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Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study
Journal of Cranio-Maxillo-Facial Surgery xxx (2013) 1e7
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Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study Ainiwaer Mijiti a, b, Wang Ling a, b, Maimaitituerxun Tuerdi a, b, Abudukelimujiang Maimaiti a, b, Julaiti Tuerxun a, b, Yao Zhi Tao a, b, Adilijiang Saimaiti a, b, Adili Moming a, b, * a Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830054, People’s Republic of China b Stomatology Disease Institute of Xinjiang Uyghur Autonomous Region, Urumqi, Xinjiang 830054, People’s Republic of China
a r t i c l e i n f o
a b s t r a c t
Article history: Paper received 21 November 2012 Accepted 14 May 2013
Purpose: To investigate the epidemiological characteristics of maxillofacial fractures treated at a university hospital, Xinjiang, China over a 5-year period. Patients and methods: Between 2006 and 2010, a total of 1350 patients with maxillofacial fractures were reviewed retrospectively. The data collected included demographics, aetiology, site of fracture, time regarding injuries, presence of associated injuries, treatment modalities, and complications. Results: A total of 1860 maxillofacial fractures were seen in 1350 patients with a male to female ratio of 4.9:1. The most common aetiology of the fractures was motor vehicle accident, followed by interpersonal violence. The age group 21e30 years accounted for the largest subgroup in both sexes. The mandible was the most common site of fracture followed by the zygoma. Associated injuries were found in 48.3% of patients, with a prevalence of intracranial injuries (37.0%). Majority of fractures were treated with open reduction (62.4%), and 7.2% of patients presented post-operative complications. Conclusion: Road traffic accident is the most common cause of maxillofacial fractures in China, which is characterized by an increasing prevalence and resulting in more associated injuries. Thus, more attention should be paid on the prevention and treatment of these injuries caused by road traffic accidents in our country. Ó 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.
Keywords: Maxillofacial fractures Epidemiology Retrospective study Trauma
1. Introduction Maxillofacial fractures are a large public health problem with significant negative impact on an individual’s overall health and even survival. These fractures are relatively common in automobile collisions, with prevalence of 20e60% of all patients involved in road traffic accidents (Ugboko et al., 1998). Despite the legislative changes and preventative measures involving seatbelt and airbag use, as well as the reduction of drinking and driving, road traffic accidents are still the major cause of facial fractures in many developing countries.
* Corresponding author. Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital Xinjiang Medical University, No. 137 South Li Yu-shan Road, New City District Urumqi 830054, Xinjiang Uyghur Autonomous Region, People’s Republic of China. Tel.: þ86 (0) 991 4366161, þ86 (0) 991 4366081, þ86 (0) 13565956278 (mobile). E-mail address: [email protected] (A. Moming).
A great number of authors in various regions have reported the aetiology, fracture characteristics, and treatment pattern of maxillofacial injuries of their patients. Most of the authors described traffic accidents as the primary cause of facial fractures (Li et al., 2006; Al-Khateeb and Abdullah, 2007; Chrcanovic et al., 2012; Naveen Shankar et al., 2012), while some reported violence as the primary cause (Bakardjiev and Pechalova, 2007; Lee et al., 2010). The presentation, severity, and pattern of the maxillofacial fracture will depend on the aetiology, magnitude of the causative force, impact duration, the acceleration imparted by it to the part of the body struck, and the rate of acceleration change (Naveen Shankar et al., 2012). The management of complicated facial fractures is challenging even to the most experienced maxillofacial surgeons, while the presence of coexistent injuries and the complexity of these injuries make it more difficult to consolidate experience and develop realistic treatment protocols. Furthermore, the lack of sufficient specialist facial trauma units results in unacceptable delays from referral to operation, complicating the management and compromising the outcome.
1010-5182/$ e see front matter Ó 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jcms.2013.05.005
Please cite this article in press as: Mijiti A, et al., Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study, Journal of Cranio-Maxillo-Facial Surgery (2013), http://dx.doi.org/10.1016/j.jcms.2013.05.005
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A. Mijiti et al. / Journal of Cranio-Maxillo-Facial Surgery xxx (2013) 1e7
In China, the world’s most populous country, more than 100,000 people die and millions are injured in road traffic accidents or other traumatic mishaps each year, and trauma has become the key aetiological factor of traumatic injuries and deaths in individuals under 35 years old (Song et al., 2006). Xinjiang, the largest autonomous region in China, located in the northwest of the country spans over 1.6 million km2, with a population of 21,813,334 (according to the 2010 year census). It borders with Russia, Mongolia, Kazakhstan, Kyrgyzstan, Tajikistan, Afghanistan, Pakistan, and India. The road, a major means of transportation in Xinjiang, is a key factor in Xinjiang’s economic development. It connects this region with China’s east coast, central and western Asia, plus some parts of Europe. A clearer understanding of the demographic patterns of maxillofacial injuries will assist health care providers as they plan and manage the treatment of traumatic maxillofacial injuries (Al Ahmed et al., 2004). Such epidemiological information can also be used to guide the future funding of public health programs geared towards prevention. To this end, numerous studies have been carried out to explore the epidemiological features of maxillofacial fractures in different population groups. However, to our knowledge there is a lack of reports detailing the causes, incidence, and treatment pattern of maxillofacial injuries in China, and no study has been published about maxillofacial fracture analysis for this region. The main purpose of this study was to investigate the epidemiological characteristics of prevalence, aetiology, sex and age distributions, fracture site, treatment pattern, associated injuries, and complications of maxillofacial fractures treated at the Department of Oral and Maxillofacial Surgery, the First Affiliated Hospital of Xinjiang Medical University, Xinjiang, China, over a 5-year period from January 2006 to December 2010.
91 years old, with a mean age of 31.90 (SD 13.96). No statistically significant difference was observed between male and female mean ages (male 32.05 years; female 31.13 years; P > 0.05). Most of the fractures occurred under 40 years of age, and which accounted for 76.4% of the entire samples. After the third decade of life, the age-specific distribution in patients shows a decreasing incidence with each new decade: 82 injuries (6.1%) occurred in the first decade, 165 (12.2%) in the second, 441 (32.7%) in the third, 344 (25.5%) in the fourth, 191 (14.1%) in the fifth, 89 (6.6%) in the sixth, 29 (2.1%) in the seventh, 9 (0.7%) in the eighth and ninth. The significant majority of (n ¼ 1122, 83.1%) patients are males, and females accounted for 16.9% (n ¼ 228) (M:F ¼ 4.9:1 P < 0.001). The male to female ratio showed significantly higher differences in sports accident and interpersonal violence groups, reaching 12.4:1 for motorcycle accidents. 3.2. Yearly and monthly distribution The yearly distribution of the maxillofacial fractures showed that the incidence tended to be increasing year by year with the highest number of 405 (30.0%) cases in 2010, followed by 2009 with 335 (24.8%) cases; 2008, with 270 (20.0%) cases; 2007, with 211 (15.6%) cases; and 2006, with 129 (9.6%) cases. The monthly distribution showed summer and autumn were the seasons with greatest percentage of maxillofacial fractures with its peak in October. In 2010, most of the 297 (73.3%) fractures occurred during these two seasons, while it was spring and winter for 2009 with 236 (70.4%) cases (Fig. 1). 3.3. Aetiology of maxillofacial fractures
2. Material and methods The medical records of 1350 patients who had sustained maxillofacial fractures and admitted to our hospital from January 2006 to December 2010 were retrospectively reviewed and analyzed. Standardized data was gathered from patients’ medical records included demographics (e.g. age, sex), aetiology of injury, anatomic site of fracture, time of hospital admission and operation, presence and location of associated injuries, treatment pattern, length of in-hospital stay, and complications. Patients with isolated skull fractures were excluded from our study. We also excluded patients who had only minor superficial soft tissue injuries. The patients’ age ranged from 0 to 91 years old, and was divided into 8 age groups: 0e10,11e20, 21e30, 31e40, 41e50, 51e60, 61e70, and over 70 years old. Cause of injury was divided into following ten categories: (1) motor vehicle accident (MVA); (2) interpersonal violence (IPV); (3) fall on the ground; (4) fall from height; (5) motorcycle accident; (6) hit by object; (7) sports accident; (8) bicycle accident; (9) work-related accident; and (10) miscellaneous, which included pathological fractures, coal mine blast injuries, animal attack accident, tooth extraction, and unknown aetiology. Data was analyzed using Statistical Package for the Social Sciences (SPSS) version 19 (IBM, Chicago, IL). The statistical analysis mainly involved descriptive statistics and the Pearson’s Chi-square, a P value less than 0.05 was considered statistically significant. The study was approved by the institutional review board of the Division of Medical Ethnics, the First Affiliated Hospital of Xinjiang Medical University.
