|Year : 2012 | Volume
| Issue : 3 | Page : 131-138
Computerized tomography assessment of cranial and mid-facial fractures in patients following road traffic accident in South-West Nigeria
Adeyinka Abiodun1, Agunloye Atinuke1, Osuagwu Yvonne2
1 Department of Radiology, University College Hospital, Ibadan, Nigeria
2 Department of Radiology, Wuse General Hospital, Abuja, Nigeria
|Date of Web Publication||5-Jun-2012|
Department of Radiology, University College Hospital, Ibadan
| Abstract|| |
Background: Globally, the most common cause of cranio-facial fractures is road traffic accident (RTA) with computerized tomography (CT) scan as the gold standard in the diagnosis of patients with cranial and facial fractures. The purpose of this study is to assess the pattern of cranial and facial fractures on CT in head injured patients following RTA.
Materials and Methods: Using CT, detailed analyses of 236 patients with head injury following RTA were performed between 2006 and 2008, Data recorded included cause of injury, age and gender distribution, cranial and mid-facial fractures sustained, associated intracranial and soft tissue injury and the types of vehicular accident.
Results: The peak age of the patients was between 30 and 39 years. RTA was more common in males than females. Motor-vehicle was the most common cause of RTA in the present study (66.9%). More passengers were involved in the motor vehicle (87.3%) and motorcycle (52.0%) accidents than their corresponding drivers, and they were predominantly males. Majority of the patients involved in pedestrian road traffic accident (PRTA) were motor vehicle victims (93.3%). There were more patients with cranial (59.8%) than mid-facial fractures (40.2%). Majority of the patients had temporal bone cranial fracture (31.1%) and combined or mixed type of mid-facial fractures (41.3%). Intracranial bleeding (31.7%) was the most common associated intracranial finding.
Conclusion: RTAs continue to be a menace and are the main cause of craniofacial injury in Nigeria. This pattern of etiologic factors is in accordance with data from most developing countries. Special attention should be paid to reinforcement of legislation and enactment of laws aimed at the reduction of head injury and provision for easy access to CT for the head injured patient.
| Abstract in French|| |
Contexte: à l'échelle mondiale, la cause la plus fréquente des fractures cranio-facial est accident de la route (RTA) avec la tomographie par ordinateur (CT) analyse comme l'étalon-or dans le diagnostic des patients atteints de fractures crâniennes et du visage. Le but de cette étude est d'évaluer le profil des fractures crâniennes et faciales sur CT en têtes blessés suite RTA.
Des matériaux et des procédés: Using CT, des analyses détaillées de 236 patients avec traumatisme crânien suite RTAentre 2006 et 2008, les données enregistrées inclus cause de blessure, âge et sexe distribution, crânienne et fractures mid-facial subies, associé de la lésion tissulaire intracrânienne et mous et les types d'accident automobile.
Résultats: Le pic de l'âge des patients a été entre 30 et 39 ans. RTA était plus fréquent chez les hommes que chez les femelles. Véhicule à moteur est la cause la plus fréquente de LLUH dans la présente étude (66,9%). Plus de passagers étaient impliqués dans les véhicules automobiles (87,3%) et les accidents de moto (52,0%) que les conducteurs de leurs correspondants, et ils étaient surtout les hommes. La majorité des patients impliqués dans un accident de la circulation routière pour piétons (pâturages) ont été victimes de véhicules automobiles (93,3%). Il n'y a plus de patients avec crânienne (59,8%) que les fractures mid-facial (40,2%). La majorité des patients avait fracture du crâne os temporal (31,1%) et type combiné ou mixte de fractures mid-facial (41,3%). Intracrânienne Hémorragie (31,7%) a été le plus souvent associés conclusion intracrânienne.
Conclusion: RTAs continuent d'être une menace et sont la principale cause de blessures craniofaciales au Nigeria. Ce patron de facteurs étiologiques est conforme aux données de la plupart des pays en développement. Devrait être une attention particulière au renforcement de la législation et de la promulgation de lois visant à la réduction de la blessure à la tête et de disposition pour un accès facile au CT pour le patient blessés tête.
