Closed Reduction of an Isolated Zygomatic Arch Fracture Under Local Anesthesia: A Case Report.

The zygomatic bone is one of the most prominent bones in the facial region. It forms the most anterolateral projection on each side of the middle face and is articulated with the maxilla, frontal, and temporal bones. Isolated zygomatic arch fractures can occur when a direct force is applied to the zygoma. A variety of intraoral and extraoral techniques have been used as closed reduction techniques for isolated fractures of the zygomatic arch. In this case report, we aim to present our approach for the treatment of a 40-year-old patient with an isolated right zygomatic arch fracture. We used the Keen technique for the closed reduction of the fracture under local anesthesia due to its practicality and effectiveness.

Evaluation of the Relationship Between Zygomatic Arch Fracture Reduction and Mandibular Movements.

Objective: The aim of this study was to evaluate the relationship between surgical zygomatic arch fracture reduction and mandibular movements in different fracture types. Materials and Methods: Fractures were classified according to the Yamamoto classification. The extent of zygomatic arch reduction after surgery was evaluated by measuring three reference points on both fractured and normal side both before and after surgery. The selected reference points were: the most anterior (A1), the most posterior (B1) and the midpoint (C1) relative to midsagittal plane on the fracture side and the same points on the normal side (a1, b1, c1). Mouth opening, movements to right and left were recorded in these patients. Results: The highest extent of zygomatic arch reduction was observed at the midpoint of the arch (p = 0.041). Surgery did not significantly alter other points of the zygomatic arch. The extent of reduction of the zygomatic arch was not significantly associated with mandibular movements. However, type of fracture correlated with lateral excursion to the right and left (p = 0.002 and p = 0.031, respectively). Conclusion: This study showed that the amount of post-surgical changes in zygomatic arch reduction was not significantly related to mandibular movements. In addition, the amount of lateral excursion two weeks after surgical correction of more severe types of zygomatic arch fractures was less compared with other fracture types. Patients with more severe fractures may need to be followed for a longer period of time in order to regain the normal mandibular movement range.

Shape analysis of the preorbital bar in caviomorph rodents.

The highly specialised masticatory apparatus of rodents raises interesting questions about how their skull withstands the intensive and sustained forces produced by biting on hard items. In these mammals, major systematics were explored for a long time based on the adductor muscles' architecture and the related bony structures. The infraorbital foramen stands out, where a hypertrophied head of the zygomaticomandibular muscle passes through-in hystricomorphous rodents-as a direct consequence of the lateral and posterior shift of the preorbital bar. Interestingly, this bar moved laterally and backwards-enlarging the foramen-but it never disappeared throughout evolution, even showing morphological convergence among rodents. Previous research proposed this bar as behaving mechanically similar to the postorbital bar in ungulates, i.e., a safety structure against torsion stress while chewing. We analysed its morphology by mathematically modelling it under bending and torsion scenarios (linearly and elliptically shaped, respectively), and as for biting load propagation (catenary curve). Although the preorbital bar primarily seems to be shaped for withstanding torsional stress (as the postorbital bar in ungulates) and as an escaping point for force propagation, these forces are not a consequence of chewing and grinding foods, but preventing the zygomatic arch from failing when the powerful laterally-displaced jaw adductor muscles are pulling the dentary upwards at biting.

Minimal intervention for neurofibromatosis type I manifestations: A case report.

INTRODUCTION AND IMPORTANCE: Neurofibromatosis type I (NF1, OMIM: 162200) is a benign, autosomal dominant, tumorigenic predisposing syndrome with variable manifestations. Both neurofibromatosis and soft tissue sarcomas are associated with the formation of hematomas. Moreover, skeletal manifestations of NF1 include focal or generalized forms and expansive or infiltrative growth types. CASE PRESENTATION: A 19-year-old NF1 female patient presented with an expanding post-traumatic facial hematoma that resembled a soft-tissue tumor at initial presentation. A congenital neck mass was noted ipsilateral to her craniofacial skeletal deformities. Multiple imaging modalities were used to aid diagnosis, and urgent surgical intervention of the expanding facial lesion was performed. Her neck lesion and skeletal deformities were monitored, and her recovery was uneventful at 1-year follow-up, with no progression. CLINICAL DISCUSSION: A palpable, non-pulsatile soft tissue mass is a common clinical presentation with a diverse differential diagnosis. Despite the low incidence of post-traumatic vascular injuries and lesions in the maxillofacial region, neurofibromatosis-associated vasculopathy remains an underestimated and serious manifestation of NF1. The reported zygomatic arch deformity is believed to be unique. However, the NF1 tumor-associated skeletal malformations are not linearly related. CONCLUSION: NF1 is a multisystem disorder necessitating an early multidisciplinary team approach. Minimal intervention can help convert an emergent operation into an urgent one and preclude the need for major surgery. The case illustrated a rare example of simultaneous affection of soft tissue and jaw bones in NF1 patients.

