Flag vs Tackle football: Safety & CTE INjuries
Choosing between tackle and flag football? This guide provides research-backed information on CTE risks, concussion rates, and the benefits of flag football for young athletes.
1. Tackle vs. Flag Football: An Overview of Safety and Play Styles
Comparing Safety Risks of Tackle Football and Flag Football
Tackle football, the traditional version of the sport, is characterized by its intense physicality and full-contact gameplay. Players wear helmets, shoulder pads, and other protective gear intended to mitigate the risks associated with tackles and high-impact collisions. However, despite these protective measures, tackle football remains one of the sports with the highest injury rates, particularly for concussions and other head traumas. The CDC and NFHS provide data confirming the high injury rates in tackle football.
Flag football offers a safer alternative that emphasizes strategy, agility, and teamwork. Instead of tackling opponents to the ground, players remove a flag attached to the opponent’s belt to end a play. This fundamental difference eliminates the high-impact collisions inherent in tackle football, significantly reducing the risk of serious injuries like concussions and subsequent long-term neurological consequences.
Unique Advantages of Flag Football
Beyond the reduced risk of injury, flag football offers some unique developmental advantages:
- Enhanced Hand-Eye Coordination and Precision: Pulling a flag requires a high degree of precision and hand-eye coordination. Players must accurately target a small, moving object while often running at full speed. This focus on precision develops fine motor skills and hand-eye coordination to a greater extent than tackling, which relies more on brute force and body mass.
- Greater Freedom for Skill Development: By eliminating the risk of life-altering tackle injuries, flag football gives players the freedom to experiment with more skill-demanding moves and dekes while running with the ball. Players can confidently try different spins, jukes, and cuts without fear of being tackled hard, leading to more risk-free opportunities for skill development and creativity on the field. This can lead to more dynamic and exciting gameplay, while also fostering greater confidence in young athletes.
While both versions of football offer physical and social benefits, flag football is increasingly recognized as a safer and developmentally beneficial option, especially for young athletes whose brains and bodies are still developing. It allows players to learn the fundamentals of the sport, such as passing, catching, and route running, without exposing them to the elevated risks of head trauma prevalent in tackle football.
This early exposure to the sport's fundamentals can even translate to improved skill development if they transition to tackle football later on. However, while skill development and enjoyment are important aspects of youth sports, the primary concern for many parents is the long-term health and safety of their children. This leads us to a crucial discussion about the potential long-term consequences of head injuries, specifically a condition known as Chronic Traumatic Encephalopathy, or CTE.
References:
- Flag Football Is a Safer, More Inclusive Pipeline for the NFL. Can It Be More? - https://live-global-sport-matter.ws.asu.edu/business/2023/05/10/flag-football-safer-inclusive-pipeline-nfl-can-it-be-more/#:~:text=They%20both%20can%20exist.,easily%20be%20translated%20into%20tackle.”
- Benefits of Youth Sports: Malina, R. M. (2010). Early sport specialization: Roots, effectiveness, risks. Current sports medicine reports, 9(6), 364–371. https://pubmed.ncbi.nlm.nih.gov/21068571/
2. A DeepEr Dive into CTE Injuries
What Exactly Is a CTE Injury?
Chronic Traumatic Encephalopathy (CTE) is a progressive neurodegenerative disease associated with repetitive head impacts (RHIs), including both concussions and subconcussive impacts (i.e., blows to the head that do not cause immediate symptoms).
These impacts can lead to the accumulation of hyperphosphorylated tau protein in the brain, forming neurofibrillary tangles, which disrupts normal neuronal function and causes widespread neurodegeneration. In other words, we see a dysregulation in our brain cells that prevents our brain from functioning properly.
Unlike acute traumatic brain injuries (TBIs), CTE develops gradually over time and may remain asymptomatic for years, even decades. While direct head impacts are the most clearly established risk factor, research suggests that repetitive bodily impacts that cause significant head movement may also contribute to the development of CTE.
The disease is most commonly observed in individuals with a history of contact sports, military personnel exposed to blast injuries, and victims of physical abuse. Research published in Brain by McKee et al. (2013) provided definitive pathological criteria for CTE, establishing its distinct characteristics. Even subconcussive impacts, once thought to be benign, are now recognized as contributing to the development of CTE (Stern et al., 2011).