Mots clés: Calculée tomography, craniofacial, intracrânienne, moto, piéton
Keywords: Computed tomography, craniofacial, intracranial, motorcycle, pedestrian
|How to cite this article:|
Abiodun A, Atinuke A, Yvonne O. Computerized tomography assessment of cranial and mid-facial fractures in patients following road traffic accident in South-West Nigeria. Ann Afr Med 2012;11:131-8
|How to cite this URL:|
Abiodun A, Atinuke A, Yvonne O. Computerized tomography assessment of cranial and mid-facial fractures in patients following road traffic accident in South-West Nigeria. Ann Afr Med [serial online] 2012 [cited 2013 May 24];11:131-8. Available from: http://www.annalsafrmed.org/text.asp?2012/11/3/131/96860
| Introduction|| |
In Nigeria, Road Traffic Accident (RTA) is the most common cause of cranial and facial injuries.  Motor vehicle followed by Motorcycle road traffic accidents are the prevalent mode of transportation resulting in head injury in road traffic accident amongst Nigerians. [2,3] Pedestrian road traffic accident involvement is more common in children,  Malara et al, in Poland documented motor vehicle RTA as the most frequent cause of facial fractures. In South Africa van As et al recorded a higher incidence of car related facial injuries amongst children even though most victims were pedestrians. About one third to half of all victims of cycling accidents in developing countries sustain some degree of trauma to the head and face.  Furthermore, in crashes between motorcycles and cars, the motorcyclist and his passengers are more prone to injury than the motor vehicle occupants. 
In Nigeria, the prevailing economic circumstances have led to an upsurge in the use of motorcycles for private and commercial purposes and their popularity has also been attributed to their ability to circumvent the poor road networks, traffic jams and narrow roads in the country. , This has led to a steady increase in the number of motorcycle related maxillofacial injuries. Between 1995 and 1999, Fasola et al noted a doubling in the incidence of motorcycle related injuries. A comprehensive review of literature carried out by Adeyemo et al showed significant increase in motorcycle-related injuries over the last 40 years. Patients involved in motorcycle related RTA (MCRTA) are at high risk for head injury with about one third to half of all victims of cycling accidents in developing countries sustaining some degree of cranial and facial injuries.  Cranial fractures which may involve either the frontal, parietal, Temporal and occipital bones, are often accompanied with intracranial injuries. Lloyd et al also reported cases of Intracranial injuries associated with skull fractures in head injured children evaluated on CT scan. The orbit, frontal bone and maxilla are the most commonly fractured facial bones in South African children.  When taken together, fractures of the orbit, zygomaticomaxillary and sinonasal complexes formed the majority of facial fractures recorded by Malara et al and
Gassner et al.  Fractures of the nasal bone are also common  while fractures of the zygomaticofrontal suture are the most frequent in motorcycle related trauma 
Computerized Tomography is the investigation of choice in head trauma imaging. MRI has excellent soft tissue contrast and is complementary to CT for additional evidence of trauma such as soft tissue and brain injury, , but it has limited usefulness in bone imaging. ,,, Plain Skull radiographs is another imaging option for the head injured patient, but fractures are missed or incompletely shown at radiography, especially in uncooperative trauma victims 
The aim of this study is to assess the pattern of cranial and mid-facial fractures in Road Traffic Accidents according to road user categories.
The severity of head injuries related to RTA and the availability of Computerized Tomography in our centre has made it a point of focus to carry out this study.
| Materials and Methods|| |
A prospective evaluation of Cranial Computerized Tomography scan of 236 patients referred to the Radiology Department of the University College Hospital, Ibadan, Nigeria, with head injury following Road Traffic Accident over a 2 year period from January 2006 to June 2008 was performed.
