Characteristics and influencing factors of head and neck injuries in motorcycle accidents: a retrospective analysis in Bangkok, Thailand
Article information
Abstract
Background
Road traffic incidents, particularly those involving motorcycles, pose a significant public health concern, especially in low-income countries. This study aims to investigate the incidence and patterns of head and neck injuries, as well as to analyze factors contributing to these injuries.
Methods
A retrospective analysis was undertaken utilizing the medical records of motorcycle incident patients derived from the provincial injury surveillance data collected between January 1, 2021, and December 31, 2021, at a single center. The study encompasses data on age, sex, rider classification, types and quantities of alcohol ingested, helmet employment, Glasgow Coma Score, Injury Severity Score, and classifications of head and neck injuries. The incidence rate of head and neck injuries correlated with motorcycle incidents will be delineated. Subsequently, a logistic regression analysis was conducted to discern the factors associated with head injury severity.
Results
The study examined motorcycle incident trauma in 1,413 patients. The incidence of head and neck injuries was 20%. Multivariable logistic regression analysis identified the age of more than 60 years, non-helmeted riding, and alcohol consumption as significant factors for head injuries, with odds ratios of 1.86, 1.76, and 4.17, respectively.
Conclusion
This study emphasizes the protective role of helmets in reducing head injuries and highlights potential associations between alcohol consumption and the severity of head injuries. These findings may be utilized to advocate for improvements in road safety policies and reduce healthcare costs related to motorcycle accidents.
INTRODUCTION
According to the 2021 statistics on road incidents in Thailand, 13,617 individuals died and 883,289 people sustained injuries in vehicle-related incidents, resulting in a considerable financial and administrative burden. Motorcycle incidents accounted for a substantial proportion of these incidents. This is illustrated particularly by Bangkok, which reported alarming overall figures: 819 fatalities and 96,536 injuries in a year, of which motorcycle incidents accounted for a striking 89.96% of the total incidents. Each year, more than 100,000 individuals are injured in motorcycle incidents requiring medical treatment, with 6% of them subsequently experiencing disabilities. Furthermore, half of all severe injuries resulting from these incidents manifest as head injuries [1].
Extensive past research underscores the critical importance of motorcycle helmets in reducing the risk and severity of head injuries. Notably, properly worn helmets can reduce the risk of death by approximately 42%. They also lower medical expenses and shorten hospitalization periods. Conversely, not wearing a helmet increases injury and death rates by an alarming factor of 3.1 [2-5]. A securely fastened helmet is highly effective in preventing specific types of head injuries. Despite the evident importance of this issue, the knowledge gap lies in understanding the distinct patterns of head and neck injuries in motorcycle incidents, particularly in the context of helmet usage. Addressing this may help reduce the burden on healthcare systems and improve public health outcomes. This study aims to report the incidence and characteristics of head and neck injuries among motorcycle accident patients.
METHODS
Data collection
The institutional review board approved this study (LH651028). This retrospective study utilized electronic patient records from the provincial injury surveillance data collected at our institution, covering the period from January 1, 2021, to December 31, 2021. The inclusion criteria encompassed all patients involved in motorcycle incidents whose records were complete and available within the study period. Patients with head and neck injuries were identified using the International Classification of Disease, 10th Edition (ICD-10) codes S00-S19.
The data collected from the electronic patient records included the following variables: (1) age: Participants’ ages were categorized into < 20, 21–40, 41–60, and > 60 years. Also divide to < 60 and > 60 year for regression analysis; (2) sex; (3) alcohol consumption at the time of the incident (yes or no); (4) helmet usage at the time of the incidents (yes or no); (5) rider type: classified as either riders (operators of the motorcycle) or pillion passengers (passengers riding on the back of the motorcycle); (6) Glasgow Coma Score: categorized as < 8, 9–12, and 13–15; and (7) Injury Severity Score: categorized as 1–8, 9–15, 16–24, and > 24.
Injury classification and fracture assessment
Injuries were classified according to ICD-10 codes as follows: S00 for superficial injuries of the head, S01 for open wounds of the head, S02 for fractures of the skull and facial bones, S03–S09 for other head injuries, and S10–S19 for neck injuries.
A plastic surgeon reviewed plain film and/or computed tomography scans in the group of fractures of the skull and facial bones (S02) to identify and categorize the fracture pattern. Fractures were categorized as single or multiple site fractures, with detailed descriptions provided.