What Are the Symptoms of CTE?
Symptoms of CTE are diverse and can vary depending on the severity and duration of head trauma, as well as individual factors. Early symptoms may be subtle and easily overlooked, but they can progressively worsen over time. Common symptoms include:
- Headaches
- Memory loss and cognitive impairment
- Difficulty concentrating and executive dysfunction
- Depression, anxiety, and irritability
- Mood swings, impulsivity, and behavioral changes
- Impaired judgment and decision-making
- Cognitive decline and dementia in advanced stages
- Sleep disturbances and insomnia
- Suicidal thoughts or behavior
Genetic factors may also play a role in an individual's susceptibility to CTE, influencing the inflammatory response and tau protein accumulation.
The Development of CTE: Complex and Insidious
CTE's progression is challenging to diagnose and treat due to its delayed onset and overlapping symptoms with other neurological conditions like Alzheimer's disease. Current diagnostic methods rely on post-mortem neuropathological examination of brain tissue. However, advancements in neuroimaging techniques, such as tau PET scans, and blood-based biomarkers are showing promise for earlier in-vivo detection (Stern et al., 2019).
The cumulative effect of repetitive head trauma, even from impacts that do not result in diagnosed concussions, is a primary risk factor in CTE development. The insidious nature of the disease often leads to delayed diagnosis, with symptoms often being dismissed or misattributed until significant impairments manifest.
The Long-Term Effects of CTE
The consequences of CTE are profound and devastating, significantly impacting cognitive, emotional, and physical well-being. These effects can manifest in various ways and can severely diminish an individual's quality of life. Long term effects include:
- Cognitive Decline and Dementia: This is a hallmark of CTE, impacting memory, attention, executive function (planning, decision-making), and language skills. In severe cases, it can progress to full-blown dementia, making independent living nearly impossible.
- Mood and Behavioral Disturbances: CTE can lead to significant mood swings, irritability, impulsivity, aggression, depression, and anxiety. These changes can strain relationships, lead to social isolation, and significantly impact daily life.
- Motor Impairments: In some cases, CTE can lead to motor impairments, including problems with balance, coordination, speech, and movement. These can further limit an individual's independence and ability to perform everyday tasks.
- Increased Risk of Suicide: The combination of cognitive decline, mood disturbances, and behavioral changes can significantly increase the risk of suicidal thoughts and behavior in individuals with CTE. This is a particularly tragic and devastating consequence of the disease.
- Impact on Family and Caregivers: The effects of CTE extend beyond the individual directly affected. Family members and caregivers often bear a significant burden, dealing with the challenges of caring for someone experiencing cognitive decline, behavioral changes, and emotional instability.
The long-term effects of CTE are clearly devastating, impacting individuals and their families in profound ways. However, it is especially critical to consider these potential consequences in the context of young, developing brains.
Children and adolescents are particularly vulnerable to the damaging effects of repetitive head impacts due to the ongoing development and plasticity of their brains. This heightened vulnerability means that the consequences of head injuries sustained during youth can be even more severe and long-lasting.
References:
- Chronic Traumatic Encephalopathy: Is Latency in Symptom Onset Explained by Tau Propagation? - https://pmc.ncbi.nlm.nih.gov/articles/PMC5793739/#:~:text=There%20are%20often%20many%20years,of%20clinical%20symptoms%20of%20CTE.
- Effects of Subconcussive Head Trauma on the Default Mode Network of the Brain - https://pmc.ncbi.nlm.nih.gov/articles/PMC4238241/#:~:text=Further%2C%20research%20shows%20that%20the,impairment15%20and%20disorders%20like
- Chronic traumatic encephalopathy (CTE): criteria for neuropathological diagnosis and relationship to repetitive head impacts - https://pmc.ncbi.nlm.nih.gov/articles/PMC10020327/
- Comparing Head Impacts in Youth Tackle and Flag Football - https://www.cdc.gov/traumatic-brain-injury/data-research/comparing-head-impacts/index.html#:~:text=Youth%20tackle%20football%20athletes%20had%20an%20estimated%2018%20times%20more,game%20than%20flag%20football%20athletes.