Ethical approval was obtained from the institutions ethics review committee. Informed consent to participate in the study was obtained from all conscious adult patients, while consent was obtained from parents or guardians in unconscious patients or minors (less than 18 years).
Cranial and facial fractures from any causes other than RTA were excluded from the study. Only acute head injuries were included in the study with an upper limit of seven days.
All CT Images were obtained using a helical technique with a General Electric (GE CT/e) single detector scanner (General Electric medical systems). The scanning parameters for un-enhanced CT were 120KV minimum tube current 512 × 512 matrix and 15cm field of view. Scan duration was about 5-10 minutes in all cases. Scans were taken from the posterior margin of the first cervical vertebral body and extended up to the vertex, with a 3mm section thickness through the base of skull and 7mm up to the vertex. To obtain maximal imaging acquisition, examination was tailored to specific clinical indications in order to clearly demonstrate the fractures. Axial non-contrast images were acquired in all patients while Coronal images were acquired where necessary. Only non-contrast images were acquired in order not to mask any features of acute trauma. The acquisition volume for the axial images was angled parallel to the superior orbitomeatal line to avoid irradiating the orbits. Coronal images were taken with the patient in a prone position and images are acquired in the anterior-posterior direction. .
Morphologic evaluation of the images was performed in consensus by two experienced radiologists. All images were reviewed in Bone and Brain windows. Comprehensive personal data regarding age, sex, type and circumstances of injury were obtained. The fracture pattern was documented in the data collection form after a detailed review of CT findings.
The presence or absence of cranial and mid-facial fractures on Computed Tomography, anatomical sites, Non-osseous findings and the etiology of the RTA were noted.
The Aetiology of RTA was divided into 3 groups according to Road User categories.
These are as follows:
MVRTA - Road users involve in Motor Vehicle RTA
MCRTA - Road users involve in Motorcycle RTA
PRTA - Road users knocked down by a Motor vehicle or Motorcycle'
The Fracture Types were divided as follows:
Cranial: Fractures involving the a) Frontal, b) Temporal, c) Parietal and d) Occipital bones
Mid-Facial: Fractures involving the facial skeleton were categorized into:
a) Sino-nasal, b) Zygomatico-maxillary, c) Orbital fractures and d) Mixed (more than one fracture sites) fractures
The data obtained was analyzed using the statistical package for social sciences (SPSS 15.0 Inc. Chicago, Illinois).correlations was obtained with chi-squared tests with 95% confidence interval. Mean values, distribution of variables are represented on tables and Pie charts where appropriate.
| Results|| |
A total of 236 patients who sustained cranial and mid-facial fractures following road traffic accident (RTA) were evaluated with Computed Tomography.
[Table 1] shows the Age-Sex frequency distribution pattern of the subjects. 73.7% were males while 26.3% were females, with a male: female ratio of 3:1. The age range was 2-73yrs, with overall mean age of 29yrs±17.51. The mean age for the males was 28.5yrs±16.3 while that of females was 30.8yrs±19.29 P = Majority of the patients were found in the 3 rd , 4 th and 5 th decade 64.4%, with the hihest frequency of males in the 4 th decade 29.3% while the highest frequency of females were in the 3 rd and 5 th decades 21%.
|Table 1: Age-sex frequency distribution pattern of head injured patients|
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[Table 2] is the Age-Sex distribution pattern of the head injured patients in RTA in their respective Road User categories. Motor Vehicle (MVRTA) was the commonest cause of road traffic accident in the present study 66.9% (P =0.026), followed by Motorcycle (MCRTA) 20.4% and Pedestrian (PRTA) 12.7%. The patients were predominantly males in both the MVRTA 75.3% and the MCRTA 83.3%, but with equal sex distribution in the PRTA. Majority of the motor vehicle injured patients were in the 4 th decade 31.7%, while the motorcycle and pedestrian patients were in younger age group of 3 rd (45.8%) and 2 nd (33.3%) decades respectively.
