Philippe P. Perrin

Judo, better than dance, develops sensorimotor adaptabilities involved in balance control

OBJECTIVES Training allows sportsmen to acquire new balance control abilities, possibly differing according to the discipline practised. We compared, by means of static and dynamic posturographic tests, the postural skills of high-level judoists, professional dancers and controls, in order to determine whether these sports improved postural control. RESULTS With eyes open, judoists and dancers performed better than controls, indicating a positive effect of training on sensorimotor adaptabilities. Yet, with eyes closed, only judoists retained a significantly better stance. CONCLUSIONS These data indicate that the practice of a high-skill activity involving proprioceptive afferences especially improves both performance and balance control.

Effects of physical and sporting activities on balance control in elderly people.

OBJECTIVE: Balance disorders increase with aging and raise the risk of accidental falls in the elderly. It has been suggested that the practice of physical and sporting activities (PSA) efficiently counteracts these age related disorders, reducing the risk of falling significantly. METHODS: This study, principally based on a period during which the subjects were engaged in PSA, included 65 healthy subjects, aged over 60, who were living at home. Three series of posturographic tests (static, dynamic with a single and fast upward tilt, and dynamic with slow sinusoidal oscillations) analysing the centre of foot pressure displacements or electromyographic responses were conducted to determine the effects of PSA practice on balance control. RESULTS: The major variables of postural control were best in subjects who had always practised PSA (AA group). Those who did not take part in PSA at all (II group) had the worst postural performances, whatever the test. Subjects having lately begun PSA practice (IA group) had good postural performances, close to those of the AA group, whereas the subjects who had stopped the practice of PSA at an early age (AI group) did not perform as well. Overall, the postural control in the group studied decreased in the order AA > IA > AI > II. CONCLUSIONS: The period during which PSA are practised seems to be of major importance, having a positive bearing on postural control. It seems that recent periods of practice have greater beneficial effects on the subjects postural stability than PSA practice only at an early age. These data are compatible with the fact that PSA are extremely useful for elderly people even if it has not been a lifelong habit.

Influence of visual control, conduction, and central integration on static and dynamic balance in healthy older adults

Aging is associated with decreased balance abilities, resulting in an increased risk of fall. In order to appreciate the visual, somatosensory, and central signals involved in balance control, sophisticated methods of posturography assessment have been developed, using static and dynamic tests, eventually associated with electromyographic measurements. We applied such methods to a population of healthy older adults in order to appreciate the respective importance of each of these sensorial inputs in aging individuals. Posture control parameters were recorded on a force-measuring platform in 41 healthy young (age 28.5 +/- 5.9 years) and 50 older (age 69.8 +/- 5.9 years) adults, using a static test and two dynamic tests performed by all individuals first with eyes open, then with eyes closed. The distance covered by the center of foot pressure, sway area, and anteroposterior oscillations were significantly higher, with eyes open or closed, in older people than in young subjects. Significant differences were noted in dynamic tests with longer latency responses in the group of old people. Dynamic recordings in a sinusoidal test had a more regular pattern when performed eyes open in both groups and evidenced significantly greater instability in old people. These data suggest that vision remains important in maintaining postural control while conduction and central integration become less efficient with age.

Five times sit to stand test is a predictor of recurrent falls in healthy community-living subjects aged 65 and older.

in nonrenal anemia. A study of 1,005 subjects aged 65 and older demonstrated that the endogenous erythropoietin response is sluggish with age and decline in renal function, contributing to anemia. The findings in Table 1 lend some credibility to the fact that chronic anemia in the Agnihotri et al. study may have been, at least in part, secondary to CKD, in which the endogenous erythropoietin response to declining hemoglobin is known to be blunted, but the response to recombinant epoetin alfa therapy is favorable. In summary, many patients in the study, with a mean age in the 70s, may conceivably have had CKD of varying severity (with or without additional comorbid conditions that cause chronic anemia), and their favorable response to epoetin alfa was to be expected. However, the relatively larger doses of epoetin used (20–40,000 U weekly) bring into consideration the presence of factors that cause resistance to epoetin. Once hemoglobin increases in response to epoetin alfa, better QOL (and less fatigue) likely follows. Analyzing the data in Table 1 further, one would like to know which category of patients (based on GFR, normal versus CKD Stages 1 to 4, ferrokinetics, and non-renal anemias) had a better or poorer response to epoetin and accordingly an effect on QOL. Is it ‘‘chronic anemia’’ (of any etiology, based on the higher doses of epoetin used), or is it ‘‘anemia of CKD,’’ one cause of anemia of chronic disease, that responded favorably to epoetin therapy and improved QOL? These specific conclusions from the present study may have important implications for management of chronic anemia; the cause of anemia does matter!

