Desenvolvimento da Órtese de Descompressão Occipital (ODO) para pacientes críticos em unidades de terapia intensiva / Development of an Occipital Decompression Orthosis (ODO) for critically ill patients in intensive care units

Resumo Introdução Lesões por pressão são causadas por prolongado contato da pele com alguma superfície, levando a danos consideráveis de difícil recuperação. Terapeutas ocupacionais podem atuar na prevenção desses agravos por meio da confecção de dispositivos de tecnologia assistiva. Objetivos Apresentar o desenvolvimento de um dispositivo para prevenir e tratar lesões por pressão na região occipital: a Órtese de Descompressão Occipital. Método Esta é uma pesquisa exploratória aplicada através do método de gestão de projetos desenvolvida em quatro etapas. O dispositivo começou a ser desenvolvido em 2017 em um hospital de traumas referência na região metropolitana de Belém, PA, Brasil. Resultado Foi realizado um levantamento dos dispositivos disponíveis no mercado e, a partir disso, desenvolvida a Órtese de Descompressão Occipital. Essa órtese utiliza o colchão piramidal, que é um material de baixo custo que promove a baixa pressão constante no segmento occipital do paciente, e foi confeccionada a partir de avaliação antropométrica. Com base na literatura e em um estudo financeiro, criou-se um modelo aplicável na descompressão do segmento. Esse modelo alternativo apresenta baixo custo e é eficiente para prevenir lesões por pressão. Conclusão A Órtese de Descompressão Occipital segue em processo de aperfeiçoamento. Apesar de se embasar na literatura atual abordando a prevenção de lesões por pressão, ainda é necessário realizar um estudo científico criterioso para verificar sua eficácia. A Órtese de Descompressão Occipital apresenta limitações, principalmente quanto à aprovação de sua utilização por instituições hospitalares.

Abstract Introduction Pressure ulcers (PU) are caused by prolonged contact of the skin with a surface, leading to significant damage that is difficult to recover from. Occupational therapists can play a role in preventing these injuries through the creation of assistive technology devices. Objectives To present the development of a device to prevent and treat PU in the occipital region: the Occipital Decompression Orthosis (ODO). Method This is an exploratory study applied using the project management method and developed in four stages. The device began to be developed in 2017 in a reference trauma hospital in the metropolitan region of Belém, state of Pará, Brazil. Results A survey of devices available on the market was conducted, from which the ODO was developed. This orthosis uses the pyramidal mattress, a low-cost material that provides constant low pressure on the patient's occipital segment and was designed through an anthropometric assessment. Based on a literature review and a financial study, a model was created for decompression of the segment. This alternative model is low-cost and effective in preventing PU. Conclusion The ODO is still under a refinement process. Although it is based on current literature addressing pressure injury prevention, it is still necessary to conduct a rigorous scientific study to verify its efficacy. The ODO presents limitations, especially regarding its approval for use by hospitals.

Modified surgical method for supra- and infratentorial epidural hematoma and related anatomical study of the squamosal part of the occipital bone / 西安交通大学学报(医学版)

Objective: To explore the modified surgical method of supra- and infratentorial epidural hematoma (SIEDH) and analyze the related anatomy of the occipital bone. Methods: CT scan data of 30 adult patients with no history of craniocerebral trauma were collected in our hospital from January to August 2019. The median sagittal plane was taken to define line A (from lambdoid suture to the extraoccipital turbercle) and line B (from extraoccipital turbercle to the posterior edge of the foramen magmun). The angle θ was defined between the two lines. The mean value of θ was analyzed for comparison between genders and for exploration of the anatomical basis of single supratentorial craniotomy for SIEDH. Eight patients with SIEDH were recruited in the same period to analyze the procedure and results of the modified surgical method. Results: The average angle of the θ was (117.4±4.3)° for men and (130.0 ±4.9)° for women; the minimum was 108.3° for men and the maximum was 138.7 ° for women. The θ was smaller in men than in women (P<0.001). The smaller the angle was, the more conductive it was to detect the lesions from superior to inferior tentorial apartment. The bone flaps of the eight patients were designed above the transverse sinus. During the operation, epidural hematoma was completely removed, and no skull defects occurred like in conventional supra-inferior tentorial craniotomy. Conclusion: The supratentorial craniotomy above the tranverse sinus has reliable anatomical basis and is an effective surgical method for SIEDH.

