Postural Balance

To compare the effects of group-based and individual-based motor skill training on motor performance in children with developmental coordination disorder. Design: Randomized controlled pilot intervention study. Subjects/patients: Twenty-three children (4 girls) with developmental coordination disorder (mean age (standard deviation (SD)) 8 years (1 year and 2 months)). Methods: Twelve children were randomly assigned to undergo a motor training programme once a week for 8 consecutive weeks in a group setting, and 11 children received the same training on an individual basis during the same period. Each child was also instructed to perform home exercises on a daily basis. The Movement Assessment Battery for Children (MABC) was used to assess motor ability. Home exercise compliance and parental satisfaction with the programmes were also evaluated. Results: A significant reduction in the MABC total impairment score was found following both group-based (mean-4.4 (SD 5.0), p = 0.003) and individual-based training (mean-5.2 (SD 5.1), p = 0.016). However, the change in total impairment score did not differ significantly between the 2 groups (p = 0.379). There was similarly no significant between-group difference in home exercise compliance (p = 0.288) and parental satisfaction (p = 0.379). Conclusion: Group-based training produced similar gains in motor performance to individual-based training. Groupbased training may be the preferred treatment option due to the associated cost savings.

The human postural system operates on the basis of integrated information from three independent sources: vestibular, visual and somatosensory. It is conceivable that a derangement of any of these systems will influence the overall output of the postural system. The peripheral proprioceptive system or the central processing of proprioceptive information may be altered in chronic low back pain (CLBP). We therefore investigated whether patients with CLBP exhibited an altered postural control during quiet standing. Dynamic posturography was performed by 12 CLBP patients and 12 age-matched controls. Subject's task was to stand quietly on a computer-controlled movable platform under six sensory conditions that altered the available visual and proprioceptive information. While the control of balance was comparable between the two groups across stabilized support surface conditions (1-3), CLBP patients oscillated much more than controls in the anteriorposterior (AP) direction in platform sway-referenced conditions (4-6). Control experiments ruled out that increased sway was due to pain interference. In CLBP patients, postural stability under challenging conditions is maintained by an increased sway in AP direction. This change in postural strategy may underlie a dysfunction of the peripheral proprioceptive system or the central integration of proprioceptive information. #

Posture control appears deeply impaired in patients with severe Acquired Brain Injury (ABI). One of the main goals of neurorehabilitation specialists is to try to assess this neural function in a standardized manner. However, the tests available to evaluate posture control recovery after brain damage were developed for patients with focal neurological signs. We therefore developed a new test, the Trunk Recovery Scale (TRS). To evaluate the inter-rater reliability, internal consistency, external validity, and sensitivity of TRS in patients with ABI. Validation study. We examined 59 patients hospitalized after a brain injury in the Intensive and the Extensive Rehabilitation Units of our hospital. Patients with diagnosis of severe ABI with the capacity to respond to simple verbal orders and with a Level of Cognitive Functioning Scale (LCF scale) ≥ 4. Three raters independently assessed 20 subjects. One of the raters also assessed 39 additional subjects using TRS, Trunk Control Test (TC...

Low back pain affects the person's ability to keep balance, especially in challenging conditions. The purpose of this study was to determine the immediate effects of Pilates exercises on postural sway and dynamic balance of young individuals with non-specific low back pain. Controlled laboratory design. Forty-six participants with non-specific low back pain were randomized to a Pilates (n=23, 10 males; age: 21.8±3.2years) and a control group (n=23, 9 males; age: 22.8±3.6years). Postural sway was assessed with a force platform and dynamic balance with the Star Excursion Balance Test, before and after the intervention or rest period. To assess postural sway, participants stood still on an unstable surface set on the force plate for 90s, with eyes closed. The intervention lasted 20min and consisted on four Pilates exercises: single leg stretch (level 1), pelvic press (level 1), swimming (level 1) and kneeling opposite arm and leg reach. At baseline, no differences were found betwee...

Children with many types of motor dysfunction have problems maintaining postural stability. Because maintenance of postural stability is an integral part of all movements, therapists evaluate and treat to improve postural stability in these children. This article reviews current pediatric assessment tools for postural stability and issues affecting testing this construct in children. The tests and measurements are classified according to their testing purpose and the National Center for Medical Rehabilitation Research disablement framework, focusing on the impairment and functional limitation dimensions. Postural stability is defined from a systems perspective with tests related to the sensory, motor, and biomechanical systems described. Reliability and validity information on the measurements is discussed. Relatively few measurements of postural stability in children are available that have acceptable reliability and validity documentation. Suggestions for research on test development in this area are discussed. [Westcott SL, Lowes LP, Richardson PK. Evaluation of postural stability in children: current theories and assessment tools.

