Stockwell David W, Blalock Richard, Podell Kenneth, Marco Rex A W
Department of Neurological Surgery, School of Medicine, Indiana University, Indianapolis, Indiana, USA.
Murray-Calloway County Hospital, Murray, Kentucky, USA.
Orthop J Sports Med. 2020 Feb 19;8(2):2325967120902714. doi: 10.1177/2325967120902714. eCollection 2020 Feb.
In American football, fewer fatalities and severe injuries have been seen annually since 1976, after data from 1971 through 1975 were retrospectively reviewed to better understand the mechanisms involved in catastrophic cervical spine injury and rules were enacted to prohibit certain types of aggressive tackling. The National Football Head and Neck Injury Registry was established in 1975.
To assess (1) tackling techniques that coaches were teaching at 3 levels-youth level (YL; 4th to 5th grades), middle school (MS; 6th to 8th grades), and high school (HS; 9th to 12th grades); (2) tackling techniques used during games; and (3) the successful tackle rates of these techniques.
Descriptive epidemiology study.
Surveys were distributed via email to 500 coaches of YL, MS, and HS football teams in Texas. Coaches provided video recordings of football games, and all tackle attempts were graded by a single reviewer who watched game videos; 1000 consecutive tackles were observed for each group. Survey data included how coaches instructed their players to tackle, the types of tackles, the number of tackles versus missed tackles, the head position, and the initial contact. Data were analyzed with the chi-square test. A subset of 100 consecutive tackles at each level of play was reviewed by 2 blinded reviewers to assess intra- and interrater reliabilities.
In all groups, coaches responded that they preferred to teach the at-risk "head across the bow" tackling technique (83% YL, 81% MS, 75% HS). Coaches stated that they instructed players to "keep your head up," as currently recommended, 89% in YL, 100% in MS, and 81% in HS. During games, players used head-up, inside-shoulder tackles more successfully across all groups (97.5% YL, 99.5% MS, 98.8% HS). While intra- and interrater reliabilities were in the good range, these scores were lower in the youth group.
Our study supports the effectiveness of tackling with the head up and making the initial contact with the inside shoulder. Lower reliability ratings for the youth group were likely due to lower video quality and the lack of players' tackling experience.
在美国橄榄球运动中,自1976年以来,每年的死亡和重伤人数有所减少。此前对1971年至1975年的数据进行了回顾性研究,以更好地了解灾难性颈椎损伤的机制,并制定了规则禁止某些类型的攻击性擒抱动作。国家橄榄球头部和颈部损伤登记处成立于1975年。
评估(1)教练在三个级别(青少年组(YL;四年级至五年级)、初中组(MS;六年级至八年级)和高中组(HS;九年级至十二年级))所教授的擒抱技术;(2)比赛中使用的擒抱技术;(3)这些技术的成功擒抱率。
描述性流行病学研究。
通过电子邮件向德克萨斯州500名青少年组、初中组和高中组橄榄球队的教练发放调查问卷。教练提供橄榄球比赛的视频记录,所有擒抱尝试均由一名观看比赛视频的评审员进行评分;每组观察1000次连续擒抱。调查数据包括教练如何指导球员进行擒抱、擒抱类型、擒抱次数与未成功擒抱次数、头部位置以及初始接触部位。数据采用卡方检验进行分析。每个比赛级别连续100次擒抱的子集由两名盲法评审员进行审查,以评估评分者内信度和评分者间信度。
在所有组中,教练表示他们更喜欢教授有风险的“头部横过船头”擒抱技术(青少年组83%、初中组81%、高中组75%)。教练表示,他们按照目前的建议指导球员“抬起头”,青少年组为89%,初中组为100%,高中组为81%。在比赛中,所有组中球员使用抬头、内侧肩部擒抱的成功率更高(青少年组97.5%、初中组99.5%、高中组98.8%)。虽然评分者内信度和评分者间信度处于良好范围,但青少年组的这些分数较低。
我们的研究支持抬头擒抱并以内侧肩部进行初始接触的有效性。青少年组较低的信度评分可能是由于视频质量较低以及球员缺乏擒抱经验。