November 14, 2014
March 23, 2015


Concussion – also known as  Commotio Cerebri, and a type of mild traumatic brain injury

Definition:  Concussion is defined as a mild head injury that  causes or leads to transient dysfunction of any or a combination of the following 8 domains:

  1. Post-traumatic Headaches
  2. Psychological
  3. Sleep
  4. Cognitive
  5. Cervical Spine
  6. Oculomotor
  7. Vestibular
  8. Autonomic

1) Post-traumatic headaches are classified as per international classification of headache disorders (ICHD) 1 however typically follow the patterns of other commonly classified headaches.

Tension type – bilateral tension band, that can last minutes to hours.  Typically intensity, frequency, and duration reduce with time from the concussion.

Migraine – 4-72 hours, 2 of the 4 following characteristics:  unilateral, pulsating, avoidance of physical activity, moderate or severe pain intensity, and any one of the two during the headache:  photosensitivity and/OR nausea/vomiting.

Occipital Neuralgia – Headaches typically one sided- occasionally bilateral, and radiate from occiput anteriorly towards temples and can be reproduced with pressure over the occipital nerve outlet

Cervicogenic (Whiplash associated disorder)- typically the headache is worsened with neck movements or held postures.

Secondary benign exertional headache:3

If patient has a preexisting headache condition, a concussion can cause a temporary worsening of those symptoms.

2)  Psychological – there is a significant psychological impact secondary to concussions.  Both new onset cases of anxiety and/or depression may occur, as well as a worsening of pre-existing anxiety/depression.

3)  Sleep dysfunction may include increased time to sleep, interrupted sleep and/or new vivid dreams.  It may also include alterations to the sleep-wake cycle.

4) Cognitive dysfunction is common after concussions and is often transient.  The dysfunction can involve reduce reaction time, memory deficits, decreased attention and difficulty focusing.  Neuropschological testing can be helpful in determining the extent and its implications on returning to learn and work.

5)  Cervical spine involvement is often in the form of a mild whiplash associated disorder, given that the forces required to cause a concussion often involve similar forces to the neck.   These can include, neck pain, neck tightness/stiffness, associated headaches, nausea, and dizziness.

6) Oculomotor dysfunction can also occur post concussion.  There are several complex neurological pathways involved, however coordination of vision, vestibulo-ocular pathway, ability to track moving objects, near-point convergence, ability to accommodate, focus and read can all be affected negatively after a concussion.  Symptoms can include headache, feeling foggy, light headed, dizzy, nauseous and eye-fatigue.   These typically occur with reading, watching screens, and being exposed to moving landscapes – (passenger in a car, walking through crowded areas).  These oculomotor symptoms typically resolve themselves with time, but may benefit from specialist assessment and certain treatments.

7)  Vestibular dysfunction – The vestibular system is similar to an inner gyroscope and helps coordinate balance as well as visual movements.   Symptoms can include poor balance, dizziness, light headed, difficulty progressing with exercise, and difficulty tracking objects or with eye movements.

8)  Autonomic dysfunction is one of the more recent to be described post concussion.  Effects include changes in heart-rate variability, orthostatic hypotensive effects and can included the following symptoms:  dizziness, light headedness, feeling fatigued and difficulty with progressing with exercise.

Symptoms:  Symptom duration can vary significantly.   Typical symptom duration in adults is up to 10-14 days, whereas in children up to 4 weeks is still considered within normal range (7).

Sport Concussion Assessment Tool #5 (SCAT5 – for pdf, see link below from BJSM) (2)

Headache Dizziness Nausea or Vomiting Dizziness
Balance Blurred Vision Light Sensitivity Sound Sensitivity
Feeling Slowed down In a fog Not feeling right Fatigue
Difficulty Concentrating Difficulty Remembering Difficulty Reading
Disordered Sleeping Sad/Depressed Nervous/Anxious Irritability


Medical Conditions Predisposing Patients to Prolonged Concussion Symptoms:

Neurological:  Epilepsy, Meningitis, Headaches, Migraines, Seizure Disorders

Psychological:  Anxiety, Depression, Post-Traumatic Stress Disorder

Learning:  Learning Deficits, Attention Deficit Hyperactivity Disorder

A history of prior concussions.

