Gait and Quiet-Stance Performance Among Adolescents After Concussion-Symptom Resolution

Context: Concussions affect a large number of US athletes each year. Returning an athlete to activity once self-reported symptoms have resolved can be problematic if unrecognized neurocognitive and balance deficits persist. Pairing cognitive and motor tasks or cognitive and quiet-stance tasks may allow clinicians to detect and monitor these changes postconcussion. Objective: To prospectively examine adolescent athletes' gait and quiet-stance performance while concurrently completing a cognitive task acutely after concussion and after symptom resolution. Design: Case-control study. Setting: Sport concussion clinic. Patients or Other Participants: Thirty-seven athletes (age = 16.2 +/- 3.1 years; 54% female) were diagnosed with a concussion, and their performance was compared with that of a group of 44 uninjured control participants (age = 15.0 +/- 2.0 years; 57% female). Intervention: Participants diagnosed with a concussion completed a symptom inventory and single-and dual-task gait and quiet-stance evaluations within 21 days of injury and then again after symptom resolution. Gait and postural-control measurements were quantified using an inertial sensor system and analyzed using multivariate analyses of covariance. Main Outcome Measure(s): Post-Concussion Symptom Scale, single-task and dual-task gait measures, quiet-stance measures, and cognitive task performance. Results: At the initial postinjury examination, single-task gait stride length (1.16 +/- 0.14 versus 1.25 +/- 0.13 m, P = .003) and dual-task gait stride length (1.02 +/- 0.13 m versus 1.10 +/- 0.13 m, P = .011) for the concussion group compared with the control group, respectively, were shorter. After symptom resolution, no single-task gait differences were found, but the concussion group demonstrated slower gait velocity (0.78 +/- 0.15 m/s versus 0.92 +/- 0.14 m/ s, P = .005), lower cadence (92.5 +/- 12.2 steps/min versus 99.3 +/- 7.8 steps/min, P= .001), and a shorter stride length (0.99 +/- 0.15 m versus 1.10 +/- 0.13 m, P = .003) during dual-task gait than the control group. No between-groups differences were detected during quiet stance at either time point. Conclusions: Acutely after concussion, single-task and dual-task stride-length alterations were present among youth athletes compared with a control group. Although single-task gait alterations were not detected after symptom resolution, dual-task gait differences persisted, suggesting that dual-task gait alterations may persist longer after concussion than single-task gait or objective quiet-stance alterations. Dual-task gait assessments may, therefore, be a useful component in monitoring concussion recovery after symptom resolution.