Postural Support Research Articles

Modeling of processes for vertical posture support

Study the mechanisms for regulation of human posture is one of the urgent tasks of physiology of movement. This is due to significance of the results of research for development of methods for diagnosis and treatment of various disorders of the central nervous system (CNS) and the musculoskeletal system (MSS) as well as to theoreti cal elaborations concerning the general principles of organization of control of person’s movement. Objective: To conceptually deter mine the role of statogram as a result of interaction of the CNS and the execution system (ES) in the evaluation of the MSS function. Results: Based on the analysis of existing physiological models for maintaining of equilibrium there was developed a conceptual model of interaction between the CNS and the MSS for the person in maintaining upright posture. The system approach to the dif ferential assessment of the MSS on the basis of statography was proposed. The research process can be divided into three stages: I — definition of anthropometric parameters of the patient (weight, height, length of segments, bearing surface of feet); II — registra tion of movement of the common center of mass in the patient with natural standing, and the correlation of these parameters with the anthropometric data; III — study with using disturbances that meet location of the lesion, its nature and extent. The conclusion about the state of the MSS is formed on the basis of a comparative analysis of the results obtained in the second and third stages of the study. Conclusion: There were developed a conceptual model of the process of maintaining upright human posture as a system of automated management and justified the general direction of statographic studies when assessing the MSS function. Applying of methods of disturbances at statographic studies that allow to activate the affected elements of the MSS or block compensatory mechanisms was substantiated.

Measure it: proper wheelchair fit is key to ensuring function while protecting skin integrity.

The objectives of this article are to help the clinician to better recognize the basic biomechanics of posture, describe the appropriate means to configure a wheelchair to permit proper postural support, and to identify common problems arising from improper wheelchair fit.

Impaired Limb Reaction to Displacement of Center of Gravity in Rats with Unilateral Striatal Ischemic Injury

Clinical stroke often results in impaired balance and increased vulnerability to severe injuries due to falling. To evaluate potential preclinical treatments that might target these deficits, it will be important to include tests capable of assessing these impairments chronically in animal models. Previously, we developed a postural instability test (PIT) that revealed chronic, unilateral impairments in postural stability in rat models of hemi-Parkinson's disease (PD) and of unilateral cervical spinal cord injury. Here, we investigated whether this test was also capable of revealing long-term stroke-induced impairments in postural support in rats. Additionally, we examined the ability of more common tests of sensorimotor function to detect chronic impairments. We found that the PIT detected chronic deficits in postural stability/balance enduring for up to 6 weeks post-stroke, outlasting impairments detected in other tests of forelimb sensorimotor function, including asymmetries in upright postural support (cylinder test) and vibrissae-evoked forelimb placing.

Gait training of poststroke patients assisted by the Walkaround (body postural support)

Improvement in gait abilities is one of the important goals of stroke rehabilitation. The Walkaround is a new postural assistance device for gait training, which allows an early start for gait training. This device provides body postural support (BPS) and trunk orientation by means of a lumbar belt that is connected to a powered rolling walker. We conducted a randomized, single-blinded, 4-week clinical trial of 22 subacute stroke patients with a follow-up period of 6 months. Patients were divided into two identically sized groups: the treatment group (BPS), which was assisted by the Walkaround, and the control (CON) group, which was assisted by conventional means (cane, therapist) during gait training. The objective of the study was to assess whether the Walkaround is more effective than conventional assistance during gait training. The outcome measures were as follows: Barthel index, Fugl-Meyer score for the lower extremities, Berg balance test, and gait speed. Changes in the outcome measures were significant for the Berg balance score after 6 months in both groups and in gait speed among the BPS group at the end of therapy and after 6 months (P<0.05) compared with the same outcome measures at the beginning of the trial. Significant differences were found in gait speed and Berg balance test scores after 4 weeks and in gait speed after 6 months (P<0.05) between the BPS and the CON groups. The results suggest that added postural support by the Walkaround led to limited yet significant changes in gait speed and balance control.

