Athletes who recover more slowly from concussion may be able to return to play with an additional month of recovery beyond the typical recovery time, according to a new study published in the journal Neurology. Slow recovery was defined as taking more than 14 days for symptoms to resolve or taking more than 24 days to return to play, both of which are considered the typical recovery times for about 80% of athletes with concussion.
“Although an athlete may experience a slow or delayed recovery, there is reason to believe recovery is achievable with additional time and injury management,” said study author Thomas W. McAllister, MD, of the Indiana University School of Medicine in Indianapolis. “This is an encouraging message that may help to relieve some of the discouragement that athletes can feel when trying to return to their sport. While some athletes took longer than 24 days to return to play, we found that three-quarters of them were able to return to sports if given just one more month to recover.”
The study looked at 1751 American college athletes diagnosed with a concussion by a team physician. Of Male athletes (63%) participated primarily in football, soccer and basketball. Female athletes (37%) participated primarily in soccer, volleyball and basketball.
Participants were evaluated five times: within six hours after their injury, one to two days later, once free of symptoms, once cleared to return to play and at six months.
Participants reported symptoms daily to medical staff, up to 14 days following injury and then weekly if they had not yet returned to play.
A total of 399 athletes, or 23%, had a slow recovery.
Researchers found that of the athletes who took longer than 24 days to return to play, more than three-fourths, or 78%, were able to return to play within 60 days of injury, and four-fifths, or 83%, were able to return to play within 90 days of injury. Only 11% had not returned to play six months after injury.
For the slow recovery group, the average time for returning to play was 35 days after injury, compared to 13 days in the overall group.
“The results of this study provide helpful information for athletes and medical teams to consider in evaluating expectations and making difficult decisions about medical disqualification and the value of continuing in their sport,” McAllister said.
A limitation of the study is that participants were all collegiate varsity athletes and may not be representative of other age groups or levels of sport, and the results may not apply to other types of mild brain injuries.
Although bones are considered a mostly structural component of the human body, bones are in fact active living tissues that can respond to applied mechanical forces. For example, martial arts training, with its kicks, punches and throws, has been shown to increase bone mineral density in the arms, legs and spines of practitioners.
At present, it is unclear whether this thickening of the skull is beneficial or detrimental: theoretically, a thicker skull is a stronger skull, suggesting that this may be the bone’s attempt to protect the brain from subsequent impacts.
“This is a bit of a conundrum,” Assoc Prof Semple said. “As we know, repeated concussions can have negative consequences for brain structure and function. Regardless, concussion is never a good thing.”
The team hopes that the microstructural skull alterations caused by concussion are now considered by researchers in the field to better understand how concussions affect the whole body.
A form of mild traumatic brain injury, concussion have been linked to long-term neurological consequences if they happen repetition.
While most studies focus on its effect on the brain and its function, they largely ignore the overlying skull bones.
Study collaborator Professor Melinda Fitzgerald, from Curtin University and the Perron Institute in Western Australia, has previously shown that repeated concussive impacts lead to subtle problems with memory, and evidence of brain damage.
In this new study, high-resolution neuroimaging and tissue staining techniques were used in a pre-clinical animal model, and revealed an increase in bone thickness and density, in close proximity to the site of injury.
“We have been ignoring the potential influence of the skull in how concussive impacts can affect the brain,” Associate Professor Semple said. “These new findings highlight that the skull may be an important factor that affects the consequences of repeated concussions for individuals.”
Future studies are planned, with collaborator and bone expert Professor Natalie Sims from St Vincent’s Institute of Medical Research in Melbourne, to understand if a thickened skull resulting from repeated concussions alters the transmission of impact force through the skull and into the vulnerable brain tissue underneath.
Concussion may cause different types of brain damage which lead to similar symptoms in children, according to research published in eLife. A new way of studying concussions could help inform the development of future treatments.
While most children fully recover after a concussion, some will have lasting symptoms. The findings help explain the complex relationships that exist between symptoms and the damage caused by the injury.
