Use of a rapid visual screening tool for the assessment of concussion in amateur rugby league: A pilot study
Introduction
The identification and management of sports-related concussion is now an issue that is being faced by all sports. The risk of an acute catastrophic head injury [1] and long-term neurological sequelae as a result of repeated sports-related concussions [2] has been reported. The identification of concussion is a diagnostic challenge even for the sports medicine professional [3]. This is, in part, due to the fact that every sports-related concussion is unique and no two concussions present identically [3]. To complicate things further, the signs and symptoms of a sports-related concussion may not present immediately but may evolve over several hours to days after the event has occurred [3]. This challenge is even greater for the amateur sports volunteer who acts as the sideline medic or first aider.
Following the 2004 Second International Concussion In Sport (CIS) conference, the Sports Concussion Assessment Tool (SCAT) was published as part of the summary and agreement statement of those attending [4]. The third international conference on CIS in Zurich [5] resulted in the SCAT being amended and the SCAT2 was produced representing the only new sideline assessment tool published since 2009. The SCAT2 is a longer sideline concussion tool and, although is an improvement over the original SCAT, will require additional time of approximately 20 min to complete on the sideline making this more of a training room assessment tool as opposed to a readily available sideline assessment tool [3].
Originally developed as a reading tool to assess for the relationship between poor oculomotor functions and learning disabilities, the King–Devick (K-D) test uses a series of charts of numbers that progressively become more difficult to read in a flowing manner [6]. Poor oculomotor function has also been reported as one of the most robust discriminators for the identification of a mild Traumatic Brain Injury [7]. The K-D test has been reported to be a useful rapid screening test to assess sports participants with a suspected concussion on the sideline [8]. Requiring less than 2 min to administer, the K-D test is a practical sideline screening tool that is reportedly quicker than other concussion screening tools such as the Immediate Post-Concussion and Cognitive Testing (ImPACT), Cognitive Status Sport (Cog Sport) [9], the Standardized Assessment of Concussion (SAC) [10] and the Sports Concussion Assessment Tool 2 (SCAT2) [5]. Although these screening tools are useful in assessing for suspected concussion they do not assess eye movements or brain stem function well [11]. The K-D test does however test for impairment of eye movement, attention, language and other areas that correlate with sub-optimal brain function that may occur following a concussive episode [11]. The King–Devick [6], [8] is reportedly able to be completed on the sideline in less than a minute and has been moderately correlated (rs = − 0.54; p = 0.07) with the Military Acute Concussion Evaluation (MACE) [12]. With this in mind this study undertook to use the K-D sideline test with the SCAT2 to see if concussions could be identified in amateur rugby league players over a representative competition.
Section snippets
Methods
A prospective cohort study was conducted on two teams participating in the amateur representative rugby league regional competition season (seven teams from around New Zealand playing in a home and away competition format over eight weeks from August to October 2011). Over the duration of the study 50 players (mean (± SD) age; 22.4 ± 4.1 yr.; stature: 1.81 ± 0.06 m; mass: 96.0 ± 13.7 kg) were enrolled in the study. All players were considered amateur as they received no remuneration for participating in
Results
Over the duration of the study there were six round (12 games) resulting in 414.5 match exposure hours. Three concussions were identified by the team medic following witnessed events and two were found on routine post-match K-D testing, resulting in a concussion injury incidence of 12.1 (95% CI:1.5 to 22.6) per 1000 match hours. The K-D test was slightly correlated with the PCSS (rs = 0.206; p = 0.065) but this was not significant. The internal consistency reliability of the PCSS was excellent (α =
Discussion
The King–Devick (K-D) test is reported to be a strong candidate for rapid sideline screening test for concussion [8]. This study was conducted to assess the K-D test in an amateur rugby league environment for sideline screening for concussion. The findings of this study provides further evidence in support of previous studies [8], [18] reporting on the use of the K-D test as a sideline tool designed to complement other diagnostic sport-related concussion assessment tools. The K-D test was
Conclusion
The K-D test was able to identify players with a suspected concussion, players with a concussion that was not reported or witnessed, assist in monitoring concussed players return to play process and manage the return of a player with epilepsy. The ease-of-use of the K-D test made it more acceptable to team management and players and, as it provided immediate feedback to the player and coach the K-D test served to provide support for the decision made by the team medic to rule out the player
Conflict of interest
The authors declare that there are no competing interests associated with the research contained within this manuscript.
Funding
No source of funding was utilised in the conducting of this study.
Acknowledgements
We acknowledge Steve Devick for access to the King–Devick test platform for conducting of this study, and Laura Balcer and Steve Galetta for their guidance in the manuscript development.
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