Esqueleto axial y apendicular de vertebrado / Axial and appendicular skeleton of vertebrates

Los primeros componentes de las vértebras fueron los arcos dorsales (neural e interneural) y ventrales (hemal e interhemal) que se apoyaban en la notocorda; el siguiente paso fue la formación de dos centros (intercentro y pleurocentro), que sirvieron para fijar y dar soporte a los arcos. Muchos peces presentan costillas dorsales y ventrales. En las aves se reducen las costillas cervicales y se fusionan a las vértebras, las primeras costillas torácicas son flotantes y la mayoría de las verdaderas presentan procesos que permiten la fijación muscular y refuerzan las paredes torácicas. Los mamíferos presentan costillas en todas las vértebras torácicas, siendo la mayoría verdaderas. El esternón es una estructura de origen endocondral, los peces, tortugas, serpientes y muchos lagartos apodos, carecen de esternón. Las aves voladoras tienen un gran esternón provisto de una prominente quilla ventral. Desarrollo del esqueleto axial: La notocorda y la parte ventral del tubo neural expresan Sonic hedgehog (SHH), que induce a la porción ventromedial del somita a transformarse en esclerotomo y a expresar el factor de transcripción PAX-1, que controla la formación de cartílago y hueso para que se constituyan las vértebras. El patrón de expresión de los genes Hox en vertebrados, es quien determina cuál es el tipo de estructura vertebral que se tiene que formar. El esqueleto apendicular comprende la cintura pectoral formada por elementos esqueléticos dérmicos y endocondrales, que sostiene la aleta pectoral y la cintura pélvica o caderas, formada sólo por elementos endocondrales, que sostienen la aleta pelviana. Los miembros anteriores y posteriores de los tetrápodos están construidos bajo el mismo patrón, diferenciándose tres regiones: autopodio, zeugopodio y estilopodio. Desarrollo del esqueleto apendicular: Se forma desde el mesodermo lateral somático y la cresta apical ectodérmica...

The first components of the dorsal vertebrae, were arches (neural and interneural) and ventral (haemal and interhemal) that relied on the notochord, the next step was the formation of two centers (intercentro and pleurocentro), which served to fix and support the arches. Many fish have dorsal and ventral ribs. In birds cervical ribs are reduced and vertebrae are fused, the first thoracic ribs are floating and the majority present processes allowing muscle fixation and reinforce the chest wall. Mammals have ribs on all thoracic vertebrae, the majority are true. The sternum is a structure of endochondral origin, fish, turtles, snakes and lizards have no sternum. Airborne fowl are provided with a large sternum prominent ventral keel. Development of the axial skeleton: The notochord and ventral neural tube express Sonic hedgehog (SHH) that induces the ventromedial portion of somite to become sclerotome and express the transcription factor Pax-1, which controls the formation of cartilage and bone that constitute the vertebrae. The expression pattern of Hox genes in vertebrates is what determines which type of vertebral structure is to be formed. The appendicular skeleton comprises the pectoral girdle consists of dermal and endochondral skeletal elements, holding the pectoral fin and pelvic girdle, consisting only endochondral elements that sustain pelvic fin. The forelimbs and hindlimbs of tetrapods are built on the same pattern, differing in three regions: autopod, zeugopod and stylopod. Appendicular skeletal development: Is formed from somatic lateral mesoderm and the apical ectodermal ridge...

Sex determination from sternal end of 4th rib in Western U.P. population: An autopsy study.

There have been several studies on the human skull, long bones, pelvis, sacrum and manubrium to establish the sex of skeletal remains. If small segment of the bone or small bone is found then it will be very difficult to identify the sex. The present study showed the sternal extremity of the fourth rib can be used in determining the sex by direct metrical analysis of an isolated 4th rib. The samples (55 males, 39 females) were obtained from individual of known age and sex and three measurements (SI, APW and PD) were taken from each rib. The sample was divided into five groups from less than 15 years to more than 60 years and was analysed by stepwise discriminant function analysis. It was found the specificity of sex determination varied from 50 % to 88.89 % and overall correct classification varied from 60% to 94%. SI was the most reliable followed by APW and APW measurement is most useful criteria for more than 60 year of age. It was therefore concluded that sexual dimorphism can be detected by direct measurement of fourth rib and this dimorphism increases with age.

