Epidemiology of Cervical Spine Injuries in The Emergency Department at The University Hospital of The West Indies, Jamaica and The Use of Clinical Decision Rules, A Retrospective Review.

Background: Cervical spine injuries are myriad and ubiquitous, however the related demographic information has not been documented for the Jamaican or Caribbean population. These injuries can be life threatening and so it is important for the Emergency Physician to adhere to guidelines which direct management decisions including the need for imaging. This study therefore is an effort to report on the epidemiology of patients with cervical spine injuries presenting to the Emergency Department (ED) at the University Hospital of the West Indies (UHWI) and the use of clinical rules in the diagnosis of these injuries. This was a retrospective study. The log books from the ED at the UHWI were used to identify patients presenting with possible cervical spine injuries from January 1, 2013 to December 31, 2016. Inclusion/exclusion criteria were applied to select study patients. Demographical and clinical information was collected and evaluated. Results: 1,380 charts were identied as possible subjects. Of these, 887 charts were located and 806 (90.9%) were eligible. Ages ranged from 16 to 101 years with an average of 37.5 years. The majority of subjects were male, with a male to female ratio of 3:1. The main causes of these injuries were motor-vehicle collision (46.4%), motor-bike collision (23.8%) and fall from elevation (13.1%). Cervical spine injuries were identied in 20 (2.48%) subjects where motor-vehicle collision (45%) and motor-bike collisions (25%) were the main cause for injuries. Documentation of clinical rules applied to determine the need for radiological testing were present for 37.7% of the study population (NEXUS 36.2%, CCR 0.4% and combination 1.1%) Conclusion: The regarding of which may reduce the occurrence of unnecessary imaging. This study was a retrospective descriptive study. Patients with a cervical spine injury and all patients with a history of head and neck trauma, who presented to the ED at the UHWI from January 1 st, 2013 to December 31 st, 2016 were analyzed. The UHWI is a teaching hospital located in Kingston, Jamaica. Ethical approval was attained from the local ethics committee at the University of the West Indies Faculty of Medical Science. On average 53,000 patients are managed per year in the ED. Other studies surrounding trauma in the Accident and Emergency Department at the UHWI have been explored; however, this is the rst documented study specic to cervical spine injury which has been conducted.


