Study of landmarks in dried skulls in a Brazil population

Craniofacial bone variations, considered to be radiological landmarks, have been studied since the beginningof the century using dried skulls and cadavers. These pitfalls are important bone landmarks used in theplanning and execution of anesthetic and surgical procedures. The present study analyzed craniofacial bonevariations in dried skulls in terms of gender and laterality. Supraorbital foramen (SOF), mastoid foramen(MF), parietal foramen (PF), accessory oval foramen (aOF), anterior ethmoidal foramen (AEF), intermediateethmoidal foramen (iEF), posterior ethmoidal foramen (PEF), precondylar tubercle (PCT), metopism andsutural bones were assessed in male (n=20) and female (n=11) dried skulls by direct observation and using aMitutoyo caliper. No statistically significant differences were observed between genders as to SOF distancesto the medial nasal prominence and to superior orbital ridge, in both sides of skulls. The same was observedfor distances between FP and sagittal line and between FP and lambdoid suture. No multiple foramina weredetected. aOF was observed in 80.96% of skulls. Right aEF, iEF and PEF prevailed in female skulls. PCT wereseen in 35.5% of female skulls and in 64.5% of male skulls. MF occurrence was higher in right male skulls,and multiple foramina were present in 60% of male skulls (both sides), and in 36.4% of female skulls (bothsides). Only one skull presented sutural bone. No metopism was observed. The identification and recordingof craniofacial variations is important in the preparation of anesthetic blocks in surgical procedures and in theevaluation of regional neurovascular anatomy, to avoid misinterpretations in planning. This study confirms theexistence of significant morphological variations in terms of gender and side in a given population.

Morphometric analysis related to the transcondylar approach in dry skulls and computed tomography / Análisis morfométrico del acesso transcondilar en cráneos secos y en tomografia computarizada

The transcondylar approach (TA) has been used in surgeries to access lesions in areas close to the foramen magnum (FM) and is performed directly through the occipital condyle (OC) or through the atlanto-occipital joint and adjacent portions of the same. The objective of this study is to examine anatomical variations related to the TA by morphometric parameters of the FM, OC and of the hypoglossal canal (HC) in dry skulls and in computed tomography (CT). In 111 skulls, characteristics of the HC, and measures related to the FM, the HC and to the OC were examined. In CT, the measurements obtained bilaterally in 10 patients who underwent examination of the skull base in 1 mm-thick axial helical cuts were the distances from the outer half of the clivus to the opening of the HC; from the lower portion of the OC to the middle of HC; from the inner half of the clivus to the intracranial opening of the HC and to the midpoint of the HC; from the HC extracranial opening to the lower portion of the OC and to the outer half of the clivus. The results of CT measurements are consistent to previous studies of morphometric variations related to the TA, with no significant difference between the measurements obtained in the right and in the left sides, or related to gender. The data obtained by three-dimensional CT images are important in assessing the morphometric variations of pre-surgical patientsof TA.

El acceso transcondilar (AT)ha sido utilizado comoun procedimiento quirúrgico para lesiones cercanas al foramen magnum(FM)y se realizadirectamente a través delcóndilooccipital (CO)o por medio delas porciones atlanto-occipitalconjuntay adyacentesde lamisma.El objetivo del presenteestudio fue examinarlas variaciones anatómicas relacionadas con el AT mediantelos parámetros morfométricos del FM, CO y el canal delhipogloso (CH) en cráneossecos y tomografía computadorizada (CT). En 111 cráneos fueron examinadas las característicasdel CH y tomadas medidas relacionadas con el FM, CO y CH. En la CT, las mediciones se obtuvieron de forma bilateral en10 pacientes que se sometieron a exámen de la base del cráneo en corte axial helicoidal de 1mm de espesor. Las medidas tomadas fueron las distancias: de la mitad exterior del clivus a la apertura del CH; de la parte inferior de las emisiones de CO a la mitad del CH; de la mitad interna del clivus a la apertura intracraneal del CH y hasta el punto medio del CH; de la apertura extracraneal del CH a la parte inferior de las emisiones de CO y hasta la mitad exterior del clivus. Los resultados de las mediciones de CT son consistentes con estudios prévios de los cambios morfométricos en relación con AT, sin diferencia significativa entre las mediciones obtenidas en el lado derecho e izquierdo y ni en relación con el sexo. Los datos obtenidos a través de imágenes en tres dimensiones de CT son importantes para evaluarlas variaciones morfométricas de pre-quirúrgicos en el AT.

