Distal-to-proximal progression of apophyseal injuries with age in male youth academy footballers: a two-season prospective cohort study of 16,024 player-seasons

Objectives Youth football players are vulnerable to apophyseal injuries, which can have long-term consequences for health and performance. The objective was to assess the incidence, severity and burden of apophyseal injuries among U9–U21 academy football players over two seasons. Methods Time-loss injuries and match/training exposure were tracked in male academy football players (U9–U21) from Premier League and Category One Academies. Apophyseal injuries were identified in a cohort of 16 024 player-seasons using Orchard Sports Injury Classification System (OSICS) codes, and their incidence, severity and burden were analysed. Results A total of 10 589 injuries were reported, including 603 apophyseal injuries. These injuries followed a distal-to-proximal progression with age, occurring most frequently in the ankle/foot in younger players (U9, U10 and U11), followed by the knee (U12) and hip/groin in older players (U15, U16 and U18). Across all player phases (U9–U21), injury burden (days/1000 hours) was higher in the hip/groin (3.5) and knee (3.4), compared with the ankle/foot (2.2) and pelvis/sacrum (1.4), with the highest apophyseal incidence (~0.4 injuries/1000 hours) and burden (~20 days/1000 hours) observed in the U12–U16 group, regardless of injury location. A significant trend of increasing injury severity (median days) was observed with age: U9–U11 (20), U12–U14 (29), U15–U16 (38) and U18–U21 (35). Conclusions Apophyseal injuries exhibit a distal-to-proximal progression with age, with the highest injury burden observed at the hip/groin and knee regions and in the U12–U16 group. These findings can help inform injury mitigation strategies adopted in youth academy football. No data are available. Individual data are not available upon request due to the ethics agreement terms.