Concussions in American Football

A Review Paper

Melissa N. Womble, PhD, and Michael W. Collins, PhD

across time and occurrence of concussions during most life activities. Although it is reasonable for Abstract concerns to be presented, it is important to better Major advancements in sport-related understand SRC and the current factors leading to concussion (SRC) management have prolonged recoveries, increased risk for injury, and been made across time to improve potentially long-term effects. the safety of contact sports, including football. Nevertheless, these advances What Is a Concussion? are often overlooked due to concerns Concussions occur after sustaining direct or regarding the potential long-term effects indirect injury to the head or other parts of the of SRC. Although further research is body, as long as the injury force is transmitted needed, it is critical that current efforts are to the head. Athletes often experience physical, focused on better understanding SRC in cognitive, emotional, and sleep-related symp- order to recognize and change ongoing toms post-concussion secondary to an “energy factors leading to prolonged recoveries, crisis” within the brain.2 The energy crisis occurs increased risk for injury, and potentially as the result of transient neurological dysfunction long-term effects. To reduce risk for these triggered by changes in the brain (eg, release of outcomes, future focus must be placed on neurotransmitters, impaired axonal function).2,3 increased education efforts, immediate Concussion is undetectable with traditional reporting of injury, prevention techniques, imaging; however, advanced imaging techniques targeted treatment, and the development (eg, diffuse tensor imaging) have shown progress of multidisciplinary treatment teams in assessing axonal injury.3 Symptom duration nationwide. Finally, with the progress in post-concussion is highly variable due to individual understanding concussion, it is important differences; a recent study showed recovery took to remain vigilant of additional advances 3 to 4 weeks for memory and symptoms.4,5 that will help to further improve the safety of contact sports, including football. Previous Concussion Management Identification techniques and return-to-play guidelines for concussion have significantly changed ootball is an important component of across time. In the past, concussion grading scales American culture, with approximately 3 were utilized for diagnosis and return to play was F million youth athletes, 1.1 million high school possible within the same contest.6,7 It has since athletes, and 100,000 college athletes participat- been recognized that initial concussion severity ing each year.1 Participation in football provides makes it difficult to predict recovery.3 For example, athletes with physical, social, psychological, research revealed memory decline and increased and academic benefits. Despite these benefits, symptoms 36 hours post-injury for athletes with widespread focus has been placed on the safety a grade 1 concussion (ie, transient confusion, no of football due to the risk for sport-related con- loss of consciousness, concussion symptoms cussion (SRC) and potentially long-term effects; or mental status changes that resolve within 15 however, little recognition has been given to minutes of injury) compared to baseline.7 Another the advancements in concussion management study found duration of mental status changes

Authors’ Disclosure Statement: Dr. Collins is a cofounder of ImPACT Applications, Inc. However, the ImPACT test is not the focus of this article. The authors report no actual or potential conflict of interest in relation to this article.

352 The American Journal of Orthopedics ® September/October 2016 www.amjorthopedics.com to be related to slower symptom resolution and Observation memory impairment 36 hours to 7 days post-inju- On the sideline, it is important to identify any im- ry.6 Consequently, return to play within the same mediate signs of injury (ie, loss of consciousness, contest was likely too liberal. Guidelines today anterograde/retrograde amnesia, and disorienta- recommend immediate removal from play with tion/confusion). Since immediate signs are not suspected SRC. Nevertheless, the “play through always present, it is important to be aware of the pain” culture has led athletes to continue playing most commonly reported symptoms, including after SRC, contributing to prolonged recoveries and headache, difficulty concentrating, fatigue, drows- potentially long-term effects. iness, and dizziness.13 If symptoms are not reported by the athlete, balance problems, Current Concussion Management: Continued lack of coordination, increased emo- Concerns and Areas of Improvement tionality, and difficulty following Despite increased awareness of concussions, instructions may be observed recent estimates revealed high rates (ie, 27:1 ratio during play.12 for general players) of underreporting in college football, particularly amongst offensive linemen.8 On-Field Assessment Researchers have studied recovery implications for Cognitive and balance remaining in play, with one study revealing a 2.2 testing are essential times greater risk for prolonged recovery in college in determining if an athletes with delayed vs immediate removal.9 athlete has sustained a Another similar study discovered an 8.8 times concussion. Immediate greater risk for prolonged recovery in adolescent declines in memory, and young adult athletes not removed vs removed concentration abilities, from play.10 Further analysis found remaining in and balance abilities are play to be the greatest risk factor for prolonged common. Given limita- recovery compared to other previously studied risk tions in administering long factors (eg, age, sex, posttraumatic migraine).10 testing batteries on the Additionally, significant differences in neurocogni- sideline, brief standardized tive data were seen between the “removed” and tests such as the Standardized “not removed” groups for verbal memory, visual Assessment of Concussion (SAC), memory, processing speed, and reaction time Balance Error Scoring System (BESS), at 1 to 7 days and 8 to 30 days.10 The recovery and Sport Concussion Assessment Tool implications of remaining in play and the additional (SCAT) are commonly utilized. Identification of risk for second impact syndrome (SIS), or repeat cognitive and/or balance abnormalities can help the concussion when recovering from another injury, athlete recognize deficits following injury.12 Balance emphasizes the need for further education efforts problems are experienced due to abnormalities in amongst athletes to encourage immediate report- sensory organization and generally resolve during ing of injury.11 the acute recovery period.14,15 Cognitive difficulties typically persist longer than balance problems, Sideline Assessment though duration varies widely. Sideline assessment has become a vital component of concussion management to rule out Neurologic Evaluation concussion and/or significant injury other than con- A neurologic evaluation including cranial nerve cussion. Assessment should include observation, testing and evaluation of motor-sensory function cognitive/balance testing, neurologic examination, (ie, assessment for the strength and sensation of and possible exertion testing to ensure a compre- upper and lower extremities) is important to identi- hensive evaluation of all areas of potential dys- fy focal deficits (ie, sensation changes, loss of fine function.12 Indications for emergency department motor control) indicative of serious intracranial pa- evaluation include suspicion for cervical spine thology.12 Additionally, clinicians have suggested in- injury, intracranial hemorrhage, or skull fracture as clusion of vestibular and oculomotor assessments well as prolonged loss of consciousness, high- due to frequent dysfunction post-concussion.12,15,16 risk mechanisms, posttraumatic seizure(s), and/or Examination of the vestibular/oculomotor sys- significant worsening of symptoms.12 tems through tools such as the Vestibular/Ocular www.amjorthopedics.com September/October 2016 The American Journal of Orthopedics ® 353 Concussions in Football