Computerized dynamic platform posturography is defined in this technology assessment. The review discusses what computerized dynamic platform posturography measures, what the reliability and validity of the information are, and the uniqueness of the information provided. The clinical contribution and indications for testing are discussed. There are comments on future directions for research on computerized dynamic platform posturography and a summary and conclusion. (Otolaryngol Head Neck Surg 1997;117:394-8.) DEFINITION Postural sway has long been recognized as an important indicator of balance function. Strain gauges incorporated into force platforms have been used to record postural sway too small to be seen by the unaided observer. Such devices recently have been linked to electronic digital computers to produce computerized dynamic platform posturography (CDPP). In CDPP a force platform is mechanized and digitally controlled so that it either can move in a horizontal plane, that is, translate, or can rotate out of the horizontal plane, that is, pitch the patient either forward or backward. 1-4 CDPP has been combined with visual stimuli to determine the relative importance of vision and somatosensation to balance. Several characteristics are considered necessary for a device to qualify as CDPP in this technology assessment. The device must be capable of measuring postural sway, that is, changes in the center of the patient's applied force. The device must incorporate means of

This study investigated the influence of attention on the sensory integration component of postural control in young and older adults. Eighteen young and 18 older healthy subjects performed information-processing tasks during different postural challenge conditions. Postural conditions included seated, standing on a firm surface, standing on a sway-referenced floor, and standing on a sway-referenced floor while viewing a sway-referenced scene. During each condition, reaction time (RT) was measured during two simple and one inhibitory RT tasks. For the inhibitory task, the time required to inhibit an action was derived, termed the inhibitory time (IT). Performing a RT task was associated with increased postural sway in older subjects, but not in young subjects. The greatest influence of RT task on sway of older subjects was found during the sway-referenced floor/sway-referenced scene condition. Conversely, postural condition had an influence on RT task performance in both young and older subjects. The IT was increased in both young and older subjects only during the sway-referenced floor/scene condition. These results suggest that the sensory integration component of postural control in particular seems to require attention. Further, our data suggest that attentional processes related to inhibitory control are engaged when sensory integration requirements are high.

Objective: To investigate the role of conventional gait training and partial weighte supported treadmill gait training (PWSTT) in improving the balance of patients with Parkinson disease (PD). Design: Prospective randomized controlled design. Setting: National-level university tertiary hospital for mental health and neurosciences. Patients: Sixty patients with PD fulfilling the United Kingdom Brain Bank PD diagnostic criteria were recruited from the neurology outpatient department and movement disorder clinic. Methodology: The patients were randomly assigned into 3 equal groups: (1) a control group only received a stable dosage of dopaminomimetic drugs; (2) a conventional gait training (CGT) group that received a stable dosage of dopaminomimetic drugs and conventional gait training; and (3) a PWSTT group that received a stable dosage of dopaminomimetic drugs and PWSTT with unloading of 20% of body weight. The sessions for the CGT and PWSTT groups were provided for 30 minutes per day, 4 days per week, for 4 weeks (16 sessions). Outcome measures: The Unified Parkinson Disease Rating Scale (UPDRS) motor score, dynamic posturography, Berg Balance Scale, and Tinetti performance-oriented mobility assessment (POMA) were used as main outcome measures. Results: A significant interaction effect was observed in the UPDRS motor score, mediolateral index, Berg Balance Scale, limits of stability (LOS) total score, POMA gait score, and balance score. Post-hoc analysis showed that in comparison with the control group, the PWSTT group had a significantly better UPDRS motor score, balance indices, LOS in 8 directions, POMA gait, and balance score. The CGT group had a significantly better POMA gait score compared with control subjects. Compared with the CGT group, the PWSTT group had a significantly better UPDRS motor score, mediolateral index, POMA gait score, and LOS total score. Conclusion: PWSTT may be a better interventional choice than CGT for gait and balance rehabilitation in patients with PD.

Affective states, anxiety in particular, have been shown to negatively influence human postural control efficiency as measured by posturographic means, while exposure to a full-length mirror image of one's body exerts a stabilizing effect. We tested the hypothesis that body image concerns and preoccupations would relate negatively to this stabilising effect. Sixty-six healthy students, who screened negative for psychiatric disorders, completed rating scales for anxiety, depression and body image concerns. Posturography recordings of body sway were taken under three conditions: with eyes closed, looking at a vertical bar and looking at a full-length mirror. The Eyes Open/Mirror Stabilometric Quotient [EOMQ=(sway path with eyes closed/sway path looking at the mirror)x100], an index of how much postural control is stabilized by mirror feedback in comparison to the visual vertical bar condition, was significantly inversely related to body image concerns and preoccupations, and to trait anxiety. This finding confirms the impact of emotional factors on human postural control, which warrant further studies. If confirmed in clinical populations characterized by high levels of body image disturbances, e.g. eating disorders, it could lead to developments in the assessment and monitoring of these patients.

