April 01, 2014
16 min read

Residual problems of concussions have helped raise awareness of symptoms, treatment

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Each year, 1.7 million people in the United States sustain a traumatic brain injury, according to the Centers for Disease Control and Prevention. Of these, roughly 75% to 90% are characterized as “mild” traumatic brain injuries, or concussions. While these injuries are classified as mild, they can cause significant lifelong impairment.

A concussion is “a traumatically induced brain injury that produces either an alteration in level of consciousness or one of more than 22 post-concussion symptoms,” Robert C. Cantu, MD, a clinical professor of neurosurgery at Boston University School of Medicine, told Spine Surgery Today.

Typically, concussions are caused by a jolt to the head, a fall, or a blow to the body that causes the head and brain to snap back and forth. A concussion causes physical, cognitive, emotional and/or sleep-related symptoms that include headache, nausea, vomiting, balance problems, mental fogginess, fatigue and irritability.

For years, people viewed concussions as a relatively insignificant problem. But as researchers learned more about the potential long-term effects of concussion, that view changed.

The future in concussion diagnosis, according to Robert C. Cantu, MD, may involve tracking the presence of a specific biomarker for the condition.

The future in concussion diagnosis, according to Robert C. Cantu, MD, may involve tracking the presence of a specific biomarker for the condition.

Image: Rob Carlin Photography

“There has been a major cultural shift in how concussions and concussed patients are seen,” said Joseph C. Maroon, MD, FACS, a professor and Vice Chairman of the Department of Neurosurgery and the Heindl Scholar in Neuroscience at the University of Pittsburgh Medical Center. “We have become much more aware that there can be virtually devastating types of residual problems from seemingly minor blows to the head,” he said.

That shift in thinking began in 2005, when Bennett Omalu, MD, a neuropathologist at the University of Pittsburgh, published the results of an autopsy and neuropathological evaluation of the brain of retired National Football League (NFL) player Mike Webster, Maroon said.

Joseph C. Maroon

Joseph C. Maroon

“In [Webster’s] brain, [Omalu] described abnormalities usually associated with profound neurodegenerative diseases such as Alzheimer’s,” said Maroon, who is a member of the Spine Surgery Today Editorial Board.

These abnormalities were later identified as chronic traumatic encephalopathy (CTE), which results from repetitive blows to the head. “The fear and the awareness of potential, progressive neurodegenerative disease following concussion has given everyone a heightened awareness of the potential long-term effects of blows to the head and concussions,” Maroon said.

CTE is not the only threat from repeated concussions and there are many cumulative effects of concussion. Other research has linked mild traumatic brain injury to depression in teenagers and retired NFL players, while another study demonstrated a relationship between concussion history and the risk of Alzheimer’s disease.

Failure to report symptoms

Despite the increased awareness, under-reporting continues to be a problem.

“There is still a reluctance on the part of the athletes to actually report injuries because of their concerns about not being able to play,” David A. Wong, MD, MSc, FRCS, director of the Advanced Center for Spinal Microsurgery, Presbyterian St. Luke’s Medical Center, in Denver, said. Wong is a member of the Spine Surgery Today Editorial Board.

According to a 2013 Institute of Medicine (IOM) report, this reluctance is due to a “culture of resistance” in sports, which negatively influences athletes’ self-reporting of symptoms as well as their adherence to return-to-play guidelines.

“If the youth sports community can adopt the belief that concussions are serious injuries and emphasize care for players with concussions until they are fully recovered, then the culture in which these athletes perform and compete will become much safer,” the authors of the IOM report wrote.


As part of a multidisciplinary team, neurosurgeons and orthopedic spine surgeons can play an important role in ensuring that concussed patients get appropriate, well-timed treatment.

First step: Neurologic assessment

The first step in diagnosing a concussion is a neurologic assessment, which is focused on the patient’s level of alertness. Its goal is to identify confusion, amnesia or other problems with mental function in the patient, according to Cantu. This assessment should also evaluate the patient’s balance, behavior and mood symptoms, he said.