The researchers found that certain combinations of brain damage were associated with specific symptoms such as attention difficulties. Other symptoms, such as sleep problems, occurred in children with multiple types of injuries. For example, damage to areas of the brain that are essential for controlling sleep and wakefulness could cause challenges with sleeping, as could damage to brain regions that control mood.
The brain’s white matter holds clues
To do this, they examined how damage to the brain resulting from concussion affected its structural connection network, known as white matter. They then used statistical modelling techniques to see how these changes related to 19 different symptoms reported by the children or their caregivers.
Analysing symptoms may advance treatment
“Despite decades of research, no new treatment targets and therapies for concussions have been identified in recent years,” said lead author Guido Guberman, a Vanier Scholar and MDCM Candidate at McGill University. “This is likely because damage to the brain caused by concussions, and the symptoms that result from it, can vary widely across individuals. In our study, we wanted to explore the relationships that exist between the symptoms of concussion and the nature of the injury in more detail.”
Guberman and his colleagues analysed data collected from 306 children, aged nine to 10 years old, who had previously had a concussion. The children were all participants in the Adolescent Brain Cognitive Development (ABCD) Study.
“The methods used in our study provide a novel way of conceptualising and studying concussions,” says senior author Maxime Descoteaux, a Professor of Computer Science at Université de Sherbrooke. “Once our results are validated and better understood, they could be used to explore potential new treatment targets for individual patients. More broadly, it would be interesting to see if our methods could also be used to gather new insights on neurological diseases that likewise cause varied symptoms among patients.”
There is more risk of suffering concussions or being misdiagnosed with head trauma is greater among fighters who rapidly cut weight before bouts, usually by dehydrating, researchers have revealed for the first time.
More than 60% of athletes in combat sports such as boxing and mixed martial arts (MMA) reported that their symptoms worsened after they dehydrated to make strict weight classes.
These controversial weight cutting techniques involve stop drinking water and endure long periods in saunas.
MMA athletes reported concussion severity to be 40% higher compared to other sports, particularly boxing – believed to be due to the mix of striking and contact with the ground.
Published in the Clinical Journal of Sports Medicine, the study comes after a series of tragedies associated with weight cuts, with some athletes even dying in the attempt to achieve a perceived competitive edge, by competing in a smaller weight class.
They found that as competitors dramatically dehydrate themselves to meet stringent weight classes, the associated symptoms may ‘muddy the waters’ of baseline concussion testing, due to similar symptoms.
This is because the symptoms of hypohydration – where competitors enter a water deficit – match concussive signs, such as dizziness, headaches, and lethargy.
This study has spurred further probes into the neurological implications of rapid weight loss. The researchers have called on governing bodies to check fighters’ hydration levels before fights.
Researcher Nasir Uddin, from St Mary’s University, said: “This study shows that current concussion testing does not account for the crossover of symptoms from being dehydrated, and is potentially putting fighters at risk.
“Not only is cutting weight through dehydration in and of itself dangerous, but it might actually exacerbate concussion symptoms and, even more concerningly, means medical professionals may actually misdiagnose it.
“Going forward, governing bodies should ensure hydration and baseline concussion symptoms are taken into account before and after bouts.”
The study surveyed more than 130 anonymous athletes representing six combat sports, all aged 18 or above and who had previously cut weight.
It also found that 65% of the fighters had an experience of a weight cut “not going to plan”, suffering a lack of energy, strength, power, coordination or increased susceptibility to being ‘rocked’ during a bout.
This means the dangerous practice may not offer a competitive advantage after all.
Dr Jamie Tallent, from the University of Essex, said: “This is perhaps the most surprising finding that not only are weight cuts dangerous – they leave fighters at a disadvantage more often than not and may exacerbate the risks of being further injured.”
A clinical study from Lund University in Sweden has shown that long-term problems such as dizziness and difficulty focusing after a concussion originate in an injury to the vestibular nerve. The researchers published their findings in the Journal of Neurotrauma.
