School of Psychological Sciences, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia.
Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL, USA.
Sports Med. 2022 Sep;52(9):2221-2245. doi: 10.1007/s40279-022-01683-2. Epub 2022 May 6.
Investigators have proposed that various physical head and neck characteristics, such as neck strength and head and neck size, are associated with protection from mild traumatic brain injury (mTBI/concussion).
To systematically review the literature and investigate potential relationships between physical head and neck characteristics and mTBI risk in athletic and military populations.
A comprehensive search of seven databases was conducted: MEDLINE, EMBASE, CINAHL, Scopus, SPORTDiscus, Cochrane Library, and Web of Science. Potential studies were systematically screened and reviewed. Studies on military and athletic cohorts were included if they assessed the relationship between physical head-neck characteristics and mTBI risk or proxy risk measures such as head impact kinematics.
The systematic search yielded a total of 11,723 original records. From these, 22 studies met our inclusion criteria (10 longitudinal, 12 cross-sectional). Relevant to our PECO (Population, Exposure, Comparator, and Outcomes) question, exposures included mTBI incidence and head impact kinematics (acceleration, velocity, displacement) for impacts during sport play and training and in controlled laboratory conditions. Outcome characteristics included head and neck size (circumference, mass, length, ratios between these measures), neck strength and endurance, and rate of force development of neck muscles.
We found mixed evidence for head and neck characteristics acting as risk factors for and protective factors against mTBI and increased susceptibility to head impacts. Head-neck strength and size variables were at times associated with protection against mTBI incidence and reduced impact kinematics (14/22 studies found one or more head-neck variable to be associated with protection); however, some studies did not find these relationships (8/22 studies found no significant associations or relationships). Interestingly, two studies found stronger and larger athletes were more at risk of sustaining high impacts during sport. Strength and size metrics may have some predictive power, but impact mitigation seems to be influenced by many other variables, such as behaviour, sex, and impact anticipation. A meta-analysis could not be performed due to heterogeneity in study design and reporting.
There is mixed evidence in the literature for the protective capacity of head and neck characteristics. We suggest field-based mTBI research in the future should include more dynamic anthropometric metrics, such as neck stiffness and response to perturbation. In addition, laboratory-based mTBI studies should aim to standardise design and reporting to help further uncover these complicated relationships.
研究人员提出，颈部力量和头颈部大小等各种头部和颈部物理特征与轻度创伤性脑损伤（mTBI/脑震荡）的保护有关。
系统回顾文献，调查运动和军事人群中头部和颈部物理特征与 mTBI 风险之间的潜在关系。
对 MEDLINE、EMBASE、CINAHL、Scopus、SPORTDiscus、Cochrane 图书馆和 Web of Science 这七个数据库进行了全面搜索。系统筛选和审查了潜在的研究。如果研究评估了头颈部物理特征与 mTBI 风险或头部冲击运动学等替代风险指标之间的关系，或者研究对象为军事和运动队列，则纳入研究。
系统搜索共产生了 11723 条原始记录。从中，有 22 项研究符合我们的纳入标准（10 项纵向研究，12 项横断面研究）。与我们的 PECO（人群、暴露、对照和结局）问题相关，暴露包括运动和训练中的 mTBI 发生率和头部冲击运动学（加速度、速度、位移），以及在受控实验室条件下。结局特征包括头颈部大小（周长、质量、长度、这些测量值之间的比值）、颈部力量和耐力，以及颈部肌肉的力发展率。
我们发现，头部和颈部特征作为 mTBI 和头部冲击易感性增加的危险因素和保护因素的证据参差不齐。头颈部力量和大小变量有时与 mTBI 发生率和减少的冲击运动学有关（22 项研究中有 14 项发现一个或多个头颈部变量与保护有关）；然而，有些研究没有发现这些关系（22 项研究中有 8 项没有发现显著关联或关系）。有趣的是，有两项研究发现，更强壮和更大的运动员在运动中更有可能承受高冲击。力量和大小指标可能具有一定的预测能力，但冲击缓解似乎受到许多其他变量的影响，例如行为、性别和冲击预期。由于研究设计和报告存在异质性，因此无法进行荟萃分析。
文献中关于头部和颈部特征的保护能力的证据参差不齐。我们建议未来的基于现场的 mTBI 研究应包括更多动态人体测量学指标，例如颈部刚度和对扰动的反应。此外，基于实验室的 mTBI 研究应旨在标准化设计和报告，以帮助进一步揭示这些复杂的关系。
