Context: Managing a concussion injury should involve the incorporation of a multifaceted approach, including a vision assessment. The frontoparietal circuits and subcortical nuclei are susceptible to trauma from a concussion injury, leading to dysfunction of the vestibulo-ocular system. Research investigating the effect of cumulative subconcussive impacts on neurological function is still in its infancy, but repetitive head impacts may result in vestibular system dysfunction. This dysfunction could create visual deficits, predisposing the individual to further head trauma. Objective: The purpose of this study was to investigate the cumulative effect of subconcussive impacts on minimum perception time, static visual acuity, gaze stability, and dynamic visual acuity scores. Design: Prospective cohort. Setting: Division I university. Patients: Thirty-three Division I men’s lacrosse players (age = 19.52 [1.20] y). Intervention: Competitive lacrosse season. Main Outcome Measures: At the beginning and end of the season, the players completed a vestibulo-ocular reflex assessment, using the InVision™ system by Neurocom® to assess perception, static acuity, gaze stability, and dynamic visual acuity. Score differentials were correlated with the head impact exposure data collected via instrumented helmets. Results: A significant correlation was found between change in perception scores and total number of head impacts (r = .54), and between changes in dynamic visual acuity loss scores on the rightside and maximum rotational acceleration (r = .36). No statistical differences were found between preseason and postseason vestibulo-ocular reflex variables. Conclusions: Cumulative subconcussive impacts may negatively affect vestibulo-ocular reflex scores, resulting in decreased visual performance. This decrease in vestibulo-ocular function may place the athlete at risk of sustaining additional head impacts or other injuries.
Theresa L. Miyashita and Paul A. Ullucci
Sport-related concussions have recently been at the forefront of mainstream media, where the attention is now turning to the safety of our young athletes. With the recent rise of concussion lawsuits, coaches need to know concussion basics to protect their athletes and themselves. What we know about concussions has evolved, and it is critical that coaches understand these changes and how they impact the management of their teams’ injuries. In the absence of medical personnel, coaches are responsible for removing athletes from play if they have potentially sustained a concussion. Coaches must therefore understand the different mechanisms of injury, signs and symptoms, and the protocol to follow if they believe their athlete has sustained a concussion.