Characterizing reactive balance after mild traumatic brain injury

PROJECT SUMMARY / ABSTRACT Persistent balance problems are common sequelae after mild traumatic brain injury [mTBI]. Current approaches to treat these balance problems traditionally focus on principles of sensory integration derived from vestibular rehabilitation. However, recent evidence using destabilizing perturbations suggests that balance deficits may originate from motor impairments, rather than sensory impairments. This reactive balance – the ability to recover stability after an external perturbation – is an important domain of balance that is distinct from static (i.e., standing) and dynamic (i.e., walking) balance tasks. Preliminary studies suggest this reactive balance is impaired after mTBI, but the components underlying these impairments and the extent to which these impairments manifest during daily life remain unclear. While reactive balance can be improved through perturbation-based balance training in other populations, current clinical practice guidelines for the treatment and management of mTBI provide no guidance on treating reactive balance. The objective of this study is to understand the components underlying reactive balance deficits in people with mTBI and their impact on daily life. The long-term goal is to guide targeted rehabilitation approaches that incorporate rapid motor responses and reactive balance training to improve the function and quality of life for people with imbalance after mTBI. Using a sliding platform and mechanized shoes, we will examine how mTBI affects reactive balance during standing and locomotion, including walking and turning. Specifically, we will examine the two important components of reactive balance: the ability to prepare (i.e., prime) a motor response in anticipation of an upcoming perturbation and the ability to execute a motor response after a loss of balance. We will also develop a method to assess reactive balance during daily life using wearable inertial sensors to assess reactive balance during free-living daily mobility. Our aims will provide component-specific (Aim 1) and task-specific (Aim 2) targets for future rehabilitation while exploring reactive balance during daily living (Aim 3). Combined, these aims will provide the foundation for new, perturbation-based balance rehabilitation after mTBI, including innovative methods to assess reactive balance during daily living, that can complement current standard-of- care.