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Ballistic helmets are an important part of personal protective equipment in war and are specifically designed to protect a person's head. The future trend is to improve the protective performance of helmets through the use of lightweight coatings, and polyurea, as one of the hottest elastomeric polymer coating materials in recent years, has excellent physical properties, especially its ability to improve the target's protection against blast shock waves. Therefore, in this study, using a validated head model, a blast impact model under the fluid-solid coupling method was constructed to study the effect of blast wave on the model and to analyse its effect on intracranial pressure and skull deformation. In addition, the effect of the position of the polyurea lightweight protective coating on the bending deformation of the skull under the effect of the blast wave was also investigated. The results showed that the polyurea coating could reduce the skull deformation under the same surface density condition. However, spraying polyurea on the blast surface of the helmet's blast-facing surface does not effectively reduce skull deformation caused by blast waves.

Boxing is a popular combat sport in which participants frequently experience head trauma. The neurological impact of boxing has been widely discussed, but the impact on the bone and soft tissue of the head has been less investigated. For this study, a national emergency department database was used to investigate the impact of a 2013 rule change - removing the requirement for amateurs to wear head protection - on the frequency and type of facial injuries sustained by amateur boxers. Over the study period (2006-2021) there were 11 760 injuries, with 6261 occurring before the change and 5499 occurring after (p < 0.001). The number of contusions, fractures, hematomas, and hemorrhages all significantly decreased after the rule change, while the number of lacerations did not. Additionally, the number of septal deviations increased from 16 to 97 (p < 0.001). According to age-group-specific analysis, injuries decreased in both the 0-17 and 24-29 cohorts, but increased in the 18-23 group. The results suggest that the rule change may have had a protective effect on the risk of craniofacial trauma in amateur boxers, potentially due to increased risk-averse behavior by the boxers, who may feel less protected during sparring because of the lack of head protection., Competing Interests: Declaration of competing interest None., (Copyright © 2024 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Different surgical techniques have been explored over time to treat children with scaphocephaly. The objective of this study is to compare morbidity and cosmetic outcomes in total cranial vault remodelling (TCVR) and minimally invasive suturectomy with postoperative helmet therapy (MISPH) in patients with scaphocephaly. The authors performed a retrospective comparative cohort study, including 43 patients with isolated sagittal craniosynostosis who underwent TCVR (n=17) or MISPH (n=26) at the Antwerp University Hospital between April 2008 and December 2022. MISPH was associated with significantly shorter procedure duration (TCVR 199 ± 48 min, MISPH 69 ± 12 min, P <0.001), decreased blood loss (TCVR 610 ± 298 mL, MISPH 85 ± 73 mL, P <0.001) and lower transfusion rate (TCVR 100%, MISPH 54%, P <0.001). Mean length of stay at the intensive care unit and the hospital were significantly shorter after MISPH (TCVR 6 ± 1 d, MISPH 3 ± 0.5 d). The change in CI after TCVR was significantly larger than after MISPH during the first postoperative year. However, the CI in the MISPH group was significantly higher during the first year compared with the TCVR group. Mean CI of the MISPH group reached normal limits during the first year, while in the TCVR group, mean CI reached normal values 5 years after surgery. The authors could not find a statistically significant difference in cosmetic outcome between the 2 groups. The authors conclude that MISPH is associated with decreased morbidity and comparable cosmetic results when compared with TCVR in the treatment of scaphocephaly., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 by Mutaz B. Habal, MD.)

Craniosynostosis limits normal cranial growth, significantly affecting the growth and development of children. This increase in intracranial pressure results in significant cosmetic and functional losses. This study investigated the efficacy of combining molding helmets with suturectomy for craniosynostosis. Patients who underwent suturectomy and molding helmet therapy for craniosynostosis at a single institution between 2017 and 2024 were included. Changes in cephalic index (CI) and cranial vault asymmetry index (CVAI) were analyzed. A total of 14 patients (12 males, 2 females) were included, with a median age of 4.5 months (2-6 mo). The affected sutures were as follows: sagittal (n=8), bilateral coronal (n=4), unilateral coronal (n=1), and lambdoid (n=1) sutures. The median duration of postoperative molding helmet therapy was 44.5 weeks. For the sagittal suture group, the median preoperative CI, median postoperative CI, and rate of change were 72.0 (68.3-85.8), 77.0 (72.1-86.4), and 0.0646, respectively. For the bilateral coronal suture group, measurements for the same parameters were 104.0 (99.3-110.0), 92.5 (89.1-94.5), and 0.1114, respectively. For the unilateral coronal group, the measured parameters were 89.0 (87.7-91.2), 84.0 (81.2-87.1), and 0.059, respectively. Although all suture types showed improvement in cranial shape, with sagittal synostosis showing the most significant change, our findings did not support the added benefit of molding helmet therapy. Overall, the study suggests that suturectomy is a crucial first step in craniosynostosis treatment, leading to improvements in cranial morphology and growth., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 by Mutaz B. Habal, MD.)

Introduction: Fall-induced traumatic brain injury (TBI) is considered one of the most serious occupational injuries in construction. Given the frequency of falls from ladders, knowledge of head kinematics during ladder falls to the ground may help inform any potential improvement to construction safety helmet design and improve their protection against head injury. Therefore, the goal of this descriptive study was to measure head kinematics during laboratory-induced ladder falls to the ground., Method: Eighteen young adults wearing a hockey helmet simulated construction tasks that challenged their balance while standing on stepladders and an extension ladder with their feet at heights up to 1.8 m above padding covering the ground. Falls onto the padding occurred spontaneously or were induced by an investigator nudging the ladder to simulate ladder movement resulting from the ground shifting. Optoelectronic motion capture was used to capture head kinematics up to the instant immediately before head impact., Results: Of 115 total falls, 15 involved head impact with the padding and were analyzed. Head impact during all 15 of these falls occurred on the back of the head. Immediately before impact with the padding, head vertical velocity ranged from 0.42 to 3.88 m/s and head angular velocity about a medial-lateral axis ranged from 60.1 to 1215.5 deg/s., Conclusions: These data can be used with computer simulations or headform impact testing to estimate true head impact kinematics, or to inform future versions of construction safety helmet testing standards., Practical Applications: This is the first study we are aware of to capture head kinematics of human subjects during ladder falls to the ground. These results have the potential to inform future versions of construction safety helmet testing standards and contribute to improved helmet design for protection against fall-induced head injury., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Ltd.)

Bicycle helmets are designed to protect against skull fractures and associated focal brain injuries, driven by helmet standards. Another type of head injury seen in injured cyclists is diffuse brain injuries, but little is known about the protection provided by bicycle helmets against these injuries. Here, we examine the performance of modern bicycle helmets in preventing diffuse injuries and skull fractures under impact conditions that represent a range of real-world incidents. We also investigate the effects of helmet technology, price, and mass on protection against these pathologies. 30 most popular helmets among UK cyclists were purchased within 9.99-135.00 GBP price range. Helmets were tested under oblique impacts onto a 45° anvil at 6.5 m/s impact speed and four locations, front, rear, side, and front-side. A new headform, which better represents the average human head's mass, moments of inertia and coefficient of friction than any other available headforms, was used. We determined peak linear acceleration (PLA), peak rotational acceleration (PRA), peak rotational velocity (PRV), and BrIC. We also determined the risk of skull fractures based on PLA (linear risk), risk of diffuse brain injuries based on BrIC (rotational risk), and their mean (overall risk). Our results show large variation in head kinematics: PLA (80-213 g), PRV (8.5-29.9 rad/s), PRA (1.6-9.7 krad/s 2 ), and BrIC (0.17-0.65). The overall risk varied considerably with a 2.25 ratio between the least and most protective helmet. This ratio was 1.76 for the linear and 4.21 for the rotational risk. Nine best performing helmets were equipped with the rotation management technology MIPS, but not all helmets equipped with MIPS were among the best performing helmets. Our comparison of three tested helmets which have MIPS and no-MIPS versions showed that MIPS reduced rotational kinematics, but not linear kinematics. We found no significant effect of helmet price on exposure-adjusted injury risks. We found that larger helmet mass was associated with higher linear risk. This study highlights the need for a holistic approach, including both rotational and linear head injury metrics and risks, in helmet design and testing. It also highlights the need for providing information about helmet safety to consumers to help them make an informed choice., Competing Interests: Declarations Conflict of interest No authors have conflicts of interest to declare., (© 2024. The Author(s).)

