A star wide receiver crosses the field and makes a leaping catch late in the game against his high school’s biggest rival. Before his feet hit the ground, the opposing free safety, running full speed, crushes him. The force of the defender’s shoulder hitting his chest snaps his head back. Now he’s lying flat on his back, motionless. Athletic trainers rush to his aid and help him to his feet. While noticeably groggy, he manages to slowly walk off the field.
Now the team doctor and athletic trainer must quickly decide whether the injured player suffered a concussion.
Doctors and athletic trainers need sideline assessment tools we can administer quickly. Those tests must correctly identify a player who has truly suffered a concussion while also ruling out a player who did not.
Two new tests might help sports medicine professionals quickly and more accurately identify athletes who suffered concussions.
Current sideline concussion assessment
Currently an athletic trainer or doctor asks a player about headaches and other symptoms. He then administers a standard battery of tests on the sidelines. The examiner asks the player to remember a series of words and repeat them right away and again a few minutes later. He asks the athlete to count numbers backwards or name the months backwards. He tests the athlete’s balance through single- or double-leg stance with his eyes closed. He tests coordination with quick finger-to-nose movements.
While this evaluation correctly identifies a large portion of athletes who suffer mild traumatic brain injuries, it might not catch them all. Not all concussions present with the same symptoms or affect athletes in the same way.
Visual problems and dizziness
Half of concussed athletes have dizziness as one of their presenting symptoms. The current sideline tests poorly assess the vestibular system impaired in athletes with dizziness. Since the presence of dizziness makes an athlete 6.4 times more likely to have a prolonged recovery (longer than 21 days), it’s important that we identify it in our initial exams.
Likewise, 30% of athletes report visual problems like blurred or double vision, difficulty reading or problems visually concentrating. Yet the standard sideline tests do not adequately assess eye motor function.
The K-D test and VOMS assessment
In recent weeks, studies have shown the effectiveness of two new assessments – the King-Devick (K-D) test and the Vestibular/Ocular Motor Screening (VOMS) assessment – in identifying concussions as part of a comprehensive sideline evaluation.
The K-D test requires injured athletes to quickly read and name numbers from left to right on three test cards or an iPad. The longer it takes an athlete to name all of the numbers, the worse his test score. Performed in addition to the other concussion exams, the K-D test offers additional information on vision and rapid eye movements.
The VOMS assessment judges both vision and the vestibular system. The examiner tests the athlete’s ability to visually follow a moving target, his ability to switch between looking at two different objects, and his ability to view an object moving closer to him without getting double vision. The athletic trainer or doctor also determines if these tests cause the athlete to experience symptoms.
Potential to help clinicians evaluate and treat concussed athletes
These tools can hopefully soon help doctors and athletic trainers in a few ways. They can help us identify athletes with predominantly ocular or vestibular impairments, like dizziness and blurred vision, that are currently difficult to identify. Adding a few minutes to the evaluation process might be worthwhile if it keeps a young concussed athlete off the field.
These tests might also help identify players hiding or denying symptoms. Several NFL players have admitted to denying concussion symptoms to the medical staffs. In an anonymous survey of college athletes with a concussion history, 43% admitted that they have hidden their symptoms to stay in a game, and almost one quarter said they would do so in the future. If an athlete denies having any symptoms, including dizziness or blurred vision, these tests would detect his impairments. Doctors could confidently hold him out of the game.
Hopefully these types of tests and others will soon help a clinician provide individualized treatments for the previously mentioned wide receiver, such as vestibular therapy for dizziness or visual rehab for ocular motor dysfunction. Right now, we need these tests to help us keep him off the field and protect him from a more serious brain injury.
Note: A modified version of this post appears as my sports medicine column in the August 21, 2014 issue of The Post and Courier.
Anne Mucha, Michael W. Collins, R.J. Elbin, Joseph M. Furman, Cara Troutman-Enseki, Ryan M. DeWolf, Greg Marchetti, and Anthony P. Kontos. A Brief Vestibular/Ocular Motor Screening (VOMS) Assessment to Evaluate Concussions: Preliminary Findings. American Journal of Sports Medicine. Published online before print August 8, 2014.
Zoe Marinides, Kristin M. Galetta, Connie N. Andrews, James A. Wilson, Daniel C. Herman, Christopher D. Robinson, Michael S. Smith, Brett C. Bentley, Steven L. Galetta, Laura J. Balcer, and James R. Clugston. Vision testing is additive to the sideline assessment of sports-related concussion. Neurology Clinical Practice. Published online ahead of print July 9, 2014.
Daniel M. Torres, MD, Kristin M. Galetta, MS, H. Westley Phillips, BS, E. Mark S. Dziemianowicz, BS, James A. Wilson, BA, Emily S. Dorman, MEd, ACT, Eric Laudano, ACT, Steven L. Galetta, MD, and Laura J. Balcer, MD, MSCE. Sports-related concussion: Anonymous survey of a collegiate cohort. Neurology Clinical Practice. Aug 2013; 3(4): 279–287.