Leucodistrofia Metacromática: Relato de Caso de Dois Irmãos Cosanguíneos

The Metachromatic Leukodystrophy (MLD) is an autosomal reces­sive lipidosis caused by the deficiency of the lysosomal enzyme ar­ylsulfatase A (ARSA), the clinical course of MLD evolves primarily with neurological dysfunction. Objective. describe the characteristics and clinical evolution of two brothers who have a diagnosis of MLD infant. Method. a case report of two brothers, one child was female with eight years of age and one male with six years of age. The medical history was collected through analysis of medical records, interviews, physical examination, physical therapy evaluation, assessment of muscle tone through Modified Scale Ashoworth, assessment of gross motor function through Classification System Gross Motor Function in MLD (GMFCS-MLD) old photos and current photos. Results. the clinical outcome in both cases began with gradual loss of postural support, increasing muscular hypertonia, muscle shortening and mus­culoskeletal deformities, loss of functionality and total dependence to perform activities of daily living. Conclusion. the clinical condition of the two brothers is similar and consistent with descriptions in the literature, however, the younger brother has shown clinical deteriora­tion fast.

Muscle synergies with Walkaround® postural support vs. “cane/therapist” assistance

The main clinical measures of walking recovery in stroke patients were compared for training assisted by Walkaround® postural support (WPS) and conventional (CON) support by a cane/therapist. We attributed the differences between the trainings to modified muscular synergies that occurred during assistance by WPS. We studied the muscle activities of the primary knee and ankle joint movers in the paretic and non-paretic legs of sub-acute stroke patients during assisted walking with WPS and CON. Recorded signals were compared to normative data that were recorded during speed-matched gait trials in healthy subjects. The specific measures were the relative contribution of individual muscles, levels of cocontraction, and the timing of the maximum electromyography (EMG) activity during the walking sessions. We found that, for most patients, the individual contribution of muscles were more similar to the healthy with the WPS assistance. In parallel, the cocontraction of the rectus femoris muscles in both legs was lower (by up to 39 %) during walking assisted by WPS than by cane/therapist gait support); the results from this case series (10 patients) showed that WPS might be the superior training scheme. These findings indicated that assistance by WPS changed the motor control output relative to CON assistance in most patients.

Children’s Catching Performance When the Demands on the Postural System Is Altered

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.

Typical and atypical development of reaching and postural control in infancy

Successful reaching requires postural control, either by active regulation or by postural support. The present paper reviews literature on typical and atypical development of reaching and postural control during infancy. Typically, reaching movements end in grasping around 4 months of age. Initially, reaches are characterized by large variation, including many trajectory corrections. During the first year, the movements get increasingly straight and smooth. Reaching in low-risk preterm infants is initially characterized by advanced development, but minor impairments may emerge in the second half of infancy. In high-risk preterm infants, development of reaching is characterized by delay and non-optimal reaching performance. Typical development of postural adjustments is characterized by variation and an increasing ability to adapt the variable repertoire to the specifics of the situation. The latter is facilitated by an increasing role of anticipatory mechanisms in the second half of infancy. Atypically developing infants may have a reduced repertoire and usually have difficulties in adapting postural adjustments. In infancy, most reaching movements are performed during sitting. The postural challenge of sitting may interfere in particular with the development of reaching in atypically developing infants. The practical implications of this suggestion are discussed.

The effect of Parkinson’s disease and levodopa on adaptation of anticipatory postural adjustments

Postural support alters anticipatory postural adjustments (APAs). Efficient adaptation to changes in postural support in reactive and centrally initiated postural synergies is impaired in Parkinson’s disease (PD). This study examined whether APAs are affected differently by familiar and novel supports in people with PD, ON and OFF levodopa. The effect of PD and levodopa on the ability to immediately adapt APAs to changes in support and refine with practice was also investigated. Fourteen people with PD and 14 healthy control participants performed 20 single rapid leg lift tasks in four support conditions: unsupported, bilateral handgrip (familiar), bite plate (novel) and a combined handgrip+bite plate condition. APAs, identified from force plate data, were characterized by an increase in the vertical ground reaction force under the lifted leg as a result of a shift of weight toward the stance limb. Results showed the ability to incorporate familiar and novel external supports into the postural strategy was preserved in PD. Controls and PD patients in the OFF state further refined the postural strategy with practice as evidenced by changes in amplitude of vertical ground reaction forces and forces applied to support apparatus within conditions between the initial and final trials. In the ON state, people with PD failed to refine the use of postural supports in any condition. The results suggest that immediate postural adaptation is intact in people with PD and unaffected by levodopa administration but the ability to refine postural adaptations with task experience is compromised by dopamine therapy.

Sit happens: Does sitting development perturb reaching development, or vice versa?