Concussion resulting from a blow to the head is a hazard in many sports. In American football, where players who have suffered from repeated concussions have developed dementia, severe depression and cognitive impairment.
Concussion usually has only temporary symptoms, but an increasing number of athletes experience long-term problems that make it difficult to work, go to school or play sports. The symptoms are aggravated by activity or impressions and include headaches, depression, anxiety, nausea, difficulty focusing and problems with balance.
“It has been unclear what causes the symptoms, and it is difficult for healthcare professionals to help these athletes. We wanted to investigate this further to find out what really causes the symptoms,” said Professor Niklas Marklund, one of the study’s researchers.
The study included 21 healthy athletes without previous trauma to the head, and 21 athletes who all suffered from sports-related concussions and who had experienced persisting symptoms for more than six months. The researchers used a 7-Tesla MRI, to study the athletes’ brains to understand more about what caused the symptoms. They discovered impaired function of the balance organs in the inner ear of 13 athletes in the group with long-term problems. In the group of healthy athletes three people had similar findings.
“The test results show that the injury is located to the vestibular nerve, which is connected to the semicircular canals in a cavity inside the skull, and which is directly adjacent to the cochlea in the ear. These injuries lead to the inward nerve impulses not working properly, and the brain therefore does not receive important information about body movements and sensory impressions required to maintain a good balance,” said Anna Gard, doctoral student at Lund University and first author of the study.
Concussion often results from the head rotating too fast.
“We have not examined athletes with short-term problems after blows to the head, so we cannot say anything about them. This study applies to athletes with prolonged symptoms after concussion. The rotation of the head that occurs in connection with a concussion could lead to a stretch of the vestibular nerve, which then leads to impaired function. Now that we have more knowledge about where the problems are located, it is easier to find possible therapies that could help these athletes,” concluded Prof Marklund.
The BRAIN study worked with nearly 150 retired elite male players now aged 50+ who played for either England, Oxford University or Cambridge University in the pre-professional era.
While no worsening of cognitive function was seen in the group overall and in the under 75s, the study did find that over 75s with three or more rugby-related concussions during their career (14/48) had significantly worse cognitive function on average than those who had experienced fewer concussions, and may be at risk of future cognitive problems.
The findings have implications for the clinical management of older ex-rugby players, and possibly ex-players of other contact sports who may be at risk of impaired cognition, the team noted.
Given the age of the 75+ participants, these findings therefore primarily relate to the pre-professional era in rugby. Additional work is needed for younger players, particularly when reaching older ages when more cognitive problems manifest.
This study marks the first to attempt to measure cognitive function in a large number of former players and to link this to their concussion and playing history. Previous studies which have focussed on younger players have found little or no association between concussions and reduced cognitive function.
The study’s last author, Professor Neil Pearce from the London School of Hygiene & Tropical Medicine, said: “Evidence is accumulating on the possible long-term health risks in former contact sport athletes. However, each sport is different and there is currently little evidence from rugby players. This study adds to this knowledge gap, and shows that playing elite rugby may affect cognitive function in older age. It’s important more research is conducted to confirm this, and on those who played in the early years of professional rugby.”
One partial explanation for the reduced cognition in the 75+ groups could be that the former elite rugby players in this study were mostly highly educated, therefore having a higher average cognitive function at the start of their playing careers.
Dr Valentina Gallo, from the University of Groningen in the Netherlands (formerly at Queen Mary University of London), another of the Principal Investigators of the BRAIN study, and study first author, said: “Our findings are in line with those of previous studies, and perhaps highlight that the high cognitive reserve in this study group may have masked the initial phases of any cognitive problems they experience. We’ll be following up on this group of players to shed further light on our findings.”
Participants took part in an extensive set of tests capturing physical and cognitive capabilities. with cognitive function measured using the Pre-clinical Alzheimer Cognitive Composite (PACC) score, which combines tests that assess episodic memory, timed executive function, and global cognition.