- Why Some People’s CTE Symptoms Are More Severe Than Others - https://www.bu.edu/articles/2018/severity-of-cte-symptoms-genetics-influenced/#:~:text=But%20among%20people%20diagnosed%20with,likely%20to%20have%20higher%20accumulation
- Chronic traumatic encephalopathy (CTE) dementia - https://www.dementia.org.au/about-dementia/chronic-traumatic-encephalopathy-cte-dementia
- Long-term consequences of repetitive brain trauma: chronic traumatic encephalopathy - https://pubmed.ncbi.nlm.nih.gov/22035690/#:~:text=CTE%20results%20in%20a%20progressive,%2C%20aggressiveness%2C%20parkinsonism%2C%20and%2C
- Trends in Concussion Incidence in High School Sports: A Prospective 11-Year Study - https://journals.sagepub.com/doi/10.1177/0363546510392326
3. The Impact of Head Injuries on Developing Kids vs. Adults
Unique Vulnerabilities of Developing Brains
The human brain undergoes rapid growth and complex structural and functional changes during childhood and adolescence. Processes such as myelination, synaptogenesis, and synaptic pruning are crucial for cognitive and emotional development.
- Myelination: Think of myelin as the insulation around electrical wires. It coats nerve fibers (axons) in the brain, allowing signals to travel faster and more efficiently. During childhood and adolescence, this insulation is still being built, making the connections between brain cells more vulnerable to disruption. Imagine trying to send a message through a frayed wire – the signal gets weaker and slower.
- Synaptogenesis: This is the process of forming connections (synapses) between brain cells. During childhood, the brain is creating a vast network of these connections, like building a complex web. This makes the brain highly adaptable but also more susceptible to damage if these connections are disrupted by injury. It's like building a delicate web that can easily be torn.
- Synaptic Pruning: While the brain is busy creating connections, it's also pruning away unused ones, like trimming a tree to encourage stronger growth. This process refines the brain's circuitry, making it more efficient. However, if this pruning process is disrupted by injury, it can lead to problems with learning and development. It's like pruning the tree incorrectly, which can stunt its growth.
These ongoing developmental processes make the young brain particularly vulnerable to the damaging effects of head trauma. Repetitive head impacts during this critical period can disrupt these finely tuned developmental processes, leading to long-term deficits in cognitive functions such as memory, attention, executive function, and emotional regulation.
Why Kids Are at Greater Risk
Children and adolescents are more susceptible to head injuries than adults due to several factors:
- Thinner skulls and weaker neck muscles, providing less protection against head acceleration and deceleration forces.
- Larger head-to-body size ratios, increasing the momentum of head movement during impacts.
- Ongoing brain development, making neural connections more vulnerable to disruption. The younger the child, generally speaking, the more vulnerable the brain is.
- Longer recovery times from concussions compared to adults. Younger kids can take up to three times longer to recover from concussion than adults in some cases!
These factors make the risk-reward profile of tackle football particularly concerning for young athletes. Flag football, by minimizing head impacts, offers a safer alternative while still providing the physical, social, and developmental benefits of team sports.
However, to fully understand the scope of the risk and to develop effective prevention strategies, it's crucial to examine the growing body of research dedicated to understanding CTE.
References:
- Are children more susceptible to concussions than adults? - https://yeghip.com/faq/are-children-more-susceptible-to-concussions-than-adults/
- Functional myelin in cognition and neurodevelopmental disorders - https://pmc.ncbi.nlm.nih.gov/articles/PMC11016012/#:~:text=Myelination%20is%20therefore%20a%20long,and%20adaptability%20of%20cognitive%20processes.
- The Neurobiology of Childhood Structural Brain Development: Conception Through Adulthood - https://pmc.ncbi.nlm.nih.gov/articles/PMC4114219/#:~:text=Similar%20to%20the%20cortex%2C%20subcortical,and%20adolescence%20
- Agency for Clinical Innovation - Understanding brain injury specialist rehabilitation in NSW - https://aci.health.nsw.gov.au/publications/brain-injury-rehab/part-a-specialist/developmental-considerations/stages#:~:text='However%2C%20more%20recent%20research%20suggests,injury%20than%20people%20who%20are
- Common Myths About Kids and Concussions - https://www.hackensackmeridianhealth.org/en/healthu/2019/03/28/common-myths-about-kids-and-concussions
4. Advances In CTE Research
The Pivotal Role of the Boston University CTE Center
Scientists have made significant progress in understanding a brain condition called Chronic Traumatic Encephalopathy, or CTE, which is linked to repeated hits to the head. A leading group in this research is the Boston University CTE Center. They've been instrumental in helping us understand what CTE is, how it develops, and what it means for long-term health. Here’s what they’ve discovered:
1. Defining CTE:
Before the work of the Boston University researchers, it was difficult to definitively say whether someone had CTE. They developed the first clear way to identify CTE by looking at changes in the brain after death. This was a huge step forward, allowing scientists worldwide to study CTE consistently. They found that CTE has a unique pattern of damage, especially around blood vessels in the brain.
