For the second time in three years, data collected by a joint NFL/NFL Players Association committee shows no significant difference in the rate of non-contact lower-extremity injuries incurred by players on synthetic turf versus natural grass.
Jeff Miller, the NFL's executive vice president for communications, public affairs and policy, told ESPN that the similar rates point to a "need to look at all surfaces" for ways to improve player safety. NFLPA executive director Lloyd Howell last fall called on all teams to convert to grass fields after Aaron Rodgers tore his left Achilles tendon on MetLife Stadium's synthetic turf during his first series as the New York Jets quarterback.
MetLife is one of 15 NFL stadiums, out of 30 total, that employ some type of synthetic playing surface.
In a statement released to ESPN this week, the union said the numbers were close in 2023 only because injuries on grass fields increased.
"As we have said repeatedly, injury data in a one-year time capsule does not account for what we have known since we started tracking these injuries: that a well-maintained, consistent grass surface is still simply safer for players than any synthetic field," the statement read. "The story of last year's injury data is that, unfortunately, injury rates on grass have increased from last year.
"The data cannot, however, account for what players have shared with the NFL for years: that we feel much worse after playing on synthetic surfaces and overwhelmingly prefer consistent, high-quality grass fields.
"This year's injury data also does not explain how quick they are to flip NFL stadium surfaces from bad synthetic to better grass for international soccer friendlies and tournaments."
The NFL/NFLPA committee defines injuries that could be attributed to the playing surface as those that occur in the lower extremities, without contact from another player, and are serious enough to force missed games, according to ESPN. They represent about one-third of all NFL injuries and about half of all lower-extremity injuries, according to Dr. Mackenzie Herzog, an epidemiologist at IQVIA and an adviser to the NFL and NFLPA.
In 2023, the incidence rate (per 100 plays) for such injuries was 0.001 higher on synthetic turf (0.043) compared with natural (0.042), ESPN's Kevin Seifert and Dan Graziano reported. That represented a total of six to eight injuries over the course of the 17-week season, Herzog said, making the rates "virtually identical." There was a similar difference between the rates in 2021.
In 2022, the rate for synthetic turf was 0.048 and the rate for natural was 0.035.
"Sometimes the line for synthetic injuries goes up, and sometimes it goes down," the NFL's Miller said, "and the same for the natural turf line. We need to have a better appreciation for why that could be over time so that both lines are heading in the same direction, and both of them are going down."
A total of 11 NFL players, including Rodgers, suffered Achilles tears during regular-season games. There were another 12 during preseason games and practices, and the overall total of 23 was in line with previous seasons. According to NFL chief medical officer Dr. Allen Sills, the NFL's number of Achilles injuries has been between 20 and 22 since the league moved to a 17-game regular season.
"We did not see an epidemic of Achilles injuries this year," Sills said.
According to ESPN, several teams replaced a type of synthetic turf called "slit film" after the 2022 season, noting that it had produced higher injury rates than other forms of turf and grass. Two others will do so after the 2023 season, leaving Cincinnati's Paycor Stadium as the only facility without plans to replace slit-film turf before the 2024 season.
In the meantime, the committee is researching the impact of establishing a consistent set of turf management and style protocols to reduce the adjustments players must make from stadium to stadium, Seifert and Graziano reported.
