparing MTMD and CG was identified for four angles of facial symmetry head inclination (ES>0.54) and for two angles between MG and CG (ES>0.48). The results demonstrated the presence of postural changes compared with a control group in women with migraines with or without TMD, and there were similar clinically relevant postural changes among the patients with migraines with and without TMD.

Are we simplifying balance evaluation in adolescent idiopathic scoliosis?

PubMed

Pasha, Saba; Baldwin, Keith

2018-01-01

Clinical evaluation of the postural balance in adolescent idiopathic scoliosis has been measured by sagittal vertical axis and frontal balance. The impact of the scoliotic deformity in three planes on balance has not been fully investigated. 47 right thoracic and left lumbar curves adolescent idiopathic scoliosis and 10 non-scoliotic controls were registered prospectively. 13 spinopelvic postural parameters were calculated from the 3-dimantional reconstructions of X-rays. 7 balance variables describing the position and sway of the center of pressure were recorded using a pressure mat. A regression analysis was used to predict sagittal vertical axis and frontal balance from the 7 balance variables. A canonical correlation analysis was performed between all the postural parameters and balance variables and the significant associations between the postural and balance variables were determined. sagittal vertical axis and frontal balance were not significantly associated with the position or sway of the center of pressure (p>0.05). Canonical correlation analysis showed significant associations between the postural variables in the 3 planes and center of pressure position (R 2 =0.81) and sway (R 2 =0.62), p<0.05. Frontal Cobbs, apical rotations, distal kyphosis, pelvic incidence, sacral slope, sagittal vertical axis, and frontal balance contributed to the postural balance in the cohort. The compensatory role of the pelvis and distal kyphosis in sagittal plane was underlined. Multidimensional analyses between the postural and balance variables showed the alignment of the thoracic, lumbar, and pelvis in the 3 planes, in addition to the global head-pelvic position impact on adolescent idiopathic scoliosis balance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Interrelations between orthostatic postural deviations and subjects' age, sex, malocclusion, and specific signs and symptoms of functional pathologies of the temporomandibular system: a preliminary correlation and regression study.

PubMed

Munhoz, Wagner Cesar; Hsing, Wu Tu

2014-07-01

Studies on the relationships between postural deviations and the temporomandibular system (TS) functional health are controversial and inconclusive. This study stems from the hypothesis that such inconclusiveness is due to authors considering functional pathologies of the TS (FPTS) as a whole, without taking into account subjects' specific FPTS signs and symptoms. Based on the author and collaborators' previous studies, the present study analyzed data on body posture from a sample of 50 subjects with (30) and without (20) FPTS. Correlation analyses were applied, taking as independent variables age, sex, Helkimo anamnestic, occlusal, and dysfunction indices, as well as FPTS specific signs and symptoms. Postural assessments of the head, cervical spine, shoulders, lumbar spine, and hips were the dependent variables. Linear regression equations were built that proved to partially predict the presence and magnitude of body posture deviations by drawing on subjects' characteristics and specific FPTS symptoms. Determination coefficients for these equations ranged from 0.082 to 0.199 in the univariate, and from 0.121 to 0.502 in the multivariate regression analyses. Results show that factors intrinsic to the subjects or the TS may potentially interfere in results of studies that analyze relationships between FPTS and body posture. Furthermore, a trend to specificity was found, e.g. the degree of cervical lordosis was found to correlate to age and FPTS degree of severity, suggesting that some TS pathological features, or malocclusion, age or sex, may be more strongly correlated than others with specific posture patterns.

Human Body 3D Posture Estimation Using Significant Points and Two Cameras

PubMed Central

Juang, Chia-Feng; Chen, Teng-Chang; Du, Wei-Chin

2014-01-01

This paper proposes a three-dimensional (3D) human posture estimation system that locates 3D significant body points based on 2D body contours extracted from two cameras without using any depth sensors. The 3D significant body points that are located by this system include the head, the center of the body, the tips of the feet, the tips of the hands, the elbows, and the knees. First, a linear support vector machine- (SVM-) based segmentation method is proposed to distinguish the human body from the background in red, green, and blue (RGB) color space. The SVM-based segmentation method uses not only normalized color differences but also included angle between pixels in the current frame and the background in order to reduce shadow influence. After segmentation, 2D significant points in each of the two extracted images are located. A significant point volume matching (SPVM) method is then proposed to reconstruct the 3D significant body point locations by using 2D posture estimation results. Experimental results show that the proposed SVM-based segmentation method shows better performance than other gray level- and RGB-based segmentation approaches. This paper also shows the effectiveness of the 3D posture estimation results in different postures. PMID:24883422

Control of vertical posture while elevating one foot to avoid a real or virtual obstacle.

PubMed

Ida, Hirofumi; Mohapatra, Sambit; Aruin, Alexander

2017-06-01

The purpose of this study is to investigate the control of vertical posture during obstacle avoidance in a real versus a virtual reality (VR) environment. Ten healthy participants stood upright and lifted one leg to avoid colliding with a real obstacle sliding on the floor toward a participant and with its virtual image. Virtual obstacles were delivered by a head mounted display (HMD) or a 3D projector. The acceleration of the foot, center of pressure, and electrical activity of the leg and trunk muscles were measured and analyzed during the time intervals typical for early postural adjustments (EPAs), anticipatory postural adjustments (APAs), and compensatory postural adjustments (CPAs). The results showed that the peak acceleration of foot elevation in the HMD condition decreased significantly when compared with that of the real and 3D projector conditions. Reduced activity of the leg and trunk muscles was seen when dealing with virtual obstacles (HMD and 3D projector) as compared with that seen when dealing with real obstacles. These effects were more pronounced during APAs and CPAs. The onsets of muscle activities in the supporting limb were seen during EPAs and APAs. The observed modulation of muscle activity and altered patterns of movement seen while avoiding a virtual obstacle should be considered when designing virtual rehabilitation protocols.

Resolving Sensory Conflict: the Effect of Muscle Vibration on Postural Stability

NASA Technical Reports Server (NTRS)

Layne, Charles S.

1991-01-01

The otolith-tilt reinterpretation hypothesis (OTTR) proposes that the central nervous system adapts to weightlessness by reinterpreting all otolith input as linear motion. While interpreting otolith input exclusively as linear motion is functionally useful in space, it is maladaptive upon return to Earth. Astronauts have reported experiencing illusory sensations during head movement which contributes to postural instability. The effect is assessed of muscle vibration in combination with a variety of sensory conflicts on postural equilibrium. The equilibrium of six healthy subjects was tested using the EquiTest sensory test protocol, with and without the confounding influence of triceps surea vibration. The data were analyzed with repeated measures with vibration, vision status, and platform status as independent variables. All main effects and an interaction between the presence of vision and platform sway referencing were found to be significant. Overall, a 4.5 pct. decrease in postural stability was observed with vibration. The trend of the difference scores between conditions with and without vibration suggests that vibration is most destabilizing when the triceps surea is able to change length during postural sway (i.e., conditions with a fixed support surface). The impact of sway referencing vision was virtually identical to that of eye closure, providing compelling evidence that sway referencing 'nulls out' useful cues about subject sway.

School furniture and work surface lighting impacts on the body posture of Paraíba's public school students.

PubMed

da Silva, Luiz Bueno; Coutinho, Antonio Souto; da Costa Eulálio, Eliza Juliana; Soares, Elaine Victor Gonçalves

2012-01-01

The main objective of this study is to evaluate the impact of school furniture and work surface lighting on the body posture of public Middle School students from Paraíba (Brazil). The survey was carried out in two public schools and the target population for the study included 8th grade groups involving a total of 31 students. Brazilian standards for lighting levels, the CEBRACE standards for furniture measurements and the Postural Assessment Software (SAPO) for the postural misalignment assay were adopted for the measurements comparison. The statistic analysis includes analyses of parametric and non-parametric correlations. The results show that the students' most affected parts of the body were the spine, the regions of the knees and head and neck, with 90% of the total number of students presenting postural misalignment. The lighting levels were usually found below 300 lux, below recommended levels. The statistic analysis show that the more adequate the furniture seems to be to the user, the less the user will complain of pain. Such results indicate the need of investments in more suitable school furniture and structural reforms aimed at improving the lighting in the classrooms, which could fulfill the students' profile and reduce their complaints.

Neural control and precision of flight muscle activation in Drosophila.

PubMed

Lehmann, Fritz-Olaf; Bartussek, Jan

2017-01-01

Precision of motor commands is highly relevant in a large context of various locomotor behaviors, including stabilization of body posture, heading control and directed escape responses. While posture stability and heading control in walking and swimming animals benefit from high friction via ground reaction forces and elevated viscosity of water, respectively, flying animals have to cope with comparatively little aerodynamic friction on body and wings. Although low frictional damping in flight is the key to the extraordinary aerial performance and agility of flying birds, bats and insects, it challenges these animals with extraordinary demands on sensory integration and motor precision. Our review focuses on the dynamic precision with which Drosophila activates its flight muscular system during maneuvering flight, considering relevant studies on neural and muscular mechanisms of thoracic propulsion. In particular, we tackle the precision with which flies adjust power output of asynchronous power muscles and synchronous flight control muscles by monitoring muscle calcium and spike timing within the stroke cycle. A substantial proportion of the review is engaged in the significance of visual and proprioceptive feedback loops for wing motion control including sensory integration at the cellular level. We highlight that sensory feedback is the basis for precise heading control and body stability in flies.

