Analysis of lower limb injuries in collegiate American football team: a 2-year prospective study

Abstract

Collegiate American football injuries for two year seasons in Japanese Kansai Division I team were analyzed using injury rates (IR) per 1000 athlete-exposures (1000AE: one athlete-exposure was defined as a player participating in one game or one practice.), especially focusing on lower limb injuries. The overall game injury rate (GIR: 38.3) was significantly higher than practice injury rate (PIR: 13.1) (X 2 =12.355, p < 0.05). The difference between GIR in 2008 season (50.8) and in 2007 season (25.7) was significant (X 2 =8.235, p < 0.05). The lower extremity injuries approximately occupied 60% of all injuries, especially GIRs of both ankle inversion sprains (3.8) and anterior cruciate ligament (ACL: 3.3) injuries being much higher. PIR in this study was higher than the rates of collegiate American football teams in the U.S.A., especially PIRs of knee ligament injuries (ACL and medial collateral ligament injuries) and ankle sprains (inversion and eversion sprains) being much higher. Regarding the occurrence of injury, GIR with contact in ACL injuries (2.8) and GIR without contact in ankle inversion sprains (2.4) were the highest. It is also necessary to change practice plans and circumstances so that the PIR of knee and ankle injuries could be reduced. Research is needed on injury prevention for knee and ankle injuries in the games and practices.

Sports Injury Surveillance Systems and Guidelines in Japan: A Systematic Review

“…Of the 28 selected studies, five included methodological details of ISSs or ISGs developed and currently used among sports in Japan (Aim 1) 29 30 41 44 45 , whereas 23 employed and described details of ongoing ISSs or ISGs developed overseas (Aim 2) 23 24 25 26 27 28 31 32 33 34 35 36 37 38 39 40 42 43 46 47 48 49 50 .…”

“…Three of the 23 articles targeted study populations within multiple sports settings 28 31 50 , five within the rugby union 38 39 40 42 43 , four within football 25 35 36 37 , three within American football 23 46 47 , three within basketball 24 34 49 , one within lacrosse 32 , one within badminton 26 , one within baseball 48 , one within handball 33 , and one within swimming 27 . Only one of the 23 studies recorded data on professional athletes 35 , whereas the remaining studies focus on non-professional athletes (university athletes: n=17, high school athletes: n=1, junior high school athletes: n=1, elementary school athletes: n=2, and athletes ranging from junior high school to university level: n=1) 23 24 25 26 27 28 31 32 33 34 36 37 38 39 40 42 43 46 47 48 49 50 . Seven articles included data for both male and female athletes 24 26 28 31 33 49 50 , 10 described data regarding only male athletes 23 35 38 39 40 42 43 46 47…”

“…A total of four ISSs and three ISGs on injury surveillance methods were cited in 23 injury surveillance studies that were conducted in Japan: ISS 1. National Collegiate Athletic Association Injury Surveillance System [23][24][25][46][47][48][49] ISS 2. International Ski Federation Injury Surveillance System [50] ISS 3. International Olympic Committee injury surveillance system for multi-sports events [31][32][33] ISS 4. Union of European Football Associations Champions League Injury Study [26] ISG 1.…”

“…American football [23,46,47], three within basketball [24,34,49], one within lacrosse [32], one within badminton [26], one within baseball [48], one within handball [33], and one within swimming [27]. Only one of the 23 studies recorded data on professional athletes [35],…”

“…National Collegiate Athletic Association Injury Surveillance System [23][24][25][46][47][48][49] International Ski Federation Injury Surveillance System [50] International Olympic Committee injury surveillance system for multisports events [31][32][33] Union of European Football Associations Champions League Injury Study [26] Oslo Sports Trauma Research Center overuse and health problem questionnaires [27,28,34] Consensus statement on injury definitions and data collection procedures in studies of football (soccer) injuries [35][36][37] Consensus statement on injury definitions and data collection procedures for studies of injuries in rugby union [38][39][40]42-43] ▶ table 3 shows a summary of the articles that used the ISSs and ISGs developed overseas for surveillance among sports in Japan. The studies were published between 2009 and 2021.…”