Concussion in Football — Recognition, Management, and Long-Term Concerns

Introduction

Football’s relationship with head injury has undergone significant reappraisal in the past decade. Where heading the ball was once considered a fundamental, unconcerning skill, emerging research on cumulative sub-concussive head impact exposure and chronic traumatic encephalopathy (CTE) in former players has raised serious questions about long-term neurological health. Simultaneously, the recognition and management of acute concussion remains inconsistent at all levels of football. Understanding current concussion science is not optional for football medical staff — it is an ethical and clinical imperative.

The Science

Concussion definition: A traumatic brain injury (TBI) characterised by a complex pathophysiological process affecting the brain, induced by biomechanical forces — potentially involving loss of consciousness (not required for diagnosis) and a constellation of clinical signs and symptoms reflecting functional disturbance rather than structural injury.

Mechanism: Rotational and shear forces from head impact (ball, elbow, ground, player collision) cause stretching and distortion of neural axons. The resulting ionic flux (K⁺ efflux, Na⁺ influx, Ca²⁺ influx) creates a neuronal energy crisis — increased ATP demand during decreased cerebral blood flow. This neurometabolic mismatch is the pathophysiological basis for concussion vulnerability: a second impact during this window is disproportionately dangerous (second impact syndrome).

SCAT6 — the assessment tool: The Sport Concussion Assessment Tool 6th Edition (Amsterdam consensus, 2022; successor to SCAT5) is the recommended sideline assessment. Components:

• Symptom evaluation: 22 symptoms rated 0–6 severity
• Cognitive assessment (orientation, immediate recall, concentration, delayed recall)
• Balance assessment (BESS — Balance Error Scoring System)
• Neurological screening

Sensitivity: moderately high when applied within 3 hours of injury; decreases with time. Not diagnostic — a clinical decision tool.

Sub-concussive head impacts: Heading involves impacts below the clinically symptomatic concussion threshold but still involving rotational brain acceleration. Research using functional MRI and diffusion tensor imaging shows measurable microstructural white matter changes after heading exposure — changes that accumulate across a career. The clinical significance of these changes is under investigation.

Chronic Traumatic Encephalopathy (CTE): A progressive neurodegenerative disease associated with repetitive head trauma, characterised by tau protein accumulation in specific brain regions. CTE can only be definitively diagnosed post-mortem. Former NFL players, boxers, and increasingly former professional footballers have been found to have CTE at autopsy. The 2019 FIELD study (University of Glasgow, New England Journal of Medicine) found that former professional Scottish footballers had a 3.5× higher risk of neurodegenerative disease than age-matched controls.

Heading restrictions in youth football: In response to emerging evidence, US Soccer Federation and several football associations have restricted or eliminated heading in youth football below age 10–11. England banned heading in youth training (under-12) in 2020.

What Research Says

Fehily and Fitzgerald (2017) reviewed the potential mechanisms of damage after repeated mild traumatic brain injury — including excitotoxicity, disturbed blood flow and metabolism, oxidative stress, blood-brain barrier dysfunction, inflammation and diffuse axonal injury — drawing largely on rodent models, and concluded that the chronic consequences of repeated mild impacts are not yet fully understood.

Uomoto et al. (2019) reviewed heading-induced neurophysiological changes in Frontiers in Neurology, finding measurable cognitive and neuroimaging changes following single heading sessions that resolved within 24–48 hours — but noting that cumulative exposure across a career may not fully resolve.

Mackay et al. (2019) published the FIELD study in NEJM, demonstrating that former Scottish professional footballers had 3.5× higher mortality from neurodegenerative disease (Alzheimer’s, Parkinson’s, motor neurone disease) than age-matched general population controls — representing the most significant epidemiological evidence linking professional football to long-term neurological harm.

Did You Know? The “heading debate” in football is partly a confound problem: heading and head collisions are different things. Pure ball-to-head contact in a well-executed header generates approximately 14–55 g of head acceleration — below injury thresholds. The head-to-head, head-to-elbow, and head-to-ground collisions that often accompany aerial duels generate much higher forces. Separating the risk of heading technique from the collision risk in the aerial contest context is important for policy decisions — the evidence may suggest restricting aerial collision drills (elbow use, body contact) rather than heading technique training.

Applied to Football

Concussion management protocol:

1. If in doubt, sit them out. No player with suspected concussion should return to play on the same day. This is a clinical principle, not a tactical preference.
2. SCAT6-trained assessors on every match sideline. All team medical staff should be SCAT6-trained. Formal sideline assessment takes 10 minutes — appropriate for a halftime or injury break assessment.
3. Graduated Return to Sport (GRTS) protocol. 6-stage protocol from complete rest through full training — minimum one day per stage, no stage advancement if symptoms return. Minimum 7 days from symptom resolution to match return.
4. Heading restrictions in youth training. Consider adopting heading restrictions below age 12 in training environments — match heading is different risk context from repetitive training heading drill exposure.
5. Long-term neurological welfare monitoring for former players. Professional clubs have an ethical responsibility to provide neurological health monitoring for long-serving former players — the FIELD study data creates a moral obligation that cannot be ignored.

Key Takeaways

• Concussion is a functional neurometabolic disturbance — structural imaging is usually normal but functional deficits are real
• SCAT6 is the recommended standardised sideline assessment tool
• The FIELD study demonstrated 3.5× higher neurodegenerative disease mortality in former professional footballers
• Graduated Return to Sport requires minimum 7 days from symptom resolution — same-day return is never appropriate
• Sub-concussive heading exposure shows measurable neuroimaging changes — long-term significance under active investigation

References

• Mackay, D. F., Russell, E. R., Stewart, K., MacLean, J. A., Pell, J. P., & Stewart, W. (2019). Neurodegenerative disease mortality among former professional soccer players. New England Journal of Medicine, 381(19), 1801–1808.
• Fehily, B., & Fitzgerald, M. (2017). Repeated mild traumatic brain injury: potential mechanisms of damage. Cell Transplantation, 26(7), 1131–1155.
• McCrory, P., Meeuwisse, W., Dvorak, J., Aubry, M., Bailes, J., Broglio, S., & Vos, P. E. (2017). Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016. British Journal of Sports Medicine, 51(11), 838–847.

Written by Hüseyin Akbulut, MSc Sport Scientist · Founder of Sporeus

Hüseyin Akbulut is the founder of Sporeus and author of THRESHOLD (EŞİK), a 540-page Turkish-language book on endurance science.

• 540pp THRESHOLD Book
• MSc Sport Sciences
• Marmara University

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