Characteristics and clinical outcomes of head-injured cyclists with and without helmets in urban and rural areas of Taiwan: A 15-year study

Effect of helmet use on maxillofacial injuries due to bicycle and scooter accidents: a systematic literature review and meta-analysis

Maxillofacial injury is a common injury resulting from bicycle (including e-bike) and scooter accidents. With 80,000 admissions to emergency departments in 2019, bicycle accidents account for more than half of all traffic-related emergency department visits in the Netherlands. The United States reports approximately 130,000 injuries and 1000 fatalities related to cycling annually. This systematic review and meta-analysis was performed to examine the protective effect of helmets against maxillofacial injuries resulting from bicycle and scooter (including e-bike and e-scooter) accidents. After a systematic literature search, 14 studies were found to be eligible for this systematic review. Of these, 11 were included in the meta-analysis. None of the included studies focused on vehicles with motors (e-bikes and e-scooters); all focused only on non-motorized vehicles. All included studies were non-randomized, which could have led to bias in the pooled results. Data from the included studies were tested for heterogeneity using the binary random-effects model (DerSimonian-Laird method), and the odds ratio for the occurrence of maxillofacial injury in cyclists wearing a helmet versus those not wearing a helmet was calculated by random-effects meta-analysis. Patients who had worn a helmet suffered significantly fewer maxillofacial injuries than patients who had not, in bicycle accidents (odds ratio 0.682). In conclusion, wearing a helmet has a significant protective effect against maxillofacial injury, indicating the need for strict helmet legislation.

Cycling area can be a confounder and effect modifier of the association between helmet use and cyclists' risk of death after a crash

The effect of helmet use on reducing the risk of death in cyclists appears to be distorted by some variables (potential confounders, effect modifiers, or both). Our aim was to provide evidence for or against the hypothesis that cycling area may act as a confounder and effect modifier of the association between helmet use and risk of death of cyclists involved in road crashes. Data were analysed for 24,605 cyclists involved in road crashes in Spain. A multiple imputation procedure was used to mitigate the effect of missing values. We used multilevel Poisson regression with province as the group level to estimate the crude association between helmet use and risk of death, and also three adjusted analyses: (1) for cycling area only, (2) for the remaining variables which may act as confounders, and (3) for all variables. Incidence–density ratios (IDR) and their 95% confidence intervals were calculated. Crude IDR was 1.10, but stratifying by cycling area disclosed a protective, differential effect of helmet use: IDR = 0.67 in urban areas, IDR = 0.34 on open roads. Adjusting for all variables except cycling area yielded similar results in both strata, albeit with a smaller difference between them. Adjusting for cycling area only yielded a strong association (IDR = 0.42), which was slightly lower in the adjusted analysis for all variables (IDR = 0.45). Cycling area can act as a confounder and also appears to act as an effect modifier (albeit to a lesser extent) of the risk of cyclists’ death after a crash.

The relationship between geographic location and outcomes following injury: A scoping review

INTRODUCTION

Globally, injury incidence and injury-fatality rates are higher in regional and remote areas. Recovery following serious injury is complex and requires a multi-disciplinary approach to management and community re-integration to optimise outcomes. A significant knowledge gap exists in understanding the regional variations in hospital and post-discharge outcomes following serious injury. The aim of this study was to review the evidence exploring the association between the geographic location, including both location of the event and place of residence, and outcomes following injury.

MATERIALS AND METHODS

A scoping review was used to investigate this topic and provide insight into geographic variation in outcomes following traumatic injury. Seven electronic databases and reference lists of relevant articles were searched from inception to October 2018. Studies were included if they measured injury-related mortality, outcomes associated with hospital admission, post-injury physical or psychological function and analysed these outcomes in relation to geographic location.

RESULTS

Of the 2,213 studies identified, 47 studies were included revealing three key groups of outcomes: mortality (n = 35), other in-hospital outcomes (n = 8); and recovery-focused outcomes (n = 12). A variety of measures were used to classify rurality across studies with inconsistent definitions of rurality/remoteness. Of the studies reporting injury-related mortality, findings suggest that there is a greater risk of fatality in rural areas overall and in the pre-hospital phase. For those patients that survived to hospital, the majority of studies included identified no difference in mortality between rural and urban patient groups. In the small number of studies that reported other in-hospital and recovery outcomes no consistent trends were identified.

CONCLUSION

Rural patients had a higher overall and pre-hospital mortality following injury. However, once admitted to hospital, there was no significant difference in mortality. Inconsistencies were noted across measures of rurality measures highlighting the need for more specific and consistent international classification methods. Given the paucity of data on the impact of geography on non-mortality outcomes, there is a clear need to develop a larger evidence base on regional variation in recovery following injury to inform the optimisation of post-discharge care services.

Impact of wearing a helmet on the risk of hospitalization and intracranial haemorrhage after a sports injury

BACKGROUND

Despite their reported protective effect against the occurrence of head injuries, helmets are still used inconsistently in sports in which they are optional. We aimed to assess the impact of helmet use on the risk of hospitalization and intracranial haemorrhage for trauma occurring during sport activities.