​Occipital Bone Thickness Mapping for Safe Occipitocervical Fusion: An Observational Study

Introduction: There are various diseases and anomalies in humans which require occipitocervical fusion using medial orlateral occipital screw placement along with rod or plate placement.[1] There are many ongoing arguments regarding the safearea for screw placement on the occiput during fusion techniques. Morphological analysis of occipital bone thickness providesconfidence in placing screws. Here, we try mapping occipital bone using computed tomography (CT) which would benefit forsafe fusion in population of southern Tamil Nadu.Materials and Methods: We randomly selected the CT scans of 50 patients in the age group of 20–60 years, and occipitalbone thickness mapping is done and tabulated and compared with the previous studies from different demographical areas.Results: The maximum thickness of the occipital bone was at the level of the external occipital protuberance (EOP) at 16.2 mm.Areas with thicknesses >8 mm were more frequent at the EOP and up to 2 cm in all directions, as well as up to 1 cm in alldirections at a height of 1 cm inferiorly, and up to 3 cm from the EOP inferiorly in males and it’s up to 2 cm in females. Themale group tended to have a thicker occipital bone than the female group, and the differences were significant around the EOP.Based on these data, there are 10 safe points for males which include: M0, M1, M2, M3, L1, L2, R1, R2 at level 0, L1, and R2at level 1 and 9 safe points for female which include all the above except M3.Conclusion: There is variability in the thickness of occipital bone in adult people from different demographic areas andthere is also a significant difference between male and female patients. Hence, this study helps in pre-operative planning inoccipitocervical fusion in people of this region.

Surgical treatment of a massive neurofibroma of the head and neck in a patient with neurofibromatosis type 1: a case report / Tratamiento quirúrgico de un neurofibroma masivo de cabeza y cuello en un paciente con neurofibromatosis tipo 1: reporte de un caso

SUMMARY: Neurofibromatosis type 1 (NF1) is a rare autosomal dominant neurogenetic disease with variable clinical manifestations, which are primarily manifested as neurofibromas, café-au-lait macules (CALMs) and skeletal deformities. Although generally benign, expansile neurofibromas that are characteristic of NF1 readily lead to disturbing deformities. It is often difficult to surgically extirpate a tumor that involves these important tissues or organs. We report a rare case of a patient with neurofibromatosis Type 1. The patient presented with a congenital giant scalp neurofibroma and CALMs in the occipito-cervical region, in addition to ear and occipital deformities. We performed a challenging surgical intervention (a near-total resection) to reduce the tumor burden and rehabilitate the appearance and function of the patient while preserving the intracranial tissue structure. Here, we review this case and analyze the clinical manifestations, diagnosis and management of NF1.

RESUMEN: La neurofibromatosis tipo 1 (NF1) es una rara enfermedad neurogenética autosómica dominante, con manifestaciones clínicas variables, que se manifiestan principalmente como neurofibromas, máculas café con leche (CALM) y deformidades esqueléticas. Generalmente los neurofibromas expansivos benignos que son característicos de NF1 conducen fácilmente a deformidades exageradas. A menudo es difícil extirpar quirúrgicamente un tumor que involucra estos tejidos u órganos importantes. Presentamos un caso raro de un paciente con neurofibromatosis tipo 1. La paciente presentó un neurofibroma congénito gigante del cuero cabelludo y CALM en la región occipitocervical, además de deformidades del oido y región occipital. Realizamos una intervención quirúrgica desafiante (una resección casi total) para reducir la carga tumoral y rehabilitar la apariencia y función de la paciente mientras se preservó la estructura del tejido intracraneal. Aquí, revisamos este caso y analizamos las manifestaciones clínicas, el diagnóstico y el tratamiento de NF1.

Arachnoid Granulations Mimicking Multiple Osteolytic Bone Lesions in the Occipital Bone

We report a rare case of arachnoid granulations mimicking multiple osteolytic bone lesions. A 66-year-old woman was admitted to a local clinic for a regular checkup. Upon admission, brain CT showed multiple osteolytic lesions in the occipital bone. These needed to be differentiated from multiple osteolytic bone tumor. Subsequent brain MRI revealed that the osteolytic lesions were isointense to cerebrospinal fluid, hyperintense on T2-weighted image, hypointense on T1-weighted image, and with subtle capsules around the osteolytic lesions that were visible after gadolinium injection. A bone scan revealed no radiotracer uptake. The lesions were in both the transverse sinuses and the torcular herophili. With typical radiological appearances of the lesions, the osteolytic lesions were diagnosed as multiple arachnoid granulations. No further treatment was planned. A 1-year follow-up brain CT scan revealed no change. We should consider the possibility of arachnoid granulations when multiple osteolytic lesions are observed in the occipital bone.

Congenital Cholesteatoma of Mastoid Temporal Bone and Posterior Cranial Fossa Treated with Transmastoid Marsupialization / 대한이비인후과학회지

A congenital cholesteatoma is a benign mass formed from the keratinizing stratified squamous epithelium. It usually occurs in young children's anterosuperior part of the middle ear. A congenital cholesteatoma which originates from mastoid temporal bone or expands to posterior cranial fossa is rare. Standard treatment of an intracranial cholesteatoma is surgical removal with craniotomy. A 69-year-old woman was diagnosed with a congenital cholesteatoma of mastoid temporal bone that expanded to the posterior cranial fossa, which was successfully treated with transmastoid marsupialization without craniotomy. This is a first documented case of a congenital cholesteatoma of mastoid temporal bone that expanded to posterior cranial fossa, which was successfully treated with transmastoid marsupialization without craniotomy.