The major aetiology of maxillofacial fractures in this study was MVA, which consisting of 42.2% of the total. The second leading cause was IPV with 237 (17.6%) cases, followed by falls on the ground (n ¼ 203, 15.0%). Fig. 2 shows the remaining causes of injury in detail. Both in males and female patients, MVAs were the predominant cause of injury while IPV was mainly for male cases. When the cause of “falls” is considered, the proportion of females who had fracture from falls (31.6%, 72/228) was higher than the proportion of male (19.8%, 222/1122). Pearson Chi-square demonstrated significant statistical association (P < 0.05) between male and female in IV, sports and falls. Regarding the age and aetiology, MVA was the main aetiological factor for all age groups. Aside from MVA, falls were the most
3. Results 3.1. Age and sex distribution During the study period 1350 patients presented maxillofacial fractures. The age of patients at the time of injury ranged from 0 to
Fig. 1. Year and monthly distribution of maxillofacial fractures.
Please cite this article in press as: Mijiti A, et al., Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study, Journal of Cranio-Maxillo-Facial Surgery (2013), http://dx.doi.org/10.1016/j.jcms.2013.05.005
A. Mijiti et al. / Journal of Cranio-Maxillo-Facial Surgery xxx (2013) 1e7
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Fig. 2. Aetiology of maxillofacial fractures in Xinjiang, China from January 2006 to December 2010.
common mechanism of injury (42.6%) in the first decade of life, and there were no injuries related to violence or sports. The largest age group in this study was 21e30 years old, which represented for 32.7% of the entire study population. IPV was the second common cause of injury in this age group (23.1%) and accounted for 43.0% of the IPV occurred. The analysis of MVA, according to the age group, demonstrated that the proportion of patients who had maxillofacial fractures was higher in the age group 31e40 years old (48.5%) than any other age groups. In the fifth, sixth, seventh, and eighth decades of life, MVA was still the most common cause of fractures while falls were responsible for the significant number of injuries (Fig. 3). 3.4. Time between injury to admission and admission to surgery The time elapsed from injury to the admission ranged between 1 and 180 days; however, 540 (40.0%), 129 (9.6%), and 57 (4.2%) patients were seen on the day, the first, and the second day of the trauma, respectively. Of the 829 operated patients, 97 (males ¼ 71, females ¼ 26) (11.7%) received their ORIF on the same day as the
injury, whereas the remaining 732 (88.3%) patients had their operation an average of 5.85 days after the admission. The proportion of patients who had their surgical operation peaked on the fifth day of admission (n ¼ 126, 15.2%), and the cumulative 122 patients had their surgical treatment 10 days after admission. The average period of hospitalization was 9 days (1e60 days; median of 7.5 days). No significant variation in hospitalization period was observed between patients grouped according to trauma aetiology (P > 0.05) (Fig. 4). 3.5. Localization and type of maxillofacial and associated injuries (AIs) The total of 1350 patients presented 1860 maxillofacial fractures, resulting in 1.38 fractures per patient. The commonest site was the mandible. A total of 492 patients (345 isolated and 147 associated with middle third and/or frontal bone) with 614 mandibular fractures were identified (mandible:fractures ¼ 1:1.25), with mandibular body (36.0%) being the most common fracture site followed by symphysis (20.4%), the condyle (18.2%),
Fig. 3. Age and aetiology distribution of maxillofacial fractures.
Please cite this article in press as: Mijiti A, et al., Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study, Journal of Cranio-Maxillo-Facial Surgery (2013), http://dx.doi.org/10.1016/j.jcms.2013.05.005
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Fig. 4. Time between admission and surgery (days).
A total of 895 AIs were observed in 653 (48.3%) of the 1350 patients. Table 2 summarizes the types, main aetiology, and gender distribution of AIs observed. Intracranial injuries (37.0%) were the most common associated injury both in male and female patients followed by ocular injuries. Injuries of the thorax and lower extremities were also commonly diagnosed, while abdomen injuries were seen less frequently (2.2%). AIs were more prevalent in patients who had sustained injuries caused by MVA and those who had undergone fall from height.
and the angle (12.6%). The distribution of fractures according the aetiology of injuries is shown in Table 1. When associate anatomical fracture site with its aetiology, MVA was a predominant cause of all mandibular fractures (38.3%) while IPV and fall from height were the second leading aetiology of fracture of mandibular angle and condyle, respectively. In this study there were 1102 (59.3%) midface fractures in 873 (64.7%) patients. In Table 1 these fractures are listed according to the cause of injury. Zygomatic fractures were most common (27.2%), followed by nasal bone fractures (25.0%) and orbital floor fractures (18.1%). As in mandibular fractures, MVA was the main cause of injury followed by IPV. Both in mandibular and middle third, alveolar fractures were mainly caused by MVA, followed by fall on the ground. One hundred and twenty two patients had skull base and frontal bone fractures, all of which were associated with fracture of mandible or midface, and only ten patients had isolated frontal bone fractures.
3.6. Treatment and post-operative complications The most frequently performed treatment modalities for all patients were open reduction and internal fixation (ORIF) with or without intermaxillary fixation (IMF), followed by the closed reduction and non-surgical treatment. Of these 1860 fractures, 62.4% were treated using open reduction, 27.3% using closed
Table 1 Distribution of maxillofacial fractures in relation to the anatomical site, aetiology, and gender. Region
Mandible
Middle third
Upper third Total
Anatomical site
Symphysis Body Angle Ramus Condyle Coronoid Mandibular dentoalveolar Total Maxillary dentoalveolar Nasal bone Nasoethmoidal complex Maxilla Le fort Zygomatic Orbital Total Skull base and frontal bone
Aetiology of fracture a
Gender
MVA
IPV
FALL
FALL
48 82 33 14 45 3 10 235 8 110 12 123 21 142 94 510 63 808
15 45 19 6 15 0 3 103 1 78 2 21 9 36 39 186 21 310
30 18 4 7 13 0 4 76 8 28 3 20 6 47 26 138 19 233
11 30 7 2 22 1 5 78 5 21 1 18 9 26 10 90 14 182
b
MA
HBO
Sports
BA
WA
M
Male
Female
4 15 3 5 5 0 1 33 1 13 2 15 7 18 10 66 8 107
7 7 2 3 3 0 3 25 2 9 0 8 4 15 9 47 11 83
6 9 1 0 2 0 3 21 1 6 0 7 2 6 4 26 2 49
1 6 3 2 0 0 1 13 1 5 0 3 0 5 3 17 4 34
1 5 4 3 3 0 0 16 0 4 1 1 1 3 4 14 1 31
2 4 1 0 4 1 2 14 0 1 1 2 1 2 1 8 1 23
102 189 65 35 94 4 26 515 21 232 18 169 49 251 164 904 124 1543
23 32 12 7 18 1 6 99 6 43 4 49 11 49 36 198 20 317
Total (%)
All (%)
125 221 77 42 112 5 32 614 27 275 22 218 60 300 200 1102 144 1860
6.7 11.5 4.5 2.3 6.0 0.3 1.7 33.0 1.5 14.8 1.2 12.0 3.0 16.1 11.0 59.3 7.7 100.0
(20.4) (36.0) (12.6) (6.8) (18.2) (0.8) (5.2) (100.0) (2.5) (25.0) (2.0) (19.8) (5.4) (27.2) (18.1) (100.0) (100.0) (100.0)
Abbreviations: MVA ¼ Motor vehicle accident; IPV ¼ Interpersonal violence; MA ¼ Motorcycle accident; HBO ¼ Hit by object; BA ¼ Bicycle accident; WA ¼ Work-related accident; M ¼ Miscellaneous. a Fall on the ground. b Fall from height.