Background
Trauma to the cervical spine can injure the bony elements causing fracture of the vertebra or damage to the neural elements. A spinal cord injury is de ned as any traumatic disruption of the spinal cord, associated with extensive musculoskeletal involvement [1,2]. There are a wide variety of clinical presentations of cervical spine injury found in patients who present to the emergency room, making its diagnosis di cult [3]. Of patients presenting to the Emergency Department (ED) in the United Kingdom, approximately two percent will have a clinically important cervical spine injury caused by blunt trauma, for example motor vehicle collision or fall [4,5]. Spinal trauma is one of the most expensive burdens in the United States. For every fteen to forty persons per million population, 12,000 of these, patient have paraplegia as a result of cervical spine injury. One thousands of these patients, will die during their time of admission, and 4,000 will die before admission [6].
At the University Hospital of the West Indies (UHWI), Jamaica the most commonly injured vertebra in the spine is C6 [7].
Although no national gures are available for cervical spine injuries, an estimated US $70 is the average cost of management of a trauma patient in the ED at the UHWI resulting in an annual cost of USD $578,000 [7]. The development of clinical decision rules, the NEXUS Low-Risk Criteria and the Canadian C-spine Rule (CCR) which guide decisions to clinically clear the cervical spine have assisted Emergency Physicians around the world [3].The purpose of clinically clearing the cervical spine is to avoid missing injury to the spine, prevent permanent damage and extension of damage to the cervical spine and to avoid the many complications of immobilization [8]. With the application of the NEXUS Low-Risk Criteria and the CCR after a physical examination, the number of radiographic studies ordered should decrease.
The aim of this study is to report on the epidemiology of patients with cervical spine injuries and the use of clinical rules in the diagnosis of these injuries. This would determine the usefulness and adherence of the rules in the management of these patients and determine the need to ensure use of the guidelines Method This study was a retrospective descriptive study. Patients with a cervical spine injury and all patients with a history of head and neck trauma, who presented to the ED at the UHWI from January 1 st, 2013 to December 31 st, 2016 were analyzed. The UHWI is a teaching hospital located in Kingston, Jamaica. Ethical approval was attained from the local ethics committee at the University of the West Indies Faculty of Medical Science. On average 53,000 patients are managed per year in the ED. Other studies surrounding trauma in the Accident and Emergency Department at the UHWI have been explored; however, this is the rst documented study speci c to cervical spine injury which has been conducted.
Charts of patients presenting to the ED at the UHWI with a history of head and neck trauma were suitable for the study inclusion. Patients' charts were retrospectively identi ed using the inclusion and exclusion criteria. Patients were included if they were over 16 years old, the injury occured within previous 48 hours and there was associated acute trauma to the head or neck. The risk of cervical spine injury with neck pain or no neck pain alongside one of the following: visible injury located above the clavicles, non-ambulatory, dangerous mechanism of injury were also inclusion criteria. Excluded patients were those with penetrating neck trauma, known to have a vertebral disease, previously evaluated for the same injury or where the injury occurred more than 48 hours prior to presentation.
The charts of all eligible patients were retrospectively reviewed. These patients' information was collected from existing medical records. The information recorded was stored in a secured ling cabinet while studied. As a retrospective study, there was to interference with patient care, and informed consent was not required.
The analysis of this data was done using the Statistical Package for Social Sciences (SPSS). Frequencies and percentages were calculated for categorical data. Parameters were analyzed within categories. The level of signi cance was predetermined at p < 0.05. Using the Raosoft sample size calculator a sample of 800 patients would be needed to yield a clinically important study population.

Patient demographics
A total of 188,714 persons presented to the ED during the period studied. Of these, 1,380 patients were identi ed as possible study subjects, with a total of 806 meeting the inclusion/exclusion criteria for analysis. The appropriate application of a screening tool was applied in 304 (37.8%) patients.
Gender and Age Distribution Figure 1 shows the age and gender distribution of the study population. The age range of the patients was 16 to 101 years, with a mean of 37.5 and a median of 42.5 years. The least number of patients were in the age range of 100 years and over (2 persons). Injuries occurred less frequently in females. More males were involved in trauma, with a male to female ratio of 3:1. Over the age of 79 years, injuries presented more often in females.

Decision Instrument Used with The Participants Studied
The comparisons of the use of the different rules applied in 806 patients studied are depicted in Fig. 2. There was no documentation of the rules being applied in 502 (62.3%) of patients. When comparing the application of the NEXUS Low-Risk Criteria and CCR, they were applied to 292 (36.2%) and 3 (0.4%) patients respectively. The NEXUS Low-Risk Criteria was the rule most frequently used for the assessment of patients. The combination of both NEXUS Low-Risk Criteria and CCR was used in nine patients (1.1%). The CCR was applied in the minority of times.

Demographics of patients with cervical spine injuries
Twenty patients (2.48%) in the study presented with a cervical spine injury Table 2.. The age range was 19-56 years, with a mean of 36.8 years. Males were the predominant gender with a male to female ratio of 6:1. The most common cervical spine fractured was C-6 (nine patients) followed by C-5 and C-7 with four each. The clinical decision rule used most often was the NEXUS Low-Risk Criteria (55%). Due to lack of documentation, the method of cervical spine treatment in the eleven patients is unknown.

