Archive for the ‘Head Injury’ Category

Researchers at The University of Auckland have shown for the first time that the mere presence of carbohydrate solution in the mouth immediately boosts muscle strength, even before it is swallowed.

The results suggest that a previously unknown neural pathway is activated when receptors in the mouth detect carbohydrate, stimulating parts of the brain that control muscle activity and producing an increase in muscle strength.

Previous research had shown that the presence of carbohydrate in the mouth can improve physical performance during prolonged activity, but the mechanism involved was not known and it was unclear whether a person must be fatigued for the effect to be seen.

“There appears to be a pathway in the brain that tells our muscles when energy is on the way,” says lead researcher Dr Nicholas Gant from the Department of Sport and Exercise Science.

“We have shown that carbohydrate in the mouth produces an immediate increase in neural drive to both fresh and fatigued muscle and that the size of the effect is unrelated to the amount of glucose in the blood or the extent of fatigue.”

The current research has been published in the journal Brain Research and has also captured the attention of New Scientist magazine.

In the first of two experiments, 16 healthy young men who had been doing biceps exercises for 11 minutes were given a carbohydrate solution to drink or an identically flavored energy-free placebo. Their biceps strength was measured before and immediately afterward, as was the activity of the brain pathway known to supply the biceps.

Around one second after swallowing the drink, neural activity increased by 30 percent and muscle strength two percent, with the effect lasting for around three minutes. The response was not related to the amount of glucose in the bloodstream or how fatigued the participants were.

“It might not sound like much, but a two percent increase in muscle strength is enormous, especially at the elite level. It’s the difference between winning an Olympic medal or not,” says co-author Dr Cathy Stinear.

As might be expected, a second boost in muscle strength was observed after 10 minutes when carbohydrate reached the bloodstream and muscles through digestion, but no additional boost in neural activity was seen at that time.

“Two quite distinct mechanisms are involved,” says Dr Stinear. “The first is the signal from the mouth via the brain that energy is about to be available and the second is when the carbohydrate actually reaches the muscles and provides that energy,” says Dr Stinear.

“The carbohydrate and placebo solutions used in the experiment were of identical flavor and sweetness, confirming that receptors in the mouth can process other sensory information aside from the basic taste qualities of food. The results suggest that detecting energy may be a sixth taste sense in humans,” says Dr Gant.

In the second experiment, 17 participants who had not been doing exercise and were not fatigued simply held one of the solutions in their mouths without swallowing. Measurements of the muscle between the thumb and index finger were taken while the muscle was either relaxed or active.

A similar, though smaller effect was observed as in the first experiment, with a nine percent increase in neural activity produced by the carbohydrate solution compared with placebo. This showed that the response is seen in both large powerful muscles and in smaller muscles responsible for fine hand movements.

“Together the results show that carbohydrate in the mouth activates the neural pathway whether or not muscles are fatigued. We were surprised by this, because we had expected that the response would be part of the brain’s sophisticated system for monitoring energy levels during exercise,” says Dr Stinear.

“Seeing the same effect in fresh muscle suggests that it’s more of a simple reflex – part of our basic wiring – and it appears that very ancient parts of the brain such as the brainstem are involved. Reflexive movements in response to touch, vision and hearing are well known but this is the first time that a reflex linking taste and muscle activity has been described,” she says.

Further research is required to determine the precise mechanisms involved and to learn more about the size of the effect on fresh versus fatigued muscle.

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Article adapted by MD Sports from original press release.
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Contact: Pauline Curtis
The University of Auckland

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Concussions can happen to any athlete—male or female—in any sport. Concussions are a type of traumatic brain injury (TBI), caused by a blow or jolt to the head that can range from mild to severe and can disrupt the way the brain normally works.  

