Why Tim Tebow Shouldn’t Play the LSU Game— and Why He Probably Will Anyway

Wow, lol vol should just retire after his or her first post.

-- Joel

There was something about watching a nice guy like Tim Tebow last weekend laid out like a dead fish on ice that bothered me.  Actually, that wasn't what bothered me-- it was listening to Urban Meyer talk about how "terrific" Tebow "looked" (as if he can see his brain) and his insistence that LSU was not necessarily off the table for him.  And he said that right after admitting that Tebow was still having headaches and still can't watch TV or read,  possibly four days after getting hit on the head.  To me that raised a red flag because that means he's still post-concussion symptomatic.

Okay, so I'm not a doctor, but Tebow's plight intrigues me. For one, when I started college, I suffered three concussions in three years, one of which included getting slapped upside the head with a folding chair (yes I was on stage, but no, I wasn't on Jerry Springer).  It's made me naturally curious about getting one's head smacked.  And, since I teach research techniques as part of my job, it's fairly easy for me to turn a vague, passive interest into a dissertation project.  So I did some poking around in the medical journals over the last couple of days just to see where the state of the field lies on concussions.  What I've read suggests that the current "conventional wisdom" on concussions is mostly based on anecdotal evidence; based on this same convention, Tebow might be play-ready in time for LSU.  But a lot of other research coming out suggests that that only a one or two week window to heal might not be what's best for a smacked head.  The medical understanding of concussions is complicated, diverse, and there's no real medical consensus.  On balance, however, it seems that the safe thing would be for Tebow to sit out just one more week; that would put him in a compromise between the different suggested waiting times, and it would also reduce his risk of getting Second-Impact Syndrome if he gets hit hard.  I just doubt that's what he's probably going to do.

So before I continue, let me reassert that this constitutes neither a thorough treatment of the research nor sound medical advice.   I was curious and I was bored.   Are we all clear?  Then let's begin!

Here are some complications of concussions I ran across: 

 

Post-concussive syndrome  (or PCS):  Sometimes the brain recovers slowly from a concussion, which is PCS.  In short, this is a constellation of symptoms occurring after a concussion that can last weeks or months, the result of poor outcome of healing after a concussion.   Usually these include headache and a variety of cognitive and/or emotional dysfunction, like lack of concentration, depression, or irritability.  In one forensic study, (Lovell and Pardini, 2005), PSC symptoms also included dizziness and nausea upon physical activity; their subject had severe PCS symptoms for over a year because she returned to play too early.  For some reason, mild concussions seem to be more of a problem with PCS than severe ones. 

Second-impact Syndrome (or  SIS):  This is every coach's nightmare.  Due to its extreme rarity (something like 50 cases), there isn't consensus over whether or not this is an actual condition or if it's just the result of severe brain injury.  SIS is most likely, according to McCrory and Berkovic (1997), when the injury of an already concussed brain leads to the "rapid development of cerebral vascular congestion which in turn causes increased intracranial pressure, usually resulting in brain stem herniation and death" (677).  Ouch.  In other words, if a concussed athlete jars his head a second time, sometimes the brain squeezes itself to death shortly after the athlete gets to the sideline.  According to some of the literature, though, you don't actually have to hit your head a second time to trigger SIS; simply jarring the athlete from the side or from behind (i.e., getting sacked) might be enough to set it off.  The good news is that, from the case studies I saw, SIS mostly occurred in victims who had concussions less than 10 days apart, although the literature says they could be at risk for up to three weeks. 

Dementia Pugilistica:  Punch-drunk.  This seems to be a severe and irreversible decline of mental function (coordination, dementia, tremors, slurring of speech, etc.)  which occurs up to decades after the onset of repeated trauma and looks a little like Parkison's.  It's probably from repeated concussions and mostly experienced by boxers (and hence the name).  There's a line of thought that suggests that professional football players often suffer from this concussive syndrome or something like it (and hence the NFL's interest in concussions). 