Please cite this article in press as: Mijiti A, et al., Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study, Journal of Cranio-Maxillo-Facial Surgery (2013), http://dx.doi.org/10.1016/j.jcms.2013.05.005
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Table 2 Distribution of associated injuries according to the major aetiology and gender. Gender
Intracranial Ocular Cervical spine Thorax Abdomen injuries Upper Extremities Lower Extremities Others Total (%)
Main aetiology
Male
Female
MVA
IV
Falla
Fallb
MA
Others
Total (%)
269 144 25 72 7 50 161 25 753 (84.1)
56 33 6 12 1 5 19 10 142 (15.9)
156 87 10 33 4 28 71 15 404 (45.1)
47 40 4 14 3 10 15 3 136 (15.2)
21 12 1 2 0 3 10 3 52 (5.8)
56 4 9 11 10 11 37 9 147 (16.4)
19 9 3 6 1 2 5 4 49 (5.5)
32 19 8 14 2 9 18 5 107 (12.0)
331 171 35 80 20 63 156 39 895
(37.0) (19.1) (4.0) (8.9) (2.2) (7.0) (17.4) (4.4) (100.0)
Abbreviations: MVA ¼ Motor vehicle accident; IPV ¼ Interpersonal violence; MA ¼ Motorcycle accident. a Fall on the ground. b Fall from height.
reduction, and 10.3% underwent observation only. ORIF was the main treatment modality for the majority of fractures except for nasal bone, in which closed reduction was applied for most of the fractures. For upper and lower dentoalveolar bone, the fractures were treated largely by IMF followed by the ORIF plus IMF. One hundred and seventy-five comminuted unstable zygomatic fractures were treated using ORIF, while 89 stable zygomatic complex fractures or isolated zygomatic arch fractures were elevated using hook traction or Gillie’s method. ORIF with miniplates was used in 18 naso-orbital-ethmoidal (NOE) fractures and no surgical treatment was applied for the remaining 4 fractures (Table 3). Of these 1350 patients, 97 (7.2%) patients presented one or more local complication and 86% of these were found in open reduction and observation groups. The most common complication was transient intraoral or extraoral soft tissue infection, accounting for 64.8% (63/ 97) cases, followed by disturbed occlusion and ankylosis, which accounted for 25.8% (25/97) and 4.1%(4/97) of the complications observed. Additionally, dehiscences of the operative wound and post-traumatic osteomyelitis were found in the remaining 3 and 2 cases, respectively. 4. Discussion The incidence, aetiology, clinical presentation, and treatment patterns of maxillofacial fractures can be influenced by sociodemographic factors of the population studied. Factors such as geographic region, population density, economic status, and even cultural differences will have a significant impact on the result of the epidemiologic investigations. Most studies have shown that the epidemiological features of maxillofacial fractures vary from one Table 3 Treatment modalities for entire maxillofacial fractures. Fracture type
Mandible Zygomatic bone Nasal bone Orbital Lefort Maxilla Frontal bone Dentoalveolara NOE Total
Closed reduction
Open reduction ORIF
ORIF þ IMF
109 89 200 7 17 24 27 35
364 175 42 163 38 150 105 9 18 1064
85
508
12 97
Nontreatment
Total number of fractures
24 36 33 30 5 44 12 3 4 191
582 300 275 200 60 218 144 59 22 1860
Abbreviations: NOE ¼ Naso-orbital-ethmoidal; ORIF: Open reduction and internal fixation; IMF ¼ Intermaxillary fixation. a Fractures included 32 mandibular and 27 maxillary dentoalveolar.
country to another and even within the same country depending on the prevailing socioeconomic, educational, cultural, and environmental factors (Olasoji et al., 2002; Kieser et al., 2002). A recent study from China reported that the characteristics of paediatric maxillofacial fractures have remained relatively consistent during the past 20 years (Li and Li, 2008), in contrast to our study in which the incidence of maxillofacial injuries, including paediatric maxillofacial fractures have showed an increasing trend during the study period (Fig. 1). This disparity may be explained by different study periods, and distinct geographic features and economic status of these two regions. The aetiology of maxillofacial trauma is another important epidemiological factor that directly affects the incidence, clinical presentation, and treatment modalities of the facial fractures. Our results found that despite the increased use and design of protective devices for motor vehicle occupants, MVAs remain the leading cause of injury. Numerous articles have reported MVAs as the main aetiologic factor in developing counties such as India (Subhashraj et al., 2007), Egypt (Sakr et al., 2006), Brazil (Chrcanovic et al., 2012), Nigeria (Fasola et al., 2003), and United Arab Emirates (AlKhateeb and Abdullah, 2007), whereas interpersonal violence (Lee, 2009a,b), and falls (Walker et al., 2012) were common causes of maxillofacial fractures in many developed nations. In this study, the highest rate (42.2%) of incidence of fractures was caused by MVA, and our findings are constant with results from these developing countries and another previous report from China (Li et al., 2006), in which road traffic accidents accounted for 59.5% of the study samples. Like many countries in the world, MVA occur mainly due to recklessness and negligence of the driver, poor maintenance of vehicles, often driving under the influence of alcohol or drugs, and a complete disregard of traffic laws. As a developing country with a huge population and rapid economic growth, China faces heavy traffic problems characterized by the increase of traffic accidents year by year. How to manage those maxillofacial fractures, with severe associated injuries resulting from traffic accidents, is a challenge for oral and maxillofacial surgeons (Li et al., 2006). Therefore, there is a need to reinforce legislation aimed to prevent MVA and the total enforcement of existing laws to reduce traffic accidents in our country. Another significant aetiological factor was falls which included falls on the ground and falls from height (n ¼ 298, 22.1%). There are several reasons for the relatively higher incidence of facial trauma resulting from falls. Fig. 3 shows that falls on the ground were the second most common cause of facial fractures in children and the elderly. In the rural areas of Xinjiang, most children will participate in many kinds of daily outdoor activities, such as climbing the trees and mountains, without the surveillance of their parents. In general, falls in elderly are also very common due to reduced flexibility,
Please cite this article in press as: Mijiti A, et al., Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study, Journal of Cranio-Maxillo-Facial Surgery (2013), http://dx.doi.org/10.1016/j.jcms.2013.05.005
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loss of balance, poor lighting, and other health conditions such as Parkinson’s disease, Alzheimer’s disease, arthritis, syncope, and epilepsy. In addition, in the urban area, falls from height were responsible for significant number of facial fractures in construction site workers. Age and aetiology distribution of maxillofacial fractures revealed the most vulnerable victims of maxillofacial injures and their relationship with aetiological factors. Like previous studies the age group of 21e30 years counted for the largest subgroup in both sexes (Fasola et al., 2003; Ansari, 2004; Al-Khateeb and Abdullah, 2007). Interestingly, MVA was commonest in the 31e40 age group. This may because people in this age group are most likely to own their private cars and driving license. Sports injuries mainly presented in patients from 11 to 30 years old, whereas in patients above 50 years of age traffic accidents were followed by falls. The high male to female ratio of 4.9:1 among facial injuries victims was similar to other international studies (Sakr et al., 2006; Bakardjiev and Pechalova, 2007; Chrcanovic et al., 2012). The majority of fractures were found in males (almost 85%), most likely due to a higher physical activity by men, as well as because men are more involved in traffic accidents, altercations, and work-related accidents in China. In contrast to other previous reports from Brazil (Chrcanovic et al., 2012) and India (Subhashraj et al., 2007), our study shows a predominant distribution of accidents causing facial fractures on Mondays. One possible explanation for this difference is that 75% of our patients with maxillofacial fractures were transferred to our unit, and majority of them have chosen to be seen on Mondays after a simple debridement and wound closure at regional hospital. Although the monthly distribution of maxillofacial fractures shows great prevalence in summer and autumn months with its peak in October, the frequency of facial fractures showed no significant differences among the seasons of the year. The higher incidence of facial fractures during this period can be explained by the longest holiday of the year (due to national day) and the tourist seasons of Xinjiang. Several authors have reported that decreases in the rate of complications, such as infection (James et al., 1981) and nonunion (Mathog et al., 2000; Li et al., 2006) has been associated with early reduction of facial fractures. However, our findings are in agreement with another study (de Matos et al., 2010) that no correlation has been found between the day of treatment and complication rates. In this study, only 11.7% of the patients received their surgical treatment on the same day as the injury and the mean time between injuries to surgery seems to be quite long. The main reason for delayed management of fractured bone in our study was delays in the patient presentation and/or transferring to our hospital, systemic conditions, and associated injuries. In this study, the most commonly fractured bones were the mandible followed by the zygoma. This is consistent with findings in some other studies (Bakardjiev and Pechalova, 2007; Al-Khateeb and Abdullah, 2007; Van den Bergh et al., 2012). The most common fracture region in the mandible was the body (36.0%), which is largely in agreement with those of previous reports (Adebayo et al., 2003; Ansari, 2004; Al-Khateeb and Abdullah, 2007). In comparison with our study, authors also reported symphysis and/or parasymphysis (Subhashraj et al., 2007), condyle (James et al., 1981; Chrcanovic et al., 2012), and angle (Sakr et al., 2006; Lee et al., 2010) as the most commonly fractured regions of the mandible. In patients with middle and upper third facial fractures, zygomatic bone fractures were most common, and mainly caused by traffic accidents. This rate is higher than that reported in some studies (Al Ahmed et al., 2004; Lee et al., 2010), but lower than that reported in others (Bamjee et al., 1996; Naveen Shankar et al.,
