Baseline testing– Is this the answer to CONCUSSION care we are looking for?

Concern about concussion in the community is growing and people are asking important questions about how to improve concussion care and long-term brain health. The answer to these questions may well be already underway with improved clinical assessments. Improving concussion assessments may be the solution to many of the concerns that currently plague current practice. Improved assessments lead to informed choices and ultimately better care. Simple right? Well, yes, but we have some work to do. The good news is, we can start implementing better concussion assessments now! How do we do this?

Let us start with what is known about concussion assessments.

Assessment seems to fall into 2 categories.

1.  Assessment to confirm a concussion has occurred, and,
2.  Assessment to provide valuable information to guide best treatment and care following concussion.

The distinction between these 2 categories is very important before we delve further into the scientific evidence. Plenty of research has continued to investigate objective measures that help confirm a brain injury has occurred, while at the same time, research has also been providing evidence about what treatments and interventions are most beneficial for recovery. So, when we investigate various types of assessments, we often find information about sensitivity (test that correctly identifies who has concussion), specificity (identifies those who do not), as well signs and symptoms that may help predict prolonged recovery and persistent symptoms. In practice however we are also looking to assess each individual carefully to determine what types of clinical care they need.

Despite its importance, concussion assessments have historically had limitations. The challenge has been in trying to capture the many varied signs and symptom of acute traumatic brain injury, identifying it’s overlay with other injuries (such as cervical whiplash) and recognising co-existence with pre-existing conditions (such as migraine) that influence signs, symptoms, and recovery.

Best practice guidelines recommend that concussion assessments should be ‘multimodal’ – that test a number of different types of brain function (1). The fifth version of the Sport Concussion Assessment Tool – SCAT5 & Child SCAT5 uses a brief test of observations, cognitive testing, cervical spine assessment, symptom evaluation, coordination, and balance testing. At a basic level this 15-20 minute assessment provides a useful screen to guide clinical decision making (2). However, it is still just a simple screen.

“a reliance on symptom reporting has obvious limitations.”

Symptoms evaluation following concussion remains a very important part of the concussion assessment process and seeks to determine symptoms such as dizziness, headaches, balance, anxiety, sleep, neck pain, memory, concentration, and many others. There are many symptoms questionnaires used in practice (3) including the Post Concussion Symptom Scale (also used within the SCAT5). Research continues to support symptom reporting as vital component of concussion assessment. However, a reliance on symptom reporting has obvious limitations. Symptoms are subjective and rely on the perception and interpretation of the person injured, and whether they choose to disclose all their symptoms. Non-disclosure remains a major challenge in sport, which can lead to athlete playing on with concussion or returning too early. This is known to worsen outcomes, even over the longer term (4). A recent survey of nearly 2,000 high school students revealed that 22% of students did not even report their concussion to an adult (5). Many people are surprised that early and honest disclosure leads to favourable outcomes with an earlier return to play, a message that should be priority for community awareness campaigns. On the flip side, over emphasis on symptoms for some can lead to hypervigilance, anxiety and can become detrimental to practice self-management, particularly if symptoms become chronic. Symptoms therefore need to be supported with additional objective tests. Many objective measures have emerged to provide additional information about brain function after concussion. These include.

Vestibular Ocular Assessments

The Vestibular Ocular Motor Scale (VOMS) (6–8) provides a stepwise guide of well-known bedside vestibular-ocular clinical assessment that screens smooth pursuit, saccades, gaze stability, convergence and motion sensitivity , and includes a value to determine how much these tests provoke an increase in symptoms. VOMS has proven to be not only a sensitive test, but it is also clinically useful in determining who needs further testing of vestibular function and/or visual function, particular ocular movement and binocular vision (9,10). Another test of saccadic eye movements is the King-Devick test, which has also been used in concussion assessments (11,12). Emerging eye tracking technology is also allowing much more objective data of vestibular-ocular movements to be included in clinical assessments (13,14).

Balance

Standing Balance remains another key measure (15,16). In clinic or sporting clubs, the modified Balance Error Scoring System (mBESS) has proven to be a sensitive screen which has also been included into the SCAT5. (17,18). Gait, especially tandem gait has also been a useful assessment tool (19).

Cervical spine

Neck injury and whiplash should belong to the concussion discussion, due to it’s key role in signs and symptoms relating to the sensorimotor control of balance and vision, and symptoms of headache, dizziness and neck pain/stiffness. The cervical spine can be assessed in terms of range and strength/endurance as well as proprioceptive awareness and influence on smooth pursuit eye movements (20). Cervical strength, stability and anticipatory postural control may be a promising target to reduce risk of further concussions (21).

Cognition

Neuro Cognitive Tests were trialled over the past decade (22), especially computerised screening of brain functions such as attention, concentration, memory, executive function, visuospatial skills and processing speed to help confirm concussion when compared to baselines testing or normative scores (23). Despite limited evidence for the usefulness of these tests used in isolation it is astounding (and disappointing) they continue to be used in favour of other brain functions (24). Clinically Neuro cognitive tests remain challenged by their time, costs and limited access of health professionals who are trained in psychometric testing who might interpret the results appropriately. Processing speed via reaction time tests however is a simple option that is quick and easy while still provide quick and sensitive data to confirm concussion. Will this be an alternative to some longer neuro cognitive screens? It will be interesting to see how these tests evolve with evidence (25).

