Reactive Balance Deficits Differ in People After Mild Traumatic Brain Injury Based on Chronicity of Self-Reported Symptoms.

BACKGROUND

Mild traumatic brain injury (mTBI) can lead to persistent balance impairments, affecting daily functioning. While mTBI deficits in static and dynamic balance are well-documented, reactive balance-essential for recovering from perturbations-remains understudied, and the relationship with symptom severity and quality of life remains unclear.

OBJECTIVE

Examine reactive balance across different stages of mTBI recovery and its association with self-reported symptoms and quality of life.

METHODS

This cross-sectional study included 82 participants: 19 with acute (4-14 days post-injury), 11 with sub-acute (3-12 weeks post-injury), 11 with chronic (>12 weeks post-injury) mTBI, and 41 healthy controls. Reactive balance was assessed using the Instrumented-modified Push and Release under both single and cognitive dual-task conditions, measuring time to stability and step latency.

RESULTS

Participants with acute mTBI had longer step latencies (P = .004 single-task; P = .016 dual-task) but no differences in time to stability compared to controls, while people with chronic mTBI exhibited longer time to stability (P = .004 single-task; P = .017 dual-task) but no difference in step latencies compared to controls. Dizziness and total symptom severity were moderately associated with single- and dual-task time to stability and dual-task step latency acutely, and with single-task time to stability and dual-task step latency in the sub-acute phase.

CONCLUSIONS

Reactive balance deficits persist chronically after mTBI and differ between people with acute, sub-acute, and chronic symptoms. These differences suggest people with chronic symptoms may prioritize different aspects of balance control compared to the people in the acute stage of recovery related to functional adaptations to self-reported symptoms.