Esqueletogênese dos ossos da coluna vertebral, costelas e esqueleto abdominal em embriões de Caiman Yacare (Daudin, 1802) (Crocodylia: Alligatoridae) / Skeletogenesis of the vertebral column bones, ribs and inscriptional ribs in embryos of Caiman yacare (Crocodylia: Alligaroridae)

Dentre os répteis, os lagartos e os testudines são o foco de inúmeras investigações que contemplam o estudo de sua ontogenia, contudo, descrições do desenvolvimento e da sequência de ossificação em crocodilianos são escassas. Assim, objetivou-se investigar o padrão de formação e a sequência de ossificação das vértebras e costelas em Caiman yacare (DAUDIN, 1802). Embriões foram coletados em intervalos regulares e submetidos ao protocolo de diafanização e coloração por Aliarina red S. O processo de ossificação da coluna vertebral ocorre no sentido crânio-caudal a partir dos 33 dias. As vértebras se formam a partir de centros de ossificação distintos para os centros, o arco e as apófises. O pró-atlas se forma a partir de dois centros de ossificação distintos que se fundem até o fim do período de incubação. A fusão dorsal dos processos transversos ocorre parcialmente aos 51 dias, dando origem ao diminuto esboço do processo espinhoso. No embrião de 57 dias a articulação entre as costelas, o sacral e o ílio não estava evidente. A morfologia e tamanho das vértebras caudais variam consideravelmente no sentido crânio-caudal. Todas apresentam os processos hemais e iniciam sua ossificação até os 48 dias. C. yacare apresenta um número variado de costelas abdominais, que se ossificam ainda durante o período embrionário. O padrão da esqueletogênese de C. yacare é congruente com de outros répteis, embora existam algumas variações, com particular ênfase na remodelação de estruturas, o que possivelmente reflete as variações do período de incubação entre os diversos répteis relatados.

Among reptiles, lizards and Testudines are the focus of numerous investigations that include the study of its ontogeny, however, descriptions of development and ossification sequence in crocodilians are scarce. Thus, it was aimed to investigate the pattern of training and sequence of ossification of the vertebrae and ribs in Caiman yacare (Daudin, 1802). Embryos were collected at regular intervals and submitted to the protocol of clearing and staining Aliarina red S. The process of ossification of the vertebral column occurs in the craniocaudal direction from the 33 days. The vertebrae are formed from separate ossification centers for the centers, the arch and the transverse processes. The proatlas is formed from two separate ossification centers that fuse to the end of the incubation period. The fusion of dorsal transverse process is partly to 51 days, giving rise to a small sketch of the spinous process. In the embryo of 57 days the link between the ribs, the sacrum and the ilium was not evident. The morphology and size of caudal vertebrae vary considerably in the craniocaudal direction. All have the hemal processes and initiate its ossification up to 48 days. C. yacare has a varied number of abdominal ribs, which ossify even during the embryonic period. The pattern of skeletogenesis C. yacare is consistent with other reptiles, although some variations, with particular emphasis on the remodeling of structures, which possibly reflects the variations in incubation period among the various reptiles reported.

Anatomical Study of Position of the Rib Head for Placing Anterior Vertebral Body Screws in a Chinese Population / Estudio Anatómico de la Posición de la Cabeza de la Costilla para Colocar Tornillos en la Zona Anterior del Cuerpo Vertebral en una Población China

Instrumentation of anterior vertebral body screws has become an important approach for treatment of unstable fracture or curvature of the spine, but little attention has been paid to the starting point of placing the screws and variability of the rib head position. We analyzed the variability of rib head position in a Chinese population in terms of the spinal canal and vertebral body using computed tomography (CT). Images from transverse CT scan of the T4-T12 vertebral bodies of 30 normal individuals were 3D reconstructed, and analyzed for measurement of parameters, which included: 1) distance between the left (or right) anterior border of the rib head and the posterior (or anterior) margin of the vertebral body [L(R )ARHP(A)VB], 2) left (or right) transverse dimension [L(R)TD], 3) left (or right) posterior (or anterior) safe angle [L(R)P(A)SA], and 4) distance between the inferior border of the left (or right) rib head and the superior (or inferior) end-plate in the sagittal plane [IL(R)RHS(I)EP]. The ARHPVB, PSA, and IRHIEP gradually decrease, but ARHAVB, TD, ASA, and IRHSEP gradually increase from T4 to T12, indicating that the position of the rib head changes from a more anterior position to a more posterior position and from a more superior position to a more inferior position as the number of the vertebra increases. Our study has provided comprehensive reference guide for accurate and safe instrumentation of vertebral body screws in treating related spine diseases.