2. A Closer Look at the Brain:
The researchers at Boston University don't just look for one thing; they examine many aspects of the brain to get a complete picture of the damage caused by CTE. This includes:
- Tau Protein Analysis: They carefully study a protein called "tau," which builds up abnormally in the brains of people with CTE. This buildup disrupts how brain cells work.
- Changes in brain matter: They also look at changes in the brain tissue itself, including both "grey matter" (where brain cells are located) and "white matter" (which connects different parts of the brain). They look for things like cell loss and damage to the connections between brain cells.
- Neuro-Inflammation: They also study inflammation in the brain, which is the body's natural response to injury. In CTE, this inflammation can become chronic and contribute to ongoing damage.
- Other Damage: They also look for other types of damage and changes that can occur in the brain such as blood vessel damage, cerebral amyloid angiopathy, and the presence of other proteins related to TAU protein and CTE, such as protein TDP-43.
3. How CTE Develops
By studying these brain changes, the Boston University researchers are figuring out how repeated hits to the head can lead to CTE. They’re investigating how these hits trigger the problems with tau protein and other damage, and how this damage spreads over time.
4. Tracking the Progression of CTE
The researchers have also developed a way to track how CTE progresses in the brain, from early to more advanced stages. This helps them understand how the damage relates to the symptoms people experience.
5. Raising Awareness:
Beyond their research, the Boston University CTE Center has played a key role in raising public awareness about the risks of head impacts in sports and other activities. Their work has helped to promote safer practices and policies.
The detailed research conducted by the Boston University CTE Center provides critical context for understanding the potential risks associated with head impacts. Their work has been instrumental in showing how repeated hits to the head can damage the brain.
But what does this damage translate to in real-world scenarios? What are the actual numbers telling us about the prevalence of CTE, particularly in football players at different levels? Let's now turn our attention to some key statistics that paint a clearer picture of the risks.
References:
- National Institute of Neurological Disorders and Stroke Consensus Diagnostic Criteria for Traumatic Encephalopathy Syndrome - https://pmc.ncbi.nlm.nih.gov/articles/PMC8166432/
- Current Understanding of Chronic Traumatic Encephalopathy - https://pmc.ncbi.nlm.nih.gov/articles/PMC4255271/#:~:text=In%202013%2C%20McKee%20and%20colleagues,CTE%2C%20presenting%20proposed%20criteria%20for
- Neuroanatomy, Gray Matter - https://www.ncbi.nlm.nih.gov/books/NBK553239/
- Microglial neuroinflammation contributes to tau accumulation in chronic traumatic encephalopathy - https://pmc.ncbi.nlm.nih.gov/articles/PMC5084333/#:~:text=Activated%20microglia%20and%20persistent%20neuroinflammation,ptau%20pathology%20and%20lead%20to
- Chronic Traumatic Encephalopathy is associated with TDP-43 Retinal Pathology - https://iovs.arvojournals.org/article.aspx?articleid=2768896#:~:text=Brain%20pathology%20in%20CTE%20is,later%20stages%20of%20the%20disease.
5. Injury Statistics in Tackle Football vs. Flag Football
CTE Risks in Tackle Football
The research from the Boston University CTE Center, combined with other studies, reveals some alarming statistics about the link between football and CTE. These numbers highlight the potential consequences of repetitive head impacts, both in professional athletes and, perhaps most concerning, in young players whose brains are still developing and therefore more vulnerable to long-term damage.
1. A study in JAMA by Mez et al. (2017) found CTE in 99% of deceased NFL players' brains examined.
This highly publicized study examined the brains of 111 deceased former NFL players. Of those, 110 (99%) showed neuropathological evidence of CTE. This striking finding significantly raised public awareness of the link between professional football and CTE. It demonstrates the potential severity of the condition in those exposed to years of repetitive head trauma at the highest levels of the sport.
