Incidence of Game-Related, High School Football Lower Extremity and Surface Impact Trauma Requiring Elective Imaging and Surgery across Artificial Turf Systems of Various Infill Weight

OBJECTIVES: Artificial turf surfaces are developed to duplicate playing characteristics of natural grass. With the newer generations of sand and rubber infill systems, infill weight is a common component that varies between fields. With the increasing concerns of rising medical costs, the potential for long-term articular changes, and perceived higher incidence of articular trauma while playing on artificial turf, infill weight could be a critical factor that could influence sport trauma and subsequent elective medical decisions. Therefore, this study quantified the incidence of game-related, high school football lower extremity and surface impact trauma requiring elective medical procedures across artificial turf systems of various infill weight. METHODS: Artificial turf systems were divided into two sand/rubber infill weight groups by lbs per square foot: 6.0 to ≥9.0, and 0.0-5.9. Fifty-seven high schools participated across four states over 5 seasons. Outcomes of interest included elective medical procedures by injury category (player-turf surface impact trauma, trauma from shoe: surface interaction during physical collision/contact, trauma from shoe: surface interaction during physical noncontact). Data were subject to multivariate analyses of variance (MANOVA) and Wilks’ λ criteria using general linear model procedures. RESULTS: Of 1,837 games documented, 1,049 games were played on 6.0 to ≥9.0 lbs infill/sq. ft, and 788 on 0.0-5.9 lbs infill/sq. ft, with 4,655 total injuries reported. MANOVA indicated a significant main effect across elective medical procedures by injury category (F3,3977 = 16.574; P < .0001). Post hoc analyses indicated significantly lower injury incidence rates (IIR per 10 game season) requiring radiography and MRI procedures following player-turf surface impact trauma [1.7, (95% CI, 1.5 -1.9) vs 3.2 (2.9-3.5); P = .001], trauma from shoe: surface interaction during physical collision/contact [2.4, (95% CI, 2.1-2.6) vs 3.2 (2.9-3.5); P = .001], and trauma from shoe: surface interaction during physical noncontact [0.4, (95% CI, 0.3-0.5) vs 0.7 (0.5-0.9); P = .01], while competing on the 6 to ≥9.0 lbs infill/sq. ft when compared to the lighter infill weight systems, respectively. No significant differences in surgical procedures by injury category were observed between infill weight. CONCLUSION: As the artificial infill surface weight decreased, the incidence of game-related, high school football lower extremity and surface impact trauma, and subsequent elective medical procedures significantly increased. Based on findings, high school football fields should minimally contain 6.0 to ≥9.0 lbs infill/sq. ft. This is the first longitudinal study to investigate the influence of artificial infill weight influence on high school sport trauma and elective medical decisions.