Abstract
Aims
Traumatic injuries remain a major cause of morbidity, mortality and economic loss worldwide. An audit of maxillofacial injuries presenting and managed at any facility is key to understanding the trends, strategies for prevention and improving outcome of care. We sought to study the pattern and treatment of facial bone fractures managed at the Department of Maxillofacial Surgery, Obafemi Awolowo University Teaching Hospital, Ile-Ife, between 2005 and 2013. Also, to compare these with the pattern in the preceding 29 years.
Methods
Data on patients’ socio-demographics, dates of injury and presentation, interval before presentation, agent of injury, type of crash, patient’s status, type(s) of fracture, extent of injury, treatment offered and outcome were collected and analyzed.
Results
311 patients aged 5–72 years were reviewed. A male preponderance was observed. Peak age incidence was 21–30 years and 86.1 % of injuries resulted from road traffic crashes (RTC) most (67.5 %) of which were motorcycle related injuries. 215 patients sustained mandibular fractures in 311 sites while 141 patients sustained 225 midface fractures. Of the 242 patients managed definitively, only 11.2 % had open reduction and internal fixation.
Conclusion
Motorcycle related RTC remains the major cause of facial bone fractures. Management with osteosynthesis is gradually emerging, although demonstrating fewer complications, it is unaffordable for a majority.
Keywords: Facial bone fractures, Trend, Treatment
Introduction
Traumatic injuries constitute a source of considerable economic expense due to procedural costs, disability year lost and the associated income loss [1]. Maxillofacial injuries occur in a significant proportion of trauma patients, consequently, it constitutes an important health and economic issue. The aetiology of maxillofacial injuries varies from one country to another and even within the same country, depending on the prevailing socioeconomic, cultural and environmental factors [2].
Road traffic crash has been reported repeatedly as the leading cause of facial bone fractures in many African countries [3]. Three studies reviewing different time frames in Ile-Ife, Nigeria affirmed this trend [4–6]. Ile-Ife is a southwestern Nigerian town with a population of about 350,000 constituting less than 0.3 % of the national population [7]. Nigeria, Africa’s most populous country, is a developing country with a sizable number of unemployed youths [8]. Apart from serving Ile-Ife, the Obafemi Awolowo University Teaching Hospital (OAUTH) is a referral centre for four neighbouring states. It also lies along a major interstate road trunk connecting the southwestern to the eastern and northern parts of Nigeria.
Over the last decade in most Nigerian cities, motorcycles have replaced automobiles as the major means of intra-city commuting. The change has been attributed to the unsatisfactory and largely un-motorable road networks [9].
Traditionally in Nigeria, most patients with facial bone fractures have been managed conservatively (usually with mandibulomaxillary fixation (MMF)) and on few occasions, with open reduction and internal fixation (rigid/non rigid) [3, 10]. In the past, the few patients who underwent open reduction had their fractures immobilized with transosseous wires. Facilities for osteosynthesis have recently become accessible to maxillofacial surgeons in Nigeria, although at unaffordable costs for a majority of patients. This has resulted into a change in the treatment protocol to accommodate the use of bone plates and screws in fracture fixation [11].
Periodic verification/audit of the etiology of maxillofacial injuries in a particular location helps to formulate and recommend appropriate preventive strategies. Similarly, review of treatments and their outcome enhances improvement in practice [12].
This study sets out to assess the trends in maxillofacial bone fractures presenting at Obafemi Awolowo University Teaching Hospital (OAUTH), Ile-Ife over the period between January 2005 and December 2013. The pattern of facial bone fractures and demography of patients will be compared to the three previous studies and treatment offered as well as outcome will be assessed.
Materials and Methods
A retro-prospective review of the records of all patients seen at the accident and emergency unit and the outpatient clinic of the Department of Oral and Maxillofacial Surgery of OAUTH, Ile-Ife presenting with facial bone fractures was conducted. The review period covered January 2005 to December 2013. Information on patients’ socio-demographics, date of injury, date of presentation, interval before presentation, agent of injury, type of crash, patient’s status, type(s) of fracture, extent of injury, treatment offered and outcome were collected.
Facial bone fractures were diagnosed through a combination of history taking, thorough clinical examination and radiographic imaging (plain radiographs and or CT scan depending on what was accessible and affordable). Location and number of fractures were determined for all patients.