A Clinical and Anatomical Study on the Localization of the Temporal Branch of the Facial Nerve Crossing the Zygomatic Arch / Estudio Clínico y Anatómico sobre la Localización del Ramo Temporal del Nervio Facial que Cruza el Arco Cigomático

SUMMARY: To clarify the path of the temporal branch of facial nerve (TB) crossing the zygomatic arch (ZA). Eighteen fresh adult heads specimens were carefully dissected in the zygomatic region, with the location of TB as well as its number documented. The hierarchical relationship between the temporal branch and the soft tissue in this region was observed on 64 P45 plastinated slices. 1. TB crosses the ZA as type I (21.8 %), type II (50.0 %,), and type III (28.1 %) twigs. 2. At the level of the superior edge of the ZA, the average distance between the anterior trunk of TB and the anterior part of the auricle is 36.36±6.56 mm, for the posterior trunk is 25.59±5.29 mm. At the level of the inferior edge of the ZA, the average distance between the anterior trunk of TB and the anterior part of the auricle is 25.77±6.19 mm, for the posterior trunk is 19.16±4.71 mm. 3. The average length of ZA is 62.06±5.36 mm. TB crosses the inferior edge of the ZA at an average of 14.67±6.45 mm. TB crosses the superior edge of the ZA at an average of 9.08±4.54 mm. 4. At the level of the ZA, TB passes on the surface of the pericranium while below the SMAS. The TB obliquely crosses the middle 1/3 part of the superior margin of the ZA and the junction of the middle 1/3 part and the posterior 1/3 part of the inferior margin of the ZA below the SMAS while beyond the periosteum. It is suggested that this area should be avoided in clinical operation to avoid the injury of TB.

El objetivo de estudio fue esclarecer el trayecto del ramo temporal del nervio facial (RT) que cruza el arco cigomático (AC). Se disecaron la región cigomática de 18 especímenes de cabezas sin fijar de individuos adultas y se documentó la ubicación del RT y su número de ramos. La relación jerárquica entre el ramo temporal y el tejido blando en esta región se observó en 64 cortes plastinados o P45. 1º El RT cruza el AC como tipo I (21,8 %), tipo II (50,0 %) y tipo III (28,1 %). 2º A nivel del margen superior del AC, la distancia promedio entre el tronco anterior de RT y la parte anterior de la aurícula fue de 36,36±6,56 mm, para el tronco posterior fue de 25,59±5,29 mm. A nivel del margen inferior del AC, la distancia promedio entre el tronco anterior del RT y la parte anterior de la aurícula era de 25,77±6,19 mm, para el tronco posterior era de 19,16±4,71 mm. 3º La longitud media de RT fue de 62,06±5,36 mm. EL RT cruzaba el margen inferior del AC a una distancia media de 14,67±6,45 mm. El RT cruzaba el margen superior del AC a una distancia media de 9,08±4,54 mm. 4º Anivel del AC, el RT pasaba por la superficie del pericráneo mientras se encuentra por debajo del SMAS. El RT cruza oblicuamente el tercio medio del margen superior del AC y la unión del tercio medio y el tercio posterior del margen inferior del AC por debajo del SMAS, más allá del periostio. Se sugiere que esta área debe evitarse en la operación clínica para evitar la lesión de la RT.

Stability of different fixation methods after reduction malarplasty under average and maximum masticatory forces: a finite element analysis.