Multisensory integration in early vestibular processing in mice: the encoding of passive vs. active motion

PubMed Central

Medrea, Ioana

2013-01-01

The mouse has become an important model system for studying the cellular basis of learning and coding of heading by the vestibular system. Here we recorded from single neurons in the vestibular nuclei to understand how vestibular pathways encode self-motion under natural conditions, during which proprioceptive and motor-related signals as well as vestibular inputs provide feedback about an animal's movement through the world. We recorded neuronal responses in alert behaving mice focusing on a group of neurons, termed vestibular-only cells, that are known to control posture and project to higher-order centers. We found that the majority (70%, n = 21/30) of neurons were bimodal, in that they responded robustly to passive stimulation of proprioceptors as well as passive stimulation of the vestibular system. Additionally, the linear summation of a given neuron's vestibular and neck sensitivities predicted well its responses when both stimuli were applied simultaneously. In contrast, neuronal responses were suppressed when the same motion was actively generated, with the one striking exception that the activity of bimodal neurons similarly and robustly encoded head on body position in all conditions. Our results show that proprioceptive and motor-related signals are combined with vestibular information at the first central stage of vestibular processing in mice. We suggest that these results have important implications for understanding the multisensory integration underlying accurate postural control and the neural representation of directional heading in the head direction cell network of mice. PMID:24089394

Foot posture, foot function and low back pain: the Framingham Foot Study

PubMed Central

Menz, Hylton B.; Dufour, Alyssa B.; Riskowski, Jody L.; Hillstrom, Howard J.

2013-01-01

Objective. Abnormal foot posture and function have been proposed as possible risk factors for low back pain, but this has not been examined in detail. The objective of this study was to explore the associations of foot posture and foot function with low back pain in 1930 members of the Framingham Study (2002–05). Methods. Low back pain, aching or stiffness on most days was documented on a body chart. Foot posture was categorized as normal, planus or cavus using static weight-bearing measurements of the arch index. Foot function was categorized as normal, pronated or supinated using the centre of pressure excursion index derived from dynamic foot pressure measurements. Sex-specific multivariate logistic regression models were used to examine the associations of foot posture, foot function and asymmetry with low back pain, adjusting for confounding variables. Results. Foot posture showed no association with low back pain. However, pronated foot function was associated with low back pain in women [odds ratio (OR) = 1.51, 95% CI 1.1, 2.07, P = 0.011] and this remained significant after adjusting for age, weight, smoking and depressive symptoms (OR = 1.48, 95% CI 1.07, 2.05, P = 0.018). Conclusion. These findings suggest that pronated foot function may contribute to low back symptoms in women. Interventions that modify foot function, such as orthoses, may therefore have a role in the prevention and treatment of low back pain. PMID:24049103

Global body posture and plantar pressure distribution in individuals with and without temporomandibular disorder: a preliminary study.

PubMed

Souza, Juliana A; Pasinato, Fernanda; Corrêa, Eliane C R; da Silva, Ana Maria T

2014-01-01

The aim of this study was to evaluate body posture and the distribution of plantar pressure at physiologic rest of the mandible and during maximal intercuspal positions in subjects with and without temporomandibular disorder (TMD). Fifty-one subjects were assessed by the Diagnostic Criteria for Research on Temporomandibular Disorders and divided into a symptomatic group (21) and an asymptomatic group (30). Postural analysis for both groups was conducted using photogrammetry (SAPo version 0.68; University of São Paulo, São Paulo, Brazil). The distribution of plantar pressures was evaluated by means of baropodometry (Footwork software), at physiologic rest and maximal intercuspal positions. Of 18 angular measurements, 3 (17%) were statistically different between the groups in photogrammetric evaluation. The symptomatic group showed more pronounced cervical distance (P = .0002), valgus of the right calcaneus (P = .0122), and lower pelvic tilt (P = .0124). The baropodometry results showed the TMD subjects presented significantly higher rearfoot and lower forefoot distribution than those in the asymptomatic group. No differences were verified in maximal intercuspal position in the between-group analysis and between the 2 mandibular positions in the within-group analysis. Subjects with and without TMD presented with global body posture misalignment. Postural changes were more pronounced in the subjects with TMD. In addition, symptomatic subjects presented with abnormal plantar pressure distribution, suggesting that TMD may have an influence on the postural system. Copyright © 2014 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.

Nonspherical femoral head shape (pistol grip deformity), neck shaft angle, and risk of hip osteoarthritis: a case-control study.

PubMed

Doherty, Michael; Courtney, Philip; Doherty, Sally; Jenkins, Wendy; Maciewicz, Rose A; Muir, Kenneth; Zhang, Weiya

2008-10-01

To determine whether 2-dimensional measures of femoral head shape and angle are associated with hip osteoarthritis (OA). We compared cases with symptomatic radiographic hip OA with asymptomatic controls with no radiographic hip OA. On anteroposterior pelvis radiographs, we measured "pistol grip deformity" for each hip (visually categorized as nonspherical, indeterminate, or spherical), the femoral head-to-femoral neck ratio as an interval measure of femoral head shape, and the femoral neck shaft angle. The relative risk of hip OA associated with each feature was estimated using odds ratios (ORs) and 95% confidence intervals (95% CIs), adjusted for possible confounders using a logistic regression model. Of 1,007 cases, 965 had definite radiographic hip OA; of 1,123 controls, 1,111 had no radiographic OA. The prevalence of pistol grip deformity in at least 1 hip was 3.61% in controls and 17.71% in cases (OR 6.95 [95% CI 4.64-10.41]), and the prevalence of abnormal femoral head-to-femoral neck ratio in at least 1 hip was 3.70% in controls and 24.27% in cases (OR 12.08 [95% CI 8.05-18.15]). The risk of hip OA increased as the femoral head-to-femoral neck ratio decreased (P for trend<0.001) and with each extreme of neck shaft angle (P<0.05). In cases with unilateral hip OA, the prevalence of abnormal femoral head-to-femoral neck ratio in the unaffected hip was 2 times greater than that in controls (OR 1.82 [95% CI 1.07-3.07]); in contrast, an abnormally low, but not abnormally high, neck shaft angle was more common in unaffected hips than in controls (OR 1.79 [95% CI 1.03-3.14]). Our findings indicate that pistol grip deformity is associated with hip OA. The increased prevalence of pistol grip deformity and an abnormally low neck shaft angle in unaffected hips of cases with unilateral OA suggests that they are risk factors for development of hip OA. However, both a nonspherical head shape and an increase in neck shaft angle may occur as a consequence of OA.

Temporary cerebral revascularization using a radial artery in the hand-eyeshade posture: technical note.

PubMed

Hiramoto, Jun; Tanaka, Yuichiro

2014-06-17

Kamiyama introduced a unique method of temporary cerebral revascularization using a radial artery graft (RAG) in his technical review. We tried original method with Sugita frame, and pointed out some disadvantages that include to avoid taking instruments or hands in and out, stability of hands, and unrestricted usage of brain retractors during temporary bypass between radial artery and M2 potion of middle cerebral artery (RA-M2 bypass). To solve those disadvantages, especially for Sugita head frame users, we here present a modified Kamiyama's method of temporary cerebral revascularization with the forearm elevated over the face like as hand-eyeshade posture.

Added Value of Including Entire Brain on Body Imaging With FDG PET/MRI.

PubMed

Franceschi, Ana M; Matthews, Robert; Bangiyev, Lev; Relan, Nand; Chaudhry, Ammar; Franceschi, Dinko

2018-05-24

FDG PET/MRI examination of the body is routinely performed from the skull base to the mid thigh. Many types of brain abnormalities potentially could be detected on PET/MRI if the head was included. The objective of this study was therefore to identify and characterize brain findings incidentally detected on PET/MRI of the body with the head included. We retrospectively identified 269 patients with FDG PET/MRI whole-body scans that included the head. PET/MR images of the brain were reviewed by a nuclear medicine physician and neuroradiologist, first individually and then concurrently. Both PET and MRI findings were identified, including abnormal FDG uptake, standardized uptake value, lesion size, and MRI signal characteristics. For each patient, relevant medical history and prior imaging were reviewed. Of the 269 subjects, 173 were women and 96 were men (mean age, 57.4 years). Only the initial PET/MR image of each patient was reviewed. A total of 37 of the 269 patients (13.8%) had abnormal brain findings noted on the PET/MRI whole-body scan. Sixteen patients (5.9%) had vascular disease, nine patients (3.3%) had posttherapy changes, and two (0.7%) had benign cystic lesions in the brain. Twelve patients (4.5%) had serious nonvascular brain abnormalities, including cerebral metastasis in five patients and pituitary adenomas in two patients. Only nine subjects (3.3%) had a new neurologic or cognitive symptom suggestive of a brain abnormality. Routine body imaging with FDG PET/MRI of the area from the skull base to the mid thigh may miss important brain abnormalities when the head is not included. The additional brain abnormalities identified on whole-body imaging may provide added clinical value to the management of oncology patients.

NASA's Functional Task Test: Effects of Spaceflight and Six Degree Head-Down Bedrest on Dynamic Postural Stability

NASA Technical Reports Server (NTRS)

Taylor, L. C.; Batson, C. D.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Laurie, S.; Lee, S. M. C.; Miller, C. A.; Mulavara, A. P.; Peters, B. T.;

Effects of head down tilt on episcleral venous pressure in a rabbit model.

