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Background Reactive balance recovery evokes a negative peak of cortical electroencephalography (EEG) activity (N1) that is simultaneous to brainstem-mediated automatic balance-correcting muscle activity. This study follows up on an observation from a previous study, in which N1 responses were larger in individuals who seemed to have greater difficulty responding to support-surface perturbations. Research Question We hypothesized that people engage more cortical activity when balance recovery is more challenging. We predicted that people with lower balance ability would exhibit larger cortical N1 responses during balance perturbations. Methods In 20 healthy young adults (11 female, ages 19–38) we measured the amplitude of the cortical N1 response evoked by 48 backward translational support-surface perturbations of unpredictable timing and amplitude. Perturbations included a Small (8 cm) perturbation that was identical across participants, as well as Medium (13−15 cm) and Large (18−22 cm) perturbations scaled to participant height to control for height-related differences in perturbation difficulty. To assess individual differences in balance ability, we measured the distance traversed on a narrow (0.5-inch wide) 12-foot beam across 6 trials. We tested whether the cortical N1 response amplitude was correlated to balance ability across participants. Results Cortical N1 amplitudes in response to standing balance perturbations (54 ± 18 μV) were inversely correlated to the distance traveled in the difficult beam-walking task (R2 = 0.20, p = 0.029). Further, there was a significant interaction between performance on the beam-walking task and the effect of perturbation magnitude on the cortical N1 response amplitude, whereby individuals who performed worse on the beam-walking task had greater increases in N1 amplitudes with increases in perturbation magnitude. Significance Cortical N1 response amplitudes may reflect greater cortical involvement in balance recovery when challenged. This increased cortical involvement may reflect cognitive processes such as greater perceived threat or attention to balance, which have the potential to influence subsequent motor control.

Research Objectives To examine sensorimotor control of walking with various haptic input modalities in people with multiple sclerosis (pwMS). Design Cross-sectional observational study. Setting Research gait laboratory. Participants Ethics approval and informed consent were obtained prior to data collection. Participants included 30 pwMS and 29 controls matched for age (±3 years) and sex. All participants were ≥ 18 years of age, and able to walk 10 m without support. Participants with conditions or injuries other than MS that could impair walking were excluded. Interventions Not applicable. Main Outcome Measures Walking without haptic input (no-touch: NT) was compared to three walking conditions with haptic input: haptic anchors (small weights on strings: HA), using a four-wheeled walker (4WW) with light touch (4WW-LT) and using a 4WW by placing weight through the handles (4WW-W). Inertial sensors (Mobility Lab, APDM) measured stride length1, gait speed2, percentage double support/stride (%DS)3, mediolateral trunk range of motion (ML-tROM)4, and lateral step variability (LSV)5. Repeated measures ANOVA examined within-and between-group differences. Results Group effects showed PwMS spent significantly greater time in %DS and had more LSV compared to controls. All participants spent less time in %DS in the 4WW-W condition compared to the other forms of haptic input. Both 4WW conditions and the haptic anchors reduced ML-tROM compared to NT. LSV was reduced with 4WW-LT and 4WW-W compared to HA and NT conditions. All participants walked significantly faster using 4WW-LT compared to all conditions. Conclusions PwMS walked with more caution and less consistent foot placement than controls. Adding only haptic input (anchors and 4WW-LT conditions) reduced ML-tROM similar to the 4WW-W condition (haptic input + mechanical support). 4WW-LT and 4WW-W demonstrated the added benefit of reducing LSV suggesting sensory information from a 4WW may improve walking balance control in pwMS; however, the reduced LSV may be due to the presence of the 4WW frame. PwMS could be encouraged to use a 4WW in different ways to support walking balance. Author(s) Disclosures Authors declare no conflict of interest.

Background Altered standing balance during pregnancy has been previously reported. To date, body center of mass (bCOM) motion has not been used to track balance changes in this population. We recently compared three methods to determine the torso center of mass (tCOM) location (via force plate acquired center of pressure calculation, using Pavol surface anthropometry measurements, and a combination of the two) to use in calculating the bCOM during pregnancy. Research question This current research explored two questions: (1) does walking balance change during pregnancy, and (2) do the methods for identifying tCOM location affect the resulting balance measures? Methods Fifteen pregnant women were recruited to perform 60-second trial of treadmill walking at 4-week intervals from 12 weeks gestation until delivery. Walking balance was measured as bCOM motion within the base of support. Gestation time and anthropometric model (force plate, Pavol, and combination) were repeated-measures independent variables in a general linear mixed model analysis. Results There was a significant decrease in walking balance during pregnancy. As gestation progressed, we observed non-linear changes in the bCOM motion within the base of support over time, with some changes starting early in pregnancy and others not starting until late 2nd trimester. The anthropometric model used to locate the bCOM significantly influences balance measures. The results of this study indicate that the force plate method is more appropriate for locating the tCOM in the anterior and lateral directions. Significance The results of this study will inform clinicians and patients about the gestational stage-associated changes in balance during pregnancy that increase the risk of falling and injury. Researchers should also carefully consider the method for locating the bCOM.