Differential Diagnosis:   Epidural hematoma, Subdural hematoma, subgaleal hemorrhage, facial fracture, whiplash associated disorder, post traumatic stress disorder, generalized anxiety disorder, major depressive disorder, subarachnoid hemorrhage, intracranial hypertension, chiari malformation.

On-field, see new SCAT 5(2) (view SCAT 5 updates lecture by Dr. David Lawrence)

In clinic, should include a neurological exam including Cranial Nerves, Head and scalp exam, Neck exam, Upper limbs, Coordination, Balance assessment and a neurocognitive assessment.

Neuro Exam:  Fundoscopy, PERLA, Visual Fields, Occulomotor exam, facial sensation, motor control, oral examination, shoulder shrug and neck exam.

Head And Scalp Exam:  Check for contusions, lacerations, aural and nasal for cerebral spinal fluid.

Neck Exam:  If on field, stabilize, then palpate posterior neck for midline boney tenderness, if none, proceed to neurological screen, and questioning about neck pain and sensation.  If normal proceed to AROM.  If normal, may clear neck.  If abnormal, stabilize and collar prepare for transportation to nearest hospital for further assessment.  If ambulatory – continue after AROM to have patient lying and assess for boney tenderness from C2-C7 and paracentral tenderness, often tender despite no complaints of neck pain.

Upper Limb:  Neurological assessment for power, sensation, reflexes, and coordination (finger to nose).

Balance:  modified BESS – Balance Error Scoring System.  This test has been described in two parts, first on solid ground and then on a foam pad.    Each step is observed for 20 seconds. See video below.

1) Feet together –  With feet together, head up, hands on the hips, and eyes closed

2) Tandem – With dominant foot in front of non-dominant foot, head up, hands on hips and eyes closed

3) One-leg stand – With patient standing on non-dominant leg, head up, hands on hips and eyes closed

These three steps can be repeated on foam (or a modified BESS is just using the first three steps).  A point is deducted each time an error is observed.  Errors include stepping out of place, raising hand from hip, or opening eyes.  Eg.  3 errors would result in a score of 27/30.

Cognitive Assessment:

On-Field Maddocks Score

Immediate Recall of 3-10 words (no hints)

World or Twirl spelled backwards

Months of the year in reverse order

Number sequences asked in reverse order (4,6,8 – “8,6,4”)

Serial 7’s – taking 7 away from 100

Delayed Recall of 3-5 words (no hints)

Not required for the clinical diagnosis of concussion.  They can be used to rule out other conditions that could pertain to the patient’s symptoms.

Bloodwork:   There are currently no evidence-based approved biomarkers for diagnosing concussion(7), and other blood tests are unrelated specifically to a concussion injury.  The following could be considered for persistent symptoms:
CBC (rule out occult infection, anemia), ferritin (Treat if ferritin < 30ng/mL in males, 50 ng/mL in females, if less than 2o consider venofer infusion …. see journal club on anemia), extended electrolytes (rule out hyponatremia, hypo/hypercalcemia), TSH, testosterone levels in males.

Cervical Spine imaging:  Cspine imaging is indicated for patients with midline tenderness, or with new neurogical symptoms following a concussion injury.   Consider Cspine xrays with Flexion/extension views, CT cspine or MRI neck to look for associated injuries.

