Accidents and assaults commonly lead to injuries of orofacial structures such as the craniofacial bones, soft tissues, and teeth. High-risk sports, especially martial arts, bat-and-ball sports, and contact sports, are associated with a high risk of injury to the facial bones and teeth (PETROVIC ET AL. 2016, VIDOVIC-STESEVIC ET AL. 2015, HERSBERGER ET AL. 2012, MENZEL 2010) due to the high speed of play and powerful physical contacts during these sports.
Certain occupations are also associated with an increased risk of injury. Law enforcement officers, for example, are confronted with acts of violence while on duty on a daily basis and can themselves become victims of violence. Although the general crime rate is decreasing in Switzerland, an increase in verbal and physical assaults towards public servants and police officers has been detected (POLIZEILICHE KRIMINALSTATISTIK SCHWEIZ 2018). In particular, an increase in violent assaults can be observed at public events like demonstrations or football games (ELLRICH ET AL. 2012). From 2000 to 2017, the rate quadrupled, corresponding to more than eight crimes against police officers per day in Switzerland (POLIZEILICHE KRIMINALSTATISTIK SCHWEIZ 2018). In Germany, four out of five police officers reported being insulted or verbally abused on duty in the last 6 to 12 months, and one out of every five to six officers had even been physically assaulted in the line of duty (ELLRICH ET AL. 2010). Victimization of police officers has been investigated in multiple studies, whose aim was to provide a detailed description of the perpetrators, victims, situational circumstances and (long-term) consequences of violent assaults (OHLEMACHER ET AL. 2003). Studies describing the police officers’ experience as victims of violence and the severity of their physical injuries, on the other hand, are scarce (BIBERSTEIN ET AL. 2017). Data on facial and dental trauma incurred from violence against police officers are practically non-existent.
The aim of the present study was to generate data on serious general injuries related to police work and work absences and orofacial injuries resulting therefrom. In addition to risk assessment, police officer equipment, injuries resulting from on-duty accidents and their consequences were also evaluated.
Materials and methods
Members of a police corps in northwestern Switzerland (N=1031) were asked to participate in the present study. The majority of persons contacted were uniformed police officers (approximately 700), including 250 traffic safety and patrol officers. The survey was performed in anonymous fashion, independent of influence from the employer.
The aforementioned particular police corps was selected because of its unique location on the border triangle connecting France, Germany and Switzerland. This densely populated international area is home to several small to medium-sized cities (20,000 to 25,000 inhabitants) and greater cities (e.g., Basel city, 178'000 inhabitants and Basel canton, 200'000 inhabitants). In addition to tri-national and cantonal differences in legislation, international pharmaceutical companies based in Basel and diverse migration flows bring many languages and cultures to the region resulting in new challenges for law enforcement every day.
An online questionnaire (generated on the Questback platform, www.unipark.com) was used to collect data from the police officers, which was kept completely anonymous and processed exclusively on University of Basel servers. Participation was voluntary. The participants’ contact data were obtained from the employer, who approved the survey.
The survey period was limited to two months. Four weeks after the start date, all potential participants were sent a reminder letter encouraging them to participate in the study.
The survey was divided into three categories: General questions (age, sex, years of service and job title), leisure time-related questions (risk-taking behavior in recreational activities) and job-related questions (perceived risk of being injured while on duty, perceived inhibition threshold for assaults on police officers, number of line-of-duty injuries (LODIs) sustained, parts of the body (e.g. head, neck, teeth) injured, and satisfaction with police training and equipment). Survey items used for this purpose included closed questions with a single response (YES or NO) or multiple responses as well as questions to be rated on a visual analog scale (VAS), consisting of a 10 cm line with each level measured in millimeters (Table 1).
The number of questions to be answered varied because police officers who had sustained on-duty injuries were asked to give more precise information about these injuries, and those who had not skipped this section and only answered the general questions.
The Ethics Committee of Northwestern and Central Switzerland confirmed that the study complies with the general principles of the Swiss Federal Act on Research Involving Human Beings (Human Research Act, HRA) and the provisions of Article 51, paragraph 2 HRA, and that it is ethically sound (Number EKNZ Req-2018-00001).
Statistical analysis and potential interactions
After data collection, relevant variables such as age, years of police service, sex, line-of-duty injury, resources, training and risk were comparatively analyzed to test for statistical differences between groups and potential interactions. Logistic regression models were used to estimate adjusted odds ratios (OR) with the corresponding 95% confidence intervals (CI) and p-values. In order to control for confounding of the effects, the variables were analyzed stepwise. All regression models were adjusted for the sex of the subject and other relevant variables. When there was no significant interaction effect, p <0.05 was defined as statistically significant. Adjustment of significance levels for multiple comparisons was omitted because of the descriptive nature of the study. All analyses were performed with the R statistical data analysis environment, R version 3.5.1 (R CORE TEAM 2018). Results are expressed as the mean with standard deviation (SD) or median with interquartile range (IQR), depending on the distribution of the variables. The IQR is the range where the middle 50% of the data is located.