The blast shock waves generated by the explosion are severe threat to soldiers on the battlefield, while the helmets currently equipped for the soldiers cannot offer sufficient blast protection. Some helmet pads have been developed to improve the protection performance of the combat helmets against shock waves. However, it remains unclear how to design the helmet pads to protect the head more effectively against blast shock waves. This study aims to design a new mechanics-guided helmet pad and evaluate its protection performance by numerical simulations. The design of the new helmet pad is guided by the oblique reflection theory (ORT), and the advanced combat helmet (ACH) pad is applied for comparison. The protection performance of the pads against blast waves from two directions (frontal and lateral) was investigated. The differences in the distributions of overpressure inside the helmet using two types of pads were analyzed, and the intracranial pressure (ICP) of head was compared. The ORT-guided pads can reduce the overpressure inside the helmet, minimizing the possibility of blast-induced traumatic brain injury. Furthermore, the underwash phenomenon can also be controlled when the new pads are applied. The results in this study provide an important theoretical basis and some guidelines on the design of helmet pads for the protection of human brain from blast shock waves., (© 2024 John Wiley & Sons Ltd.)

Purpose: With the growing technical options of power transmission and energy-saving options in electric drives, the number of E-bike-related accidents especially in an elderly population has increased. The aim of the current study was to compare if the increased velocity in comparison to conventional bikes translates into different injury patterns in the cranio-cervical and head region., Methods: A retrospective cohort study was performed in patients admitted to our level one trauma center between 2009 and 2019 after being involved in an accident with either an E-bike, bicycle, or motorcycle and suffered cranio-cervical or traumatic brain injury., Outcomes: cranio-cervical/intracranial injury pattern. Data interpretation was conducted in an interdisciplinary approach., Results: From 3292 patients treated in this period, we included 1068 patients. E-bikers were significantly older than bicyclists (or motorcyclists) and lay between the other two groups in terms of helmet use. Overall injury patterns of E-bikers resembled those found in motorcyclists rather than in bicyclists. E-bikers had a higher incidence of different cerebral bleedings, especially if no helmet was worn. Helmet protection of E-bikers resulted in a comparable frequency of intracranial bleeding to the helmeted bicyclists., Conclusion: The overall pattern of head and cervical injuries in E-bikers resembles more to that of motorcyclists than that of bicyclists. As they are used by a more senior population, multiple risk factors apply in terms of complications and secondary intracranial bleeding. Our study suggests that preventive measures should be reinforced, i.e., use of helmets to prevent from intracranial injury., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

This study aims to explore the effects of helmet structure designs and wearing modes on the protective performance of safety helmets under the impact of falling objects. Four helmet types (no helmet, V-shaped, dome-shaped, and motorcycle helmets) and five wearing modes (left and right tilt by 5 deg, backward tilt by 15 deg, 0 deg without chin strap, 0 deg with chin strap) were included in this study. The axial impact of a concrete block under various impact velocities was simulated. The results indicate that the energy absorption and shock mitigation effects of the foam cushion are superior to those of the suspension system in traditional industrial safety helmets. The structure of the top of V-shaped helmets is designed to withstand greater impact. Regarding the wearing mode, the helmet strap's deflection angle increases stress in the brain tissue and skull, heightens intracranial pressure, and causes pressure diffusion toward the forehead., (Copyright © 2024 by ASME.)

Traumatic brain injury (TBI) in cyclists is a growing public health problem, with helmets being the major protection gear. Finite element head models have been increasingly used to engineer safer helmets often by mitigating brain strain peaks. However, how different helmets alter the spatial distribution of brain strain remains largely unknown. Besides, existing research primarily used maximum principal strain (MPS) as the injury parameter, while white matter fiber tract-related strains, increasingly recognized as effective predictors for TBI, have rarely been used for helmet evaluation. To address these research gaps, we used an anatomically detailed head model with embedded fiber tracts to simulate fifty-one helmeted impacts, encompassing seventeen bicycle helmets under three impact locations. We assessed the helmet performance based on four tract-related strains characterizing the normal and shear strain oriented along and perpendicular to the fiber tract, as well as the prevalently used MPS. Our results showed that both the helmet model and impact location affected the strain peaks. Interestingly, we noted that different helmets did not alter strain distribution, except for one helmet under one specific impact location. Moreover, our analyses revealed that helmet ranking outcome based on strain peaks was affected by the choice of injury metrics (Kendall's Tau coefficient: 0.58-0.93). Significant correlations were noted between tract-related strains and angular motion-based injury metrics. This study provided new insights into computational brain biomechanics and highlighted the helmet ranking outcome was dependent on the choice of injury metrics. Our results also hinted that the performance of helmets could be augmented by mitigating the strain peak and optimizing the strain distribution with accounting the selective vulnerability of brain subregions and more research was needed to develop region-specific injury criteria., Competing Interests: Declarations. Conflict of Interest: MF is employed by Mips AB. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024. The Author(s).)

Purpose: The study purpose was to investigate the laboratory-based performance of three commercially available shell add-on products under varsity-level impact conditions., Methods: Pendulum impact tests were conducted at multiple locations (front, front boss, rear, side) and speeds (3.1, 4.9, 6.4 m/s) using two helmet models. Tests were performed with a single add-on configuration for baseline comparisons and a double add-on configuration to simulate collisions with both players wearing shell add-ons. A linear mixed-effect model was used to evaluate peak linear acceleration (PLA), peak rotational acceleration (PRA), and concussion risk, which was calculated from a bivariate injury risk function, based on shell add-on and test configuration., Results: All shell add-ons decreased peak head kinematics and injury risk compared to controls, with the Guardian NXT producing the largest reductions (PLA: 7.9%, PRA: 14.1%, Risk: 34.1%) compared to the SAFR Helmet Cover (PLA: 4.5%, PRA: 9.3%, Risk: 24.7%) and Guardian XT (PLA: 3.2%, PRA: 5.0%, Risk: 15.5%). The same trend was observed in the double add-on test configuration. However, the Guardian NXT (PLA: 17.1%; PRA: 11.5%; Risk: 62.8%) and SAFR Helmet Cover (PLA: 12.2%; PRA: 9.1%; Risk: 52.2%) produced larger reductions in peak head kinematics and injury risk than the Guardian XT (PLA: 5.7%, PRA: 2.2%, Risk: 21.8%)., Conclusion: In laboratory-based assessments that simulated varsity-level impact conditions, the Guardian NXT was associated with larger reductions in PLA, PRA, and injury risk compared to the SAFR Helmet Cover and Guardian XT. Although shell add-ons can enhance head protection, helmet model selection should be prioritized., (© 2024. The Author(s).)