PubMed

Lavery, W J; Kiel, J W

2013-06-01

In humans, changing from upright to supine elicits an approximately 10 mmHg increase in cephalic venous pressure caused by the hydrostatic column effect, but episcleral venous pressure (EVP) and intraocular pressure (IOP) rise by only a few mmHg. The dissociation of the small increases in IOP and EVP compared to the larger increase in cephalic venous pressure suggests a regulatory mechanism controlling EVP. The aim of the present study was to determine if the rabbit model is suitable to study the effects of postural changes on EVP despite its short hydrostatic column. In anesthetized rabbits (n = 43), we measured arterial pressure (AP), IOP, and orbital venous pressure (OVP) by direct cannulation; carotid blood flow (BFcar) by transit time ultrasound, heart rate (HR) by digital cardiotachometer, and EVP with a servonull micropressure system. The goal of the protocol was to obtain measurement of supine EVP for ≈10 min, followed by ≈10 min of EVP measurement with the rabbit in a head down tilt. The data were analyzed by paired t-tests and the results reported as the mean ± standard error of the mean. In a separate group of animals (n = 35), aqueous flow was measured by fluorophotometry. This protocol entailed measurement of aqueous flow in the supine position for ≈60 min, followed by ≈60 min of aqueous flow measurement with the rabbit in a head down tilt. From supine to head down tilt, AP and BFcar were unchanged, IOP increased by 2.3 ± 0.4 mmHg (p < 0.001), EVP increased by 2.4 ± 0.4 mmHg (p < 0.001), OVP increased by 2.5 ± 0.2 mmHg (p < 0.001) and HR decreased by 9 ± 3 bpm (p = 0.002). Head down tilt caused no significant change in aqueous flow. Although the hydrostatic column in the rabbit is shorter than humans, the rabbit model permits sufficiently sensitive measurements of the pressures and systemic parameters likely involved in the EVP responses to posture change. The present results indicate directionally similar EVP and IOP responses to tilt as occur in humans and, as in humans, the responses are smaller than would be expected from the change in the hydrostatic column height. Also, as in humans, the model reveals no change in aqueous flow during head down tilt. We conclude the rabbit model is appropriate for studying the mechanisms responsible for the relative immunity of EVP and IOP to posture change. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of microgravity on spatial orientation and posture regulation during Coriolis stimulation.

PubMed

Takahashi, Masahiro; Sekine, Motoki; Ikeda, Takuo; Watanuki, Koichi; Hakuta, Shuzo; Takeoka, Hajime

2004-05-01

To elucidate spatial orientation and posture regulation under conditions of microgravity. Coriolis stimulation was done with five normal subjects on the ground (1 g) and onboard an aircraft (under conditions of microgravity during parabolic flight). Subjects were asked to tilt their heads forward during rotation at speeds of 0, 50, 100 and 150 degrees/s on the ground and 100 degrees/s during flight. Body sway was recorded using a 3D linear accelerometer and eye movements using an infrared charge-coupled device video camera. Flight experiments were performed on 5 consecutive days, and 11-16 parabolic maneuvers were done during each flight. Two subjects boarded each flight and were examined alternately at least five times. Coriolis stimulation at 1 g caused body sway, nystagmus and a movement sensation in accordance with inertial inputs at 1 g. Neither body sway, excepting a minute sway due to the Coriolis force, nor a movement sensation occurred in microgravity, but nystagmus was recorded. Posture, eye movement and sensation at 1 g are controlled with reference to spatial coordinates that represent the external world in the brain. Normal spatial coordinates are not relevant in microgravity because there is no Z-axis, and the posture regulation and sensation that depend on them collapse. The discrepancy in responses between posture and eye movement under conditions of microgravity may be caused by a different constitution of the effectors which adjust posture and gaze.

Captive Bottlenose Dolphins (Tursiops truncatus) Spontaneously Using Water Flow to Manipulate Objects

PubMed Central

Yamamoto, Chisato; Furuta, Keisuke; Taki, Michihiro; Morisaka, Tadamichi

2014-01-01

Several terrestrial animals and delphinids manipulate objects in a tactile manner, using parts of their bodies, such as their mouths or hands. In this paper, we report that bottlenose dolphins (Tursiops truncatus) manipulate objects not by direct bodily contact, but by spontaneous water flow. Three of four dolphins at Suma Aqualife Park performed object manipulation with food. The typical sequence of object manipulation consisted of a three step procedure. First, the dolphins released the object from the sides of their mouths while assuming a head-down posture near the floor. They then manipulated the object around their mouths and caught it. Finally, they ceased to engage in their head-down posture and started to swim. When the dolphins moved the object, they used the water current in the pool or moved their head. These results showed that dolphins manipulate objects using movements that do not directly involve contact between a body part and the object. In the event the dolphins dropped the object on the floor, they lifted it by making water flow in one of three methods: opening and closing their mouths repeatedly, moving their heads lengthwise, or making circular head motions. This result suggests that bottlenose dolphins spontaneously change their environment to manipulate objects. The reason why aquatic animals like dolphins do object manipulation by changing their environment but terrestrial animals do not may be that the viscosity of the aquatic environment is much higher than it is in terrestrial environments. This is the first report thus far of any non-human mammal engaging in object manipulation using several methods to change their environment. PMID:25250625

Sudden Sensorineural Hearing Loss: The Question of Perilymph Fistula.

ERIC Educational Resources Information Center

Backous, Douglas D.; Niparko, John K.

1997-01-01

Perilymph fistula (PLF) is an abnormal communication between the fluid-containing spaces of the inner ear and the air-containing spaces of the temporal bone that can cause hearing loss, tinnitus, aural fullness, vertigo, and postural instability. Diagnosis of PLF and management of those with presumed PLF are discussed. (Contains extensive…

Wii-Based Exercise Program to Improve Physical Fitness, Motor Proficiency and Functional Mobility in Adults with Down Syndrome

ERIC Educational Resources Information Center

Silva, V.; Campos, C.; Sá, A.; Cavadas, M.; Pinto, J.; Simões, P.; Machado, S.; Murillo-Rodríguez, E.; Barbosa-Rocha, N.

2017-01-01

Background: People with Down syndrome (DS) usually display reduced physical fitness (aerobic capacity, muscle strength and abnormal body composition), motor proficiency impairments (balance and postural control) and physical functional limitations. Exergames can be an appealing alternative to enhance exercise engagement and compliance, whilst…

Subtalar neutral position as an offset for a kinematic model of the foot during walking.

PubMed

Houck, Jeff R; Tome, Josh M; Nawoczenski, Deborah A

2008-07-01

The lack of a common reference position when defining foot postures may underestimate the ability to differentiate foot function in subjects with pathology. The effect of using the subtalar neutral (STN) position as an offset for both rearfoot and forefoot through comparison of the kinematic walking patterns of subjects classified as normal (n=7) and abnormally pronated (n=14) foot postures was completed. An Optotrak Motion Analysis System (Northern Digital, Inc.) integrated with Motion Monitor Software (Innovative Sports, Inc.) was used to track three-dimensional movement of the leg, rearfoot and first metatarsal segments. Intrarater reliability of positioning the foot into STN using clinical guidelines was determined for a single rater for 21 subjects. Walking data were subsequently compared before and after an offset was applied to the rearfoot and first metatarsal segments. Repeated measures of foot positioning found the STN position to be highly repeatable (intraclass correlation coefficients>0.9), with peak errors ranging from 1.9 degrees to 4.3 degrees . Utilizing STN as the offset resulted in a significant increase in rearfoot eversion (p=0.019) during early stance, and greater first metatarsal dorsiflexion (p<0.007) across stance in the pronated foot groups that was not observed prior to applying the offset. When applied to subjects with differing foot postures, the selection of a common reference position that is both clinically appropriate and reliable may distinguish kinematic patterns during walking that are consistent with theories of abnormal pronation.

Familial orthostatic tachycardia due to norepinephrine transporter deficiency

NASA Technical Reports Server (NTRS)

Robertson, D.; Flattem, N.; Tellioglu, T.; Carson, R.; Garland, E.; Shannon, J. R.; Jordan, J.; Jacob, G.; Blakely, R. D.; Biaggioni, I.

2001-01-01

Orthostatic intolerance (OI) or postural tachycardia syndrome (POTS) is a syndrome primarily affecting young females, and is characterized by lightheadedness, palpitations, fatigue, altered mentation, and syncope primarily occurring with upright posture and being relieved by lying down. There is typically tachycardia and raised plasma norepinephrine levels on upright posture, but little or no orthostatic hypotension. The pathophysiology of OI is believed to be very heterogeneous. Most studies of the syndrome have focused on abnormalities in norepinephrine release. Here the hypothesis that abnormal norepinephrine transporter (NET) function might contribute to the pathophysiology in some patients with OI was tested. In a proband with significant orthostatic symptoms and tachycardia, disproportionately elevated plasma norepinephrine with standing, impaired systemic, and local clearance of infused tritiated norepinephrine, impaired tyramine responsiveness, and a dissociation between stimulated plasma norepinephrine and DHPG elevation were found. Studies of NET gene structure in the proband revealed a coding mutation that converts a highly conserved transmembrane domain Ala residue to Pro. Analysis of the protein produced by the mutant cDNA in transfected cells demonstrated greater than 98% reduction in activity relative to normal. NE, DHPG/NE, and heart rate correlated with the mutant allele in this family. CONCLUSION: These results represent the first identification of a specific genetic defect in OI and the first disease linked to a coding alteration in a Na+/Cl(-)-dependent neurotransmitter transporter. Identification of this mechanism may facilitate our understanding of genetic causes of OI and lead to the development of more effective therapeutic modalities.

