Recently in Sports medicine Category
Among the disturbing facets of the NYT coverage, NHL commissioner Gary Bettman downplays the risk of brain injury as a result of brawling in his league* and minimizes the Center's research as "preliminary" and "great for headlines." One is reminded of neurologist Ira Casson's essential denial of the association between repetitive head injury and CTE in January of 2010. Casson was co-chairman of the NFL's panel on brain injury until he resigned November of 2009, largely owing to his perceived insensitivity toward a possible link.
* The Center's case series of NFL players with CTE, 13 of 14, is substantially larger.
** Which he, inexplicably, denies is allowed.
As far as Vick returning to play, I suspect it will be soon, given a review of the videotape footage. It was a lateral helmet-on-helmet blow (with his own teammate!), followed by a bit of quick head torquing to the left—the latter of which is what probably rang Vick's bell.
* And given the bounty of narcissism in the NFL, it is probable that narcissistic assholes will finish first.
Although
I would argue that any athlete who is suspected of sustaining a brain injury should be eliminated from further play, regardless of the outcome of any sideline assessment, a new, brief test may provide a practical way of assessing sports-related head injuries on the fly.Writing in this week's Neurology, researchers from the University of Pennsylvania and various Illinois facilities report on the utility of the 2-minute King-Devick test, which requires a brief series of rapid left-to-right number readings. In a study population of 39 boxers and other "mixed martial arts" fighters (nearly all of which were male), K-D test performance, measured in seconds, deteriorated significantly from baseline after some kind of head trauma (~11-second worsening) and even moreso after loss of consciousness (18-second worsening) during bouts. (Fighters without injury actually showed minor post-play improvement in their test scores.)
K-D tests results, importantly, also appeared to correlate well with outcomes of another validated, but more extensive, sideline test for head injury: the SAC portion of the Military Acute Concussion Evaluation (MACE).* The K-D authors report that prospective studies of athletes at the University of Pennsylvania are ongoing, to establish, among other things, norms of testing.
One ethical concern that I have with this intriguing study, however, is the use of boxers as subjects, an act that ostensibly endorses—or at least, turns a blind eye to—a sport that outrightly promotes head injury. I would've had fewer qualms about a study of a sport that doesn't intend head injury as an object of so-called play.
Another note: One of the coauthors, optometrist and entrepreneur Steve Devick, has a patent pending on the K-D test, which can be bought online in various plan packages (from "family" to "organizational") for $50-$1000. According to a 2004 profile piece in the Magazine of the University College of Optometry, Devick and Alan King invented the K-D test when they were fourth-year students at optometry school in 1976. As the story goes, they flipped a coin to determine whose surname would come first in the test's label.
The K-D test has a long history of being administered to early grade-school kids to assess rapid eye movements and their potential relationship to reading performance; however, the reliability of test results in this setting has been called into question.
SAC = Standardized Assessment of Concussion.
* My understanding is that the NFL uses the much-more complex and computerized Immediate Post-Concussion and Cognitive Testing [ImPACT] assessment off the field in its vulnerable players.
No. 9: Sports-Related Concussions—No More Walking It Off
Despite the fact that neurologist Ira Casson, former co-chairman of the NFL's panel on brain injury, essentially denied a relationship between repeated head injury and lasting brain damage in January,* the prevailing zeitgeist 11 months later is this: That sports-related concussions should be taken very seriously, and that safeguards should be in place to allow for recovery—at all levels of play.
Casson's functional denial was based on the fact that scientific data are limited on the subject, but that deficiency is being answered by clinical and pathologic studies from, among others, investigators at the Center for the Study of Chronic Traumatic Encephalopathy (CTE)—the raison d'etre of which is to examine the very issue of CTE in sports and, by extension, to be an advocate for athletes who put themselves at risk of acute or chronic brain injury.
The Center's latest, and perhaps most controversial, proposal is that the CTE associated with collision sports increases the risk of motor neuron disease (aka ALS, aka Lou Gehrig's disease). Ongoing data from others, which were highlighted in a recent, dedicated issue of Sports Illustrated, suggest that the risk of lasting brain injury is not confined to concussed players, but that functional damage can be demonstrated in completely asymptomatic jocks who've sustained nonconcussive head blows.
Of course, the study of sports-related head injury is nothing new—despite the rising sensitivity to its potentially lasting consequences among NFL officials specifically and the general public, well, generally. A PubMed search with the terms "concussion" and "football" produces 273 English-language articles, dating back to 1970 (when Brett Favre was just a wee babe!). About three quarters of these articles were published within the last 10 years.