Several tools are available for neurologic evaluation. For athletes, one option is the Sport Concussion Assessment Tool – 3rd edition (SCAT3), which is a standardized tool used to assess athletes aged 13 years and older for concussions on the sidelines. The CDC also has an Acute Concussion Evaluation form that works much like the SCAT3.

Smartphone apps can help evaluate concussions. Last year, the American Academy of Neurology launched “Concussion QuickCheck” to help coaches, trainers, parents and athletes assess whether someone has a concussion and requires additional care.

Maroon and colleagues developed an iPhone app called Sideline ImPACT for balance testing.

“You literally put your iPhone on the individual’s chest and [perform] a sway balance test,” Maroon said.

Computerized neurocognitive testing

Another tool to help diagnose concussions is computerized neurocognitive testing. “[This type of testing] provides valuable information in order to assist clinicians in making return-to-play decisions, but also for recognizing the significance of the injury,” Jacob E. Resch, PhD, ATC, professor of kinesiology and director of the Brain Injury Laboratory at the University of Texas at Arlington, said.

Resch recommends using computerized neurocognitive testing at three time points: baseline, 24 hours to 72 hours after injury, and again once the patient has been symptom-free for 24 hours.

Jacob E. Resch

Jacob E. Resch

And, although most of the programs were developed specifically for sports, there is an opportunity to apply them to non-athlete populations, Resch told Spine Surgery Today.

The one downside that experts see to this is there is no baseline evaluation for non-athletes. Therefore, post-injury test results must be compared with normative values, which may be slightly misleading.

“If somebody is brilliant and has an IQ upwards of 130 or higher, when they are baselined, they are going to score way higher than the normative value,” Cantu said. “That person, when impaired significantly, could still score higher than the normative value or well into the normal range. And yet, they are very impaired for them.”

The most well-known computerized neurocognitive test is ImPACT, which Maroon and Mark Lovell, PhD, pioneered at the University of Pittsburgh.

“We have now evaluated and baselined over 5 million kids with this test,” Maroon said.

If a child sustains a concussion, data from their post-injury test is compared with the pre-injury to determine severity, he noted.

“For the first time, we have objective data to determine the processing information — the memory, the reaction time of the brain — to make objective decisions,” Maroon said.

Other computerized tests include the Headminder, CogSport and Automated Neuropsychological Assessment Metrics (ANAM) tests.

Computerized neurocognitive testing offers benefits compared with traditional pencil-and-paper neurocognitive testing. It is quick — assessment can be performed in 20 minutes to 25 minutes compared with the 5 hours to 6 hours needed for pencil-and-paper testing. Administration is standardized, and the test can be administered individually or to small groups of athletes, which makes it more efficient to use, Resch said.


However, these tests have some limitations and they are expensive. In addition, although these tests are widely used, there are limited data that support their reliability.

“We recently just completed a review of psychometric properties of neurocognitive tests, such as reliability, validity; we found that it is somewhat limited,” Resch said.


The results of the review showed that the ImPACT test misidentified healthy participants as impaired in some cases up to 46% of the time, which underscores the need to use multiple measures to evaluate patients for concussion.

In addition, computerized neurocognitive tests are going to miss patients who have balance issues or visual issues because they are only examining the cognitive issues.

“If that is the only test you use, you are going to miss people who are still symptomatic,” Cantu said.

Maroon told Spine Surgery Today, “My colleagues and I find it difficult to understand the results of Resch relative to misidentification of healthy patients. In direct contradistinction to his results are those recently reported by Schatz and Sandel in the February 2013 issue of American Journal of Sports Medicine. These authors found an extremely high degree of reliability, sensitivity and specificity with the ImPACT test. They evaluated asymptomatic athletes within a week postinjury (all athletes had been previously diagnosed with an on-field injury, but claimed to be symptom free within 3 days). ImPACT showed a 94% sensitivity and 97% specificity when compared to noninjured controls. Also, there are many other reliability studies which show completely acceptable test-retest stability with ImPACT scores. In short, there is extensive research supporting the reliability, validity, sensitivity, specificity and added value of ImPACT in evaluating sports-related concussions which Resch and colleagues, for whatever reason, appear to have overlooked.”