2012). In accordance with our report, Al-Khateeb and Abdullah (2007) found the zygomatic bone (35.6%) was most common location in midface fractures. However, another report by Lee et al. (2010) presented nasal bones as the most frequently fractured bone. One recent study from India (Naveen Shankar et al., 2012) showed that fractures that occur most frequently following assault are the mandible, maxilla, followed by nasal bone fractures. This finding is in contrast to our findings in which assault related injury caused fractures of mandible, nasal bone, followed by orbital bone fractures. Associated injuries are frequent among patients who have sustained facial fractures. In the present study, almost half of the patients (48.3%) had serious associated injuries, in line with reports from other studies (Bamjee et al., 1996; Al-Khateeb and Abdullah, 2007). However, associated injury rates of 53e99.3% in panfacial fractures were, presented in recently published investigation (Follmar et al., 2007). The occurrence of associated injury correlated significantly with trauma mechanism and fracture type; highspeed accidents and severe facial fractures were significant predictors of associated injury (Thorén et al., 2010). Our findings are constant with the result of this study, demonstrating that the associations between occurrence of AIs and aetiology of injuries were statistically significant (P < 0.05). In the past 15 years, changes in maxillofacial trauma management have been strongly influenced by innovations in materials and technology (Laskin and Best, 2000; Adebayo et al., 2003), since objectives such as early recovery, segment stability, and patients’ comfort have been considered paramount in the treatment of maxillofacial fractures (Cabrini Gabrielli et al., 2003). Historically, the proper treatment of fractures was initially performed by applying intraoral wiring and splints. Later, facial fractures were treated with internal fixation using wires and, most recently, rigid osteosynthesis (Chrcanovic et al., 2012). Reports from the United Arab Emirates (Al Ahmed et al., 2004) and Nigeria (Adebayo et al., 2003) confirmed this practice and stated that open reduction and rigid internal fixation of facial fractures has not become popular in most developing countries mainly because of cost. On the other hand, Torgersen and Tornes (1992) advocated that miniplate osteosynthesis has become the standard procedure in their department, being used 4 times more frequently than wire in open reduction and bone fixation. In our study, 62.4% of fractures were treated with open reduction and 27.3% with closed reduction. This is in contrast with the previous studies (Al Ahmed et al., 2004; Bakardjiev and Pechalova, 2007), in which closed reduction was used more frequently. In this study, most of the fractures were treated with open reduction because it can prevent some unwanted consequences such as body weight reduction, poor oral hygiene, speech difficulties, and periodontal disease associated with the closed reduction approach. The complication rate in our study was 7.2%, very close to the results of one Brazilian study (Brasileiro and Passeri, 2006), but lower than that data presented by other authors ranging from 11% (Torgersen and Tornes, 1992) to 12.8% (Zachariades et al., 1993). Transient local infections were the major complication type, accounting for 4.7% of all cases and 64.8% of the complications observed. The characteristics of the fracture locations and degree of bone fragmentation also contribute to the development of postoperative complications (Brasileiro and Passeri, 2006). Our study showed that, most of the infections happened either in patients with comminuted mandibular or NOE complex fracture, or who had been admitted to the hospital a significant time after the primary injury. Based on our extensive literature search, this study is the first and largest comprehensive retrospective study of maxillofacial fractures published in the English-language literature from China.
Please cite this article in press as: Mijiti A, et al., Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study, Journal of Cranio-Maxillo-Facial Surgery (2013), http://dx.doi.org/10.1016/j.jcms.2013.05.005
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One of the major limitations in our study is that, although it can be a representative paper for epidemiological characteristics of maxillofacial fractures that occurred in our region; it is hard to determine the overall trend of maxillofacial fractures in China. Like other retrospective studies this analysis may be subject to information bias due to inaccurate original examination, and incomplete records and documentation. However, the results do provide important information necessary for the development and evaluation of preventative measures aimed at reducing the frequency of facial injuries, mainly due to road traffic accidents in China, where the incidence of road traffic accidents is increasing annually, and the majority of severe maxillofacial injuries occur in these motor vehicle crashes. 5. Conclusion The results of our retrospective study revealed the essential epidemiological features of maxillofacial fractures occurring in China between 2006 and 2010. As the first and largest comprehensive study of maxillofacial injuries in our region; it will provide valuable information for government officials and health care providers on the prevention of road traffic accidents, which is characterized the main, and increasing cause of facial injuries, and additional associated injuries. Based on the epidemiological features of maxillofacial injuries in our region, additional studies with larger sample sizes should be conducted, and close attention should be paid to the prevention and treatment of these injuries caused by road traffic accidents in our country. Funding None declared. Disclosure of any previous publications or submissions with any overlapping information None. Competing interests None. References Adebayo ET, Ajike OS, Adekeye EO: Analysis of the pattern of maxillofacial fractures in Kaduna, Nigeria. Br J Oral Maxillofac Surg 41: 396e400, 2003 Al Ahmed HE, Jaber MA, Abu Fanas SH, Karas M: The pattern of maxillofacial fractures in Sharjah, United Arab Emirates: a review of 230 cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 98: 166e170, 2004 Al-Khateeb T, Abdullah FM: Craniomaxillofacial Injuries in the United Arab Emirates: a retrospective study. J Oral Maxillofac Surg 65: 1094e1101, 2007 Ansari MH: Maxillofacial fractures in Hamedan province, Iran: a retrospective study (1987e2001). J Craniomaxillofac Surg 32: 28e34, 2004 Bakardjiev A, Pechalova P: Maxillofacial fractures in Southern Bulgaria e a retrospective study of 1706 cases. J Craniomaxillofac Surg 35: 147e150, 2007