Mental health

Psychological changes after concussion is common including agitation, aggression, emotional, anxiety, depression and post-traumatic stress. Declining mental health after concussion is a major concern, with increased risk of depression, anxiety and suicide risk (26,27). Mental health is therefore an automatic priority inclusion into the concussion assessment.

Autonomic functions

Autonomic dysfunction is common and includes changes to heart rate regulation, blood pressure and body temperature control, all of which often contribute to worsening of symptoms with aerobic exercise, which forms the basis of clinical testing after concussion and has proven to be an target for improved recovery (28,29).

Sleep

Sleep is also a huge issue, with problems with too much sleep as well as insomnia after concussion. Sleep has also been associated with persistent symptoms following concussion (30) Sleep can be monitored with questionnaires and is included in previously mentioned symptoms screens.

“To date all these developments have not yet reached clinical practice far outside the realms of laboratory research. However, watch this space!”

Imaging/Biomarkers/genetic testing and neurophysiological measures

Other tests include medical Imaging  such as CT and MRI to be used to identify haemorrhages, microhaemorrhages or other structural injury that may be suspected (31). Biomarkers in blood or saliva (32,33) are also emerging, in addition to genetic testing. Transcranial Magnetic Stimulation is another investigative tool that has detected dysfunction in central information processing that may link to a number of concussion signs and symptoms.  (34) To date all these developments have not yet reached clinical practice far outside the realms of laboratory research. However, watch this space!

For clinical assessment, it is clear that assessment is only useful if it is ‘Multimodal’ and includes symptoms, balance, vestibular-ocular, cognition, sleep, autonomic dysfunction and mental health. Meanwhile, evidence has also been building in relation to optimal treatment & care for people following concussion. Treatments that focus on autonomic dysfunction – aerobic exercise tolerance (29,35), sleep, vestibular, cervical , ocular treatment in physiotherapy (36) and treatments for vision, sleep, anxiety and depression are vital (37). This means assessment needs to include these domains to ensure appropriate referral and access to early individualised treatments.

Baseline testing at North Adelaide Football Club with Your Brain Health

So where does Baseline testing fit in?

Within all the domains of assessment mentioned so far, there is enough individual variation to make interpretation of assessment difficult at times, especially as we try and determine the main drivers of persistent symptoms. Establishing a pre-injury baseline of an individual’s symptoms and objective signs relevant to concussion helps provide a reference point to improve interpretation of each test. Baseline testing improves concussion assessments for both categories of assessment.

1.  It improves assessments post injury to confirm concussion (38).
2.  Improves assessments to help guide treatments.

“A pathway is needed for referrals to appropriate health professionals.”

If baseline testing is to be a viable option in the real world, we feel it needs to meet a number of prerequisites.

• It needs to be multimodal as much as possible.
• Tests need to valid and reliable.
• As a screen, it needs to be efficient. Long detailed assessments become less attractive and cost effective for sporting organisations & schools. Even when we are dealing with brain health! Baseline screens need to be quick! Longer detailed assessments can then be undertaken with a referral on to specialist services to be managed at an individual level.
• It needs to be safe, usable, and acceptable for use within a club/school environment, with equipment that is portable & affordable. Research tests using Transcranial Magnetic Stimulation, Force plates to measure sway in standing balance, and detailed neuropsychology tests are just not suitable as a screen. These tests can be important, don’t get me wrong, but are more suited to detailed assessment following effective referral pathways.
• Any data collected needs to be secure, but accessible to relevant clinicians who can interpret the results appropriately & in the context of the individual. A pathway is needed for referrals to appropriate health professionals. There is no use collecting data that cannot be appropriately assessed in the context of all other tests results. Poor interpretation can lead to missed diagnosis, missed referrals, as well as inappropriate referrals, unnecessary investigations, and over-servicing. All of these lead to less favourable outcomes.
• It needs to be offered to at risk populations. This is the logistical challenge. Concussions occurs frequently in schools, both in the playground and on the sporting field. Plenty of sports experience concussions and even sub-concussion head knocks such as rugby, Australian rules football, gridiron football, soccer, cricket, skiing, basketball, gymnastics, lacrosse, race cars, netball…and the list goes on. It is anticipated that baseline screening of brain health will become a standard part of these sports. Baseline musculoskeletal screening to help reduce injury risk is already common practice as well as load management, mouth guard or helmet fittings, sleep, and wellness tracking. Now, finally, brain health can be included as well!

If these prerequisites are met, baseline testing is a feasible and valuable way of improving concussion assessment and management. So why is there still some reluctance?

Previous experience with some baseline testing of only select functions such as some computerised neuro cognitive testing (not multimodal) have proven disappointing - both in terms of feasibility, time, cost in addition to limited clinical evidence (22).

Guidelines have also been historically reluctant to recommend compulsory baselines testing at all levels. There may be a few reasons for this.