Motor Screening (VOMS) assessment (assesses tolerance of physical exertion, balance functioning, both the vestibular and oculomotor systems) and and cervical spine integrity (if necessary).29,30 Due King-Devick Test (primarily assesses saccadic eye to individual differences and the heterogeneous movements) can elicit symptoms that may not symptom profiles, concussion management must present immediately. If assessment appears nor- move beyond a “one size fits all” approach to avoid mal, exertion testing can be utilized to determine if nonspecific treatment strategies and consequently symptoms are provoked through physical exercise prolonged recoveries.29 Clinicians and researchers at that should include cardio, dynamic, and sport-spe- University of Pittsburgh Medical Center have identi- cific activities to stress the vestibular system.12 fied 6 concussion clinical profiles (ie, vestibular, -oc ular, posttraumatic migraine, cervical, anxiety/mood, Risk Factors for Injury and Prolonged Recovery and cognitive/fatigue) that are generally identifiable Medical professionals must consider the presence 48 hours after injury.29,30 Identification of the clinical of risk factors when managing concussion in order profile(s) through a comprehensive evaluation to make appropriate treatment recommendations guides the development of individualized treatment and return-to-play decisions. Research has demon- plans and targeted rehabilitation strategies.29,30 strated the role of female gender, learning disability, Vestibular. The vestibular system is responsible attention-deficit/hyperactivity disorder, psychiatric for stabilizing vision while the head moves and history, young age, motion sickness, sleep problems, balance control.15 Athletes can experience central somatization, concussion history, on-field dizziness, and/or peripheral vestibular dysfunction to include posttraumatic migraine, and fogginess in increased benign paroxysmal positional vertigo (BPPV), risk for injury and/or prolonged recovery.17-25 Addition- visual motion sensitivity, vestibular ocular reflex ally, athletes with ongoing symptoms from a previ- impairment, and balance impairment.30,31 Symp- ous injury are at risk for sustaining another injury. toms typically include dizziness, impaired balance, blurry vision, difficulty focusing, and environmental Acute Home Concussion Management sensitivity.15,29,30 Potential treatment options include Although strict rest has been recommended vestibular rehabilitation, exertion therapy, and post-concussion, recent research evaluating strict school/work accommodations. rest vs usual care for adolescents revealed greater Ocular. The oculomotor system is responsible for symptom reports and longer recovery periods for control of eye movements. Athletes can experi- the strict rest group.26 Based on these findings ence many different posttraumatic vision changes, and emphasis for regulation within the migraine including convergence problems, eye-tracking literature (due to the common pathophysiology be- difficulties, refractive error, difficulty with pursuits/ tween migraine and concussion27), we recommend saccades, and accommodation insufficiency. that athletes follow a regulated daily schedule Symptoms typically include light sensitivity, post-concussion including: 1) regular sleep-wake blurred vision, double vision, headaches, fatigue, schedule with avoidance of naps, 2) regular meals, and memory difficulties.15,29,30 Potential treatment 3) adequate fluid hydration, 4) light noncontact options include vision therapy, vestibular rehabilita- physical activity (ie, walking, with progressions tion, and school/work accommodations.32 recommended by a physician), and 5) stress man- Posttraumatic Migraine. Headache, the most agement techniques. Use of these strategies im- common post-concussion symptom, can persist mediately can help in preventing against increased and meet criteria for posttraumatic migraine (ie, uni- symptoms and stress, and decreases the need for lateral headache with accompanying nausea and/ medication in select cases. Additionally, over-the- or photophobia and phonophobia).29,30,33 Implemen- counter medications should be limited to 2 to 3 tation of a routine schedule, daily physical activity, doses per week to avoid rebound headaches.28 exertion therapy, pharmacologic intervention, and school/work accommodations are potential treat- In-Office Concussion Management ment options. Athletes diagnosed with SRC will experience differ- Cervical. The cervical spine can be injured during ent symptoms based on the injury mechanism, risk whiplash-type injuries. Therefore, determining factors, and management approach. Comprehen- the location, onset, and typical exacerbations of sive evaluation should include assessment of risk pain can be helpful in identifying cervical involve- factors, injury details, symptoms, neurocognitive ment.29,30 Symptoms typically include headaches, functioning, vestibular/oculomotor dysfunction, neck pain, numbness, and tingling. Evaluation and