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Bamjee Y, Lownie JF, Cleaton-Jones PE, Lownie MA: Maxillofacial injuries in a group of South Africans under 18 years of age. Br J Oral Maxillofac Surg 34: 298e302, 1996 Brasileiro BF, Passeri LA: Epidemiological analysis of maxillofacial fractures in Brazil: a 5-year prospective study. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 102: 28e34, 2006 Cabrini Gabrielli MA, Real Gabrielli MF, Marcantonio E, Hochuli-Vieira E: Fixation of mandibular fractures with 2.0 mm miniplates: review of 191 cases. J Oral Maxillofac Surg 61: 430e436, 2003 Chrcanovic BR, Abreu MH, Freire-Maia B, Souza LN: 1,454 mandibular fractures: a 3year study in a hospital in Belo Horizonte, Brazil. J Craniomaxillofac Surg 40: 116e123, 2012 de Matos FP, Arnez MF, Sverzut CE, Trivellato AE: A retrospective study of mandibular fracture in a 40-month period. Int J Oral Maxillofac Surg 39: 10e15, 2010 Fasola AO, Nyako EA, Obiechina AE, Arotiba JT: Trends in the characteristics of maxillofacial fractures in Nigeria. J Oral Maxillofac Surg 61: 1140e1143, 2003 Follmar KE, Debruijn M, Baccarani A, Bruno DA, Mukundan S, Erdmann D, et al: Concomitant injuries in patients with panfacial fractures. J Trauma 63: 831e 835, 2007 James RB, Fredrickson C, Kent JN: Prospective study of mandibular fractures. J Oral Surg 39: 275e281, 1981 Kieser J, Stephenson S, Liston PN, Tong DC, Langley JD: Serious facial fractures in New Zealand from 1979 to 1998. Int J Oral Maxillofac Surg 31: 206e209, 2002 Laskin DM, Best AM: Current trends in the treatment of maxillofacial injuries in the United States. J Oral Maxillofac Surg 58: 207e215, 2000 Lee JH, Cho BK, Park WJ: A 4-year retrospective study of facial fractures on Jeju, Korea. J Craniomaxillofac Surg 38: 192e196, 2010 Lee K: Trend of alcohol involvement in maxillofacial trauma. Oral Surg Oral Med Oral Pathol Oral Radiol 107: 9e13, 2009a Lee KH: Interpersonal violence and facial fractures. J Oral Maxillofac Surg 67: 1878e 1883, 2009b Li Z, Li ZB: Characteristic changes of pediatric maxillofacial fractures in china during the past 20 years. J Oral Maxillofac Surg 66: 2239e2242, 2008 Li Z, Zhang W, Li ZB, Li JR: Abnormal union of mandibular fractures: a review of 84 cases. J Oral Maxillofac Surg 64: 1225e1231, 2006 Mathog RH, Toma V, Clayman L, Wolf S: Nonunion of the mandible: an analysis of contributing factors. J Oral Maxillofac Surg 58: 746e752, 2000 Naveen Shankar A, Naveen Shankar V, Hegde N, Sharma, Prasad R: The pattern of the maxillofacial fractures e a multicentre retrospective study. J Craniomaxillofac Surg 40: 675e679, 2012 Olasoji HO, Tahir A, Arotiba GT: Changing picture of facial fractures in northern Nigeria. Br J Oral Maxillofac Surg 40: 140e143, 2002 Sakr K, Farag IA, Zeitoun IM: Review of 509 mandibular fractures treated at the University Hospital, Alexandria, Egypt. Br J Oral Maxillofac Surg 44: 107e111, 2006 Song LY, Dong TW, Wei LS, Liu L: Retrospective analysis of 3958 patients with facial injuries. Chin J Stomatol 41: 385e387, 2006 [in Chinese] Subhashraj K, Nandakumar N, Ravindran C: Review of maxillofacial injuries in Chennai, India: a study of 2748 cases. Br J Oral Maxillofac Surg 45: 637e639, 2007 Thorén H, Snäll J, Salo J, Suominen-Taipale L, Kormi E, Lindqvist C, et al: Occurrence and types of associated injuries in patients with fractures of the facial bones. J Oral Maxillofac Surg 68: 805e810, 2010 Torgersen S, Tornes K: Maxillofacial fractures in a Norwegian district. Int J Oral Maxillofac Surg 21: 335e338, 1992 Ugboko VI, Odusanya SA, Fagade OO: Maxillofacial fractures in a semi-urban Nigerian teaching hospital. A review of 442 cases. Int J Oral Maxillofac Surg 27: 286e289, 1998 Van den Bergh B, Karagozoglu KH, Heymans MW, Forouzanfar T: Aetiology and incidence of maxillofacial trauma in Amsterdam: a retrospective analysis of 579 patients. J Craniomaxillofac Surg 40: 165e169, 2012 Walker TW, Byrne S, Donnellan J, McArdle N, Kerin MJ, McCann PJ: West of Ireland facial injury study. Part 1. Br J Oral Maxillofac Surg 50: 631e635, 2012 Zachariades N, Papademetriou I, Rallis G: Complications associated with rigid internal fixation of facial bone fractures. J Oral Maxillofac Surg 51: 275e278, 1993
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Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study Ainiwaer Mijiti a, b, Wang Ling a, b, Maimaitituerxun Tuerdi a, b, Abudukelimujiang Maimaiti a, b, Julaiti Tuerxun a, b, Yao Zhi Tao a, b, Adilijiang Saimaiti a, b, Adili Moming a, b, * a Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830054, People’s Republic of China b Stomatology Disease Institute of Xinjiang Uyghur Autonomous Region, Urumqi, Xinjiang 830054, People’s Republic of China
a r t i c l e i n f o
a b s t r a c t
Article history: Paper received 21 November 2012 Accepted 14 May 2013
Purpose: To investigate the epidemiological characteristics of maxillofacial fractures treated at a university hospital, Xinjiang, China over a 5-year period. Patients and methods: Between 2006 and 2010, a total of 1350 patients with maxillofacial fractures were reviewed retrospectively. The data collected included demographics, aetiology, site of fracture, time regarding injuries, presence of associated injuries, treatment modalities, and complications. Results: A total of 1860 maxillofacial fractures were seen in 1350 patients with a male to female ratio of 4.9:1. The most common aetiology of the fractures was motor vehicle accident, followed by interpersonal violence. The age group 21e30 years accounted for the largest subgroup in both sexes. The mandible was the most common site of fracture followed by the zygoma. Associated injuries were found in 48.3% of patients, with a prevalence of intracranial injuries (37.0%). Majority of fractures were treated with open reduction (62.4%), and 7.2% of patients presented post-operative complications. Conclusion: Road traffic accident is the most common cause of maxillofacial fractures in China, which is characterized by an increasing prevalence and resulting in more associated injuries. Thus, more attention should be paid on the prevention and treatment of these injuries caused by road traffic accidents in our country. Ó 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.
Keywords: Maxillofacial fractures Epidemiology Retrospective study Trauma
1. Introduction Maxillofacial fractures are a large public health problem with significant negative impact on an individual’s overall health and even survival. These fractures are relatively common in automobile collisions, with prevalence of 20e60% of all patients involved in road traffic accidents (Ugboko et al., 1998). Despite the legislative changes and preventative measures involving seatbelt and airbag use, as well as the reduction of drinking and driving, road traffic accidents are still the major cause of facial fractures in many developing countries.
* Corresponding author. Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital Xinjiang Medical University, No. 137 South Li Yu-shan Road, New City District Urumqi 830054, Xinjiang Uyghur Autonomous Region, People’s Republic of China. Tel.: þ86 (0) 991 4366161, þ86 (0) 991 4366081, þ86 (0) 13565956278 (mobile). E-mail address: [email protected] (A. Moming).
A great number of authors in various regions have reported the aetiology, fracture characteristics, and treatment pattern of maxillofacial injuries of their patients. Most of the authors described traffic accidents as the primary cause of facial fractures (Li et al., 2006; Al-Khateeb and Abdullah, 2007; Chrcanovic et al., 2012; Naveen Shankar et al., 2012), while some reported violence as the primary cause (Bakardjiev and Pechalova, 2007; Lee et al., 2010). The presentation, severity, and pattern of the maxillofacial fracture will depend on the aetiology, magnitude of the causative force, impact duration, the acceleration imparted by it to the part of the body struck, and the rate of acceleration change (Naveen Shankar et al., 2012). The management of complicated facial fractures is challenging even to the most experienced maxillofacial surgeons, while the presence of coexistent injuries and the complexity of these injuries make it more difficult to consolidate experience and develop realistic treatment protocols. Furthermore, the lack of sufficient specialist facial trauma units results in unacceptable delays from referral to operation, complicating the management and compromising the outcome.
1010-5182/$ e see front matter Ó 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jcms.2013.05.005
Please cite this article in press as: Mijiti A, et al., Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study, Journal of Cranio-Maxillo-Facial Surgery (2013), http://dx.doi.org/10.1016/j.jcms.2013.05.005
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In China, the world’s most populous country, more than 100,000 people die and millions are injured in road traffic accidents or other traumatic mishaps each year, and trauma has become the key aetiological factor of traumatic injuries and deaths in individuals under 35 years old (Song et al., 2006). Xinjiang, the largest autonomous region in China, located in the northwest of the country spans over 1.6 million km2, with a population of 21,813,334 (according to the 2010 year census). It borders with Russia, Mongolia, Kazakhstan, Kyrgyzstan, Tajikistan, Afghanistan, Pakistan, and India. The road, a major means of transportation in Xinjiang, is a key factor in Xinjiang’s economic development. It connects this region with China’s east coast, central and western Asia, plus some parts of Europe. A clearer understanding of the demographic patterns of maxillofacial injuries will assist health care providers as they plan and manage the treatment of traumatic maxillofacial injuries (Al Ahmed et al., 2004). Such epidemiological information can also be used to guide the future funding of public health programs geared towards prevention. To this end, numerous studies have been carried out to explore the epidemiological features of maxillofacial fractures in different population groups. However, to our knowledge there is a lack of reports detailing the causes, incidence, and treatment pattern of maxillofacial injuries in China, and no study has been published about maxillofacial fracture analysis for this region. The main purpose of this study was to investigate the epidemiological characteristics of prevalence, aetiology, sex and age distributions, fracture site, treatment pattern, associated injuries, and complications of maxillofacial fractures treated at the Department of Oral and Maxillofacial Surgery, the First Affiliated Hospital of Xinjiang Medical University, Xinjiang, China, over a 5-year period from January 2006 to December 2010.
