Perturbation practice in multiple sclerosis: Assessing generalization from support surface translations to...

Area of Science:

• Neurology
• Rehabilitation Science
• Biomechanics

Background:

• Multiple sclerosis (MS) impacts balance and mobility in approximately 1 million individuals in the U.S.
• Impaired balance and mobility are significant challenges for people with multiple sclerosis (PwMS).
• Perturbation-based balance training may enhance protective stepping in PwMS, but generalization is not well understood.

Purpose of the Study:

• To investigate if protective stepping improvements from support surface translations generalize to a different balance task in people with multiple sclerosis (PwMS).
• To assess the transferability of motor learning from a specific balance training paradigm to novel reactive balance challenges.

Main Methods:

• Fourteen people with multiple sclerosis (PwMS) participated in two sessions, 24 hours apart.
• Balance tasks included tether-release and treadmill-based support surface translations to elicit backward protective stepping.
• Key outcome measures were margin of stability, step length, and step latency, analyzed using multilevel mediation models (MLMM).

Main Results:

• No significant mediated effects were found for margin of stability or step latency.
• Mediation was observed for step length, demonstrating increases during treadmill training that generalized to tether-release trials.
• Multilevel mediation models (MLMM) proved effective for analyzing generalization in motor training, even with small sample sizes.

Conclusions:

• Improvements in step length achieved through protective stepping training can generalize to different reactive balance tasks in people with multiple sclerosis (PwMS).
• This study highlights the potential of perturbation-based training to improve reactive balance in PwMS.
• Multilevel mediation models (MLMM) offer a valuable statistical approach for evaluating motor training generalization in clinical populations.