Normal sensorimotor plasticity in complex regional pain syndrome with fixed posture of the hand.

PubMed

Morgante, Francesca; Naro, Antonino; Terranova, Carmen; Russo, Margherita; Rizzo, Vincenzo; Risitano, Giovanni; Girlanda, Paolo; Quartarone, Angelo

2017-01-01

Movement disorders associated with complex regional pain syndrome type I have been a subject of controversy over the last 10 years regarding their nature and pathophysiology, with an intense debate about the functional (psychogenic) nature of this disorder. The aim of this study was to test sensorimotor plasticity and cortical excitability in patients with complex regional pain syndrome type I who developed a fixed posture of the hand. Ten patients with complex regional pain syndrome type I in the right upper limb and a fixed posture of the hand (disease duration less than 24 months) and 10 age-matched healthy subjects were enrolled. The following parameters of corticospinal excitability were recorded from the abductor pollicis brevis muscle of both hands by transcranial magnetic stimulation: resting and active motor thresholds, short-interval intracortical inhibition and facilitation, cortical silent period, and short- and long-latency afferent inhibition. Sensorimotor plasticity was tested using the paired associative stimulation protocol. Short-interval intracortical inhibition and long-latency afferent inhibition were reduced only in the affected right hand of patients compared with control subjects. Sensorimotor plasticity was comparable to normal subjects, with a preserved topographic specificity. Our data support the view that motor disorder in complex regional pain syndrome type I is not associated with abnormal sensorimotor plasticity, and it shares pathophysiological abnormalities with functional (psychogenic) dystonia rather than with idiopathic dystonia. © 2016 International Parkinson and Movement Disorder Society. © 2016 International Parkinson and Movement Disorder Society.

"Loss of breath" as a cause of postoperative hypoxia and bradycardia in children submitted to tonsillectomy.

PubMed

Moro, Eduardo Toshiyuki; Goulart, Alexandre Palmeira

2015-01-01

the "shortness of breath" or "breathing interruption" crisis can be considered a cause of hypoxia in childhood. It is characterized by the presence of a triggering factor followed by weeping and apnea in expiration accompanied by cyanosis or pallor. The sequence of events may include bradycardia, loss of consciousness, abnormal postural tone and even asystole. A review of the literature revealed only two reports of postoperative apnea caused by "shortness of breath". this article describes the case of a child with a history of "shortness of breath" undiagnosed before the adenotonsillectomy, but that represented the cause of episodes of hypoxemia and bradycardia in the postoperative period. the "shortness of breath" crisis should be considered as a possible cause of perioperative hypoxia in children, especially when there is a history suggestive of this problem. As some events may be accompanied by bradycardia, loss of consciousness, abnormal postural tone and even asystole, observation in a hospital setting should be considered. Copyright © 2013 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

Postural stability of preoperative acoustic neuroma patients assessed by sway magnetometry: are they unsteady?

PubMed

Collins, Melanie M; Johnson, Ian J M; Clifford, Elaine; Birchall, John P; O'Donoghue, Gerald M

2003-04-01

The objective was to evaluate the preoperative postural stability of acoustic neuroma patients using sway magnetometry. Prospective two-center study. Fifty-one patients (mean age, 53 years) diagnosed with unilateral acoustic neuroma on magnetic resonance imaging at two tertiary referral centers were studied. Preoperatively, each patient had sway patterns (with eyes open and with eyes closed, and standing on foam) recorded for 120 seconds by sway magnetometry. Path length for 30 seconds was calculated. The Romberg coefficient (path length with eyes open divided by path length with eyes closed) was calculated. Forty-four percent of patients had abnormal path lengths with eyes open, and 49% with eyes closed. The Romberg coefficients were significantly lower than normal (P <.001; 95% CI, 0.19-0.87). Mean Romberg coefficient was 0.59 (normal value = 0.73), and all patients had a coefficient of less than 1. Half of preoperative acoustic neuroma patients are unsteady, exhibiting abnormal sway patterns based on path length measurements. The increase in sway path length demonstrable in normal subjects with eyes closed was significantly exaggerated in patients with acoustic neuroma.

["Loss of breath" as a cause of postoperative hypoxia and bradycardia in children submitted to tonsillectomy].

PubMed

Moro, Eduardo Toshiyuki; Goulart, Alexandre Palmeira

2015-01-01

The "shortness of breath" or "breathing interruption" crisis can be considered a cause of hypoxia in childhood. It is characterized by the presence of a triggering factor followed by weeping and apnea in expiration accompanied by cyanosis or pallor. The sequence of events may include bradycardia, loss of consciousness, abnormal postural toneand even asystole. A review of the literature revealed only two reports of postoperative apneacaused by "shortness of breath". This article describes the case of a child with a history of "shortness of breath" undiagnosed before the adenotonsillectomy, but that represented the cause of episodes of hypoxemia and bradycardia in the postoperative period. the "shortness of breath" crisis should be considered as a possible cause of perioperative hypoxia in children, especially when there is a history suggestive of this problem. As some events may be accompanied by bradycardia, loss of consciousness, abnormal postural tone and even asystole, observation in a hospital setting should be considered. Copyright © 2013 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

Real-time head movement system and embedded Linux implementation for the control of power wheelchairs.

PubMed

Nguyen, H T; King, L M; Knight, G

2004-01-01

Mobility has become very important for our quality of life. A loss of mobility due to an injury is usually accompanied by a loss of self-confidence. For many individuals, independent mobility is an important aspect of self-esteem. Head movement is a natural form of pointing and can be used to directly replace the joystick whilst still allowing for similar control. Through the use of embedded LINUX and artificial intelligence, a hands-free head movement wheelchair controller has been designed and implemented successfully. This system provides for severely disabled users an effective power wheelchair control method with improved posture, ease of use and attractiveness.

Spatial Reorientation of Sensorimotor Balance Control in Altered Gravity

NASA Technical Reports Server (NTRS)

Paloski, W. H.; Black, F. L.; Kaufman, G. D.; Reschke, M. F.; Wood, S. J.

2007-01-01

Sensorimotor coordination of body segments following space flight are more pronounced after landing when the head is actively tilted with respect to the trunk. This suggests that central vestibular processing shifts from a gravitational frame of reference to a head frame of reference in microgravity. A major effect of such changes is a significant postural instability documented by standard head-erect Sensory Organization Tests. Decrements in functional performance may still be underestimated when head and gravity reference frames remained aligned. The purpose of this study was to examine adaptive changes in spatial processing for balance control following space flight by incorporating static and dynamic tilts that dissociate head and gravity reference frames. A second aim of this study was to examine the feasibility of altering the re-adaptation process following space flight by providing discordant visual-vestibular-somatosensory stimuli using short-radius pitch centrifugation.

Acute responses of American kestrels to methyl parathion and fenvalerate

USGS Publications Warehouse

Rattner, B.A.; Franson, J.C.

1984-01-01

Physiological and toxicological effects of p.o, methyl parathion (0.375-3.0 mg/kg) or fenvalerate (1000-4000 mg/kg) were examined over a 10 h period in American kestrels (Falco sparverius) maintained in thermoneutral (22?.C) and cold (-5?.C) environments. Methyl parathion was highly toxic (LD50=3.08 mg/kg, 95% confidence limits=2.29-4.l4 mg/kg, producing overt intoxication (abnormal posture, ataxia, paresis), dose-dependent inhibition (26-67%) of brain acetylcholinesterase activity, hyperglycemia, and elevated plasma corticosterone concentration. Transient but pronounced hypothermia was associated with plasma cholinesterase inhibition in excess of 50% (2 h after intubation), although this response was highly variable (plasma ChE inhibition vs. A cloacal temperature, r=-0.60). Fenvalerate, at doses far exceeding those encountered in the environment, caused mild intoxication (irregular head movement) and elevated plasma alanine aminotransferase activity, but did not alter cloacal temperature, plasma activities of CK, U-HBDH, and LDK, or concentrations of corticosterone, glucose, triiodothyronine, and uric acid. Cold exposure intensified methyl parathion toxicity, but did not affect that of fenvalerate. It would thus appear that the organophosphorus insecticide methyl parathion poses far greater hazard than the pyrethroid fenvalerate to raptorial birds.

Efficacy and Safety of Pedunculopontine Nuclei (PPN) Deep Brain Stimulation in the Treatment of Gait Disorders: A Meta-Analysis of Clinical Studies.

PubMed

Golestanirad, Laleh; Elahi, Behzad; Graham, Simon J; Das, Sunit; Wald, Lawrence L

2016-01-01

Pedunculopontine nucleus (PPN) has complex reciprocal connections with basal ganglia, especially with internal globus pallidus and substantia nigra, and it has been postulated that PPN stimulation may improve gait instability and freezing of gait. In this meta-analysis, we will assess the evidence for PPN deep brain stimulation in treatment of gait and motor abnormalities especially focusing on Parkinson disease patients. PubMed and Scopus electronic databases were searched for related studies published before February 2014. Medline (1966-2014), Embase (1974-2010), CINAHL, Web of Science, Scopus bibliographic, and Google Scholar databases (1960-2014) were also searched for studies investigating effect of PPN deep brain stimulation in treatment of postural and postural instability and total of ten studies met the inclusion criteria for this analysis. Our findings showed a significant improvement in postural instability (p<0.001) and motor symptoms of Parkinson disease on and off medications (p<0.05), but failed to show improvement in freezing of gait. Despite significant improvement in postural instability observed in included studies, evidence from current literature is not sufficient to generalize these findings to the majority of patients.

