Return-to-Play After Concussion: Clinical Guidelines for Young Athletes

Defining and Diagnosing Concussion

A concussion is a mild traumatic brain injury that can result in amnesia, confusion, and loss of consciousness. Contrary to common belief, any amnesia or confusion after a head injury is consistent with a concussion even without loss of consciousness. Approximately 10% of persons with concussion do not lose consciousness, which may lead to underreporting and underdiagnosis.³ Concussions can produce immediate, subacute, and chronic cognitive, behavioral, social, occupational, and academic impairment. The neurophysiologic symptoms are a manifestation of pathologic changes at the microscopic level that disrupt normal neurophysiologic dynamics. The consequences are additive, and each successive concussion results in an increased level of damage to the cerebrum, causing further neurocognitive impairment and is thought to lead to chronic traumatic encephalopathy (CTE).

Our understanding of concussion is continuing to expand, with new discoveries that will help physicians diagnose concussion with objective biochemical laboratory tests in addition to classic clinical assessment. It was long believed that concussion was strictly a functional and not a structural injury because of the grossly negative findings on imaging obtained during the immediate postinjury period. We now have a better understanding of the structural consequences thanks to advances in research and the advancement of neuroimaging modalities such as magnetic resonance imaging and diffusion tensor imaging, which have shown chronic manifestations of concussion involving white matter tracts in patients with a history of concussion.⁴ New tests have been developed to assess injury at a cellular level.⁵ In February 2018, the US Food and Drug Administration approved a novel blood test, the Brain Trauma Indicator (Banyan Biomarkers), to evaluate the presence of mild traumatic brain injury and concussion. This test measures the serum levels of the proteins ubiquitin carboxy-terminal hydrolase L1 and glial fibrillary acidic protein, which are released into the bloodstream after the brain sustains an injury.⁵

Grading Concussion and Determining Return to Play

At least 41 different grading systems have been used to classify the severity of mild traumatic brain injury documented in the literature.⁶ Currently, the most widely used and accepted clinical guidelines were developed by the Colorado Medical Society, the American Academy of Neurology (AAN),⁷ and Cantu⁸ (Table 1). Loss of consciousness is considered a grade III concussion in these grading scales.⁹ The Colorado Sports Concussion Grading Scale incorporates the concepts from most grading scales, producing a progression of severity (grades).

The return-to-play guidelines incorporate the grade of concussion, number of prior concussions, and time between concussive episodes and the patient's postconcussive performance on neurologic, physical, and neuropsychologic examination. The return-to-play guidelines in Table 2 are based on the most recent grading system of the AAN and are recommended for physicians to determine an athlete's ability to return to play.⁷

Contrary to the AAN's use of concussion grading scales, the International Conference on Concussion recommends against using standard grading scales to ensure individualized care.¹⁰ A stepwise approach to recovery is based on the Concussion in Sport Group's “11 R's”: recognize, remove, reevaluate, rest, rehabilitation, refer, recover, return to sport, reconsider, residual effects and sequelae, and risk reduction. This approach incorporates neuropsychiatric testing using tools such as the Standardized Assessment of Concussion and the Maddocks Questions Test. The fifth International Conference on Concussion in Berlin recommends a graduated return to sport, with each step encompassing 24 to 48 hours.¹¹ In addition, they recommend the use of the latest Sport Concussion Assessment Tool, as it is the most developed and established tool for evaluating concussion within the first 3 to 5 days.¹¹ For graduated return to sport, they recommend the following:

• Symptom-limited activity

• Light aerobic exercise

• Sport-specific exercise

• Noncontact training drills

• Fully contact practice

• Return to sport

The American Osteopathic Association also issued guidelines pertaining to return to play activity following concussion in Resolution No. H 352.¹²

▪ Young athletes with concussion should stop playing the sport immediately.

▪ Sideline assessments for athletes with suspected concussion should be performed by appropriate licensed/certified professionals.

▪ If concussion is suspected after assessment, athletes should be examined by a physician.

▪ Physician will develop treatment plan for return to sport and return to learn.

A study¹³ performed at the University of Pittsburgh Medical Center found that young athletes who continued to play a sport immediately after a concussion took twice as long to recover from their symptoms and had more severe symptoms compared with an equivalent group removed from play. Removal from play was the strongest predictor of a fast recovery, more so than any other factor, such as age or sex.

At the start of the athletic season, all athletes should receive baseline testing that evaluates their balance and cognitive function. For athletes who later sustain a concussion, these baseline assessments can be compared against postconcussion testing to determine whether their function has been affected. When the results of cognitive, physical, neurologic, and neuropsychiatric examinations are in doubt, players should be removed from play.

Return to Learn

The CDC released official return-to-learn guidelines in 2017 that specifically addressed the cognitive and emotional consequences of concussion.¹⁴ Concussion can cause residual difficulty with focus, memory, task completion, goal-oriented behavior, irritability, somnolence, fatigue, emotional lability, headache, photophobia, nausea, and disequilibrium. The CDC's return-to-learn guidelines are based on the level of residual symptoms the patient experiences. A more comprehensive review of these guidelines can be accessed at https://www.cdc.gov/HEADSUP/.

Severe Outcomes of Concussion

Conclusion

Physicians who evaluate young patients with concussion can protect them from sustaining further injury by using the return-to-play guidelines and educating patients and their families. When implemented, these clinical scales and guidelines can prevent secondary injury and improve the ongoing care and long-term outcomes of these patients. We recommend that parents, guardians, and students learn about the health risks and warning signs of concussion through evidence-based information disseminated by schools and youth sports organizations. (doi:10.7556/jaoa.2019.135)

Author Contributions

All authors provided substantial contributions to conception and design, acquisition of data, or analysis and interpretation of data; all authors drafted the article or revised it critically for important intellectual content; all authors gave final approval of the version of the article to be published; and all authors agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.