Posturography and Risk of Recurrent Falls in Healthy Non-Institutionalized Persons Aged Over 65

Background: A poor postural stability in older people is associated with an increased risk of falling. The posturographic tool has widely been used to assess balance control; however, its value in predicting falls remains unclear. Objective: The purpose of this prospective study was to determine the predictive value of posturography in the estimation of the risk of recurrent falls, including a comparison with standard clinical balance tests, in healthy non-institutionalized persons aged over 65. Methods: Two hundred and six healthy non-institutionalized volunteers aged over 65 were tested. Postural control was evaluated by posturographic tests, performed on static, dynamic and dynamized platforms (static test, slow dynamic test and Sensory Organization Test [SOT]) and clinical balance tests (Timed ‘Up & Go’ test, One-Leg Balance, Sit-to-Stand-test). Subsequent falls were monitored prospectively with self-questionnaire sent every 4 months for a period of 16 months after the balance testing. Subjects were classified prospectively in three groups of Non-Fallers (0 fall), Single-Fallers (1 fall) and Multi-Fallers (more than 2 falls). Results: Loss of balance during the last trial of the SOT sensory conflicting condition, when visual and somatosensory inputs were distorted, was the best factor to predict the risk of recurrent falls (OR = 3.6, 95% CI = 1.3–10.11). Multi-Fallers showed no postural adaptation during the repetitive trials of this sensory condition, contrary to Non-Fallers and Single-Fallers. The Multi-Fallers showed significantly more sway when visual inputs were occluded. The clinical balance tests, the static test and the slow dynamic test revealed no significant differences between the groups. Conclusion: In a sample of non-institutionalized older persons aged over 65, posturographic evaluation by the SOT, especially with repetition of the same task in sensory conflicting condition, compared to the clinical tests and the static and dynamic posturographic test, appears to be a more sensitive tool to identify those at high-risk of recurrent falls.

Influence of Different Types of Progressive Idiopathic Scoliosis on Static and Dynamic Postural Control

Study Design. Balance control assessment of static and dynamic conditions was performed to study the effects of progressive idiopathic scoliosis on postural control in 102 adolescents. Objective. To determine how the type and location of idiopathic scoliosis may affect global balance control. Summary of Background Data. Idiopathic scoliosis may impair postural control components, but the repercussions for global balance are relatively mild. Methods. The following four different types of idiopathic scoliosis were compared: thoracic (n = 36), thoracolumbar (n = 22), lumbar (n = 23), and double major (n = 21) curves. Center of foot pressure displacements and electromyographic responses were recorded using static and dynamic posturographic tests (single and fast upward tilt, slow sinusoidal oscillations). Results. The major criteria of postural control were better in the double major group for all the tests. In the static test, the patients with high major curves performed better than those with low major curves. In the fast dynamic test, similar latency values were observed in all the groups. In the slow dynamic test, better results were observed for the patients with low major curves. Conclusions. These data demonstrate that idiopathic scoliosis indeed alters balance control, with different hierarchies, from the best to the worst as follows: double major, thoracic, thoracolumbar, and lumbar curves in the static test and double major, lumbar, thoracolumbar, and thoracic curves in the slow dynamic test. The location of the major curve appeared to be important, with an effect on lateral disequilibrium and vestibular symmetry. The absence of anomaly in the fast dynamic test suggests that the type of scoliosis does not impair proprioception.

Beneficial effect of proprioceptive physical activities on balance control in elderly human subjects.