BACKGROUND: Although titanium plates/screws are effective fixation methods (FM) after L-shaped osteotomy reduction malarplasty (LORM), the ideal FM remains controversial. This first finite element analysis (FEA) aimed to study the effect of various zygomatic body/zygomatic arch FM combinations and their placement vectors on the zygoma complex stability after virtual LORM under the effect of both average (150 N/mm2) and maximum (750 N/mm2) forces and three-dimensional (3D) mapping of stress and strain parameters distribution over the zygomatic bone, fixation methods, and total model. RESULTS: The fixation methods about the short-arm of the L-shaped osteotomy showed lower stress, strain, and displacement values than those across the long-arm osteotomy site. Combined with any zygomatic arch fixation methods (ZAFm), the two bicortical screws group (2LS) on the zygomatic body osteotomy site resulted in smaller displacements and the lowest zygoma bone stress and displacement when combined with Mortice-Tenon structure (MT) as zygomatic arch fixation method. Applied forces caused statistically significant differences in zygomatic bone stress (P < 0.001 and P = 0.001) and displacement (P = 0.001 and P = 0.002). CONCLUSION: All FMs both on the zygomatic body and zygomatic arch provide adequate zygomatic complex stability after LORM. The 2LS group showed better resistance than rectangular plate (RP) and square plate (SP) with lower stress concentrations. The L-shaped plate with short-wing on the maxilla (LPwM) is more stable than having the short-wing on the zygoma bone (LPwZ). Future prospective clinical studies are required to validate the current findings.

Difficulty of Arch Reduction with Gillies Temporal Approach in a Coronoid Hyperplasia Case.

Introduction: Bilateral coronoid hyperplasia is an abnormal elongation of the mandibular coronoid process which is rare in occurrence and causes progressive but slow reduction in mouth opening. In case of reduction in zygomatic arch fracture by Gillies temporal approach, the presence of bilateral coronoid hyperplasia can be a possible factor for hindrance and improper reduction. Material and methods: We propose a technical note to overcome this hindrance caused by the coronoid hyperplasia and propose tips and tricks to successful reduction in zygomatic arch. Results: Adequate reduction in the zygomatic arch and pretrauma mouth opening was achieved. Conclusion: Manual repositioning of the mandible during Gillies temporal approach along with ultrasound guidance leads to a satisfactory outcome.

Morphometric and morphological evaluation of temporozygomatic suture anatomy in dry adult human skulls.

This study aims to evaluate the position, morphometric, and morphological features of the temporozygomatic suture (TZS) located on the zygomatic arch (ZA) in dry adult human skulls. Thirty-two crania were evaluated. Measurements for the TZS were carried out using the ImageJ software. Morphometric measurements were carried out bilaterally in 23 crania and unilaterally in 9 crania (right: 4, left: 5). A total of 55 TZSs were analyzed. Localization of the TZS was determined according to the reference landmarks on the ZA. Morphologic features of the TZS evaluated in terms of "joint shape type" and "suture margin pattern". Descriptive statistics of the morphometric and morphologic variables were calculated. A statistically significant difference between the right and left sides was observed for the localization of the TZS (p < 0.05). TZS is located more anteriorly on the left side than the right side. Based on the "joint shape type", four types of TZS were observed: Type 1 (angular) (34.55%), Type 2 (curvy) (34.55%), Type 3 (oblique) (14.55%), Type 4 (horizontal) (16.36%). Based on the "suture margin pattern", five types of TZS were observed: Type A (linear) (12.73%), Type B (denticulate) (34.55%), Type C (serrated) (23.64%), Type D (mixt) (21.82%), Type E (fused) (7.27%). No significant association between the type and lateralization was found for both morphologic classifications. To the best of our knowledge, this is the first published report regarding the localization and morphologic classification of the TZS in adult human crania. Considering the TZS with its morphometric and morphological features may contribute to clinical or forensic medical evaluations.

Temporalis Muscle Transposition in Irreversible Facial Nerve Palsy: A Vestibular Approach.

Background The facial nerve plays a crucial role in innervating the motor supply of facial muscles, enabling essential facial expressions that facilitate human communication. Defects or damages to this nerve can have significant consequences, leading to functional, emotional, and social difficulties caused by the immobility of facial muscles. Patients suffering from irreversible facial nerve palsy often experience functional symptoms such as eyelid closure defects, mouth deviation, and limited movement. Methods This study aims to address these challenges and offer potential solutions for patients with irreversible facial nerve palsy. In this study, 18 patients (three males and 15 females) underwent temporalis transfer with an intraoral approach in the cranio-orbito-palpebral unity. Preoperative facial reanimation planning involved evaluating the smile's appearance on the unaffected side. Photographs were captured in various positions, and facial expressions were examined. Following this, botulinum toxin was injected into the normal side of the face seven days before the procedure to address the hyperactive condition of the mimic muscles. Results Temporalis transfer with an intraoral approach for oral commissure reanimation in the context of irreversible facial nerve palsy was performed. The surgical procedure combined coronal and orbital approaches and achieved the desired outcomes. Postoperative complications observed included hematomas and ossification. Functional outcomes, assessed using the House-Brackmann grading system, indicated a mean improvement of 2.5, signifying moderate dysfunction with normal tone and facial symmetry. Conclusion This intervention represents an alternative approach to actual techniques of facial palsy reanimation, especially in selected patients who can benefit from the absence of visible scars, such as young patients and those prone to hypertrophic and keloid scarring, as well as patients with non-prominent nasolabial folds.