Morphological Analysis on the Occipital Condyles and Review of the Literature / Análisis Morfológico de los Cóndilos Occipitales y Revisión de la Literatura

Most anatomical and biomechanical studies on the craniovertebral junction have involved morphological or morphometric analysis on the occipital condyles. Some of these studies have provided important findings based on different surgical procedures. The shape, size and angle of the occipital condyles and the locations of the intracranial and extracranial orifices of the hypoglossal canal are highly important because they may affect the lateral approaches to the craniovertebral junction. To determine the frequency of occurrence of different morphological types of occipital condyle. 214 occipital condyles in 107 dry human skulls were analyzed and the classification of their morphological types was determined through assessing digitized photographic images. Among the 107 skulls analyzed, 59.8 % were male and 40.2 % were female. Their ages ranged from 11 to 91 years, with a mean of 57.56 years. Of the total of 10 morphological types of occipital condyle that were found, more than 50 % were of the "8", "S" and ring types. Condyles of "8" and "S" shape were the main types found in male skulls: the "8" shape prevailed on the left side and the "S" shape on the right side. However, in female skulls, these two types had equal bilateral distribution.

La mayor parte de los estudios anatómicos y biomecánicos de la unión cráneo-vertebral han sido realizados sobre el análisis morfológico o de la morfometría de los cóndilos occipitales. Algunos de estos trabajos tienen previsto importantes hallazgos basados en diferentes procedimientos quirúrgicos. De tal forma, el tamaño y ángulo del cóndilo occipital bien como su localización de los orificios intracraneales y extracraneales del canal hipogloso son de gran importancia, ya que pueden afectar a los enfoques laterales de la unión cráneo-vertebral. El objetivo del estudio fue determinar la prevalencia de los tipos morfológicos de cóndilos occipitales. Fueron analizados 214 cóndilos de 107 cráneos secos de humanos y la clasificación de los tipos morfológicos fue determinada a partir de los análisis de estudio de imágenes fotográficas digitalizadas. De los 107 cráneos que fueron analizados, 59,8 % eran de sexo masculino y 40,2 % de sexo femenino, cuyas edades comprendidas entre 11 y 91 años con una media de 57.56 años. De un total de 10 tipos morfológicos de los cóndilos occipitales encontrados, más del 50 % eran de tipo ocho, S y anillo. Los cóndilos en forma de "8" y "S" fueron los principales tipos encontrados, en el sexo masculino, la forma en "8" prevaleció en el lado izquierdo, y el tipo morfológico en "S", en el lado derecho del cráneo. Mientras que en el sexo femenino esos dos tipos tuvieron una equitativa distribución bilateral.

Postoperative Increase in Occiput-C2 Angle Negatively Impacts Subaxial Lordosis after Occipito-Upper Cervical Posterior Fusion Surgery

STUDY DESIGN: Retrospective case series. PURPOSE: To elucidate the impact of postoperative occiput-C2 (O-C2) angle change on subaxial cervical alignment. OVERVIEW OF LITERATURE: In the case of occipito-upper cervical fixation surgery, it is recommended that the O-C2 angle should be set larger than the preoperative value postoperatively. METHODS: The present study included 17 patients who underwent occipito-upper cervical spine (above C4) posterior fixation surgery for atlantoaxial subluxation of various etiologies. Plain lateral cervical radiographs in a neutral position at standing were obtained and the O-C2 angle and subaxial lordosis angle (the angle between the endplates of the lowest instrumented vertebra (LIV) and C7 vertebrae) were measured preoperatively and postoperatively soon after surgery and ambulation and at the final follow-up visit. RESULTS: There was a significant negative correlation between the average postoperative alteration of O-C2 angle (DO-C2) and the average postoperative alteration of subaxial lordosis angle (Dsubaxial lordosis angle) (r=-0.47, p=0.03). CONCLUSIONS: There was a negative correlation between DO-C2 and Dsubaxial lordosis angles. This suggests that decrease of mid-to lower-cervical lordosis acts as a compensatory mechanism for lordotic correction between the occiput and C2. In occipito-cervical fusion surgery, care must be taken to avoid excessive O-C2 angle correction because it might induce mid-to-lower cervical compensatory decrease of lordosis.

Occipital Bone Fossa Associated with the Position of Rectus Capitis Posterior Minor Muscle / Fosa en el Hueso Occipital Asociado a la Posición del Músculo Recto Posterior Menor de la Cabeza

Rectus Capitis Posterior Minor muscle (RCPm) is one of the deepest and shorter muscles of the posterior region of the neck. RCPm arises from the posterior tubercle on the posterior arch of atlas and inserts on the squamous part of the occipital bone, inferior to the inferior nuchal line and lateral to the external occipital crest at midline. Based on their anatomical location, and their functional role, is considered to be a head extender muscle and an active element in the stabilization of the occipitoatlantal joint. During routine examination of the skulls, in the Morphology Laboratory of the Basic Biomedical Sciences Department, University of Talca, Chile, two unusual fossas were found in the squamous part of occipital bone, of an adult human skull of masculine sex. No other significant bony anomaly was noted, but it is observed that the elevations and depressions are well marked in the skull. The anatomical location of this fossa suggests a relationship with the RCPm muscle that is described in the same location of this finding. Therefore, it is postulated that prolonged improper posture from an early age, could generate a mechanical compression which would result in the finding fossas; this based on Wolff's law, which states that the bone tissue adapts to the mechanical demands placed on him.