So, that's what's at stake.  Now, let's talk about the literature:

I.  How well understood are concussions? 

Actually, they're not really well understood at all.  For one, since medical ethics prevents us from smacking athletes upside the head with a 2 x 4 to see what happens, researchers have to find their concussions after-the-fact.  Second, concussions are a rare event.  People just don't "get their bell rung" very often, so sample size can be very small-- and SIS (second-impact syndrome) is even more rare still; oh, and since most of them die immediately you don't have a lot of SIS test subjects.  Third, concussions are under-reported.  Not everyone might realize that they have a concussion when they hit their head, and if a player knows they're going to get pulled from a game, they just might downplay their symptoms (In fact, one study suggests this is very often the case).

Also, trying to see a concussion sometimes is like trying to take a picture of the wind: you can't see the thing; can only see its effect. Physical scans, like Tebow's CT scan, seem to only be useful for diagnosing worst-case scenarios with concussions because they can't see damage on a cellular, metabolic or an axon level.  This is why "a negative finding on a CT scan, MRI, etc. does not rule out concussion, and should not be the basis for determining if an athlete is ready to return to play" (Collins & Pardini, 2007 p. 184-5). The damage done in a concussion is often invisible and only inconsistently detectable by symptoms-and if you have a combative patient who really doesn't want to get sidelined, (like a certain gung-ho QB in his last year), you might not get an accurate reporting of symptoms, either.    Cognitive and neurological tests are, it seems, a much better judge of impairment. 

So the very nature of concussions makes them hard to study and harder to classify.  But, do the studies we have come to any sort of consensus?   From what I've read, researchers don't agree on much, even on the definition of a "concussion," and they especially don't agree on return-to-play time for athletes.  For instance, most of the concussion scales (see below) use loss of consciousness (LOC) as a criterion for diagnosing severe concussions.  But at least one study  (Hinton-Bayre & Geffen, 2002) suggests that this is a red herring because long-term effects of concussion don't line up with LOC.   For another, there is a lot of disagreement about return-to-play for the most severe category, anywhere from 2 weeks to a month.  This is because different studies have demonstrated different healing rates for a concussed brain, anywhere from days to weeks to months (See Meyers, 2008 for a nice chart of recent studies showing longer healing times).

One thing that surprised me is that I can't find any longitudinal studies of athletes and concussions.  (They might be out there-I just couldn't find them.)   Actually, this makes sense if you think about it-- conventional wisdom about concussions has only shifted in the last 20 years or so, and it takes time to get enough data and funding to do something like that.  The only good info I could find was an article about a telephone survey of NFL retirees, which found alarmingly high rates of mental dysfunction in concussed athletes later in life.   But even the study admits that this form of study isn't exactly clinically rigorous.  What this means is that we only have a vague idea of how concussions will affect an athlete later in life, but we don't like what we do see.   There's a high incidence of emotional and cognitive disorders among multiple-concussed athletes once they retire. 

There is some agreement on a few things so far.  The brain is delicate, and the concussion often causes damage, not necessarily on a structural, but on a cellular level where it's hard to detect.   "Getting over" a concussion is much less a matter of losing the symptoms as it is the brain healing over, which might take much longer than we expect.  Multiple concussions are really bad news.  Finally, returning to sport too early might slow down the brain's recovery time from a concussion. 

II.  There is no consensus on return-to-play time. 

So how long should Tim Tebow stay out of the gym and the practice field?  Ultimately, that's up to his doctors.  But how do they try to figure that out?  Their decision is based on a lot of things, but often times the decision comes down to playing it safe and picking a return-to-play time that will ensure that your athlete has fully recovered.  So a lot of different grading scales have been created to evaluate the severity of a concussion and determine return-to-play time.  Here is a slimmed-down summary of the most common I've found: 

                                                                                                                                                                                                                                                                                                                                                   