|Table 2: Road User and Age-Sex Distribution Pattern of head injured road traffic accident patients|
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[Table 3] shows the Patient's position and Sex distribution pattern in all the Road User categories.
|Table 3: Patients site-sex distribution pattern in respective road user categories|
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More passengers were involved in the motor vehicle 87.3% and motorcycle 52.0% accidents than their corresponding drivers, and they were predominantly males. There was statistically significant higher male passengers and drivers in the motor vehicle 71.7% (P = 0.006) and motorcycle 68.0% (P = 0.003) accidents, with no female driver recorded in either the motor vehicle or motorcycle accidents. There were more motor vehicle victims 93.3% than the Motorcycle victims 6.7% in the Pedestrian road traffic accidents, and with predominantly female victims 53.6% (P= 0.059), but not statistically significant.
Out of the 236 road traffic accident patients that were evaluated by Cranial CT scan, abnormal findings were recorded in 84.3% patients while 15.7% show normal findings [Figure 1].
|Figure 1: Percentage distribution pattern of normal and abnormal computerized tomography findings in the study population|
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[Table 4]a and b shows the distribution pattern of Cranial and Mid-facial fractures according to fracture sites in the different road user categories.
There were more patients with cranial 59.8% than mid-facial fractures 40.2%. The incidence of cranial 68.9% and mid-facial 67.5% fractures was higher in the motor vehicle accidents. In all the cranial fractures [Figure 2], the Temporal bone was the commonest fracture site 31.1%, while the Occipital bone is the least frequent fracture site 10.3%. The Frontal bone is the most frequently involved fracture site in the motor vehicle accident 75.8%, while the Temporal bone was the commonest site for fractures in the motorcycle 21.6% and Pedestrian 13.5% accidents. The commonest type of mid-facial fracture was the Mixed type 41.3%, followed by the Sino-nasal type 35.0% [Figure 3]. The Zygomatico-maxillary types of fractures were more frequently involved in the motor vehicle accidents 75.0%, while Sino-nasal fractures were more frequent in the motorcycle 21.4% and pedestrian 25.0% accidents.
|Figure 2: Axial computerized tomography bone window image showing multiple cranial bone fractures involving the frontal and both parietal bones. The right parietal bone is displaced (arrow)|
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|Figure 3: Axial computerized tomography image (bone window) of mid-facial fracture showing fractures of the lateral and medial walls of the right orbit as well as the inner and outer walls of the left frontal sinus. The left orbit is also fractured|
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[Table 5] shows the distribution pattern of the Non-osseous findings that are associated with the cranial and mid-facial fractures on Computed Tomography in the three categories of Road Users. Majority of the patients with non-osseous findings were in the motor vehicle accident road user category 63.6%. Intracranial bleed 31.7% was the commonest non-osseous findings [Figure 4], followed by Soft Tissue Swelling 22.1% and then Paranasal hematoma 20.1%.
|Figure 4: Non-enhanced computerized tomography (brain window) showing a left hyperdense acute subdural haematoma (arrow). Associated cerebral hematoma is noted in the left parietal lobe. Soft tissue swelling is also present over both parietal bones|
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| Discussion|| |
Road traffic accidents (RTA) lead to high morbidity and mortality in developing countries such as Africa, Latin America and Asia when compared to their counterparts in the developed world  The type of vehicle involved in RTA and thus the etiology of fractures sustained depends on the mode of transportation prevalent in the country in question. This in turn is dependent on the socioeconomic and cultural factors prevailing at the time of study.  Findings from other studies on head injury, have shown that RTA is the commonest cause of head injury, and overall, the most common cause of facial fractures globally.  The upsurge of Motorcycle related accidents has been increasing in Nigeria over the last 40 years,  and this has also been the case in other less developed part of the world  Some authors postulate this to be the result of low income status , and the ability of the motorcycles to circumvent poor road networks. 