Discussion
Road tra c accidents are the second most common cause of admission for trauma to the University Hospital of the West Indies (9). The 2017 annual tra c crash report of Jamaica found 321 persons were killed as a result of 292 motor vehicle crashes (10). Victims of motorcycle collision and motorbike collision sustain serious injuries (9). A study done by Ward et al. examined the cost of violence-related injuries in Jamaica (11). The total cost of violence related injuries in 2014 was JMD $3.6 billion which represents 22% of the health budget of Jamaica. Trauma plays an important role in the nancial burden of the health system (11).
This study showed that the majority of patients (46.4%) presenting with potential cervical spine injury was caused by motor vehicle collisions. The second most common presenting cause was motorbike collisions representing 23.8% of patients. In total 76.7% of the potential injuries were as a result of road tra c accidents. When males were compared to females, males presented more frequently with a ratio of 3:1. This study's ndings is in keeping with other studies done within Jamaica and worldwide.
We found the NEXUS Low-Risk Criteria was used more often than the CCR in deciding the need for radiograph in the emergency department of the University Hospital of the West Indies.
In a study done by Elseton et al., and another done by Poonnoose et al., the overutilization of cervical spine imaging by emergency physicians despite the recommended use of the NEXUS Low-Risk criteria and CCR was found (12).
Overutilization was also shown in this study with the performance of 243 (55%) cervical spine X-Rays in patients without the application of a clinical decision rule.
Of the 806 patients who were studied, 20 (2.48%) of these had a cervical spine injury. The average age of a patient with injury was 36.8 years with a male to female ratio of 6:1. The NEXUS Low-Risk criteria were applied to 11 of these patients, and nine patients had pathologies which were diagnosed without the application of criteria. Motor collisions (motorbike collisions and motor car collisions) were the most common mechanism of injury 14 patients (70%) were the most common mechanism of injury found.
In a study done by Dickinson et al. (n = 8,924), cervical spine injuries were found in 14 (0.16%) patients; this percentage was signi cantly smaller than 2.48% found in this study. The average age of patient with injury was 56.57 years with a male to female ratio of (2:1), this study had an average age of 36.8 years representing a younger population. Fall from height was the most common mechanism to cause injury to the cervical spine; it represented 71.41% in comparison to this study which was represented by motor collision 70.0%. The other two mechanisms of injury in the study by Dickinson et al. were motor vehicle collisions and trampled by horse 21.48% and 7.14% respectively (13).
The cervical spine injuries which resulted from motor collision occurred at C2-7. The injuries caused by motor collisions were, displacements, teardrop fracture, spinous process fracture, facet and laminar fracture, open transverse process fracture, compression fracture, and comminuted fracture. Other injuries associated with motor collision were a frontal bone fracture, subgleal hematoma, fracture of the 5th proximal phalanx, left femur fracture, left forearm fracture, left bula fracture, multiple vertebral fractures, and right femoral fracture.
The two methods of cervical spine treatment used in this study were internal xation and the application of a rigid collar.
Internal xation was applied in four (20%) of patients, and treatment with a rigid collar was documented in only four (20%) of the patients.  (13).
The most common types of injuries to the cervical spine were fractures and dislocations to the C3-7 region (3). Injuries to the cervical spine occur most commonly at two points. One half are found at C5-7 region and one third at C-2 (14). The most common cervical spine vertebrae fracture in this study were C5 and C-6 (45%). A study on spinal injuries done by Bruce et al., at the University Hospital of the West Indies showed C-6 to be the cervical vertebra most commonly fractured, (15). Other common injuries found in the study by Bruce et al., were to the lumbar spine and the thoracic region (15).
In this retrospective study, a limitation was that some of the dockets could not be found. Of 1,380 medical record numbers collected from the Emergency Department logbooks, only 887 dockets were recovered from the library.

Conclusion
In conclusion, cervical spine injuries were more common in this study population when compared to other studies. The main source of injuries was attributed to road tra c accidents which suggests more needs to be done regarding road safety. A clinical decision rule to determine the need for radiological tests were not carried out on the majority of patients resulting in possible overutilization of radiographs. Criteria used in participants studied.