Young Adults Largely Depend on Vision for Postural Control When Standing on a BOSU Ball but Not on Foam.

What happens at the sensory level when a person is balancing on compliant surfaces? Compliant surfaces such as both-sides-up (BOSU) balls are often used as a form of "proprioceptive exercises." Clinical theories in neurorehabilitation suggest that compliant surfaces disrupt the somatosensory contribution to balance and increase reliance on vision and vestibular input. Understanding the sensory aspects of compliant surfaces' exercises would have important implications for balance training of athletes and of people with somatosensory deficits such as people with recurrent ankle sprains. We tested this clinical theory in a sample of 30 healthy young adults and 10 adults with a history of repeated ankle sprains while they were standing on a BOSU ball, memory foam, or floor. We measured participants' center of pressure response to dots projected on a screen, moving mediolaterally at one of the 3 frequencies (0.4, 0.48, and 0.56 Hz). We calculated magnitude of the postural response (gains) and participants' primary frequency (PF) of sway and compared it between surfaces per frequency. In both groups, gains were significantly higher on the BOSU compared with floor or foam (p < 0.001) with no significant difference between floor and foam. The PF difference was significant (p < 0.001) with a clear peak matching of the visual stimulation frequency only on the BOSU. During a single session of stance on compliant surfaces, visual dependence was a dominant factor on a challenging condition. When prescribing BOSU exercises to young adults as specific balance training, trainers should consider its effect on increased visual dependence with respect to that session's goals.

Statistical analysis of clinical prediction rules for rehabilitation interventions: current state of the literature.

Deriving clinical prediction rules (CPRs) to identify specific characteristics of patients who would likely respond to certain interventions has become a research priority in physical rehabilitation. Understanding the appropriate statistical principles and methods of analyses underlying the derivation of CPRs is important for future rehabilitation research and clinical applications. In this article, we aimed to provide an overview of statistical techniques used for the derivation of CPRs to predict success following physical therapy interventions and to generate recommendations for improvements in CPR derivation research and statistical analysis in rehabilitation. We have summarized the current state of CPR intervention-related research by reviewing 26 studies. A common technique was found in most studies and included univariate association of factors with treatment success, stepwise logistic regression to determine the most parsimonious set of predictors for success, and calculation of accuracy statistics (focusing on positive likelihood ratios). We identified several shortcomings related to inadequate ratio of events by number of predictors, lack of standardization regarding acceptable interobserver reliability of predictors, questionable handling of predictors including reliance on univariate analysis and early categorization, and not accounting for dependence and collinearity of predictors in multivariable model construction. Interpretation of the derived CPRs was found to be difficult due to lack of precision of estimates and paradoxical findings when a subset of the predictors yielded a larger positive likelihood ratio than did the full set of predictors. Finally, we make recommendations regarding how to strengthen the use of statistical principles and methods to create consistency across rehabilitation research for CPR derivations.

Investigation of the Dynamic Gait Index in children: a pilot study.

PURPOSE: We investigated the feasibility and construct validity of the Dynamic Gait Index (DGI) in children and explored interrater and test-retest reliability. METHODS: DGI performance of 10 children with fetal alcohol spectrum disorder (FASD), aged 8 to 15 years, was compared with that of 10 age- and sex-matched children with typical development (TD). Interrater reliability was evaluated for 16 children (10 TD, 6 FASD); 11 children returned for a retest (5 TD, 6 FASD). RESULTS: The DGI is simple for raters to learn and easy to administer in children. A Mann-Whitney U test identified a significant difference on the DGI total score between children with FASD and TD (P = .01). Interrater and test-retest reliability were promising but need to be further explored. CONCLUSIONS: The DGI was feasible and valid in a population of children aged 8 to 15 years with FASD and TD. Some modifications are suggested for administration of the DGI in children.

The effect of balance training on balance performance in individuals poststroke: a systematic review.

BACKGROUND AND PURPOSE: Stroke is a leading cause of long-term disability, and impaired balance after stroke is strongly associated with future function and recovery. Until recently there has been limited evidence to support the use of balance training to improve balance performance in this population. Information about the optimum exercise dosage has also been lacking. This review evaluated recent evidence related to the effect of balance training on balance performance among individuals poststroke across the continuum of recovery. On the basis of this evidence, we also provide recommendations for exercise prescription in such programs. METHODS: A systematic search was performed on literature published between January 2006 and February 2010, using multiple combinations of intervention (eg, "exercise"), population (eg, "stroke"), and outcome (eg, "balance"). Criteria for inclusion of a study was having at least 1 standing balance exercise in the intervention and 1 study outcome to evaluate balance. RESULTS: Twenty-two published studies met the inclusion criteria. We found moderate evidence that balance performance can be improved following individual, "one-on-one" balance training for participants in the acute stage of stroke, and either one-on-one balance training or group therapy for participants with subacute or chronic stroke. Moderate evidence also suggests that in the acute stage, intensive balance training for 2 to 3 times per week may be sufficient, whereas exercising for 90 minutes or more per day, 5 times per week may be excessive. DISCUSSION AND CONCLUSIONS: This review supports the use of balance training exercises to improve balance performance for individuals with moderately severe stroke. Future high-quality, controlled studies should investigate the effects of balance training for individuals poststroke who have severe impairment, additional complications/comorbidities, or specific balance lesions (eg, cerebellar or vestibular). Optimal training dosage should also be further explored. Studies with long-term follow-up are needed to assess outcomes related to participation in the community and reduction of fall risk.

Sensory control of balance: a comparison of children with fetal alcohol spectrum disorders to children with typical development.

BACKGROUND: Inefficient central processing and integration of visual, vestibular, and somatosensory information may contribute to poor balance and diminished postural control in children with fetal alcohol spectrum disorders (FASD). OBJECTIVES: This pilot study examined sensorimotor performance and the sensory control of balance using a battery of clinical tests in combination with an experimental laboratory assessment that quantifies sensory subsystem use (i.e., sensory weighting) among a systematically diagnosed sample of children with FASD and children with typical development. METHODS: Using a case-control design, 10 children with FASD (8.0-15.9 years; 20% female) were compared to 10 age- and sex-matched controls on standardized clinical measures and on kinematic outcomes from the Multimodal Balance Entrainment Response system (MuMBER), a computerized laboratory assessment whereby visual, vestibular, and somatosensory input is manipulated at different frequencies during standing balance. RESULTS: Children with FASD showed poorer sensorimotor performance across clinical outcomes with significant group differences (p < .05) on parent-reported movement behaviors (Sensory Processing Measure and Movement Assessment Battery for Children-2 Checklist) and performance on the Dynamic Gait Index. Experimental kinematic outcomes yielded statistically significant group differences (p <.10) on a small proportion of somatosensory and vestibular sensory weighting fractions and postural sway velocity in response to the manipulation of sensory input. CONCLUSIONS: Preliminary findings showed small group differences in sensorimotor and sensory weighting behaviors, specifically those that rely on the integration of vestibular sensation. Differences must be examined and replicated with a larger sample of children with FASD to understand the impact on balance control and functional sensorimotor behaviors.