Age and lack of physical activities may both be responsible for poor balance control. Conversely, physical activities may modulate postural control in elderly individuals. We examined which type of exercise might prove most beneficial to retain or regain proper balance. Nineteen healthy subjects, aged over 60, regularly practicing proprioceptive (group I) or bioenergetic (group II) physical activities and 21 controls only walking on a regular basis, were studied. All were submitted to a dynamic posturographic test and to a test evaluating lower limbs muscular strength. Control individuals displayed the poorest balance and muscular performance. Group I subjects had the best postural control with average muscular strength. In group II, muscular strength was significantly increased, but balance control was of poor quality. Proprioceptive exercise therefore appears to have the best impact on balance control.

Dental occlusion modifies gaze and posture stabilization in human subjects

Repercussion of dental occlusion was tested upon postural and gaze stabilization, the latter with a visuo-motor task evaluated by shooting performances. Eighteen permit holders shooters and 18 controls were enrolled in this study. Postural control was evaluated in both groups according to four mandibular positions imposed by interocclusal splints: (i) intercuspal occlusion (IO), (ii) centric relation (CR), (iii) physiological side lateral occlusion and (iv) controlateral occlusion, in order to appreciate the impact of the splints upon orthostatism. Postural control and gaze stabilization quality decreased, from the best to the worst, with splints in CR, IO and lateral occlusion. In shooters, the improvement in postural control was parallel to superior shooting performance. A repercussion of dental occlusion upon proprioception and visual stabilization is suggested by these data.

Mood states and anxiety influence abilities to maintain balance control in healthy human subjects

Previous studies have shown that anxiety and balance disorders could be related; however, the association between psychological processes and equilibrium remains ambiguous. In this study, we have examined whether mood states and anxiety may influence the ability to use the somatosensory, visual and vestibular systems and affect balance control in healthy subjects. Seven male students were submitted to a program testing equilibrium over a 12-day period, during which moods and anxiety states were assessed using self-evaluated questionnaires. Significant negative correlations were found between moods, including anxiety, and the subjects sensory and motor systems of balance control, suggesting that low moods may alter balance performance. However, depending on the type of mood, it is likely that adverse changes in mood states may affect balance in different ways, either through the sensory organization or motor control.

A Simple Clinical Scale to Stratify Risk of Recurrent Falls in Community-Dwelling Adults Aged 65 Years and Older

Background Correct identification of people at risk for recurrent falls facilitates the establishment of preventive and rehabilitative strategies in older adults. Objective The purposes of this study were: (1) to develop and validate a simple clinical scale to stratify risk for recurrent falls in community-dwelling elderly people based on easily obtained social and clinical items and (2) to evaluate the added value of 3 clinical balance tests in predicting this risk. Design This was a prospective measurement study. Methods A population of 1,618 community-dwelling people over 65 years of age underwent a health checkup, including performance of 3 clinical balance tests: the One-Leg-Balance Test, the Timed “Up & Go” Test, and the Five-Times-Sit-to-Stand Test. Falls were recorded using a self-administered questionnaire that was completed a mean (SD) of 25±5 months after the visit. Participants were randomly divided into either group A (n=999), which was used to develop the scale, or group B (n=619), which was used to prospectively validate the scale. Results Logistic regression analysis identified 4 variables that independently predicted recurrent falls in group A: history of falls, living alone, taking ≥4 medications per day, and female sex. Thereafter, 3 risk categories of recurrent falls (low, moderate, and high) were determined. Predicted probability of recurrent falls increased from 4.1% to 30.1% between the first and third categories. This scale subsequently was validated with great accuracy in group B. Only the Five-Times-Sit-to-Stand Test provided added value in the estimation of risk for recurrent falls, especially for the participants who were at moderate risk, in whom failure on the test (duration of >15 seconds) doubled the risk. Limitations Falls were assessed only once, and length of follow-up was heterogeneous (18–36 months). Conclusions Clinicians could easily classify older patients in low-, moderate-, or high-risk groups of recurrent falls by using 4 easy-to-obtain items. The Five-Times-Sit-to-Stand Test provides added value to stratify risk for falls in people at moderate risk.