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Saturday, July 09, 2011

The Tour takes on a new complexion

A new complexion for the Tour and a serious day of crashes

Today the Tour rolls into its first 'taste' of mountains, with a finish up to Super-Besse Sancy that will almost certainly see a change in the yellow jersey.  Thor Hushovd has commanded yellow for since the team-time trial, but his slim lead over a host of riders is likely to be erased over a stage that includes a Category 2 climb and a fairly tough pull up to the finish in Super Besse Sancy.

Hushovd has done himself proud in the first week, defending that one second lead on a fairly tough, but short climb to Mur-de-Bretagne, although we knew that he climbs well for a big powerful man.  However, the much longer Category 2 climb, and the eight to nine percent grades may prove too much, and this is where the smaller riders come through - climbing is all about power to weight ratio, for the newer followers of the sport.  And so these are the climbs where the ability to sustain 6 W/kg for upward of 30 minutes start to tell, as I introduced in our video post earlier this week. The stage profile is below, courtesy cyclingnews.com.

Tomorrow is another tough, interesting "roller-coaster" with three Category 2 climbs and three Cat-3 climbs, before a rest day, then a few days of "calm before the storm" when the race reaches the high mountains of the Pyrenees and Luz Ardiden on Bastille day, Thursday 14 July.

A dramatic day - Horner's startling symptoms a rare view into head injury

Yesterday, however, was a dramatic day for all the wrong reasons.  A relatively uneventful stage suddenly turned, in this case for the worse, at about 38km to go, when a crash took down two pre-race contenders, Brad Wiggins and Chris Horner, and caused big delays for a number of other notable riders, including Levi Leipheimer.

It was Horner's story that unfolded as the most dramatic, because he actually continued to ride, receiving some medical attention on the bike, but ultimately lost over 12 minutes to the peloton.  However, it was the story after the finish line that was most disturbing.  Below is a video, courtesy Bicycling.com, that shows Horner crossing the finish line where he is met by a Radioshack team helper.  That is followed by an interview with Team Director Johan Bruyneel and then more footage of Horner as he is taken into an ambulance.

It's disturbing because it captures the immediate effects of a head injury.  You will hear Horner repeatedly asking people whether he finished the stage, and when the crash happened.  "I don't understand...when did I crash though?  Has it been a long time?"  Later he asks "Did I finish with the group or no?  But I finished?" He is completely out of touch with what happened and it's really eye-opening, startling and disturbing footage.

A decision will be made this morning as to whether Horner can continue, but I doubt that he will, and in fact that he should (late addition - Horner has been confirmed as abandoning and will not start the stage today, but is doing better, his second scan clear).  Yesterday also saw the abandonment of Tom Boonen, who also sustained a head injury in a crash two days before.  Then there is the case of Mauricio Soler, the Colombian rider who was involved in a very serious crash during the Tour of Switzerland a few weeks ago, and he is recovering but showing signs of "serious cognitive deficits".

The dangers of head injury and the need for a standard policy

It's a stark reminder of one of the dangers of cycling that we rarely think about.  Traumatic brain injury is a big issue in contact sports, like American Football, where the long-term effects of repeated head injuries have been the subject of probes and debates at the highest levels in Congress.  Malcolm Gladwell once compared it to dog-fighting, so inherent in the sport was head injury and so severe the prognosis of players involved in repeated collisions.

Also, in rugby, our big sport down here in South Africa, the diagnosis and management of head injuries and concussion are a serious business.  I have a colleague who has been conducting research into rugby injuries at two junior national tournaments in the last few weeks, and he was telling me just the other day that they were seeing a relatively high number of concussions.  And with the same dramatic symptoms that you saw above - players who don't know their names for minutes after the injury, for example.  Most recently, during my trip to Edinburgh with the SA Sevens team, we lost a player in that epic final to a concussion, and it's alarming to spend time with an athlete immediately after that.  Spending even five minutes seeing the effects is a wake-up call to anyone to be informed and aware of the dangers of traumatic brain injury.

In cycling, the issue seems to need some kind of policy - this article interviews Dr Prentice Steffen on who makes the decision for a rider to continue when they have suffered a head injury.  In the case of Boonen, he rode on after injury, plus did one more stage, before abandoning.

The complexity of concussion

The diagnosis and management of concussion is extremely challenging.  For example, this article from Neurology earlier this year used a test called the King-Devick test as a means to diagnose concussion in boxers and MMA fighters, the goal being to validate a rapid sideline tool that could accurately pick up any neurological problems.  The researchers compared it to a more comprehensive test, the Military Acute Concussion Evaluation, and concluded that their King-Devick sideline test was an accurate and reliable tool of concussion.

This was followed by letter from two researchers who have published a great deal in the field, warning against the "lure of simplicity".  Their main points (the article is available through University libraries) are that there is still no "diagnostic gold standard" for concussion, so we don't really now how to measure one test against another.  It's not as though there is a globally accepted best way to diagnose concussion, and so any new test is kind of being compared against a moving target.

Also, the study didn't actually test diagnosed concussion, but only looked at cognitive performance before and after a fight.  Given that fatigue could also affect the result, and that their athletes were boxers or MMA fighters, how relevant is this kind of test to football, to rugby, or maybe to cycling, where a once-off trauma occurs?  And finally, effective diagnosis of concussion requires that there is some baseline test BEFORE concussion, so that you know what you're comparing test results to.  The ultimate conclusion was that any test, however promising, needs a whole lot of research to establish just how relevant it is for a given context or situation.