Repetitive motion-induced fatigue not only alters local motion characteristics but also provokes global reorganization of movement. However, the three-dimensional (3D) characteristics of these reorganization patterns have never been documented in detail. The goal of this study was to assess the effects of repetitive reaching-induced arm fatigue on the whole-body, 3D biomechanical task characteristics. Healthy subjects (N = 14) stood and performed a continuous reaching task (RRT) between two targets placed at shoulder height to fatigue. Whole-body kinematic (Vicon Ó ), kinetic (AMTI Ó force platforms) and electromyographic (EMG, Noraxon Ó ) characteristics were recorded. Maximal voluntary isometric efforts (MVIE) of the shoulder and elbow were measured pre-and post-RRT. Post-RRT shoulder elevation MVIE was reduced by 4.9 ± 8.3% and trapezius EMG amplitude recorded during the RRT increased by 46.9 ± 49.9% from the first to last minute of the RRT, indicating that arm fatigue was effectively induced. During fatigued reaching, subjects elevated their shoulder (11.7 ± 10.5 mm) and decreased their average shoulder abduction angle by 8.3 ± 4.4°. These changes were accompanied by a lateral shift of the body's center of mass towards the non-reaching arm. These findings suggest a compensatory strategy to decrease the load on the fatigued shoulder musculature.

Gait speed, commonly modified to adapt to the balance and stability challenges of aging, is related to measures of balance and mobility. This study investigated associations between age, Berg Balance Scale, Activities-Specific Balance Confidence (ABC) Scale, One Question Fear of Falling (1QFOF), and gait speed in adults using regression analysis. Results suggested an interaction between 1QFOF and ABC scores. An expanded five-variable model explained 49% of gait speed variance. Age, ABC, and 1QFOF-ABC interactions were significantly associated with gait speed.

falls, standing balance and obstacle avoidance performance, and balance confi dence scores. Results: The number of falls in the exercise group decreased by 46% (incidence rate ratio (IRR) 0.54, 95% confi dence interval (CI) 0.36-0.79) compared to the number of falls during the baseline period and by 46% (IRR 0.54, 95% CI 0.34-0.86) compared to the control group. Obstacle avoidance success rates improved signifi cantly more in the exercise group (on average 12%) compared to the control group (on average 6%). Quiet stance and weight-shifting measures did not show signifi cant effects of exercise. The exercise group also had a 6% increase of balance confi dence scores. Conclusion: The Nijmegen Falls Prevention Program was effective in reducing the incidence of falls in otherwise healthy elderly. There was no evidence of improved control of posture as a mechanism underlying this result. In contrast, an obstacle avoidance task indicated that subjects improved their performance. Laboratory obstacle avoidance tests may therefore be better instruments to evaluate future fall prevention studies than posturographic balance assessments.

trol and were sufficient for regaining balance within one gait cycle. The adaptive attenuation of proximal postural activity over repeated trials suggests that the nervous system overcompensates for a novel balance threat in the first slip trial and fine-tunes its responses with experience.

The purpose of the study was to evaluate the effect of BodyBalance ® training on balance, functional task performance, fear of falling, and health-related quality of life in adults aged over 55 years. Participants and methods: A total of 28 healthy, active adults aged 66±5 years completed the randomized controlled trial. Balance, functional task performance, fear of falling, and self-reported quality of life were assessed at baseline and after 12 weeks. Participants either undertook two sessions of BodyBalance per week for 12 weeks (n=15) or continued with their normal activities (n=13). Results: Significant group-by-time interactions were found for the timed up and go (P=0.038), 30-second chair stand (P=0.037), and mediolateral center-of-pressure range in narrow stance with eyes closed (P=0.017). There were no significant effects on fear of falling or self-reported quality of life. Conclusion: Twelve weeks of BodyBalance training is effective at improving certain balance and functional based tasks in healthy older adults.

Objectives: To evaluate and compare the effects and safety of high dose intramuscular (IM) or oral cholecalciferol on 25-hydroxyvitamin D [25(OH)D] levels, muscle strength and physical performance in vitamin D deficient/insufficient elderly. Study design: Randomized prospective study. Main outcome measures: 116 ambulatory individuals aged 65 years or older living in a nursing home were evaluated. Eligible patients with 25(OH)D levels <30 ng/ml (n = 66) were randomized to IM or Oral groups according to the administration route of 600,000 IU cholecalciferol. Demographic and descriptive data were collected. Biochemical response was measured at baseline, 6th and 12th weeks. Muscle strength was measured from quadriceps by using a hand-held dynamometer and physical performance was evaluated by short physical performance battery (SPPB) at the beginning and 12th week. Results: Among the screened ambulatory elderly only 5.2% (n = 6) had adequate vitamin D levels. 37.1% (n = 43) were vitamin D deficient and 57.7% (n = 67) were insufficient. After administration of one megadose of vitamin D, mean serum 25(OH)D levels increased significantly at 6th week (32.72 ± 9.0 ng/ml) and at 12th week (52.34 ± 14.2 ng/ml) compared with baseline (11.76 ± 7.6 ng/ml) in IM group (p < 0.0001). In Oral group levels were 47.57 ± 12.7 ng/ml, 42.94 ± 13.4 ng/ml and 14.87 ± 6.9 ng/ml, respectively (p < 0.0001). At 12th week the increase in IM group was significantly higher than Oral group (p = 0.003). At the end of the study period, serum 25(OH)D levels were ≥30 ng/ml in all patients in IM group and in 83.3% of the patients in the Oral group. Quadriceps muscle strength and SPPB total score increased significantly in both groups and SPPB balance subscale score increased only in IM group. Six patients (9.6%) developed hypercalciuria, no significant adverse events were observed. Conclusion: In vitamin D deficient/insufficient elderly, a single megadose of cholecalciferol increased vitamin D levels significantly and the majority of the patients reached optimal levels. Although both administration routes are effective and appear to be safe, IM application is more effective in increasing 25(OH)D levels and balance performance.