The data generated was entered into a computer. Using the SPSS statistical software package version 22. Simple descriptive statistics and Chi square tests were carried out. Findings in this study were compared with previous results in the centre. Statistical significance was inferred at p < 0.05.
Results
A total of three hundred and eleven cases were available for review over the study period of 9 years. Table 1 displays the distribution of fractures and demographic pattern of patients seen over a period of thirty-seven years. Table 2 illustrates the patients’ distribution by age group and gender in the present and previous studies. The present study demonstrates a sustained significant male preponderance, with two hundred and fifty-three patients being males (M:F = 4.4:1). The patients’ age range was 5–72 years with mean age (SD) at 31 (11.3) years. The peak age incidence was 21–30 years with about 46 % of all patients in this age bracket (Tables 1, 2).
Table 1.
Frequency of fractures and demographic pattern of patients seen over the period of thirty-seven years (1976–2013)
| Variables | Present study | Third study | Second study | First study |
|---|---|---|---|---|
| Period | 2005–2013 | 1996–2004 | 1982–1995 | 1976–1981 |
| Number of years | 9 years | 9 years | 14 years | 6 years |
| Total number of patients | 311 | 451 | 442 | 231 |
| Total number of fractures | 535 | 632 | 517 | 441 |
| Average patients per annum | 34.6 | 50.1 | 31.6 | 38.5 |
| Average fracture per patient | 1.72 | 1.4 | 1.17 | 1.9 |
| Average fracture per year | 59.4 | 70.2 | 36.9 | 73.5 |
| M:F | 4.4:1 | 3.5: 1 | 4.1:1 | 5.4:1 |
| Age range | 5–72 | 1–70 | 1–70 | 1–80 |
| Mean age (SD) | 31.0 (11.3) | 29.1 (13.04) | 30.33 (13.17) | |
| Peak age group | 21–30 | 21–30 | 21–30 | 21–30 |
| Mandible: midface | 1.4:1 | 1.4: 1 | 2.3: 1 | 2.1: 1 |
Table 2.
Distribution of facial bone fracture patients by age groups over the thirty eight years
| Age Group | Male No (%) | Female No (%) | Total No (%) | Oginni et al. (1996–2004) No (%) | Ugboko et al. (1982–1995) No (%) | Odusanya et al. (1976–1981) No (%) |
|---|---|---|---|---|---|---|
| 0–10 | 3 (1.0) | 4 (1.3) | 7 (2.3) | 36 (8 %) | 25 (5.7) | 12 (5.2) |
| 11–20 | 20 (6.4) | 14 (4.5) | 34 (10.9) | 62 (13.7) | 69 (15.6) | 56 (24.2) |
| 21–30 | 122 (39.2) | 22 (7.1) | 144 (46.3) | 179 (39.7) | 173 (39.2) | 85 (36.8) |
| 31–40 | 69 (22.2) | 11 (3.5) | 80 (25.7) | 98 (21.7) | 93 (21.0) | 33 (14.3) |
| 41–50 | 24 (7.7) | 5 (1.6) | 29 (9.3) | 42 (9.3) | 53 (11.9) | 20 (8.7) |
| 51–60 | 9 (2.9) | 1 (0.3) | 10 (3.2) | 24 (5.3) | 22 (5.0) | 12 (5.2) |
| 61–70 | 5 (1.6) | 1 (0.3) | 6 (1.93) | 10 (2.2) | 7 (1.6) | 8 (3.5) |
| >70 | 1 (0.3) | 0 (0.0) | 1 (0.3) | 0 (0.0) | 0 (0.0) | 5 (2.2) |
| Total | 253 (81.4) | 58 (18.6) | 311 (100) | 451 (100) | 442 (100) | 231 (100) |
In addition to thorough clinical examination, 97.1 % of patients were diagnosed based on use of plain radiographs while only 9 cases (2.9 %) were investigated with CT scan images. 86.1 % of all cases of facial bone fractures resulted from road traffic crashes (RTC) with motorcycle related crashes accounting for 67.5 % of all facial bone fractures, whereas 18.6 % of patients were victims of motor vehicular crashes (Fig. 1). Only 3 (1.0 %) patients presented on account of sports related injuries. Most of the victims of motorcycle related crashes were riders in contrast to motor vehicular crashes where more passengers were involved than drivers (p < 0.001) (Table 3).
Fig. 1.
Aetiology of facial bone fractures in the previous and present study
Table 3.