Facial shaping filled with autologous high density fat in zygomatic arch area / 中华医学美学美容杂志

Objective:To explore a simple and effective method to improve the facial shape coordination for patients.Methods:From May 2015 to May 2020, 36 female patients (aged 24-32 years, mean 26.8 years) who were required to change face shape were enrolled in Zhengzhou Mylike Medical Cosmetology Hospital to improve face shape by adjusting frontaI arch width combined with autologous high-density fat transplantation.Results:Thirty-three patients (91.7%) were satisfied (31 satisfied, 2 basically satisfied). Three patients were not satisfied with the filling effect, and two of them were satisfied after the second filling (3 months after operation). 35 of the 36 patients were satisfied, accounting for 97.2%, only 1 case was dissatisfied. No other compIications such as fat liquefaction were observed. The mean morphological surface index of patients was 90.2 before operation and 88.1 after operation, showing significant improvement.Conclusions:Autologous high density fat transplantation is a good method to adjust the coordination of the frontal arch.

Digital measurement of anatomical morphology of a zygomatic arch / 中华医学美学美容杂志

Objective:To analyze the anatomical morphology of the zygomatic arch for reduction malarplasty.Methods:Computed tomography (CT) data were obtained from the electronic records of 45 patients in the Tianjin Stomatological Hospital from January 2018 to February 2020. Among them, there were 30 patients with normal protrusion of zygoma (group A) and 15 patients with prominent protrusion of zygoma (group B). The data were imported into modeling and analysis software (Mimics). Left and right three-dimensional (3D) zygoma models were created through standard procedures. In the 3D models, a vertical cut of the zygomatic arch was done, and anatomical morphological characteristics of the zygomatic arch were obtained through bone data measurement and morphological observation. Mean values with 95% confidence intervals ( CI) were calculated for the positional data. Independent sample T-test was conducted on the positional data and anatomical morphology data of the zygomatic arch in the two groups. P< 0.05 was considered as statistically significant. Results:In group B, the anterior edge of the stabilization area was located in front of the articular tubercle point (15.12 mm, 17.16 mm). The posterior edge of the stabilization area was located in front of the articular tubercle point (7.11 mm, 8.24 mm). The posterior edge of the enlarged area was located in front of the articular tubercle point (3.17 mm, 3.94 mm). There were significant differences between group A and group B in the posterior edge of the stabilization area ( t= 2.41, P= 0.018), the posterior edge of the enlarged area ( t=2.58, P= 0.012), and the width of the unilateral face ( P<0.01). Conclusions:There exists a stabilization area of bone morphology and enlargement area in zygomatic arch. The anatomical morphology of the zygomatic arch is different in width of the unilateral face and location of the enlarged area between populations with normal protrusion and prominent protrusion of the zygoma.

Detection and diagnosis of cleidocranial dysplasia by panoramic radiography: a retrospective study.

BACKGROUND: Cleidocranial dysplasia (CCD) is a rare and underdiagnosed congenital disorder in dentistry. The purpose of this study was to illustrate and quantify the maxillofacial bone abnormalities detected on panoramic radiographs from a relatively large retrospective case series and to provide a series of diagnostic references for dentists to indicate the presence of disease and help in making an early and accurate diagnosis. METHODS: The dental panoramic radiographs of thirty CCD patients aged 11 to 45 years (18 males and 12 females) were examined retrospectively. The dentition states, including supernumerary teeth and impacted teeth, were recorded. Twelve quantified measurements were adopted to determine the abnormalities of maxillofacial bones, including the degree of the zygomatic arch downward bend, bicondylar breadth, ramal height, mandibular height, mandibular aspect ratio, mandibular body height, condylar height, coronoid height, distance between the coronoid process and the condyle, bigonial width, gonial angle and best-fit gonial circle diameter. The Wilcoxon rank-sum test was used to compare the findings of the CCD patients with those of their matched controls (n = 300). RESULTS: Supernumerary teeth were detected in 27 patients (90.0%), and all 30 patients presented impacted teeth. Compared to the matched controls, the CCD patients had a significantly larger degree of zygomatic arch downward bend (ZAD), a larger diameter of the best-fit gonial circle (BGC), and a shorter distance between the coronoid process and the condyle (DCC) in panoramic radiographs (P < 0.001). According to the reference cutoff values established from the 5th or 95th percentile of the measurements in the control group, ZAD higher than 6.90 mm, DDC less than 22.37 mm and BGC higher than 52.41 mm were significantly associated with the CCD features identified. Other panoramic measurements were not significantly different between the two groups. CONCLUSIONS: Panoramic radiographs had great value in the diagnosis of CCD. In this study, we identified some dental and maxillofacial features on panoramic radiographs from a relatively large retrospective case series of CCD. A series of reliable quantitative indicators were provided for dentists that can indicate the presence of disease and improve the diagnostic specificity.