After adjusting for possible confounding factors including age, smoking and player playing position, participants over 75 with three or more concussions scored about two points lower on the PACC score. This indicates a difference in cognitive function that can only be detectable with this sort of detailed testing, but which may indicate an increased risk of developing neuro-degenerative conditions.
A total of 116 (80%) respondents reported at least one rugby-related concussion. Among the concussed, the number of rugby-related concussion ranged between one and 25, with a median of two. The number of rugby-related concussions was not associated with the position they played or with length of rugby career.
Dr Simon Kemp, RFU Medical Services Director, said: “This study, that started in 2017, adds to our developing understanding of the potential long term consequences of head impacts and concussions. The agreed group of participants were aged 50+ principally because of the greater likelihood that we might detect any neurocognitive decline if present. It is important to also conduct research with younger retired players.
A study found that CT scans for concussion patients provide crucial information on their risk for long-term impairment and their potential to make a complete recovery, and points to the need for more follow-up.
In the UC San Francisco-led study, researchers examined CT scans of 1935 patients, aged 17 and over, whose neurological exams met criteria for concussion, or mild traumatic brain injury (TBI). Outcomes for moderate and severe TBI have been linked to CT imaging features, but this may be the first time this link has been identified in patients with concussion. This contradicts previous research which had found no prognostic significance of specific types of CT abnormalities.
“Radiologists who routinely read trauma scans know intuitively that patterns of intracranial injury on CT are not random,” said first author Esther Yuh, MD, PhD, of the UCSF Department of Radiology and Biomedical Imaging. “We showed there are patterns of injury, that some of these are associated with worse outcome than others, and that they provide a window into mechanisms of injury that is reproducible across large studies.”
The study was published online in JAMA Neurology.
“Although concussions are referred to as mild traumatic brain injuries, there is nothing mild about some concussions,” explained senior author Geoffrey Manley, MD, PhD, professor and vice chair of neurological surgery at UCSF and chief of neurosurgery at Zuckerberg San Francisco General Hospital. “Patients with concussion may suffer from prolonged headache, poor sleep and impaired concentration, and they are at higher risk of self-medicating with drugs and alcohol. Concussion can also contribute to depression and anxiety, and increase the risk for suicide. We need to view concussion not as an event but as a disease requiring physician follow-up after a patient is discharged from the hospital.”
The participants were enrolled by the brain injury research initiative TRACK-TBI, of which Manley is the principal investigator. To enrich the number of so-called complicated concussions, the researchers drew exclusively from patients who had been seen at hospitals with level 1 trauma centres. This meant 37 percent of study participants had a positive CT, significantly more than the 9 percent of positive CTs from patients in US emergency departments.
The most common patterns of injury, affecting more than half of CT-positive patients, were combinations of subarachnoid haemorrhage (SAH), subdural haematoma (SDH), and/or contusion, which may be caused by injuries such as falls from standing. About 7 percent had intraventricular haemorrhage (IVH) or petechial haemorrhage, caused by head rotation as in some sporting, scooter and automobile accidents; and 5 percent had epidural haematoma (EDH), often seen in sports injuries such as being hit with a baseball.
Average age of the patients was 41 and 66 percent were male. They were followed-up at two weeks, and at three-, six- and 12 months following injury. Patients in the SAH/SDH/contusion group failed to make a complete recovery at 12 months post-injury and had a range of outcome impairments, from mild to more severe.
Patients in the IVH/petechial haemorrhage group tended toward more severe impairments, in the lower-moderate disability range, a level potentially affecting multiple areas of function, such as employment, social and leisure activities, up to 12 months post-injury. Patients with EDH fared significantly better and demonstrated complete recovery by their six-month assessment.
Results from CENTER-TBI, a parallel brain injury research group that had enrolled 2594 participants at European trauma centres. validated the findings. “The confirmation of the findings in an independent cohort confirms the fidelity of our results,” said Manley, adding that patients with EDH were one exception, with incomplete recovery lingering for months longer than those patients followed by TRACK-TBI. However, more severe outcomes were not seen at any point in either study.