  • A concussion can occur when an athlete receives a traumatic force to the head or upper body that causes the brain to shake inside of the skull.  The injury is defined as a concussion when it causes a change in mental status such as loss of consciousness, amnesia, disorientation, confusion or mental fogginess.
  • Between 1.4 and 3.6 million sports and recreation-related concussions occur each year, with the majority happening at the high school level, according to the Center for Disease Control and Prevention.  Because many mild concussions go undiagnosed and unreported, it is difficult to estimate the rate of concussion in any sport, but studies estimate that at least 10 to 20 percent of all athletes involved in contact sports have a concussion each season
  • Because no two concussions are exactly alike and symptoms are not always definite, the injury’s severity, effects and recovery are sometimes difficult to determine.  The decision to allow the athlete to return to the game is not always straightforward, although research has shown that until a concussed brain is completely healed, the brain is likely vulnerable to further injury.  Thus, the critical importance of properly managing the injury.
  • Allowing enough healing and recovery time following a concussion is crucial in preventing any further damage. Research shows that the effects of repeated concussion in young athletes are cumulative. Most athletes who experience an initial concussion can recover completely as long as they are not returned to contact sports too soon. Following a concussion, there is a period of change in brain function that varies in severity and length with each individual. During this time, the brain is vulnerable to more severe or permanent injury. If the athlete sustains a second concussion during this time period, the risk of more serious brain injury increases.
  • In recent years, research has shown that even seemingly mild concussions can have serious consequences in young athletes if they are not properly managed. Loss of consciousness is not an indicator of injury severity. Traditional imaging techniques such as MRI and CT may be helpful in severe injury cases, but cannot identify subtle effects believed to occur in mild concussion. 
  • An explosion of scientific research over the past decade has taught doctors more about the proper management of sports-related concussion than was ever known before, and has raised public awareness and significantly changed the way sports concussions are managed.
  • Much of the recently published research includes data proving the usefulness of objective neurocognitive testing, such as ImPACT™, as part of the comprehensive clinical evaluation to determine recovery following concussion.  Recent international sports injury management guidelines have emphasized player symptoms and neuropsychological test results as “cornerstones” of the evaluation and management process.

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Article adapted by MD Sports Weblog from original press release.
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Contact: Susan Manko
University of Pittsburgh Schools of the Health Sciences

Concussions are common in young athletes but the underlying changes in brain function that occur have been poorly understood. Now, a University of Pittsburgh School of Medicine study is the first to link changes in brain function directly to the recovery of the athlete. Results of the five-year study, funded by the National Institutes of Health, are published in the August issue of the scientific peer-reviewed journal, Neurosurgery, the official journal of the Congress of Neurological Surgeons.

“We found that abnormal brain activity in children and adolescents on functional MRI (fMRI) was clearly related to their performance on neuropsychological tests of attention and memory and to their report of symptoms such as headaches,” said principal investigator Mark Lovell, Ph.D., asssociate professor in the departments of orthopaedic surgery and neurological surgery at the University of Pittsburgh School of Medicine.

“These results confirm crucial objective information that is commonly obtained by neuropsychological testing to help team doctors and athletic trainers make critical decisions about concussion management and safe return to play,” added Dr. Lovell, who is founding director of the University of Pittsburgh Medical Center (UPMC) Sports Medicine Concussion Program, a clinical service and research program focused on the management of sports-related concussions.

“Our findings have several implications for understanding the recovery process after sports-related concussions,” said study co-author Michael (Micky) Collins, Ph.D., assistant professor in the departments of orthopaedic surgery and neurological surgery at Pitt’s School of Medicine, and assistant director of the UPMC program. “Although the results of this study must be considered preliminary, fMRI represents an important evolving technology that is providing further insight now for safe return-to-play decisions in young athletes and may help shape guidelines in the future.”

The study helps define concussion and recovery for safe return-to-play

According to the Centers for Disease Control and Prevention, between 1.4 and 3.6 million sports and recreation-related concussions occur each year, with the majority happening at the high school level. “An explosion of scientific research over the past decade has taught us more about mild traumatic brain injury or concussion than we have ever known,” noted Dr. Lovell, “including the knowledge that mismanagement of even seemingly mild concussions can lead to serious consequences in young athletes.”

A concussion can occur when an athlete receives a traumatic force to the head or upper body that causes the brain to shake inside of the skull. Injury is defined as a concussion when it causes a change in mental status such as loss of consciousness, amnesia, disorientation, confusion or mental fogginess. The severity, effects and recovery of concussion are difficult to determine because no two concussions are alike, and symptoms are not always straightforward. In recent years, research has shown that until a concussed brain is completely healed, the brain may be vulnerable to further injury, which has led to published studies that have raised public awareness and significantly changed the way sports concussions are managed. Importantly, much of this research has included data that proves the usefulness of objective neuropsychological test data as part of the comprehensive clinical evaluation to determine clinical recovery following concussion. In fact, recent international concussion management guidelines have emphasized player symptoms and neuropsychological test results as “cornerstones” of the injury evaluation and management process.

