Fifty shades of grey: concussion complexities and constructive conclusions.

QUESTIONS BEING ASKED Quarrie and Murphy question the relevance of current concussion consensus definitions, particularly as they translate to the real world. The authors make pragmatic recommendations. Specifically, they suggest that the increasing incidence of concussion may be partly due to the expanded ‘theoretical’ definition, and that changes in the manner in which the SCAT3 is implemented and interpreted may more accurately diagnose the condition. Similarly, a number of recent articles have highlighted the fact that the ‘theoretical definition’ of concussion, as outlined in the current Zurich statement, lacks sensitivity and specificity. Furthermore, basic concepts of concussion management, such as a period of absolute rest and graded return to play, lack a strong evidence base. 3 Increasingly, concussion in sport appears to have become ‘a grey area about grey matter’, with an increasingly wide net cast to capture more cases, the management of which remains subject to varied opinion and some conjecture.