Research Review By Dr. Brynne Stainsby©

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Date Posted:

October 2019

Study Title:

Concussion – Part I: The need for a multifaceted assessment

Author:

Schneider KJ

Author's Affiliations:

Sport Injury Prevention Research Centre, Faculty of Kinesiology, Hotchkiss Brain Institute, Alberta Children’s Hospital Research Institute, University of Calgary, Alberta, Canada.

Publication Information:

Musculoskeletal Science and Practice 2019; 42: 140-150. doi: 10.1016/j.msksp.2019.05.007.

Background Information:

Concussion is one of the most common injuries in sport and recreation (1, 2), accounting for 15% of the overall injury burden in youth and collegiate sports, with the highest risk reported in contact and collision sports (2-8). While there are an estimated 1.6-3.8 million sport-related concussions per year in the United States, it is suspected that most published estimates likely underreport concussion incidence, as most studies are based on hospital data and represent only the most severe cases (9, 10).

The 5th International Consensus Statement on Concussion in Sport defines concussion as a “brain injury that results from a traumatic blow to the head or body with subsequent force transmission to the head” (11, 12). It is considered a functional injury (rather than a structural one), and thus neuroimaging findings are typically normal (11, 12). As such, no specific test is diagnostic of a concussion, and assessment should be comprised of a history, neurological evaluation, balance tests, cervical spine exam and cognitive assessment (13, 14). A multifaceted assessment is recommended as concussions present differently in each patient (13, 15). A collaborative approach among family physicians, sports-medicine physicians, physiotherapists, chiropractors, athletic therapists, neurologists, neuropsychologists and others may be best for optimal care, depending on the case. Differential diagnosis, early management, re-evaluation, rehabilitation and the facilitation of return to school and sport are all critical components in the management of a patient with concussion.

Concussions can result in a number of symptoms, most commonly headaches, dizziness, fatigue, difficulty concentrating or remembering, neck pain or irritability (6, 17). Concussion should be suspected if one or more symptom, physical sign, behavioural change or cognitive impairment is present (18). Proper management requires education of stakeholders (coaches, parents, athletes, officials, etc.) regarding the potential symptoms, so that athletes will be immediately removed and assessed (18).

The purpose of this review was to summarize the current state of the evidence regarding the assessment of concussions, and assist in developing appropriate management plans in the acute and follow-up phases.

Summary:

Acute Concussion Assessment

Concussion Recognition Tool 5 (CRT5):
The CRT5 is meant for all stakeholders (including laypeople) to use when evaluating for a suspected concussion. It is not meant to be diagnostic tool, but to assist with the process of “recognize and remove” (19). It includes the following sequential process of assessment:
  • Step 1 - Recognize red flags: weakness or tingling/burning in the arms/legs, severe or increasing headache, seizure or convulsions, deteriorating mental status. If present, it is recommended an ambulance is called (19).
  • Step 2 - If no red flags are present, look for signs that suggest a concussion has occurred: balance difficulties, blank stare, slow to get up, disorientation, etc. (19).
  • Step 3 – Report of symptoms that may occur following concussion (19).
  • Step 4 (for athletes over the age of 12) – Five questions related to the sport event (inability to answer correctly may suggest concussion) (19).
  • The athlete/parent should be advised that the athlete is not to be left alone for the initial few hours, to avoid alcohol, recreational drugs and driving (19).
  • This tool is available HERE (19).
Sport Concussion Assessment Tool 5 (SCAT5):
  • The SCAT5 and Child SCAT5 are screening tools for healthcare providers, to be used on the sideline or in acute assessment settings. These tools may be used as a part of a multifaceted assessment, but should not replace a thorough clinical exam (20).
  • The SCAT 5 is comprised of subgroups of tests for immediate (screening for red flags, recording of observed signs, the Glasgow Coma Scale and Maddocks questions and a cervical spine screen) and office assessment portions (history, symptom report, cognitive assessment, neurological screen and balance assessment) (18, 20).
  • The Child SCAT5 includes both parent and child symptom report, neck pain rating, and a photograph for children to describe if they are not able to read (20).
The initial screen following a suspected concussion should also include evaluation for more serious injury such as intracranial bleeds, spinal cord injury or cervical spine fracture, using tools such as the Canadian CT Head Rules and the Canadian C-Spine Rules (21, 22).

