Predicting Post-Stroke Gait and Balance Function with Simple Neuromotor Measures
Background:
Stroke commonly results in permanent damage to central neural circuits. At a physiological level, this damage manifests as neuromotor impairments like reduced muscle strength, altered coordination, and delayed reaction time. At a functional level, this damage results in reduced gait speed, endurance, and balance ability, which leads to long-term disability and loss of independence. However, the interplay between these neuromotor impairments and functional disability is not well understood. An understanding of these relationships is critical to tailoring rehabilitation approaches for post-stroke recovery.
Methods:
We measured upper extremity neuromotor capacities as well as mobility and balance measures in 20 chronic stroke survivors and 20 age- and sex-matched controls for this cross-sectional, case-control study. The upper extremity neuromotor capacities included grip strength and various reaction time measures (simple reaction time [SRT], reaction accuracy [All Accuracy], and All Accuracy/SRT) derived using the ReacStick-a novel instrumented ruler-drop test that provides greater ecological validity than computer-based measures. The mobility and balance measures included preferred gait speed, 6-minute walking distance, timed up-and-go test, and single leg balance ability. ANOVAs were used to make between-limb and between-group comparisons, and linear and logistic regression analyses were used to evaluate the neuromotor capacities as predictors of mobility and balance.
Results:
All neuromotor capacities except All Accuracy and all mobility and balance measures were negatively affected by stroke (all p <0.02). We observed that grip strength symmetry (the ratio of grip strength in the paretic limb to the nonparetic limb) was the primary predictor of all mobility measures (all p ≤0.014), and SRT symmetry and paretic All Accuracy/SRT were the primary predictors of balance (all p ≤0.002).
Conclusions:
These results serve as foundational evidence for the relationship between neuromotor performance and functional ability following a stroke and may present an accessible clinical tool for safe measurement of post-stroke mobility and balance.