2. A 2017 JAMA study also reported CTE in 87% of former high school football players who donated their brains for research.
This companion study, also published in JAMA by Mez et al. (2017), examined the brains of 53 deceased former high school football players. Of those, 48 (87%) showed pathological evidence of CTE. This finding is particularly alarming given the vulnerability of developing brains, suggesting that even exposure during adolescence can have severe and lasting consequences.
3. Consistent findings show a high prevalence of CTE in former football players at all levels, including college and professional, reinforcing the concern that repetitive head trauma, especially during youth, presents a significant risk for developing CTE.
Multiple studies have consistently demonstrated a high prevalence of CTE in former football players at all levels of play. This reinforces the concern that repetitive head trauma, especially during youth when the brain is still developing, presents a significant risk for developing CTE. The fact that CTE has been found in former high school players underscores the urgency of addressing head trauma in youth sports.
Safety in Flag Football vs Other Sports
n contrast, flag football presents a significantly lower risk of CTE and other head injuries due to the elimination of tackling and high-impact collisions. While large-scale, long-term studies specifically on CTE in flag football are limited (due to the relatively recent rise in its popularity and the long latency of CTE), the fundamental difference in gameplay strongly suggests a reduced risk. Studies focusing on concussion rates in flag football show significantly lower incidence compared to tackle football.
And yet, CTE risks are not exclusive to football. Other sports with a risk of head injuries include:
- Ice Hockey: High-speed collisions, body checking, and fighting are major contributors to head trauma. While research is ongoing, studies like one by Omalu et al. (2010) that found CTE in a deceased former professional hockey player suggest a potential risk in this sport as well.
- Boxing and Mixed Martial Arts (MMA): Repeated blows to the head place fighters at a very high risk of developing CTE. Given the nature of these sports, where head trauma is a primary concern, the risk is considered substantial.
- Rugby: Similar to tackle football, rugby involves frequent high-impact collisions and tackling. Studies have found evidence of CTE in deceased rugby players, indicating a potential risk similar to tackle football.
- Soccer: Heading the ball and collisions with other players can contribute to increased CTE risks. A study by McKee et al. (2016) found CTE in 4 out of 5 deceased soccer players whose brains were examined, highlighting that even the different nature of head impacts in soccer can pose a risk.
While the research on CTE in these other sports is not as extensive as in American football, these findings underscore that repetitive head impacts across various sports and activities can have serious long-term consequences. So, given these concerning findings, what can we do to protect our young athletes? Let's take a look at some key steps we can take to move forward and prioritize safety.
References:
- New Study of 111 Deceased Former NFL Players Finds 99 Percent Had CTE - https://www.bumc.bu.edu/camed/2017/07/25/new-study-of-111-deceased-former-nfl-players-finds-99-percent-had-cte/#:~:text=The%20findings%20of%20the%20largest,suggest%20that%20CTE%20may%20be
- Study Details CTE in Football Players - https://www.mdedge.com/neurology/article/145375/alzheimers-cognition/study-details-cte-football-players
- Researchers Find CTE in 345 of 376 Former NFL Players Studied - https://www.bumc.bu.edu/camed/2023/02/06/researchers-find-cte-in-345-of-376-former-nfl-players-studied/#:~:text=The%20Boston%20University%20CTE%20Center,encephalopathy%20(CTE)%20out%20of%20376
- New Study Reveals Number and Strength of Head Impacts, Not Concussions, Drive CTE Risk in Football Jun 20, 2023 - https://www.massgeneralbrigham.org/en/about/newsroom/press-releases/head-impacts-not-concussions-drive-cte-risk-in-football
- Soccer (Football Association) and chronic traumatic encephalopathy: A short review and recommendation - https://pmc.ncbi.nlm.nih.gov/articles/PMC5674664/
- Fighting and Penalty Minutes Associated With Long-term Mortality Among National Hockey League Players, 1967 to 2022 - https://pmc.ncbi.nlm.nih.gov/articles/PMC10173025/#:~:text=Fighting%20exposes%20players%20to%20repetitive,increased%20risk%20of%20developing%20CTE.