Status of patients involved in road traffic crashes (2005–2013)
| Aetiology | Driver/rider No (%) | Passenger No (%) | Pedestrian No (%) | Total No (%) |
|---|---|---|---|---|
| Motor vehicle crashes | 13 (24.1) | 40 (74.1) | 1 (1.9) | 54 (100) |
| Motorcycle | 129 (64.8) | 66 (33.1) | 4 (2.0) | 199 (100) |
| Total | 142 (56.1) | 106 (41.9) | 5 (2.0) | 253 (100.0) |
| Χ2 = 29.54 df = 2 p = 0.000 | ||||
Most facial bone fractures (60.9 %) were sustained during the second (33.2 %) and first (27.7 %) quarters of the years. The modal month was May (Fig. 2). 73.3 % of the patients presented within the first week of sustaining injuries with over half of them (42.1 %) presenting within 24 h of being injured (Table 4). There was associated altered level of consciousness (Glasgow Coma Scale less than 15) in 134 (43.1 %) patients. Majority of them 108 (80.6 %) however regained consciousness within an hour of sustaining their injuries. We found no significant relationship between patients’ altered level of consciousness and fracture site (i.e. midface or mandible) (p = 0.21) however, the aetiology of injuries appear to affect the level of consciousness (p = 0.001) Table 6.
Fig. 2.
Monthly presentation of facial bone fracture patients
Table 4.
Interval before presentation in the hospital
| Intervals | Present study (2005–2013) | Oginni et al. | Ugboko et al. |
|---|---|---|---|
| <24 h | 55 (31.3) | 170 (37.7) | 138 (31.2) |
| 24 h to 7 days | 74 (42.0) | 207 (45.9) | 231 (52.3) |
| 8 days to 2 weeks | 28 (15.9) | 29 (6.4) | 27 (6.1) |
| >2 weeks to 4 weeks | 8 (4.5) | 24 (5.3) | 22 (5.0) |
| >4 weeks to 4 months | 10 (5.7) | 15 (3.3) | 16 (3.6) |
| > 4 months | 1 (0.6) | 6 (1.3) | 8 (1.8) |
| Total | 176 (100) | 451 (100) | 442 (100) |
| Χ2 = 27.507 df = 5 p = 0.002 | |||
Table 6.
Relationship between levels of consciousness, aetiology and site of injury
| Aetiology | Loss of consciousness | Total | |
|---|---|---|---|
| Yes | No | ||
| Motor vehicle accidents | 21 | 37 | 58 |
| Motor cycle accidents | 106 | 103 | 209 |
| Assault | 3 | 12 | 15 |
| Falls | 4 | 12 | 16 |
| Sports | 0 | 3 | 3 |
| Gunshot | 0 | 8 | 8 |
| 134 | 175 | 309 | |
| p = 0.001 | |||
| Site of fractures | |||
| Mandible | 89 | 125 | 214 |
| Midface | 45 | 50 | 95 |
| 134 | 175 | 309 | |
| p = 0.205 | |||
One hundred and seventy patients sustained mandibular fractures only, 96 sustained middle face fractures only and 45 had a combination of both.
Altogether, 215 patients sustained mandibular fractures in 311 sites. The most frequently fractured region of the mandible was the parasymphyseal region, 100 (32.2 %), followed by the body, 81 (26.0 %). The dentoalveolar region, 19 (6.1 %), was the least affected part of the mandible (Table 5).
Table 5.
Site distribution of facial bone fractures (2005–2013)
| Mandibular fracture sites | Males | Females | No (%) |
|---|---|---|---|
| Condyle | 27 | 8 | 45 (14.5) |
| Angle | 30 | 9 | 40 (12.9) |
| Body | 64 | 7 | 81 (26.0) |
| Parasymphyseal region | 76 | 12 | 100 (32.1) |
| Symphysis | 23 | 3 | 26 (8.4) |
| Dentoalveolar | 14 | 5 | 19 (6.1) |
| Total | 234 | 44 | 311 (100) |
| Zygomatic complex | 90 | 18 | 108 (48.0) |
| Le Fort I | 17 | 4 | 21 (9.3) |
| Le Fort II | 36 | 10 | 46 (20.4) |
| Le Fort III | 13 | 4 | 17 (7.6) |
| Nasal | 11 | 4 | 15 (6.7) |
| Palatal | 15 | 3 | 18 (8.0) |
| Total | 182 | 43 | 225 (100) |
The midface fractures affected multiple sites more than the mandible as 141 (45.3 %) patients sustained fractures at 225 midfacial sites. Zygomatic complex fracture was present in 108 (34.7 %) patients, but isolated nasal fractures were seen only in 15 (4.8 %) patients. Le Fort II fracture was the commonest (14.8 %) of the Le Fort type fractures.