Vestibular and Oculomotor Assessments:
  • The Vestibular/Ocular Motor Screen (VOMS) is a brief screen that asks patients to report symptom changes related to headache, dizziness, nausea and fogginess during five tests: smooth pursuit, horizontal and vertical saccades, near point of convergence distance (NPC), horizontal vestibular ocular reflex and visual motion sensitivity (23).
  • The VOMS has been shown to be able to screen for concussion at the time of clinical follow-up (5.5 days +/- 4.0 days following concussion; range 1-21 days) (23).
  • Signs and symptoms on VOMS can be used to suggest concussion, but should not replace a multifaceted clinical examination.
Assessment of Ongoing Symptoms Past the Initial 7-10 Days:
  • Up to 30% of children and youth may have ongoing symptoms four weeks following injury (8, 24). Those with high symptom intensity in the acute period, vestibulo-ocular dysfunction and cervical spine involvement may take longer to recover (25-27).
  • In most cases, patients have a number of persistent symptoms and a comprehensive evaluation for these patients should include a history, neurological evaluation, assessment of the cervical spine, balance, vestibulo-ocular and visual function, mood and neurocognitive screening (13, 28, 29).
  • A thorough history and physical examination can then be used to determine management.
Posttraumatic Headache:
  • Headache (HA) is one of the most common symptoms following concussion, affecting 40-86% of patients with a concussion (16, 30). Posttraumatic HA (by definition) occurs within seven days of the concussion (31) and may be associated with dizziness or balance deficits (32, 33).
  • Persistent posttraumatic HA may be reported as migraine or probable migraine, tension-type HA, cervicogenic HA, occipital neuralgia or medication overuse HA depending on the symptomatology (30, 31, 34, 35).
Cervical Spine (C/S) Involvement:
  • Neck pain (NP) is common following concussion, and it is possible that the trauma which caused the concussion may have also injured the neck (36, 37). Many symptoms are similar to those reported by those who have suffered a whiplash injury (38-40).
  • The upper C/S has a proprioceptive role and alterations in cervical afferent inputs may result in cervicogenic dizziness (41-43).
  • The myofascial system may be a source of HA or NP (44). Trigger points may be reported in the paraspinal and cervical muscles.
  • A C/S exam should include range of motion and palpation for segmental tenderness to detect facet joint dysfunction (45-47).
  • The cervical flexion rotation test has also been reported to have good diagnostic accuracy for C1-2-related cervicogenic HA (48,49).
  • Assessment of the deep cervical flexor muscles can be performed with the craniocervical flexion test (50). Individuals with NP have altered neuromotor control strategies (51-53).
  • The cervical flexor endurance test has been shown to be a useful test in distinguishing patients with whiplash associated disorders from healthy controls and may also be useful in patients with persistent concussion symptoms. The cervical extensor endurance and cervical rotation side-flexion test can also be used to assess the strength of the cervical musculature.
  • Assessment of sensorimotor control of the C/S can include the joint position error (the ability to relocate the head to a neutral position in space) (54), trunk relocation with stationary head (55), smooth pursuit neck torsion test (56), cervical torsion test (57) and/or the head perturbation test (29). Future research is required to understand the clinical utility of these tests (as well as the best combination to use) in concussion (58, 59).
  • One exploratory cohort study in youth ice hockey players compared a series of C/S measurements pre and post-concussion (29). In the acute post-injury period, 58% of subjects reported an increase in HA and 42% reported an increase in NP (29). Following injury, the concussion cohort performed significantly worse on measures of C/S function (29).
Dizziness/Balance Disorders:
  • Dizziness is a common symptom following concussion (60) and must be evaluated to rule out severe injury such as ischemic stroke (61-63). Careful differential diagnosis to identify the underlying cause is important as some are best treated medically, while others are amenable to vestibular rehabilitation (64-67). Afferent information from the proprioceptive, visual and vestibular receptors provide input regarding spatial location, and if one or more of these systems provides inaccurate information, alterations in balance/dizziness may result (68-70).
  • It is important to inquire about the nature of the dizziness (vertigo, disequilibrium, pre-syncope), duration, aggravating and relieving factors, and concurrent symptoms.
  • A variety of vestibular disorders may occur, including benign paroxysmal positional vertigo, labyrinthine concussion, otolith dysfunction, post-traumatic endolymphatic hydrops, post-traumatic migraine, brainstem or vestibulocerebellar dysfunction, cervicogenic dizziness and psychogenic dizziness (64-66, 68, 71-73).
  • Individuals may also present with findings of peripheral vestibular hypofunction (74). Initially, patients present with vertigo and unsteadiness, and as they recover, symptoms change to dizziness or lightheadedness. They may additionally present with nystagmus, alterations in vestibulo-ocular reflex, static and dynamic balance deficits and sensitivity to motion (75).
  • Cervicogenic dizziness is described as an imbalance or feeling of disequilibrium occurring with NP, stiffness or HA (77). It is believed to be caused by a dysfunction in the upper C/S, causing an alteration in cervical afferent input (77).
  • The clinical presentation of dizziness may change with recovery as function increases and ongoing reassessment is required to understand the source of dizziness and identify appropriate treatments (65). Clinicians should be encouraged to collaborate with those who have expertise in vestibular assessment and rehabilitation.
  • Standing and dynamic balance may also be altered following concussion (66, 78). The Balance Error Scoring System (BESS) is a clinical test with demonstrated reliability in collegiate athletes that evaluates postural sway (70, 79). Changes in gait parameters may also occur following concussion, such as tandem gait speed, which has been reported to be significantly slower in collegiate athletes acutely following concussion (80).
Cognitive, Mood & Behavioral Symptoms:
  • Individuals may report difficulty with dividing attention between movement or balance and a cognitive task following concussion (81, 82). A cohort study demonstrated improvements in time to compete a task of divided attention in youth ice hockey players during recovery following concussion (29).
  • Visual complaints such as double or blurred vision, difficulty reading or eye fatigue may be reported following a concussion (83-85). Convergence difficulties and accommodation disorders are the most common visual disturbances reported (85-88). Individuals may have difficulty completing visual tasks, and could be tested using the VOMS or King-Devick test (89). Referral to an optometrist, neuro-optometrist or ophthalmologist may be warranted in some cases.
  • Individuals with persistent symptoms may have difficulties with exertion, which may be demonstrated with symptom provocation during activity or intolerance to exercise (90-92). Both physical and cognitive exertional testing may be performed; however, clinicians should note that no valid measure of cognitive exertion exists. In adults, the Buffalo Concussion Treadmill Test (93) is a commonly used test of physical exertion, and the test is stopped at the onset of symptoms. It is also important that prior to physical exertion testing, clinicians carefully consider patient’s presentation and ensure safety (94, 95).
  • Up to 50% of collegiate athletes may report difficulty with concentration and memory following a concussion (though most report resolution within 10 days) (17, 96). A neuropsychology evaluation can assist with the underlying source of cognitive symptoms. As there is limited evidence to support cognitive interventions (97), if there are ongoing difficulties with cognitive function, referral to a neuropsychologist may be warranted (98).
  • A small number of athletes report feeling irritable or sad following a concussion, and typically, these symptoms resolve within the first week (17). Concussion can trigger mental health disorders however, and in patients with pre-existing anxiety or depression, recovery may be prolonged (27). Emotional symptoms tend to present later in the recovery period, and thus it is important to recognize concurrent mental health concerns and refer the patient to his/her physician, or a psychologist, psychiatrist or neuropsychologist for appropriate management.
  • Up to 20% of high school and collegiate athletes have reported difficulties with sleep following concussion (17). Assessing sleep is very important as poor sleep has been associated with poor health outcomes (99, 100). Poor sleep quality may be secondary to pain, and thus sleep posture should be assessed and modified if possible. It has also been hypothesized that autonomic dysfunction may contribute to sleep difficulties (101). Following mild traumatic brain injury, insomnia has been associated with higher levels of disability and pain, and poor sleep quality predicted poorer mood, cognitive ability, and post-concussion symptoms one year following concussion (102, 103). If ongoing sleep difficulties persist, referral to a physician with expertise in sleep management may be warranted.