While neuropsychological testing has become an increasingly useful tool, no published studies have examined the relationship between changes in computerized neuropsychological testing completed in a medical clinic and brain function as measured by fMRI. The lack of studies using fMRI may be due to the fact that studies of this nature are very expensive and equipment necessary to undertake this research is not readily available outside of a handful of academic medical centers. UPMC is one of few such centers with the capability of collecting both neurophysiological (fMRI) and neuropsychological data from injured and clinically managed athletes. fMRI is one of the few brain scanning tools that can show brain activity, not just the anatomy. Traditional brain scanning techniques such as MRI and CT are helpful in viewing changes to the brain anatomy in more severe cases, but cannot identify subtle brain-related changes that are believed to occur on a metabolic rather than an anatomic level. fMRI can determine, through measurement of cerebral blood flow and metabolic changes, which parts of the brain are activated in response to different cognitive activities.

fMRI reveals preliminary evidence and lays ground work for future research

“In our study, using fMRI, we demonstrate that the functioning of a network of brain regions is significantly associated with both the severity of concussion symptoms and time to recover,” said Jamie Pardini, Ph.D., a neuropsychologist on the clinical and research staff of the UPMC concussion program and co-author of the study. The study documented the link between changes in brain activation and clinical recovery in concussed athletes, which was defined as a complete resolution of symptoms and neuropsychological testing results that appeared within expected levels or back to the athlete’s personal baseline. “It is our view that studies establishing a link between brain physiology and neuropsychological testing help demonstrate the utility of neuropsychological testing as a proxy for direct measurement of brain functioning after concussion,” Dr. Pardini added.

The research project involved 28 concussed high school athletes and 13 age-matched controls. The concussed athletes underwent fMRI evaluation within approximately one week of injury and then again when they met criteria for clinical recovery. During their fMRI exams, the athletes were given working memory tasks to complete while the brain’s activity was observed and recorded. As a group, athletes who demonstrated the greatest degree of hyperactivation at the time of their first fMRI scan also demonstrated a more prolonged clinical recovery than did athletes who demonstrated less hyperactivation during their first fMRI scan. “We identified networks of brain regions where changes in functional activation were associated with performance on computerized neuropsychological testing and certain post-concussion symptoms,” reported Dr. Pardini. “Also, our study confirms previous research suggesting that there are neurophysiological abnormalities that can be measured even after a seemingly mild concussion,” she added. The study utilized a computer-based neuropsychological test called ImPACT™ (Immediate Post-Concussion and Cognitive Testing), which measures cognitive function such as attention, memory, speed of response and decision making. ImPACT was developed by Dr. Lovell and colleagues over the past decade and has been extensively researched by the University of Pittsburgh and other academic institutions throughout the world. Drs. Lovell and Collins have a proprietary interest in the ImPACT test as does UPMC. ImPACT Applications, Inc., is a Pittsburgh-based company that owns and licenses the ImPACT tool.

“Recent years have marked exciting and important discoveries in sports concussion research but there are still many unanswered questions,” said Dr. Lovell. “Continued research designed to evaluate multiple parameters of concussion effects and recovery will further help structure return-to-play guidelines.”

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Article adapted by MD Sports Weblog from original press release.
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Contact: Susan Manko
University of Pittsburgh Schools of the Health Sciences

Other authors of the study include James Becker, Ph.D., of the University of Pittsburgh; Joel Welling, Ph.D., Jennifer Bakal and William Eddy, Ph.D., of Carnegie-Mellon University; Nicole Lazar, Ph.D., of the University of Georgia, Athens, Ga.; and Rebecca Roush, Psychology Software Tools, Pittsburgh. The study was funded by a $3 million grant from the National Institutes of Health.

A player just took a hard knock to the head and is lying on the field. A coach rushes to his side, but the player sits up and seems fine.He knows who the president is and how many fingers the coach is holding up. But is he ready to get back in the game?

More than 750,000 mild traumatic brain injuries (mTBI) occur in the United States each year. When a player or soldier with even a mild concussion is sent back to the field, another blow to the head can lead to additional life long problems or even second impact syndrome, which has a mortality rate of up to 50 percent. But the injury is difficult to diagnose, even with a quiet room and a several-hour-long test.

