Association Between Improved Mobility and Distal Health Outcomes.

BACKGROUND: We examined the association between improved mobility and distal health outcomes in older adults using secondary analysis of data from a cluster-randomized controlled group exercise trial. METHODS: Participants were 303 men and women aged ≥65 and older in 32 independent living facilities, senior apartments, and community centers who participated in 12-week group exercise interventions. Included were those who completed ≥1 follow-up phone call regarding outcomes assessment in the following year. Gait speed and 6-minute walk distance (6MWD) were assessed at baseline and immediately after 12-week interventions to determine mobility performance change status. Falls, emergency department (ED) visits, and hospitalizations were assessed monthly for 12 months following the end of interventions via interactive voice response phone calls. Incident rate ratios (IRRs) were calculated to quantify incidence of adverse outcomes with respect to mobility performance change. RESULTS: Each 0.05 m/s increase in gait speed resulted in an 11% reduction in falls (IRR = 0.89; 95% confidence interval [CI], 0.84-0.94; p < .0001); a similar decrease was seen for each 20 m increase in 6MWD (IRR = 0.89; 95% CI, 0.83-0.93; p = .0003). Those who improved gait speed had 61 falls per 1,000 person-months versus 135 in those who had no change/a decline. Those who improved 6MWD had 67 falls per 1,000 person-months versus 110 per 1,000 person-months in those who had no change/a decline. Differences in ED visits and hospitalizations were not statistically significant. CONCLUSION: Improvements in mobility performance are associated with lower incidence of future falls. Given the exploratory nature of the findings, further investigation is warranted.

The Effect of Auditory Cueing on the Spatial and Temporal Gait Coordination in Healthy Adults.

Walk ratio, defined as step length divided by cadence, indicates the coordination of gait. During free walking, deviation from the preferential walk ratio may reveal abnormalities of walking patterns. The purpose of this study was to examine the impact of rhythmic auditory cueing (metronome) on the neuromotor control of gait at different walking speeds. Forty adults (mean age 26.6 ± 6.0 years) participated in the study. Gait characteristics were collected using a computerized walkway. In the preferred walking speed, there was no significant difference in walk ratio between uncued (walk ratio = .0064 ± .0007 m/steps/min) and metronome-cued walking (walk ratio = .0064 ± .0007 m/steps/min; p = .791). A higher value of walk ratio at the slower speed was observed with metronome-cued (walk ratio = .0071 ± .0008 m/steps/min) compared to uncued walking (walk ratio = .0068 ± .0007 m/steps/min; p < .001). The walk ratio was less at faster speed with metronome-cued (walk ratio = .0060 ± .0009 m/steps/min) compared to uncued walking (walk ratio = .0062 ± .0009 m/steps/min; p = .005). In healthy adults, the metronome cues may become an attentional demanding task, and thereby disrupt the spatial and temporal integration of gait at nonpreferred speeds.

Motor learning versus standard walking exercise in older adults with subclinical gait dysfunction: a randomized clinical trial.

OBJECTIVES: To compare the effect of motor learning with that of standard exercise on measures of mobility and perceived function and disability. DESIGN: Single-blind randomized trial. SETTING: University research center. PARTICIPANTS: Older adults (n = 40) with a mean age of 77.1 ± 6.0, normal walking speed (≥ 1.0 m/s), and impaired motor skills (Figure of 8 walk time >8 seconds). INTERVENTIONS: The motor learning program incorporated goal-oriented stepping and walking to promote timing and coordination within the phases of the gait cycle. The standard program employed endurance training by treadmill walking. Both included strength training and were offered twice weekly for 1 hour for 12 weeks. MEASUREMENTS: Primary outcomes were mobility performance (gait efficiency, motor skill in walking, gait speed, walking endurance); secondary outcomes were perceived function and disability (Late-Life Function and Disability Instrument). RESULTS: Thirty-eight of 40 participants completed the trial (motor learning, n = 18; standard, n = 20). The motor learning group improved more than the standard group in gait speed (0.13 vs 0.05 m/s, P = .008) and motor skill (-2.2 vs -0.89 seconds, P < .001). Both groups improved in walking endurance (28.3 and 22.9 m, P = .14). Changes in gait efficiency and perceived function and disability were not different between the groups (P > .10). CONCLUSION: In older adults with subclinical gait dysfunction, motor learning exercise improved some parameters of mobility performance more than standard exercise.