• The general public may misinterpret its role and may think post-concussion assessments are not effective without a previous baseline. This may result in people not seeking the appropriate follow-up advice in the event of a concussion. As we have already mentioned, disclosure of symptoms is already a huge problem. People may also think baseline tests will provide objective data that threatens their work or sporting career.
• In addition, health professionals may be concerned about over-testing, and uncovering a complex issue that their health service is unable to deal with adequately. Litigation in concussion, in relation to long term brain health is making many health professionals nervous.
• Depending on the type, baseline testing costs money & time. This raises questions about inequity and health. How many people would miss the most effective concussion assessments?

In the search for improved standards, baseline testing is definitely on it’s way into clinical practice, and is being included into guidelines, such the current Australian Football League Guidelines.

What is the solution? From our vantage point, the solution is already emerging. The requirements are becoming clear. We need to use best evidence to provide multidimensional baseline tests that are efficient, effective, and inexpensive. Use tests that cover domains commonly affected by concussion/TBI. Screen these domains quickly, with enough information to use as a comparison with identical post injury assessments.

“This type of technology allows for screening in clinic or at sporting facilities with detailed measures previously only available at more specialised research facilities.”

Include a history, especially information about previous concussions & migraine, but also learning disorders, neck injuries and mental health. Symptoms reporting remains vitally important and can be screened quickly. Standing balance can be measured quickly and Neuro Cognitive tests or quick tests of reaction time can also be included.

Vestibular ocular motor assessment has emerged as priority measure. The advantage of Vestibular ocular assessment screens is that it quickly assesses multiple different brain networks and has proven to be a sensitive measure (9) with implications for informing some of the best evidence based concussion treatments (36). More recently, even more sensitive virtual reality eye tracking devices such as NeuroFlex® are enabling clinicians to collected detailed objective information about vestibular ocular reflex, smooth pursuit movement in both head free and fixed positions (including vergence), saccadic eye movements, anti-saccades (cognitive test), nystagmus and optokinetic nystagmus all within minutes! This type of technology allows for screening in clinic or at sporting facilities with detailed measures previously only available at more specialised research facilities. Software also allows for direct comparison with baseline tests and can be used to track brain health performance over the long term.

Remember, baseline testing is still just a ‘screen’, and can lead to further detail and gold standard investigations with appropriate referrals e.g., vestibular investigations with Vestibular Physiotherapists or Neurotology, ocular tests with orthoptists and neuro-ophthalmologists, neuro cognitive testing with neuropsychologists, sleep investigations with sleep specialists, cervical investigation with neurosurgery/orthopaedics and physiotherapists.

“This means that baseline testing is more than the sum of its parts.”

Our own practice-based experience has taught us that baseline screening provides additional benefits that are worth considering.

It provides an opportunity for education about concussion to everyone, to create an awareness of signs and symptoms to help recognise concussion and outline the ‘end-to-end’ management of concussion pathway that stems from multimodal concussion assessments. This education is provided at a moment in time when there is less stress, anxiety or urgency that may occur following concussion.

Tracking brain health over time helps manage many areas beyond the scope of a single concussion. You potentially can start to detect the cumulative effect of multiple     concussions. Sleep, mental health, migraines, headaches, neck strength and stability, balance and vision can all benefit from optimal care, and baseline screening has a role in identifying and directing best care for these issues.

We have discovered that baseline testing is an important part of the end-to-end management of concussion. It not only helps confirm a diagnosis concussion, but more importantly helps guide the best available clinical interventions and provides opportunity for education about brain health beyond the scope of just concussion. This means that baseline testing is more than the sum of its parts. Baseline testing has evolved, and the next step is to ensure implementation into practice does not take over 17 years which can often be the case when translating research into practice! (39) Good education is essential for both community and health professionals. Technology is moving fast, with the potential to enhance known the evidence and improve assessments. Technology and innovation in assessments needs to be evaluated and updated with experienced clinicians working at the coalface of concussion care to ensure it meets the pragmatic needs and evidence-based requirements needed to improve outcomes.

"The next step is to build a global community of practice where health professionals can support each other and share information while the evidence and clinical practice rapidly evolves.”

So, what are we doing? We have our own knowledge to action plan.

Advanced Neuro Education (ANE) is proud to support Your Brain Health, which offers baseline testing and is currently building a network of health professionals interested in concussion management.

ANE has developed a short online course ‘Concussion – what you need to know’ for the community with an update on concussion for parents, teachers, trainers, and coaches. Up to date information is provided about the complete end-to-end management of concussion.

ANE has also developed a comprehensive online course for health professionals, led by Clinical Lead Neurological Physiotherapist at Advanced Neuro Rehab, Liz Jemson-Ledger. The aim is to get consistent, evidence-based information out to health professionals, and combine with the knowledge/skills from years of clinical experience. The next step is to build a global community of practice where health professionals can support each other and share information while the evidence and clinical practice rapidly evolves. We also have a free webinar for health professionals that summarises the key proactive management strategies now used to help with concussion care.

With evidence, technology, community awareness and professional development, the future for concussion care looks promising, in fact it is already here.

Associate Professor James McLoughlin

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