Concussion - Your Game Plan for Recovery (eBook)

Chapter 4

Sideline Assessment of Concussion

Over 8 million middle school, high school and college students are involved in sports. A significant percentage of these students play contact sports. The CDC estimates that up to 3.8 million sports-related concussions occur annually, and many of these go undetected. Identifying a concussion on the sidelines is challenging for a number of reasons. During a game, there may be limited time to properly evaluate a potentially injured athlete. Moreover, high school and college athletes often underreport symptoms to remain in the game. A 2004 survey of high school football players revealed that over 40% of athletes underreported concussion symptoms (McCrea et al. 2004). In spite of significant educational efforts to inform student athletes about the risk of concussion, data obtained 10 years later show that many athletes continue to downplay symptoms to obtain clearance to play sports (Meier et al. 2015).

Missed concussion diagnoses can have serious health implications. Athletes who play through a concussion have an 8.8-fold likelihood of having a prolonged recovery time (Elbin et al. 2016). Athletes who play with a concussion are at higher risk for secondary orthopedic injuries, likely due to decreased coordination and slower reaction times (Herman et al. 2017). Finally, concussed athletes who are not removed from play are at risk of second impact syndrome.

Second impact syndrome was first described in 1984 and is defined by two occurrences. First, an athlete sustains an initial concussion. He or she then sustains a second head injury (either through direct or indirect impact) before having time to recover from the first injury. The second injury triggers significant brain swelling. This brain swelling can result in high enough pressure in the skull to cause brain herniation. The resulting herniation of the brain stem can lead to severe disability or death. Second impact syndrome is thankfully a rare event, but nonetheless devastating. It is the reason behind the creation of the Zachary Lystedt law and the nationwide call to remove from play athletes with a suspected concussion.

Zachary Lystedt was 13 years old at the time of his injury in 2006. His head struck the ground during a football game. He sat out the next three plays and then returned to the field. A second injury caused Zachary to collapse to the ground. He was airlifted to Harborview Medical Center in Washington State, where he underwent emergency neurosurgery. Zachary is lucky to still be alive today but suffers from severe neurologic complications from his injury. His parents are the catalyst behind the Zachary Lystedt law, passed in 2009, which mandated that players are evaluated and removed from play if they have a suspected concussion. Since 1980, estimated cases of second impact syndrome have ranged from 35 to 94 in total (Cantu and Gean 2010). Until now, the published medical literature indicates that patients affected by second impact syndrome have all been male adolescent or young adult football players.

The mechanism of how second impact syndrome occurs is unclear; however, it is believed to be related to a disruption in the brain’s ability to regulate blood flow after injury. The second brain injury causes an increase in blood flow to the brain, leading to brain swelling and herniation.

The question of when you are clear from the risk of second impact syndrome does not have a definite answer. Lag times between concussions that result in second impact syndrome range from 1 hour to 4 weeks, making it difficult to say when an athlete is in the clear from experiencing a catastrophic second impact (McLendon et al. 2016).

Objectives of Sideline Assessment

A sideline assessment is performed by a medical provider, athletic trainer, coach or, sometimes, a parent volunteer. The purpose of the assessment is to determine whether it is safe for an athlete to return to play after an injury. If an athlete is down on the field, the first priority is to assess whether the athlete has suffered a life-threatening injury and needs immediate stabilization and transport to the nearest emergency department. The first priority is to evaluate the ABCDs – airway, breathing, circulation and disability (spinal cord injury). Evaluation of the ABCDs includes the following questions:

1. Is the athlete breathing?

2. Does the athlete have a pulse?

3. Does the athlete have a significant injury with possible internal or external bleeding?

4. Is the athlete alert or, if not alert, arousable?

5. Does the athlete have any pain along the cervical spine (back of the neck)?

6. Does the athlete have any loss of sensation or weakness in his or her arms or legs?

7. While you are observing the athlete, is he or she vomiting? Is their state of awareness decreasing?

8. Signs of a serious brain injury might include clear fluid drainage from the nose or ears, altered or worsening mental status or unequal pupils.

If the answer is yes to any of these questions, or the athlete shows any of the above signs, follow basic life support protocol and call 911 for transfer to the closest emergency department.

Only experienced medical providers should remove the athlete’s helmet if they are wearing one. If the athlete is unresponsive, one should assume that there may be spinal cord injury, and the athlete should not be moved without spinal stabilization. Emergency stabilization before concussion assessment was not spelled out until the most recent version of the Sport Concussion Assessment Tool, the SCAT 5. Until 2018, the Sport Concussion Assessment Tool focused primarily on concussion evaluation. The SCAT 5 is the first sideline assessment test that emphasizes emergency assessment and stabilization first.

SCAT

While tremendous progress has been made in the field of concussion diagnosis and treatment, there is still no gold standard test for concussion diagnosis; however, there are certain signs and symptoms that are consistent with concussion. In 2004, experts in the field of concussion management convened as the Concussion Group in Sports to design a multimodal tool that can be used to assess an athlete for concussion on the sidelines (McCrory et al. 2005). The objective of this tool, called the Sport Concussion Assessment Tool, was initially to help medical providers decide whether an athlete has sustained a concussion and should be removed from play. It has since evolved to include cervical spine injury assessment and evaluation for more serious traumatic brain injury. The tool has undergone a series of revisions since its inception in 1998. The first version was the SAC (Standardized Assessment of Concussion), followed by the SCAT, SCAT 2, SCAT 3 and SCAT 5. The SCAT 3 and the SCAT 5 have accompanying pediatric versions that can be applied to athletes aged 5–12: Child SCAT 3 and Child SCAT 5 (McCrory et al. 2009, Guskiewicz et al. 2013, Echemendia et al. 2017).

Cognitive Assessment

Two parts of the SCAT evaluate cognitive functioning: the SAC and the Maddocks score. The SAC evaluates an athlete’s cognitive status and focuses on orientation, immediate verbal memory, delayed verbal memory and concentration. Concentration is assessed by asking the athlete to repeat a series of numbers in reverse order. When appropriate, the SAC also includes exertional maneuvers such as sit-ups and jumping jacks to determine whether physical exertion will elicit concussion symptoms. The SAC has a sensitivity ranging from 80% to 94% and a specificity ranging from 76% to 91% (Barr and McCrea 2001). In other words, 20% of patients with concussion could be missed and 25% of athletes without a concussion will be diagnosed with a concussion. To dust off some cobwebs, sensitivity is the true positive rate, and specificity is the true negative rate. Sensitivity is useful when it’s very important not to miss anyone with a disease. High specificity is important when you don’t want to falsely diagnose someone with a disease. In the case of concussion, having both high sensitivity and specificity are obviously important. The current SAC test is shown in Figure 5.

Figure 5. The Current Standardized Assessment of Concussion (SAC)

Reproduced from the SCAT 5
(Sport concussion assessment tool - 5th edition
British Journal of Sports Medicine 2017)

Immediate and delayed verbal memory is assessed by having the athlete repeat 5 or 10 words during the SAC and then again after the SAC is completed. Concentration or processing is assessed by asking the athlete to repeat a string of numbers or the months of the year in reverse order. For example, if the athlete is given the numbers 1,2,3, he repeats 3,2,1.

Concussed athletes may present with disorientation to time and place. The SAC assesses orientation to date, time and place, but these questions have been found to be less sensitive than the Maddocks score, which is specific to sports-related concussion. The Maddocks questions include:

1. Where are we playing today?

2. Which half is it now? (or period, depending on the sport)

3. Who scored last?

4. What team did you play last week (game)?

5. Did your team win the...