Lower Limb Strength Differentiates Between Fallers and Nonfallers With Multiple Sclerosis.

OBJECTIVE

To determine whether hip flexion (HF), extension (HE), abduction (HA), knee flexion (KF) and extension (KE), and ankle plantarflexion (APF) and dorsiflexion maximum voluntary contraction (MVC) differentiates between nonfall and fall history in persons with multiple sclerosis (PwMS) after accounting for age, gender, fatigue, disability, and disease duration.

DESIGN

Secondary analysis of a cross-sectional study.

SETTING

Community-based comprehensive MS center.

PARTICIPANTS

A total of 172 PwMS who completed a 1-time visit.

INTERVENTIONS: Not applicable.

MAIN OUTCOME MEASURES: Lower limb (LL) MVC was measured for each muscle group as isometric peak torque (Newton-meter: Nm) of both limbs (Strongest: S; Weakest: W) using a Biodex Dynamometer and normalized by body weight (Nm/kg). Falls in the past 6 months were retrospectively collected and participants were classified as nonfall history (0 falls [nonfallers]; n=78) or fall history (≥1 falls [fallers]; n=94). Fall history was further categorized as occasional (1-2 falls [occasional fallers]; n=51) and recurrent (≥3 falls [recurrent fallers]; n=43).

RESULTS

Overall differences between participants with and without a fall history were noted on both limbs, with post-hoc analyses showing that those with a fall history had significantly lower strength (P<.05) on all LL-W and HF-S, HE-S, HA-S, KF-S, and APF-S. When separated out by fall frequency, recurrent fallers had diminished strength on all LL-W and HF-S, HE-S, HA-S, and APF-S, whereas occasional fallers exhibited reductions on HA-W, KE-W, and KF-W compared with nonfallers. Recurrent and occasional fallers differed on HE-W.

CONCLUSION

All LL-W and aspects of LL-S differentiated between fallers and nonfallers, with further differences observed when fall history was separated by frequency. These findings provide the necessary information to clinicians to inform their plans of care to address falls in MS and provide education on the importance of maintaining LL strength.