A Modified Technique to Harvest Integrated Zygomatic Arch-Temporal Bone Flap: Clinical Experience.

Background: In skull base surgery, zygomaticectomy is an effective method to increase surgical exposure and reduce brain retraction. However, the traditional zygomaticectomy methods are complicated and more invasive. Objective: To improve the procedure of zygomaticectomy, we introduced a modified technique to harvest integrated zygomatic arch-temporal bone flap. Subjects and Methods: A modified technique to section the zygomatic arch integrated with the temporal bone flap was described in the present work. This technique was applied in eight skull base lesion patients. The improved surgical angle was measured using Osirix software. Results: The surgical exposure is satisfied and no temporal lobe contusion or severe complications occurred in the patients. An increased surgical angle was obtained by zygomatic arch removing, with a mean value of 13.31°. Conclusions: This integrated zygomatic arch-temporal bone flap technique achieved increased exposure, decreased temporal lobe retraction, and minimal bone loss, leading to better cosmetics and functional reconstructions.

Modified Temporal Incision for the Management of Zygomatic Arch fractures-A Retrospective Study for 7 Years.

Study Design: Retrospective cross-sectional study. Objective: The objective of this retrospective study was to evaluate the clinical outcomes of Modified temporal incision in the management of zygomatic arch fractures (ZAF). Patients and Methods: Records of 34 patients who underwent open reduction for zygomatic arch fractures were retrieved and included in the study between 2011 and 2018. These patients were followed up at 4 weeks, 8 weeks and 12 weeks respectively. Clinical parameters such as post-operative infection, hematoma, scarring, degree of mouth opening, palpability of plates, alopecia and weakness of temporal branch of Facial nerve recorded were analyzed for complications of modified temporal incision in the management of ZAF. Results: A thorough analysis of the clinical parameters revealed that at the end of 4 weeks scarring was present in 4 patients and temporal branch of Facial nerve weakness was present in 21 patients. None of the patients had hematoma, infection or palpability of miniplates. At the end of 8 weeks the only complication recorded was weakness of temporal branch of Facial nerve in 21 patients. By 12 weeks, all patients had complete recovery and none of the patient had weakness of temporal branch of Facial nerve. Conclusion: The results obtained proved that the Modified temporal incision can be considered as a reliable method in the management of zygomatic arch fractures. The incision can be adopted with confidence in suitable cases of zygomatic arch fractures without any permanent morbidity.

The importance of the mortice and tenon joint on the zygomatic arch in reduction malarplasty-a retrospective study.

The aim of this study was to compare two kinds of reduction malarplasty in terms of their bony consolidation. Patients that underwent reduction malarplasty were reviewed retrospectively. The medial movement of the zygomatic body and the zygomatic arch as well as the complications and satisfaction of patients were investigated. The surgical procedure entailed a classical or modified L-shaped osteotomy through intraoral and sideburn approaches. Two groups were distinguished, those for whom a mortice and tenon joint was formed on the zygomatic arch (Group I), and those that formed end-to-end bone contact (Group II). All the cases in Group I showed an improved facial contour with sufficient bone contact. A larger medial movement of the zygomatic arch was observed in Group I (4.54 ± 0.41 mm) than in Group II (2.72 ± 0.29 mm) (P = 0.016). More bone malunion was observed in six cases of Group II (P = 0.030) and four required a second operation. In conclusion, this study indicates that the mortice and tenon approach is preferable when the priority is bony consolidation.

Liposuction of the Zygomatic Arch Area: A Novel Concept to Improve the Midface Contour.