Influence of vision and dental occlusion on body posture in pilots.

PubMed

Baldini, Alberto; Nota, Alessandro; Cravino, Gaia; Cioffi, Clementina; Rinaldi, Antonio; Cozza, Paola

2013-08-01

Air force pilots have great postural control, movement coordination, motor learning, and motor transformation. They undergo abnormal stresses during flight that affect their organs and systems, with consequences such as barodontalgia, bruxism, TMJ dysfunctions, and cervical pain. The aim of this study was to evaluate the influence of dental occlusion and vision on their body posture. In collaboration with the "A. Mosso" Legal Medical Institute (Aeronautica Militare), two groups, consisting of 20 air force and 20 civilian pilots, were selected for the study using a protocol approved by the Italian Air Force. An oral examination and a force platform test were performed in order to evaluate the subjects' postural system efficiency. A MANOVA (Multivariate analysis of variance) analysis was performed by using the Wilkes' criterion, in order to statistically evaluate the influence of each factor. Both the sway area and velocity parameters are very strongly influenced by vision: the sway area increases by approximately 32% and the sway velocity increases by approximately 50% when the pilot closes his eyes. Only the sway area parameter was significantly influenced by the mandibular position: the mandibular position with eyes open changed the sway area by about 51% and with eyes closed by about 40%. No statistically significant differences were found between air force and civilian pilots. The results of this analysis show that occlusion and visual function could influence posture in air force and civilian pilots.

The demands of professional opera singing on cranio-cervical posture

PubMed Central

Skinner, Margot

2009-01-01

Difficulty with singing is a rare but important complication following cervical spine surgery but there is little objective information regarding the cervical and head postural changes taking place during singing. The aim of this study was to identify postural changes in the cranio-cervical region associated with the demands of voice production in professional opera singing. The two Roentgen-cephalograms, one of which are taken whilst performing a specified singing task were taken from 18 professional opera students, 12 females (mean age 20.86 ± 3.07 years) and six males (18.66 ± 1.36 years). A paired t test compared mean cranio-cervical postural and pharyngeal/hyoid variables between the two registrations (P = 0.05). The association between the cranio-cervical postural variables and the pharyngeal/hyoid region in each registration position was examined using Spearman’s rank correlation coefficient. In singing, the position of the atlas with respect to the true vertical (P < 0.001), the axis (P < 0.001) and the C4 vertebra both with respect to the horizontal (P < 0.001), and the axis with respect to the cranium (P < 0.001), were all significantly different to those at rest. Of the cranio-cervical postural variables in the singing registration, the angles measuring positional change of the atlas and C4 relative to the true horizontal were shown be significantly related to an increased pharyngeal airway space at the C3 level (P < 0.01). An appreciation of the requirement for the cervical spine to undergo postural change during professional opera singing has relevance to the potential impact on voice quality in professional opera singers should they undergo cervical spine surgery. PMID:19165506

Mental rotation of body parts and sensory temporal discrimination in fixed dystonia.

PubMed

Katschnig, Petra; Edwards, Mark J; Schwingenschuh, Petra; Aguirregomozcorta, Maria; Kägi, Georg; Rothwell, John C; Bhatia, Kailash P

2010-06-15

Fixed dystonia is an uncommon but severely disabling condition typically affecting young women following a minor peripheral injury. There is no evidence of any structural lesions of the central nervous system nor any clear peripheral nerve or root damage. Electrophysiological techniques such as short intracortical inhibition, cortical silent period and a plasticity inducing protocol have revealed similarities but also differences compared to classical mobile dystonia. To further explore the pathophysiology of fixed dystonia we compared mental rotation of body parts and sensory temporal discrimination in 11 patients with fixed dystonia, 11 patients with classical mobile dystonia and 10 healthy controls. In the mental rotation task subjects were presented with realistic photos of left or right hands, feet and the head of a young women with a black patch covering the left or the right eye in six different orientations. Subjects had to verbally report the laterality of the presented stimuli. To assess sensory temporal discrimination subjects were asked to discriminate whether pairs of visual, tactile (electrical), or visuo-tactile stimuli were simultaneous or sequential (temporal discrimination threshold) and in the latter case which stimulus preceded the other (temporal order judgement). In accordance with previous studies patients with mobile dystonia were abnormal in mental rotation and temporal discrimination, whereas patients with fixed dystonia were only impaired in mental rotation. Possible explanations for this deficit may include the influence of the abnormal body posture itself, a shared predisposing pathophysiology for mobile and fixed dystonia, or a body image disturbance. These findings add information to the developing pathophysiological picture of fixed dystonia. (c) 2010 Movement Disorder Society.

Future of United States Cyber: Examining the Past to Posture the Future

DTIC Science & Technology

2013-12-13

the Army. This proved especially beneficial during the 1962 Cuban Missile Crisis, when the Soviet Union retracted from Cuba based highly on the...restaurants, retailers, etc. from declined tourism in major cities around the U.S.83 In March 2013, the head of U.S. Cyber Command, General Keith

Yoga and physical exercise - a review and comparison.

PubMed

Govindaraj, Ramajayam; Karmani, Sneha; Varambally, Shivarama; Gangadhar, B N

2016-06-01

Yoga is a multifaceted spiritual tool with enhanced health and well-being as one of its positive effects. The components of yoga which are very commonly applied for health benefits are asanas (physical postures), pranayama (regulated breathing) and meditation. In the context of asanas, yoga resembles more of a physical exercise, which may lead to the perception that yoga is another kind of physical exercise. This article aims at exploring the commonalities and differences between yoga and physical exercise in terms of concepts, possible mechanisms and effectiveness for health benefits. A narrative review is undertaken based on traditional and contemporary literature for yoga, along with scientific articles available on yoga and exercise including head-to-head comparative trials with healthy volunteers and patients with various disease conditions. Physical exercises and the physical components of yoga practices have several similarities, but also important differences. Evidence suggests that yoga interventions appear to be equal and/or superior to exercise in most outcome measures. Emphasis on breath regulation, mindfulness during practice, and importance given to maintenance of postures are some of the elements which differentiate yoga practices from physical exercises.

Pre-impact fall detection system using dynamic threshold and 3D bounding box

NASA Astrophysics Data System (ADS)

Otanasap, Nuth; Boonbrahm, Poonpong

2017-02-01

Fall prevention and detection system have to subjugate many challenges in order to develop an efficient those system. Some of the difficult problems are obtrusion, occlusion and overlay in vision based system. Other associated issues are privacy, cost, noise, computation complexity and definition of threshold values. Estimating human motion using vision based usually involves with partial overlay, caused either by direction of view point between objects or body parts and camera, and these issues have to be taken into consideration. This paper proposes the use of dynamic threshold based and bounding box posture analysis method with multiple Kinect cameras setting for human posture analysis and fall detection. The proposed work only uses two Kinect cameras for acquiring distributed values and differentiating activities between normal and falls. If the peak value of head velocity is greater than the dynamic threshold value, bounding box posture analysis will be used to confirm fall occurrence. Furthermore, information captured by multiple Kinect placed in right angle will address the skeleton overlay problem due to single Kinect. This work contributes on the fusion of multiple Kinect based skeletons, based on dynamic threshold and bounding box posture analysis which is the only research work reported so far.

[Vojta's method as the early neurodevelopmental diagnosis and therapy concept].

PubMed

Banaszek, Grazyna

2010-01-01

Vaclav Vojta (1917-2000) developed an early diagnostic method of the neurodevelopmental disorder of infants and came up with therapeutic concept consisting in releasing of global motor complexes by means of the stimulation of proper areas on patients body. In the diagnostics apart from very careful observation of the spontaneous movement of the infant and examination of the reflexes that are characteristic for the first weeks of human's life, Vojta applied the examination of the 7 postural reactions. Presence of the trouble in patterns and dynamics of the postural reactions Vojta called Central Nervous Coordination Disorder--CNCD and regarded as work diagnosis or alarm signal indicating necessity of application of the therapy, especially when asymmetry of the muscle tone and primitive reflexes beyond their physiological appearance period are observed or the number of the abnormal reactions exceeds 5. Global motor complexes as reflex locomotion--crawling and rotation--consist of all the partial motion patterns, which are gradually used by healthy infant in the process of postural and motor ontogenesis. Providing the central nervous system with proper external stimulation allows to, using neuronal plasticity, recreate an access to the human's postural development program and gradually replace pathological motor patterns by those more regular. Exercises repeated several times a day rebuilt support, erectile and vertical mechanisms, improve automatic postural control and phase lower limb movement. Affecting especially on autochtonic muscles of the spine exercises balance synergic cooperation of muscle groups in the trunk and those surrounding key body joints. This way they correct body's posture and peripheral motion and pathology of the outlasted primitive reflexes gradually withdraws.

Metacarpal head biomechanics: a comparative backscattered electron image analysis of trabecular bone mineral density in Pan troglodytes, Pongo pygmaeus, and Homo sapiens.

