“The perfect storm of high-profile cases in youth and professional sports, military actions in Iraq and Afghanistan, media attention, and public fascination with the National Football League (NFL)”—that’s how Richard Ellenborgen, MD, chair of the department of neurological surgery at the University of Washington and co-director of the Seattle Sports Concussion Program, described the evolution of concussion from an “invisible injury” to the focus of much scientific and nonscientific attention. Current events and the response of the NFL, the National Institutes of Health, and the Centers for Disease Control and Prevention (CDC) have resulted in research, education, and advocacy concerning concussions at all levels of sports.

Frequency of concussions in sports
According to Dr. Ellenborgen, concussions are the number one cause of death and disability in adolescents worldwide. CDC data show 275,000 hospitalizations and 52,000 deaths attributable to traumatic brain injury in 2011.

The impact of concussion in sports was reinforced by Ann McKee, MD, co-director of the Center for the Study of Traumatic Encephalopathy at Boston University. By October 2013, she had examined the brains of 46 deceased former NFL players and determined that 45 had chronic traumatic encephalopathy (CTE), a progressive degenerative disease of the brain found in individuals with a history of repetitive brain trauma, including symptomatic concussions as well as asymptomatic subconcussive hits to the head.

When asked what percentage of NFL players probably have CTE, Dr. McKee responded, “I don’t think everybody has it, but I think it’s going to be a shockingly high percentage.”

Even more alarming, a recent study found that high-school football players are nearly twice as likely to sustain a concussion as are college players.

Recognizing the problem
Early recognition and appropriate return to play are key to reducing the morbidity associated with concussions. Despite their frequency, concussions continue to be poorly understood by both lay people and medical professionals.

Even though all concussions may share some common features—rapid onset of symptoms, association with neurological impairment, spontaneous resolution, evolution over time, range of clinical symptoms—each injury is unique. Early criteria were loss of consciousness and amnesia, but fewer than 10 percent of sports concussions involve loss of consciousness and probably a third do not produce amnesia.

“Signs and symptoms suggestive of concussion are many and varied,” said Dr. Ellenborgen, “and injured athletes show different combinations and severity of these.”

Efforts to quantify, evaluate, and track concussion symptoms on a more objective basis have resulted in the development of a number of tools. Most professional sports teams administer preseason examinations to set a baseline against which later exams can be measured. Jimmie Mancell, MD, a team physician for the National Basketball Association’s Memphis Grizzlies, noted that preseason assessments are done in a quiet, distraction-free environment, and postconcussion evaluations should be performed in a similar setting. For evaluation of possible concussion during practices or games, a shorter version of the assessment is used.

According to Brandon Baughman, PhD, a neuropsychologist, “one size does not fit all” when it comes to assessment. “Assessments should be multilevel, depending on the time from injury,” said Dr. Baughman. “Although trained personnel can effectively administer a test, the results should ideally be interpreted by a neuropsychologist or someone with training in clinical neuroscience and psychometrics. Cognitive recovery may precede or follow clinical symptom resolution, and neuropsychological testing can contribute significant information.”

A recent study of 138 junior and senior high school female cheerleaders appears to confirm this: 37 percent of those who reported no increased symptoms at postinjury evaluation had at least one abnormal ImPACT (Immediate Postconcussion Assessment and Cognitive Testing) composite score, suggesting some residual cognitive decline compared with baseline.

Regardless of the assessment tool used, or even if no test is used, according to Dr. Ellenborgen, the new guideline for athletes at all levels is: “When in doubt, sit them out.” Even the U.S. military has its catchy slogan for personnel with traumatic brain injuries from improvised explosive devices (IED): “IED—take a knee.”

Return to play
Although immediate removal from participation after a concussion is universally accepted, the timing of return to play is less definite. Assessment tools can be useful in decision-making, but there are no clear-cut guidelines as to when it’s safe to allow an athlete to resume full activity.

Dr. Ellenborgen described the following six stages of rehabilitation:

• no activity
• light aerobic exercise
• sport-specific exercise
• noncontact drills
• full contact practice
• full return to play

Depending on the severity of symptoms, modifications may be needed in the athlete’s school environment and schedule.

One of the most far-reaching aspects of the return-to-play issue is the enactment of legislation to protect young athletes. Before the media focus on the fate of NFL players increased awareness and pressure on lawmakers, only six states had such legislation. Currently, all states except Mississippi have passed laws, most of which mandate that any child who sustains a concussion must be immediately removed from play and must be cleared by a qualified health professional before returning to sports.

Legislation in most states is modeled after the Lystedt Law, named for a middle-school football player, Zackery Lystedt, who was permanently disabled after returning to a game with a concussion. The legislation generally mandates education for coaches, athletes, and parents and a signed parental consent form acknowledging their receipt of information about concussions and the risks of concussion involved with sports activities.

According to Paul Klimo, MD, a pediatric neurosurgeon, great variation exists among state laws: Fewer than half require formal training for coaches, 2 percent require removal from sport only if the athlete loses consciousness, and 5 percent have no removal criterion.

The impact of culture
Despite increased awareness of the consequences of repeated head trauma, the culture among athletes resists the self-reporting of concussions. A recent report by the Institute of Medicine noted that young players “profess that the game and the team are more important than their individual health and that they may play through a concussion to avoid letting down their teammates, coaches, schools, and parents.”

“It’s all about the kids,” Dr. Ellenborgen concluded. “Athletes and their parents should ask themselves, ‘What is this game worth? The rest of the season? The rest of the athlete’s career? The rest of the athlete’s life?’

“Not allowing an injured athlete back into practice or games until he or she has been evaluated and cleared by a licensed healthcare provider trained in the evaluation and management of concussions is not only the law, it’s the right thing to do.”

Disclosure information: Ms. Daugherty—No conflicts.

Kay Daugherty, BS, is the medical editor for the Campbell Foundation.

Bottom Line

• Concussions sustained during sports have gone from “invisible” injuries to the subject of much scientific and nonscientific research.
• Early recognition and appropriate return to play are key to reducing the morbidity associated with concussions.
• Practically every state has passed legislation mandating immediate removal from play of youths who sustain concussions and assessment before return to play.
• The future of contact sports may depend on the response by parents and players.