Gaze Stability Test Asymmetry Before and After Individualized Rehabilitation in Youth Athletes With Concussion.

Context: Concussion causes physiological disruptions, including disruptions to the vestibular and visual systems, which can cause dizziness, imbalance, and blurry vision. The vestibular ocular reflex functions to maintain a stable visual field, which can be measured using the gaze stability test (GST).

Design: This preliminary study used retrospective chart review to examine changes in GST performance and asymmetry in a sample of 117 youth athletes with concussion (mean age = 14.51, SD = 2.08) before (T1) and after (T2) they completed a vestibular therapy program that included in-office treatment by a vestibular physical therapist and a customized home exercise program. Examples of exercises that may be assigned in the home exercise program during vestibular therapy are provided.

Methods: After examining descriptive information, changes in GST scores and asymmetry percentage between time points were compared via Wilcoxon signed-rank tests. Results were also compared descriptively with previously published findings.

Results: Results revealed significant improvements in median GST in leftward and rightward direction head movements from T1 to T2 and a significant reduction in GST asymmetry (P < .001). Both GST in leftward and rightward direction head movements improved from 145.00 to 210.00°/s, which is above the 50th percentile in previously published literature with uninjured athletes. Asymmetry decreased from an average of 10.07% (SD = 7.89) to 4.11% (SD = 3.88), which is lower than in previously published literature.

Conclusions: Concussion produces symptoms that vary among individuals and between injuries. GST velocity and asymmetry values provide objective data about an athlete's impairment and progress in recovery within the vestibular domain. This can aid in making clinical decisions on return to play progression and promote a successful and safe return to sport.