MRI/CT head – although not required to diagnose concussion, can be helpful in ruling our some more sinister causes of patient’s symptoms such as intracranial hypertension, subdural hematoma, epidural hematoma, and chiari malformations.  CT Head rules can be helpful in determining who might need imaging after a concussive injury acutely after a trauma, however if your clinical assessment reveals either concerning neurological history or focal deficits on neurological exam brain imaging would be indicated as well.
CT head rules (6) –
High Risk (for Neurological Intervention)
1. GCS score < 15 at 2 hrs after injury
2. Suspected open or depressed skull fracture
3. Any sign of basal skull fracture*
4. Vomiting ≥ 2 episodes
5. Age ≥ 65 years
Medium Risk (for Brain Injury on CT)
6. Amnesia before impact ≥ 30 min
7. Dangerous mechanism ** (pedestrian, occupant ejected, fall from elevation(3′))


Management of an acute concussion that still has symptoms will include relative cognitive, physical and social rest until resolve or plateau of symptoms.    Management of symptoms should be targeted towards the deficits found during assessment which will be discussed below.  There are 3 main aspects to consider for patient recovery:  1) Return To Screen and Social Activity  2) Return to School (Return to learn) or Work (return to earn) and 3) Return to Sport.

New research supports and active rehabilitation approach to both acute and chronic concussion. This includes collaborating with a multi-disciplinary team and initiating cervical therapy, vestibular/balance therapy, occulomotor therapy, and/or exercise therapy where indicated. Growing evidence is supporting sub-symptom threshold aerobic exercise for the treatment of both acute and chronic concussion.

The new guidelines recommend early exercise and activity as patient can tolerate.   This may require that activities are modified to allow for full recovery.  Most commonly a 6-stage approach to return to sport is used:

Table 1 – Graduated return-to-sport (RTS) strategy (From Berlin consensus statement)(2):

Stage Aim Activity Goal of each step
1 Symptom-limited activity Daily activities that do not provoke symptoms Gradual reintroduction of work/school activities
2 Light aerobic exercise Walking or stationary cycling at slow to medium pace. No resistance training Increase heart rate
3 Sport-specific exercise Running or skating drills. No head impact activities Add movement
4 Non-contact training drills Harder training drills, eg, passing drills. May start progressive resistance training Exercise, coordination and increased thinking
5 Full contact practice Following medical clearance, participate in normal training activities Restore confidence and assess functional skills by coaching staff
6 Return to sport Normal game play


Return To Learn – This is a rather complex process.   A gradual progression to full school with testing and assignments is recommended similar to return to sport.   Ideally, the school and it’s educators  should be involved in the process.  After a short interim of rest, the author recommends return to school with modifications immediately after the rest period.

Modifications can include:  Visual symptoms – limit reading, assisted-note taking, not participating in group projects, music, or physical education classes, half-days, allowing patient to have breaks in quiet rooms for headache resolution, deferral of tests and exams, etc.  These can be tailored to the needs of the patient.  For further resources and more indepth information on return to learn, see the resources and lecture from Dr. James Carson from the 2017 UofT Primary Care Sports Medicine Conference (
The SCAT 5 recommends a 4 stage for return to learn:

Table 2 – Graduated return-to-school strategy -from SCAT 5 (2)

Stage Aim Activity Goal of each step
1 Daily activities at home that do not give the child symptoms Typical activities of the child during the day as long as they do not increase symptoms (eg, reading, texting, screen time). Start with 5–15 min at a time and gradually build up Gradual return to typical activities
2 School activities Homework, reading or other cognitive activities outside of the classroom Increase tolerance to cognitive work
3 Return to school part-time Gradual introduction of schoolwork. May need to start with a partial school day or with increased breaks during the day Increase academic activities
4 Return to school full time Gradually progress school activities until a full day can be tolerated Return to full academic activities and catch up on missed work

Light and Sound Sensitivity:
Sunglasses can assist with light sensitivity, as can hearing protection with noise sensitivity.   Screens should be avoided until the symptoms abate but if not possible or symptoms persist, the screen contrast can also be turned down.

Neck Symptoms:
Neck physiotherapy consisting of accupressure, ice/heat, passive massage and isometric exercises may assist a patient suffering an acute concussion, as well as potentially neuroproprioceptive exercises.

