Objective To examine tandem gait test (TGT) performance during single-task and dual-task conditions.

Design Prospective, longitudinal observational study

Setting Motion analysis laboratory

Participants Ten post-concussion (30% F, 19.0 [95% CI=15.6–22.4] years) and 7 control (57% F, 20.0 [16.7 -23.3] years) participants completed the TGT in single-task and dual-task conditions within 72 hours of sustaining a concussion and again at 1 week, 2 weeks, 1 month, and 2 months post-injury. Exclusion criteria included a current lower extremity injury, diagnosed learning disability, or documented prior concussion within the past year.

Independent variables TGT trials were performed without (single-task) and while concurrently performing a cognitive test (dual-task).

Outcome measures Participants completed 3 trials in each condition while whole body motion capture was performed. Outcome variables included the average completion time for the 3 trials, mean center-of-mass gait velocity, and cadence.

Main results Concussion participants took significantly longer to complete the dual-task TGT than controls (16.4 [13.4 -19.4] vs. 10.1 [6.4 -13.7] seconds) at the 72 hour, 1 week, and 2 week time points (p=.03); single-task TGT times were significantly lower 72 hours post-injury only (p=.04). Cadence was significantly lower for concussion participants across the two month testing period during dual-task TGT (89.5 [68.6 -110.4] vs. 127.0 [97.4 -156.6] steps/minute; p=.04). Mean gait velocity was lower for concussion participants at 72 hours post-injury in both conditions.

Conclusions Dual-task TGT deficits lasted longer for concussion participants than single-task TGT deficits. Including a secondary task during dynamic assessments of gait after concussion may increase the sensitivity to movement deficits that are undetectable using single-tasks.

Competing interests The authors have no conflicts of interest to report.