The development of reaching and of sitting during the first year of life is typically studied as separate yet related behaviors. Interestingly, very soon after learning to reach, 4–7-month-old infants start coordinating their arms with their trunk and legs for sitting. In this longitudinal study, we focused, for the first time, on how infants learn to use their arms for the dual tasks of reaching for objects while providing arm support as they learn to sit. We hypothesized that the use of arms for support during sitting development would be a temporary perturbation to reaching and result in a nonlinear progression of reaching skill.Eleven infants were studied monthly from the time they began to prop sit to the time of sitting independence (5–8 months of age). Behavioral coding, kinematics, and electromyography (EMG) characterized reaching and posture while infants sat as independently as possible. Results revealed significant changes across time in trunk movement and hand use as infants transitioned through three stages of sitting: with arm support, sitting briefly without arm support, and sitting independently. Infants used their hands more for contacting objects and less for posture support linearly across time. In contrast, changes in posture control as indicated by pelvis and trunk movement demonstrated a U-shaped curve with more movement of these two body segments during the middle stage of sitting than in the first or last stage. During the middle stage of sitting infants reached persistently even though posture control, measured by pelvis and trunk movement, appeared to be significantly challenged. Muscle activation consisted of tonic and variable combinations of muscle pairings in early sitting. As infants progressed to sitting without hand support, variable but successful strategies utilizing lower extremity muscles in a tight linkage with reach onset emerged to provide prospective control for reaching. Our findings support the contention that reaching both drives the development of sitting in infancy as well as perturbs sitting posture, factoring into the assembly of the complex dual sit–reach behavior that supports and expands flexible interaction with the environment.

Crawling to the Finish Line: Why do Endurance Runners Collapse?

Effective regulation of pace enables the majority of runners to complete competitive endurance events without mishap. However, some runners do experience exercise-induced collapse associated with postural hypotension, which in rare cases results from life-threatening conditions such as cardiac disorders, cerebral events, heat stroke and hyponatraemia. Despite the experience of either catastrophic system failure or extreme peripheral muscle fatigue, some runners persist in attempting to reach the finish line, and this often results in a sequence of dynamic changes in posture and gait that we have termed the 'Foster collapse positions'. The initial stage involves an unstable gait and the runner assumes the 'Early Foster' collapse position with hips slightly flexed and their head lowered. This unstable gait further degrades into a shuffle referred to as the 'Half Foster' collapse position characterized by hip flexion of approximately 90° with the trunk and head parallel to the ground. At this point, the muscles of postural support and the co-ordination of propulsion begin to be compromised. If the condition worsens, the runner will fall to the ground and assume the 'Full Foster' collapse position, which involves crawling forwards on knees and elbows towards the finish line, with their trunk angled such that the head is at a lower angle than the hips. Upon reaching the finish line, or sometimes before that, the runner may collapse and remain prone until recovering either with or without assistance or medical treatment. The Foster collapse positions are indicative of a final, likely primordial, protective mechanism designed to attenuate postural hypotension, cardiac 'pump' insufficiency or cerebral blood flow deficiency. Continuing to attempt to reach the finish line in this impaired state is also perhaps indicative of a high psychological drive or a variety of neurological and psychological pathologies such as diminished sensitivity to interoceptive feedback, unrealistic situational appraisal or extreme motivational drives. A better understanding of the physiological, neurological and psychological antecedents of the Foster collapse sequence remains an important issue with practical implications for runner safety and theoretical understanding of collapses during exercise.

Evaluation of the New York Posture Rating Chart for Assessing Changes in Postural Alignment in a Garment Study

The New York Posture Rating (NYPR) was evaluated for assessing postural alignment changes in a garment study as captured in photographs and body scans. The posture of 15 pre-menopausal females aged 40 to 55 were assessed while wearing a control and a posture support garment. The scale was successfully applied with good rater reliability for photographs (0.77) and body scans (0.91). Overall photographic posture assessments were not significant, however, two body segments showed improvement. Overall body scan posture assessments revealed significant improvement for the posture support garment, and improvement in one body segment (neck). Paired t –test comparison of NYPR from photographs and body scans were not significantly different in the posture support garment and significantly different for the control. Possible solutions are discussed. Overall results, support the potential use of the NYPR in studies of garment effects on posture and the body scans as an assessment tool.

Posture support improves object individuation in infants.