People with chronic stroke (PwCS) are susceptible to mediolateral losses of balance while walking, possibly due in part to inaccurate control of mediolateral paretic foot placement. We hypothesized that mediolateral foot placement errors when stepping to stationary or shifting visual targets would be larger for paretic steps than for steps taken by neurologically-intact individuals, hereby referred to as controls. Secondarily, we hypothesized that paretic foot placement errors would be correlated with previously identified deficits in isolated paretic hip abduction accuracy. 34 PwCS and 12 controls walked overground on an instrumented mat used to quantify foot placement location relative to parallel lines separated by various widths (10, 20, 30 cm). With stationary step width targets, foot placement errors were larger for paretic steps than for either non-paretic or control steps, most notably for the narrowest prescribed step width (mean absolute errors of 3.9, 2.3, and 1.9 cm, respectively). However, no differences in foot placement accuracy were observed immediately following visual target shifts, as all groups required multiple steps to achieve the new prescribed step width. Paretic hip abduction accuracy was moderately correlated with mediolateral foot placement accuracy when stepping to stationary targets (r = 0.49), but not shifting targets (r = 0.16). The present results suggest that a reduced ability to accurately abduct the paretic leg contributes to inaccurate paretic foot placement. However, the need to ensure mediolateral walking balance through mechanically-appropriate foot placement may often override the prescribed goal of stepping to visual targets, a concern of particular importance for narrow steps.

Rapid motor learning may occur in situations where individuals perceive a threat if they do not perform a task well. This rapid motor learning may be facilitated by improved motor performance and, consequently, more errorless practice. As a first step towards understanding the role of perceived threat on rapid motor learning, the purpose of this study was to determine how performance of a motor task is affected in situations where perceived threat is high. We hypothesized that perceived threat in a virtual environment would result in improved performance of a walking task (i.e., walking on a narrow beam). Results demonstrated that increased perceived threat did not yield statistically significantly greater balance performance in the high-threat virtual environment (median percentage of successful steps: 78.8%, 48.3%, and 55.2% in the real low-threat, virtual low-threat, and virtual high-threat environments, respectively). These results may be partially attributed to habituation to threat over time and practice. If implemented carefully, virtual reality technology can be an effective tool for investigating walking balance in environments that are perceived as threatening.

Spinal cord injury affects walking balance control, which necessitates methods to quantify balance ability. The purposes of this study were to 1) examine walking balance through foot placement variability post-injury; 2) assess the relationship between measures of variability and clinical balance assessments; and 3) determine if spatial parameter variability might be used as a clinical correlate for more complex balance measurements.Ten persons with spinal cord injury walked without devices on a split-belt treadmill at self-selected speeds. Ten healthy controls walked at 0.3 and 0.6m/s for comparison. Variability of step width and length, anteroposterior and mediolateral foot placements relative to center-of-mass, and margin-of-stability were calculated. Clinical assessments included Berg Balance Scale and Dynamic Gait Index.Participants with spinal cord injury demonstrated significantly different variability in all biomechanical measures compared to controls (P ≤ 0.007). Berg Balance Scale scores were significantly inversely associated with step length as well as anteroposterior and mediolateral foot placement variability (P ≤ 0.05). Dynamic Gait Index scores were significantly inversely associated with mediolateral foot placement variability (P ≤ 0.05). Participants with spinal cord injury showed significant correlations between spatial parameter variability and all other measures (P ≤ 0.005), except between step length and margin-of-stability (P=0.068); controls revealed fewer correlations.Persons post-spinal cord injury exhibit an abnormal amount of stepping variability when challenged to walk without devices, yet preserve the ability to avoid falling. When complex laboratory measures of variability are unavailable clinically, spatial parameter variability or standardized balance assessments may be plausible indicators of walking balance control.

The orthopedics at the rehabilitation hospital found that disorders caused by sports injuries to the feet or caused by lower-back are improved by wearing dynamic shoe insoles, these improve walking balance and stability. However, the relationship of the lower-back and knees and the rate of increase in stability were not quantitatively analyzed. In this study, using two accelerometers, we quantitatively analyzed the reciprocal spatiotemporal contributions between the lower-back and knee of patients with left lower-back pain by means of Relative Power Contribution Analysis. When the insoles were worn, the contribution of the left and right knee relative to the left lower-back pain was up to 26% (p lt 0.05) greater than without the insoles. Comparing patients with and without insoles, we found that the variance in the step response analysis of the left and right knee decreased by up to 67% (p lt 0.05). This shows an increase in stability. Language: en

Every year there are thousands of pedestrians in Sweden who are injured because of slippery pavements and roadways. Using an appropriate anti-skid device may reduce the risk of slips and falls on ice and snow. Methods to describe functional problems in walking on different slippery surfaces during winter have been developed as rating scales for evaluating walking safety and walking balance and an observation method to observe posture and movements during walking. Practical tests of all 25 anti-skid devices on the market in Sweden were carried out on different slippery surfaces; gravel, sand, salt, snow and ice. The anti-skid devices were described according to the subjects' perception of walking safety, walking balance and priority for own use. The postures and movements during walking were analysed by an expert physical therapist. The wholefoot device 'studs' was perceived as the best according to walking safety and walking balance and had the highest priority for own use.

Summary The effect of cervical collars on walking balance was examined in two age groups. Twenty healthy women aged 60 to 78 years and 20 aged 18 to 29 years walked on a computerised walkway with and without a cervical collar. Variability of stride width and double support time was meaured. Analysis of variance showed no significant difference (p ) between the collar and no collar conditions In any of the subjects, for either of the walking balance measures. Older women had significantly increased (p

significant positive correlation with FTSTS times (r= 0.445 to 0.576, p< 0.006). Conclusion(s): The PWT showed good to excellent intrarater, inter-rater and test-retest reliability in people with chronic stroke. The PWT times significantly correlated with motor control and functional balance strength of lower limbs, and walking speed in people with chronic stroke. Implications: The PWT is an easy-to-administer and reliable clinical test in assessing walking balance in people with chronic stroke.