El músculo Recto Posterior Menor de la Cabeza (RCPm) corresponde a uno de los músculos más profundos y cortos de la región posterior del cuello. Se origina en el tubérculo posterior del arco posterior de atlas y se inserta en la parte escamosa del hueso occipital, inferior a la línea nucal inferior y lateral a la cresta occipital externa a nivel de la línea mediana. En relación a su localización anatómica y a su funcionalidad, es considerado un músculo extensor de cabeza y un elemento activo en la estabilización de la articulación atlanto-occipital. Durante la inspección rutinaria de cráneos en el Laboratorio de Morfología del Departamento de Ciencias Básicas Biomédicas de la Universidad de Talca, se encontraron dos fosas inusuales en la porción escamosa de la cara exocraneal del hueso occipital de un cráneo humano adulto de sexo masculino. En la inspección no se registraron otros hallazgos, pero se observó que tanto las depresiones como elevaciones del cráneo eran muy marcadas. Durante la búsqueda de referencias bibliográficas asociadas al caso, no se encontró literatura científica relacionada a este hallazgo. La localización anatómica de esta fosa sugiere una relación con el músculo RCPm que se describe a este nivel. Por consiguiente, se postula que una postura inapropiada prolongada desde muy temprana edad, podría generar una compresión mecánica que formaría dichas fosas. Lo anterior basado en la Ley de Wolff que plantea que el tejido óseo se adapta a las demandas mecánicas impuestas sobre él.

Radiological and anatomical study of posterior occipital condyle screw trajectory / 中华创伤杂志

Objective To investigate the optimal trajectory of posterior occipital condyle screw fixation via radiological and anatomical study.Methods Twelve adult craniocervical junction complete specimens were selected.The length,width and height of occipital condyle and the inclination angle of the longest axis were measured by CT scanning and reconstruction.Subsequently,occipital condyle screws were inserted with reference to CT measurements.After screw fixation,accuracy and safety of the placement of occipital condyle screw were verified by gross observation and CT scanning.Results Preoperative measurements of height and width of the occipital condyles indicated the placement of 4.0 mm bicortical screws was secure.Left vertebral artery horizontal sections of 2 specimens were slightly pressed without damage.CT scanning identified no damage to the inner or outer wall of the occipital condyle and the hypoglossal canal.Trajectory parameters between the right and left sides were slightly different,but no significant difference was observed (P ＞ 0.05).Average screw channel length and inclination angle were (20.8 ±2.6)mm and (37.1 ± 4.7)°respectively.Angle between screw and skull base tangent was observed as (8.5 ± 1.7) °.Distance between screw axis and hypoglossal canal was observed as (3.1 ± 1.1) mm.And the distance averaged (4.6 ± 1.4) mm between occipital condyle screw entry point and skull base and (6.1 ± 1.5) mm between entry point and inside edge of the occipital condyle.Conclusion Occipital condyle can be used as a new alternative fixed point in occipitocervical fusion.

Clinical application of flipping periosteum pedicle occipital outer plate for atlantoaxial fusion / 中华骨科杂志

Objective To evaluate the feasibility and efficacy of atlantoaxial fusion by flipping periosteum pedicle occipital outer plate.Methods Between March 2010 and June 2013,27 patients with atlantoaxial instability were treated by atlantoaxial fusion with flipping periosteum pedicle occipital outer plate and combining pedicle screws fixation.There were 16 males and 11 females with the age ranging from 23 to 56 years (with an average of 45.6 years) at time of surgery.There were 12 cases of fresh odontoid fracture with atlantoaxial instability,7 cases of old odontoid fracture combined with uneducable atlantoaxial dislocation,7 cases of congenital loose of odontoid process,and 1 case of rheumatoid arthritis.The visual analog scale (VAS) scores and Frankel grades were respectively used to evaluate the axial neck pain and the neurological deficit,and the results were compared before and after the operation.Bony fusion was observed by the midline sagittal CT scan images.Results All the patients were successfully operated.The operation time was 90 to 140 mins (with an average of 100 mins),and the blood loss was 100 to 600 ml (with an average of 160 ml).All patients were followed up for 18 to 39 months,with an average of 32.6 months.19 cases got solid fusion 3 months after surgery,and 7 cases got solid fusion 6 months after surgery,while 1 case got solid fusion 9 months after surgery.The average VAS score at final follow-up was 2.87± 1.03,which was significantly lower than that preoperatively 7.23± 1.65.Before the operation,nine cases presented spinal nerve function damage.At the final follow up time,7 cases returned to complete normal and 2 cases improved from grade C to grade D according to the Frankel classification.1 case was complicated with veiniplex injury with no heavy blood loss,due to successful hemostasia.Two screws were placed close to the vertebral artery canal,without clinical consequences.Conclusion The flipping periosteum pedicle occipital outer plate as a bone graft is one effective method for atlantoaxial fusion,which got great feasibility and safety.

