England Rory, Haynes Marina, Mee Harry, Farmer Jon
Sports Technology Institute, Woldson School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
Division of Rehabilitation Medicine, Department of Clinical Neurosciences, University of Cambridge and Cambridge University Hospital, Cambridge, United Kingdom.
Front Bioeng Biotechnol. 2025 Apr 16;13:1575075. doi: 10.3389/fbioe.2025.1575075. eCollection 2025.
Medical helmets (MHs) are used by individuals with an increased vulnerability to falls and are essentially unregulated in the UK; therefore, their impact performance is unproven. This study investigated the performance of a selection of medical helmets available to clinicians using general techniques to determine their protective performance against impacts. Additionally, clinicians have stated that medical helmets need to consider focal vulnerabilities to impact (often a postsurgical site of a decompressive craniectomy); therefore, novel techniques were specifically employed for measuring the protection of a focal site.
A freefall drop test methodology was used to assess six medical helmets (MH1-6) and two sports helmets (SH1 and SH2). The headform was instrumented with six degrees of freedom instrumentation to quantify global kinematics metrics related to injury risk (peak linear acceleration (PLA), peak angular velocity (PAV), peak angular acceleration (PAA), head injury criterion (HIC), and brain injury criterion (BrIC)), and a thin-film contact pressure measurement system was used to quantify the contact area (above a threshold of 560 kPa) focal to the impact. Due to the advanced nature of these measurements, a novel biofidelic headform was used to more accurately represent local deformation. Additionally, impact performance was plotted against two proxy measures of comfort.
The difference in performance between the worst and best helmets ranged from 90% to 2844%, showing a substantial variation. HIC, PLA, and PAA showed the largest range, whereas PAV showed the smallest range. Nonetheless, there was good agreement between each kinematic metric regarding the rank order of the medical helmets. The contact pressure was a consistent outlier. Each metric included at least one injury threshold, which MH4 and MH6 consistently exceeded (15/18 occasions).
MH2 and MH3 were the only medical helmets comparable to sports helmets in terms of both comfort and performance. MH1 showed excellent performance metrics but exhibited possible discomfort, while MH4 was above average across both measurement categories. MH4 and MH6 were significantly deficient compared to the sample of helmets. These results highlight the need for standardisation.
医疗头盔（MHs）供那些跌倒风险增加的人使用，在英国基本上不受监管；因此，其撞击性能未经证实。本研究使用通用技术调查了临床医生可获得的一系列医疗头盔的性能，以确定它们对撞击的防护性能。此外，临床医生表示，医疗头盔需要考虑撞击的局部易损部位（通常是减压颅骨切除术后的手术部位）；因此，专门采用了新技术来测量局部部位的防护情况。
采用自由落体跌落测试方法评估六种医疗头盔（MH1 - 6）和两种运动头盔（SH1和SH2）。头模配备了六自由度仪器，以量化与损伤风险相关的整体运动学指标（峰值线性加速度（PLA）、峰值角速度（PAV）、峰值角加速度（PAA）、头部损伤标准（HIC）和脑损伤标准（BrIC））；并且使用薄膜接触压力测量系统来量化撞击部位的接触面积（高于560kPa的阈值）。由于这些测量的先进性，使用了一种新型生物逼真头模来更准确地表示局部变形。此外，绘制了撞击性能与两种舒适度替代指标的关系图。
最差和最佳头盔之间的性能差异在90%至2844%之间，显示出很大的差异。HIC、PLA和PAA的差异范围最大，而PAV的差异范围最小。尽管如此，就医疗头盔的排名顺序而言，各运动学指标之间存在良好的一致性。接触压力始终是一个异常值。每个指标都至少有一个损伤阈值，MH4和MH6始终超过该阈值（18次中有15次）。
就舒适度和性能而言，MH2和MH3是仅有的与运动头盔相当的医疗头盔。MH1表现出优异的性能指标，但可能存在不适感，而MH4在两个测量类别中均高于平均水平。与头盔样本相比，MH4和MH6明显不足。这些结果凸显了标准化的必要性。