This study explores the effectiveness of architected lattice structures, specifically made of polyamide 12 (PA12) material, as potential helmet liners to mitigate traumatic brain injuries (TBI), with a focus on rotational acceleration. Evaluating three lattice unit cell topologies (simple cubic, dode-medium, and rhombic dodecahedron), the research builds upon prior investigations indicating that PA12 lattice liners may outperform conventional EPS liners. Employing a high-fidelity finite element male head model and utilizing direct and oblique impact scenarios, mechanical quantities, such as maximum principal strain (MPS) and shear strain, cumulative strain damage measure and intracranial pressure were measured at the tissue level in different brain regions. Results indicate that lattice liners, especially with dode-medium topology, exhibit promising reductions in brain tissue strains. On average, during oblique impacts, less than 1 % of the brain volume experienced an MPS level of 0.4 when the lattice liners were adopted, whereas that percentage was above 70 % with the expandable polystyrene (EPS) foam liners. Pressure-based assessments suggest that lattice liners may outperform EPS liners in oblique impacts, showcasing the limitations of EPS for effective TBI mitigation. Despite certain model limitations, this study emphasizes the need for advancements in helmet technology, particularly in the development of commercial lattice liners using additive manufacturing, to address the limitations of existing EPS liners in preventing rotational consequences of impacts and reducing TBI., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This study investigates the risk of head injuries, specifically concussions, from falling objects in workplace accidents. A case study focuses on a construction worker who sustained a head injury despite wearing a protective helmet. Utilizing finite element (FE) analysis, the helmet-head system was modeled to assess impact forces and head accelerations. The helmet, made of High-Density Polyethylene with a 6-point suspension system, was tested against falling objects of 332 g and 665 g. Simulations, conducted from heights of 5 to 25 m, revealed that objects weighing as little as 332 g could cause severe concussions from a 10-meter fall. These findings demonstrate that helmets, while mitigating some impact, absorb significantly less energy than the kinetic energy of falling objects. The analyses carried out confirmed the worker's statement that his injury was caused by a foreign object falling on his head, which was protected by a helmet., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The assessment of cervical intervertebral kinematics can serve as the basis for understanding any degenerative changes in the cervical spine due to the prolonged wear of a heavyweight, imbalanced firefighting helmet. Therefore, this study aimed to analyze cervical intervertebral kinematics using the OpenSim musculoskeletal modeling platform in order to provide much-needed insights into how the inertial properties of firefighter helmets affect cervical spinal mobility. A total of 36 firefighters (18 males and 18 females) were recruited to perform static and dynamic neck flexion, extension, and left and right lateral bending tasks for three conditions: 1) no-helmet, 2) US-style helmet with a comparatively superior center of mass (COM), and 3) European-style helmet with relatively higher mass but an inferior COM. Three custom-made OpenSim head-neck models were created to calculate cervical intervertebral kinematics for each helmet condition. Results showed that helmet use significantly (p < 0.001) affects neck and cervical spinal kinematics. Despite its lighter weight, the superior COM placement in the US-style helmet caused more pronounced angular changes and higher velocity of peak flexion and extension angles compared to the European-style helmet across all cervical joints. Moreover, results revealed discrepancies between OpenSim-derived neck and cervical range-of-motion and those reported in previous in-vivo studies. In conclusion, the present study underscores the importance of designing firefighter helmets with a lower profile (less superior COM) to enhance neck range of motion and minimize potential neck injuries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This paper presents significant improvements in the accuracy and computational efficiency of safety helmet detection within industrial environments through the optimization of the you only look once version 5 small (YOLOv5s) model structure and the enhancement of its loss function. We introduce the convolutional block attention module (CBAM) to bolster the model's sensitivity to key features, thereby enhancing detection accuracy. To address potential performance degradation issues associated with the complete intersection over union (CIoU) loss function in the original model, we implement the modified penalty-decay intersection over union (MPDIoU) loss function to achieve more stable and precise bounding box regression. Furthermore, considering the original YOLOv5s model's large parameter count, we adopt a lightweight design using the MobileNetV3 architecture and replace the original squeeze-and-excitation (SE) attention mechanism with CBAM, significantly reducing computational complexity. These improvements reduce the model's parameters from 15.7 GFLOPs to 5.7 GFLOPs while increasing the mean average precision (mAP) from 82.34% to 91.56%, demonstrating its superior performance and potential value in practical industrial applications.

It was the aim of the study to analyze the distribution and pattern of facial fractures following e-scooter trauma. Prospective audit data of facial fractures were retrospectively collected to investigate the impact of e-scooter hire, specifically in the form of facial fractures associated with their use. Data collected included patient demographics, mode of injury, date of injury, facial bones involved, presence of soft tissue injury, and factors associated with injury, including intoxication and helmet use. A total of 849 patients were treated for facial fractures during the study period, of which 34 were attributed to e-scooter use. One-half of those injured riding e-scooters were intoxicated, and one-quarter were wearing helmets. There have been an increasing number of facial fractures associated with e-scooter use following the start of the shared e-scooter trial. Zygomaticomaxillary complex fractures were the most common pattern of facial fracture seen. Most patients required surgical management of their injuries. Policymakers should consider how to improve the enforcement of current regulations, given the healthcare cost associated with the management of these preventable injuries., (Copyright © 2024 European Association for Cranio-Maxillo-Facial Surgery. All rights reserved.)

Objectives: To compare the impact attenuating capabilities between ice hockey helmets manufactured with and without XRD impact protection foam, worn with and without a XRD skullcap, at reducing sub-concussive head accelerations., Design: Quasi-experimental laboratory., Methods: Ice hockey helmets were fit onto a Hybrid III 50th Head Form Head and dropped 25 times onto the left temporal side for each condition: XRD foam helmet, XRD foam helmet with XRD skullcap adjunct, non-XRD foam helmet, and non-XRD foam helmet with XRD skullcap adjunct. The helmets were dropped from a height that resulted in sub-concussive linear accelerations (25-80 g's). Using a tri-axial accelerometer, peak linear accelerations (g) were measured, and the average was used to compare impact attenuation properties across the four conditions., Results: The highest linear accelerations were observed in the XRD foam helmet without skullcap (32.97 ± 0.61 g) and were significantly greater (p < 0.001) than the XRD helmet with skullcap (21.38 ± 0.76 g). The helmet without XRD foam elicited the lowest peak linear accelerations (16.10 ± 0.73 g) which were significantly lower than the XRD foam helmet regardless of whether the skullcap was added (p < 0.001)., Conclusions: Although sub-concussive loads are potentially just as dangerous, much of the research regarding helmet and skullcap efficacy appears to be at high concussive impacts; <70 g's. The findings suggest that helmets with incorporated XRD foam, either within the design or added as an adjunct, are less effective at attenuating linear accelerations at sub-concussive levels than the low-density foam helmet., Competing Interests: Declaration of interest statement None., (Copyright © 2024. Published by Elsevier Ltd.)

Traumatic brain injury (TBI) is a common injury in the workplace. Trips and falls are the leading causes of TBI in the workplace. However, industrial safety helmets are not designed for protecting the head under these impact conditions. Instead, they are designed to pass the regulatory standards which test head protection against falling heavy and sharp objects. This is likely to be due to the limited understanding of head impact conditions from trips and falls in workplace. In this study, we used validated human multi-body models to predict the head impact location, speed and angle (measured from the ground) during trips, forward falls and backward falls. We studied the effects of worker size, initial posture, walking speed, width and height of the tripping barrier, bracing and falling height on the head impact conditions. Overall, we performed 1692 simulations. The head impact speed was over two folds larger in falls than trips, with backward falls producing highest impact speeds. However, the trips produced impacts with smaller impact angles to the ground. Increasing the walking speed increased the head impact speed but bracing reduced it. We found that 41% of backward falls and 19% of trips/forward falls produced head impacts located outside the region of helmet coverage. Next, we grouped all the data into three sub-groups based on the head impact angle: [0°, 30°], (30°, 60°] and (60°, 90°] and excluded groups with small number of cases. We found that most trips and forward falls lead to impact angles within the (30°, 60°] and (60°, 90°] groups while all backward falls produced impact angles within (60°, 90°] group. We therefore determined five representative head impact conditions from these groups by selecting the 75th percentile speed, mean value of angle intervals and median impact location (determined by elevation and azimuth angles) of each group. This led to two representative head impact conditions for trips: 2.7 m/s at 45° and 3.9 m/s at 75°, two for forward falls: 3.8 m/s at 45° and 5.5 m/s at 75° and one for backward falls: 9.4 m/s at 75°. These impact conditions can be used to improve industrial helmet standards., (© 2023. The Author(s).)

Purpose: Wearable sensors are used to measure head impact exposure in sports. The Head Impact Telemetry (HIT) System is a helmet-mounted system that has been commonly utilized to measure head impacts in American football. Advancements in sensor technology have fueled the development of alternative sensor methods such as instrumented mouthguards. The objective of this study was to compare peak magnitude measured from high school football athletes dually instrumented with the HIT System and a mouthpiece-based sensor system., Methods: Data was collected at all contact practices and competitions over a single season of spring football. Recorded events were observed and identified on video and paired using event timestamps. Paired events were further stratified by removing mouthpiece events with peak resultant linear acceleration below 10 g and events with contact to the facemask or body of athletes., Results: A total of 133 paired events were analyzed in the results. There was a median difference (mouthpiece subtracted from HIT System) in peak resultant linear and rotational acceleration for concurrently measured events of 7.3 g and 189 rad/s 2 . Greater magnitude events resulted in larger kinematic differences between sensors and a Bland Altman analysis found a mean bias of 8.8 g and 104 rad/s 2 , respectively., Conclusion: If the mouthpiece-based sensor is considered close to truth, the results of this study are consistent with previous HIT System validation studies indicating low error on average but high scatter across individual events. Future researchers should be mindful of sensor limitations when comparing results collected using varying sensor technologies., (© 2024. The Author(s).)

Positional skull deformities have been on the rise for decades and can be treated with molding helmets in early childhood. Parents often fear later cosmetic stigmatization, but also a reduced quality of life (QoL) during treatment. The aim of this study was to examine therapy results in our patient collection from a new perspective. Cranial vault asymmetry (CVA), cranial vault asymmetry index (CVAI), and cranial index (CI) were compared before and after molding helmet therapy. Correction was defined by a decrease in CVA <3.5 mm and CI <90%. Subjective therapy outcome, side effects and QoL from the parents' perspective were determined using a questionnaire. There were 25 patients included. Differences between pretherapeutic and posttherapeutic CVA, CVAI, and CI were significant ( P <0.01). An objective correction according to the defined values was observed in only 12% of cases. However, 76% of parents stated that their child's skull shape was normal after therapy. There were 60 side effects reported in 23 cases. The QoL of 21 children was assessed as unimpaired during helmet therapy. Even though complete normalization was rarely observed, the parameters were significantly different after therapy, and subjective reduction in skull deformity was common., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of Mutaz B. Habal, MD.)