A historic gem from 1983 ("Concussion incidences and severity in secondary school varsity football players") provides the results of a survey of more than 3000 high school football players in Minnesota, circa 1977. In the age of overtly endorsed disco and surreptitiously endorsed butt-blocking and face-tackling, the concussion rate was 19%, and nearly 70% of affected athletes returned to play the same day. A prior history of concussion was found to increase the risk of subsequent concussion 4-fold. As a result of head trauma, 6 high schoolers sustained permanent disability, ranging from "extensive" brain dysfunction to quadriplegia to death.
* In front of a House Judiciary Committee, no less.
The rising interest in brain injury among American football players has spilled over into Sports Illustrated. In the November 1 issue, out today, writer David Epstein profiles a complex study conducted by Purdue researchers, who fitted 11 Indiana highschoolers' helmets with impact sensors. Using the NFL-endorsed ImPACT neurocognitive test and fMRI, the researchers determined, to their surprise, that repetitive nonconcussive* head blows are not without consequence. The visual memory scores of some players who sustained these types of hits,** usually frontal and often exceeding 100 Gs, dropped significantly and appeared to correlate with changes in fMRI brain activity (in the dorsolateral prefrontal cortex).
The disturbing finding: On the sidelines and off the field, these players were clinically asymptomatic, at least by crude measures. They could carry on conversations, did not demonstrate memory impairment, and appeared to be fine by their parents' observations.
The reassuring finding: These players' ImPACT scores returned to baseline off-season.
The remaining uncertainty: No one really knows what the long-term toll of repetitive, nonconcussive, frontal head blows is, season after season. The Purdue researchers hope to follow up their subjects throughout their high school athletic careers and perhaps into college.
In addition to SI coverage, the Purdue study was published in the peer-reviewed Journal of Neurotrauma last month.
fMRI = functional MRI.
* Meaning, not impairing consciousness.
** Frontal head blows can be distinguished from the brainstem-torquing side blows associated with concussion.
Ira Casson—neurologist, former co-chairman of the NFL's panel on brain injury, and target of yesterday's House Judiciary Committee hearing on football-related concussion—is technically correct: Data linking repeated head injuries in American football to lasting brain damage are limited.
But as they say, absence of evidence is not evidence of absence. Moreover, a link is highly plausible, given the well-described association between repetitive brain injuries in boxing and neurologic deterioration—aka dementia pugilistica.
To remedy the shortage of evidence on sports-related head injury, the nonprofit Sports Legacy Institute partnered with the Boston University School of Medicine in 2008 to create the Center for Traumatic Encephalopathy. The Center's raison d'etre is to assess neuropsychiatric symptoms in athletes and to examine their donated brains for pathologic signs.
The Center's most recent publication, printed in July of 2009, provides a review of 48 cases of neuropathologically verified chronic traumatic encephalopathy, or CTE, in the medical literature and adds data from 1 professional football player and 2 boxers. The clinical picture of CTE features memory loss, behavior and personality changes, speech problems, parkinsonism, and other gait or movement disorders.
Pathologically CTE is typified by nearly global brain atrophy and the accumulation of tau protein in neurofibrillary tangles. Consequently CTE is classified a tauopathy, like other neurodegenerative disorders (including Alzheimer disease); however, CTE can be distinguished from other tauopathies, the authors claim, by its predilection for certain brain areas (eg, the superficial layers of the cerebral cortex). Deposits of amyloid beta, typically in the form of plaques and characteristic of AD, are evidently not as common in CTE.
In December, the Center also described postmortem CTE in an NHL player. In an effort to accumulate more data, the Sports Legacy Institute encourages athletes to donate their brains to the Center. Current Legacy donors are listed at the Institute's website, along with links to their stories. Several of these cases were discovered by pathologist Bennet Omalu* and colleagues, who recently reported microscopic evidence of CTE in 5 professional athletes who attempted or committed suicide at relatively young ages.
* Omalu is the author of Play Hard, Die Young: Football Dementia, Depression and Death.
01/06/10 addendum: While the effects of performance-enhancing drugs (eg, anabolic steroids) on mood and personality are well known, their role in the development of CTE is debated—largely because data in that area are lacking as well. The NFL case report described recently by the Center (former linebacker John Grimsley) indicated no reported use of performance-enhacing drugs (if you believe that a linebacker can escape the NFL without having used them).
The role of the apolipoprotein E (ApoE) genotype in CTE appears to be more significant, however. Of the 10 CTE case reports in which ApoE genotyping was performed, half carried at least one APOE ε4 allele—a known genetic risk factor for Alzheimer disease. The authors suggest that ApoE ε4 carriers may be more susceptible to CTE.
The 50-game suspension handed down yesterday to the LA Dodgers' power hitter Manny Ramirez brings another performance-enhancing drug to public attention: human chorionic gonadotropin, or hCG. Best known as the hormone assayed in urine or serum to confirm early pregnancy, hCG is used to treat infertility in women by stimulating ovulation (eg, Pregnyl; Organon). In men, the substance is also injected to treat infertility or to reverse hypogonadism; the hormone stimulates the testicular Leydig cells to produce testosterone.
