Incidence, Mechanisms, and Severity of Game-Related High School Football Injuries across Artificial Turf Systems of Various Infill Weight

OBJECTIVES: Today’s new generations of artificial turf are increasingly being installed to duplicate or exceed playing characteristics of natural grass. Rather than playing on the polyethylene turf fibers, shoe: surface interaction actually occurs between the cleat and the various proprietary sand/rubber infill composites of varying weight. At this time, the influence of surface infill weight on football trauma is unknown. Therefore, this study was conducted to quantify incidence, mechanisms, and severity of game-related high school football trauma across artificial turf systems of various infill weight. METHODS: Artificial turf systems were divided into four sand/rubber infill weight groups based on lbs per square foot: (A) > 9.0, (B) 6.0 - 8.9, (C) 3.1 - 5.9 and, (D) 0.0 - 3.0. A total of 52 high schools participating across four states over 5 competitive seasons were evaluated for injury incidence, injury category, time of injury, injury time loss, player position, injury mechanism and situation, primary type of injury, injury grade and anatomical location, field location at time of injury, injury severity, head, shoulder, and lower extremity trauma, elective imaging and surgical procedures, cleat design, turf age, and environmental factors. RESULTS: Of the 1,467 high school games documented, 494 games (33.7%) were played on infill (A), 404 (27.5%) on infill (B), 379 (25.8%) on infill (C), and 190 (13.0%) on infill (D). A total of 3,741 injuries were documented, with significantly lower total injury incidence rates (IIR), [18.4 (95% CI, 18.0-18.7) vs 27.5 (26.8-27.9) vs 33.5 (32.7-34.0) and 23.7 (22.7-24.4)], substantial IIRs [3.4 (95% CI, 3.0-3.8) vs 6.6 (6.2-7.1), 8.5 (8.2-8.9) and 6.5 (5.8-7.1)], trauma from shoe: surface interaction during contact [4.6 (95% CI, 4.1-5.0) vs 7.5 (7.0-7.9), 6.4 (5.9-6.9) and 6.9 (6.2-7.5)], playing surface impact trauma [2.4 (95% CI, 2.1-2.8) vs 4.9 (4.4-5.4), 6.1 (5.6-6.6) and 4.4 (3.7-5.1)], and less total elective imaging and surgical procedures [4.6 (95% CI, 4.1-5.0) vs 7.5 (7.0-7.9), 6.4 (5.9-6.9) and 6.9 (6.2-7.5)], while competing on infill weighing >9.0 (A) versus 6.0 -8.9 (B), 3.0 - 5.9 (C), and 0.0-3.0 (D), respectively. Significantly lower trauma (P<.05) was also observed across player-to-player collisions, muscle-tendon overload, injury time loss, injury grade, skill positions, injury mechanism and situation, various cleat styles, adverse weather conditions, and turf age while competing on infill (A) when compared to infill (C). CONCLUSION: As the artificial infill surface weight decreased, the incidence of game-related high school football trauma significantly increased across numerous playing conditions. This is the first study to investigate the influence of artificial infill surface weight on the incidence of game-related high school football trauma. Since this study is in the early stages, initial findings warrant further investigation.