White matter hyperintensities, exercise, and improvement in gait speed: does type of gait rehabilitation matter?

OBJECTIVES: To examine whether white matter hyperintensities (WMHs) on brain magnetic resonance imaging (MRI) in tracts in older adults with mobility impairment are linked to outcomes of gait rehabilitation interventions. DESIGN: Twelve-week randomized controlled single-blind trial. SETTING: University-based mobility research laboratory. PARTICIPANTS: Ambulatory adults aged 65 and older with mobility impairment. INTERVENTION: A conventional gait intervention focusing on walking, endurance, balance, and strength (WEBS, n = 21) and a task-oriented intervention focused on timing and coordination of gait (TC, n = 23). MEASUREMENTS: Self-paced gait speed was measured over an instrumented walkway before and after the intervention, and WMH and brain volumes were quantified on preintervention brain MRI using an automated segmentation process. A white matter tract atlas was overlaid on the segmented images to measure tract WMH volumes, and WMH volumes were normalized to total brain volume. Aggregate WMH volumes in all white matter tracts and individual WMH volumes in specific longitudinal tracts (superior longitudinal fasciculus, inferior longitudinal fasciculus, and fronto-occipital fasciculus) and the cingulum were measured. RESULTS: Gait speed gains in the TC group were of the same magnitude, independent of WMH volume measures in all except the cingulum, but in the WEBS group, gain in gait speed was smaller with greater overall tract WMH volumes (P < .001) and with greater WMH volume in the three longitudinal tracts (P < .001 to .02). CONCLUSION: Gains in gait speed with two types of gait rehabilitation are associated with individual differences in WMHs. Task-oriented therapy that targets timing and coordination of gait may particularly benefit older adults with WMHs in brain tracts that influence gait and cognition.

Evidence of validity for the Foot and Ankle Ability Measure (FAAM).

BACKGROUND: There is no universally accepted instrument that can be used to evaluate changes in self-reported physical function for individuals with leg, ankle, and foot musculoskeletal disorders. The objective of this study was to develop an instrument to meet this need: the Foot and Ankle Ability Measure (FAAM). Additionally, this study was designed to provide validity evidence for interpretation of FAAM scores. METHODS: Final item reduction was completed using item response theory with 1027 subjects. Validity evidence was provided by 164 subjects that were expected to change and 79 subjects that were expected to remain stable. These subjects were given the FAAM and SF-36 to complete on two occasions 4 weeks apart. RESULTS: The final version of the FAAM consists of the 21-item activities of daily living (ADL) and 8-item Sports subscales, which together produced information across the spectrum ability. Validity evidence was provided for test content, internal structure, score stability, and responsiveness. Test retest reliability was 0.89 and 0.87 for the ADL and Sports subscales, respectively. The minimal detectable change based on a 95% confidence interval was +/-5.7 and +/--12.3 points for the ADL and Sports subscales, respectively. Two-way repeated measures ANOVA and ROC analysis found both the ADL and Sports subscales were responsive to changes in status (p < 0.05). The minimal clinically important differences were 8 and 9 points for the ADL and Sports subscales, respectively. Guyatt responsive index and ROC analysis found the ADL subscale was more responsive than general measures of physical function while the Sports subscale was not. The ADL and Sport subscales demonstrated strong relationships with the SF-36 physical function subscale (r = 0.84, 0.78) and physical component summary score (r = 0.78, 0.80) and weak relationships with the SF-36 mental function subscale (r = 0.18, 0.11) and mental component summary score (r = 0.05, -0.02). CONCLUSIONS: The FAAM is a reliable, responsive, and valid measure of physical function for individuals with a broad range of musculoskeletal disorders of the lower leg, foot, and ankle.