91 years old, with a mean age of 31.90 (SD 13.96). No statistically significant difference was observed between male and female mean ages (male 32.05 years; female 31.13 years; P > 0.05). Most of the fractures occurred under 40 years of age, and which accounted for 76.4% of the entire samples. After the third decade of life, the age-specific distribution in patients shows a decreasing incidence with each new decade: 82 injuries (6.1%) occurred in the first decade, 165 (12.2%) in the second, 441 (32.7%) in the third, 344 (25.5%) in the fourth, 191 (14.1%) in the fifth, 89 (6.6%) in the sixth, 29 (2.1%) in the seventh, 9 (0.7%) in the eighth and ninth. The significant majority of (n ¼ 1122, 83.1%) patients are males, and females accounted for 16.9% (n ¼ 228) (M:F ¼ 4.9:1 P < 0.001). The male to female ratio showed significantly higher differences in sports accident and interpersonal violence groups, reaching 12.4:1 for motorcycle accidents. 3.2. Yearly and monthly distribution The yearly distribution of the maxillofacial fractures showed that the incidence tended to be increasing year by year with the highest number of 405 (30.0%) cases in 2010, followed by 2009 with 335 (24.8%) cases; 2008, with 270 (20.0%) cases; 2007, with 211 (15.6%) cases; and 2006, with 129 (9.6%) cases. The monthly distribution showed summer and autumn were the seasons with greatest percentage of maxillofacial fractures with its peak in October. In 2010, most of the 297 (73.3%) fractures occurred during these two seasons, while it was spring and winter for 2009 with 236 (70.4%) cases (Fig. 1). 3.3. Aetiology of maxillofacial fractures
2. Material and methods The medical records of 1350 patients who had sustained maxillofacial fractures and admitted to our hospital from January 2006 to December 2010 were retrospectively reviewed and analyzed. Standardized data was gathered from patients’ medical records included demographics (e.g. age, sex), aetiology of injury, anatomic site of fracture, time of hospital admission and operation, presence and location of associated injuries, treatment pattern, length of in-hospital stay, and complications. Patients with isolated skull fractures were excluded from our study. We also excluded patients who had only minor superficial soft tissue injuries. The patients’ age ranged from 0 to 91 years old, and was divided into 8 age groups: 0e10,11e20, 21e30, 31e40, 41e50, 51e60, 61e70, and over 70 years old. Cause of injury was divided into following ten categories: (1) motor vehicle accident (MVA); (2) interpersonal violence (IPV); (3) fall on the ground; (4) fall from height; (5) motorcycle accident; (6) hit by object; (7) sports accident; (8) bicycle accident; (9) work-related accident; and (10) miscellaneous, which included pathological fractures, coal mine blast injuries, animal attack accident, tooth extraction, and unknown aetiology. Data was analyzed using Statistical Package for the Social Sciences (SPSS) version 19 (IBM, Chicago, IL). The statistical analysis mainly involved descriptive statistics and the Pearson’s Chi-square, a P value less than 0.05 was considered statistically significant. The study was approved by the institutional review board of the Division of Medical Ethnics, the First Affiliated Hospital of Xinjiang Medical University.
The major aetiology of maxillofacial fractures in this study was MVA, which consisting of 42.2% of the total. The second leading cause was IPV with 237 (17.6%) cases, followed by falls on the ground (n ¼ 203, 15.0%). Fig. 2 shows the remaining causes of injury in detail. Both in males and female patients, MVAs were the predominant cause of injury while IPV was mainly for male cases. When the cause of “falls” is considered, the proportion of females who had fracture from falls (31.6%, 72/228) was higher than the proportion of male (19.8%, 222/1122). Pearson Chi-square demonstrated significant statistical association (P < 0.05) between male and female in IV, sports and falls. Regarding the age and aetiology, MVA was the main aetiological factor for all age groups. Aside from MVA, falls were the most
3. Results 3.1. Age and sex distribution During the study period 1350 patients presented maxillofacial fractures. The age of patients at the time of injury ranged from 0 to
Fig. 1. Year and monthly distribution of maxillofacial fractures.
Please cite this article in press as: Mijiti A, et al., Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study, Journal of Cranio-Maxillo-Facial Surgery (2013), http://dx.doi.org/10.1016/j.jcms.2013.05.005
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Fig. 2. Aetiology of maxillofacial fractures in Xinjiang, China from January 2006 to December 2010.
common mechanism of injury (42.6%) in the first decade of life, and there were no injuries related to violence or sports. The largest age group in this study was 21e30 years old, which represented for 32.7% of the entire study population. IPV was the second common cause of injury in this age group (23.1%) and accounted for 43.0% of the IPV occurred. The analysis of MVA, according to the age group, demonstrated that the proportion of patients who had maxillofacial fractures was higher in the age group 31e40 years old (48.5%) than any other age groups. In the fifth, sixth, seventh, and eighth decades of life, MVA was still the most common cause of fractures while falls were responsible for the significant number of injuries (Fig. 3). 3.4. Time between injury to admission and admission to surgery The time elapsed from injury to the admission ranged between 1 and 180 days; however, 540 (40.0%), 129 (9.6%), and 57 (4.2%) patients were seen on the day, the first, and the second day of the trauma, respectively. Of the 829 operated patients, 97 (males ¼ 71, females ¼ 26) (11.7%) received their ORIF on the same day as the
injury, whereas the remaining 732 (88.3%) patients had their operation an average of 5.85 days after the admission. The proportion of patients who had their surgical operation peaked on the fifth day of admission (n ¼ 126, 15.2%), and the cumulative 122 patients had their surgical treatment 10 days after admission. The average period of hospitalization was 9 days (1e60 days; median of 7.5 days). No significant variation in hospitalization period was observed between patients grouped according to trauma aetiology (P > 0.05) (Fig. 4). 3.5. Localization and type of maxillofacial and associated injuries (AIs) The total of 1350 patients presented 1860 maxillofacial fractures, resulting in 1.38 fractures per patient. The commonest site was the mandible. A total of 492 patients (345 isolated and 147 associated with middle third and/or frontal bone) with 614 mandibular fractures were identified (mandible:fractures ¼ 1:1.25), with mandibular body (36.0%) being the most common fracture site followed by symphysis (20.4%), the condyle (18.2%),
Fig. 3. Age and aetiology distribution of maxillofacial fractures.
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Fig. 4. Time between admission and surgery (days).
A total of 895 AIs were observed in 653 (48.3%) of the 1350 patients. Table 2 summarizes the types, main aetiology, and gender distribution of AIs observed. Intracranial injuries (37.0%) were the most common associated injury both in male and female patients followed by ocular injuries. Injuries of the thorax and lower extremities were also commonly diagnosed, while abdomen injuries were seen less frequently (2.2%). AIs were more prevalent in patients who had sustained injuries caused by MVA and those who had undergone fall from height.
and the angle (12.6%). The distribution of fractures according the aetiology of injuries is shown in Table 1. When associate anatomical fracture site with its aetiology, MVA was a predominant cause of all mandibular fractures (38.3%) while IPV and fall from height were the second leading aetiology of fracture of mandibular angle and condyle, respectively. In this study there were 1102 (59.3%) midface fractures in 873 (64.7%) patients. In Table 1 these fractures are listed according to the cause of injury. Zygomatic fractures were most common (27.2%), followed by nasal bone fractures (25.0%) and orbital floor fractures (18.1%). As in mandibular fractures, MVA was the main cause of injury followed by IPV. Both in mandibular and middle third, alveolar fractures were mainly caused by MVA, followed by fall on the ground. One hundred and twenty two patients had skull base and frontal bone fractures, all of which were associated with fracture of mandible or midface, and only ten patients had isolated frontal bone fractures.