But because hCG is less efficient than anabolic steroids for increasing muscle mass,* it is most likely injected by power athletes to treat androgen-induced hypogonadism, either during or after a course of anabolic steroids. The substance, consequently, is an indirect indicator of steroid abuse.
In healthy males, hCG normally occurs at low, but measurable, levels in serum or urine, and serum assays are sensitive. However, most doping surveillance tests are performed on urine, and the suitability of the assay in this context has not been defined, according to a recent report. No matter for Manny. His penalty for hCG doping was reportedly based on evidence in his medical files, not on a positive drug test, according to the NYT.
* hCG is also more expensive than anabolic steroids, but what does that matter to an MLB player.
Image of chorionic gonadotropin preparation from APP Pharmaceuticals.
D'oh! Just when you thought you dodged an IOC bullet, the overseer of the Olympic Games announced yesterday that it will further analyze blood and urine samples collected from athletes at this summer's Beijing games. First on the retroactive testing list is Roche's long-acting red-cell booster Mircera.* But the IOC also warns that it will store the Beijing samples for 8 years to enable additional analyses when new drug tests become available.
In Beijing, 4770 doping tests were conducted on blood or urine, covering the period from July 27th to August 24th. But only 6 out of approximately 11,000 athletes suffered sanctions as a result of positive tests, an unexpected, low number (Table). Therefore the IOC will retest samples with a recently validated assay for Mircera. The announcement comes on the heels of news this week that 3 more Tour de France racers tested positively for the substance.
|
Disqualified Athlete |
Country |
Sport |
Highest Placement |
Detected Substance | |
|
1 |
Lyudmila Blonska |
|
Heptathlon |
2nd |
|
|
2 |
Igor Razoronov |
|
Weightlifting |
6th |
|
|
3 |
Fani Halkia |
|
Hurdles |
— |
|
|
4 |
Jong Su Kim |
|
Shooting |
2nd |
|
|
5 |
Isabel Moreno |
|
Cycling |
— |
|
|
6 |
Thi Ngan Thuong Do |
|
Gymnastics |
15th |
|
(IOC decisions regarding 3 other alleged Olympic doping cases, Belarussian hammer throwers Vadim Devyatovskiy and Ivan Tiskhan [testosterone] and Polish kayaker Adam Seroczynski [clenbuterol], are pending.)
* A pegylated version of recombinant erythropoietin.
Image of a freakishly bulked-up Lyudmila Blonska from Wikipedia.
At Saturday's Olympics, the black, vaguely calligraphic design on the shoulder of volleyballer Kerri Walsh most certainly prompted the following question in a range of languages: What the hell is that?
A few curious Web posters thought it might be a fierce tattoo. But no, NBC's Olympics coverage says it's black Kinesio tape on Walsh's right shoulder, which was surgically treated last winter. One commentator said the tape eases pain, stabilizes joints, increases circulation, and reduces lymphedema. If so, that's some tape.
The official web site for the product emphasizes the benefits of the tape—it's particularly elastic and sticky—and the all-important taping method—which accounts for the funky design on Walsh's shoulder. The 4-inch-wide tape can be cut lengthwise for "Y" applications (which are designed to stabilize muscle or prevent its contraction or otherwise do something nice), like that along Walsh's scapular spine and posterior deltoid (see graphic below). In Walsh's case, another Y application was applied to her middle deltoid, along with uncut tape that crisscrossed the joint. Kinesio tape evidently comes in a variety of colors, which (as far as I can tell) are for fashion purposes alone—or in the case of black, to intimidate.
The Kinesio web site claims that taping "alleviates pain and facilitates lymphatic drainage by microscopically lifting the skin. The taped portion forms convolutions in the skin, thus increasing interstitial space. The result is that pressure and irritation are taken off the neural and sensory receptors, alleviating pain. Pressure is gradually taken off the lymphatic system, allowing it to channel more freely." Nice-sounding words to the medically uneducated, and bullshitty to the rest of us. Moreover, I'm not entirely sure how one would even go about proving these physiologic effects.
Evidently only one randomized clinical trial has been conducted to evaluate Kinesio taping for any musculoskeletal condition. A quasi-double-blind* study, published just last month in the Journal of Orthopaedic and Sports Physical Therapy, assessed the short-term self-reported effects of Kinesio or sham taping in 42 young adults with rotator-cuff conditions. The investigators observed immediate improvement in pain-free shoulder abduction with Kinesio taping but no other statistically significant benefit (range of movement, pain, or disability) over sham taping during a 6-day treatment period. The authors suggest why Kinesio taping may improve immediate pain-free movement (gate-control theory, anyone?) but acknowledge their complete speculation on the subject.
* One author was blinded to the taping methods used, and taping methods were different between Kinesio and sham subjects.
