Chronic Traumatic Encephalopathy (CTE)
Chronic traumatic encephalopathy (CTE) is a form of encephalopathy that is a progressive degenerative disease, which can currently only be definitively diagnosed post-mortem, in individuals with a history of multiple concussions and other forms of head injury.
In March 2014, researchers announced the discovery of an particle created by the brain which has been shown to contain trace proteins indicating the presence of the disease, however, a test is not yet available.
The disease was initially found in those with a history of boxing.
CTE has been most commonly found in professional athletes participating in American football, ice hockey, professional wrestling and other contact sports who have experienced repetitive brain trauma.
It has also been found in soldiers exposed to a blast or a concussive injury.
Reports of CTE have steadily increased in younger athletes, most likely due to increased awareness of the issue and perhaps due in part to athletes becoming bigger and stronger producing greater force in collisions.
Dr Bennet Omalu, M was the first forensic neuropathologist to identify chronic brain damage as a factor in the deaths of some National Football League players. He discovered pathological signs of CTE in the brain of Pro Football Hall of Fame player Mike Webster in 2002.
Dr. Ann McKee is a leading authority on CTE who has found evidence of CTE in over 70 of the athletes that she has examined, including three NHL and 18 NFL players.
- “a distinct disease with a distinct cause, namely repetitive head trauma”
- (Ann McKee, MD, CSTE co-director and neuropathologist)
- CTE diagnosed in >20 former NFL players since 2002
- Youngest: 18-year-old boy who suffered multiple concussions in high school football
- University of Michigan’s Institute for Social Research reports that Alzheimer’s -like memory- related diseases appear to have been diagnosed in the league’s former players at a rate of 19 times normal for men ages 30 – 49
- Chronic Neurological Impairment (CNI) terminology also used
The disease features characteristic degeneration of brain tissue and the accumulation of tau protein.
A small group of individuals with CTE have chronic traumatic encephalomyopathy, characterized by motor neuron disease symptoms and mimics Amyotrophic Lateral Sclerosis (ALS) (known in the United States as Lou Gehrig’s disease).
Progressive muscle weakness and balance and gait problems seem to be early signs.
The primary physical manifestations of CTE include a reduction in brain weight, associated with atrophy of the frontal and temporal cortices and medial temporal lobe.
Individuals with CTE may show symptoms of dementia, such as memory loss, aggression, confusion and depression, which generally appear years or many decades after the trauma.
- Cerebellar atrophy/scarring
- Degeneration of the substantia nigra
- Diffuse atrophy and ventricular dilitation
- Atrophy of the cerebral hemispheres, medial temporal lobe, thalamus, mammillary bodies and brainstem
- Thinning of the hypothalamic floor
Repeated concussions and injuries less serious than concussions (“sub-concussions”) incurred during the play of contact have not definitively been found to result in CTE but are implicated.
In the case of blast injury, a single exposure to a blast and the subsequent violent movement of the head in the blast wind can cause the condition.
Its true prevalence and the risk of CTE following concussion are currently areas of intense study, and genetic predispositions are possible.
- Cumulative effects of concussion represents a serious concern in sports
- True prevalence is unknown
- Increased exposure is an important risk factor for CTE
- However the exposure threshold is unknown (How many concussions are too many?)
- Genetics may play a role
In August 30, 2013, the NFL reached a $765 million settlement with the former NFL players over the head injuries.
The settlement created a $675 million compensation fund from which former NFL players can collect from depending on the extent of their conditions.
Severe conditions such as Lou Gehrig’s disease and post-mortem diagnosed chronic traumatic encephalopathy would be entitled to payouts as high as $5 million.
From the remainder of the settlement, $75 million will be used for medical exams, and $10 million will be used for research and education.
However, in January, 2014, U.S. District Judge Anita B. Brody refused to accept the agreed settlement because “the money wouldn’t adequately compensate the nearly 20,000 men not named in the suit“ and the settlement is now unlimited.
Likewise, College Sports in the USA have also attempted to reach settlements and it is likely that other countries and sports will follow suit.