The objective of this study was to evaluate how effective dynamic support-surface posturography could be as a diagnostic tool in patients with balance disorders (proprioceptive or vestibular deficits). Specifically, we studied whether measures of trunk control and simple toe-up rotational perturbations, selected using statistical techniques, could provide a better diagnostic yield than either the analysis of lower-body movements or use of a 'nulled' ankle input paradigm. The test subjects were 15 control subjects, five patients with bilateral peripheral vestibular loss (VL) and five patients with selective bilateral, lower-leg proprioceptive loss (PL). Amplitudes and onset latencies of bursts of EMG activity in upper and lower-leg muscles, paraspinals and trapezius muscles, concurrent changes in ankle torque, and peak amplitudes of upper-leg, lower-leg, and trunk angular-velocities were measured. Stimuli included three different types of sudden movements of the support surface, a 'nulled' ankle input paradigm, a simple toe-up rotation paradigm, and a combined toe-up rotation and backwards translation of the support surface. All stimuli were tested under eyes-open and eyes-closed conditions. For each type of movement and condition the diagnostic classification accuracy (i.e. the overall sensitivity and specificity) was calculated based on those posturography measures providing the highest diagnostic separation between the three populations. Both patient groups showed increased trunk sway, changed support-surface reaction forces and muscle amplitudes compared with controls for toe-up and 'nulled' test conditions. Measures providing the greatest diagnostic utility were the amplitude of trunk-angular velocity (increased in VL subjects, less so in PL), the amplitude of balance-correcting paraspinal responses (increased in VL subjects, decreased in PL subjects), the amplitude of trapezius stabilising responses (increased in both patient groups) for simple toe-up rotations under eyes-closed conditions. We conclude, that diagnosis of balance disorders using dynamic posturography is best achieved using measures of trunk control following pure toe-up rotational perturbations tested under eyes-closed conditions.

Objective: To evaluate balance control with Balance Rehabilitation Unit (BRU TM ) posturography in patients with multiple sclerosis (MS). Method: A cross controlled study was performed including 39 relapsing-remitting multiple sclerosis patients with scores less than or equal to 4 in the Expanded Disability Status Scale (EDSS), and a homogeneous control group consisting of 65 healthy individuals, matched by the age and gender. The experimental group was distributed according to the EDSS scale scores in 0-2.5 and 3-4. To assess the vestibular system function, the patients underwent a neurotological evaluation, including posturography of the Balance Rehabilitation Unit (BRU TM ). Results: Statistically significant differences were observed when comparing the values of the sway velocity and the ellipse area of the MS 0-2.5 group with the control and the MS 3-4 group with the control. A statistically significant difference was verified between the MS 0-2.5 and the MS 3-4 groups in the condition 3 ellipse area values. Conclusion: The evaluation of the balance control with posturography of Balance Rehabilitation Unit (BRU TM ) enables the identification of abnormalities of the sway velocity and confidential ellipse in patients with relapsing-remitting multiple sclerosis.

This study examined how young healthy adults learn stilt walking. Ten healthy male university students attended
two sessions of testing held on two consecutive days. In each session participants performed three blocks of 10 stiltwalking
trials. Angular movements of head and trunk and the spatial and temporal gait parameters were recorded.
When walking on stilts young adults improved their gait velocity through modifications of step parameters while
maintaining trunk movements close to that observed during normal over-ground walking. Participants improved
their performance by increasing their step frequency and step length and reducing the double support percentage
of the gait cycle. Stilts are often used for drywall installation, painting over-the-head areas and raising workers
above the ground without the burden of erecting scaffolding. This research examines the locomotor adaptation
as young healthy adults learn the complex motor task of stilt walking; a task that is frequently used in the
construction industry.

