Modest utility of brief oculomotor test for concussion screening in military mixed-martial arts training

ABSTRACT

Primary Objective: To assess a rapid concussion screening tool in Service members participating in combatives (mixed martial arts; MMA) training school.

Research Design: This prospective study included baseline and either post-training or post-injury assessments.

Methods and Procedures: Baseline (N = 152) and post-assessments (n = 129) of Service members included symptom reporting and the King-Devick (KD) oculomotor test.

Outcomes and Results: Headache, balance problems, and dizziness were the most severe concussive symptoms. KD scores for those who sustained a concussion (n = 31) were significantly worse compared to baseline, but not for participants who finished the course with no concussion (n = 98). For concussed, 74.2% had scores that were worse from baseline (slower) compared to 39.8% of the post-training group. KD scores were worse 34.4% more in individuals who sustained a concussion compared to those who did not. However, there was poor discriminant ability of the KD test (AUC = .60, sensitivity/specificity) to distinguish between concussed and non-concussed participants.

Conclusions: The KD test should not be used in isolation as a sideline or field concussion assessment during training scenarios. Rather, it has potential utility for evaluating individual cases to supplement decision making when an established baseline is available.

KEYWORDS:

• Concussion
• mild traumatic brain injury
• oculomotor
• King-Devick
• MMA

Acknowledgments

The authors would like to acknowledge Dr. Michael Russell and Dr. Harvey Watson for their contribution during the inception of the study including attaining initial funding and the development of the protocol, and Dr. Todd Christensen for his role in attaining command approvals. Also, a special thanks to Shelley Callahan for assisting with data collection.

Declaration of Interest

The authors reported no financial support and/or statements of potential conflict of interest.

Additional information

Funding

This work was supported by the Us Army Medical Research and Materiel Command.