reviewed injury data from NFL games played between 2000 and 2009. They wrote, "...the injury rate of knee sprains as a whole was 22% higher on FieldTurf than on natural grass. While MCL sprains did not occur at a rate significantly higher than on grass, rates of ACL sprains were 67% higher on FieldTurf." Studies of the safety of FieldTurf are conflicting. A five-year study funded by FieldTurf and published in the American Journal of Sports Medicine found that injury rates for high-school sports were similar on natural grass and synthetic turf. However, notable differences in the types of injuries were found. Athletes playing on synthetic turf sustained more skin injuries and muscle strains, while those who played on natural grass were more susceptible to concussions and ligament tears. In 2010, another FieldTurf-funded but peer-reviewed study was published in the American Journal of Sports Medicine, this time on NCAA Division I-A football, concluding that in many cases, games played on FieldTurf-branded products led to fewer injuries than those played on natural grass. However, the NFL's Injury and Safety Panel presented a study finding that anterior cruciate ligament (ACL) injuries happened 88% more often in games played on FieldTurf than in games played on grass. In 2012, the Injury and Safety Panel published an independently funded analysis of actual game data over the 2000–2009 seasons. Their statistically significant findings showed a 67% higher rate of ACL sprains and 31% higher rate of eversion ankle sprains. Uses Gridiron football The first installation of FieldTurf in the United States took place at Dick Bivins Stadium in Amarillo, Texas (which was the home field for the Amarillo Independent School District's football teams) in 1998. The first major college football installation was at University of Nebraska's Memorial Stadium in 1999. The following year, it was installed at the two Pac-10 stadiums: Martin Stadium in Pullman, Washington and Husky Stadium in Seattle. The first installation in an NFL (and by extension, professional) stadium was in 2002, at the Seattle Seahawks' new stadium, now known as Lumen Field. Originally planned to have a natural grass field, the Seahawks instead decided to install FieldTurf after they had played the two previous seasons in Husky Stadium on that surface. Association football FieldTurf's first high-profile installation came in January 1997 as English club Middlesbrough chose FieldTurf for its new training field. Only artificial fields with FIFA-recommended 2-star status can be