Sporting helmets contain force attenuating materials which reduce traumatic head injury risk and may influence sport-related concussion (SRC) sequelae. The purpose of this study was to examine the association of sport helmet status with SRC-clinical presentation and recovery trajectories in men's collegiate athletes. Sport helmet status was based on the nature of sports being either helmeted/non-helmeted. 1070 SRCs in helmeted (HELM) sports (Men's-Football, Ice Hockey, and Lacrosse), and 399 SRCs in non-helmeted (NOHELM) sports (Men's-Basketball, Cheerleading, Cross Country/Track & Field, Diving, Gymnastics, Soccer, Swimming, Tennis, and Volleyball) were analyzed. Multivariable negative binomial regression models analyzed associations between sport helmet status and post-injury cognition, balance, and symptom severity, adjusting for covariate effects (SRC history, loss of consciousness, anterograde/retrograde amnesia, event type). Kaplan-Meier curves evaluated median days to: initiation of return to play (iRTP) protocol, and unrestricted RTP (URTP) by sport helmet status. Log-rank tests were used to evaluate differential iRTP/URTP between groups. Two independent multivariable Weibull accelerated failure time models were used to examine differential iRTP and URTP between groups, after adjusting for aforementioned covariates and symptom severity score. Overall, the median days to iRTP and URTP was 6.3 and 12.0, respectively, and was comparable across NOHELM- and HELM-SRCs. Post-injury symptom severity was lower (Score Ratio 0.90, 95%CI 0.82, 0.98), and cognitive test performance was higher (Score Ratio 1.03, 95%CI 1.02, 1.05) in NOHELM-compared to HELM-SRCs. Estimated time spent recovering to iRTP/URTP was comparable between sport helmet status groups. Findings suggest that the grouping of sports into helmeted and non-helmeted show slight differences in clinical presentation but not recovery., (© 2024. The Author(s) under exclusive licence to Biomedical Engineering Society.)

Helmet-testing headforms replicate the human head impact response, allowing the assessment of helmet protection and injury risk. However, the industry uses three different headforms with varying inertial and friction properties making study comparisons difficult because these headforms have different inertial and friction properties that may affect their impact response. This study aimed to quantify the influence of headform coefficient of friction (COF) and inertial properties on oblique impact response. The static COF of each headform condition (EN960, Hybrid III, NOCSAE, Hybrid III with a skull cap, NOCSAE with a skull cap) was measured against the helmet lining material used in a KASK prototype helmet. Each headform condition was tested with the same helmet model at two speeds (4.8 & 7.3 m/s) and two primary orientations (y-axis and x-axis rotation) with 5 repetitions, totaling 100 tests. The influence of impact location, inertial properties, and friction on linear and rotational impact kinematics was investigated using a MANOVA, and type II sums of squares were used to determine how much variance in dependent variables friction and inertia accounted for. Our results show significant differences in impact response between headforms, with rotational head kinematics being more sensitive to differences in inertial rather than frictional properties. However, at high-speed impacts, linear head kinematics are more affected by changes in frictional properties rather than inertial properties. Helmet testing protocols should consider differences between headforms' inertial and frictional properties during interpretation. These results provide a framework for cross-comparative analysis between studies that use different headforms and headform modifiers., (© 2024. The Author(s).)

Helmets and shoulder pads are required equipment intended to protect American football athletes by attenuating collision forces during participation. Surprisingly, research differentiating kinematics from head impacts initiated by helmets from those initiated by shoulder pads among adolescent athletes has not been completed. The current study's purpose was to determine the effects of equipment on head impact kinematics. Sixty-nine male American football athletes from three high schools wore helmets equipped with Head Impact Telemetry (HIT) System instrumentation to quantify peak linear (g) and rotational (rad/s 2 ) accelerations. Data were extracted for video-confirmed impacts during two competitions. Separate multivariable linear regressions using ordinary least squares were conducted to determine if equipment type (helmet vs. shoulder pad) was associated with log-transformed linear and rotational accelerations. In total, 1150 video-confirmed impacts involved helmet (N = 960) or shoulder pad (N = 190) initiated contact. Linear (p = 0.809) and rotational (p = 0.351) acceleration were not associated with equipment type. Head impact kinematics were similar between impacts initiated by either helmets or shoulder pads and suggests an opponent's shoulder pads and helmet can deliver comparable forces to the struck player. Equipment manufacturers may need to consider the unintended role shoulder pads may contribute to head injury risk., (© 2024. The Author(s) under exclusive licence to Biomedical Engineering Society.)

Dummy headforms used for impact testing have changed little over the years, and frictional characteristics are thought not to represent the human head accurately. The frictional interface between the helmet and head is an essential factor affecting impact response. However, few studies have evaluated the coefficient of friction (COF) between the human head and helmet surface. This study's objectives were to quantify the human head's static and dynamic COF and evaluate the effect of biological sex and hair properties. Seventy-four participants slid their heads along a piece of helmet foam backed by a fixed load cell at varying normal force levels. As normal force increased, static and dynamic human head COF decreased following power-law curves. At 80 N, the static COF is 0.32 (95% CI 0.30-0.34), and the dynamic friction coefficient is 0.27 (95% CI 0.26-0.28). Biological sex and hair properties were determined not to affect human head COF. The COFs between the head and helmet surface should be used to develop more biofidelic head impact testing methods, define boundary conditions for computer simulations, and aid decision-making for helmet designs., (© 2023. The Author(s).)

Introduction: Strong neck muscles may decrease the risk of flight-induced neck pain and possible disability among fast jet pilots. The purpose of this study was to examine the intra- and interrater reliability of a commercial force gauge attached to a pilot's helmet for measuring isometric force production of the neck muscles., Methods: A total of 41 subjects performed maximal isometric cervical flexion, extension, and lateral flexion in two measurement sessions for intrarater reliability, and 31 of these subjects participated in a third session for measuring interrater reliability. Delayed muscle soreness and neck pain were assessed using the Visual Analog Scale before and after each measurement session. The intraclass correlation coefficient (ICC) was used to compare values between the test and retest assessments., Results: The overall interrater reliability was good (ICC 0.79-0.90), whereas the intrarater reliability varied from moderate to good (ICC 0.58-0.84). In both intra- and interrater reliability, the flexion test had good (ICC 0.84-0.89) reliability, while the lateral flexion test results had moderate to good (ICC 0.73-0.90) reliability. The extension test had the lowest reliability in both intra- (ICC 0.58) and interrater (ICC 0.79) tests. The average visual analog scale score (from 1-100 scale) prior to the second measurement session was 16 ± 18 in delayed muscle soreness and 0 ± 0 in neck pain., Discussion: The present study demonstrated that the helmet-attached force gauge is a reliable, safe, and clinically applicable method to evaluate isometric neck strength in the flexion and lateral flexion directions. Honkanen T, Mattila V, Kinnunen O, Janhunen M, Sovelius R, Vaara JP, Kyröläinen H. Reliability of a flight helmet-attached force gauge in measuring isometric neck muscle strength. Aerosp Med Hum Perform. 2024; 95(10):788-793.

Protective headgear effects measured in the laboratory may not always translate to the field. In this study, we evaluated the impact attenuation capabilities of a commercially available padded helmet shell cover in the laboratory and on the field. In the laboratory, we evaluated the padded helmet shell cover's efficacy in attenuating impact magnitude across six impact locations and three impact velocities when equipped to three different helmet models. In a preliminary on-field investigation, we used instrumented mouthguards to monitor head impact magnitude in collegiate linebackers during practice sessions while not wearing the padded helmet shell covers (i.e., bare helmets) for one season and whilst wearing the padded helmet shell covers for another season. The addition of the padded helmet shell cover was effective in attenuating the magnitude of angular head accelerations and two brain injury risk metrics (DAMAGE, HARM) across most laboratory impact conditions, but did not significantly attenuate linear head accelerations for all helmets. Overall, HARM values were reduced in laboratory impact tests by an average of 25% at 3.5 m/s (range: 9.7 to 39.6%), 18% at 5.5 m/s (range: - 5.5 to 40.5%), and 10% at 7.4 m/s (range: - 6.0 to 31.0%). However, on the field, no significant differences in any measure of head impact magnitude were observed between the bare helmet impacts and padded helmet impacts. Further laboratory tests were conducted to evaluate the ability of the padded helmet shell cover to maintain its performance after exposure to repeated, successive impacts and across a range of temperatures. This research provides a detailed assessment of padded helmet shell covers and supports the continuation of in vivo helmet research to validate laboratory testing results., (© 2023. The Author(s) under exclusive licence to Biomedical Engineering Society.)