Rajendra et al studied the characteristics of craniofacial trauma in patients with head injury and reported that majority of the patients were in the 2 nd - 4 th decade. Our study reported that motor vehicle road traffic accidents (MVRTA) and motor cycle road traffic accident (MCRTA) are most common in patients in 3 rd - 4 th decade of life. The higher incidence in this age group may reflect the inexperience of our youth, or recklessness amongst young motor vehicle drivers and motorcyclists who are sometimes seen to compete when driving on the road.
Previous authors have reported that males are most commonly involved in RTA. ,, This is similar to the predominantly young male population found in our study. Fasola et al studied the trend of maxillofacial injuries and related the recent tendency of equal male: female injury ratio to an increasing percentage of women in the workforce. It is interesting to note that no female driver was recorded in our study for motor vehicle and motorcycle related accidents, and this is likely due to cultural factors particularly in the riding of motorcycles. However, the low incidence of females in our study, especially in MCRTA, may be unique to Nigeria and perhaps other African countries, as anecdotal evidence suggests that it is frowned upon for women to ride motorcycles, and in fact female passengers on motorcycles are discouraged. Fallout of this is that no female motorcyclist driver was recorded.
The pattern, incidence and severity of RTA vary according to the vehicle or mode of transportation prevalent in the region in which the study was conducted. About one third to half of all victims of cycling accidents in developing countries sustain some degree of trauma to the head and face.  Furthermore, in crashes between motorcycles and cars, the motorcyclist and his passengers are more prone to injury than the motor vehicle occupants.  In Japan, Iida and Matsuya  found bicycle related accidents to be more common amongst children while motorcycle related injuries were most frequent in the adult population. In South Africa van As et al recorded a higher incidence of car related facial injuries amongst children even though most victims were pedestrians. It is believed that high incidence of motorcycle related injuries is confined to the developing world as people in more developed nations mainly use cars as a result of increased wealth of the populace.  This observation is supported by Van Beek and Merrkx  who recorded a decrease in motorcycle related facial injury following improved socioeconomic conditions. In evaluating the relationship of position of the patient in the vehicle involved in RTA to the type of fracture in this study, all fracture groups showed higher incidence in motor vehicle and motorcycle passengers. However, this was not statistically significant, thus implying an almost equal risk to drivers and passengers in this environment. This is in contrast to the work of Haug et al who showed that the position of the patient in the vehicle determined severity of injury. The findings in this study may be related to the non-compliance with safety regulations vis a vis helmets for motorcyclists and their passengers and seat belt use for motor vehicle occupants.
In a comprehensive study on craniofacial trauma by Hussein et al,  they reported cranial fractures to be the commonest fracture, and frontal bone was the most commonly fractured cranial bone while the occipital bone is rarely fractured. This is also in agreement with the work of Haug et al. Our study recorded more cranial than mid-facial fractures, but temporal bone was found to be the commonest cranial bone involved. The rarity of occipital fractures may be related to its thickness as well as tendency for falling forward in road traffic injuries. Parietal and frontal fractures were however most commonly seen by Obajimi et al in a similar study. When cranial fractures coexist with facial fractures the frontal/sinonasal combination was most frequent followed by the temporal/sinonasal complex combination. The prevalence of frontal/sinonasal association may be due to the fact that fractures involving the frontal bone may extend into the frontal sinus. Orbital fractures were also commonly seen in association with frontal and temporal bone fractures, while Zygomaticomaxillary fractures were mostly associated with fractures of the temporal bone. These associations have been postulated to be due to continuity of the facial and associated cranial bones via sutural attachments.  This study recorded a high frequency of Mixed or combined mid-facial fracture.