Imaging technologies lacking

The next step in diagnosis is to use imaging to determine if there is any damage to the brain. However, current imaging technologies such as the standard CAT scan and MRI are unable to detect the subtle damage associated with concussions.

“The standard CAT scan and the standard MRI do not have the resolution at the microscopic level, therefore, they will be normal with a concussion,” Cantu said. “They are used to rule out bleeding, primarily.”

“There actually is damage at the microscopic level with some concussions,” he said. “We know that from individuals who have unfortunately committed suicide shortly after a concussion and their brains were studied microscopically. Diffuse axonal swelling was been seen.”

New, more sophisticated imaging technologies have shown some promise, according to Cantu.

In-depth look at impairment

The functional MRI is a metabolic study in which the patient performs a cognitive task while in the scanner. The specific part of the brain that is being accessed will light up as he or she becomes more metabolically active, he said.

“What you are looking for is decreased uptake, hypometabolism, reflective of impairment of brain function,” Cantu said.

Diffusion tensor imaging (DTI) is an MRI study that examines fractional anisotropy, Cantu said. DTI looks at fiber tracks in the brain and whether those fiber tracks are intact and parallel.

“If you have a concussion or other brain injury, there may be an increase in this fractional anisotropy and it is reflective of a disruption of fiber tracks,” Cantu said.

High-definition fiber tracking also follows fiber tracks, but with a higher resolution scanner, he said.

Magnetic spectroscopy MRI studies break-down products and identifies when the relative ratios are out of alignment, indicating a brain injury, Cantu said.

None of these imaging tools are “prime-time clinical tools,” he said. DTI, which is being used in a select number of institutions right now, is the closest to consistent clinical use. “I bet within the next year or two, it will be used more widely in a clinical setting,” Cantu said.

Treatment and prognosis

Once the diagnosis is confirmed, concussion treatment is simple and consists of a week or two of physical and cognitive rest.

“The first thing you do is shut down the engine,” Maroon said. “Turn off the motor. Go into a dark room. Don’t use your TV. Don’t use your brain. Rest and let nature heal the brain.”


The prognosis for concussed patients is usually good. About 80% of patients recover from their injury without incident within 7 days to 14 days, Cantu said.

But some patients — about 15% to 20% of them — have persistent concussive symptoms that extend beyond 14 days, which is called post-concussion syndrome. For these patients, there are several other treatment options and the ones used depend on the symptom cluster the person displays, Cantu said.

If the patient has primarily cognitive issues, then cognitive therapy can be employed, which involves memory exercises and tests. The patient learns coping skills such as taking notes and recording classroom lectures to help with recall, Cantu said.

Vestibular physical therapy can help patients who have balance issues, lightheadedness or equilibrium problems. Physical therapy targeted to the upper cervical spine can help patients who continue to suffer headaches and neck stiffness, he said.

If these therapies are not successful, medications are an option, according to Cantu.

“I personally think they should be used last,” he said, noting the methylphenidate class of medications can help with cognitive problems, antidepressants, like escitalopram oxalate (Lexapro; Forest Laboratories) can treat lingering mood and behavioral issues. Meclizine or meclizine hydrochloride or Bonine can help with vestibular symptoms.

Maroon has had good results using nutraceuticals such as omega-3 fatty acids, fish oil, magnesium, vitamin D3 and resveratrol, which are natural anti-inflammatories.

According to Maroon and colleagues, the process of concussion is linked to neuroinflammation.

“It is like getting a splinter under your finger nail,” he said. “It gets red, hot, tender and swollen due to the body’s natural immune system. The same thing happens in the brain we think, modulated by microglia, the cells in the brain responsible for the immunological reaction that occurs in the brain.”

These natural inflammatories may have some therapeutic benefit; however, more research is needed to confirm that concept.

“But there is no downside to using those at the present time,” Maroon said.