In the midface, close to half (48 %) of fracture sites were located in the zygomatic complex. Le Fort type fractures (I, II and III) constituted 37.3 %, palatal split 8 % and isolated nasal bone fractures 6.7 % (Table 5).
Two hundred and forty-two (77.8 %) of the patients received definitive treatment. Most of them (88.8 %) were treated conservatively, predominantly with MMF, while only 27 (11.2 %) of them had open reduction and internal fixation (ORIF). Eighty-nine complications were reported in all, majority (88/89) of which were associated with MMF. The commonest complication observed was trismus (Fig. 3). The only complication associated with ORIF was a single case of unsightly scar (1/89).
Fig. 3.
Complications of cases managed
Discussion
Cultural, socioeconomic, environmental and geographical factors greatly influence the pattern of maxillofacial fractures worldwide; being determinants of the subsection of a population that is most predisposed, the aetiologies, and severity of injuries sustained [3, 13]..
The average number of patients per year recorded in this study represents a 31 % drop from the report of the preceding 9 years. This average is however similar to the reports of Ugboko et al. [6] and Odusanya [4] (Table 1) recorded when the population of Osun state was much lower and there were fewer treatment centers in the South western zone.
Thus, we may attribute the drop to establishment of three new maxillofacial centres in neighbouring states. Also, we opine that the mobile telecommunication device revolution may have reduced the need for unnecessary long distance journeys considerably. Transportation among Nigerians is highly connected to communication. Before the year 2001, Nigerian telecommunication system was grossly inefficient; consequently, there were many reasons to travel. Mobile phones were however introduced in 2001; and have gradually penetrated the population to steadily attain a teledensity of 91.15 % in December 2013 [14]. This no doubt, has vastly enhanced communication and modified travel pattern.
There was a steady drop in the male to female ratio over the years from 1976 to 2004 as more females took up outdoor activities. Many studies in Nigeria have also reported a similar trend [3]. The current study however shows a rise in the proportion of males involved in maxillofacial trauma relative to females (4.4:1) across all age groups with the exception of the first decade of life. We attribute this to the exclusive male dominance, of the motorcycle riders who constituted about 40 % of all patients [15].
The age group most susceptible to maxillofacial fractures remains the third decade of life as widely reported [3]. In this study, about 83 % of patients were in the 2nd to 4th decades of life. This age bracket represents the most productive in any population. Only 2.25 % of patients seen were children under 10 years, which is a 72 % drop in proportion of children observed by Oginni et al. [5].
Between 2000 and 2009, youth unemployment rate was put at 58.6 % among citizens aged 15–44 years [16, 17]. Statistics from the Manpower Board and National Bureau of Statistics reveal that Nigeria has a youth population of 80 million (representing about 60 % of the National population) and 64 million are unemployed while 1.6 million are underemployed [18, 19]. Furthermore, massive youth unemployment rate in Nigeria has been attributed to corruption, decline in the manufacturing sector, rapid population growth and rural urban migration among others [8]. Majority of unemployed youths engage in vocations like street trading/hawking, commercial motorcycling, porters, motor-park boys, etc. which predispose them to RTCs [20].
RTCs are still responsible for most maxillofacial trauma presenting at our facility. This pattern is also reported in most Nigerian studies as well as a large number of developing countries [3]. Reasons alluded for these include bad road networks, poor evaluation of roadworthiness of vehicles and non-enforcement of road traffic rules and regulations [20]. However, this study demonstrates a very high proportion of trauma being related to motorcycle crashes alone (68.2 %) which is a cause for concern.
Additionally, motorcycle has become a major means of intra-city commuting in Nigeria [15]. Its popularity is attributable to ease of navigating through bad road networks and the attendant traffic jam associated with movement delays in towns. In addition, the high unemployment rate makes commercial motorcycling an attractive prospect for the young and unemployed. Commercial motorcycle riders are usually young men who are often not well educated and are adventurous. A lot of them are unlicensed, wear no protective helmet and often ride under the influence of intoxicants [15].