Computed Tomography imaging (CT) studies tends to give more accurate information to the bony architecture of the cranium and mid-facial region. It gives detailed information on the disruption caused by cranio-facial injury. CT imaging is therefore an integral component of the diagnosis of mid-facial and cranial fractures. The most commonly recorded intracranial finding in this study was intracranial hematoma, and this is in keeping with the work of Obajimi et al Akang et al noted that subdural, subarachnoid, extradural and intracerebral haemorrhages were a major cause of death in patients with severe head trauma implying a high severity of the craniofacial injuries recorded in this study.
| Conclusion|| |
The severity of injuries related to motor vehicle and motorcycle road traffic accident has made it a point of focus in studies on RTA in Nigeria. ,,, Poor or lack of compliance with the use of seat belts and helmet have also been recorded by previous authors in Nigeria , and internationall. ,, Thus, in Nigeria with the ever increasing use of motor vehicles and motorcycles as a means of transportation, and the consequent road traffic injuries, there is a need to enforce the universal seat belts and helmet laws and monitor the effect of compliance. The availability of such data from this study and other studies will go a long way to encourage compliance by end-users; as the motorist, cyclist and their passengers will insist on protection when the advantage is eminent.
| References|| |
|1.||Adeyemo WR, Ladeinde AL, Ogunlewe MO and James O. Trends and characteristics of oral and maxillofacial injuries in Nigeria: a review of literature. Head & Face Medicine 2005; 1:7.doi:10.1186/1746-160x-1-7 |
|2.||Rowe LD, Miller E and Brandt - Zawadzki M. Computed Tomography in maxillofacial trauma. Laryngoscope 1981; 91: 745-57. |
|3.||Fasola AO, Nyako EA, Obiechina AE and Arotiba JT. Trends in the characteristics of maxillofacial fractures in Nigeria. J Oral Maxillofac Surg 2003 Oct; 61(10): 1140-43. |
|4.||Shokunbi T and Olurin O. Childhood head injury in Ibadan: causes, neurologic complications and outcomes. West Afr J Med 1994 Jan-Mar; 13(1):38-42. |
|5.||Malara P, Malara B and Drugacz J. Characteristics of maxillofacial injuries resulting from road traffic accidents - a 5year review of the case records from department of maxillofacial surgery in Katowice, Poland. Head & face Med 2006, 2: 27. |
|6.||van As AB, van Loghem AJ, Biermans BFJ, Douglas TS, Wieselthaler N and Naidoo S. Causes and distribution of facial fractures in a group of South African Children and the value of Computed tomography in their assessment Int J Oral Maxillofac Surg 2006; 35 (10): 903-6. |
|7.||Cooter RD and David DJ. Computer based coding of fractures in the craniofacial region. Br J Plast Surg 1989; 42: 17-26. |
|8.||Sangowawa AO, Owoaje ET, Adebiyi AO, Ekanem SE, Faseru B and Adekunle BJ. Patterns of injury from commercial motorcycle crashes in Oyo State, Nigeria. DOKITA 2007; 32 (1): 72-5. |
|9.||Oginni FO, Ugboko VI, Ogundipe O and Adegbehingbe BO. Motorcycle related maxillofacial injuries among Nigerian intracity users. J Oral Maxillofac Surg 2006; 64 (1): 56-62. |
|10.||Lloyd DA, Carty H, Patterson M et al. Predictive value of skull radiography for intracranial injury in children with blunt head injury. Lancet. 1997; 349 (9055):821-4. |
|11.||Gassner R, Tuli T, Hachi O, Moreira R, Ulmer H.Craniomaxillofacial trauma in children. A review of 3,385 cases with 6,060 injuries in 10 years. J Oral Maxillofac Surg 2004;62:399-407. |
