Clemson facemask research continues in quest to help reduce brain injuries
CLEMSON – Football helmets have evolved since first introduced about 100 years ago. So when the Clemson Tigers and Alabama Crimson Tide battle it out in the College Football National Championship game Monday night, the teams’ helmets will be much safer than earlier versions.
But could football helmets be made even safer? A Clemson research team believes so.
The team, comprised of Gregory Batt, John DesJardins, Alex Bina, Davis Ferriel and Jay Elmore, is studying how future designs of facemasks can help improve the overall safety of football helmets. They are combining the fields of packaging science and bioengineering to study the impact performance of helmet systems.
“Previous research has determined the impact severity of helmets is both increased and decreased when facemasks are used, depending on the helmet used,” Bina said. “Our research involves establishing a testing system that differentiates between facemask performance and helmet performance.”
Stiffness of facemasks has been found to be a major contributor to the overall safety of football helmets. The research team has developed a system to test facemask stiffness and are working on computational models to assist in future facemask designs. By measuring the stiffness of a facemask during impact, the team is able to understand how the system will perform on the field and protect the player. This system can differentiate between individual facemask designs, materials and impact location. Perhaps most importantly, the research team has been able to measure decreases in impact performance of the facemask after prolonged use.
The number of vertical bars used in facemask design may play a part in the overall stiffness of a mask.
“These vertical bars have been shown to be optimal for reducing brain injury risk,” Bina said.
The number of bars on a facemask depends on a player’s position because they are designed to balance protection and visibility. Most facemasks are reinforced with an extra horizontal bar at the top of the face mask for better support and stability. Linemen usually wear closed-cage face masks that better protect the nose and eyes. Open-cage facemasks have more visibility than closed cage masks. These facemasks have a few horizontal and vertical bars below the nose and are most used among skill-position players, such as quarterbacks and receivers, who need more visibility on the field. Skill-position players also may have facemasks that sit farther away from their faces and leave their chins exposed, giving their heads more mobility.
Future research by the Clemson team will involve materials facemasks are made from. The team plans to evaluate the structural stiffness of titanium masks in addition to the steel masks already evaluated in this study.
The tests were conducted to comply with the National Operating Committee Standards for Athletic Equipment (NOCSAE) standards regarding the use of facemasks.
History of the research
This study began when Batt, an assistant professor in the Clemson food, nutrition and packaging sciences department; Bina, a doctoral student in bioengineering who also is a graduate research assistant in food, nutrition and packaging sciences; DesJardins, an associate professor of bioengineering and director of the Laboratory of Orthopaedic Design and Engineering; and Elmore, owner of Green Gridiron in Greenville, teamed up to determine how future designs of facemasks can help improve the overall safety of football helmets. Davis Ferriell, also a bioengineering graduate student, recently joined the team.
The team received a nearly $50,000 grant from the Robert H. Brooks Sports Science Institute for their study “Quantifying the Impact Performance of Football Helmet Facemasks.”
Bina said the goal of the study “…is to understand and evaluate the role a football helmet facemask plays in the overall impact performance of a football helmet system.
“We’re doing this by evaluating the mechanisms by which forces are transmitted from the facemask through the rest of the helmet system upon impact,” he said.
The team is working to help make helmets safer by creating a facemask that can help the helmet transfer g-forces away from the head. Traditional helmet design produces protective equipment that gradually decelerates the head upon impact. Facemasks prevent direct contact with players’ faces.
“Ideally, facemasks would deform slightly in order to produce gradual head deceleration, but not so much so as to put players at risk of injuring their faces,” Bina said. “However, the deformation properties of existing facemask designs are not available, making it impossible for doctors, trainers and parents to make informed decisions when purchasing a facemask for their helmet system. The first step in our facemask impact performance experimentation is to generate a ranking system of existing facemask designs based on their ability to deform.”
According to the National Institutes of Health, head injuries can occur when there is rapid change in the movement of the head, such as when a football player is tackled. Any significant force can have a detrimental effect on brain tissue. Batt said there are many different situations on a football field that cause rapid changes in velocity, or g-force.
“These situations can be player-to-player or player-to-turf interactions,” Batt said. “These rapid changes in velocity can cause the player’s brain to move around and smash against the player’s skull. This trauma can result in a brain injury.”
The facemask tests
The Clemson research team is using a linear drop tower system for its tests. Helmets tested in this manner are placed on an anthropomorphic head model and dropped from a specific height to generate a simulated football head impact. In the lab, the researchers said the linear drop tower testing system shows fewer than three impacts of 12 mph can cause permanent damage to facemasks. Football players of all positions commonly reach maximum velocities above 12 mph, especially on kickoff returns and coverage plays in both games and practice.
Using the linear drop system introduces many variables to the overall performance of a facemask design, including the helmet’s padding structure, the helmet’s outer shell and the chin strap buckles. Some facemask designs only fit one helmet style, but testing the entire helmet system will not specifically determine how one facemask performs compared to another.
“Because facemasks have been overlooked by the head impact research community, it is important to start at the structural and material level to determine appropriate facemask designs, then move into studying the method with which the facemask is attached to the helmet outer shell,” Bina said.
The facemask tests are being conducted in the Clemson Helmet Impact Performance Laboratory (CHIP LAB) of the Sonoco Institute of Packaging Design and Graphics laboratory on the Clemson campus. Some variables the researchers are studying include structural stiffness, resistance to permanent deformation and energy absorption. Over the course of a season, an NFL or college team may experience a handful of permanent facemask deformations in game situations, requiring the equipment staff to replace the facemasks on the sidelines. However, at the youth level, the course of a season’s worth of impacts in practices and games can permanently damage facemasks beyond repair.
“When we set out to investigate facemask performance in general, there was no literature out there,” DesJardins said. “From a research university’s perspective, this study is perfect. We’re researching something that is important but no one has done before.”
Statistics from the Centers for Disease Control indicate about 75 percent of traumatic brain injuries that occur each year are concussions. Sports is second only to car crashes as the leading cause of brain injury among people aged 15 to 24 years.
Football helmet images courtesy of Green Gridiron and the Smithsonian Institution.