Now, I'm not about to make a call on who is correct, or whether the test is oversimplified.  That is a neurology debate for those with a lifetime of specific research in the field.  However, I use that debate to highlight a) that there are a number of different approaches to diagnosis of concussion;  b) that "quick and easy" may not be the the most effective; and c) there's no gold standard, and only limited consensus, even in sports where concussion is a very real part of the game.  For cycling, the policy seems "less mature" and perhaps it is time to assess just how head injuries are managed.

Cycling's "fog of war" and who makes the decision?

Having said all this, when a cyclist is completely confused, vomiting, or dizzy and can't remember being in a crash, then by any measure in the world, they should be correctly diagnosed.  In terms of the actual decision of whether a cyclist can continue, I suspect a lot is lost in the "fog of battle".

Not to make excuses, but yesterday, we saw a number of riders down at the same time, and a lot of attention directed at Brad Wiggins, and perhaps the race overlooked the severity of Horner's condition.  Then again, he was treated by the race's traveling medical car, and surely would have shown some symptoms.  I think the complexity comes because of the pressure to make a decision early, the general pressure of being in a race situation where time is of the essence, and also the desire of the rider to continue.

In the interview with Bruyneel above, he explains that Horner was shaken and confused, and people will suggest that perhaps he should have pulled him at the side of the road. We had a discussion on this on our Facebook page earlier today, but the bottom line is that neither the manager or the rider can decide.  The cyclist can't make the call - he is in a classic catch-22 situation because because if they are concussed, then they cannot diagnose it because they're completely unaware of their own symptoms!  

Similarly, the manager is in a difficult situation because he is exposed to all kinds of conflicting incentives - sponsor pressure, race pressure and of course the desire of the rider to continue.  He would also be unsurprised that a rider is "shaken" after a crash, so that alone doesn't constitute a definitive symptom.

In among this "fog of war", he must make a snap judgment, and deal with the pressure from a cyclist who almost certainly will want to continue.  The problem for cycling, then, is that a decision must be made quickly and at the side of the road, and will almost always be made without complete information. Even the sideline type test I mentioned above would take too long - a GC contender can afford only a few minutes before the whole race is compromised.  This further complicates cycling's problem in dealing with any injuries, and is reason why we often see guys soldier on with broken bones before abandoning after the finish line.

Then of course, there is the frightening revelation that sometimes, head injuries can be fatal without producing any cognitive impairments.  Think back to Natasha Richardson, the British actress who died after a head injury sustained during skiing.  She actually sent paramedics away because she felt recovered, and apparently behaved normally, until three hours later when a headache developed.  One day later, she was dead - these are absolutely frightening injuries.  And that's why now, more than ever, the decision must be made on medical grounds, and cycling needs some kind of policy.  But it's no easy solution, simply because of the practical concerns explained above.

To give you an example from rugby, many years of debate and discussion produced a battery of cognitive tests that is administered by neutral specialists, in consultation with the team doctors, before a decision is made.  And the default option is to be safe first, even if it is too conservative.  The player is pulled from the game, and then treated in the relative peace of a medical room.  The same 'luxury' is not true for cycling, and so the focus has seemingly been on diagnosing riders after the stage.  Steffen talks in the article about a modified test that he has developed, and this should probably be standard and Tour-wide, not the responsibility of each team.

That decision should clearly be made in the best interests of the rider - Tour riders will almost always want to continue.  This is true in other sports too, where players often have to be dragged off the field by doctors.  Remember, these are people who don't even know their name, or that they crashed at all, so they clearly can't provide a sound medical opinion that they are clear to continue riding.

Horner's power output data: A great pity to lose out on, but thank you for the openness

And finally, on the note of Chris Horner, it would be remiss of me to mention that Horner's withdrawal is a great shame because he is the most competitive rider in the GC who makes his power output data available.  His performances and numbers are a great barometer for what is really happening at the front of the race, because he has always been within touching distance of the overall leaders and stage winners - 3% here, 5% there.  His data has been fundamental to our analysis of what it takes to climb with the best in the Tour.

This year, his form suggested that he may be even closer, in contention for the whole mountain stage, and so we were looking forward to really seeing what it takes to mix it at the front of the race during high mountain finishes.  His accident and abandon are thus amplified in that it will also cost us the great insight he was helping us gain into Tour power outputs - it is a double shame, and perhaps a good opportunity to thank him for making the data available in the first place.  We wish all other cyclists would do the same.  And we wish Horner well in his recovery, and hope that he receives the very best medical care now.

Wiggins out - collar bone

Another big name out is Brad Wiggins, leader of Team Sky, who was involved in the same crash, but was immediately clearly in trouble.  His collar bone was broken and he was taken away in an ambulance.  For him, it's a huge shame, as it is for all the British hopes for a high overall finish in this year's Tour.  Wiggins' form had never been better, and so his loss will certainly have had an impact on the high mountain stages.

Looking forward

The Tour now heads for the hills, and then the mountains, with two "appetizers" in the Massif Central, and we'll cover any insights as they happen.  Let's hope for minimal negative drama, and that the action happens on the bikes as the race unfolds.