Prevention is crucial

Given the substantial sequelae associated with concussions, the primary focus should be on prevention. Intelligent mouth guards, which measure impact, may help researchers design equipment that is safer and more protective, which may ultimately reduce the number of TBIs in athletes.

“These strategies use accelerometers in the mouth guard that detect the extent of impact,” Edward C. Benzel, MD, who is chairman of the department of neurosurgery at the Cleveland Clinic, in Cleveland, said. “We are beginning to study this in boxers, and we have already studied it preliminarily in high school ice hockey players and in football players.”

Benzel and colleagues designed a mouth guard with tiny sensors that measure head orientation, position, velocity and acceleration of impact. Using Bluetooth technology, the data are wirelessly transmitted to a computer on the sideline.

Edward C. Benzel

Edward C. Benzel

“We believe our strategy is very scientific and focuses on much more than just linear acceleration,” Benzel told Spine Surgery Today. “It focuses on the rotational component. We focus also on the translation of that information to the center of gravity in the brain,” he said.

Researchers and designers should continue to work on protective headgear, especially football helmets. Although modern hard-shell helmets prevent catastrophic injuries, they may not be as effective against concussions, according to Benzel.

He and colleagues compared the head impact doses and injury risks of 21st century varsity helmets with 20th century leatherheads.

“We demonstrated that in near-concussive blows, around 50 gs to 60 gs, the circa 1920 to 1930 leatherhead helmet was equally effective at preventing injury,” Benzel said. “Modern varsity helmets were no more effective than the leatherhead.”


No-contact practice?

Clearly, football helmets nearly eliminate focal concussions.

“On the other hand, a concussion that occurs because your head was hit by someone else [who] had a rigid neck and 200 pounds of body behind it, your head is going to be finitely moved from the position it was in,” Cantu said. “Those rotational forces are very little dampened by helmets.”

The best way to lower concussion rates is to reduce the amount of trauma the head absorbs, Cantu said. Sixty percent to 70% of concussions and head trauma occur during practice. “If you take contact out of practice … you can greatly reduce the amount of trauma the brain sees, reduce the amount of concussive and subconcussive blows,” he said.

Sources for this article noted that the next phase of concussion research should focus on clearer guidelines.

“The next stage, which is very controversial, is how to classify the degree of concussion and have that translate into parameters like the recovery time and the ability to return to sports,” Wong said. “[We need] some clearer guidelines on how to classify the grades of concussion initially on the field.”

For example, do patients who have had a momentary loss of consciousness automatically require an MRI or CT scan of the head? “That is unclear from my perspective,” Wong said.

“Presently, concussion diagnosis uses many assessments, none of them alone more than 80% accurate but collectively highly accurate. The future for concussion research will involve identifying a single, highly sensitive and specific biomarker of concussion injury and when it has cleared,” Cantu said. – by Colleen Owens

