Definition of Concussion
A complex pathophysiological process affecting the brain, induced by traumatic biomechanical forces. Several common features that incorporate clinical, pathologic and biomechanical injury constructs that may be utilized in defining the nature of a concussive head injury include:
- Concussion may be caused by a direct blow to the head, face, neck or elsewhere on the body with an “impulsive force transmitted to the head.
- Concussion typically results in the rapid onset of shortlived impairment of neurologic function that resolves spontaneously.
- Concussion may result in neuropathologic changes, but the acute clinical symptoms largely reflect a functional disturbance rather that a structural injury.
- Concussion results in a graded set of clinical symptoms that may or may NOT involve a loss of consciousness. Resolution of the clinical and cognitive symptoms typically follows a sequential course; however it is important to note that in a small percentage of cases, post concussive symptoms may be prolonged
- No abnormality on standard neuroimaging studies is seen in concussion.
- Canadian Pediatric Society definitions is based on the previous definition with an emphasis that concussion is an impact related MTBI.
Incidence
- Year 2000, Wiler et al reported an overall head injury rate of 3.98 injured children per 100 in the province of Ontario
- Bakhos et al, ER visits 4/1000 8-13 year olds and 6/1000 in 14-19 year olds
- 6 to 3.8 million sport related concussions in US per year
- Often under reported
- Echliln Study 2010 – Incidence rate 3.3 times higher that previously reported.