- Duration of Ice Hockey Play and Chronic Traumatic Encephalopathy - https://pmc.ncbi.nlm.nih.gov/articles/PMC11618473/
- A Systematic Review and Meta-Analysis Investigating Head Trauma in Boxing - https://pmc.ncbi.nlm.nih.gov/articles/PMC10597432/#:~:text=Chronic%20traumatic%20brain%20injury%20or,be%20the%20most%20severe%20health
- Head-Impact Mechanisms in Men's and Women's Collegiate Ice Hockey - https://meridian.allenpress.com/jat/article/49/4/514/191262/Head-Impact-Mechanisms-in-Men-s-and-Women-s
6. NEXT STEPS: Prioritizing Safety and Making Informed Choices
CTE Risks in Tackle Football
Sports offer numerous benefits, including improved physical health, teamwork skills, discipline, and social development. However, the evidence is clear: repetitive head impacts, especially during youth, pose a significant risk to long-term brain health, and so the risks associated with tackle football, particularly the long-term consequences of CTE, necessitate a careful and informed approach.
For younger athletes, flag football provides a safer entry point to the sport, allowing them to enjoy its benefits while minimizing the risk of head trauma during critical periods of brain development.
While completely eliminating all risk in sports is impossible, there are steps we can take to minimize the danger and make informed choices.
fOR pARENTS aND yOUNG aTHLETES
- Consider Flag Football: For younger children, flag football offers a safer introduction to the sport, allowing them to develop fundamental skills without the high-impact collisions of tackling.
- Open Communication: Encourage open communication between athletes, parents, coaches, and medical professionals about any head injuries or concussion symptoms.
- Concussion Awareness: Educate yourself and your children about the signs and symptoms of concussion and the importance of proper recovery. The CDC's HEADS UP program is a great resource
- Prioritize Long-Term Health: Emphasize the importance of long-term health and keep it in balance with short-term athletic achievements. Nothing should be more important than the health and well-being of the athlete.
fOR cOACHES AND oRGANIZATIONS
sTRICT cONCUSSION pROTOCOLS
- Immediate Removal from Play: Any athlete who exhibits any signs or symptoms of a concussion (e.g., loss of consciousness, confusion, dizziness, headache, memory problems, balance issues) must be immediately removed from play or practice. This applies regardless of the severity of the impact or the athlete's desire to continue playing.
- "When in Doubt, Sit Them Out": This is a crucial principle. If there is any suspicion of a concussion, the athlete should be removed from play. It's always better to err on the side of caution.
- Evaluation by a Qualified Healthcare Professional: The athlete must be evaluated by a healthcare professional trained in concussion management (e.g., physician, athletic trainer, neuropsychologist) before being allowed to return to play. This evaluation should include a thorough assessment of cognitive function, balance, and other relevant factors.
- Graduated Return-to-Play Protocol: A gradual, step-wise return-to-play protocol should be followed under the supervision of a healthcare professional. This protocol typically involves increasing levels of physical activity over several days, with each step requiring the athlete to be symptom-free. If symptoms return at any point, the athlete should return to the previous step.
oTHER bEST pRACTICES
Parent and Athlete Education: Coaches and organizations should provide comprehensive education to parents and athletes about concussion symptoms, risks, and management. This should be done at the beginning of each season.
Documentation: All suspected and diagnosed concussions should be documented, including the date of injury, symptoms, evaluation findings, and return-to-play progress.
Limit Contact in Practice: Reduce the amount of full-contact drills in practice to minimize repetitive head impacts.
Ongoing Education: Provide ongoing education for coaches, players, and parents on concussion prevention, recognition, and management.
7. In Summary
MakE An Informed decision
The choice between flag and tackle football is a deeply personal one for families. However, the growing body of scientific evidence regarding the long-term consequences of repetitive head impacts, particularly on developing brains, makes a compelling case for prioritizing safety. Research, especially from the Boston University CTE Center, has shown a clear link between repetitive head impacts and CTE, a devastating neurodegenerative disease.
While tackle football carries a significant risk of these impacts, flag football offers a safer alternative, allowing young athletes to experience the camaraderie, physical activity, and skill development of football without the same level of risk.
By choosing flag football, parents can provide their children with the opportunity to enjoy the benefits of the sport while significantly reducing their risk of long-term brain damage. Ultimately, the goal is to ensure that children can participate in sports safely and enjoy a healthy future, both on and off the field.