Oculomotor Dysfunction:
Visual therapy may be of benefit for patients struggling with visual distress.  Oculomotor and Dolls-eye exercises may begin if not causing or worsening symptoms.   These may consist of performing isolated eye movements (ie. with chin resting on a counter) following a union-jack formation at arm’s length in sets of clockwise and counter clockwise motions.   The distance may progressively shorten as tolerated by the patient.  Dolls-eye exercises are isolated neck movements in the same formation while the eyes stay focused in the middle of the union-jack.

Sleep Dysfunction:
Patients often will begin to have difficulty falling asleep starting as early as the first week and depending on symptoms up to the first couple of months.   As time to sleep increases, an increase in asymptomatic activity should be considered.   Also a discussion regarding sleep hygiene may help.  If it persists despite increased activity/sleep hygiene modifications, a sleeping-aid may be considered.

Depending on type of headache, intensity and time elapsed since the injury management may involve: activity modification, further shutdown, sunglasses, avoiding screens, or if persistent and higher intensity – medication.  Medication should not be used to allow the patient to carry on with activities that were otherwise causing them symptoms (for example screen use).   See article on persistent post-concussion symptoms for further details on medications (

Psychological Symptoms:
Concussion is associated depression and anxiety post-injury.  These symptoms are likely a combined effect from the injury and the withdrawal from activity.  If they increase a trial of increased activity – preferably symptomatic activity may be considered.  Low-intensity exercise should be considered – stationary bike at an intensity no greater than 60% of maximum heart rate.   A multi-disciplinary approach here is most important, and early referral to a sport psychologist is recommended.  Cognitive behavioural therapy can be employed to assist the patient in coping with the stresses of returning to school/work with symptoms.   Closely monitoring patient’s symptoms and risks is also important and selective serotonin re-uptake inhibitor (SSRI) or selective norepinephrine re-uptake inhibitor (SNRI) medication may be required to help reduce the patient’s symptoms.  See related webpage on review of medications:

Prolonged Symptoms:

See our article related to persistent symptoms at
See the Ontario Neurotrauma’s latest guidelines on prolonged symptoms for mild Traumatic brain Injury:

Dr. Neil Dilworth and Dr. David Lawrence (Sept 26, 2013, updated Dec 1, 2014, August 27, 2015, September 12, 2017 PR DL)


  1.  International Headache Society’s International Classification of Headache Disorders


3.  McCrory P  Headaches and Exercise.  Sports Med. 2000 Sep;30(3):221-9

4.  Targett C.  Exercise-induced headache. Emerg Med J. 2014 May;31(5):438. doi: 10.1136/emermed-2013-202725. Epub 2013 May 16.

5.  Nadelson C.  Sport and exercise-induced migraines.  Curr Sports Med Rep. 2006 Feb;5(1):29-33.

6. Stiell et al. The Canadian CT Head Rule for patients with minor head injury. Lancet. 2001

7. McCrory P, Meeuwisse W, Dvorak J, Aubry M, Bailes J, Broglio S, Cantu RC, Cassidy D, Echemendia RJ, Castellani RJ, Davis GA, Ellenbogen R, Emery C, Engebretsen L, Feddermann-Demont N, Giza CC, Guskiewicz KM, Herring S, Iverson GL, Johnston KM, Kissick J, Kutcher J, Leddy JJ, Maddocks D, Makdissi M, Manley GT, McCrea M, Meehan WP, Nagahiro S, Patricios J, Putukian M, Schneider KJ, Sills A, Tator CH, Turner M, Vos PE.  Consensus statement on concussion in sport-the 5th international conference on concussion in sport held in Berlin, October 2016.  Br J Sports Med. 2017 Apr 26. pii: bjsports-2017-097699. doi: 10.1136/bjsports-2017-097699. [Epub ahead of print]