Function-focused care (FFC) is an approach to care in which nurses help patients engage in activities of daily living (ADL) and physical activity, with the goal of preventing avoidable functional decline. This prospective, observational study, conducted with hospitalized older adults (N 5 93) examined: 1) the demographic and clinical characteristics of patients who were provided FFC activity, and 2) the relationship between change in physical activity and FFC activities. Patients who received FFC were more likely: to be younger (P 5 .028); had one or more falls during the hospitalization (P 5 .048); had demonstrated better functional performance at admission (P 5 .004) and better physical capability, measured by the Tinetti gait and balance scale (P 5 .004). FFC was associated with less decrement in ADL function, admission to discharge, while considering patient characteristics (t 5 7.6; P \ .008). Results suggest that hospitalized older persons can benefit from FFC. (Geriatr Nurs 2012;33:272-279) O lder adults are admitted to acute care hospitals at rates as high as 3 times those of younger individuals. 1 It is estimated that up to 50% lose the ability to conduct activities of daily living (ADLs) while hospitalized, 2 with profound implications for their health. The consequences of functional decline include decreased functional recovery 3 and increased morbidity and mortality. 4 The immobility associated with functional decline results in iatrogenic infections, pressure ulcers, falls, and nonelective rehospitalizations. 5,6 Moreover, lack of attention to functional health predisposes the older adult to prolonged, costly rehabilitative care with limited guarantee of return to prehospitalization function. 7 This shortfall in care delivery is inconsistent with the basic tenet of gerontological nursing that emphasizes preservation of function and with the older person's expectation that the hospitalization improve not worsen health and functioning. 8 This study begins to address this gap by examining the interaction between nurses and hospitalized older adults during ADL performance and the relationship with functional outcomes.

The objective of this study was to determine differences in electromyographic (EMG) activity of the soleus (SOL), vastus lateralis (VL), biceps femoris (BF), abdominal stabilizers (AS), upper lumbar erector spinae (ULES), and lumbo-sacral erector spinae (LSES) muscles while performing squats of varied stability and resistance. Stability was altered by doing the squat movement on a Smith machine, a free squat, and while standing on two balance discs. Fourteen male subjects performed the movements. Activities of the SOL, AS, ULES, and LSES were highest during the unstable squat and lowest with the Smith machine protocol (p &lt; 0.05). Increased EMG activity of these muscles may be attributed to their postural and stabilization role. Furthermore, EMG activity was higher during concentric contractions compared to eccentric contractions. Performing squats on unstable surfaces may permit a training adaptation of the trunk muscles responsible for supporting the spinal column (i.e., erector...

Movement is performed against a background of subtle postural adjustments that counteract destabilizing forces imposed by the movement. Despite the importance of these postural adjustments to the safe and efficient performance of movement, little is known about the properties of these postural accompaniments. The purpose of this article is twofold. First, it provides a review of properties of postural adjustments that accompany a variety of limb and trunk movements. Second, a schema for the coordination of posture and movement is proposed. This schema suggests that a central nervous system model of body dynamics is essential to anticipatory control of posture during movement.

Objective: The primary aim of this study was to compare the motor performance of physically well-recovered men with traumatic brain injury with that of healthy men. Design: Cross-sectional study in a national rehabilitation centre. Methods: Static and dynamic balance, agility and rhythm co-ordination of men with traumatic brain injury (n /34) and healthy controls (n /36) were assessed. Between-group differences in dynamic balance and agility were analysed by analysis of covariance and differences in static balance and rhythm co-ordination by logistic regression analysis. Cut-off points for clinical screening were determined by receiver operating characteristics analyses. Results: Men with traumatic brain injury had impaired balance and agility compared with healthy men and in a rhythm co-ordination test they had difficulties in starting and sustaining simultaneous rhythmical movements of hands and feet. In receiver operating characteristics analyses a running figure-of-eight test (agility), tandem walking forwards (dynamic balance) and rhythm co-ordination test with fast tempo were found the most sensitive and specific for distinguishing between men with traumatic brain injury and the healthy men. Conclusions: The impairments in motor performance of physically well-recovered patients with traumatic brain injury were obvious. The results of this study extend the knowledge of problems in motor performance among patients with traumatic brain injury and provide further information for clinical rehabilitation. (MMSE; normal /24/30), which is a widely used method for assessing cognitive status in adults, testing orientation, attention, immediate and short-term recall, language, and ability to follow simple verbal and written commands (12); and they were able (iv ) to maintain initial test positions; (v ) to perform a 2 km Walk Test developed at UKK Institute (13); and (vi ) to run a short distance. In addition, for the subjects with TBI, more than one year should have passed since the J

This study focused on the phase between the time of straightened pole and the maximum height (HP) of vaulter and aimed at determining the catapult effect in pole vaulting on HP. Seven experienced vaulters performed 5-10 vaults recorded by two video cameras, while the surface electromyography (sEMG) activity of 10 upper limbs muscles was recorded. HP was compared with an estimated maximum height (HP est ) allowing the computation of a push-off index. Muscle synergies were extracted from the sEMG activity profiles using a non-negative matrix factorization algorithm. No significant difference (p > 0.47) was found between HP est (4.64 ± 0.21 m) and HP (4.69 ± 0.23 m). Despite a high interindividual variability in sEMG profiles, two muscle synergies were extracted for all the subjects which accounted for 96.1 ± 2.9% of the total variance. While, the synergy activation coefficients were very similar across subjects, a higher variability was found in the muscle synergy vectors. Consequently, whatever the push-off index among the pole vaulters, the athletes used different muscle groupings (i.e., muscle synergy vectors) which were activated in a similar fashion (i.e., synergy activation coefficients). Overall, these results suggested that muscle coordination adopted between the time of straightened pole and the maximum height does not have a major influence on HP.