Clinical Application & Conclusions:

Concussions have a varied clinical presentation and a thorough assessment of symptoms is essential. If a concussion is suspected, screening to rule out red flags and serious pathology is crucial. Health care professionals may also use the SCAT5 or Child SCAT5 for sideline or immediate assessment in the office, but their use is merely a component of a thorough clinical examination. An initial period of cognitive and physical rest is recommended, and in most cases, will be followed by step-wise return to activity.
 
While most patients will experience an uncomplicated recovery, if symptoms persist beyond 10 days, a detailed, multifactorial (and possibly multidisciplinary) assessment is required. In these cases, referrals to specialists with experience in managing concussions will likely be indicated. Clinicians should also consider screening for concurrent mental health diagnoses, which may be aggravated by a concussion. A multidisciplinary team with experience managing concussions will facilitate optimized care of these complex cases.

Study Methods:

The was a narrative review (‘masterclass article’) and as such the methodology was not described.

Study Strengths / Weaknesses:

Strengths:
  • This review provides a thorough overview of the symptoms which may present in the immediate post-concussion period, as well as symptoms which may persist.
  • It also highlights the need to recognize, remove and re-evaluate athletes if concussion is suspected.
  • A variety of tests which can be used to screen for concussion and test for post-concussion symptoms were presented.
  • Common clinical screening tools (SCAT5 and Child SCAT5) which can be used to assess patients were also summarized.
Weaknesses:
  • The primary limitation of this paper is the lack of a description of the methods employed.
  • The author does not include statements regarding the research question, search strategy or if/how the quality of the included evidence was appraised.
  • Although a number of tests are presented in this review, the psychometric properties are not discussed, and clinicians should interpret them with caution pending further research in concussion populations (the author did mention this when appropriate).

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