Motorcycle riders were more predisposed to sustaining facial bone fractures than their passengers. The reverse was observed for victims of motor vehicular crashes. We opine that a fair level of compliance with the seat belt use regulation by motor vehicle drivers and front seat occupants only may be responsible for this [21]. Rear seat passengers tend to go unrestrained and hence sustain more injuries during crashes. Unfortunately, riders rarely wear crash helmets with a protective visor or strapping if any at all [15]. The rise in proportion of RTC victims has overshadowed the proportions due to other causes like assault, falls, and sports which now contribute to even smaller fractions than previously recorded.
Delay in presentation featured quite prominently in the present study with statistically significant fewer patients (p = 0.002) presenting for treatment within the first week of injury compared to two of the previous studies. It is important to note that our referral protocol engages the maxillofacial unit and all other managing units (depending on the presence of concomitant injury or injuries) at presentation. Delays however are often informed by the typical economic constraint experienced by commercial motorcyclist who would usually seek alternative cheaper treatment first. Also, some relative delay in presentation may be attributed to delayed referral from primary managing facilities that are unequipped for maxillofacial care delivery. In this series, 43 % of patients had loss of consciousness and 8.4 % were still unconscious after 24 h. While GCS scores may be a predictor of the severity of injuries, our findings suggest that MC related crashes are most likely to result in loss of consciousness (Table 6).
In consonance with popular reports of maxillofacial fractures, mandible was the facial bone most susceptible to fracture in this series [1, 3, 22]. Its prominence and mobility have been adduced as the reason for this predisposition. Likewise among the midface fractures, zygomatic complex fracture was the most common. The ratio of mandibular to midface fractures recorded is similar to Oginni et al’s. [5] study and represents a relative reduction to the proportion of mandibular fractures reported between 1976 and 1995.
This study like many Nigerian studies found the mandible to be most susceptible to fracture in the parasymphyseal/body region. Odusanya however reported more condylar fractures [3] with predominant motor vehicle crashes. This is a puzzle that needs to be unravelled. Plausible explanations are the possibility of missed diagnosis, especially with the predominant parasymphyseal fractures in the current series. Possibly the force transferred in motorcycle related crashes was not sufficient to cause condylar fractures.
Many studies of the bio mechanism of MC related versus vehicle passenger crashes provide overwhelming evidences in support of the motor vehicle occupant’s greater relative protection than the MC rider or passenger [23]. The use of seat belts and presence of air bags in cars as opposed to lack of restraints or support for the rider and pillion passenger may further help to highlight these differences.
Since radiographic assessment was done mostly with the aid of plain radiographs, this may account for a degree of under-reporting of fractures that could have been detected easily on CT scan images. Although more diagnostic centers with CT scan services are opening up in our neighborhood, affordability remains a challenge to majority of patients.
Although maxillofacial fractures occurred all year round, a peak was observed in May (a rainy month in the southwest of Nigeria) and a low recorded in August. The trough observed in August also corresponds to the August break in rainfall. We opine that wet slippery roads and paths contribute to more motorcycle related crashes in the peak period as presented in other studies [4–6, 24]. Proposed special precautions include avoidance of MC riding in the rain/special speed limit on rainy days.
The choice of treatment option was made based on patient’s financial capability, availability of materials and kit for rigid fixation, severity of facial bone fracture and availability of theatre space. As such open reduction and rigid internal fixation was seldom employed. However with the availability of a kit for osteosynthesis, the few cases of ORIF done recently, yielded promising results. The pattern of complications recorded reflect the preponderance of MMF related complications (Fig. 3). Although ORIF is more expensive and invasive, compared with MMF, the low complication and co-morbidity rates are reasons for its use. The only ORIF related complication in this series (unsightly scar); may be termed avoidable. We believe that avoidance of extra-oral incision (more so in the black population) is attainable if a full complement of appropriate instruments are available.
Conclusion
Although the overall pattern of maxillofacial fractures has remained the same in the last few years, the strong emergence of motorcycle as a major means of commuting appears to have tilted the pattern back towards young and exuberant males. Serious and concerted effort at enforcement of road traffic regulations as well as infrastructural development has a potential to reduce road traffic crashes. Restrictions on commercial motorcycling and accommodation of riders in other transport services will also be beneficial in limiting facial fractures. Although osteosynthesis is not very popular yet in our practice, the outcome of its use suggests that its use has the prospect of reducing morbidity associated with management of maxillofacial fractures using the conventional techniques.
Acknowledgments
We are grateful to all patients and colleagues who participated in the care of the patients at every point in time.
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