Morphometric Analysis of the Greater Palatine Foramen in Dry Southern Brazilian Adult Skulls / Análisis Morfométrico del Foramen Palatino Mayor en Cráneos de Individuos Adultos del Sur de Brasil

The greater palatine foramen (GPF) conducts the greater palatine nerve, responsible for the innervation of the posterior hard palate. The morphometric knowledge of the GPF is essential in the anesthetic interventions required in maxillofacial surgical procedures. The aim of this study was to evaluate the location and shape of the GPF in dry skulls of adults from Southern Brazil. Male (n = 65) and female (n = 29) skulls were studied, and the distance measurements from the middle of the GPF to the mid-sagittal plane (MSP) and to the posterior border of the hard palate (PBHP) were analyzed using a digital caliper and a ruler. The mean GPF-MSP distance in the right and in left sides of male skulls were 15.6 mm and 15.4 mm, respectively, and in female skulls, 15.63 mm in the right side and 15.47 mm in the left. The mean GPF-PBHP distance on the right side was 3.5 mm in male skulls, and 3.1 mm in female skulls, and on the left side, 3.6 mm and 3.2 mm in male and female skulls, respectively. Student's t-test showed no significant difference in the GPF-MSP and GPF-PBHP mean distances when compared to gender and to the left and right sides. The predominant GPF shape was ovoid, followed by lancet or slit, and round. This study provides comparisons of ethnic data, which may help clinically in oral and maxillofacial anesthesia.

El foramen palatino mayor (FPM) da paso al nervio palatino mayor, responsable por la inervación de la región posterior del paladar. El conocimiento morfométrico del FPM es importante en las intervenciones anestésicas requeridas durante los procedimientos quirúrgicos maxilofaciales. El objetivo de este estudio fue evaluar la ubicación y la forma del FPM en cráneos de individuos adultos del Sur de Brasil. Se estudiaron 65 cráneos de hombres y 29 de mujeres, midiéndose la distancia desde el centro del FPM al plano mediano (PM) y al margen posterior del paladar duro (MPPD), utilizándose un cáliper digital y una regla milimétrica. La distancia promedio de FPM-PM en los lados derecho e izquierdo de los cráneos de hombres fue de 15,6 mm y 15,4 mm, respectivamente, y en los cráneos de mujeres, fue de 15,63 mm en el lado derecho y 15,47 mm en el izquierdo. La distancia media de FPM-MPPD en el lado derecho fue de 3,5 mm en cráneos de hombres y 3,1 mm en cráneos de mujeres y en el lado izquierdo de 3,6 mm y 3,2 mm en cráneos de hombres y mujeres, respectivamente. La prueba t de Student no mostró diferencias significativas en los promedios de las dos distancias (FPM-PM y FPM-MPPD), comparando sexos y lados. La forma ovoide del FPM fue predominante, seguida de las formas de hendidura y redonda. Este estudio proporciona comparaciones de datos étnicos, que pueden ayudar a la clínica en anestesia oral y maxilofacial.

Nutrient Foramina in the Upper and Lower Limb Long Bones: Morphometric Study in Bones of Southern Brazilian Adults / Forámenes Nutricios en los Huesos Largos de los Miembros Superiores e Inferiores: Estudio Morfométrico en Huesos de Adultos del Sur de Brasil

The major blood supply to long bones occurs through the nutrient arteries, which enter through the nutrient foramina. This supply is essential during the growing period, during the early phases of ossification, and in procedures such as bone grafts, tumor resections, traumas, congenital pseudoarthrosis, and in transplant techniques in orthopedics. The present study analyzed the location and the number of nutrient foramina in the diaphysis of 885 long bones of the upper and lower limbs of adults: 174 humeri, 157 radii, 146 ulnae, 152 femora, 142 tibiae and 114 fibulae. The location of the nutrient foramina is predominant on the anterior aspect of the upper limb long bones, and on the posterior aspect of the lower limb long bones. The majority of the bones studied had a single nutrient foramen, which may represent a single source of blood supply. The mean foraminal index for the upper limb bones was 55.2 percent for the humerus, 35.7 percent for the radius, and 37.9 percent for the ulna, and for the lower limb bones, 43.7 percent for the femur, 32.7 percent for the tibia and 46.1 percent for the fibula. This study recorded data related to the population of Southern Brazil, providing ethnic data to be used for comparison and that may help in surgical procedures and in the interpretation of radiological images.