The researchers noted that even among concussion patients with positive CT scans, only 39 percent get follow-up care, which should be routine. They also cautioned that their findings are not a call for increased CT use, which has radiation dose concerns and is restricted to known or suspected concussions.
Indeed, a recently approved rapid hand-held blood test may reduce the amount of CT scans. Manley found this test was more sensitive than CT in detecting concussion. The blood test measures biomarkers associated with TBI, which were nearly 52 times higher in MRI-identified concussion patients than in healthy participants.
In addition to challenging the belief that CT features in concussion are not relevant, the researchers are also challenging the idea that concussion is “what the patient brings to the injury,” said Manley, who is also affiliated with the UCSF Weill Institute for Neurosciences. “In moderate and severe TBI, it is anecdotally taught that outcome is determined by ‘what the injury brings to the patient,’ while concussion is determined by baseline characteristics like age, sex and years of education. While the study confirms the importance of these characteristics, we show that in some concussion cases, poor outcomes are also attributed to ‘what the injury brings to the patient.'”
Journal information: Yuh EL et al., Pathological computed tomography features associated with adverse outcomes after mild traumatic brain injury, JAMA Neurology, July 19, 2021.
A new test has been found to effectively pick up concussion biomarkers in the saliva of rugby players.
This paves the way for a non-invasive, easy-to-use pitch-side test to rapidly detect concussions for early treatment. Concussion is a serious problem in contact sports, with players such as college American Football athletes consistently underestimating its risk. Missing a concussion can have a range of consequences, from delayed recovery to more serious (albeit rare) injuries such as traumatic brain swelling.
Detecting concussions requires an assessment by a clinician of the signs and symptoms of the injury. However, recent advances in DNA sequencing technology have made it possible to use small non-coding RNAs (sncRNAs) as biomarkers in rapid tests. sncRNAs regulate the expression of different cellular proteins associated with various diseases, such as cancer and Alzheimer’s disease.
t is thought that since saliva can receive cellular signals directly from the cranial nerves in the mouth and throat, biomarkers from a brain injury would quickly show up.
A panel of 14 sncRNAs differentiated concussed players from those where traumatic brain injury had been suspected but ruled out, and from the comparison group, both straight after the game and 36–48 hours later.
Over two seasons, samples were collected before the rugby season began from 1028 players from the two elite professional tiers, and during standardised ‘gold standard’ head injury assessments at three time points—during the game, afterwards, and 36–48 hours later from 156 of these players .
The researchers also took saliva samples from a comparison group of 102 uninjured players, as well as 66 with muscle or joint injuries, and so had not had head injury assessments.
However, the researchers stressed that the observational study nature and design of this study cannot show that the biomarker test is any better than a gold standard clinical test for concussion.
“In community sport, [sncRNAs] may provide a non-invasive diagnostic test that is comparable in accuracy to the level of assessment available in a professional sport setting,” while the test could be added to current head injury evaluation protocols at the elite level,” they add.
And as the biology of concussion is still not fully understood, sncRNAs might help to shed light on the response to injury as this evolves over time, they suggest.
“The detection of signatures of concussion at early time points in saliva (a non-invasively sampled biofluid) presents both at the pitch side, and in primary care and emergency medicine departments, an opportunity to develop a new and objective diagnostic tool for this common clinical presentation,” they conclude.
As an addendum to their findings, they added: “A patented salivary concussion test is in the process of being commercialized as an over-the-counter test for elite male athletes.
“Meanwhile our research team aims to collect further samples from players in two elite men’s rugby competitions to provide additional data to expand the test and develop its use. This will guide the prognosis and safe return to play after concussion and further establish how the test will work alongside the head injury assessment process.”
The researchers plan to add more participants to the SCRUM study, such as female athletes and community players. Source: Medical Xpress
Journal information: Valentina Di Pietro et al. Unique diagnostic signatures of concussion in the saliva of male athletes: the Study of Concussion in Rugby Union through MicroRNAs (SCRUM), British Journal of Sports Medicine (2021). DOI: 10.1136/bjsports-2020-103274