Occipitalization of Atlas.

Occipitalization of atlas is an osseous anomaly of the craniovertebral junction which occurs at the base of the skull in the region of the foramen magnum. The knowledge of such a fusion is important because skeletal abnormalities at the craniocervical junction may result in sudden death. During bone cleaning procedure and routine undergraduate osteology teaching, three skulls with Occipitalization of atlas were encountered in the department of Anatomy atMMIMSR,Mullana, India. In one skull, both anterior and posterior archwere completely fused with occipital bone while the transverse process on the right side was not fused whereas left transverse process was fused with occipital bone. Both anterior and posterior arch were completely fused whereas transverse process on both sides were not fused in other skull. In another skull, partial and asymmetrical Occipitalization of atlas vertebra with occipital bone was found with bifid posterior arch of atlas at the level of posterior tubercle. Anterior arch was completely fused with basilar part of occipital bone but both the transverse processes were not fused. Reduced diameter of foramenmagnum due to the atlanto-occipital fusion might cause neurological complications due to compression of spinal cord or medulla oblongata, vertebral vessels, 1st cervical nerve, thus, knowledge of occipitalization of the atlas may be of substantial importance to orthopaedicians, neurosurgeons, physicians and radiologists dealing with abnormalities of the cervical spine.

Fratura de côndilos occipitais / Occipital condyles fractures

A fratura de côndilos occipitais é uma afecção considerada rara, mas que pode estar sendo subdiagnosticada. Fatores como a apresentação clínica variável, o exame físico frustro e a não identificação por radiografia simples dificultam esse diagnóstico, podendo levar a complicações como paralisia de nervos cranianos caudais e até mesmo a óbito. O presente estudo tem como objetivo revisar a literatura pertinente às fraturas de côndilos occipitais, com enfoque nas considerações anatômicas da junção craniocervical e ressaltando aspectos fisiopatológicos, parâmetros clínicos e as controvérsiasquanto ao tratamento. O incremento das técnicas radiológicas e a maior disponibilidade e uso de tomografia computadorizada possibilitaram o aumento do número de casos descritos dessas fraturas nas últimas décadas. A apresentação clínica é inespecífica e a tomografia da junção craniocervical é o método diagnóstico de escolha. A ausência de diagnóstico é responsável por sequelas, como déficits neurológicos, e foram descritas taxas de mortalidade de até 16% em casos de fraturas bilaterais. Omecanismo de injúria exato não é bem conhecido, mas a maioria dos autores indica a hiperextensão do pescoço associada à força vertical sobre a junção craniocervical. O tratamento é controverso, por causa da inconsistência nos resultados obtidos com o tratamento conservador baseado na classificação de Anderson e Montesano, em comparação com o escasso número de doentes tratados cirurgicamente.

The occipital condyle fractures are rare lesions, but they may have been under-diagnosed. Factors such as variable clinical presentation, inconclusive physical examination and no identification in the simple radiography difficult the diagnosis and may lead to complications such as paralysis of cranial nerves and death. This study aims to review the literature about occipital condyle fractures, emphasizing the anatomical considerations of the craniovertebral junction, pathophysiological view, clinical presentationand controversies regarding treatment. The improvement in radiological techniques and the increased availability and usage of computed tomography allowed the growth of reported cases of these fracturesin recent decades. The clinical presentation is nonspecific and CT of the craniocervical junction is the diagnostic method of choice. The absence of a diagnosis is responsible for sequel, such as neurologic deficits, and as mortality rates are of up to 16% in cases of bilateral fractures. The exact mechanism of injury is not well known, but most authors indicate the hyperextension of the neck associated with the vertical force on the craniocervical junction. The treatment is controversial due to the inconsistencies in the results obtained with conservative treatment based on the classification of Anderson and Montesano, compared to the small number of patients treated surgically.

Characterization of occipital condyle and comparison of its dimensions with head and foramen magnum circumferences in dry skulls of Iran / Caracterización del cóndilo occipital y comparación de sus dimensiones con la circunferencia de la cabeza y foramen magno en cráneos secos de Irán