Full article available online at ORTHOSuperSite.com. Search: 20111122-14 Orthopedic patients are often instructed on how much weight to bear on an injured or postoperative extremity. Although specifi c weight-bearing instructions are given to a majority of lower-extremity orthopedic patients, the ability of patients to comply with these instructions is questioned in the medical literature. This study compared the effectiveness of new forms of clinical interventions designed to train patients on weight bearing, focusing on the use of biofeedback devices designed to offer real-time feedback to partial weight-bearing patients. Twenty healthy patients aged 20 to 30 years completed 3 interventions: (1) verbal instructions on weight bearing, (2) training with a bathroom scale, and (3) training with a biofeedback device. Patients given touchdown weight-bearing instructions (25 lb) initially bore an average of 63.57Ϯ6.24 lb when given verbal instructions. This was reduced to 44.75Ϯ5.69 lb after training with a bathroom scale (PϽ.001), and was further reduced to 26.2Ϯ1.57 lb with biofeedback training (Pϭ.011). Likewise, patients given partial weight-bearing instructions (75 lb) initially bore an average of 92.28Ϯ7.85 lb. No improvement occurred with the use of a bathroom scale (at 75 lb), which showed an average of 90.82Ϯ7.19 lb (Pϭ1.000). Training with a biofeedback device improved the average weight bearing to 69.67Ϯ3.18 lb (Pϭ.014). Biofeedback training led to superior compliance with touchdown and partial weightbearing instructions. Because partial weight-bearing instructions are commonly given to orthopedic patients, training with such a device may be appropriately considered.

Contralateral transversus abdominis muscle (cTrA) is known to be anticipatory to rapid focal movement. The activation of ipsilateral TrA (iTrA) follows cTrA, but their anticipatory interaction in healthy subjects seems to be delayed in low back pain (LBP) patients. TrA delay in LBP is linked with reorganization of the primary motor cortex (M1), thus supporting that cortical changes underlie the altered postural control. Our study tested whether differences in postural adjustments were present in LBP for TrA onsets and co-activation, and whether these differences were paralleled by cortical motor changes. Thirteen chronic LBP patients and 9 healthy Controls were enrolled. Surface recordings of cTrA/internal oblique (IO) and iTrA/IO were collected during a rapid shoulder flexion task while standing. Transcranial magnetic stimulation of M1 tested TrA/IO corticospinal excitability, active motor threshold and short-interval intracortical inhibition (SICI). In LBP compared to Controls, iTrA/IO activation was delayed, co-activation was absent, timing between TrA/IO onsets was impaired, and SICI was missing. Betweenoutcomes correlations observed in one group were not significant in the other. Delay of iTrA/IO and the lacking co-activation were not explained by between-group differences of transcranial magnetic stimulation outcomes. TrA/IO co-activation is present during rapid focal movement in healthy subjects only. LBP patients displayed an important alteration of the control of spine stability that can be explained by altered mechanisms of M1 motor programming.

We compared anteroposterior and mediolateral range of motion and velocity of the center of pressure (COP) on the horse's back between riders without disabilities and riders with cerebral palsy. An electronic pressure mat was used to track COP movements beneath the saddle in 4 riders without disabilities and 4 riders with cerebral palsy. Comparisons between rider groups were made using the Mann-Whitney test (p < .05). The two rider groups differed significantly in anteroposterior range of COP motion, mediolateral range of COP motion, and mediolateral COP velocity. Anteroposterior COP velocity did not differ between groups. The results suggest that measurements of COP range of motion and velocity are potentially useful for monitoring changes in balance as an indicator of core stability during equine-assisted activities.

Abnormal or excessive force on the anterior hip joint may cause anterior hip pain, subtle hip instability and a tear of the acetabular labrum. We propose that both the pattern of muscle force and hip joint position can affect the magnitude of anterior joint force and thus possibly lead to excessive force and injury. The purpose of this study was to determine the effect of hip joint position and of weakness of the gluteal and iliopsoas muscles on anterior hip joint force. We used a musculoskeletal model to estimate hip joint forces during simulated prone hip extension and supine hip flexion under 4 different muscle force conditions and across a range of hip extension and flexion positions. Weakness of specified muscles was simulated by decreasing the modeled maximum force value for the gluteal muscles during hip extension and the iliopsoas muscle during hip flexion. We found that decreased force contribution from the gluteal muscles during hip extension and the iliopsoas muscle during hip flexion resulted in an increase in the anterior hip joint force. The anterior hip joint force was greater when the hip was in extension than when the hip was in flexion. Further studies are warranted to determine if increased utilization of the gluteal muscles during hip extension and of the iliopsoas muscle during hip flexion, and avoidance of hip extension beyond neutral would be beneficial for people with anterior hip pain, subtle hip instability, or an anterior acetabular labral tear.

