Longitudinal assessment of balance and gait after concussion and return to play in collegiate athletes

Context: In longitudinal studies tracking recovery after concussion, researchers often have not considered the timing of return to play (RTP) as a factor in their designs, which can limit the understanding of how RTP may affect the analysis and resulting conclusions. Objective: To evaluate the recovery of balance and gait in concussed athletes using a novel linear mixed-model design that allows an inflection point to account for changes in trend that may occur after RTP. Design: Cohort study. Setting: University athletics departments, applied field setting. Patients or Other Participants: Twenty-three concussed (5 women, 18 men; age ¼ 20.1 6 1.3 years) and 25 healthy control (6 women, 19 men; age ¼ 20.9 6 1.4 years) participants were studied. Participants were referred by their team athletic trainers. Main Outcome Measure(s): Measures consisted of the Balance Error Scoring System (BESS) total score, sway (instrumented root mean square of mediolateral sway), single-task gait speed, gait speed while simultaneously reading a handheld article (dual-task gait speed), dual-task cost of reading on gait speed, and dual-task cost of walking on reading. Results: We observed no significant effects or interactions for the BESS. Instrumented sway was worse in concussed participants, and a change in the recovery trend occurred after RTP. We observed group and time effects and group 3 time and group 3 RTP change interactions (P .046). No initial between-groups differences were found for single-task or dual-task gait. Both groups increased gait speed initially and then leveled off after the average RTP date. We noted time and RTP change effects and positive group 3 time interactions for both conditions (P .042) and a group 3 RTP change interaction for single-task gait speed (P ¼ .005). No significant effects or interactions were present for the dual-task cost of reading on gait speed or the dual-task cost of walking on reading. Conclusions: Changes in the rate of recovery were coincident with the timing of RTP. Although we cannot suggest these changes were a result of the athletes returning to play, these findings demonstrate the need for further research to evaluate the effects of RTP on concussion recovery.