Former NFL players score low—but normal—on motor tests

Former professional football players scored lower on motor tests than healthy controls, but the results were still within normal limits, according to new research that will be presented at the American Academy of Neurology’s Annual Meeting in April.

Repeated head injuries in football players and others have been linked to chronic traumatic encephalopathy (CTE), a degenerative brain disease that causes thinking, behavior, and mood problems. Problems with motor functions have also been documented among former boxers who sustained repeated head injuries and were later diagnosed with CTE. Researchers wanted to investigate whether former NFL players experience similar motor function problems from repeated head injuries.

“We found that while the motor functions of former NFL players were not as good as other men their age, they were still within normal range and not related to repeated head injury,” said study author Samuel Frank, MD, a neurologist at the Harvard Medical School.

The study involved 95 former NFL players between 40 and 69 years of age. Twenty-five men in the same age group who had no history of contact sports or head injury served as the control group. Participants were evaluated for speech, writing, eating, gait, posture, balance, and dexterity. Cognitive function tests and brain imaging were also performed. The study, referred to as DETECT, was conducted at Boston University School of Medicine.

Higher scores on the test indicate a greater impact of movement disorder symptoms. Results of the motor tests were low, but both NFL players and the control group were within the normal range. Former NFL players were found to have significantly higher scores than the control group (average score of 5 vs. 2 for controls). For reference, patients with Parkinson’s disease typically have scores from 10 to 60.

Participants with worse motor scores were also more likely to have worse scores on thinking skills and executive function tests. Overall, researchers found no relationship between an estimate of cumulative head impacts and motor scores.

“Our findings could signify that head trauma in football may have less impact on regions of the brain that control motor function than head trauma in boxing,” Dr. Frank said. “This research adds to what we already know about repeated head injuries and how they affect athletes. Larger studies are now needed to further test this hypothesis.”

The study was supported by the NIH. The participants’ travel was supported in part by JetBlue, the NFL, and the NFL Players Association.