Michelle LaPlaca, an assistant professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University, and David Wright, assistant director of Emory University’s Emergency Medicine Research Center, have developed a new device to detect brain injuries right on the sidelines of a football game, on a battlefield or in the emergency room.

Called DETECT (Display Enhanced Testing for Concussions and mTBI system), the device is a fast, easy to administer and sensitive system for assessing problems associated with concussions. The DETECT device is an integrated system that includes software applications, a portable computer and an LCD display in the headgear.

While a typical mTBI test requires a quiet room and 1-2 hours of testing, DETECT performs neuropsychological tests in an immersive environment in about 7 minutes, regardless of surrounding noise and movement. So, a football player or soldier who just took a hard hit to the head can take the test and either be safely cleared to get back on the field or sent to receive medical attention.

The device blocks external stimuli that could interfere with testing, such as light and sound. This allows the test to be given in virtually any setting, even a bright football field with a roaring crowd.

When suffering from mTBI, a person will have difficulty with certain types of thinking controlled by a different areas of the brain, such as working memory, complex reaction and multi-tasking. DETECT runs the wearer through three types of neuropsychological tests that measure the function of several parts of the brain as it attempts to perform the tests.

For example, the first shows the wearer a series of shapes with different colors and textures and gives voice instructions. The wearer uses a simple controller (similar to a video game controller) to respond to the commands. The device then measures the wearer’s response times and answer selections. If the response time is too slow or the incorrect answers were provided, it indicates impairment.

The DETECT system includes a laptop to run the software, a head-mounted display, earmuffs that also act as headphones and an input device (controller). The display projects the visual aspect of the test, the headphones provide the verbal instructions and the controller records the wearer’s response.

In addition to the advantages of its speed and portability, DETECT can also be administered by a non-medical personnel such as a coach or parent rather than a trained neurophysiologist.

While the device has already been tested in the lab and in a hospital emergency room, the Georgia Tech football program recognizes the need for improved concussion assessment and plans to test this new technology.

DETECT may have other potential cognitive testing applications, such as helping assess cognitive impairment related to Alzheimer’s disease or drug use. The test would be brief and could be performed in a general physician’s office.

DETECT is expected to be commercially available in the next three to five years.

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Article adapted by MD Sports Weblog from original press release.
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Contact: Megan McRainey
Georgia Institute of Technology

Football players who suffer the dangerous head injury known as concussion are three times more likely than other players to suffer a second concussion in the same season, according to a new University of North Carolina at Chapel Hill study.The study, published in the September-October issue of the American Journal of Sports Medicine, suggests that the brain is more susceptible to injury when it has not had enough time to recover from a first injury. Researchers say the finding is important because concussions can lead to permanent brain damage, vision impairment or even death if not managed properly.

“We believe recurrences are more likely because injured players are returning to practice and to games too quickly after blows to the head,” said Dr. Kevin M. Guskiewicz, assistant professor of exercise and sport science at UNC-CH and study leader. “Many clinicians are not following the medical guidelines that players should be symptom-free for several days before returning.”

Guskiewicz directs the Sports Medicine Research Laboratory and the Undergraduate Athletic Training Education Program, both at UNC-CH. Co-authors of the new paper are Nancy L. Weaver, research associate for the N.C. High School Injury Surveillance Program; Darin A. Padua, doctoral student in sports medicine at the University of Virginia; and Dr. William E. Garrett Jr., professor and chair of orthopaedics at the UNC-CH School of Medicine.

For three years, the researchers surveyed a random sample of 242 certified athletic trainers across the United States who worked with high school and college football teams. More than 17,500 football players were represented in the study, which covered 1995 to 1997. About 5 percent suffered concussions each year. Researchers also conducted telephone interviews with a smaller group.

“We wanted to learn more about concussions — the incidence of injury, the mechanism of injury and whether players seemed to be injured more frequently on artificial turf than on grass,” Guskiewicz said. “We found the incidence of injury to be highest at the high school and Division III level, while Division I and II college players suffered fewer concussive injuries.”

Possible explanations include poorer quality and fit of protective equipment, he said. Another possibility is that college players are more skilled on average, and better players are known to be less susceptible to injury.

The UNC-CH professor and colleagues found that 31 percent of athletes with concussions began playing again the same day they were injured.

“This didn’t surprise us, but it does worry us,” Guskiewicz said. “Eighty-six percent of players reported having at least a headache after the incident, and you should never return to play with a headache. It was probably all right for the 14 percent of players with no symptoms to return.”