Neck pain associated with helmet-wear is an occupational health problem often observed in helicopter pilots and aircrew. Whether aircrew helmet wearing is associated with physiological and biomechanical differences between sexes is currently unknown. This study investigated neuromuscular activation patterns during different helmet-wearing conditions. The helmet load was manipulated through a novel Helmet Balancing System (HBS) in healthy, non-pilot male and female participants (n = 10 each, age 19-45 years) in two phases. Phase A assessed the acute effects of helmet-wear on neck muscles activation during head movements. Phase B examined changes in muscle activity and cervical disc height after wearing a helmet for 45 min. In Phase A, muscle activity was similar between sexes in many movements, but it was higher in female participants when wearing a helmet than in males. The HBS reduced muscle activity in both sexes. In Phase B, female participants exhibited a greater level of muscular fatigue, and male participants' cervical disc height was significantly decreased [5.7 (1.4) vs. 4.4 (1.5) mm, P < 0.001] after continuous wearing. Both sexes showed no significant change in muscle fatigue and disc height [male: 5.0 (1.3) vs. 5.2 (1.4) mm, P = 0.604] after applying HBS. These findings demonstrate sex-specific physiological and biomechanical responses to wearing a helmet. They may indicate different postural and motor control strategies, associated with different neck pain aetiologies in male and female aircrew, the knowledge of which is important to reduce or prevent musculoskeletal injuries associated with helmet wearing., (© 2024 The Author(s). Experimental Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Road traffic injuries present a significant public health burden, especially in developing countries. This systematic review and meta-analysis synthesized global evidence on motorcycle helmet use prevalence by including 299 records across 249 articles involving 5,006,476 participants from 1982 to 2022. The findings revealed a declining trend in helmet use prevalence over the past four decades, with an overall prevalence of 48.71%. The meta-regression analysis did not find any statistically significant change in the overall prevalence. Subgroup analysis showed higher helmet use prevalence in observation/survey records (54.29%) compared to crashed patient records (44.84%). Riders/Motorcyclists demonstrated a higher likelihood of wearing helmets than passengers in both observation/survey records (62.61 vs. 28.23%) and crashed patient records (47.76 vs. 26.61%). Countries with mandatory helmet use laws had higher helmet usage prevalence compared to those without (52.26 vs. 37.21%). The African continent had the lowest helmet use rates, while Latin America and the Caribbean regions had higher rates. This study provides a comprehensive overview of global helmet use prevalence, emphasizing disparities between high and low-income countries, variations in law enforcement, and trends over four decades. Targeted interventions are necessary to improve helmet-wearing habits, especially among passengers and regions with low usage rates. Effective legislation and awareness campaigns are crucial for promoting helmet use and reducing road traffic injuries burden.

Introduction: In the last decade, concussions and subconcussive brain trauma in football and other high impact sports have become of increasing concern. Tackling, in youth football, accounts for a high proportion of head impacts and injuries, including concussions. Thus, minimizing head impact severity during tackling may help in reducing concussion risk and subconcussive brain trauma. However, it is unknown how discrete aspects of play in youth football relate to head impact severity during tackling., Methods: 25 youth tackle football players (12.9 ± 0.6 yr) wore helmets outfitted with the Head Impact Telemetry (HIT) System during two football seasons (64 practices and 18 games). Measures of head impact severity, including linear acceleration (LA) and rotational acceleration (RA), were collected at each session, along with videography. Videos and HIT System data were cross analyzed using a validated rubric to code each registered head impact based on several pre-identified characteristics of play. Sample distributions of play characteristics were compared using the nonparametric Mann-Whitney U test. Level of significance for all tests was α = 0.05., Results: There were 1025 head impacts identified for players making a tackle or being tackled. LA of head impacts was significantly greater (p = 0.017) for players making a tackle (n = 614; 21.70 [16.40-30.13] g) than players being tackled (n = 411; 20.50 [15.90-30.10] g). In comparing head impacts on tackles, LA was significantly greater (p = 0.010) for special teams (n = 39; 29.10 [21.40-39.70] g) over defense (n = 348; 22.50 [16.90-31.55] g), and RA was significantly greater (p = 0.003) for special teams (n = 39; 2241 [1223-3175] rad ∙ sec-1) over defense (n = 348; RA = 1618 [1004-2293] rad ∙ sec-1). While being tackled, player-to-ground head impacts LA values (n = 102; 25.85 [18.65-35.13] g) were significantly greater (p less than 0.001) than player-to-player head impacts (n = 308; 19.75 [14.95-26.68] g), and player-to-ground head impacts RA values (n = 102; 1687 [1108-2690] rad ∙ sec-1) were significantly greater (p less than 0.001) than player-to-player head impacts (n = 308; 1313 [906-1832] rad ∙ sec-1)., Conclusions: There are certain characteristics of play in youth football that were associated with higher magnitude head impacts during tackling, including being the tackler, special teams plays and head contact to the ground while being tackled. These characteristics of play may serve as targets for mitigation efforts aimed at reducing head impact severity in youth football., (Copyright© South Dakota State Medical Association.)

From a global perspective, low helmet-wearing rates in children are an ongoing concern. International studies show adult helmet-wearing rates are consistently higher than those of children. Research also shows parents are highly influential in promoting healthy behavior in their children. Parent-focused helmet-wearing campaigns are a practical way to actively feature parents influencing helmet-wearing in children. The current study obtained anonymous parent-focused survey data on parent and child helmet-wearing practices, perceived affects of helmet use on children's health, and beliefs about brain injury prevention from a sample of Vietnams parents. Findings from this study are consistent with previous international research that shows adults wear helmets at higher rates than children. Data from this study may help those responsible for child helmet safety campaigns develop more effective child helmet-wearing campaigns, particularly in Southeast Asian countries., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article

Background: Sterile surgical helmet systems are frequently utilized in total knee arthroplasty procedures to protect the surgeon while maintaining a comfortable working environment. However, common helmet systems pressurize the space between the surgical gown and the surgeon's skin. In gowns with a back seam, this may allow contaminated skin particles to escape into the surgical field. By measuring bacterial colony-forming units (CFUs), this study sought to determine if occlusion of the open back seam reduced the risk of potential contamination., Methods: First, qualitative analysis depicting airflow variations between gown configurations was performed using the Schlieren Spherical Mirror imaging system. Each gown configuration consisted of a sterile surgical helmet and one of 3 gown configurations: a standard gown with rear-tied closure, a standard gown with a surgical vest, and a zippered Toga-style gown. Next, a surgeon then performed simulated surgical activities for 60 minutes within a 1.4 m 3 isolation chamber with work surfaces and controllable filtered air exchanges. During each procedure, contaminated particles were collected on sets of agar settle plates positioned directly behind the surgeon. Upon completion, the agar plates were incubated in a biolab, and the number of bacterial and fungal CFUs was counted. The experimental procedure was repeated 12 times for each gown configuration, with sterilization of the chamber between runs. Contamination rates were expressed as CFUs/m 2 /h., Results: The mean contamination rate measured with the standard gown was 331.7 ± 52.0 CFU/m 2 /h. After the addition of a surgical vest, this rate decreased by 45% to 182.2 ± 30.8 CFU/m 2 /h (P = .02). Similarly, with the Toga-style gown, contamination rates dropped by 49% to 170.5 ± 41.9 CFU/m 2 /h (P = .01)., Conclusions: When used in conjunction with surgical helmet systems, conventional surgical gowns do not prevent potential contamination of the surgical field. We recommend that staff within the surgical field cover the back seam of standard gowns with a vest or don a zippered Toga-style gown., (Copyright © 2024 Elsevier Inc. All rights reserved.)

In 2015, the VIRTUS helmet was introduced to UK Armed Forces and will ultimately replace the Mark 7 combat helmet. The VIRTUS helmet has a reduced trimline compared to the Mark 7 helmet and can incorporate attachments such as a visor, mandible guard and nape protection. An anonymous questionnaire was provided to 200 UK Armed Forces personnel deployed to four locations on Operation TORAL in Afghanistan between September and October 2019. This is the first User feedback survey assessing the VIRTUS helmet in an operational environment. Users were measured to ascertain the fit of their helmet and asked to rate perceived helmet mass and comfort using a 5-point Likert scale. Users were also asked whether the VIRTUS helmet was better than previous helmets and about their use of the nape protection. The VIRTUS helmet was perceived to be an improvement over previously issued UK combat helmets in terms of both comfort and mass., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2024. Published by Elsevier Ltd. All rights reserved.)