PubMed

Zeininger, Angel; Richmond, Brian G; Hartman, Gideon

2011-06-01

Great apes and humans use their hands in fundamentally different ways, but little is known about joint biomechanics and internal bone variation. This study examines the distribution of mineral density in the third metacarpal heads in three hominoid species that differ in their habitual joint postures and loading histories. We test the hypothesis that micro-architectural properties relating to bone mineral density reflect habitual joint use. The third metacarpal heads of Pan troglodytes, Pongo pygmaeus, and Homo sapiens were sectioned in a sagittal plane and imaged using backscattered electron microscopy (BSE-SEM). For each individual, 72 areas of subarticular cortical (subchondral) and trabecular bone were sampled from within 12 consecutive regions of the BSE-SEM images. In each area, gray levels (representing relative mineralization density) were quantified. Results show that chimpanzee, orangutan, and human metacarpal III heads have different gray level distributions. Weighted mean gray levels (WMGLs) in the chimpanzee showed a distinct pattern in which the 'knuckle-walking' regions (dorsal) and 'climbing' regions (palmar) are less mineralized, interpreted to reflect elevated remodeling rates, than the distal regions. Pongo pygmaeus exhibited the lowest WMGLs in the distal region, suggesting elevated remodeling rates in this region, which is loaded during hook grip hand postures associated with suspension and climbing. Differences among regions within metacarpal heads of the chimpanzee and orangutan specimens are significant (Kruskal-Wallis, p < 0.001). In humans, whose hands are used for manipulation as opposed to locomotion, mineralization density is much more uniform throughout the metacarpal head. WMGLs were significantly (p < 0.05) lower in subchondral compared to trabecular regions in all samples except humans. This micro-architectural approach offers a means of investigating joint loading patterns in primates and shows significant differences in metacarpal joint biomechanics among great apes and humans. Copyright © 2011 Elsevier Ltd. All rights reserved.

Primary postural instability: a cause of recurrent sudden falls in the elderly.

PubMed

Djaldetti, R; Lorberboym, M; Melamed, E

2006-12-01

Elderly patients with recurrent falls are frequently diagnosed with an extrapyramidal syndrome. This study aims to characterise a distinct group of patients with recurrent falls and postural instability as a hallmark of the clinical examination. The study took place in the Movement Disorders Unit, Rabin Medical Center, Petah Tiqva, Israel among 26 patients with recurrent falls who had no clinical evidence of a neurodegenerative disease. Medical records, neurological examination and brain imaging studies were assessed. Falls in these patients were sudden, unprovoked, with no vertigo or loss of consciousness. All had postural instability with minimal or no abnormality on the neurological examination. Brain imaging showed diffuse ischaemic changes in 65%. [(123)I]-FPCIT SPECT with the dopamine transporter ligand, performed in five patients, was normal in all. Recurrent falls might be caused by a neurological syndrome that primarily affects balance control. The importance of identifying this disorder is its distinction from other parkinsonian syndromes causing falls.

A procedure to detect abnormal sensorimotor control in adolescents with idiopathic scoliosis.

PubMed

Pialasse, Jean-Philippe; Mercier, Pierre; Descarreaux, Martin; Simoneau, Martin

2017-09-01

This work identifies, among adolescents with idiopathic scoliosis, those demonstrating impaired sensorimotor control through a classification procedure comparing the amplitude of their vestibular-evoked postural responses. The sensorimotor control of healthy adolescents (n=17) and adolescents with idiopathic scoliosis (n=52) with either mild (Cobb angle≥15° and ≤30°) or severe (Cobb angle >30°) spine deformation was assessed through galvanic vestibular stimulation. A classification procedure sorted out adolescents with idiopathic scoliosis whether the amplitude of their vestibular-evoked postural response was dissimilar or similar to controls. Compared to controls, galvanic vestibular stimulation evoked larger postural response in adolescents with idiopathic scoliosis. Nonetheless, the classification procedure revealed that only 42.5% of all patients showed impaired sensorimotor control. Consequently, identifying patients with sensorimotor control impairment would allow to apply personalized treatments, help clinicians to establish prognosis and hopefully improve the condition of patients with adolescent idiopathic scoliosis. Copyright © 2017 Elsevier B.V. All rights reserved.

Postural Control Disturbances Produced By Exposure to HMD and Dome Vr Systems

NASA Technical Reports Server (NTRS)

Harm, D. L.; Taylor, L. C.

2005-01-01

Two critical and unresolved human factors issues in VR systems are: 1) potential "cybersickness", a form of motion sickness which is experienced in virtual worlds, and 2) maladaptive sensorimotor performance following exposure to VR systems. Interestingly, these aftereffects are often quite similar to adaptive sensorimotor responses observed in astronauts during and/or following space flight. Most astronauts and cosmonauts experience perceptual and sensorimotor disturbances during and following space flight. All astronauts exhibit decrements in postural control following space flight. It has been suggested that training in virtual reality (VR) may be an effective countermeasure for minimizing perceptual and/or sensorimotor disturbances. People adapt to consistent, sustained alterations of sensory input such as those produced by microgravity, and experimentally-produced stimulus rearrangements (e.g., reversing prisms, magnifying lenses, flight simulators, and VR systems). Adaptation is revealed by aftereffects including perceptual disturbances and sensorimotor control disturbances. The purpose of the current study was to compare disturbances in postural control produced by dome and head-mounted virtual environment displays. Individuals recovered from motion sickness and the detrimental effects of exposure to virtual reality on postural control within one hour. Sickness severity and initial decrements in postural equilibrium decreases over days, which suggests that subjects become dual-adapted over time. These findings provide some direction for developing training schedules for VR users that facilitate adaptation, and address safety concerns about aftereffects.

Effects of neck exercise on high-school students' neck-shoulder posture.

PubMed

Lee, Myoung-Hyo; Park, Su-Jin; Kim, Jin-Sang

2013-05-01

[Purpose] This study examined the effects of deep flexor muscle-strengthening exercise on the neck-shoulder posture, and the strength and endurance of the deep flexor muscles of high-school students. [Subjects] The subjects were 30 seventeen-year-old female high-school students who complained about bad posture and chronic neck-shoulder pain. They were randomly divided into an experimental group of 15 subjects, who performed a deep flexor muscle-strengthening exercise and a control group of 15 subjects, who performed a basic stretching exercise. [Methods] The experimental group of 15 subjects performed a deep flexor muscle-strengthening exercise consisting of low-load training of the cranio-cervical flexor muscle, and the control group of 15 subjects performed a basic stretching exercise consisting of seven motions. [Results] The experimental group showed statistically significant changes in head tilt angle, neck flexion angle, forward shoulder angle, and the result of the cranio-cervical flexion test after the training. In contrast, the control group showed no statistically significant changes in these measures following the training. When the results of the groups were compared, statistically significant differences were found for all items between the experimental group and the control group. [Conclusion] Strengthening cranio-cervical flexor muscles is important for the adjustment of neck posture, and maintaining their stability is required to improve neck-shoulder posture.

Ergonomics in the operating room: protecting the surgeon.

PubMed

Rosenblatt, Peter L; McKinney, Jessica; Adams, Sonia R

2013-01-01

To review elements of an ergonomic operating room environment and describe common ergonomic errors in surgeon posture during laparoscopic and robotic surgery. Descriptive video based on clinical experience and a review of the literature (Canadian Task Force classification III). Community teaching hospital affiliated with a major teaching hospital. Gynecologic surgeons. Demonstration of surgical ergonomic principles and common errors in surgical ergonomics by a physical therapist and surgeon. The physical nature of surgery necessitates awareness of ergonomic principles. The literature has identified ergonomic awareness to be grossly lacking among practicing surgeons, and video has not been documented as a teaching tool for this population. Taking this into account, we created a video that demonstrates proper positioning of monitors and equipment, and incorrect and correct ergonomic positions during surgery. Also presented are 3 common ergonomic errors in surgeon posture: forward head position, improper shoulder elevation, and pelvic girdle asymmetry. Postural reset and motion strategies are demonstrated to help the surgeon learn techniques to counterbalance the sustained and awkward positions common during surgery that lead to muscle fatigue, pain, and degenerative changes. Correct ergonomics is a learned and practiced behavior. We believe that video is a useful way to facilitate improvement in ergonomic behaviors. We suggest that consideration of operating room setup, proper posture, and practice of postural resets are necessary components for a longer, healthier, and pain-free surgical career. Copyright © 2013 AAGL. Published by Elsevier Inc. All rights reserved.

Regulation of hematopoiesis in rats exposed to antiorthostatic hypokinetic/hypodynamia. II - Mechanisms of the 'anemia'

NASA Technical Reports Server (NTRS)

Dunn, C. D. R.; Johnson, P. C.; Lange, R. D.

1986-01-01

The cause of the red cell mass (RCM) deficit, which occurs in rats during suspenion, is investigated. The experimental conditions and procedures, in which male Sprague-Dawley rats are subjected to antiorthostatic hyypokinetic/hypodynamia and changes in RCM are monitored, are described. The influences of stress, reduced food and water consumption, and antiorhostatic posture on RCM are analyzed. Changes in body weight, RCM, radioiron incorporation, red blood cells (RBC), and reticulocytes, for the rats after head-down suspension are graphically presented; only the changes in RBC are related to the antiorthostatic posture. The data reveal that anemia is primarily caused by reduced food and water consumption and secondly by restricted movements.

Simulation of Cardiovascular Response to the Head-Up/Head-Down Tilt at Different Angles

NASA Astrophysics Data System (ADS)

Liu, Yang; Lu, Hong-Bing; Jiao, Chun; Zhang, Li-Fan

2008-06-01

The disappearance of hydrostatic pressure is the original factor that causes the changes of cardiovascular system under microgravity. The hydrostatical changes can be simulated by postural changes. Especially the head-down position can be used to simulate the effects of microgravity. The goal of this investigation was to develop a mathematical model for simulation of the human cardiovascular responses to acute and prolonged exposure under microgravity environment. We were particularly interested in the redistribution of transmural pressures, flows, blood volume, and the consequent alterations in local hemodynamics in different cardiovascular compartments during acute exposure and chronic adjustments. As a preliminary study, we first developed a multi-element, distributed hemodynamic model of human cardiovascular system, and verified the model to simulate cardiovascular changes during head up/down tilt at various angles.