354 The American Journal of Orthopedics ® September/October 2016 www.amjorthopedics.com M. N. Womble and M. W. Collins

therapy by a certified physical therapist and phar- ing and fear of reporting in athletes. macologic intervention (eg, muscle relaxants) are Prevention techniques: Athletes must be taught potential treatment options. 29,30 proper form and playing techniques to reduce the Anxiety/Mood. Anxiety, or worry and fear about risk for concussion. Proper form and technique everyday situations, is common post-concussion should be incentivized. and can sometimes be related to ongoing vestib- Targeted treatment: Individualized treatment plans ular impairment. Symptoms typically include rumi- and targeted rehabilitation strategies must be native thoughts, avoidance of specific situations, developed based on the identified clinical profile(s) hypervigilance, feelings of being overwhelmed, to avoid nonspecific treatment recommendations. and difficulty falling asleep.29,30 Potential treatment Multidisciplinary treatment teams: Given the het- options include implementation of a routine sched- erogeneous symptoms profiles and need for care ule, exposure to provocative situations, psycho- provided by different medical specialties, multidis- therapy, pharmacologic intervention, and school/ ciplinary teams are essential. work accommodations.34 Remain current: With the progress in understand- Cognitive/Fatigue. A global concussion factor (in- ing concussion, providers must remain vigilant of cluding cognitive, fatigue, and migraine symptoms) future advances in concussion management to has been identified within 1 to 7 days of injury. Al- further improve the safety of football. though this factor of symptoms generally resolves during the acute recovery period, it persists in select cases.13 Symptoms typically include fatigue, Dr. Womble is Director, Inova Sports Medicine Con- decreased energy levels, nonspecific headaches, cussion Program, Inova Medical Group, Department potential sleep disruption, increased symptoms of Orthopaedics and Sports Medicine, Fairfax, Virginia. Dr. Collins is Director, University of Pittsburgh Medical towards the end of the day, difficulty concentrating, Center Sports Medicine Concussion Program, Univer- and increased headache with cognitive activi- sity of Pittsburgh, Department of Orthopaedic Surgery, ties.29,30,35 Routine schedule, daily physical activity, Pittsburgh, Pennsylvania. exertion therapy, pharmacologic intervention (eg, Address correspondence to: Melissa N. Womble, PhD, amantadine), and school/work accommodations are Inova Medical Group Orthopaedics and Sports Medicine, potential treatment options.30 8501 Arlington Boulevard, Suite 200, Fairfax, VA 22031 (tel, 703-970-6464; fax, 703-970-6466; email, me- Conclusion [email protected]). Advancements in SRC management warrant Am J Orthop. 2016;45(6):352-356. Copyright Frontline change in the conversations regarding concus- Medical Communications Inc. 2016. All rights reserved. sion in football. Specifically, conversations should References address the current understanding of concussion 1. Dompier TP, Kerr ZY, Marshall SW, et al. Incidence of and improvements in the safety of football through concussion during practice and games in youth, high school, stricter concussion guidelines, detailed sideline and collegiate American football players. JAMA Pediatrics. 2015;169(7):659-665. evaluations, recognition of risk factors, improved 2. Giza C, Hovda D. 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Erratum In the Editorial Board Biographies in the May/June issue (Am J Orthop. 2016;45(4):198), Associate Editor Jose B. Toro, MD, was incorrectly listed as director for orthopedic traumatology at Cohen Children’s Medical Center Hospital. Dr. Toro does not hold that position.

356 The American Journal of Orthopedics ® September/October 2016 www.amjorthopedics.com