Western Journal of Emergency Medicine. Journal of Neurology, Neurosurgery, and Psychiatry. During development, rapid changes in synapses, myelination, and metabolism occur, with the brain achieving adult-like connections by the mids see Figure Although many youth and amateur boxers wear protective gear and follow rules that are different from those for professional boxers, a primary goal of boxing is to attack the head and face of the opponent, which often results in a concussion or more severe brain injury Jordan, Findings from Soccer Studies In soccer, athletes experience repetitive head impacts from using their heads to strike the ball for passing and shooting.
Miller first used the term "accident neurosis" to refer to the syndrome which is now called PCS and asserted that the condition only occurs in situations where people stand to be compensated for the injury.
A related concern is the effect of a history of concussions on cognition and brain physiology. Of concussions documented during a 6-year period involving more than 1, athletes, 45 concussions were diagnosed within the same day of injury, and athletes were removed immediately from the competition.
Histological samples were collected at 1, 3, or 7 days post injury, and cognitive function was assessed 14 days post injury with the MWM. Dementia Pugilistica Much of the current understanding of the neuropathology of chronic traumatic brain injury in athletes comes from classical studies of professional boxers who experienced repeated impacts to the head throughout their careers Corsellis et al.
Adapted from Casey et al. Further, Lew et al. By contrast, in the more common non-centroidal head impacts, linear and rotational accelerations are not correlated significantly, and the rotational acceleration component of the head response correlates most strongly with the average and peak brain deformations.
Moreover, animal studies show that the pathologies differ in myelinated versus unmyelinated fibers Reeves et al. Computational models are used to estimate the tissue distortions and stresses that may result from the kinematics of a rapid head motion or head impact, but they are valuable for understanding mechanics only when they use life-like tissue stiffnesses.
Clinical history and comorbid factors, such as complications from other medical conditions and exposures e. The greatest cumulative effects on adenosine triphosphate, N-Acetylaspartic acid NAAredox, and oxidative damage were all seen with the 3-day injury interval.
Although most of the studies compare single and repeat injury to sham, few studies have incorporated a design in which the interval between injuries was varied. Microscopically, the consistent findings were the presence of tau-positive NFTs and neuropil threads, most prominently in frontal, parietal, and temporal neocortex.
They continued to feel debilitated by post-concussive symptoms and experienced symptoms of anxiety and depression. Covassin and colleagues found no differences on any ImPACT composite test between athletes with no previous concussions and those with one previous concussion.
Until these foundational biomechanics are defined, it will be premature to make predictions of concussions based Page 67 Share Cite Suggested Citation: In addition, NFTs in boxers are often clustered as multifocal patches in the dorsolateral frontal cortex, temporal cortex, and orbital gyri, and they show unique perivascular distributions.
Given that cerebral substrate supply and utilization are linked, it is not surprising that the developmental profile of cerebral glucose uptake mirrors that of CBF in both animals and humans Nehlig et al. Timing of concussion diagnosis is related to head impact exposure prior to injury. In summary, studies of the consequences of heading in soccer have obtained mixed results, with more recent studies showing no relationship between heading and neuropsychological impairment.
Studies of Multiple Concussions As discussed in Chapter 2there is some evidence from both animal studies and research involving humans that the brain is at increased risk while recovering from a concussion.
College-Age Athletes Ten studies of college-age athletes were reviewed. Social suport and recovery from sport injury: The human data may also be limited by inaccuracies in self-reports of concussions and difficulties in adequately adjusting for varying histories of previous impact exposures.
Although this research involved rodents, epidemiological evidence is consistent with children having poorer outcomes than adolescents or adults following mTBI.
Each of these gaps in knowledge about concussion thresholds limits the ability of computational models to predict whether a concussion would occur from a specific head rotation or impact.
Early research using magnetic resonance imaging MRI and cognitive tests found no significant cognitive impairments or differences on MRI scans among soccer players, boxers, and track and field athletes Haglund and Ericksson, Because PCS symptoms are so varied and many can be associated with a large number of other conditions, doubt exists about whether the term "syndrome" is appropriate for the constellation of symptoms found after concussion.
Chronic Traumatic Encephalopathy The identification of tau-positive NFTs in boxers with dementia pugilistica raises the question of whether this is an early and a consistent diagnostic feature in repeated traumatic brain injury.
Kaminski and colleagues conducted two studies with 71 and female collegiate soccer players. British Journal of Sports Medicine. While they found significant differences in all four composite scores at day 1 and in two composite scores at day 5 verbal memory and reaction timethey did not control for baseline scores or compare the number of significantly changed scores CRI between groups.
Similarly, animal models that allow more head rotation after impact or enhanced head or brain movement produce more severe brain injuries Foda and Marmarou, ; Marmarou et al.stage 4 - dementia and aggression (the stage of CTE correlated with duration of football play, survival after football and age at death.
there was an increased. `` Repeated Sports-Induced Concussions as a Youth Increased Adult Hyper-Aggression Abstract Advancing research is revealing more potential causes for adult behavioral problems.
Concussions have long been suspected as a source of behavioral problems, with sports induced concussions. Concussions which commonly occur among athletes can cause damage to the brain that lasts for decades, according to research presented at a recent AAAS Annual Meeting.
increased physical activity, an increased number of competitive sports programs for both male and female adolescents, and the popularity of professional contact sports, adolescent involvement in competitive sports has been on the rise and is continuing in a similar trend.
Participation in youth sports and sports-related activities has risen dramatically over the past several decades, given the increased number of programs for both male and female youths. Furthermore, the recognized benefits of physical fitness resulted in more adolescent involvement in competitive sports.
Studies of Repetitive Head Impacts. As with much of the clinical literature on the consequences of concussions in sports, the generalizability of many studies of the effects of repetitive head impacts is limited by methodological weaknesses.Download