El importante aporte de sangre para los huesos largos se produce a través de las arterias nutricias, que penetran por los forámenes nutricios. Este suministro es esencial durante el período de crecimiento, las primeras fases de osificación y en los procedimientos como injertos óseos, resecciones tumorales, traumas, pseudoartrosis congénita y en las técnicas de trasplante en ortopedia. El estudio determina la ubicación y el número de forámenes nutricios en las diáfisis de 885 huesos largos de los miembros superiores e inferiores pertenecientes a individuos adultos. Fueron estudiados 174 húmeros, 157 radios, 146 ulnas, 152 fémures, 142 tibias y 114 fíbulas. La ubicación de los forámenes nutricios era predominante en la parte anterior de la diáfisis de los huesos largos del miembro superior y en la parte posterior de los huesos largos del miembro inferior. La mayoría de los huesos estudiados tenía un solo foramen nutricio, representando una sola fuente de suministro de sangre. El índice medio foraminal en los huesos del miembro superior fue de 55,2 por ciento para el húmero, 35,7 por ciento para el radio, y 37,9 por ciento para el ulna; en los huesos del miembro inferior fue 43,7 por ciento para el fémur, 32,7 por ciento para la tibia y 46,1 por ciento para la fíbula. Este estudio registró datos relativos a la población del Sur de Brasil, proporcionando antecedentes étnicos que además puedan servir de ayuda en los procedimientos quirúrgicos y en la interpretación de imágenes radiológicas.

Location of the mental foramen in dry mandibles of adultindividuals in Southern Brazil

The mental foramen (MF) guides the mental nerve which is responsible for the sensible innervation of themandibular area. It is important to know the anatomical variations of the MF for locational blockage of theincisor nerve in periapical surgeries involving molars and premolars, and in other buccomaxillofacial surgicalprocedures as well. This study aims to analyze variations in the MF site in dry mandibles of adult subjects inSouthern Brazil. Eighty mandibles were analyzed, and the measurements of the distance from the sagittalmidline to the center of the MF (MLF); the distance from the lower rim of the mandible to the center ofthe MF (LRF); the location of the MF relative to its alignment with the mandible teeth, and the incidenceof double mental foramens (DMF) were checked. The analyzed parameters were related to each mandible’slaterality. Statistical analysis was carried out through Student’s t test. Results indicate that the prevalentposition of the MF in the right and left sides was posterior to the first premolar. There was no significantdifference between the right and left sides regarding MLF, and LRF showed a significant difference betweensides, greater on the right side. There was a prevalence of the DMF on the right side of the mandibles. Theseresults are important for the preparation and conduction of surgical procedures in order to prevent injury tothe involved neurovascular structures.

Morphometric aspects of the jugular foramen in dry skullsof adult individuals in Southern Brazil

The jugular foramen (JF) lies between the occipital bone and the petrosal portion of the temporal bone, andit allows for the passage of important nervous and vascular elements, such as the glossopharyngeal vagusand accessory nerves, and the internal jugular vein. Glomic tumors, schwannomas, metastatic lesions andinfiltrating inflammatory processes are associated with this foramen, which can account for injuries of relatedstructures. Variatons of the JF were already reported regarding shape, size and laterality in one only skull,besides differences related to sex, race and laterality domain, which makes the study of these parameters in thepopulation of southern Brazil significant. Objective: this paper wants to conduct the morphometric analysisof the JF of 111 dry skulls belonging to males and females. Results: the latero-medial the anteroposteriormeasurements showed significant differences when genera were compared and side was compared, respectively.Of the total amount of the investigated skulls, 0.9% showed a complete septum on both sides; 0.9% showedincomplete septum, and 83.8% lacked the septum. The presence of a domed bony roof was noticed in 68.5%of skulls on both sides. Conclusion: the obtained results presented variations regarding some parameterswhen compared to previous studies, thus making it evident the significance of race in the morphometricmeasurements and characteristics of the JF, besides the relevance of studying the kind of impairment whichcan jeopardize important functions, as the cardiac innervation of the vagus nerve.