Circadian variation of physiological functions related to physical work capacity. by Ilmarinen J, Ilmarinen R, Korhonen O, Nurminen M ILMARINEN J, ILMARINEN R, KORHONEN 0, NURMINEN M. Circadian variation of physiological functions related to physical work capacity. Scand j work environ health 6 (1980) 112-122. The circadian variation of selected physiological functions related to physical work capacity was studied in four trained y~)Ung male subjects. The twofold objective was to describe, in parametric terms, the variation of these functions and estimate the times and values of their maximum and minimum responses. Statistically significant periodic regression effects were found for the following functions: oral temperature; systolic blood pressure; heart rate at rest, during work (245 and 270 W) and after a 5-min recovery; ratings of perceived exertion; strength of hand grip; and neuromuscular coordination measured with a seesaw board balance test. The Fourier curve (sine curve) accounted for 63 % of the variation in oral temperature and from 13 to 38 % of the variation in the other signiIficant harmonic intensities. In phase with the rhythm of oral temperature, but with larger amplitude, were systolic blood pressure, heart rate at rest and heart rate during work; roughly in phase were strength of hand grip and neuromuscular coordination. Rating-s of perceived exertion and heart rate after a 5-min recovery showed a rhythm which was out of phase with the oral temperature. The number of distur,bances in neuromuscular coordination was greatest at 2400 and smallest at 1200, the difference being as large as 44 0/0• The results suggest that the measured capacities of muscle strength and neuromuscular coordination are the lowest, that physical work is perceived as the heaviest, and recovery after work is the slowest at night. These findings appear to support the notion that performance capacity is reduced during the night.

In the present study, we examined the effects of the time lag between visual scene and the head movement in the virtual reality (VR) world on motion sickness and postural control in healthy volunteers. After immersion in VR with additional time lags (from 0 to 0.8 s) to the inherent delay (about 250 ms), the visual-vestibular conflict induced a slight motion sickness in experimental subjects, but no change was noticed in the body sway path with eyes open and closed. However, Romberg ratio of body sway path with eyes closed divided by that with eyes open after immersion in VR was significantly decreased in comparison with that before immersion in VR. Since Romberg ratio is an index of visual dependency on postural control, this finding indicates that the immersion in VR decreases the visual dependency on postural control. It is suggested that adaptation to visual-vestibular conflict in VR immersion increases the contribution of vestibular and somatosensory inputs to postural control by ignoring the conflicting delayed visual input in the VR world. VR may be a promising treatment for visual vertigo in vestibular patients with unsuccessful compensation by its ability to induce vestibular and somatosensory reweighing for postural control.

In an effort to further our understanding of postural control in Parkinson's disease, we biomechanically evaluated the sit to walk task and its component tasks, sit to stand (STS) and gait initiation (GI) in 12 healthy older adults and 12 persons with Parkinson's disease (PWP). Performance was evaluated utilizing motion capture and two force plates. The major finding of this study was the inability of the PWP to appropriately merge the sequential component tasks (STS and GI) during STW. The PWP rose to nearly full height and had a longer delay between seat-off and gait initiation (P 5 0.003 and P < 0.001, respectively) during STW. Additionally, the PWP moved with slower velocities leading to shorter, slower steps and decreased separation of the center of mass and center of pressure. These observed motor sequencing disturbances may be due to a disease related disability or limitations in proprioception, movement speed, muscular strength, and reduced general mobility.

Older adults with type 2 diabetes have mobility impairment and reduced fitness. This study aimed to test the efficacy of the &quot;Tai Chi for Diabetes&quot; form, developed to address health-related problems in diabetes, including mobility and physical function. Thirty-eight older adults with stable type 2 diabetes were randomized to Tai Chi or sham exercise, twice a week for 16 weeks. Outcomes included gait, balance, musculoskeletal and cardiovascular fitness, self-reported activity and quality of life. Static and dynamic balance index (-5.8 +/- 14.2; p = 0.03) and maximal gait speed (6.2 +/- 11.6%; p = 0.005) improved over time, with no significant group effects. There were no changes in other measures. Non-specific effects of exercise testing and/or study participation such as outcome expectation, socialization, the Hawthorne effect, or unmeasured changes in health status or compliance with medical treatment may underlie the modest improvements in gait and balance observed in th...

