AAOS Now

Published 1/1/2014

Concussion in the News

Recently, AAOS Headline News Now has reported on several stories in the media dealing with concussions. Following are summaries of these stories:

Hiding symptoms
“Don’t Tell Coach: Playing Through Concussions” by Jan Hoffman for The New York Times looks at what the Institute of Medicine (IOM) identified as a “culture of resistance” among high school and college athletes, who may eschew examination by coaches and trainers in order to more quickly return to playing. According to the IOM report, “The culture of sports negatively influences athletes’ self-reporting of concussion symptoms and their adherence to return-to-play guidance.”

The article cites study data presented at the annual meeting of the Pediatric Academic Societies. A survey of 119 high school football players found that more than 75 percent could identify the symptoms of a concussion and 92 percent of the players knew they risked serious injury if they returned to the field too quickly after concussion. Yet just 54 percent said that they would report such symptoms to the coach, and 53 percent said that they would continue to play even if they had a headache from such an injury.

Helmet impact sensors
A video on the
CNN.com website looks at the issue of impact sensors in football helmets. Manufacturers state that such devices do not see or diagnose concussions, and few of the products have been subjected to peer-reviewed studies. A physician who serves as the director of the Michigan NeuroSport Program suggests that impact sensing technologies could be useful if used cautiously, but dangerous if relied upon too much.

A group of researchers who conducted a test for CNN dropped a helmet from a variety of heights and found that a drop from 5 feet—well into the range for potential concussion—did not trigger any of the three sensors attached to the helmet. However, one football coach suggests that use of such sensors may increase safety through a secondary effect: When his players did a trial run wearing helmets with sensors, they appeared to be more aware of head trauma and behaved in a manner to prevent setting them off.

Recovery after concussion
According to “A Prospective Study of Gray Matter Abnormalities in Mild Traumatic Brain Injury,” a study in the journal Neurology, recovery for concussion may have two different modes, with the memory, thinking, and behavioral symptoms improving more quickly than the physiologic injuries in the brain. The matched cohort study involved 50 patients with mild traumatic brain injury (mTBI) and 50 controls.

All 50 patients were evaluated approximately 2 weeks after injury, and 26 patients returned for 4-month follow-up. During the semiacute injury phase, patients with mTBI reported more cognitive, somatic, and emotional complaints, which were significantly reduced 4 months postinjury. In addition, patients displayed evidence of increased fractional anisotropy on both sides of the superior frontal cortex during the semiacute phase, and levels remained elevated in the left side at 4-month follow-up. No significant differences were found between patients with mTBI and matched controls on neuropsychological testing, measures of gray matter atrophy, or mean diffusivity at either time point.

Study: Blood test might help identify concussion
Data published online in the journal Frontiers in Neurology suggest that a blood test could help identify concussion. The authors drew data on 38 participants enrolled in a larger study of mTBI. Overall, 17 participants had sustained a head injury caused by blunt trauma, acceleration, or deceleration forces; 13 had an orthopaedic injury; and 8 were healthy, uninjured, demographically matched controls. They found that plasma levels of the neurodegeneration biomarker calpain-cleaved alpha-Type II spectrin N-terminal fragment (SNTF) were at least twice the lower limit of detection in 7 of 17 mTBI cases, 3 of 13 orthopaedic cases, and none of the uninjured controls.

Elevation in plasma SNTF was associated with significant differences in fractional anisotropy and the apparent diffusion coefficient in the corpus callosum and uncinate fasciculus measured by diffusion tensor imaging. In addition, increased plasma SNTF on the day of injury correlated significantly with cognitive impairment persisting for at least 3 months, both across all study participants and also among the mTBI cases separately.

The authors note that an elevation in plasma SNTF in the subset of orthopaedic injury cases, accompanied by corresponding white matter and cognitive abnormalities, raises the possibility of identifying undiagnosed cases of mTBI.