A concussion is a subcategory of traumatic brain injury. The consensus statement on concussion defines it as ‘a complex pathophysiological process affecting the brain induced by biomechanical forces. 80-90% of concussions resolve within 7-10 days. If concussion lasts longer than 10 days other potential diagnoses should be reconsidered. It should be noted that in some cases duration of recovery may be prolonged, particularly in children and adolescents.