	Symptom:	Class 1	Class 2	Class 3	[Class 4]
Cantu (2002):	Symptomatic?	Less than 30 min	More than 30 min.	Longer than 7 days
	Amnesia?	Less than 30 min	Between 30 min. and 24 hr.	More than 24 hr.
	LOC?	none	Less than 1 min.	More than 1 min.
Jordan (1994):	Confused?	Yes	Yes
	Amnesia?	No	Less than 24 hr.
	LOC?	No	No	Yes; with altered level of consciousness less than 2-3 min.	Yes; with altered level of consciousness more than 2-3 min.
Colorado Med. Society (1991):	Confused?	Yes	Yes
	Amnesia?	No	Yes
	LOC?	No	No	Yes
AAN (1997):	Confused?	Yes; less than 15 min.	Yes; more than 15 min.
	LOC?	No	No	Yes

LOC= Loss of Consciousness ;   PTA= Post-Tramautic Amnesia; PCSS= postconcussion signs and symptoms
(A good chart with eight different scaling methods can be found in Cantu, 2002.) 

 

Okay, so this is extremely simplified, but it gives you enough info compare the different methods.  I see the most references to the Cantu, AAN, and Colorado scales. The Cantu scale has two versions between an earlier model and an experiential model from 2002; they split levels II and III at 5 minutes LOC and 1 minute LOC, respectively.

So, what would each scale recommend for Tim Tebow?  It all comes down to whether or not you think he lost consciousness, and for how long.  Personally, looking at the footage, it looks like he blacks out to me a couple of seconds after hitting the grass.  The players start poking at him and there's no response at all.  The trainers start talking to him after fifteen seconds, but you can't see a response.  I think he's for sure awake after one minute, though, and he gets up after two minutes.  Here's how I'd score his RTP by different scoring methods: 

Cantu (2002):      Class 2 or 3; maybe up to 1 month (class 3), but must be asymptomatic for 1 week (class 2).

Cantu (1991):       Class 2; must be asymptomatic for 1 week. 

Jordan (1994):      Class 3 or 4; one month wait, must be asymptomatic for either 1 week (class 3) or 2 weeks (class 4). 

Colorado (1991):   Class 3; 1 month wait, must be asymptomatic for 2 weeks

AAN (1997):          Class 3; 2 week wait. 

So, take your pick. One should note that two of these (Cantu 1991 and AAN) both recommend 1-2 weeks before returning an athlete with Tebow's presumed level of concussion to the field.  So much the better for Meyer-- that means that Tebow should be "fine" for play just in time for the LSU game, two weeks after his head injury.  But note that two other scales-the Jordan and Colorado-recommend a return-to-play time of at least one month for players with LOC.   But also keep in mind that Cantu seems to have revised that scale-if Tebow was out for longer than one minute (and he might have been), or that pesky post-concussion headache lasts for a few more days, the Cantu 2002 scale says he should be out for a month as well. 

Then there's that headache and inability to focus to consider.  Let's assume for the sake of argument that they decide to keep him out for two weeks, until the LSU game.  The problem is that, depending on when Meyer visited him, he was likely still symptomatic on Wednesday. The Cantu, Jordan, and Colorado all recommend measuring from cessation of symptoms.  So if we count two weeks from Thursday, assuming a cessation of symptoms, he shouldn't be in the LSU game anyhow.  If it lasts until Saturday, he won't even make it to the one-week window.

But as it turns out, the Jordan and Colorado scales aren't the only ones that recommend the 1-month wait.  Mayers (2008) recommends a 4-6 week return-to-play period, something that hasn't exactly gone over well with a lot of medical professionals and coaches.  He bases his suggestion on the fact that a lot of the most recent studies measuring concussions in athletes show a rate of healing from the damage that goes fairly consistently beyond the 1-2 week waiting period-- sometimes months beyond  (see p. 1161).  So he thinks that two weeks is simply not enough for many concussed athletes to heal, and a lot of people disagree.

But now I'm going to complicate things even more.   Now that we've discussed the tables, you should know that there is another line of reasoning that essentially finds them misleading.  After all, the scales are "are not fully researched, but rely on professional judgement" (Erlanger et. al, 1999, p. 199).  Since concussions are highly individualistic (age of player, location of injury, force of impact, etc.), some recommend an individualistic approach and/or using a gradual step-up of physical activity as a way to determine if someone's ready to return to play.  If an athlete stays asymptomatic after a gradual resumption of activities, they're usually considered good to go. But also keep in mind that that a lack of physical symptoms does not mean that the concussion is necessarily healed; that's also why a lot of people still have a waiting period established for after symptoms disappear and rely on cognitive tests instead.   

