Toe grip force of the dominant foot is associated with fall risk in community-dwelling older adults: a cross-sectional study.

BACKGROUND: It is unclear whether the toe grip force (TGF) of the dominant foot (DF) and the lower limb function asymmetry (LLFA) in older adults are associated with fall risk. Therefore, this study aimed to investigate the effect of lower limb properties (such as TGF, muscle strength, and plantar sensation) on the risk of falls in older adults, while considering the foot dominance and asymmetry of lower limb function. METHODS: This study was a cross-sectional study. We determined whether the lower limb function of the DF and non-dominant foot (non-DF) and LLFA had any effect on the fall risk in 54 older adults (mean ± standard deviation: 72.2 ± 6.0, range: 60-87 years). We examined the participants' fall history, Mini-Mental State Examination (MMSE) score, lower limb function, and LLFA. To determine fall risk factors, we performed logistic regression analysis, with presence or absence of falls as the dependent variable. RESULTS: The independent variables were age, sex, MMSE score, two-point discrimination of the heel (non-DF) as plantar sensation index, and the TGF of both feet. Only the TGF of the DF was identified as a risk factor for falls (p < 0.05). CONCLUSIONS: In older adults, clinicians should focus on the TGF of the DF as a risk factor for falls. TRIAL REGISTRATION: This study was retrospectively registered. https://center6.umin.ac.jp/cgi-bin/ctr/ctr_up_rec_f1.cgi .

Eye Position Shifts Body Sway Under Foot Dominance Bias in the Absence of Visual Feedback.

Purpose: The purpose of this study was to investigate whether information on extraocular muscle proprioception without visual information affects postural control. Methods: Thirty-five healthy young volunteers participated in the study. Postural control outcomes included the center of pressure (CoP) for static standing, the total length of the sway of the CoP (LNG), and the sway area (SA), as well as the mean CoP in the mediolateral and anteroposterior directions. The following five eye-fixing positions were used: eye-up (E-Up), eye-down (E-Down), eye-right (E-Right), eye-left (E-Left), and eye-center (Center eye position). One-way ANOVA and Bonferroni correction was performed for statistical processing. Electrooculograms were recorded to detect eye orientation errors, measured with the eyes closed. Results: The results of this study showed no significant difference between the LNG and SA results when comparing respective eye positions (E-up, E-down, E-right, E-left) relative to E-Center (control). However, the average CoP was shifted to the right at E-Up, E-Down, and E-Left. Conclusion: These findings indicate that postural control may be affected by eye-body coordination depending on the position of the eyes, even without visual information.

Testing the Validity of the Diamond Steps Test for Balance in Healthy Adults.

OBJECTIVES: To test the validity of the Diamond Steps Test (DST), a new test to assess balance. DESIGN: This cross-sectional study evaluated the validity of the DST, a brief new balance assessment tool. SETTING: The implementation site was the rehabilitation center of a hospital. Data collection was conducted from February to June 2017. PARTICIPANTS: Healthy adults (N=65) between the ages of 40 and 72 years who volunteered to participate. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Two measures were used to assess DST: the time required to step around the diamond 5 times (5-DS) and the time required to step around the diamond twice, once using the dominant foot and the other using the non-dominant foot (LRDS). RESULTS: Multiple regression analysis was performed for each of the 2 methods for measuring DST. Five variables were predictive of DST as measured by the 5-DS test: the 10-Second Open Close Stepping Test, timed Up and Go (TUG) test, Y Balance Test (YBT) posterolateral reach for the left leg, Standing on One Leg with Eyes Closed (SOLEC) test for the right leg, and sex. The coefficient of determination was 0.54. For DST measured by the LRDS, 4 variables were found to be predictive: the 30-Second Chair Stand Test, YBT posterolateral reach for the left leg, TUG, and SOLEC for the right leg. The coefficient of determination was 0.49. CONCLUSION: The DST was shown to assess 7 of the 9 components of balance (static stability, functional stability limits, underlying motor systems, anticipatory posture control, dynamic stability, reactive postural control, and sensory integration), suggesting that it is a valid test to use for balance assessment.

Dominant vs. non-dominant hip comparison in bone mineral density in young sporting athletes.

To explore differences in bone mineral density (BMD) between dominant and non-dominant hip within levels of sport impact. BMD was higher in the non-dominant hip in high-impact sports, whereas the dominant hip had increased BMD for low-impact sports. The side-to-side differences were relatively small and not clinically relevant. PURPOSE: It is unknown whether there is difference in BMD at the hip between dominant and non-dominant sides in young athletes. The aims of this study were to explore the dominant-non-dominant differences in hip BMD in young athletes participating in low- and high-impact sports and to assess the effect of ground force impact on BMD. METHODS: Data was collected on University of Oxford athletes and controls (CG) between 2016 and 2018. Athletes were classified into two groups: high-impact sports (HIG) and low-impact sports (LIG). Total and regional measurements of both hips' BMD were recorded using a dual-energy X-ray absorptiometry (DXA). Linear regression method was used to assess differences in BMD between and within groups. RESULTS: One hundred ninety-four athletes (HIG: n = 89, LIG: n = 105) and 48 controls were included in this study. Total hip and femoral neck BMD was higher in athletes compared to the CG (p < 0.01), with HIG recording highest levels of BMD. The BMD difference between the dominant and non-dominant sides was significant in the LIG, with BMD being higher in the dominant side. Conversly, BMD was higher in the non-dominant hip within the HIG. However, the hip asymmetries were not clinically relevant (%BMD difference < 3%). A significant interaction between side and sport group on BMD was observed. CONCLUSIONS: High-impact sports had significantly higher BMD compared with low-impact sports and CG. BMD in the dominant hip was significantly higher for the LIG and lower in the HIG; however, differences were not clinically relevant.

Relationship between the mobility of medial longitudinal arch and postural control.

OBJECTIVE: The aim of this study was to analyze the relationship between the medial longitudinal arch mobility and static and dynamic balance. METHODS: A total of 50 subjects (25 female, and 25 male; Mean age: 22.2 ± 1.3 years; BMI: 22.8 ± 3.8 kg/m2) were included in this study. The relative arch deformity (RAD) was calculated with both 10% and 90% weight bearing (WB). Static balance was evaluated with Single Leg Stance Test and dynamic balance with TechnoBody PK 200WL computerized balance device. Subjects were evaluated for goniometric measurements of lower extremity joints, leg dominance and leg-length discrepancy. RESULTS: Bipedal dynamic balance was correlated with both feet length at 10% WB and 90% WB. There was a correlation between the dynamic balance on dominant foot and RAD value on the aspect of Medium Speed (r = -0.32, p = 0.02), Perimeter Length (r = -0.32, p = 0.02) and Anterior-Posterior Sway (r = 0.36, p = 0.01). Static balance was unaffected by RAD value when the visual system was eliminated. CONCLUSION: Our results suggest that decrease of arch mobility on the dominant foot is associated with posterior sway by causing knee or hip strategy and preventing ankle strategy even in small perturbations. The rate of deviation from the equilibrium point and the degree of total swaying increase when arch mobility decreases.