Statistical analysis
Descriptive statistics were used to summarize the data. Continuous variables were presented as means and standard deviations, while categorical variables were expressed as frequencies and percentages. Group comparisons for continuous data were conducted using the independent t-test. For categorical variables, group differences were assessed using Fisher exact test, which was preferred over the chi-square test due to the small sample size and expected frequencies below five in some categories. To identify factors associated with head injury status, binary logistic regression analysis was performed. Variables with a p-value < 0.20 in the bivariate analysis were included in the multivariable logistic regression model. A backward selection approach was employed to refine the model, systematically removing non-significant variables. The variance inflation factor was used to assess multicollinearity among independent variables, with a threshold of variance inflation factor < 5 indicating no significant correlation. Statistical significance was defined as a p-value < 0.05.
RESULTS
One thousand four hundred and thirteen patients were included in the study. The mean age was 33 years, with a majority (66%) falling within the 21–40 age range. One thousand and two patients were male (71%). Most of the patients were riders (88%). Alcohol consumption was found in 171 patients (12%). Eight hundred and twenty-six patients (59%) were confirmed to have used a helmet. Nearly all patients had favorable Glasgow Coma Scores (99.6% with scores of 13–15), indicating alertness. Injury severity scores were primarily low (99% with scores of 1–8). Details of the patient’s demographic data are shown in Table 1.
Patient demographic data (n=1,413)
Helmet usage was most prevalent among the 41–60 age groups. The mean age of the usage group was significantly higher (34 years vs. 31 years). There was a statistically significant difference regarding sex, type of rider, and alcohol consumption with the use of the helmet (p< 0.01). All participants with the lowest Glasgow Coma Score were non-helmeted patients, signifying a significant finding (p= 0.014). Nevertheless, there was no statistically significant difference in the Injury Severity Score between helmeted and non-helmeted patients (p= 0.339) (Table 2).
Demographic data of helmeted and non-helmeted motorcyclists
Regarding injury characteristics of the head and neck, there were 154 patients (26%) in the non-helmeted group diagnosed as having a head injury, while there were 124 patients (15%) in the helmeted group. Interestingly, none of the non-helmeted patients sustained neck injuries. In contrast, all instances of neck injuries among the helmeted group were cervical spine injuries, although statistical significance was less pronounced (p= 0.08) (Table 3).
Comparison of injury characteristics between helmeted and non-helmeted motorcyclists
Table 4 presents an analysis of 278 cases comparing head injuries between helmeted and non-helmeted motorcyclists. The incidence of superficial and open wounds was similar between the two groups. Additionally, both groups exhibited the same rate of facial fractures. The most notable difference was observed in intracranial hemorrhage, which was significantly more common among non-helmeted patients (p= 0.047).
Comparison of head injury characteristics between helmeted and non-helmeted motorcyclists (n=278)
Concerning facial fractures, Table 5 indicates that among the 41 individuals in the group diagnosed with facial fractures, the multiple-site fractures group had a slightly higher occurrence rate (56% vs. 44%) compared to the single-site fracture group. The group without helmets had a higher incidence of multiple-site fractures compared to single-site fractures (70% vs. 30%), while the group with helmets had a lower incidence (39% vs. 61%), which was not statistically significant. Based on the single-site fracture group, the non-helmeted patients had a higher occurrence of skull fractures. However, the helmeted patients had a higher frequency of midface fractures, specifically in the orbit, nasal, and zygomaxillary areas, as well as mandibular fractures. In contrast, the non-helmeted group had a higher incidence of upper and midface fractures among the multiple-site fracture patients. Still, the lower face fracture in the multiple-site fracture group was predominant in the helmeted patients. Additionally, panfacial fracture, which is the most severe form of facial fracture, predominantly occurred among non-helmeted groups.
Comparison of facial fracture patterns between helmeted and non-helmeted motorcyclists (n=41)
Participant demographics were compared between individuals with head injuries and those without head injuries. The age of more than 60 years, sex, and rider type were not statistically significantly different in both groups. Notably, non-helmeted wear and alcohol consumption were associated with head injuries at a significantly higher rate. The Glasgow Coma Score and Injury Severity Score also demonstrated strong associations observed in participants with head injuries (Table 6).