3.6. Treatment and post-operative complications The most frequently performed treatment modalities for all patients were open reduction and internal fixation (ORIF) with or without intermaxillary fixation (IMF), followed by the closed reduction and non-surgical treatment. Of these 1860 fractures, 62.4% were treated using open reduction, 27.3% using closed
Table 1 Distribution of maxillofacial fractures in relation to the anatomical site, aetiology, and gender. Region
Mandible
Middle third
Upper third Total
Anatomical site
Symphysis Body Angle Ramus Condyle Coronoid Mandibular dentoalveolar Total Maxillary dentoalveolar Nasal bone Nasoethmoidal complex Maxilla Le fort Zygomatic Orbital Total Skull base and frontal bone
Aetiology of fracture a
Gender
MVA
IPV
FALL
FALL
48 82 33 14 45 3 10 235 8 110 12 123 21 142 94 510 63 808
15 45 19 6 15 0 3 103 1 78 2 21 9 36 39 186 21 310
30 18 4 7 13 0 4 76 8 28 3 20 6 47 26 138 19 233
11 30 7 2 22 1 5 78 5 21 1 18 9 26 10 90 14 182
b
MA
HBO
Sports
BA
WA
M
Male
Female
4 15 3 5 5 0 1 33 1 13 2 15 7 18 10 66 8 107
7 7 2 3 3 0 3 25 2 9 0 8 4 15 9 47 11 83
6 9 1 0 2 0 3 21 1 6 0 7 2 6 4 26 2 49
1 6 3 2 0 0 1 13 1 5 0 3 0 5 3 17 4 34
1 5 4 3 3 0 0 16 0 4 1 1 1 3 4 14 1 31
2 4 1 0 4 1 2 14 0 1 1 2 1 2 1 8 1 23
102 189 65 35 94 4 26 515 21 232 18 169 49 251 164 904 124 1543
23 32 12 7 18 1 6 99 6 43 4 49 11 49 36 198 20 317
Total (%)
All (%)
125 221 77 42 112 5 32 614 27 275 22 218 60 300 200 1102 144 1860
6.7 11.5 4.5 2.3 6.0 0.3 1.7 33.0 1.5 14.8 1.2 12.0 3.0 16.1 11.0 59.3 7.7 100.0
(20.4) (36.0) (12.6) (6.8) (18.2) (0.8) (5.2) (100.0) (2.5) (25.0) (2.0) (19.8) (5.4) (27.2) (18.1) (100.0) (100.0) (100.0)
Abbreviations: MVA ¼ Motor vehicle accident; IPV ¼ Interpersonal violence; MA ¼ Motorcycle accident; HBO ¼ Hit by object; BA ¼ Bicycle accident; WA ¼ Work-related accident; M ¼ Miscellaneous. a Fall on the ground. b Fall from height.
Please cite this article in press as: Mijiti A, et al., Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study, Journal of Cranio-Maxillo-Facial Surgery (2013), http://dx.doi.org/10.1016/j.jcms.2013.05.005
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Table 2 Distribution of associated injuries according to the major aetiology and gender. Gender
Intracranial Ocular Cervical spine Thorax Abdomen injuries Upper Extremities Lower Extremities Others Total (%)
Main aetiology
Male
Female
MVA
IV
Falla
Fallb
MA
Others
Total (%)
269 144 25 72 7 50 161 25 753 (84.1)
56 33 6 12 1 5 19 10 142 (15.9)
156 87 10 33 4 28 71 15 404 (45.1)
47 40 4 14 3 10 15 3 136 (15.2)
21 12 1 2 0 3 10 3 52 (5.8)
56 4 9 11 10 11 37 9 147 (16.4)
19 9 3 6 1 2 5 4 49 (5.5)
32 19 8 14 2 9 18 5 107 (12.0)
331 171 35 80 20 63 156 39 895
(37.0) (19.1) (4.0) (8.9) (2.2) (7.0) (17.4) (4.4) (100.0)
Abbreviations: MVA ¼ Motor vehicle accident; IPV ¼ Interpersonal violence; MA ¼ Motorcycle accident. a Fall on the ground. b Fall from height.
reduction, and 10.3% underwent observation only. ORIF was the main treatment modality for the majority of fractures except for nasal bone, in which closed reduction was applied for most of the fractures. For upper and lower dentoalveolar bone, the fractures were treated largely by IMF followed by the ORIF plus IMF. One hundred and seventy-five comminuted unstable zygomatic fractures were treated using ORIF, while 89 stable zygomatic complex fractures or isolated zygomatic arch fractures were elevated using hook traction or Gillie’s method. ORIF with miniplates was used in 18 naso-orbital-ethmoidal (NOE) fractures and no surgical treatment was applied for the remaining 4 fractures (Table 3). Of these 1350 patients, 97 (7.2%) patients presented one or more local complication and 86% of these were found in open reduction and observation groups. The most common complication was transient intraoral or extraoral soft tissue infection, accounting for 64.8% (63/ 97) cases, followed by disturbed occlusion and ankylosis, which accounted for 25.8% (25/97) and 4.1%(4/97) of the complications observed. Additionally, dehiscences of the operative wound and post-traumatic osteomyelitis were found in the remaining 3 and 2 cases, respectively. 4. Discussion The incidence, aetiology, clinical presentation, and treatment patterns of maxillofacial fractures can be influenced by sociodemographic factors of the population studied. Factors such as geographic region, population density, economic status, and even cultural differences will have a significant impact on the result of the epidemiologic investigations. Most studies have shown that the epidemiological features of maxillofacial fractures vary from one Table 3 Treatment modalities for entire maxillofacial fractures. Fracture type
Mandible Zygomatic bone Nasal bone Orbital Lefort Maxilla Frontal bone Dentoalveolara NOE Total
Closed reduction
Open reduction ORIF
ORIF þ IMF
109 89 200 7 17 24 27 35
364 175 42 163 38 150 105 9 18 1064
85
508
12 97
Nontreatment
Total number of fractures
24 36 33 30 5 44 12 3 4 191
582 300 275 200 60 218 144 59 22 1860
Abbreviations: NOE ¼ Naso-orbital-ethmoidal; ORIF: Open reduction and internal fixation; IMF ¼ Intermaxillary fixation. a Fractures included 32 mandibular and 27 maxillary dentoalveolar.
country to another and even within the same country depending on the prevailing socioeconomic, educational, cultural, and environmental factors (Olasoji et al., 2002; Kieser et al., 2002). A recent study from China reported that the characteristics of paediatric maxillofacial fractures have remained relatively consistent during the past 20 years (Li and Li, 2008), in contrast to our study in which the incidence of maxillofacial injuries, including paediatric maxillofacial fractures have showed an increasing trend during the study period (Fig. 1). This disparity may be explained by different study periods, and distinct geographic features and economic status of these two regions. The aetiology of maxillofacial trauma is another important epidemiological factor that directly affects the incidence, clinical presentation, and treatment modalities of the facial fractures. Our results found that despite the increased use and design of protective devices for motor vehicle occupants, MVAs remain the leading cause of injury. Numerous articles have reported MVAs as the main aetiologic factor in developing counties such as India (Subhashraj et al., 2007), Egypt (Sakr et al., 2006), Brazil (Chrcanovic et al., 2012), Nigeria (Fasola et al., 2003), and United Arab Emirates (AlKhateeb and Abdullah, 2007), whereas interpersonal violence (Lee, 2009a,b), and falls (Walker et al., 2012) were common causes of maxillofacial fractures in many developed nations. In this study, the highest rate (42.2%) of incidence of fractures was caused by MVA, and our findings are constant with results from these developing countries and another previous report from China (Li et al., 2006), in which road traffic accidents accounted for 59.5% of the study samples. Like many countries in the world, MVA occur mainly due to recklessness and negligence of the driver, poor maintenance of vehicles, often driving under the influence of alcohol or drugs, and a complete disregard of traffic laws. As a developing country with a huge population and rapid economic growth, China faces heavy traffic problems characterized by the increase of traffic accidents year by year. How to manage those maxillofacial fractures, with severe associated injuries resulting from traffic accidents, is a challenge for oral and maxillofacial surgeons (Li et al., 2006). Therefore, there is a need to reinforce legislation aimed to prevent MVA and the total enforcement of existing laws to reduce traffic accidents in our country. Another significant aetiological factor was falls which included falls on the ground and falls from height (n ¼ 298, 22.1%). There are several reasons for the relatively higher incidence of facial trauma resulting from falls. Fig. 3 shows that falls on the ground were the second most common cause of facial fractures in children and the elderly. In the rural areas of Xinjiang, most children will participate in many kinds of daily outdoor activities, such as climbing the trees and mountains, without the surveillance of their parents. In general, falls in elderly are also very common due to reduced flexibility,
Please cite this article in press as: Mijiti A, et al., Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study, Journal of Cranio-Maxillo-Facial Surgery (2013), http://dx.doi.org/10.1016/j.jcms.2013.05.005