BACKGROUND: An ovoid, slender face with a smooth contour is preferred in oriental esthetics. We developed a novel concept to achieve a slimmer and harmonious midface contour by liposuction of the projection area of the zygomatic arch. METHODS: A cadaver study including anatomical dissection and histologic examination were conducted to better understand the soft tissue structure of the projection area of the zygomatic arch and the vital technique for liposuction. For the clinical evaluation, 49 patients with midface hypertrophy who underwent liposuction of the zygomatic arch area from January 2016 to June 2021 were retrospectively reviewed. RESULTS: Cadaver study showed that abundant fatty tissue existed in the subcutaneous layer of the zygomatic arch area. The liposuction manipulation was precisely limited to the subcutaneous fat layer, and nerve branches were observed in the deeper loose areolar tissue plane. Of the 49 patients enrolled in this study (including 98 zygomatic arch areas), the median fat removal volume per zygomatic arch area was 3.0 (2.0, 5.0) mL. The subcutaneous fat thickness was significantly decreased postoperatively [median 9 (6, 10) mm vs. 1 (1, 2) mm per zygomatic arch area, P < 0.001]. All patients were satisfied with their postoperative outcomes. Only three patients underwent slight depression of the liposuction area during making facial expression after surgery and subsequently recovered. CONCLUSIONS: Liposuction of the zygomatic arch area is effective in improving midface hypertrophy and achieving a harmonious facial contour with a low risk of complications. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Tratamento de fratura isolada do arco zigomático - relato de caso / Treatment of isolated fracture of the zygomatic arch - case report

Devido ao comprometimento estético funcional, as fraturas do arco zigomático (AZ) devem ser abordadas, o mais breve possível, com o objetivo de minimizar as sequelas. Há várias formas de tratamento descritas na literatura. O objetivo deste trabalho é relatar um caso clínico de fratura isolada do AZ tratada pela técnica de Keen sob anestesia local.

Due to functional aesthetic impairment, fractures of the zygomatic arch (ZA) should be addressed, as soon as possible, in order to minimize the sequelae. There are several forms of treatment described in the literature. The objective of this work is to report a clinical case of isolated ZA fracture treated by Keen's technique under local anesthesia.

Zygomaticomaxillary Fractures.

Fractures of the zygomaticomaxillary complex and zygomatic arch are common athletic injuries. Fracture displacement can lead to midfacial retrusion and widening, causing noticeable deformity. Associated signs and symptoms include hypoesthesia of the infraorbital nerve distribution, trismus, and subjective malocclusion. Operative treatment is indicated in cases of significant displacement or functional disturbance. The approach and details of osteosynthesis are catered to the specific characteristics of the fracture. Technology, such as virtual surgical planning, intraoperative navigation, and intraoperative imaging, has the potential to improve accuracy of treating challenging fractures.

Intra-operative application of ultrasonography (USG) for reduction of zygomatic arch fracture.

Zygomatic arch fractures are the most common facial fractures or second in frequency after the nasal fractures. The high incidence of zygomatic fractures probably relates to its prominent position in the facial skeleton; hence, it is frequently exposed to fractures. This case report presents an left-sided isolated zygomatic arch fracture after subjected to routine investigations and radiographs like submentovertex and CT scans. The patient was operated under general anesthesia for the reduction of zygomatic arch by Gille's temporal approach with the use of Ultrasound intra-operatively. Recommendation for the use of ultrasonography in the identification of zygomatic arch fractures intra-operatively operatively.

Positions and Types of Pterion in Adult Human Skulls: A Preliminary Study.

BACKGROUND: A trauma to the skull in the area of the pterion usually causes rupture of the middle meningeal artery leading to life- threatening epidural hematoma. The objective of the study is to assess the prevalence of different types of pterion and to determine its location using valuable bony landmarks. METHODS: On 90 dry adult human skulls of unknown sex, age and nationality the distance of different landmarks from pterion was measured using stainless steel sliding Vernier caliper. The data were analyzed using SPSS version-20 and an independent t-test analysis was implemented. A value of P< 0.05 was considered as statistically significant. RESULTS: A higher occurrence of sphenoparietal type of pterion with the absence of frontotemporal type was noted. About 23% and 77% of the suture types are found to be unilateral and bilateral, respectively. There was a statistically significant difference between right and left sides of the skull in distances from the center of pterion to frontozygomatic suture, root of zygomatic arch, inion and in central thickness pterion. CONCLUSION: This study showed that the most prevalent type of pterion is sphenoparietal, and revealed asymmetry in the distances from center of pterion to frontozygomatic suture, root of zygomatic arch and inion, and its central thickness. Such findings could offer worthy information about the type and location of pterion, which could be relevant to anatomists, neurosurgeons, forensic medicine specialist and anthropologists.