concussion

What is concussion?

Concussion is a complex condition involving disturbance or injury to the brain or tissue surrounding the brain, normally following contact to the head, face or neck.

Typically, the onset of symptoms is rapid, however in some cases signs and symptoms of injury can be delayed, evolving over the coming hours or the next day. 

Whilst it is one of the most common sport and recreational injuries, it occurs just as easily at home or in the community, often associated with falls.  More recently it is being identified in children following playground accidents.

Pathophysiology of Concussion:

Concussion is often described in a similar way to mild traumatic brain injury. It is associated with changes in brain structure, pathways and function, often including damage to neurons & glial cells, grey matter and areas of diffuse axonal injury.

Impact-Acceleration is the key force responsible for diffuse axonal injury in the brain. It has the potential to deform the brain causing sheer stress and tension on the fibres and consequentially triggering a neuroinflammatory response. 

The studies into repeat concussions & sub-concussive head blows is still being investigated, however it is likely that a secondary head injury shortly after a concussion can significantly amplify the injury caused to the brain.

What are the symptoms of concussion?

Symptoms normally arise from one of 4 domains:

·       Somatic:  Headache, dizziness, nausea / vomiting and sensitivity to light or noise,

·       Cognitive: difficulty with concentration or memory 

·       Mood: irritability or sadness

·       Sleep: too much, too little or difficulty falling asleep

It is important to note that Concussion can occur even without the patient being knocked out or losing consciousness.  

Do I have Concussion? 

In the acute phase concussion is an evolving injury with rapidly changing clinical signs and symptoms. Because these signs and symptoms involve impaired brain function it is not recommended to self-diagnose, rather you need someone else to assess you.

If the incident occurs during a sporting event the player should be taken off the field immediately and the first assessment should be made quickly on the sideline by a trained professional.

Again, it is important to note that you don’t have to be knocked out or lose consciousness to sustain a concussion and symptoms may be delayed or slow to appear.

Testing for concussion involves a neurological assessment, tests for cognitive function including attention & memory and balance, reaction time and eye testing.  

Concussion is considered to be one of the most complex conditions in sports medicine to diagnose, assess and treat. If suspected you should seek assessment from a concussion trained physiotherapist or medical doctor.

Treatment of Concussion:

Once professionally assessed and diagnosed with concussion the first stage of recovery is rest for the initial 24-48 hours following the incident. In particular avoiding stimulating or loud environments and screen time.

Beyond this the patient is encouraged to gradually and progressively introduce gentle activity. This activity level should not bring on or worsen their symptoms.

Concurrent treatment of neck injury may be undertaken by your physiotherapist during this time.

If the symptoms have not resolved after 14 days, more specific rehabilitation will be commenced, this normally includes vestibular treatment & training and further assessment & management of the upper cervical spine alongside a specific exercise programme.

A physiotherapist will closely monitor your physical and cognitive progress during your rehabilitation including using special questionnaires or Buffalo treadmill testing with heart rate monitoring.

No two concussions are alike so all patients will require a personalised rehabilitation programme.

A Changing Diagnosis?

The majority of concussions involve short lived symptoms and resolve well to permit a quick return to sport, work and activity. However, some people experience delayed healing or develop Post-Concussion Syndrome where recovery is much lengthier and can take up to 12 months.

Post-Concussion Syndrome occurs in about 10% of cases and it is suggested that is represents a more severe form of brain injury. If you have had prior concussions or head injuries, or played contact sports for a long time you may be at a higher risk of developing this.

Return to Activity

All athletes, including elite and amateur participants should be managed using the same principles and processes for return to sport, activity or school.

1) Symptom limited activity – Daily activities that do not cause symptoms

2) Light aerobic activity – to increase heart rate and maintain brain function (e.g. Walking or stationary cycling at a slow pace).  No resistance training at this stage

3) Sport specific exercise – Slight increase in aerobic training and skill / technique training

4) Non-contact training – Increasing intensity slowly and with care, building towards full training. Resistance training can be commenced in a gentle graded fashion

5) Full contact – return to play

You should be monitored by a professional as you progress through the categories towards a return to full sport, in particular a final clearance should be given before commencing any contact sport.

 Written by Anthony D’Aloisio  M.Physiotherapy (Musc), B.Physiotherapy (Hons)

About the author
Anthony is a Musculoskeletal Physiotherapist who has trained and worked extensively in concussion assessment & management. Locally he has worked with Australian Rules footballers, overseas with Rugby Union players in New Zealand and race car drivers in the UK.

References:

McCroy, P et al (2018). Consensus statement on concussion in sport – the 5th international conference on concussion in sport held in Berlin, October 2016. Br J Sports Med, 51, 838-847.   

Choe, M.C. (2016). The pathophysiology of Concussion. Curr Pain Headache Rep, 20-42

Schnieder et al, (2017). Rest and treatment/rehabilitation following sport-related concussion: a systematic review. Br J Sports Med, (0), 1-7.