Investigation of Sensorimotor Impairments in Individuals 4 Weeks to 6 Months After Mild Traumatic Brain Injury

Abstract

Objective: To identify whether adults 4 weeks to 6 months post mild traumatic brain injury (mTBI) have sensorimotor impairments compared with controls without mTBI. A secondary aim was to determine if impairments were evident irrespective of participant perceived absence of symptoms. Design: Observational cohort study. Setting: Tertiary university and hospital. Participants: Participants included 113 individuals (N=113) aged 18-60 years, consisting of 39 controls with no prior concussion history and 74 individuals 4 weeks to 6 months post mTBI, of which 35 considered themselves asymptomatic (ASYMP) and 37 symptomatic (SYMP). Interventions: Not applicable. Main Outcome Measures: Assessments of oculomotor, vestibulo-ocular reflex (VOR) control, balance, single- and dual-task tandem walk, and vestibular positional testing. Results: Poorer balance and tandem walk performance as well as a higher frequency of positive oculomotor, VOR, and vestibular positional tests were evident in the mTBI group compared with controls. In particular ≥2 positive oculomotor findings were evident in 53.7% of the participants with mTBI compared with 10.8 % of controls. The mTBI group who considered themselves recovered (ASYMP) demonstrated significantly increased dual-task tandem walk time, and a higher proportion 53% had ≥2 positive oculomotor tests compared with controls. Conclusions: Persistent sensorimotor impairments, particularly evidenced by disturbed oculomotor function and deficits in dual-task tandem walking were identified among adults 4 weeks to 6 months post mTBI. These disturbances were evident regardless of whether ongoing symptoms were reported. The findings support recommendations for routine clinical assessment of sensorimotor function post mTBI with implications for injury prevention.