Bartsch A. J Neurosurg. 2012. doi:10.3171/2011.12.JNS111478.
Blaylock RL. Surg Neurol Int. 2011. doi:10.4103/2152-7806.83391.
Centers for Disease Control and Prevention. Heads up: Facts for Physicians About Mild Traumatic Brain Injury. Retrieved from http://www.cdc.gov/concussion/headsup/pdf/facts_for_physicians_booklet-a.pdf.
Centers for Disease Control and Prevention. Injury Prevention and Control: Traumatic Brain Injury. Retrieved from http://www.cdc.gov/traumaticbraininjury/.
McCrory P. Br J Sports Med. 2013. doi:10.1136/bjsports-2013-092313.
Resch J. J Athl Train. 2013. doi:10.4085/1062-6050-48.3.09. Epub 2013 May 31.
For more information:
Edward C. Benzel, MD, can be reached at Cleveland Clinic Main Campus, Mail Code S40, 9500 Euclid Ave., Cleveland, OH 44195; email: benzele@ccf.org.
Robert C. Cantu, MD, can be reached at the Center for the Study of Traumatic Encephalopathy, Boston University School of Medicine, 131 Old Road to Nine Acre Corner, Concord, MA 01742; email: rcantu@emersonhosp.org.
Joseph C. Maroon, MD, FACS, can be reached at the University of Pittsburgh Medical Center, 200 Lothrop St., Pittsburgh, PA 15213; email: maroonjc@upmc.edu.
Jacob E. Resch, PhD, ATC, can be reached at the Department of Kinesiology, University of Texas at Arlington, 113 Maverick Activities Center, Box 19259, Arlington, TX 76019-0259; email: resch@uta.edu.
David A. Wong, MD, MSc, FRCS, can be reached at Denver Spine Surgeons, 7800 East Orchard Rd., Suite 100, Greenwood Village, CO 80111; email: ddaw@denverspine.com.
Disclosures: Benzel has a vested interest in the development of an accelerometer-based mouth guard for the assessment of head injury during contact sports. Cantu is senior advisor NFL Head Neck Spine Committee, vice president of NOCSAE and chair scientific advisory committee-founder, chair medical advisory board, medical director SLI, receives royalties from Houghton Mifflin Harcourt, and is an expert witness. Maroon is co-founder of ImPACT. Resch has been a paid consultant to Pearson. Wong has no relevant financial disclosures.


What is the best approach to assess and manage patients with persistent post-concussive symptoms (more than 10 days)?


Focus on specific signs, symptoms

Approximately 10% of patients who experience a concussion will develop post-concussive syndrome, the symptoms of which include subjective complaints of headache, dizziness, lightheadedness, nausea, concentration difficulties, memory loss, irritability, depression, anxiety, sleepiness and others. These symptoms can last for days, months, even a year after concussion. The etiology of the post-concussive symptoms included oculovestibular dysfunction, musculoskeletal injury, sleep disorder, dehydration, external emotional stressors and others. Underlying psychological disorders may be present as well.

William C. Welch

William C. Welch

The assessment of patients with post-concussive symptoms includes obtaining a focused history (with careful attention to the patient’s descriptors of the headaches) and physical examination. The latter should include detailed assessments of the cranial nerves, vestibular function, neurocognitive function and cerebellar integrity. Balance needs to be carefully assessed.


Treatment is directed toward specific signs and symptoms. For example, tricyclic antidepressants may be required for patients with sleep dysfunction following a concussion. Physical medicine and rehabilitation can be considered for patients with oculovestibular findings or musculoskeletal disorders. Correction of sleep disorders and avoidance/reduction in emotional stressors should also be strongly considered.

William C. Welch, MD, FAANS, FACS, FICS, is Professor and Clinical Vice Chairman of Neurosurgery at the University of Pennsylvania School of Medicine, is Chief of Neurosurgery at Pennsylvania Hospital in Philadelphia and is a Spine Surgery Today Editorial Board member.
Disclosure: Welch has no relevant financial disclosures.


Consider cervical pathology

A minority of concussion patients have symptoms that persist for more than 10 days. These can often overlap and be confused with other abnormalities such as depression and anxiety. Referral to a health care professional with a special interest in concussion management should be considered. Likewise, imaging (MRI preferably) and neurocognitive testing are often employed at this time. Psychosocial evaluation is helpful in evaluating the patient’s support system, mental health history, comorbid conditions and change in social status. While an individual’s symptoms and treatment are quite variable, specific categories of dysfunction should be addressed in all. These include cervicogenic pathology, autonomic dysfunction, vestibular abnormalities, visual symptoms and cognitive/behavioral deficits.

Vincent J. Miele Jr.

Vincent J. Miele Jr.

Cervical pathology should be considered in patients with persistent symptoms, such as headache, dizziness and nausea. Cervicogenic headaches are usually unilateral and provoked by neck movements, prolonged postures or pressure on tender points. Assessment usually involves range of motion activities and provocative maneuvers. Treatment options vary from stretching/strengthening to biofeedback and acupuncture. Of note, post-traumatic headaches that are migrainous in nature are occasionally treated with migraine-specific abortant medications.