A hierarchical progression in infants' ability to use surface features, such as color, as a basis for object individuation in the first year has been well established (Tremoulet, Leslie, & Hall, 2000; Wilcox, 1999). There is evidence, however, that infants' sensitivity to surface features can be increased through multisensory (i.e., visuohaptic) exploration of objects (Wilcox, Woods, Chapa, & McCurry, 2007). Three studies were conducted to investigate the effect of multisensory experience on infants' sensitivity to pattern information. Experiments 1 and 2 confirmed that 5.5- and 6.5-month-olds do not spontaneously use pattern differences to individuate objects and revealed that 6.5- but not 5.5-month-olds can be primed to attend to pattern differences if allowed multisensory experience with the objects prior to the individuation task. However, the 5.5-month-olds also had greater difficulty maintaining a self-sitting posture during the multisensory priming experience. In Experiment 3, 4.5- and 5.5-month-olds were given full postural support during the multisensory exploration period. In this situation, the 5.5-month-olds successfully individuated the objects, but even with full postural support, 4.5-month-old infants did not use the pattern differences to individuate the objects. These results demonstrate that multisensory priming is effective with infants as young as 5.5 months and extends multisensory priming to another surface feature, pattern. Furthermore, these results indicate that constraints are placed on the multisensory experience by the physical and motor development of the infant.

2P1-C12 立位移動を支援する適応的姿勢可変パーソナルモビリティ(福祉ロボティクス・メカトロニクス(3))

This study proposes a novel personal mobility vehicle to support and assist people with disabled lower limbs. The developed mobile platform is capable of assisting transition between standing and sitting. The device consists of an exoskeleton, which is powered by 4 gas springs for postural support and 2 in-wheel motors for the mobility support. The device allows a user to sit down on chairs or beds, and stand up by easy operations. In addition, it can be moved with their standing posture without using their hands. In this paper, the development and assessments of the personal mobility vehicle are described.

Safety, usability, and independence for wheelchair-seated drivers and front-row passengers of private vehicles: A qualitative research study

A survey and observational study was conducted with 29 people who remain seated in their wheelchair when driving (21) or riding as a front-row passenger (8) in their personal vehicle. Each subject was observed and surveyed in their own personal vehicle that has been modified for use by occupants seated in wheelchairs. Our survey obtained responses on issues related to occupant restraint (seat belt) system usage, wheelchair securement device usage, and perception of personal safety while riding in a vehicle. Usability and accessibility issues related to seat belt and automated (docking) wheelchair securement technology were revealed, suggesting that wheelchair-seated occupants travel with a higher risk of serious injury in vehicle crashes than front-row occupants seated in original equipment manufacturer (OEM) vehicle seats and using OEM seat belts. Study results also indicate the need for improved torso support for many wheelchair-seated drivers to maintain a posture that allows for effective vehicle control. Study results demonstrate the need for innovative passive restraint technologies that provide postural support during normal vehicle operation and improved occupant restraint during crash conditions for people who drive while seated in their wheelchairs.

A controlled trial of plyometric training for rhythmic female gymnasts

Background . Plyometrics is a form of training that has proven very effective for many categories of athlete, but there has been little evaluation of this technique in gymnasts. We hypothesized that the performance of well-trained competitive rhythmic gymnasts might be further enhanced by adding a short course of plyometric exercises to their normal regimen. Methods . We tested our hypothesis in a sample of twenty female rhythmic gymnasts aged between 17 and 20 years who had no previous experience of plyometrics. Subjects were divided into equal experimental and control groups. The explosive (squat and countermovement jumps with and without arm movement) and reactive (drop jump and stiffness jumps) forces developed by the lower limbs were analyzed using an Opto-jump device before and after the experimental subjects had completed 12 plyometric training sessions over a period of 4 weeks. Results . Experimental and control groups were initially well-matched. However, after the 4 weeks of plyometric training, ANOVA showed significant gains in the experimental group on all measures except the Vittori index, with development of a large and statistically significant inter-group advantage to the experimental subjects.. Conclusions . The data imply that the plyometric programme induced significant improvements in the explosive force, power and relaxation of the quadriceps and triceps surae in those subjects who followed the plyometric regimen. The qualitative balance of strength between the quadriceps and triceps surae was also improved, as was the quality of postural support. We would thus recommend that such a programme be incorporated into the preparation of all competitive gymnasts, as it is in many other forms of sport.