A necropsy and histomorphometric study of abnormalities in the course of the vertebral artery associated with ossified stylohyoid ligaments.

PubMed Central

Johnson, C P; Scraggs, M; How, T; Burns, J

1995-01-01

AIMS--To establish whether abnormalities in the course of the vertebral artery occur and whether they are relevant to arterial injury associated with head and neck movements. METHODS--Twenty vertebral arteries were carefully dissected at necropsy and abnormalities in course were noted, along with any other bony or cartilaginous cervical anomalies. The effect of head and neck movement on these vessels was studied before a detailed histomorphometric examination was undertaken on sections of the excised arteries. RESULTS--Five vessels had an abnormal course. One vessel entered the transverse foramina of the fifth cervical vertebra rather than the sixth, but was otherwise normal. In two subjects both vertebral arteries were abnormal in the upper cervical portion with, in each case, a straight left vertebral artery and a right vertebral artery with a deficient loop, closely applied to the atlanto-axial joint. Both of these subjects also had completely ossified stylohyoid ligaments and the arteries visibly stretched with modest head and neck movements. Histology revealed variable degrees of smooth muscle disarray in the tunica media of two of the arteries with loop deficiencies. The circumference of one of the straight arteries was smaller than expected but in all other measured histomorphometric parameters these vessels appeared normal. CONCLUSIONS--Vertebral artery loops are deficient in a number of subjects. This finding is important given the recently described biomechanical susceptibility of the vertebral artery to longitudinal extension and may explain the smooth muscle changes, in that this may represent attempts at arterial wall remodelling. Subjects with such loop deficiencies may be more susceptible to a variety of head and neck insults and such abnormalities should be sought at necropsy in subjects who die as a result of fatal vertebral artery injury. Images PMID:7560170

Patients who reattend after head injury: a high risk group.

PubMed Central

Voss, M.; Knottenbelt, J. D.; Peden, M. M.

1995-01-01

OBJECTIVE--To assess risk factors for important neurosurgical effects in patients who reattend after head injury. DESIGN--Retrospective study. SUBJECTS--606 patients who reattended a trauma unit after minor head injury. MAIN OUTCOME MEASURES--Intracranial abnormality detected on computed tomography or the need for neurosurgical intervention. RESULTS--Five patients died: two from unrelated causes and three from raised intracranial pressure. On multiple regression analysis the only significant predictor for both abnormality on computed tomography (14.4% of reattenders) and the need for operation (5% of reattenders) was vault fracture seen on the skull radiograph (P < 10(-6)); predictors for abnormal computed tomogram were a Glasgow coma scale score < 15 at either first or second attendance (P < 0.0001) and convulsion at second attendance (P < 0.05); predictive for operation only was penetrating injury of the skull (P < 10(-6)). On contingency table analysis these associations were confirmed. In addition significant associations with both abnormality on computed tomography and operation were focal neurological abnormality, weakness, or speech disturbance. Amnesia or loss of consciousness at the time of initial injury, personality change, and seizures were significantly associated only with abnormality on computed tomography. Headache, dizziness, nausea, and vomiting were common in reattenders but were found to have no independent significance. CONCLUSIONS--All patients who reattend after head injury should undergo computed tomography as at least 14% of scans can be expected to yield positive results. Where this facility is not available patients with predictors for operation should be urgently referred for neurosurgical opinion. Other patients can be readmitted and need referral only if symptoms persist despite symptomatic treatment or there is neurological deterioration while under observation. These patients are a high risk group and should be treated seriously. PMID:8520273

Role of Visual Feedback Treatment for Defective /s/ Sounds in Patients with Cleft Palate.

ERIC Educational Resources Information Center

Michi, Ken-ichi; And Others

1993-01-01

Six patients with cleft palate were provided treatment using either visual feedback for tongue placement and frication or no visual feedback. Results indicated the feedback was especially useful in the treatment of defective /s/ sounds in the patients who exhibited abnormal posterior tongue posturing during dental or alveolar sounds. (Author/DB)

Understanding the pusher behavior of some stroke patients with spatial deficits: a pilot study.

PubMed

Pérennou, Dominic Alain; Amblard, Bernard; Laassel, El Mostafa; Benaim, Charles; Hérisson, Christian; Pélissier, Jacques

2002-04-01

To investigate whether pusher behavior (ie, a tendency among stroke patients with spatial deficits to actively push away from the nonparalyzed side and to resist any attempt to hold a more upright posture) affects only the trunk, for which gravitational feedback is given by somesthetic information, or the head as well, whose gravitational information is mainly given by the vestibular system (without vision). Description and measurement of clinical features. Rehabilitation center research laboratory. Eight healthy subjects age matched to 14 patients with left hemiplegia resulting from right-hemisphere stroke (3 pushers showing a severe spatial neglect, 11 without pusher behavior). All participants were asked to actively maintain an erect posture while sitting for 8 seconds on a rocking, laterally unstable platform. The task was performed with (in light) and without (in darkness) vision. The number of trials needed to succeed in the task was monitored. In successful trials, head, shoulders, thoracolumbar spine, and pelvis orientation in roll were measured by means of an automated, optical television image processor. Compared with other patients and healthy subjects, the 3 pushers missed many more trials and displayed a contralesional tilt of the pelvis but kept a correct head orientation. This tilt was especially pronounced without vision. Spatial neglect was a key factor, explaining 56% of patients' misorientation behavior with vision and 61% without vision. This pilot kinematic analysis shows that pusher behavior does not result from disrupted processing of vestibular information (eg, caused by a lesion involving the vestibular cortex); rather, it results from a high-order disruption in the processing of somesthetic information originating in the left hemibody, which could be graviceptive neglect (extinction). This disruption leads pushers to actively adjust their body posture to a subjective vertical biased to the side opposite the cerebral lesion. Copyright 2002 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Comparison of conversion coefficients for equivalent dose in terms of air kerma for photons using a male adult voxel simulator in sitting and standing posture with geometry of irradiation antero-posterior

NASA Astrophysics Data System (ADS)

Galeano, D. C.; Cavalcante, F. R.; Carvalho, A. B.; Hunt, J.

2014-02-01

The dose conversion coefficient (DCC) is important to quantify and assess effective doses associated with medical, professional and public exposures. The calculation of DCCs using anthropomorphic simulators and radiation transport codes is justified since in-vivo measurement of effective dose is extremely difficult and not practical for occupational dosimetry. DCCs have been published by the ICRP using simulators in a standing posture, which is not always applicable to all exposure scenarios, providing an inaccurate dose estimation. The aim of this work was to calculate DCCs for equivalent dose in terms of air kerma (H/Kair) using the Visual Monte Carlo (VMC) code and the VOXTISS8 adult male voxel simulator in sitting and standing postures. In both postures, the simulator was irradiated by a plane source of monoenergetic photons in antero-posterior (AP) geometry. The photon energy ranged from 15 keV to 2 MeV. The DCCs for both postures were compared and the DCCs for the standing simulator were higher. For certain organs, the difference of DCCs were more significant, as in gonads (48% higher), bladder (16% higher) and colon (11% higher). As these organs are positioned in the abdominal region, the posture of the anthropomorphic simulator modifies the form in which the radiation is transported and how the energy is deposited. It was also noted that the average percentage difference of conversion coefficients was 33% for the bone marrow, 11% for the skin, 13% for the bone surface and 31% for the muscle. For other organs, the percentage difference of the DCCs for both postures was not relevant (less than 5%) due to no anatomical changes in the organs of the head, chest and upper abdomen. We can conclude that is important to obtain DCCs using different postures from those present in the scientific literature.

Distinct neurohumoral biomarker profiles in children with hemodynamically defined orthostatic intolerance may predict treatment options

PubMed Central

Wagoner, Ashley L.; Shaltout, Hossam A.; Fortunato, John E.

2015-01-01

Studies of adults with orthostatic intolerance (OI) have revealed altered neurohumoral responses to orthostasis, which provide mechanistic insights into the dysregulation of blood pressure control. Similar studies in children with OI providing a thorough neurohumoral profile are lacking. The objective of the present study was to determine the cardiovascular and neurohumoral profile in adolescent subjects presenting with OI. Subjects at 10–18 yr of age were prospectively recruited if they exhibited two or more traditional OI symptoms and were referred for head-up tilt (HUT) testing. Circulating catecholamines, vasopressin, aldosterone, renin, and angiotensins were measured in the supine position and after 15 min of 70° tilt. Heart rate and blood pressure were continuously measured. Of the 48 patients, 30 patients had an abnormal tilt. Subjects with an abnormal tilt had lower systolic, diastolic, and mean arterial blood pressures during tilt, significantly higher levels of vasopressin during HUT, and relatively higher catecholamines and ANG II during HUT than subjects with a normal tilt. Distinct neurohumoral profiles were observed when OI subjects were placed into the following groups defined by the hemodynamic response: postural orthostatic tachycardia syndrome (POTS), orthostatic hypotension (OH), syncope, and POTS/syncope. Key characteristics included higher HUT-induced norepinephrine in POTS subjects, higher vasopressin in OH and syncope subjects, and higher supine and HUT aldosterone in OH subjects. In conclusion, children with OI and an abnormal response to tilt exhibit distinct neurohumoral profiles associated with the type of the hemodynamic response during orthostatic challenge. Elevated arginine vasopressin levels in syncope and OH groups are likely an exaggerated response to decreased blood flow not compensated by higher norepinephrine levels, as observed in POTS subjects. These different compensatory mechanisms support the role of measuring neurohumoral profiles toward the goal of selecting more focused and mechanistic-based treatment options for pediatric patients with OI. PMID:26608337

Reducing patient posture variability using the predicted couch position

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kruijf, Wilhelmus J.M. de, E-mail: kruijf.de.w@bvi.nl; Martens, Rob J.W.