Symptoms of autonomic dysfunction can include an increased heart rate at rest and with exertion (including cognitive stress), changes in sympathetic and parasympathetic activity and disturbed cerebral autoregulation. Assessment includes measuring the patient’s heart rate response to positional changes and evaluating symptom exacerbation during activities that raise the heart rate. While rest is usually recommended immediately after a concussion, persistent autonomic symptoms are frequently treated using a progressive exercise program.

Abnormalities of the vestibular system (such as balance difficulties, dizziness and vertigo) are commonly reported following concussion. Both static and dynamic postural stability testing helps diagnosis dysfunction, as does provocative vestibulo-ocular reflex testing. Treatment consists of canalith repositioning, balance/gait exercises and vestibulo-ocular reflex activities.

Vision plays an important role in balance, gait, and other activities of daily living. Signs and symptoms include blurred vision, light sensitivity, peripheral vision restrictions, and poor depth perception. Abnormalities of the visual system can also exacerbate cognitive difficulties. Evaluation by a qualified optometrist/ophthalmologist specializing in neuro-optometric rehabilitation would be ideal in these patients. Treatment includes visual exercises such as tracking, pursuits, vestibular integration and vergence.


Finally, cognitive and behavioral abnormalities need to be addressed. Sleep disturbances, depression and anxiety are frequently reported and are often treated successfully with cognitive-behavioral therapy. First line pharmacological management usually consists of selective serotonin reuptake inhibitors. Non-resolving cognitive dysfunction should be referred for neuropsychological evaluation to define specific deficits and design a management strategy.

Most importantly, the patient should be protected from further trauma to the brain while still symptomatic and be reassured these symptoms almost always resolve within 3 months to 6 months.

Vincent J. Miele Jr., MD, FAANS, is a neurosurgeon at University of Pittsburgh Medical Center Passavant Hospital in Pittsburgh.

Disclosure: Miele has no relevant financial disclosures.


Treatment depends on the patient and their symptoms

Treatment of persistent post-concussive symptoms depends on the patient and their symptoms. There are often complicating factors in a patient’s background that may make them susceptible to lingering effects of concussion. Because we do not currently understand what those are, they are hard to predict. We cannot know well at baseline who is going to recover slowly or quickly, although having more symptoms right after a concussion puts a patient at higher risk for persistent symptoms. For example, a patient with only a headache and maybe blurred vision is probably going to have a better recovery compared with a patient who reports having headache, blurred vision, irritability, depression and balance problems.

Munro Cullum

Munro Cullum

Unknown genetic factors may contribute to protracted recovery from concussion. There may be biomarkers in the blood we can eventually detect, but right now we do not know why somebody is more susceptible to the effects of concussion than others. Having a history of concussion can put you at greater risk for protracted recovery, and if you have had a concussion, you are at greater risk for having another one.

The literature suggests some pre-existing symptoms such as a history of headaches, depression or other complicating factors like stress might contribute to prolonged symptoms. We do not understand that thoroughly yet. There is a lot we have to learn.

As far as treatment, if the patient has ongoing physical symptoms, such as balance or visual problems, medical consultation is indicated. If the symptoms are cognitive — for example, if they are still having memory problems — I would tell the patient to give it another couple of weeks. If the cognitive symptoms get worse with exertion, either physical or cognitive, I would recommend additional rest.

I would also assess to see if the patient has depression or anxiety at a clinically significant level because that might prolong recovery.

While the main concussion treatment is rest, physical and cognitive, we do not know how much is optimal. Sometimes, too much rest may be bad. For example, pulling all contact with the outside world for a teenage patient — completely taking away the cell phone, the iPad, television and contact with friends and/or school work for an extended period may actually cause more symptoms, but we do not know how much rest is ideal for whom yet.

Munro Cullum, PhD, ABPP, is a clinical neuropsychologist and professor of psychiatry and neurology & neurotherapeutics at UT Southwestern Medical Center in Dallas.
Disclosure: Cullum has no relevant financial disclosures.