Evaluating the contribution of reactive balance to prediction of fall rates cross-sectionally and longitudinally in persons with multiple sclerosis

Perturbation-based Balance Training to improve postural responses and falls in people with multiple sclerosis: a randomized controlled trial

PURPOSE

To determine the effects of Perturbation-based Balance Training (PBT) on postural responses and falls in people with multiple sclerosis (PwMS) and compare the results with conventional balance training (CBT).

MATERIALS AND METHODS

Thirty-four PwMS were randomized to receive 4 weeks of PBT or CBT. Latency of postural responses to external perturbations, Timed-Up-and-Go (TUG), 10-meter-walk (10MW), Berg Balance Scale (BBS), and Activities-specific Balance Confidence Scale (ABC) were measured at baseline and post-training. Also, the proportion of fallers and fall rate were assessed at a 3-month follow-up.

RESULTS

The latency of postural responses significantly decreased in PBT compared to CBT. TUG, 10MW, BBS, and ABC, at post-training, and relative risk of falls and fall rate at 3-month follow-up had no statistically significant between-group differences.

CONCLUSIONS

The results show that PBT is at least as effective as CBT in improving balance and decreasing falls, while it has superiority over CBT whenever the clinicians mainly aim to improve reactive balance strategies. Future studies with a larger sample size are warranted to complement the results of this study.Implication for rehabilitationPerturbation-based Balance Training is at least as effective as conventional balance training (CBT) in improving proactive postural control in people with multiple sclerosis (PwMS).Perturbation-based Balance Training has superiority over CBT in improving reactive postural control in PwMS.Perturbation-based Balance Training has no superiority over CBT in improving fall-related outcomes.

Using the Instrumented Sway System (ISway) to Identify and Compare Balance Domain Deficits in People With Multiple Sclerosis

OBJECTIVE

To develop a multiple sclerosis (MS)-specific model of balance and examine differences between (1) MS and neurotypical controls and (2) people with MS (PwMS) with (MS-F) and without a fall history (MS-NF).

DESIGN AND SETTING

A cross-sectional study was conducted at the Gait and Balance Laboratory at the University of Kansas Medical Center. Balance was measured from the instrumented sway system (ISway) assessment.

PARTICIPANTS

In total, 118 people with relapsing-remitting MS (MS-F=39; MS-NF=79) and 46 age-matched neurotypical controls.

INTERVENTION

Not applicable.

OUTCOME MEASURES

A total of 22 sway measures obtained from the ISway were entered into an exploratory factor analysis to identify underlying balance domains. The model-derived balance domains were compared between (1) PwMS and age-matched, neurotypical controls and (2) MS-F and MS-NF.

RESULTS

Three distinct balance domains were identified: (1) sway amplitude and velocity, (2) sway frequency and jerk mediolateral, and (3) sway frequency and jerk anteroposterior, explaining 81.66% of balance variance. PwMS exhibited worse performance (ie, greater amplitude and velocity of sway) in the sway velocity and amplitude domain compared to age-matched neurotypical controls (P=.003). MS-F also exhibited worse performance in the sway velocity and amplitude domain compared to MS-NF (P=.046). The anteroposterior and mediolateral sway frequency and jerk domains were not different between PwMS and neurotypical controls nor between MS-F and MS-NF.

CONCLUSIONS

This study identified a 3-factor, MS-specific balance model, demonstrating that PwMS, particularly those with a fall history, exhibit disproportionate impairments in sway amplitude and velocity. Identifying postural stability outcomes and domains that are altered in PwMS and clinically relevant (eg, related to falls) would help isolate potential treatment targets.

An Exploratory Study of Community Mobility in Adults With Multiple Sclerosis Across Different Ambulation Levels

BACKGROUND

The purpose of this study was to identify differences in community mobility in adults with multiple sclerosis (MS) at various ambulation levels.

METHODS

Seventy-one adults with MS completed a survey about their mobility impairment and avoidance of challenging mobility tasks. Individuals were categorized as having mild, moderate, or severe gait impairment.

RESULTS

Participants across the different functional groups significantly differed in perceived ambulation disability, fatigue impact, falls efficacy, quality of life, challenges with dual-tasking, and self-efficacy for community mobility. There were no significant differences between the mild and moderate gait impairment groups in crossing a busy street or going out in different ambient conditions. Significant differences were found between those with mild impairment and those with severe impairment in avoidance of various terrain elements, heavy manual doors, postural transitions, attentional situations, and crowded places. The only environmental dimension that significantly differed across all 3 groups was carrying 2 or more items, in which avoidance increased as ambulation worsened.

CONCLUSIONS

Avoidance behavior for particular environmental features can begin relatively early in the disease process. This underscores the need to further study mobility differences, community ambulation, and participation restrictions in adults with MS.

Examining the Relationship Between Reactive Stepping Outcomes and Falls in People With Multiple Sclerosis

OBJECTIVE

Reactive stepping is critical for preventing falls and is impaired in people with multiple sclerosis (PwMS); however, which aspects of stepping relate to falls remains poorly understood. Identifying outcomes most related to falls is a first step toward improving rehabilitation for fall prevention. The purpose of this study was to assess whether reactive step latency or length during forward and backward losses of balance were related to a history of falls in PwMS.

METHODS

Of the 111 PwMS who participated in this study, 76 reported no falls in the previous 6 months, whereas 36 reported 1 or more falls. Participants completed 3 forward and 3 backward treadmill-induced reactive steps from stance. Step length (centimeters) and step latency (milliseconds) were measured using motion capture and analyzed via MATLAB.

RESULTS

Participants with a history of falls had significantly slower step latencies during backward stepping, but not forward stepping, than those without a history of falls. Step length did not differ between groups. Slower step latencies during backward stepping significantly increased the odds of having experienced a fall (β = .908, SE = 0.403, odds ratio = 2.479, 95% CI = 1.125 to 5.464).

CONCLUSION

PwMS and a history of falling show delayed step onsets during backward reactive stepping. Specifically, for every 10-millisecond increase in step latency, PwMS were 2.5 times more likely to have a fall history. Although clinical trials are necessary to determine whether interventions targeting reactive stepping reduce falls in PwMS, the current work indicates that the latency of steps may be a relevant target for this work.

IMPACT

Subsequent fall prevention clinical trials should consider targeting backward reactive step latency to further assess its relevance for rehabilitation in PwMS.

LAY SUMMARY

If you have MS and a history of falls, you may be more likely to have delayed reactive step latencies.