2015-10-01

A method is presented in which the couch position is predicted before the treatment instead of obtaining a reference position at the first treatment fraction. This prevents systematic differences in patient posture between preparation and treatment. In literature, only limited data are available on couch positioning. We position our patients at the planned couch position, allowing a small difference between skin marks and lasers, followed by online imaging. For a 3-month period, our standard deviations (mm) in couch position in the vertical, longitudinal, and lateral directions were head and neck—1.6, 2.8, and 2.5; thorax—2.9, 5.5, and 4.5; breast—3.0, 4.1, andmore » 4.0; and pelvis—3.5, 4.0, and 4.7, respectively. We have improved the reproducibility of patient posture in our institute by using the predicted couch position. Our data may serve as a reference for other institutes because the couch position variation is less than that published in literature.« less

The influence of an immersive virtual environment on the segmental organization of postural stabilizing responses.

PubMed

Keshner, E A; Kenyon, R V

2000-01-01

We examined the effect of a 3-dimensional stereoscopic scene on segmental stabilization. Eight subjects participated in static sway and locomotion experiments with a visual scene that moved sinusoidally or at constant velocity about the pitch or roll axes. Segmental displacements, Fast Fourier Transforms, and Root Mean Square values were calculated. In both pitch and roll, subjects exhibited greater magnitudes of motion in head and trunk than ankle. Smaller amplitudes and frequent phase reversals suggested control of the ankle by segmental proprioceptive inputs and ground reaction forces rather than by the visual-vestibular signals. Postural controllers may set limits of motion at each body segment rather than be governed solely by a perception of the visual vertical. Two locomotor strategies were also exhibited, implying that some subjects could override the effect of the roll axis optic flow field. Our results demonstrate task dependent differences that argue against using static postural responses to moving visual fields when assessing more dynamic tasks.

Effects of Document Holder on Postural Neck Muscles Activity among Computer Users: A Preliminary Study.

PubMed

Ambusam, Subramaniam; Omar, Baharudin; Joseph, Leonard; Deepashini, Harithasan

2015-01-01

Computer users are exposed to work related neck disorders due to repetitive movement and static posture for prolonged period. Viewing document and typing simultaneously are one of the contributing factors for neck disorders. This preliminary study was conducted to evaluate the effects of the document holder on the postural neck muscles activity among computer users. Nine healthy participants with pre-defined inclusion and exclusion criteria were recruited for the study. Neck muscles activity were analyzed using the surface electromyography (EMG) in five different document location such as flat right, flat left, flat center, stand right and stand left during a 5 min typing task. The mean and standard deviation results showed a least amount of muscles activity using a document holder compared to without document holder. Nevertheless, the statistical analysis showed no significant differences between the using of a document holder. The effects of document holder on head excursion and neck muscle activity is recommended in clinical neck pain population.

An abattoir survey of equine dental abnormalities in Queensland, Australia.

PubMed

Chinkangsadarn, T; Wilson, G J; Greer, R M; Pollitt, C C; Bird, P S

2015-06-01

A cadaver study to estimate the prevalence of dental disorders in horses presented at an abattoir in Queensland, Australia. Cadaver heads at a Queensland abattoir were examined for the presence of dental abnormalities and categorised into age groups. The prevalence of abnormalities was analysed by binomial observation of observed proportion, Pearson's Chi-square test or Fisher's exact correlation test. Strength of association was evaluated using Cramer's V test. Heads from horses (n=400) estimated to be between 1 and 30 years of age were placed into four age groups. The most common abnormalities were sharp enamel points (55.3%) and hooks (43%). The highest frequency of dental diseases and abnormalities were in horses 11-15 years old (97.5%). Common abnormalities were found in all groups and the prevalence increased with age. This study suggests that all horses should have regular complete dental examinations to detect and treat dental disorders in order to limit more severe dental pathologies later in life. © 2015 Australian Veterinary Association.

Numerical Investigation on Head and Brain Injuries Caused by Windshield Impact on Riders Using Electric Self-Balancing Scooters

PubMed Central

Zheng, Yanting; Shen, Ming; Yang, Xianfeng

2018-01-01

To investigate head-brain injuries caused by windshield impact on riders using electric self-balancing scooters (ESS). Numerical vehicle ESS crash scenarios are constructed by combining the finite element (FE) vehicle model and multibody scooter/rider models. Impact kinematic postures of the head-windshield contact under various impact conditions are captured. Then, the processes during head-windshield contact are reconstructed using validated FE head/laminated windshield models to assess the severity of brain injury caused by the head-windshield contact. Governing factors, such as vehicle speed, ESS speed, and the initial orientation of ESS rider, have nontrivial influences over the severity of a rider's brain injuries. Results also show positive correlations between vehicle speed and head-windshield impact speeds (linear and angular). Meanwhile, the time of head-windshield contact happens earlier when the vehicle speed is faster. According to the intensive study, windshield-head contact speed (linear and angular), impact location on the windshield, and head collision area are found to be direct factors on ESS riders' brain injuries during an impact. The von Mises stress and shear stress rise when relative contact speed of head-windshield increases. Brain injury indices vary widely when the head impacting the windshield from center to the edge or impacting with different areas. PMID:29770161

Cervical dystonia: effectiveness of a standardized physical therapy program; study design and protocol of a single blind randomized controlled trial

PubMed Central

2013-01-01

Background Cervical dystonia is characterized by involuntary muscle contractions of the neck and abnormal head positions that affect daily life activities and social life of patients. Patients are usually treated with botulinum toxin injections into affected neck muscles to relief pain and improve control of head postures. In addition, many patients are referred for physical therapy to improve their ability to perform activities of daily living. A recent review on allied health interventions in cervical dystonia showed a lack of randomized controlled intervention studies regarding the effectiveness of physical therapy interventions. Methods/design The (cost-) effectiveness of a standardized physical therapy program compared to regular physical therapy, both as add-on treatment to botulinum toxin injections will be determined in a multi-centre, single blinded randomized controlled trial with 100 cervical dystonia patients. Primary outcomes are disability in daily functioning assessed with the disability subscale of the Toronto Western Spasmodic Torticollis Rating Scale. Secondary outcomes are pain, severity of dystonia, active range of motion of the head, quality of life, anxiety and depression. Data will be collected at baseline, after six months and one year by an independent blind assessor just prior to botulinum toxin injections. For the cost effectiveness, an additional economic evaluation will be performed with the costs per quality adjusted life-year as primary outcome parameter. Discussion Our study will provide new evidence regarding the (cost-) effectiveness of a standardized, tailored physical therapy program for patients with cervical dystonia. It is widely felt that allied health interventions, including physical therapy, may offer a valuable supplement to the current therapeutic options. A positive outcome will lead to a greater use of the standardized physical therapy program. For the Dutch situation a positive outcome implies that the standardized physical therapy program forms the basis for a national treatment guideline for cervical dystonia. Trial registration Number Dutch Trial registration (Nederlands Trial Register): NTR3437 PMID:23855591

Cervical dystonia: effectiveness of a standardized physical therapy program; study design and protocol of a single blind randomized controlled trial.

PubMed

van den Dool, Joost; Visser, Bart; Koelman, J Hans T M; Engelbert, Raoul H H; Tijssen, Marina A J

2013-07-15

Cervical dystonia is characterized by involuntary muscle contractions of the neck and abnormal head positions that affect daily life activities and social life of patients. Patients are usually treated with botulinum toxin injections into affected neck muscles to relief pain and improve control of head postures. In addition, many patients are referred for physical therapy to improve their ability to perform activities of daily living. A recent review on allied health interventions in cervical dystonia showed a lack of randomized controlled intervention studies regarding the effectiveness of physical therapy interventions. The (cost-) effectiveness of a standardized physical therapy program compared to regular physical therapy, both as add-on treatment to botulinum toxin injections will be determined in a multi-centre, single blinded randomized controlled trial with 100 cervical dystonia patients. Primary outcomes are disability in daily functioning assessed with the disability subscale of the Toronto Western Spasmodic Torticollis Rating Scale. Secondary outcomes are pain, severity of dystonia, active range of motion of the head, quality of life, anxiety and depression. Data will be collected at baseline, after six months and one year by an independent blind assessor just prior to botulinum toxin injections. For the cost effectiveness, an additional economic evaluation will be performed with the costs per quality adjusted life-year as primary outcome parameter. Our study will provide new evidence regarding the (cost-) effectiveness of a standardized, tailored physical therapy program for patients with cervical dystonia. It is widely felt that allied health interventions, including physical therapy, may offer a valuable supplement to the current therapeutic options. A positive outcome will lead to a greater use of the standardized physical therapy program. For the Dutch situation a positive outcome implies that the standardized physical therapy program forms the basis for a national treatment guideline for cervical dystonia. Number Dutch Trial registration (Nederlands Trial Register): NTR3437.