A total of 168 (corresponding a response rate of 16.8%) data sets were generated for the present study. The participants were police officers, traffic safety officers and civilian personnel. Twelve respondents (including six civilian employees without public contact) had to be excluded from the analysis, yielding a final sample size of 37 female (23.7%) and 119 male (76.3%) police officers. Other demographic characteristics such as age, years of service, how well-trained they felt they were to handle violent incidents, duration of their longest work absence due to a line-of-duty accident or injury, and whether they had prior martial arts training are summarized in Table 2.
Line-of-duty injuries that led to work absences are evenly distributed across the respective groups for age and years of service. The reported duration of LODI-related work absence was most commonly one day, three days or two weeks, but absences of up to several months were also reported. Most police officers surveyed rated their preparedness training for violent incidents as “good”. Moreover, 42.9% of participants had prior martial arts training before starting police training.
During their free time, the officers had a moderate risk-taking behavior (mean 50, IQR 30-67.2) and a slightly higher level of perceived risk of being injured in the line of duty (mean 59.1, SD 20). Actual line of duty injuries were not uncommon (60.9%).
Perceived threat of violence levels did not differ considerably between police officers who had sustained injuries in the line of duty (mean 40, IQR 20-60) and their colleagues who had not (mean 50, IQR 21.2-60)./p>
In the youngest age group (age 20-30 years), perceived threat levels were significantly lower in individuals who had sustained line-of-duty injuries than in those who had not (Fig. 1). Younger officers differed significantly from their older colleagues in this respect: Perceived threat levels were higher among older officers with duty-related injuries than in those without injuries. The 41-50-year-old age group was the only cohort where a history of on-duty injury did not influence the level of perceived threat.
When asked about the long-term impact of being assaulted and injured in the line of duty on their daily life, 29.7% of the surveyed officers stated that they had permanent impairments after the injury, and 8.2% gave no response.
Dental injuries were reported in only one case (0.6%). The most commonly injured body parts were the hands (20.8%), head (14.9%) and knees (11.3%).
A continuous increase in the number of violent injuries that led to work absences among police officers occurred during the first 15 years of service. In the following years, the number remained constant or increased slightly and, apparently, hardly any new injuries occurred (Fig.
The aim of the present study was to evaluate serious injuries suffered by police officers in a Swiss police corps in the line of duty. Another goal was to identify individual factors that might influence the risk of injury.
168 out of 1031 potential study participants returned completed questionnaire data sets. By comparison, similar studies had response rates of 47.2% and 54% (ELLRICH ET AL. 2010, BIBERSTEIN ET AL. 2017). The response rate in the present study was lower, presumably due to the voluntary nature of participation and the fact that the study was not initiated by a police or political supervisory authority. Nevertheless, the demographic characteristics (gender distribution, reported age and years of service) of this population are comparable to those of similar studies (VIOLANTI ET AL. 2013).
Various group dynamic factors may have influenced the number of participants. For example, conversations among colleagues about participating (or not participating) in the study can affect one's own participation behavior. Another reason is that some police officers who have been victims of violence may not participate in the survey because they do not want to show any signs of weakness. Thirdly, because of the title of the study ("Serious injuries in the line of police duty and their long-term consequences"), many police officers who do not work in direct contact with the public may have felt that the study did not apply to them and did not participate for that reason.
The number of serious physical injuries increased continuously during the first 15 years of service. One reason for this could be that police officers with more years of service often move on to supervisory, organizational or desk jobs and thus have less contact with the public. Secondly, law enforcement agencies refrain from assigning older officers to security duty, if possible. Another study showed that 60% of police officers strive for more self-protection after being injured in the line of duty (JAGER ET AL. 2013). Evidently, increased experience in police work is associated with increased precaution on the part of the individual law enforcement officers, which means more protection on duty.
Confrontations between the police and citizens can occur, especially at public events such as football games and demonstrations. Despite the many-fold increase in these incidents over in recent years (POLIZEILICHE KRIMINALSTATISTIK SCHWEIZ 2018), this evidently is not associated with an increased risk of injury for police officers (Biberstein et al. 2017).
Police officers who have not experienced violent assaults on duty tend to over- or underestimate the risk and danger of injury. Prior experience with violence in the line of duty evidently leads to better appraisal of future and dangerous situations.
In conclusion police officers are aware of their risk of work-related injury. Moreover, with the training and continuing education they had received, they felt that by and large they were well-prepared to de-escalate potential conflict situations and resolve them in the most peaceful way possible.
The number of assaults and injuries incurred during active police duty is increasing, but police officers’ perceived threat of violence is still relatively low. However, long-term physical consequences of line-of-duty injuries are not uncommon. Overall, oral and dental injuries in the line of police duty are rare compared to head injuries.
Special thanks go to Colonel Martin Roth, PhD, for actively supporting this study. His expert knowledge made it possible to realize this research project.