The occipital condyle (OC) is an important area in craniovertebral surgery, but its anatomical features and the procedures concerning the OC have not been studied in detail yet. The aim of this study was to revisit the anatomy of the occipital condyle region and assess variations of the surrounding structures. Observations, on fifty dry skulls (dried specimens, 100 sides) and determined of condyle measurements. The mean length, width and height of occipital condyle were found to be 19.43±3.27 (right), 19.28±3.57 (left), 9.21±1.97 (right) 9.40±1.87 (left), 7.21±1.9 (right) and 7.33±2.74 mm (left), respectively. There were significant differences between right and left occipital condyles. The mean anterior intercondylar distance and posterior intercondylar distance were measured as 15.39±7 and 35.60±8.4 mm, respectively. Variations of occipital condyle shapes were kidney like (34.4%), S-like (25.6), triangular (13.3%) oval (10.0%), ring like (7.8%), eight like (6.7%) and deformed (2.2%) respectively. The condylar fossa presented in 60% of dry skull, 24% in right side and 36% in left side and also the condylar foramen was found in 60% of the specimens studied. There was no relation between the circumference of the head and the length of OC but we found relation between the circumference of the head and the width of OC (0.527) and foramen magnum circumference (0.433). The OC and FM are the main bony structures obstructing the surround of the brainstem. The differences in the size and the shape of occipital condyle have some differences and also similarities among racial subgroups. The posterior condylar vein may act asymmetrically. The correlation of the size of foramen magnum with the width of occipital condyles shows the importance of occipital condyle for lateral movements besides antero-posterior movements.

El cóndilo occipital (CO) es una estructura relevante en la cirugía craneovertebral, pero sus características anatómicas y procedimientos quirúrgicos relativos al CO no se han estudiado detalladamente. El objetivo fue revisar la anatomía de la región del CO y evaluar las variaciones de sus estructuras circundantes. Fueron observados 50 cráneos secos (100 lados) y se determinaron las mediciones del CO. La longitud media según lado fue 19,43±3,27 mm (derecho) y 19,28 ± 3,57 mm (izquierdo), el ancho medio fue 9,21±1,97 mm (derecho) y 9,40±1,87 mm (izquierda) y la altura media fue 7,21±1,9 mm (derecho) y 7,33±2,74 mm (izquierdo). Hubo diferencias significativas entre los CO derechos e izquierdos. La distancia intercondílea anterior y posterior media fue de 15,39±7 mm y 35,60±8,4 mm, respectivamente. La variación de formas del CO fue de riñon (34,4%), de S (25,6%), triangular (13,3%), oval (10,0%), de anillo (7,8%), de ocho (6,7%) y deformada (2,2%). La fosa condilar se observó en el 60% de los casos, 24% en lado derecho y 36% en el izquierdo; también el foramen condilar se encontró en el 60% de los casos. No se encontró relación entre la circunferencia de la cabeza y la longitud del CO, pero encontramos relación entre la circunferencia de la cabeza y el ancho del CO (0,527) y circunferencia del foramen magno (0,433). El CO y foramen magno son las principales estructuras óseas que constribuyen a rodear y proteger el tronco cerebral. Las diferencias en el tamaño y forma del CO tiene algunas diferencias y similitudes entre subgrupos raciales. La vena condilar posterior puede presentarse de manera asimétrica. La correlación del tamaño de foramen magno con el ancho de los CO muestra su relevancia en movimientos laterales y anteroposteriores.

Morphometric study of interparietal bone in Gujarat region.

Background: The occipital bone develops partly in cartilage and partly in membrane. The squamous part of occipital bone between two parietal bones occasionally presents a separate bones which are termed as inca, pre-interparietal bone or interparietal bone. Aims & Objective: (1) To determine the incidence of interparietal bone in skulls of Gujarat region. (2) To study different anomalies of interparietal bone and compare it with other studies. Material and Methods: Total 289 dried macerated skulls from Gujarat region were studied for incidence and type of interparietal bone anomaly. Results: Out of total 289 skulls interparietal bone was found in 23 bones giving incidence of 7.96%. Eight different varieties of interparietal bone anomalies were found and noted. Conclusion: Different anomalies of interparietal bone can be easily interpreted using the knowledge of ossification of interparietal part of occipital bone. Pre-interparietal bone is a misnomer and should not be reported separately.

A Study of Interparietal Bone in 105 Human Skulls of Gujarat Population.

Introduction : The squamous portion of the occipital bone consists of two different parts: the upper interparietal and the lower supraoccipital. The interparietal part may remain separated from the supraoccipital by a suture; it is then called the interparietal or Inca bone. Aim : In this study, incidence of interparietal bone has been estimated and compared with the other observations. Methodology : Total 105 cadaveric dry human skulls were examined to determine incidence of interparietal bone. Observations : The skulls which were observed, displayed many variations in the occipital region. In 7 cases, single or multiple separated bones were observed. In 4 cases (3.81%), the lower edge of these additional bones was situated above the external occipital protuberance and such bones could be classified as interparietal bones. In 3 cases (2.86%), the lower edge of these additional bones was much higher (between the lambda region and the highest nuchal line). The later can be classified as preinterparietal. Importance : Knowledge of interparietal bone is important for the radiologists, neurosurgeons, anthropologists, orthopedics and forensic experts to avoid misdiagnosis.