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loss of balance, poor lighting, and other health conditions such as Parkinson’s disease, Alzheimer’s disease, arthritis, syncope, and epilepsy. In addition, in the urban area, falls from height were responsible for significant number of facial fractures in construction site workers. Age and aetiology distribution of maxillofacial fractures revealed the most vulnerable victims of maxillofacial injures and their relationship with aetiological factors. Like previous studies the age group of 21e30 years counted for the largest subgroup in both sexes (Fasola et al., 2003; Ansari, 2004; Al-Khateeb and Abdullah, 2007). Interestingly, MVA was commonest in the 31e40 age group. This may because people in this age group are most likely to own their private cars and driving license. Sports injuries mainly presented in patients from 11 to 30 years old, whereas in patients above 50 years of age traffic accidents were followed by falls. The high male to female ratio of 4.9:1 among facial injuries victims was similar to other international studies (Sakr et al., 2006; Bakardjiev and Pechalova, 2007; Chrcanovic et al., 2012). The majority of fractures were found in males (almost 85%), most likely due to a higher physical activity by men, as well as because men are more involved in traffic accidents, altercations, and work-related accidents in China. In contrast to other previous reports from Brazil (Chrcanovic et al., 2012) and India (Subhashraj et al., 2007), our study shows a predominant distribution of accidents causing facial fractures on Mondays. One possible explanation for this difference is that 75% of our patients with maxillofacial fractures were transferred to our unit, and majority of them have chosen to be seen on Mondays after a simple debridement and wound closure at regional hospital. Although the monthly distribution of maxillofacial fractures shows great prevalence in summer and autumn months with its peak in October, the frequency of facial fractures showed no significant differences among the seasons of the year. The higher incidence of facial fractures during this period can be explained by the longest holiday of the year (due to national day) and the tourist seasons of Xinjiang. Several authors have reported that decreases in the rate of complications, such as infection (James et al., 1981) and nonunion (Mathog et al., 2000; Li et al., 2006) has been associated with early reduction of facial fractures. However, our findings are in agreement with another study (de Matos et al., 2010) that no correlation has been found between the day of treatment and complication rates. In this study, only 11.7% of the patients received their surgical treatment on the same day as the injury and the mean time between injuries to surgery seems to be quite long. The main reason for delayed management of fractured bone in our study was delays in the patient presentation and/or transferring to our hospital, systemic conditions, and associated injuries. In this study, the most commonly fractured bones were the mandible followed by the zygoma. This is consistent with findings in some other studies (Bakardjiev and Pechalova, 2007; Al-Khateeb and Abdullah, 2007; Van den Bergh et al., 2012). The most common fracture region in the mandible was the body (36.0%), which is largely in agreement with those of previous reports (Adebayo et al., 2003; Ansari, 2004; Al-Khateeb and Abdullah, 2007). In comparison with our study, authors also reported symphysis and/or parasymphysis (Subhashraj et al., 2007), condyle (James et al., 1981; Chrcanovic et al., 2012), and angle (Sakr et al., 2006; Lee et al., 2010) as the most commonly fractured regions of the mandible. In patients with middle and upper third facial fractures, zygomatic bone fractures were most common, and mainly caused by traffic accidents. This rate is higher than that reported in some studies (Al Ahmed et al., 2004; Lee et al., 2010), but lower than that reported in others (Bamjee et al., 1996; Naveen Shankar et al.,
2012). In accordance with our report, Al-Khateeb and Abdullah (2007) found the zygomatic bone (35.6%) was most common location in midface fractures. However, another report by Lee et al. (2010) presented nasal bones as the most frequently fractured bone. One recent study from India (Naveen Shankar et al., 2012) showed that fractures that occur most frequently following assault are the mandible, maxilla, followed by nasal bone fractures. This finding is in contrast to our findings in which assault related injury caused fractures of mandible, nasal bone, followed by orbital bone fractures. Associated injuries are frequent among patients who have sustained facial fractures. In the present study, almost half of the patients (48.3%) had serious associated injuries, in line with reports from other studies (Bamjee et al., 1996; Al-Khateeb and Abdullah, 2007). However, associated injury rates of 53e99.3% in panfacial fractures were, presented in recently published investigation (Follmar et al., 2007). The occurrence of associated injury correlated significantly with trauma mechanism and fracture type; highspeed accidents and severe facial fractures were significant predictors of associated injury (Thorén et al., 2010). Our findings are constant with the result of this study, demonstrating that the associations between occurrence of AIs and aetiology of injuries were statistically significant (P < 0.05). In the past 15 years, changes in maxillofacial trauma management have been strongly influenced by innovations in materials and technology (Laskin and Best, 2000; Adebayo et al., 2003), since objectives such as early recovery, segment stability, and patients’ comfort have been considered paramount in the treatment of maxillofacial fractures (Cabrini Gabrielli et al., 2003). Historically, the proper treatment of fractures was initially performed by applying intraoral wiring and splints. Later, facial fractures were treated with internal fixation using wires and, most recently, rigid osteosynthesis (Chrcanovic et al., 2012). Reports from the United Arab Emirates (Al Ahmed et al., 2004) and Nigeria (Adebayo et al., 2003) confirmed this practice and stated that open reduction and rigid internal fixation of facial fractures has not become popular in most developing countries mainly because of cost. On the other hand, Torgersen and Tornes (1992) advocated that miniplate osteosynthesis has become the standard procedure in their department, being used 4 times more frequently than wire in open reduction and bone fixation. In our study, 62.4% of fractures were treated with open reduction and 27.3% with closed reduction. This is in contrast with the previous studies (Al Ahmed et al., 2004; Bakardjiev and Pechalova, 2007), in which closed reduction was used more frequently. In this study, most of the fractures were treated with open reduction because it can prevent some unwanted consequences such as body weight reduction, poor oral hygiene, speech difficulties, and periodontal disease associated with the closed reduction approach. The complication rate in our study was 7.2%, very close to the results of one Brazilian study (Brasileiro and Passeri, 2006), but lower than that data presented by other authors ranging from 11% (Torgersen and Tornes, 1992) to 12.8% (Zachariades et al., 1993). Transient local infections were the major complication type, accounting for 4.7% of all cases and 64.8% of the complications observed. The characteristics of the fracture locations and degree of bone fragmentation also contribute to the development of postoperative complications (Brasileiro and Passeri, 2006). Our study showed that, most of the infections happened either in patients with comminuted mandibular or NOE complex fracture, or who had been admitted to the hospital a significant time after the primary injury. Based on our extensive literature search, this study is the first and largest comprehensive retrospective study of maxillofacial fractures published in the English-language literature from China.
Please cite this article in press as: Mijiti A, et al., Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study, Journal of Cranio-Maxillo-Facial Surgery (2013), http://dx.doi.org/10.1016/j.jcms.2013.05.005
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One of the major limitations in our study is that, although it can be a representative paper for epidemiological characteristics of maxillofacial fractures that occurred in our region; it is hard to determine the overall trend of maxillofacial fractures in China. Like other retrospective studies this analysis may be subject to information bias due to inaccurate original examination, and incomplete records and documentation. However, the results do provide important information necessary for the development and evaluation of preventative measures aimed at reducing the frequency of facial injuries, mainly due to road traffic accidents in China, where the incidence of road traffic accidents is increasing annually, and the majority of severe maxillofacial injuries occur in these motor vehicle crashes. 5. Conclusion The results of our retrospective study revealed the essential epidemiological features of maxillofacial fractures occurring in China between 2006 and 2010. As the first and largest comprehensive study of maxillofacial injuries in our region; it will provide valuable information for government officials and health care providers on the prevention of road traffic accidents, which is characterized the main, and increasing cause of facial injuries, and additional associated injuries. Based on the epidemiological features of maxillofacial injuries in our region, additional studies with larger sample sizes should be conducted, and close attention should be paid to the prevention and treatment of these injuries caused by road traffic accidents in our country. Funding None declared. Disclosure of any previous publications or submissions with any overlapping information None. Competing interests None. References Adebayo ET, Ajike OS, Adekeye EO: Analysis of the pattern of maxillofacial fractures in Kaduna, Nigeria. Br J Oral Maxillofac Surg 41: 396e400, 2003 Al Ahmed HE, Jaber MA, Abu Fanas SH, Karas M: The pattern of maxillofacial fractures in Sharjah, United Arab Emirates: a review of 230 cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 98: 166e170, 2004 Al-Khateeb T, Abdullah FM: Craniomaxillofacial Injuries in the United Arab Emirates: a retrospective study. J Oral Maxillofac Surg 65: 1094e1101, 2007 Ansari MH: Maxillofacial fractures in Hamedan province, Iran: a retrospective study (1987e2001). J Craniomaxillofac Surg 32: 28e34, 2004 Bakardjiev A, Pechalova P: Maxillofacial fractures in Southern Bulgaria e a retrospective study of 1706 cases. J Craniomaxillofac Surg 35: 147e150, 2007
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Please cite this article in press as: Mijiti A, et al., Epidemiological analysis of maxillofacial fractures treated at a university hospital, Xinjiang, China: A 5-year retrospective study, Journal of Cranio-Maxillo-Facial Surgery (2013), http://dx.doi.org/10.1016/j.jcms.2013.05.005