METHODS

Retrospective cohort of all patients who presented themselves, over an 18-month period, at the emergency department of a tertiary trauma centre for an injury sustained in a sport or leisure activity where the use of a helmet is optional. Impact of helmet use was assessed using multivariable regression analyses (relative risks, RR).

RESULTS

Among the 1,022 patients included in the study, half were cyclists and 40% were skiers or snowboarders. A total of 40 % of patients wore a helmet at the time of injury, 18% had a head injury, 16% were hospitalized and 13% of patients with a head injury had an intracranial haemorrhage. Among all patients, no association was observed between hospital admission and helmet use. However, helmet use in patients with a head injury was associated with significant reductions in the risks of hospitalization (RR 0.41 [95% CI: 0.22-0.76]) and intracranial haemorrhage (RR 0.28 [95% CI: 0.11-0.71]).

CONCLUSIONS

Results suggest that, in recreational athletes who sustain a head injury, helmet use is associated with a reduced risk of hospitalization (all sports) and intracranial haemorrhage (cyclists).

Bicycle helmets - To wear or not to wear? A meta-analyses of the effects of bicycle helmets on injuries

A meta-analysis has been conducted of the effects of bicycle helmets on serious head injury and other injuries among crash involved cyclists. 179 effect estimates from 55 studies from 1989-2017 are included in the meta-analysis. The use of bicycle helmets was found to reduce head injury by 48%, serious head injury by 60%, traumatic brain injury by 53%, face injury by 23%, and the total number of killed or seriously injured cyclists by 34%. Bicycle helmets were not found to have any statistically significant effect on cervical spine injury. There is no indication that the results from bicycle helmet studies are affected by a lack of control for confounding variables, time trend bias or publication bias. The results do not indicate that bicycle helmet effects are different between adult cyclists and children. Bicycle helmet effects may be somewhat larger when bicycle helmet wearing is mandatory than otherwise; however, helmet wearing rates were not found to be related to bicycle helmet effectiveness. It is also likely that bicycle helmets have larger effects among drunk cyclists than among sober cyclists, and larger effects in single bicycle crashes than in collisions with motor vehicles. In summary, the results suggest that wearing a helmet while cycling is highly recommendable, especially in situations with an increased risk of single bicycle crashes, such as on slippery or icy roads.

Independent factors associated with bicycle helmet use in a Korean population: A cross-sectional study

OBJECTIVE

Although identification of factors that influence helmet use during bicycle riding is necessary for the selection of groups that require safe cycling education, limited baseline data are available. The aim of the present study was to analyze the rate of helmet use and the demographic factors that were independently associated with helmet use among Korean bicycle riders.

METHODS

In this cross-sectional study, we used public data from the Sixth Korean National Health and Nutrition Examination Survey conducted in 2013 and 2014. Helmet users were defined as subjects who always, usually, or frequently wore helmets when cycling. Independent factors associated with helmet use were determined using odds ratios (ORss) adjusted for 5 demographic factors via multivariate logistic regression analysis.

RESULTS

In the total population, 4,103 individuals were bicycle riders; among these, 782 individuals (19.1%) wore helmets. A total of 21.1% of male riders used helmets, compared to 15.5% of female riders (P <.001). The adjusted logistic regression model revealed that female sex (OR = 0.665; 95% confidence interval [CI], 0.554-0.797), teenage status (OR = 0.475, 95% CI, 0.333-0.678), and low household income (OR = 0.657, 95% CI 0.513-0.841) were significantly associated with nonuse of helmets.

CONCLUSIONS

Female sex, teenage status, and low household income were independent factors associated with the nonuse of helmets. We identified factors associated with helmet use during bicycle riding through analysis of baseline data on helmet usage.

Bicycle helmets are protective against facial injuries, including facial fractures: a meta-analysis

Cycling is a popular activity. However there are risks associated with cycling, including facial injury. Helmets are often worn to prevent head injury. Evidence for their protection against facial injury is limited. This meta-analysis investigated the effect of bicycle helmets on the incidence of facial injury. The PubMed/MEDLINE, Google Scholar, and Cochrane Library databases were searched. Studies included were observational and involved adult participants. Paediatric studies, studies on helmet legislation, and those combining facial injuries with other injury types were excluded. The studies were evaluated by two reviewers. Risk of bias was assessed using the RevMan bias assessment tool. Odds ratios (OR) were extracted for facial injuries and facial fractures. Two meta-analyses were performed using these categories. Nine of the 102 studies identified were included. Helmets were protective against facial injury (OR 0.69, 95% confidence interval 0.63-0.75, P<0.0001). Five studies reported facial fracture rates; helmets were protective against these also (OR 0.79 95% confidence interval 0.70-0.90, P=0.0003). There are no randomized controlled trials on this topic and the number of studies available is small. Bicycle helmets offer protection against facial injuries and this should be considered by cyclists when deciding whether or not to use one.