Objective: Employ a novel testing method to assess Multi Directional Impact Protection System (MIPS) helmet technology on rotational velocity and acceleration during head impact., Methods: An optimization study was completed utilizing a 50th percentile male Hybrid III anthropomorphic test device (ATD). Helmets included expanded polystyrene foam (EPS) and two different MIPS helmets (MIPS 1, MIPS 2). A 24.38-m-long elevated track with rails and a motorized sled was utilized to replicate a fall from approximately 2.13 m. The sled was set to a speed of 20.92 kph, where a tripping mechanism induced rotation in the ATD from the sled and onto a sand surface. During impact of the ATD with the sand surface, head kinematics were measured using resultant acceleration (peak G's), duration of impact (ms), and rotational velocity (rad/s)., Results: A total of three trials for each helmet did not demonstrate a significant difference between the EPS vs. MIPS 1 group with, peak (G's) for resultant acceleration ( p  = 0.100), duration (ms) for resultant acceleration, ( p  = 0.100), peak (G's) for rotational velocity, ( p  = 0.700), and duration (ms) for rotational velocity ( p  = 0.700). Similarly, the EPS vs. MIPS 2 testing demonstrated no significant differences between the MIPS 2 helmet compared to the EPS helmet, with resultant acceleration ( p  = 0.400), duration acceleration ( p  = 0.200), rotational velocity ( p  = 0.400) and duration velocity ( p  = 0.400). However, when the MIPS helmet data were pooled, and the EPS helmet data were compared, a statistically significant difference in the duration of acceleration was found ( p  = 0.048)., Conclusions: Current testing uses a helmeted head form which is dropped or rolled from a prescribed height. These methods discount the loading placed on the neck and head through the angular momentum of the body. Our novel testing method did not find significant differences between the helmet types in diminishing peak rotational forces to the brain; however, our data suggests that MIPS helmet liners may reduce duration of impact. The reduction of acceleration duration could indicate less rotation of the neck, due to the dampening of these forces by the MIPS liners.

Using data from the 2022 Korea Community Health Survey (n = 13 320), this study investigated helmet use and related factors among Korean adults using personal mobility devices, without distinguishing between private and hired users. Among mobility device users, 32.1% responded that they always wore a helmet. The proportion of helmet use was 35.2% among men, 25.8% among women, 29.2% among those aged 19-44 years, 42.3% among those aged 45-64 years and 26.6% among those aged 65 years or older. Furthermore, those who drank less frequently and were physically active were more likely to wear helmets. Moreover, people who always wore a seat belt when driving a car or sitting in the rear seat and people who always wore a helmet when riding a motorcycle were more likely to wear a helmet while using electric personal mobility devices. Approximately one-third of users always wore a helmet. The helmet-wearing rate was related to general characteristics such as gender and education level, and to safety behaviors such as wearing a seat belt when driving a car, sitting in the rear seat of a car, or when riding a motorcycle. In addition to considering personal characteristics investigated in this study, the helmet-wearing rate should be improved through policies or systems at the national or regional levels., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

In the field of industrial safety, wearing helmets plays a vital role in ensuring workers' health. Aiming at addressing the complex background in the industrial environment, caused by differences in distance, the helmet small target wearing detection methods for misdetection and omission detection problems are needed. An improved YOLOv8 safety helmet wearing detection network is proposed to enhance the capture of details, improve multiscale feature processing and improve the accuracy of small target detection by introducing Dilation-wise residual attention module, atrous spatial pyramid pooling and normalized Wasserstein distance loss function. Experiments were conducted on the SHWD dataset, and the results showed that the mAP of the improved network improved to 92.0%, which exceeded that of the traditional target detection network in terms of accuracy, recall, and other key metrics. These findings further improved the detection of helmet wearing in complex environments and greatly enhanced the accuracy of detection., (© 2024. The Author(s).)

Purpose: The current study aimed to assess the protective performance of helmets equipped with multi-directional impact protection system (MIPS) under various oblique impact loads., Methods: Initially, a finite element model of a bicycle helmet with MIPS was developed based on the scanned geometric parameters of an actual bicycle helmet. Subsequently, the validity of model was confirmed using the KASK WG11 oblique impact test method. Three different impact angles (30°, 45°, and 60°) and 2 varying impact speeds (5 m/s and 8 m/s) were employed in oblique tests to evaluate protective performance of MIPS in helmets, focusing on injury assessment parameters such as peak linear acceleration (PLA) and peak angular acceleration (PAA) of the head., Results: The results demonstrated that in all impact simulations, both assessment parameters were lower during impact for helmets equipped with MIPS compared to those without. The PAA was consistently lower in the MIPS helmet group, whereas the difference in PLA was not significant in the no-MIPS helmet group. For instance, at an impact velocity of 8 m/s and a 30° inclined anvil, the MIPS helmet group exhibited a PAA of 3225 rad/s 2 and a PLA of 281 g. In contrast, the no-MIPS helmet group displayed a PAA of 8243 rad/s 2 and a PLA of 292 g. Generally, both PAA and PLA parameters decreased with the increase of anvil angles. At a 60° anvil angles, PAA and PLA values were 664 rad/s 2 and 20.7 g, respectively, reaching their minimum., Conclusion: The findings indicated that helmets incorporating MIPS offer enhanced protection against various oblique impact loads. When assessing helmets for oblique impacts, the utilization of larger angle anvils and rear impacts might not adequately evaluate protective performance during an impact event. These findings will guide advancements in helmet design and the refinement of oblique impact test protocols., (Copyright © 2024 Chinese Medical Association. Production and hosting by Elsevier B.V. All rights reserved.)

Purpose: To provide additional information on optimal start times and therapeutic effectiveness based on treatment outcome of Japanese infants with positional plagio- and brachycephaly (PPB) receiving cranial molding helmet therapy (CMHT)., Methods: In this retrospective cohort study, data from a 3D head scanning system was analyzed from 2173 Japanese infants who completed CMHT. Anterior and posterior symmetry ratio (ASR and PSR) and longitudinal to transverse diagonal ratios (LD/TDR) were calculated based on skull shape at helmet design and at completion of therapy. The outcomes were evaluated using the regression analysis and a predictive model using cranial parameters was developed., Results: The earlier the start of therapy, the greater the therapeutic effect on ASR, PSR, and LD/TDR (ASR, -0.134 percent points (ppt)/day; PSR, -0.086 ppt/day; and LD/TDR, -0.131 ppt/day). In the predictive model, in addition to starting age of the therapy, sex (male), the degree of deformity of the head (DoD) (moderate and severe), quadrant volume, PSR, and head circumference at the start of treatment also had a positive effect on changes in ASR, DoD (moderate and severe), ASR, LD/TDR and transverse diameter for PSR, sex (male), DoD (moderate), quadrant volume, PSR, and head circumference for LD/TDR., Conclusion: The starting age of therapy had a relatively smaller contribution to outcome effects. Applying the cranial parameter obtained at the start of treatment to the predictive model helps to predict the effect of CMHT and whether PPB can be treated with CMHT in infants of older age., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Endoscopic strip craniectomy followed by helmet therapy (ESCH) is a minimally invasive approach for correcting sagittal craniosynostosis. The treatment involves a patient-specific helmet designed to facilitate lateral growth while constraining sagittal expansion. In this study, finite element modelling was used to predict post-treatment head reshaping, improving our comprehension of the necessary helmet therapy duration., Method: Six patients (aged 11 weeks to 9 months) who underwent ESCH at Connecticut Children's Hospital were enrolled in this study. Day-1 post-operative 3D scans were used to create skin, skull, and intracranial volume models. Patient-specific helmet models, incorporating areas for growth, were designed based on post-operative imaging. Brain growth was simulated through thermal expansion, and treatments were modelled according to post-operative Imaging available. Mechanical testing and finite element modelling were combined to determine patient-specific mechanical properties from bone samples collected from surgery. Validation compared simulated end-of-treatment skin surfaces with optical scans in terms of shape matching and cranial index estimation., Results: Comparison between the simulated post-treatment head shape and optical scans showed that on average 97.3 ± 2.1 % of surface data points were within a distance range of -3 to 3 mm. The cranial index was also accurately predicted (r = 0.91)., Conclusions: In conclusion, finite element models effectively predicted the ESCH cranial remodeling outcomes up to 8 months postoperatively. This computational tool offers valuable insights to guide and refine helmet treatment duration. This study also incorporated patient-specific material properties, enhancing the accuracy of the modeling approach., Competing Interests: Declaration of competing interest None to declare., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Context: Guardian Caps (GCs) are currently the most popular external helmet add-on designed to reduce the magnitude of head impacts experienced by American football players. Guardian Caps have been endorsed by influential professional organizations; however, few studies evaluating their efficiency are publicly available., Objective: To present preliminary on-field head kinematics data for National Collegiate Athletic Association (NCAA) Division I American football players using instrumented mouthguards through closely matched preseason workouts with and without GCs., Design: Case series., Setting: The 2022 American football preseason., Patients or Other Participants: Twenty-five male NCAA Division I student-athletes participating in American football completed some portion of the 6 workouts included in this study. Of the 25 participants, 7 completed all 6 workouts using their instrumented mouthguards., Main Outcome Measure(s): Peak linear acceleration (PLA), peak angular acceleration (PAA), and total impacts were collected via instrumented mouthguards during 3 preseason workouts using traditional helmets (TRAD condition) and 3 using a TRAD and GCs (GC condition). The TRAD and GC values for PLA, PAA, and total impacts were evaluated using analyses of variance., Results: No difference was present between the collapsed mean values for the entire sample between the TRAD and GC conditions for PLA (TRAD = 16.3g ± 2.0g, GC = 17.2g ± 3.3g, P = .20), PAA (TRAD = 992.1 ± 209.2 rad/s2, GC = 1029.4 ± 261.1 rad/s2, P = .51), or the total number of impacts (TRAD = 9.3 ± 4.7, GC = 9.7 ± 5.7, P = .72). Similarly, no difference was observed between the TRAD and GC conditions for PLA (TRAD = 16.1g ± 1.2g, GC = 17.2g ± 2.79g, P = .32), PAA (TRAD = 951.2 ± 95.4 rad/s2, GC = 1038.0 ± 166.8 rad/s2, P = .29), or total impacts (TRAD = 9.6 ± 4.2, GC = 9.7 ± 5.04, P = .32) between sessions for the 7 players who completed all 6 workouts., Conclusions: These data suggested no difference in head kinematics data (PLA, PAA, and total impacts) when GCs were worn. Therefore, GCs may not be effective in reducing the magnitude of head impacts experienced by NCAA Division I American football players., (© by the National Athletic Trainers' Association, Inc.)