Comparison of patient demographics between those with and without head injuries
The bivariate logistic regression analysis showed that the age more than 60 years, male sex, not wearing a helmet, and drinking alcohol were factors that increased the risk of head injuries (odds ratios of 1.72, 1.28, 2.01, and 4.50, respectively), while the rider type was not (Table 7). Multivariable analyses, including the age of more than 60 years, male sex, non-helmet wearing, and alcohol drinking, were performed. The variance inflation factor of all independent factors showed no correlation. The final model, after the backward selection method, revealed that the age more than 60 years, non-helmet wearing, and alcohol drinking were noteworthy factors for head injuries, with an adjusted odds ratio of 2.02, 1.78, and 4.09, respectively (Table 8).
Bivariate analysis of factors associated with head injury
Multivariable analysis of factors associated with head injury
DISCUSSION
This study reported the incidence, patterns, and contributing factors of head and neck injuries associated with motorcycle incidents. The study observed a higher representation of males, which aligns with the distribution patterns reported in previous research [3,5-9]. Approximately 60% of the patients indicated the utilization of helmets, while a mere 12% reported engaging in alcohol consumption, findings that align with previous studies [8-10]. Most patients had a high Glasgow Coma Score and a low Injury Severity Score. This may be attributed to the incident occurring in an area where traffic rules are strictly enforced.
The results strongly affirm the protective benefits of helmets in reducing head injuries among motorcyclists. This is in line with the extensive body of research that has consistently demonstrated the effectiveness of helmets in preventing head injuries [3,4,6,11]. Our study found that helmeted individuals had fewer multiple site and panfacial fractures, and intracranial hemorrhages compared to non-helmeted individuals. The reduced severity of facial fractures among helmeted motorcyclists aligns with findings from other previous studies, which highlighted the protective role of helmets in reducing facial trauma [11-14]. Moreover, the significant reduction in intracranial hemorrhages among helmeted motorcyclists underscores the importance of helmets in mitigating severe and life-threatening head injuries [2,11,13]. Our analysis also revealed a potential association between alcohol consumption and head injuries. Those who reported alcohol use were more than four times as likely to sustain head injuries. This relationship between alcohol and injuries is a well-established concern [8-10]. Alcohol impairs judgment and reaction time, increasing the risk of incidents and injury severity [3,8]. We discovered that more than half of the patients who consumed alcohol were not wearing a helmet at the time of the incident.
Additionally, the study highlights the relationship between helmet use and the type of neck injuries sustained. Notably, no non-helmeted motorcyclists in our study suffered cervical spine injuries, while all neck injuries among helmeted motorcyclists were cervical spine injuries. Although not statistically significant, this trend suggests a potential connection between helmet use and the pattern of neck injuries. However, whether wearing a helmet reduces the incidence of cervical spine damage is debatable. According to reports, wearing a helmet increases the risk of cervical spine injuries [15,16]. Helmets may increase the weight on the head, resulting in higher momentum on the cervical spine and an increased risk of neck flexion and extension following a motorcycle collision, according to one probable explanation. As a result, wearing a helmet during a crash may result in severe neck injuries [15,16]. Other studies have found that wearing a helmet does not enhance the incidence of cervical spine injuries and has a substantial preventive effect against them [17-19]. Another contributing factor identified in this study was the advanced age of individuals, which was observed to elevate the occurrence of head injuries of any nature. Prior research has demonstrated that age has a considerably greater likelihood of experiencing more severe injuries, particularly traumas to the head and chest [20,21]. This could be attributed to the natural decline in self-protective behavior and agility, as well as the fragility of the physical structure.
The study has certain limitations. Firstly, a retrospective review of medical records may introduce selection bias, as patients with less severe injuries who did not visit the hospital may not be included in the dataset. Secondly, conducting the study at a single hospital may limit the generalizability of the findings to a broader population. Moreover, the analysis was based on medical records, which may contain variations in recording practices and potential inaccuracies. Finally, while the study provides valuable insights into the protective role of helmets, it does not consider the specific types and quality of helmets, which can vary in their effectiveness. Future research should explore the impact of different helmet types on injury patterns in Thailand.
Notes
Conflict of interest
No potential conflict of interest relevant to this article was reported.
Funding
None.
Ethical approval
The study was approved by the Ethics Committee of Lerdsin General Hospital (no. LH 651028). Written informed consent for the patient was waived by the Ethics Committee.
Author contributions
Conceptualization; Data curation; Formal analysis: all authors. Methodology: all authors. Writing - original draft: all authors. Writing - review & editing: Papat Sriswadpong, Piyabuth Kittithamvongs. Supervision; Validation: Papat Sriswadpong, Piyabuth Kittithamvongs. All authors read and approved the final manuscript.