Postural control is often assessed by quantifying the magnitude of the center of pressure (COP) movement. However, these measures usually focus on the gross amount of movement and ignore the temporal structure of the COP signal. A novel non-linear analysis technique was recently developed to characterize the temporal structure of the COP signal with an output termed the entropic half-life [E(1/2)]. The E(1/2) reflects how much of the previous postural position is used to determine the current postural control strategy (memory effect). The purpose of this study was to quantify the E(1/2) and four COP movement magnitude measurements (medio-lateral and anterior-posterior excursion, path length, 95% ellipse area) for balance tasks increasing in sensory difficulty, as well as the test-retest reliability of each measure. Twenty-seven healthy young adults completed single limb stance tasks varying in sensory difficulty (rigid surface eyes open, rigid surface eyes closed, foam surface eyes open) on two separate occasions. Relative reliability was assessed using an intraclass correlation coefficient (ICC 3,3 ). Absolute reliability was assessed using the standard error of the measurement (SEM) and the sensitivity of the measurement to true changes was assessed using the minimal detectable change (MDC 95 ). The E(1/2) was found to have excellent reliability for all tasks tested (ICC range 0.82-0.91, SEM range 3.5-14.1 mm, MCD 95 range 9.7-39.2 mm). The high reliability of the E(1/2) was comparable to that of movement magnitude measurements. This may be used in order to better understand the underlying motor control system.

Electromyographic (EMG) patterns of the trunk muscles were investigated during balance perturbations in a sitting position. Five healthy subjects (two females and three males, mean age 24.4 yr) were seated on a platform allowing rotational perturbations in the frontal and sagittal planes. Each of the forward, backward, right and left perturbations were delivered with and without expectation at the velocities 8°s Ϫ 1 (SD ± 4°s Ϫ 1 ) and 26°s Ϫ 1 (SD ± 6°s Ϫ 1 ). The fast expected and unexpected perturbations were compared in blindfolded subjects. In the slow perturbations the effect of a blindfold on the balance reactions was tested. The root mean square (RMS) EMG signals from 12 trunk muscles were recorded and analysed to determine the EMG magnitudes. During the forward and backward rotations there was always a symmetrical EMG pattern between corresponding muscles on the right and left sides. A reciprocal phasic EMG activity between the left and right back muscles was found during frontal rotations. No reciprocal phasic activity was found in the abdominal muscles. Neither verbal instruction about the upcoming perturbation nor the blindfold changed the activation patterns.

The purpose of this case report is to describe the responses of 4 patients with chronic heart failure (CHF) to a novel rehabilitation program: a group-based, high-intensity, interval-training program that includes aerobic, resistance, flexibility, and balance activities.

The paper presents a novel control approach for the robot-assisted motion augmentation of disabled subjects during the standing-up manoeuvre. The main goal of the proposal is to integrate the voluntary activity of a person in the control scheme of the rehabilitation robot. The algorithm determines the supportive force to be tracked by a robot force controller. The basic idea behind

This study examined the effect of the handball warm-up program (HWP) on dynamic balance among elite adolescent handball players. In this case, 24 handball players were randomly assigned into experimental warm-up and control groups. The HWP was performed over 8 weeks (3 times per week). Dynamic balance before and after the intervention training programs were measured by the Biodex Balance System (BBS) and Y Balance test for the dominant (DL) and non-dominant legs (non-DL). After HWP training, BBS scores significantly improved in the overall (OSI) (30.4% and 31.1%), anterior-posterior (APSI) (44.6% and 35.2%), and medial-lateral stability indexes (MLSI) (38.8% and 43%) for both DL and non-DL. Post-training, the Y Balance test exhibited significant improvements in OSI (13.2% and 10.6%), anterior (17.2% and 12.6%), posteriolateral (12.8% and 11.3%), and posteriomedial stability indexes (9.2% and 7.9%) with DL and non-DL, respectively. In conclusion, dynamic balance improved overall afte...

Postural adjustments associated with the task of rising on tiptoes were investigated in a reaction time paradigm in 10 normal subjects and 18 patients with cerebellar disorders. Cerebellar dysfunction was due to either degenerative cerebellar disease, tumor, or ischemia. Displacements of the center of foot pressure (CFP) were recorded. The task, accomplished by the triceps surae muscle (executional activity, mean latency of 41 1 ms), is mechan

Acromegaly is a chronic debilitating disease that presents with multiple systemic manifestations, including changes in body composition, joint abnormalities, muscular impairment and visual disturbances. This study aimed to assess posture and body balance in acromegalic patients and to establish the correlation between these measures. Twenty-eight acromegalic patients and a similar number of control subjects matched for sex, age, weight, height and body mass index underwent postural evaluation using the photogrammetry and measurement of balance using the stabilometry in two tasks: feet apart, eyes open and feet together, eyes closed. In comparison with the control group, the acromegalic group presented postural deviations in lateral views in the vertical alignment of the trunk (P = 0.001 for the right side and P = 0.021 for the left), the hip angle (P = 0001 for the right side and P = 0.016 for the left side) and horizontal alignment of the pelvis (P = 0.017 for the right and P < 0.001 for the left side). Compared with healthy subjects, the acromegalic patients presented displacement of the centre of pressure in both the anterior-posterior direction and the medial-lateral direction in both evaluated tasks. We observed significant correlations between balance measures and the following posture evaluation variables: distance between the lower limbs, horizontal alignment of the head and vertical alignment of the head. Our results suggest that posture and balance need to be evaluated for acromegalic patients in clinical practice, as there are significant postural imbalances and deviations in these patients.