Department of Kinesiology, University of New Hampshire, Durham, New Hampshire 03824, USA.
Prehosp Emerg Care. 2011 Apr-Jun;15(2):166-74. doi: 10.3109/10903127.2010.545481. Epub 2011 Feb 4.
To compare the Eject Helmet Removal (EHR) System with manual football helmet removal.
This quasiexperimental counterbalanced study was conducted in a controlled laboratory setting. Thirty certified athletic trainers (17 men and 13 women; mean ± standard deviation age: 33.03 ± 10.02 years; height: 174.53 ± 12.04 cm; mass: 85.19 ± 19.84 kg) participated after providing informed consent. Participants removed a Riddell Revolution IQ football helmet from a healthy model two times each under two conditions: manual helmet removal (MHR) and removal with the EHR system. A six-camera, three-dimensional motion capture system was used to record range of motion (ROM) of the head. A digital stopwatch was used to time trials and to record a split time associated with EHR system bladder insertion. A modified Borg CR10 scale was used to measure the rating of perceived exertion (RPE). Mean values were created for each variable. Three pairwise t-tests with Bonferroni-corrected alpha levels tested for differences between time for removal, split time, and RPE. A 2 x 3 (condition x plane) totally within-subjects repeated-measures design analysis of variance (ANOVA) tested for differences in head ROM between the sagittal, frontal, and transverse planes. Analyses were performed using SPSS (version 18.0) (alpha = 0.05).
There was no statistically significant difference in perceived difficulty between EHR (RPE = 2.73) and MHR (RPE = 2.55) (t(29) = 0.76; p = 0.45; d = 0.20). Manual helmet removal was, on average, 28.95 seconds faster than EHR (t(29) = 11.44; p < 0.001). Head ROM was greater during EHR compared with MHR in the sagittal (t(29) = 4.57; p < 0.001), frontal (t(29) = 5.90; p < 0.001), and transverse (t(29) = 8.34; p < 0.001) planes. Head ROM was also greater during the helmet-removal portion of EHR in the frontal (t(29) = 4.44; p < 0.001) and transverse (t(29) = 5.99; p < 0.001) planes, compared with MHR. Regardless of technique, sagittal-plane head ROM was greater than frontal- and transverse-plane movements (F(2,58) = 241.47; p < 0.001).
Removing a helmet manually is faster and creates slightly less motion than removing a helmet using the Eject system. Both techniques were equally easy to use. Future research should analyze the performance of the Eject system in other styles of football helmets and in helmets used in other sports such as lacrosse, motorsports, and ice hockey.
比较弹射头盔移除(EHR)系统与手动足球头盔移除。
本类实验对照研究在受控实验室环境中进行。30 名认证的运动训练师(17 名男性和 13 名女性;平均±标准差年龄:33.03±10.02 岁;身高:174.53±12.04cm;体重:85.19±19.84kg)在知情同意后参加了研究。参与者在两种情况下两次从健康模型上取下 Riddell Revolution IQ 足球头盔:手动头盔移除(MHR)和使用 EHR 系统移除。使用六相机、三维运动捕捉系统记录头部的运动范围(ROM)。使用数字秒表计时并记录与 EHR 系统膀胱插入相关的分段时间。使用改良的 Borg CR10 量表测量感知用力(RPE)的等级。为每个变量创建平均值。使用三个配对 t 检验(Bonferroni 校正的 alpha 水平)测试移除时间、分段时间和 RPE 之间的差异。2x3(条件 x 平面)完全重复测量设计方差分析(ANOVA)测试矢状面、额状面和横切面之间头部 ROM 的差异。使用 SPSS(版本 18.0)(alpha = 0.05)进行分析。
EHR(RPE = 2.73)和 MHR(RPE = 2.55)之间的感知难度没有统计学上的显著差异(t(29)=0.76;p=0.45;d=0.20)。手动头盔移除平均比 EHR 快 28.95 秒(t(29)=11.44;p<0.001)。与 MHR 相比,EHR 时矢状面(t(29)=4.57;p<0.001)、额状面(t(29)=5.90;p<0.001)和横切面(t(29)=8.34;p<0.001)的头部 ROM 更大。与 MHR 相比,EHR 头盔移除部分在额状面(t(29)=4.44;p<0.001)和横切面(t(29)=5.99;p<0.001)也有更大的头部 ROM。无论技术如何,矢状面头部 ROM 都大于额状面和横切面运动(F(2,58)=241.47;p<0.001)。
手动移除头盔比使用 Eject 系统移除头盔更快,且产生的运动略少。两种技术都同样易于使用。未来的研究应分析 Eject 系统在其他款式的足球头盔和其他运动(如曲棍球、赛车运动和冰球)中的头盔的性能。