Objective: Deformational Plagiocephaly (DP) is commonly treated with cranial orthosis, or helmet therapy. A large, national study on the impact of insurance status on helmet outcomes is lacking. We assessed treatment outcomes for helmet therapy based on insurance status., Design: This was a retrospective data analysis of patients referred to Cranial Technologies, Inc for helmet therapy between 2014-2020 across 21 states., Patients, Participants: There were a total of 211,417 patients referred for helmeting, of whom 141,513 received helmet therapy., Main Outcomes Measures: Multivariate regression was used to assess the relationship of insurance status with post-treatment residual flattening, measured by cephalic index (CI) and cranial vault asymmetry index (CVAI), and treating provider rating of success., Results: Patients with Medicaid were more likely to complete treatment with residual flattening measured by CI and CVAI when compared to patients with private insurance (OR: 1.58, CI: 1.51-1.65, p < 0.001 and OR: 1.21, CI: 1.15-1.28, p < 0.001, respectively). Providers of patients with Medicaid were more likely to give a low rating of success following treatment (OR: 3.25, CI: 2.70-3.92, p < 0.001)., Conclusions: Our study investigating the impact of insurance status on helmet therapy across 21 states found that patients with Medicaid were more likely to experience residual flattening and have lower provider-rated outcomes compared to those with commercial insurance. Given significant caregiver burden posed by helmet therapy, which requires frequent visits and consistent helmet use, caregivers of patients with Medicaid may require greater support to reduce outcome disparities observed here., Competing Interests: Declaration of Conflicting InterestsMr. Littlefield is the Chief Science and Technology Officer at Cranial Technologies, Inc., and he has a financial interest in Cranial Technologies, Inc. All other authors have no conflicts of interest relevant to this article to disclose.

Headguard use is appropriate during some combat sports activities where the risks of injury to the face and ears are elevated. Headguards are highly effective in reducing the incidence of facial lacerations in studies of amateur boxers and are just as effective in other striking sports. They should be used in scenarios - especially sparring prior to competitions - where avoidance of laceration and subsequent exposure to potential blood-borne pathogens is important. Headguards are appropriate where avoidance of auricular injury is deemed important; limited data show a marked reduction in incidence of auricular injury in wrestlers wearing headguards.Headguards should not be relied upon to reduce the risk of concussion or other traumatic brain injury. They have not been shown to prevent these types of injuries in combat sports or other sports, and human studies on the effect of headguards on concussive injury are lacking. While biomechanical studies suggest they reduce linear and rotational acceleration of the cranium, changes in athlete behavior to more risk-taking when wearing headguards may offset any risk reduction. In the absence of high-quality studies on headguard use, the Association of Ringside Physicians recommends that further research be conducted to clarify the role of headguards in all combat sports, at all ages of participation. Furthermore, in the absence of data on gender differences, policies should be standardized for men and women.

Wearing helmets is essential in two-wheeler traffic to reduce the incidence of injuries caused by accidents. We present FB-YOLOv7, an improved detection network based on the YOLOv7-tiny model. The objective of this network is to tackle the problems of both missed detection and false detection that result from the difficulties in identifying small targets and the constraints in equipment performance during helmet detection. By applying an enhanced Bi-Level Routing Attention, the network can improve its capacity to extract global characteristics and reduce information distortion. Furthermore, we deploy the AFPN framework and effectively resolve information conflict using asymptotic adaptive feature fusion technology. Incorporating the EfficiCIoU loss significantly improves the prediction box's accuracy. Experimental trials done on specific datasets reveal that FB-YOLOv7 attains an accuracy of 87.2% and 94.6% on the mean average precision (mAP@.5). Additionally, it maintains a high level of efficiency with frame rates of 129 and 126 frames per second (FPS). FB-YOLOv7 surpasses the other six widely-used detection networks in terms of detection accuracy, network implementation requirements, sensitivity in detecting small targets, and potential for practical applications., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Huang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Concussions, a prevalent public health concern in the United States, often result from mild traumatic brain injuries (mTBI), notably in sports such as American football. There is limited exploration of smart-textile-based sensors for measuring the head impacts associated with concussions in sports and recreational activities. In this paper, we describe the development and construction of a smart textile impact sensor (STIS) and validate STIS functionality under high magnitude impacts. This STIS can be inserted into helmet cushioning to determine head impact force. The designed 2 × 2 STIS matrix is composed of a number of material layered structures, with a sensing surface made of semiconducting polymer composite (SPC). The SPC dimension was modified in the design iteration to increase sensor range, responsiveness, and linearity. This was to be applicable in high impact situations. A microcontroller board with a biasing circuit was used to interface the STIS and read the sensor's response. A pendulum test setup was constructed to evaluate various STISs with impact forces. A camera and Tracker software were used to monitor the pendulum swing. The impact forces were calculated by measuring the pendulum bob's velocity and acceleration. The performance of the various STISs was measured in terms of voltage due to impact force, with forces varying from 180 to 722 N. Through data analysis, the threshold impact forces in the linear range were determined. Through an analysis of linear regression, the sensors' sensitivity was assessed. Also, a simplified model was developed to measure the force distribution in the 2 × 2 STIS areas from the measured voltages. The results showed that improving the SPC thickness could obtain improved sensor behavior. However, for impacts that exceeded the threshold, the suggested sensor did not respond by reflecting the actual impact forces, but it gave helpful information about the impact distribution on the sensor regardless of the accurate expected linear response. Results showed that the proposed STIS performs satisfactorily within a range and has the potential to be used in the development of an e-helmet with a large STIS matrix that could cover the whole head within the e-helmet. This work also encourages future research, especially on the structure of the sensor that could withstand impacts which in turn could improve the overall range and performance and would accurately measure the impact in concussion-causing impact ranges.

