Previous research and position statements have outlined the necessity of balance and gait testing in the post-concussion evaluation of athletes. However, many of the currently available balance testing techniques lack objectivity and sensitivity to the effects of concussion. Such balance impairments may exist following concussion due to disruption of vestibular and/or ocular motor systems. However, no clinically feasible tools have been longitudinally examined to detect gait balance control deficits or to investigate how vestibular or motor dysfunction may lead to gait imbalance. Additionally, participation in physical and cognitive activities post-concussion may affect recovery. While limited evidence exists to support this notion, further investigation is necessary to improve clinical management recommendations.

The proposed study will allow for the examination of tools which add value to post-concussion clinical evaluations and study-related outcomes will enhance the understanding of dynamic balance control and vestibular/ocular motor recovery, and their potential for implementation into concussion management protocols.

To address study hypotheses, the investigators plan to recruit subjects who have been diagnosed with a concussion by participating sports medicine physicians at the Boston Children's Hospital Sports Concussion Clinic. If patients elect to participate, they will undergo their regularly scheduled clinical examination along with two testing components requiring less than 15 minutes of additional time to complete: an instrumented gait balance assessment, a vestibular-ocular motor screen, and a weekly activity survey. Participants with concussion will be matched with control subjects who meet similar demographic characteristics and report to the clinic for other orthopedic injuries that do not affect brain function, gait, or either lower extremity.

During the assessment, participants will complete a protocol which measures balance control while walking and simultaneously completing a cognitive task, a vestibular-ocular motor ability, and physical and cognitive activity levels. As a need exists to develop protocols which utilize inexpensive, objective, and sensitive measurements to track concussion recovery, this study seeks to incorporate innovative and clinically feasible methods into the clinical examination of concussion.

Inclusion Criteria:

1. Age between 12 and 40 years
2. No history of concussion in the past year, and no lifetime history of more than 3 concussions
3. Diagnosed with concussion within the past 21 days (concussion group only)

Exclusion Criteria:

1. Lower extremity deficiency or injury, which may affect normal balance or gait
2. History of permanent memory loss
3. Diagnosis of Attention Deficit Disorder (ADD), Attention Deficit Hyperactivity Disorder (ADHD), learning disability, Down syndrome, or developmental delay

Patients will come from Boston Children's Hospital and The Micheli Center for Sports Injury Prevention. Concussion will be defined consistent with the latest best-practice consensus statement on concussion in sport as a brain injury defined as a complex pathophysiological process affecting the brain, induced by biomechanical forces. Informed consent will be obtained after study explanation and sufficient time to answer all study-related questions at each respective location.