Artificial turf didn’t produce more head injuries than natural grass, the researchers found. Concussions on artificial turf, however, were more serious. Artificial athletic fields are sheets of synthetic grass over shock-absorbing pads stretched across concrete slabs.

Another key finding was that only one in 20 players suffered a concussion during the season rather than the one in five reported in 1983. Almost 15 percent of injured players suffered a second concussion in the same season, and it tended to be more serious than the first. The most common symptoms were headache, dizziness and confusion.

“That earlier 20 percent figure appears to have been a gross over-estimation,” Guskiewicz said. “Still, the rules have changed to make the game safer and the equipment, especially helmets, are safer and have to be approved by the National Operating Committee on Standards in Athletic Equipment (NOCSAE). Also, many coaches are being smarter in limiting physical contact time in practices. They are stressing the importance of players keeping their heads up during blocking and tackling, not dropping their heads, which is against the newer rules and is much more dangerous.”

Defensive backs, offensive linemen and linebackers were the most frequently concussed players, but special team players and wide receivers were more likely to suffer more serious concussions. During the 1999 season, all six U.S. high school players killed as a direct result of football accidents died from injuries to their brains, according to a different UNC-CH study released in August.

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Article adapted by MD Sports Weblog from original press release.
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Contact: David Williamson
University of North Carolina at Chapel Hill

Sports medicine specialists in the University at Buffalo’s Sports Medicine Institute have developed a new method for treating athletes who sustain post-concussion syndrome that, unlike the conventional approach, allows athletes to maintain conditioning while recovering gradually from the injury.

For unknown reasons, 5-10 percent of people who experience a concussion have symptoms that persist beyond six weeks. These people are diagnosed with post-concussion syndrome (PCS). Previously there has been no treatment for the condition with proven success.

“The most common approach by physicians is to recommend no exercise and prescribe antidepressants,” said Barry Willer, Ph.D., UB professor of psychiatry and rehabilitation sciences. Willer is lead author on the paper describing the new method, published in the September issue of Current Treatment Options in Neurology.

“Most people with PCS have symptoms of depression,” said Willer, “so anti-depressant treatment makes sense. However, antidepressants do little more than relieve some of the depression symptoms. We were interested in a treatment that didn’t just treat the symptoms, but actually improved the patient’s brain function.”

The researchers call their new treatment “regulated exercise.” The approach consists of determining the ideal exercise program for each athlete based on a number of individual physiological indicators at baseline.

Patients are tested every two to three weeks with specialized equipment at the sports medicine clinic to determine their progress, and a new program is developed based on those results.

Willer and co-author John Leddy, M.D., clinical associate professor of orthopaedics and rehabilitation sciences, indicated it is too early to call the treatment a cure, but they are optimistic about the results so far.

The researchers described the treatment method in mid-September at the 2006 Brain Injury Conference of the Americas in Miami, where the response was very favorable, according to Willer.

“Professionals at the meeting were delighted that our approach to treatment of post-concussion syndrome doesn’t involve any medications and is very cost-efficient. We were surprised to learn that we are among only a few investigators interested in people with symptoms that won’t go away.

“There is no other known treatment specifically for PCS, which we define as persistent symptoms of concussion past the time they should have cleared, usually around three weeks,” said Willer. “As far as we can determine, there is only one other group in North America that is using regulated exercise as part of the treatment for PCS.”

Willer and Leddy have used regulated exercise successfully with people who were as much as six months post-concussion. Their regimen is based on the hypothesis that the regulatory system responsible for maintaining cerebral blood flow, which may be dysfunctional in people with a concussion, can be restored to normal by controlled, graded symptom-free exercise.

“The treatment program is well tolerated by patients” Willer said. “Just being able to exercise often reduces the depressive symptoms. But it’s imperative that the patient not go beyond the exercise limits.

“After the first three weeks of regulated exercise, we reassess the patient to see if there has been any change in physiology. The exercise program then is realigned successively to respond to the changes. In our experience thus far, symptoms disappear within several months for at least some of the patients,” he said.

The specialists have worked with a small number of patients to date. They have included a UB soccer player who has returned to play and now is one of the team’s leading scorers. Another young athlete was able to return to cross-country running and attend school full-time.

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Article adapted by MD Sports Weblog from original press release.
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Contact: Lois Baker
University at Buffalo