Context: A sport-related concussion (SRC) is a traumatic brain injury that is caused by biomechanical stresses and results in a complex pathophysiological process in the brain. Some in the sporting community believe that headgear (HG) can prevent SRC, and several professional Australian sports organizations, including rugby, football, and soccer clubs, recommend its use., Objective: The purpose of this study is to determine whether HG is effective in lowering the prevalence of SRC in sports., Data Sources: A systematic search for related studies published between 1985 and 2023 was conducted using the following databases: Cochrane Library, AMED, PubMed, Web of Science, and Physiotherapy Evidence Database (PEDro)., Study Selection: Only randomized controlled trials (RCTs) that investigated the effectiveness of HG in reducing SRC rate were included., Study Design: Systematic review and meta-analysis of RCTs., Level of Evidence: Level 1a., Data Extraction: Two researchers independently completed the title and abstract search and performed full-text reviews. A third reviewer was consulted to reach a consensus if any discrepancies were noted. The PEDro scale was used to evaluate the quality of the included RCTs. Data recorded from each study included authors, year of publication, type and number of players, study design, duration of the study, injury rate, compliance (%), sports/level, and exposure hours., Results: The pooled results of 6311 players and 173,383 exposure hours showed 0% SRC reduction per 1000 hours of exposure in the experimental group compared with the control group, with an injury risk ratio of 1.03 (95% CI, 0.82-1.30; P = 0.79)., Conclusion: This systematic review and meta-analysis demonstrates that HG does not prevent SRC among soccer and rugby players, and therefore the findings from this meta-analysis do not currently support the use of HG to prevent SRC in soccer or rugby., Competing Interests: The authors report no potential conflicts of interest in the development and publication of this article.

Introduction: Craniosynostosis results from premature fusion of the cranial sutures. There has been a continuous evolution of surgical correction techniques from an extensive open procedure to the minimally invasive technique., Aims and Objectives: This novel surgical technique has never been previously done in the UAE and this article documents the experience of the first team to endoscopically correct craniosynostosis with planning, surgical techniques, and customized helmet therapy., Methods: A retrospective case series of 16 nonsyndromic craniosynostosis patients with unicoronal (6), sagittal (5), bicoronal (1), frontosphenoidal (2), and metopic craniosynostoses (2) was corrected endoscopically and followed up with customized cranial helmet. Preoperative and postoperative photography, along with anthropometric measurements were taken., Results: The mean age of all patients at the time of surgery was 101 (90-117) days, mean duration of surgery was 70 minutes (38-129), mean blood loss was 120 mL (100-150), and mean duration of hospital stay 4 days (4-5). No complications and mortality were reported. Mean number of helmets was 2 (1-3). Cranial index improved in all patients with sagittal and bicoronal craniosynostosis. Close cooperation with the orthotist ensured timely helmet therapy and accurate laser scanning documentation in head molding., Conclusions: This case series has demonstrated that endoscopically craniosynostosis correction is safe, effective, and reliable and is the first reported series from the Middle East. The authors believe that every patient with nonsyndromic single‑suture craniosynostosis should be offered endoscopic correction before the age of 6 months. The orthotist forms an important part of the Multi-disciplinary team, enabling successful outcomes., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

Introduction: Endoscopic strip craniectomy (ESC) is a minimally invasive option for early surgical treatment of metopic (MC) and sagittal craniosynostosis (SC). For ESC, however, the postoperative duration and compliance of helmet therapy are crucial to correct MC and SC asymmetry. The purpose of this study is to assess the period of postoperative band therapy and determine differences, if any, between MC and SC., Methods: A single-institution retrospective review was performed for patients with MC and SC who underwent ESC from November 2015 to 2019. Patients received preoperative, postoperative, and post-band 3-dimensional imaging. Factors recorded included patient sex, insurance type, number of helmets needed, age at surgery, time of first helmet, and at time of completion of helmet therapy, cephalic index, interfrontal angle, and cranial vault asymmetry index., Results: Patients with SC and MC had ESC surgery at 3.3 and 3.4 months of age, respectively.Patients with SC were found to have completed banding therapy at a younger age (7.88 versus 10.0 mo), with shorter duration (4.17 versus 6.00 mo), and less number of bands (1.54 versus 2.21) than patients with MC. After regression analysis, suture type was found to be a significant predictor of total time in band therapy ( P =0.039) with MC requiring a longer duration of banding therapy when compared with SC., Conclusions: Suture type directly correlates with duration of helmeting therapy for patients, with patients with MC requiring longer periods of postop helmeting and increased number of bands as compared with SC., Competing Interests: T.L. is the chief scientific officer of Cranial Technologies, although did not receive any compensation for this project. Cranial Technologies provided postoperative helmeting and anthropometric raw data. The remaining authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

Very-low field (VLF) magnetic resonance imaging (MRI) offers advantages in term of size, weight, cost, and the absence of robust shielding requirements. However, it encounters challenges in maintaining a high signal-to-noise ratio (SNR) due to low magnetic fields (below 100 mT). Developing a close-fitting radio frequency (RF) receive coil is crucial to improve the SNR. In this study, we devised and optimized a helmet-shaped dual-channel RF receive coil tailored for brain imaging at a magnetic field strength of 54 mT (2.32 MHz). The methodology integrates the inverse boundary element method (IBEM) to formulate initial coil structures and wiring patterns, followed by optimization through introducing regularization terms. This approach frames the design process as an inverse problem, ensuring a close fit to the head contour. Combining theoretical optimization with physical measurements of the coil's AC resistance, we identified the optimal loop count for both axial and radial coils as nine and eight loops, respectively. The effectiveness of the designed dual-channel coil was verified through the imaging of a CuSO4 phantom and a healthy volunteer's brain. Notably, the in-vivo images exhibited an approximate 16-25 % increase in SNR with poorer B 1 homogeneity compared to those obtained using single-channel coils. The high-quality images achieved by T1, T2-weighted, and fluid-attenuated inversion-recovery (FLAIR) protocols enhance the diagnostic potential of VLF MRI, particularly in cases of cerebral stroke and trauma patients. This study underscores the adaptability of the design methodology for the customization of RF coil structures in alignment with individual imaging requirements., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Measurements of brain deformations under injurious loading scenarios are actively sought. In this work, we report experimentally measured head kinematics and corresponding dynamic, two-dimensional brain simulant deformations in head surrogates under a blunt impact, with and without a helmet. Head surrogates used in this work consisted of skin, skull, dura, falx, tentorium, and brain stimulants. The head surrogate geometry was based on the global human body models consortium's head model. A base head surrogate consisting of skin-skull-brain was considered. In addition, the response of two other head surrogates, skin-skull-dura-brain, and skin-skull-dura-brain-falx-tentorium, was investigated. Head surrogate response was studied for sagittal and coronal plane rotations for impactor velocities of 1 and 3 m/s. Response of head surrogates was compared against strain measurements in PMHS. The strain pattern in the brain simulant was heterogenous, and peak strains were established within ∼30 ms. The choice of head surrogate affect the spatiotemporal evolution of strain. For no helmet case, peak MPS of ∼50-60% and peak MSS of ∼35-50% were seen in brain simulant corresponding to peak rotational accelerations of ∼5000-7000 rad/s2. Peak head kinematics and peak MPS have been reduced by up to 75% and 45%, respectively, with the conventional helmet and by up to 90% and 85%, respectively, with the helmet with antirotational pads. Overall, these results provide important, new data on brain simulant strains under a variety of loading scenarios-with and without the helmets., (Copyright © 2024 by ASME.)

Competing Interests: None declared.

The anatomy of children's heads is unique and distinct from adults, with smaller and softer skulls and unfused fontanels and sutures. Despite this, most current helmet testing standards for children use the same peak linear acceleration threshold as for adults. It is unclear whether this is reasonable and otherwise what thresholds should be. To answer these questions, helmet-protected head responses for different ages are needed which is however lacking today. In this study, we apply continuously scalable PIPER child head models of 1.5, 3, and 6 years old (YO), and an upgraded 18YO to study child helmet protection under extensive linear and oblique impacts. The results of this study reveal an age-dependence trend in both global kinematics and tissue response, with younger children experiencing higher levels of acceleration and velocity, as well as increased skull stress and brain strain. These findings indicate the need for better protection for younger children, suggesting that youth helmets should have a lower linear kinematic threshold, with a preliminary value of 150g for 1.5-year-old helmets. However, the results also show a different trend in rotational kinematics, indicating that the threshold of rotational velocity for a 1.5YO is similar to that for adults. The results also support the current use of small-sized adult headforms for testing child helmets before new child headforms are available., Competing Interests: The author PH is co-inventor of the helmet technology Mips. The authors AvS, MF and PH are all employees at Mips AB. Author XL received contracted private funds from Mips AB that supported the work This does not alter our adherence to PLOS ONE policies on sharing data and materials., (Copyright: © 2024 Li et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)