Concussion Recovery Evaluation Using the Inertial Sensor Instrumented Y Balance Test

The current sports concussion assessment paradigm lacks reliability, has learning effects, and is not sufficiently challenging for athletes. As a result, subtle deficits in sensorimotor function may be unidentified, increasing the risk of future injury. This study examined if the inertial-sensor instrumented Y Balance test could capture concussion-induced alterations in dynamic movement control. A cohort of 226 elite Rugby Union, American football, and ice hockey athletes were evaluated using the inertial-sensor instrumented Y balance test. Dynamic balance performance was quantified using normalized reach distance, jerk magnitude root-mean-squared (Jerk Mag RMS), and gyroscope magnitude sample entropy (Gyro Mag SEn). Concussed athletes who consented to follow-up were evaluated 24 to 48 h post-injury, and at the point of return to full contact training (RTP). Seventeen athletes sustained a concussion and consented to both the 24- to 48-h and RTP follow-up testing. Twenty uninjured control athletes were re-tested 6 months following initial screening. Concussed athletes had reductions in normalized reach distance (Cohens D = 0.66-1.16) and Jerk Mag (Cohens D = 0.57-1.14) 24 to 48 h post-injury, which returned to pre-injury levels by the point of RTP. There was no significant difference in performance between the baseline and 6-month follow-up in the 20 uninjured athletes (Cohens D = 0.06-0.51). There was a statistically significant linear association between Jerk Mag RMS 24 to 48 h post-injury and the natural log of RTP duration (R = 0.27 to 0.33). These results indicate that concussed athletes possessed alterations in dynamic movement control 24 to 48 h post-concussion, which typically returns to pre-injury levels by the point of RTP. Further, evaluation of dynamic movement control 24 to 48 h post-injury may aid in the evaluation of recovery prognosis.