Using a Prism Paradigm to Identify Sensorimotor Impairment in Youth Following Concussion.

OBJECTIVE

The study assesses the intrarater reliability and utility of a prism paradigm to identify sensorimotor impairment following sports-related concussion in youth, (recent and history of concussion) compared with youth with no concussion.

SETTING

University of Calgary.

PARTICIPANTS

Three groups of 40 ice hockey players ranging in age from 11 to 17 years were included: (1) no concussion; (2) recent concussion, mean number of days since last concussion 5 (95% CI, 4-6); and (3) history of concussion, mean number of days since last concussion 631 (95% CI, 505-730).

DESIGN

Cross-sectional study.

MAIN MEASURES: The vestibulo-ocular reflex is a fundamental reflex of the central nervous system that stabilizes the position of the eyes during head movement and adapts when sensory input is altered (the bend of the light on the retina by prism glasses). The prism adaptation measure was the number of throws taken to adapt to wearing prism glasses while throwing balls at a central target.

RESULTS

The intraclass correlation coefficient (0.73; 95% CI, 0.55-0.84) and the Bland-Altman 95% levels of agreement (lower limit -18.5; 95% CI, -22.4 to -14.6); and upper limit 16.6; 95% CI, 12.7-20.5) reflected good intrarater reliability. Prism adaptation measures were significantly different across groups ( F2,119 = 51.9, P < .001, r = 0.52, power of 90%), with the mean number of throws for youth (aged 11-17 years) in each group as follows: 10 (95% CI, 8-12) no concussion history; 25 (95% CI, 23-27) recent concussion (1-11 days); and 17 (95% CI, 15-20) history of concussion (90-1560 days).

CONCLUSION

Use of a prism paradigm as a clinical measurement tool has the potential to alter concussion management in youth. The prism paradigm is objective, is readily translatable to the clinical arena, has minimal associated costs, and is easily administered, reliable, and portable.