(This article, incidentally, cites Robert Cantu, the creator of those Cantu scales above-- and he weighs in on Tebow's concussion.)

 

Conclusion:

If there's anything I want you to get from all this, here it is:  researchers are just now learning about how the brain is behaves when concussed, and the results are consistently challenging the idea that there's such a thing as "just" a concussion.  Secondly, the most recent studies are suggesting that the current return-to-play paradigm in most sports in regard to concussion might not be long enough or based on the wrong things.  Keep in mind: you can't always "see" or "measure" the amount of damage involved with a concussion; CT scans may or may not give enough info to diagnose brain concussion. That's what cognitive tests are for.   And the results of returning an athlete to play too early to the game might not crop up until years later (as with dementia pugilistica) or, tragically, somebody gets hit just the right way and they die of SIS on the sideline. So if it were my kid, (which it's not,)  I personally would take the safe route and, knowing that Tebow probably has at least a Class 2 to Class 3 concussion, I'd take the more conservative estimate of a two week asymptomatic waiting period-- after the LSU game.  After all, it's one thing to play Russian roulette; but it's a whole different game if you don't even know whether you're playing it with a revolver, a muzzle loader, or a potato gun. 

That's why I think Urban Meyer ought to play it safe with the noggin of his star quarterback.  On the one hand, he has an excellent staff of doctors at his disposal; they're doing both baseline and cognitive testing, the good, hard-core tests to determine concussive symptoms.  So they're doing it right; they're not basing their decision on his symptoms alone, and that's fantastic.  But on the other hand, if you take any three specialists on concussions, depending on the literature they read, you might get three different answers.  Return-to-play times are highly subjective anyhow.  When it's all said and done, you have to go with your gut; mine says to play it safe.  What will Tebow and Meyer's gut tell them?  That's why I fear that Urban Meyer will probably wait the customary, felicitous two week RPT before sending Tebow and his bruised watermelon of a head back in against the LSU Tigers.   And I, along with the rest of you, will be holding my breath hoping that the watermelon doesn't get cracked.

 

A list of my main references:

Cantu, R.C. (2002). Posttraumatic retrograde and anterograde amesia: pathophysiology and the implications in grading and safe return to play.  Journal of Athletic Training 2001:36:244-8. 

Collins, M., & Pardini, J.  (2007).  Concussion.  Current Diagnosis and Treatment in Sports Medicine.  Ed. P. Mahon.  New York: Lange Medical Books/McGraw Hill.  180-93.

Colorado Medical Society. (1991). Report of the Sports Medicine Committee; Guidelines for the Management of

Concussion in Sports (revised). Denver: Colorado Medical Society.

Davis, M., Davis, P, & Ross, D.  (2005). Expert Guide to Sports Medicine.  Philadelphia: American College of Physicians.

Erlanger, Kutner, Barth, and Barnes. (1999). Neuropsychology of Sports-Related Head Injury:  Dementia Pugilistica to Post Concussion Syndrome.  The Clinical Psychologist 13.2, p. 193-209.

Echemendía, R. (2006).  Return to play.  Sports Neuropsychology: Assessment and Management of Traumatic Brain Intury.  Ed. Ruben J. Echemendía.  New York: Guilford Press, 2006.  112-128. 

Jordan, B.D. (1994). Sports injuries. National Athletic Trainers' Association Research and Education Foundation.

Proceedings, Mild Head injury in Sports Summit, Washington DC.

Lovell, M., & Pardini, J.  (2005).  A rising star too quickly fades: mismanagement of sport-related concussion.  pp. 118-131 in:  Forensic Neuropsychology Casebook, ed. Heilbronner, R.  New York: Guilford Press.

Meyers, L. (2008).  Return-to-play criteria after athletic concussion: a need for revision.  Archives of Neurology 65(9): 1158-61. 

Quality Standards Subcommittee of the American Academy of Neurology (1997). Practice parameter: The management of concussion in sports.  The American Academy of Neurology.