Thread by @Scienceofsport

Rugby’s Return to Play protocols after concussion - yesterday, @WorldRugby announced some changes to the management of players after concussion. You can read it here: world.rugby/news/726094/wo… And here’s a thread on some of the process & science behind it, which I was involved in

@WorldRugby To begin with, let’s look at what happened in the past. First, there used to be a mandatory stand-down period - a concussion meant that player couldn’t play again for an agreed, pre-determined period (it was still open for case by case exceptions, though). Then that was replaced

@WorldRugby …by a GRTP (General Return To Play) protocol, where the concussed player went through six stages, and if they were symptom free at each, they were cleared to play. Any symptom caused a delay until they repeated that stage. The result of that, based on available data, is that

@WorldRugby …about a third of players who were concussed were able to play the next week (they went through the GRTP without a single delay), and two-thirds of players returned only after that week, thus missing at least one match. That has been the subject of some debate recently.

@WorldRugby About a year ago, World Rugby began a process of looking at the GRTP, and asking whether there’s a need and a way, both supported by evidence (very NB) to change it in such a way that it can be guided more conservatively IN CASES WHERE THIS IS NECESSARY & PRUDENT.

@WorldRugby So, the approach taken is consistent of what WR tries to do when making player welfare decisions, which is to gather evidence where it exists, and to consult with experts where needed. This slide explains the process. Things we know, things we don’t, things we’ll study in future

@WorldRugby On this issue, we have data from previous head injuries, and we have data from Injury Surveillance systems. That is all analyzed to try to understand what circumstances lead to longer recoveries after concussions, and which concussions resolve faster? That is, risk evaluation

@WorldRugby There are, however, things we don’t know. It’s a “messy” landscape, many moving parts across the whole world, and so where we have no data specifically on a point, we take the approach of asking experts. A group was formed with experts from around the world, from many sports

@WorldRugby The task, as shown in the green box, is to identify the circumstances & contexts that produce longer recoveries after concussion, so that we can formalize and propose guidance that changes the return to play, but, and this is key, without losing an individual management approach

@WorldRugby You might be wondering, why not simply mandate three weeks or 28 days of rest after concussion, as some have suggested? Well, a couple of things that hopefully help you realize that things are more complex than they may first appear. First, if you mandate 28 days, then every

@WorldRugby …single concussion would be treated the same, and every player with concussion would miss 4 matches. We know from our data that 20% of our concussions are picked up after matches, when players SELF-REPORT symptoms to their doctors. They trust the doctors and the system to treat

@WorldRugby …them. It is not unreasonable to have concerns that a mandate of 28 days off for a concussion would discourage such self-reporting, and it would also raise the threshold to diagnose a concussion. There is thus concern, and this comes from extensive consultation with players,

@WorldRugby …that mandating time off will create for the sport a different risk - rather than the risk of a player returning early after concussion, it might create a risk of never identifying a concussion in the first place, driving down their recognition. That would, arguably, be worse

@WorldRugby So, medical experts, among the best in the world, strongly support that just like for any injury, concussion must be managed on an individual basis, not with mandates. If a player recovers well, without complications, then earlier return should be possible. It benefits the system

@WorldRugby With that in mind, the question we then assessed is how to identify situations that require a more conservative approach because of likelier delayed recovery? To answer that, here is a schematic summarizing the head injury process. There is a past and present component to it.

@WorldRugby In the past, we have the concussion history of a player. We now know from data that previous concussion is a risk factor for longer return. So if a player has had previous concussion, then it is prudent that they delay return to play in a guided manner. This is shown by 1 below

@WorldRugby Next, number 2. This is the presentation of the injury at the time it happens. Some concussions are obvious, and we call these Criteria 1 cases (WR has a list of what they look like). Others are less obvious (Criteria 2, and others appear later). The expert recommendation is that

@WorldRugby …if a player is a Criteria 1 case, they should also follow a delayed and conservative return to play, as shown by 2 on the chart below.

@WorldRugby Finally, a player’s recovery in the 48 hours after injury is important. If a player is fully recovered & has no abnormal symptoms, cognitive or balance functions during the HIA3 test (48hrs post match), they are clear. If any abnormalities exist, their RTP is conservative (see 3)

@WorldRugby The end result is the following. Based on:
1) concussion history
2) Initial presentation
3) Recovery in 48 hrs after the match

A player is either delayed in RTP by 3 additional days, or is able to return within a week, but only if they have no concussion history & perfect tests

@WorldRugby Any time a player has a concussion history, they are also assessed by an Independent Concussion Consultant (ICC) before their return. Similarly, any time a player wants to return within a week (next game), they have an ICC consultation. The idea here is to put layers in place to

@WorldRugby …ensure no player is rushed back without being ready, but (and again, I stress this) without treating every injury with the same brush and forcing a potential situation where a player (and doctor) must choose between missing 4 matches and disclosing any symptoms. I’ve no doubt

@WorldRugby …that many will challenge that position and say the sport should just say 28 days, but it really isn’t that simple. Obviously, we need education of players and doctors to impress upon them how important disclosure is, to discourage the “hiding” of symptoms. But we also realize

@WorldRugby …that we function in a real world with humans whose incentives are complex and they will, sometimes, make these choices to play, and a 28 day standout puts them in a more difficult position. I for one (and this is the expert consensus) would rather we have honest players with

@WorldRugby …strong trust of their own doctors and the system, than a blanket and standard stand-down period. Another issue is that 28 days off compromises mental health and physical condition (even if non-contact training resumes within the 28 days). Point is, this is not as simple as some

@WorldRugby …people you’ll hear in the media and on the radio and TV are saying. Every decision creates 2nd and 3rd order consequences, and we have to be mindful of that. Anyway, back to this summary chart - what it means is that the only scenario where a player returns the very next match

@WorldRugby …is the one on the far right - a player has no concussion history, is not a Criteria 1 case at the time of injury, and they have a perfect/normal HIA3 assessment 48 hrs later. All others, for different reasons, would be placed on a conservative but still individually managed RTP

@WorldRugby We have some idea of the impact these changes will make. Currently about 35% of players return to play in the next match after their concussion. By introducing concussion history (1), initial presentation (2) and 48hr test result at HIA3 (3), this is expected to drop to 12% - 15%

@WorldRugby Those 12-15% (about 1 in 7) will be players without a history, whose initial injury appears mild, and who are completely resolved within 48 hours. Even then, they will be assessed by an independent consultation if they wish to play the next match.

@WorldRugby To wrap up, no system is perfect. No tool is 100% sensitive & specific. The sport is investing hugely in research studies improve the screening tests, so in future, this will certainly evolve again. It evolves in response to “pressure”, but it’s not pressure from people claiming

@WorldRugby …that changes should be made because they “feel so”. Rather, it’s pressure from experts & evidence, so as we move forward, we’ll study how these latest changes affect concussion diagnosis and management. It never ends, and nothing is ever perfectly known. Anyway, long thread!