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Background: Although data exist on injuries in youth football leagues, there are limited recent data on injury incidence in middle school football. Updated injury incidence estimates can help drive the development of injury prevention strategies. Purpose: Describe the epidemiology of injuries in middle school football during school years 2015-2016 to 2017-2018. Study Design: Descriptive epidemiology study. Methods: Data originated from 9 public middle schools in Virginia during school years 2015-2016 to 2017-2018. Certified athletic trainers collected injury and athlete-exposure (AE) data from school-sanctioned games and practices in boys’, football. Injury counts and rates per 1000 AEs were calculated. Injury rate ratios with 95% CIs compared rates between games and practices. Results: Overall, 664 middle school boys’, football injuries were reported, leading to an overall injury rate of 20.54 per 1000 AEs (95% CI, 18.98-22.11). The time loss injury rate (inclusive of injuries with participation restriction time ≥24 hours) was 9.28 per 1000 AEs (95% CI, 8.23-10.33). The injury rate was higher in competition than practice (36.19 vs 17.97 per 1000 AEs; injury rate ratio, 2.01; 95% CI, 1.69-2.40). Most injuries were to the head/face (competition, 20.6%; practice, 15.8%) and hand/wrist (competition, 18.8%; practice, 16.4%) and were diagnosed as contusions (competition, 30.9%; practice, 25.9%) and sprains (competition, 19.4%; practice, 12.6%). Competitions also had a large proportion of concussions (10.3%). Overall, 80.0% and 66.9% of injuries were due to contact in competition and practice, respectively; of these contact-related injuries, 62.1% and 41.6% were specifically player contact. Conclusion: Injury distributions parallel those found in previous research from middle school and other sport settings. Injury rates in middle school football were higher than those reported in previous findings in high school and college. However, caution must be taken when interpreting findings in relation to other surveillance systems with varying methodologies. Still, the findings highlight the need for injury prevention strategies within middle school football, particularly as related to contact-related mechanisms.

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Gait modification using real-time biofeedback is a conservative intervention associated with positive outcomes. Results from systematic reviews corroborate the effectiveness of various strategies employing real-time biofeedback for reducing estimated knee joint load. The effects on the nonmodified limb, however, remain unclear. Biomechanical changes to the nonmodified limb were investigated during unilaterally implemented medial knee thrust, lateral trunk lean, and toe-in foot progression. Nineteen healthy participants were recruited. Ten trials were completed for each gait condition including baseline. Assigned magnitude for each gait modification strategy was individualized based on the mean and SD of the gait parameter during baseline. Visual real-time biofeedback was provided. During medial knee thrust, participants’ nonmodified limb presented with increased: first peak medial knee contact force, internal first peak knee extensor moment, as well as knee- and hip-flexion angles at internal first peak knee extensor moment. Observed biomechanical changes are elucidative of the body’s attempt to attenuate increased external loads. These findings may carry significant implications for pathological populations. Load redistribution to the nonmodified side may result in unfavorable long-term outcomes particularly in patients with bilateral diagnosis. Future studies should explore acute and chronic changes in the nonmodified limb of individuals with knee osteoarthritis.

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