Interparietal bone variations in accordance with their ossification centres in human skulls / Variaciones de los huesos interparietales de acuerdo con sus centros de osificación en cráneos humanos

The upper interparietal segment of the squamous part of the occipital bone develops in membrane and the lower supraoccipital part develops in cartilage. According to the available literature, the interparietal segment is ossified from 2 to 3 pairs of ossification centres and each of these centres has 2 nuclei. Interparietal bone is formed due to failure of fusion of these centres and/or their nuclei with each other. Many variations of interparietal bone have been reported by many investigators. In the present study, out of 25 human skulls studied, six skulls had some interesting variations of interparietal bones. Four interparietal bones were found in one skull, 2 interparietal bones were observed in another skull and the remaining four skulls had a single interparietal (Os inca) bone at the lambda. In addition to interparietal bones, some sutural bones were also observed in three skulls. These variations were in accordance with the ossification centres of the membranous part of the occipital bone. By their location and shape it was concluded that they were formed due to failure of fusion of nuclei of the third pair centres of ossification with each other, with opposite fellow and with the second pair centers. It was further concluded that these cases of interparietal bones were different from what had been reported earlier by other researchers and this prompted the present report that may be found useful for anatomists, anthropologists, radiologists and neurosurgeons.

El segmento interparietal superior de la porción escamosa del hueso occipital es de origen membranoso y la parte inferior supraoccipital se desarrolla en el cartílago. De acuerdo con la literatura disponible, el segmento interparietal se osifica a partir de 2 a3 pares de centros y cada uno de estos centros cuenta con 2 núcleos. El hueso interparietal se forma debido a la falta de fusión de estos centros y / o sus núcleos. Muchas variaciones de hueso interparietal han sido reportados por investigadores. En el presente estudio, de 25 cráneos humanos estudiados, seis cráneos presentaban algunas variaciones interesantes de huesos interparietales. Cuatro huesos interparietales fueron encontrados en un cráneo, dos huesos interparietales en un cráneo y cuatro cráneos presentaban un solo hueso interparietal (Os inca) en el lambda. Además, de los huesos interparietales, en tres cráneos se observaron huesos suturales. Estas variaciones estaban en relación con los centros de osificación de la parte membranosa del hueso occipital. Por su ubicación y forma, se concluyó que los huesos se formaron debido a la falta de fusión entre sí de los núcleos de los centros del tercer par de osificación, con otros opuestos y con los centros del segundo par. Se concluye, además, que estos casos de huesos interparietales eran diferentes de lo que se había informado anteriormente por otros investigadores y esto nos impulsó al estudio, el cual puede ser útil para anatomistas, antropólogos, radiólogos y neurocirujanos.

Three-dimensional CT features of occipital squama normal anatomy, anatomic variations and fractures / 中华放射学杂志

Objective To evaluate 3D CT features of normal anatomy,anatomic variations and fractures of occipital squama.Methods The 3D CT features on MIP,VR images were analyzed retrospectively in 589 pediatric cases.The normal anatomy,anatomic variations and fractures of occipital squama were observed respectively,and the differential diagnostic features including the individual location,appearance and extension were analyzed.Results Four hundred and thirty-three patients (75.2％) showed normal anatomy,including 154 patients with adult occipital anatomical features,279 patients with posterior intraoccipital synchondrosis,and 37 patients with Kerckring-supraoccipital synchondrosis.When cases with recent trauma history were excluded,113 patients (19.1％) showed anatomic variants,including unpenetrating sutures and penetrating sutures.The former could be subdivided to Mendosal sutures in 23 cases,superior median fissures in 19 cases,and midline supraoccipital fissures in 4 cases,while the latter could be subdivided to the interparietal bone variations in 54 cases,wormian bones in 23 cases,and accessory bones in 7 cases.Two or more variations coexisted in 33 cases.The occipital squama fractures were shown in 34 cases (5.6％),including linear fractures in 27 cases,comminuted fractures in 3 cases,with depression fracture in one case,separation of cranial sutures in 3 cases,and other fractures associated with variants in 3 cases.The fractures were sharp,or jagged,without limitation of the occification.Conclusion There are different 3D CT features of normal anatomy,anatomic variations and fractures of occipital squama in children,which are important for making the accurate diagnosis.

Fraturas do côndilo occipital: atualização da experiência em nosso serviço e revisão da literatura / Fractures of the occipital condyle: updated experience in our service and literature review / Fracturas del cóndilo occipital: actualización de la experiencia en nuestro servicio y revisión de la literatura

Apresentamos neste trabalho a casuística de fraturas de côndilo occipital diagnosticada e tratada em nosso serviço nos últimos 10 anos. O presente estudo dá continuidade ao levantamento epidemiológico já realizado no período de 1993 a 2000. No período de 2001 a 2011, foram diagnosticados seis casos de fraturas de côndilo occipital e todos eles foram tratados de forma conservadora, exceto um, no qual se colocou um halo craniano inicialmente. Nos cinco casos tratados de modo conservador, observaram-se bons resultados, com estabilidade do segmento nas radiografias funcionais, ausência de limitação de movimento e ausência de dor. O paciente que foi tratado com halo apresentava tetraplegia parcial FRANKEL C e fraturas associadas (C5, C6, L1 e L2) e não apresentou melhora do quadro neurológico, verificando-se limitação do movimento cervical. Destacamos ainda a importância da investigação ativa de lesões na transição occipitocervical, principalmente nos casos decorrentes de trauma de alta energia, pois além das implicações clínicas da detecção precoce da fratura, o melhor emprego dos exames subsidiários tem sido um fator relevante para o aumento da incidência de fraturas do côndilo occipital. Como é historicamente relatado, o tratamento conservador ainda é eficaz e com baixo índice de complicações, e o tratamento cirúrgico deve ser indicado em casos com instabilidade definida.