Joystick stiffness, movement speed and direction effects on upper limb muscular loading

The manipulation of joysticks to control heavy machinery requires repetitive wrist and upper limb movements which can increase operator susceptibility to repetitive strain injuries. The purpose of this study was to analyse muscle activation using surface electromyography (EMG) on eight muscles of the upper limb during joystick manipulation. Experiments (n=8 subjects) involved a series of 4 motion types (forward, backwards, inwards, outwards) at 2 speeds (fast, slow) using 3 identical joysticks with different stiffnesses (light, regular, heavy). Results showed that all experimental conditions required at least a constant low level (between 2–5% Task Maximal Voluntary Contraction) activation for all muscles. The joystick utilized in this study maintains the wrist in a more neutral posture, however, Integrated EMG (iEMG) and peakEMG results suggest that the muscle strain is transferred from the wrist to the shoulder. EMG results also suggest that shoulder strain is further exacerbated by the armrest as it forces the operator to elevate the shoulder while pulling the controller backwards and inadequately supporting the forearm while moving it in the forward direction. Muscles involved as prime movers had higher activation levels when joystick stiffness was increased, however, muscles that provided directional, positional or postural support to the prime movers were relatively unaffected by joystick stiffness. Muscle activation was increased for all muscles when the joystick was moved quickly. This finding may be important for work environments using joysticks which require increased precision and fine movements coupled with short, highly repetitious cycle times.

Factors contributing to extended activity times during the provision of wheeled mobility devices

Purpose: A secondary analysis was performed on data from a recent time-motion study documenting the type and duration of activities performed during the provision of wheeled mobility and seating devices. The objective of this analysis was to report factors that were most associated with activities having extended durations. Method: Activities were categorized as occurring during the visit-preparation, pre-delivery, delivery or follow-up phases of equipment provision. Extended activities were defined as activities at or exceeding the 75th percentile, corresponding to activities exceeding 37.5 min. Logistic regression and Odd Ratio calculations were used to identify factors that were associated with extended encounters with clients. Results: Extended activities were more likely to be associated with Group 4 power chairs, ultra-lightweight wheelchairs and seating systems comprised of a combination of technologies, such as those with postural supports or using made-to measure or custom-molded techniques. Conclusions: Wheelchair and seating system type were more predictive of extended activities compared to diagnostic categories. This result leads us to posit that functional needs – rather than diagnosis – impacts the duration of client encounters and the complexity of the equipment prescribed to the user. The results also indicate that more complex equipment were more likely to require extended encounters than less complex devices in their respective groupings.Implications for RehabilitationThe provision of wheelchairs and seating systems include many types of activities including some which last for extended or lengthy periods of time.Complex equipment were more associated with extended activities compared to client diagnosis meaning that a person’s functional ability influences the complexity of the intervention more than diagnosis.Activities occurring prior to delivery, including assessment and wheelchair assembly, were twice as likely to last an extended time compared to other activities.The activities associated with ultralight weight manual wheelchairs were 8 times more likely to require lengthy activities compared to all other types of wheelchairs.

A EDUCAÇÃO COMO INSTRUMENTO DE PROTEÇÃO AMBIENTAL

This work relates to a reflexive action on education in formal education as an instrument oftransformation of institutional schooling behavior that concerns itself with issues about theprotection of the environment. The history of mankind drives the universe to environmentaldegradation, environmental damage caused by the rampant advancement of new technologies indifferent human activities without the sensitivity to make use of the environment and,consequently, without there being a constant environmental threat. The ideas addressedimportant posture support a broadcast about the environmental education in relation to the roleof education critical and reflective. Here if you want to demonstrate that every effort will onlyhave value when traçarmos goals for improving knowledge and awareness of environmentalcitizenship.

Wheelchair Components and Pulmonary Function in Children with Cerebral Palsy

ABSTRACT Objective: This study investigates the effects of four individual wheelchair components (upper extremity supports, lateral trunk supports, anterior pelvic belt, and 30 degree posterior seat tilt), on pulmonary function in prepubertal children with cerebral palsy (CP). Methods: Participants who range in age from 5–10 years were evaluated using four wheelchair components in six configurations (conditions 1–6) using a planar seating simulator. The Respironics Non Invasive Cardiac Output monitor (NICO) and MasterScreen Impulse Oscillometry System (IOS) measured pulmonary function parameters. Repeated measures ANOVA was used to analyze effect of wheelchair conditions on total airway resistance (RAW ). Results: Eight participants completed the protocol. RAW and minute ventilation (MV) varied with wheelchair condition. Lowest RAW was seen with two upper extremity supports or two lateral trunk supports. Differences were not significant (p = 0.253). Conclusions: The NICO and IOS, independent of participant effort, measured RAW and MV, which varied by wheelchair seating condition. More research is needed with a larger sample to determine seating components' impact on pulmonary function. These methods objectively measured pulmonary function of young children with CP in wheelchairs and could facilitate further research into benefits of wheelchair postural support components.