|12.||Obajimi MO, Jumah KB, Brakohiapa WO and Iddirisu M Head Injury in Ghanaians, Evaluation by computed tomography. Ghana Med J 2001; 35 (2): 69-74 |
|13.||Salvolini U. Traumatic injuries: imaging of facial injuries. Eur Radiol. 2002 Jun;12(6):1253-61 |
|14.||Foerster BR, Petrou M, Lin D, Thurnher MM, Carlson MD, Strouse PJ, and Sundgren PC . Neuroimaging Evaluation of Non-accidental Head Trauma with Correlation to Clinical Outcomes: A Review of 57 Cases. J Pediatr. 2008 Nov 22. [Epub ahead of print]. |
|15.||Bontrager KL and Lampingnano JP. In Textbook of Radiographic positioning and related anatomy. St Louis, Missouri. Elsevier Mosby 2005 pp 401-443. |
|16.||Kleinheinz J, Stamm T, Meier N, Wiesmann HP, Joos U. MRI 3D imaging of the orbits in craniofacial abnormalities and injuries . Mund Kiefer Gesichtschir. 1998 May;2 Suppl 1:S91-93 |
|17.||Peden, McGee and Krug E. (Eds) world Report on Road Traffic Injury in Geneva. Worl Health Organisation, 2004 |
|18.||Elesha SO and Daramola AO. Fatal head injuries: the Lagos University Teaching Hospital experience (1993-1997). Niger Postgrad Med J.2002 Mar;9(1):38-42 |
|19.||Van Beek GJ, Merkx CA. Changes in the pattern of fractures of the maxillofacial Skeleton. Int J Oral Maxillofac Surg 1999;28:424-8. |
|20.||Rajendra PB, Mathew TP, Agrawall Aand Sabharawal G. Characteristic of associated craniofacial trauma in patients with head injury: An experience with 100 cases. J Emerg Trauma Shock. 2009 May-Aug; 2(2): 89-94 |
|21.||Gentry LR, Manor WF, Turski PA and Strother CM. High resolution CT analysis of facial strict in trauma: Osseous and soft tissue complications. Am J Radiology 1983; 140:533-41 |
|22.||Novelline RA, Rhea JT, Rao PM and Stuk JL. Helical CT in Emengency radiology. Radiology 1999; 213: 321-39. |
|23.||Fasola AO and Denloye OO. Bankole OO Oro-facial soft tissue injuries in Nigerian children: a five-year review. Afr J Med Med Sci.2004 Jun; 33(2):93-7. |
|24.||Iida S and Matsuya T. Paediatric maxillofacial fractures their aetiological characters and fracture patterns. J Craniomaxillofac Surg 2002; 30: 237-41. |
|25.||Haug RH. Adams JM, Conforti PJ and Likavec MJ. Cranial fractures associated with facial fractures: a review of mechanism, type and severity of injury. J Oral Maxillofac Surg 1994; 52: 729-33. |
|26.||Hussain K, Wijetunge DB, Grubnic S and Jackson IT. A comprehensive analysis of craniofacial trauma. J Trauma 1994 Jan; 36 (1) 34-47. |
|27.||Turvey TA. Midface fractures: A retrospective analysis of 593 cases. J Oral Surg. 1977; 35: 887-91. |
|28.||Akang EE, Kuti MA, Osunkoya AO, Komolafe EO, Malomo AO, Shokunbi MT and Amutta SB. Pattern of fatal head injuries in Ibadan - a 10 year review. Med Sci Law. 2002 Apr 42 (2): 160-6. |
|29.||Falope IA. Motorcycle Accidents in Nigeria. A New group at risk. West Afr. J. Med 1991 Apr-Jun; 10 (2):187-9 |
|30.||Cummings P, Rivara FP, Olson CM and Smith KM. changes in traffic crash mortality rates attributed to the use of alcohol, or lack of a seat belt, air bag, motorcycle helmet, or bicycle helmet, United States, 1982-2001. Inj prev. 2006. June; (1293): 148-154 |
|31.||Pomerantz WJ, Gittelman MA and Smith GA. No Licence required: severe pediatric motorbike-related injuries in Ohio. Pediatrics 2005. Mar; 115 (3): 704-9 |
|32.||Brandt MM, Ahrns KS, Corpron CA, Franklin JA. Hospital cost is reduced by motorcycle helmet use. J Trauma 2002;53: 469-71. |
[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]