We present a series of occipital condyle fractures diagnosed and treated in our hospital during the past 10 years. The present study continues an epidemiologic survey already performed in the period 1993-2000. From 2001 to 2011, six cases of fracture of the occipital condyle were diagnosed and all of them were treated conservatively, except one, in which a halo was initially placed. In the five cases treated conservatively, there were good results, with stable segment in functional radiographs, absence of limitation of motion and no pain. The patient treated with halo had FRANKEL C partial quadriplegia and associated fractures (C5, C6, L1, and L2), showing no neurological improvement, besides observing cervical motion limitation. We also highlight the importance of active research on lesions in the occipital-cervical transition, particularly in cases resulting from high-energy trauma, because in addition to the clinical implications of early detection of fracture, the best use of ancillary tests have been an important factor for the increased incidence of fractures of the occipital condyle. As is historically reported, conservative treatment is still effective and has a low rate of complications, and surgical treatment should be indicated in cases with established instability.

Presentamos en este trabajo la casuística de fracturas de cóndilo occipital diagnosticada y tratada en nuestro servicio en los últimos 10 años. El presente estudio le da continuidad al levantamiento epidemiológico ya realizado en el período de 1993 a 2000. En el período de 2001 a 2011, fueron diagnosticados seis casos de fracturas de cóndilo occipital y todos ellos fueron tratados de forma conservadora, excepto uno, en el cual se colocó un halo craneano inicialmente. En los cinco casos tratados de modo conservador, se observaron buenos resultados, con estabilidad del segmento en las radiografías funcionales, ausencia de limitación de movimiento y ausencia de dolor. El paciente que fue tratado con halo presentaba tetraplejía parcial FRANKEL C y fracturas asociadas (C5, C6, L1 y L2) y no presentó mejora del cuadro neurológico, verificándose limitación del movimiento cervical. Destacamos además la importancia de la investigación activa de lesiones en la transición occipitocervical, principalmente en los casos provenientes de trauma de alta energía, pues además de las implicaciones clínicas de la detección precoz de la fractura, el mejor empleo de los exámenes subsidiarios ha sido un factor relevante para el aumento de la incidencia de fracturas del cóndilo occipital. Como es históricamente relatado, el tratamiento conservador aún es eficaz y con bajo índice de complicaciones, y el tratamiento quirúrgico debe ser indicado en casos con inestabilidad definida.

Morphology and morphometry of the foramen magnum in Toy Poodle and Yorkshire terrier dogs / Morfologia e morfometria do forame magno em cães das raças Poodle Toy e Yorkshire terrier

The occipital dysplasia has been characterized by a dorsal enlargement of the foramen magnum which can vary in size and shape. Clinical signs may be present or not in animals with occipital dysplasia. The purpose of this study was to radiographically analyze the morphology and morphometry of the foramen magnum of thirty healthy dogs. This study chose to use fifteen Yorkshire terrier dogs and fifteen Toy Poodle dogs in order to characterize the radiographic aspects of the foramen magnum and contribute to the diagnosis and critical analysis of the occipital dysplasia importance. According to the foramen magnum morphology and tracings, it was possible to classify the radiographic aspects into different shapes varing from oval and quadrangular. Out of 26 (86.7 percent) animals had a dorsal enlargement and 4 (13.3 percent) showed normal foramen magnum. Animals without any clinical signs that are radiographically classified as dysplastic dogs may simply represent an anatomic variation of the foramen magnum.

A displasia do occipital é o alargamento dorsal do forame magno, o qual pode variar a sua forma e tamanho e os animais com esta alteração morfológica podem ou não apresentar manifestações clínicas. O objetivo desta pesquisa foi avaliar radiograficamente a morfologia e a morfometria do forame magno de 30 cães assintomáticos das raças Poodle toy e Yorkshire terrier, sendo 15 de cada, a fim de se caracterizar os aspectos radiográficos do forame magno e contribuir para o diagnóstico e análise crítica da relevância da displasia do occipital. O forame magno apresentou aspectos que variaram de oval a quadrangular. A presença do alargamento dorsal ocorreu em 26 (86,7 por cento) animais e a ausência em apenas quatro (13,3 por cento). Animais sem manifestações clínicas, que apresentam graus variados de alargamento dorsal e são classificados radiograficamente como displásicos, podem apenas representar variações anatômicas do forame magno.