Bussey Melanie Dawn, Davidson Peter, Salmon Danielle, Romanchuk Janelle, Tong Darryl, Sole Gisela
School of Physical Education Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand.
New Zealand Rugby, Dunedin, New Zealand.
BMJ Open Sport Exerc Med. 2022 Oct 7;8(4):e001365. doi: 10.1136/bmjsem-2022-001365. eCollection 2022.
To highlight the need for standardisation in the communication of head impact telemetry from instrumented mouthguards (iMG). The purpose of this study is to examine how the frame of reference for reporting head acceleration events (HAE) may affect the interpretation of head impacts recorded from iMGs in community rugby players.
An analytical investigation of 825 video verified HAEs recorded from male community players during 5 rugby match exposures. HAEs were captured with an iMG, known to be reliable and valid for this purpose. The linear and angular head acceleration at the centre of mass (head_CG) was calculated from filtered iMG accelerometer and gyroscope data, and the location of impact was estimated. The iMG and head_CG data were examined for systematic bias, geometric differences and the degree of concordance. Finally, mixed model analyses were fitted to assess the differences in peak resultant acceleration (PLA) by impact locations and directions of head motion while controlling for intra-athlete correlations.
The degree of concordance between the iMG versus head_CG measures varied by impact location. The mixed model confirmed differences in the PLA by location (F = 16.55, p<0.001) and by direction of head motion (F = 7.78, p<0.001).
The head acceleration reported at the iMG is not proportional to measurements that have been transformed to the head_CG. Depending on the impact location and direction of head motion, the acceleration measured at the iMG may overestimate, underestimate or miss entirely the PLA with respect to the head_CG. We recommend standardising the reporting of iMG data within the head_CG frame of reference.
强调在使用仪器化护齿（iMG）进行头部撞击遥测数据交流时标准化的必要性。本研究的目的是探讨报告头部加速度事件（HAE）的参考框架如何影响社区橄榄球运动员中iMG记录的头部撞击的解读。
对5场橄榄球比赛中男性社区球员记录的825次经视频验证的HAE进行分析调查。HAE由iMG捕获，已知其在此目的下可靠且有效。根据滤波后的iMG加速度计和陀螺仪数据计算质心（head_CG）处的线性和角向头部加速度，并估计撞击位置。检查iMG和head_CG数据的系统偏差、几何差异和一致性程度。最后，拟合混合模型分析，以评估在控制运动员内部相关性的同时，按撞击位置和头部运动方向的峰值合成加速度（PLA）差异。
iMG与head_CG测量之间的一致性程度因撞击位置而异。混合模型证实了按位置（F = 16.55，p<0.001）和头部运动方向（F = 7.78，p<0.001）的PLA差异。
iMG报告的头部加速度与转换到head_CG的测量值不成比例。根据撞击位置和头部运动方向，iMG测量的加速度相对于head_CG可能高估、低估或完全错过PLA。我们建议在head_CG参考框架内对iMG数据的报告进行标准化。