La instrumentación del cuerpo anterior vertebral con tornillos ha sido una vía importante para el tratamiento de las fracturas inestables y curvaturas de la columna, pero se ha prestado poca atención a la zona de colocación de los tornillos y la variabilidad de la posición de la cabeza costal. Se analizó la variabilidad de la posición de la cabeza de la costilla en una población de China en relación al canal vertebral y cuerpo vertebral mediante tomografía computarizada (TC). Imágenes de cortes transversales de TC correspondientes a los cuerpos vertebrales T4-T12 de 30 individuos normales fueron reconstruidos tridimensionalmente, y se analizó la medida de algunos parámetros: 1) la distancia entre el margen anterior izquierdo (o derecho) de la cabeza de la costilla y el margen posterior (o anterior) del cuerpo vertebral [L(R)ARHP(A)VB], 2) Dimensión transversa izquierda (o derecha) [L(R)TD], 3) ángulo de seguridad izquierdo (o derecho) posterior (o anterior) [L(R)P(A)SA], y 4) la distancia entre el margen inferior de la cabeza de la costilla izquierda (o derecha) y la placa terminal superior (o inferior) en el plano sagital [IL(R)RHS(I)EP]. El ARHPVB, PSA, y IRHIEP disminuyeron gradualmente, pero ARHAVB, TD, ASA, y IRHSEP aumentaron gradualmente de T4 a T12, lo que indica que la posición de la cabeza de la costilla cambia desde una posición más anterior a una posición más posterior y de una posición más superior a una posición más inferior a medida que aumenta el número de vértebras. Nuestro estudio ha proporcionado completa guía de referencia para la instrumentación precisa y segura de tornillos en el cuerpo vertebral para el tratamiento de enfermedades relacionadas con la columna vertebral.

Notes on the axial skeleton of the titanosaur Bonitasaura salgadoi (Dinosauria-Sauropoda)

Sauropod axial anatomy is particularly important in understanding morphological features and phylogenetic analyses. Spatial arrangement of zygapophyses and rib articulations, as well as their complex laminar development, help to recognize the relative position of isolated vertebral elements. The presence of anterior, mid and posterior elements along the cervical, dorsal and caudal series in Bonitasaura salgadoi allows the analysis of several anatomical characteristics. These include the pattern of neurocentral closure with unfused, partially fused and completely fused elements in a peculiar temporal sequence, as well as several neural spine modifications and the laminar arrangement. The variations in neural spine morphology include a lateral expansion of the distal tip in cervico-dorsal region, different lateral constituents of these lateral expansions, and a marked deviation in spine angulation. The spinal inclination allows the division into three easily recognizable vertebral regions separated by two landmarks, which adds support in the determination of an accurate vertebral position for isolated elements. Finally, an analysis of the vertebral laminae reveals the importance of examining vertebral series in order to recognize laminar homologies and developmental series. Two vertebral laminae are analyzed here.

A anatomia axial dos saurópodes compõe um conjunto dedados fundamentais para a caracterização morfológica dostáxons, bem como para a determinação de suas relações filogenéticas. A disposição espacial das zigapófises e articulações das costelas, assim como de seu complexo de lâminas acessórias, auxiliam no reconhecimento da posição relativa de elementos vertebrais isolados. A preservação de vértebras anteriores, médias e posteriores nas séries cervical, dorsal e caudal de Bonitasaura salgadoi permite a análise de características adicionais diagnósticas observadas ao longo das séries vertebrais. Estas incluem o grau de fusão da sutura neurocentral,havendo elementos livres, parcialmente fundidos a completamente fundidos em uma sequência temporal peculiar, assim como a presença de diversas modificações do espinho neural e a disposição laminar. As variações na morfologia do espinho neural incluem uma expansão lateral em seu ápice distal na região cervico-dorsal, outros componentes laterais distintos destas expansões, e um desvio crânio-caudal marcado pela angulação do espinho neural. A inclinação espinal permite a divisão em três segmentos vertebrais reconhecíveis separados por duas linhas de transição. Finalmente, a análise das lâminas vertebrais revela a importância de examinar a série vertebral a fim de reconhecer homologias nas lâminas e nas séries de desenvolvimento. Neste trabalho são analisadas duas lâminas vertebrais.

Subclavius posticus muscle: a case report

A rare case of subclavius posticus muscle observed in a male cadaver is reported here. Presence of such accessory muscles have been recognized as possible causes of neurovascular compression syndromes in this region. It has been suggested by several authors that presence of accessory muscles like subclavius posticus can be a potential cause of thoracic outlet syndrome.

Es reportado un caso raro de músculo subclavio posticus observado en un cadáver de sexo masculino. La presencia de tales músculos accesorios ha sido reconocida como posible causa de los síndromes de compresión neurovascular en esta región. Varios autores han sugerido que la presencia de músculos accesorios como subclavio posticus, puede ser una causa potencial del síndrome de salida torácica.

Age determination from sternal ends of the ribs- an autopsy study.

A random study of 500 cases for age determination from sternal ends of the ribs was carried out in the Department of Forensic Medicine and Toxicology, Govt. Medical College, Amritsar with joint supervision of Department of Anatomy. The aim of the study was to determine the age after death with minimal error. Currently there are different parameters available to determine the age of a person like study of teeth, ossification of bones and other ancillary data, but the accurate reliability of these measures is only limited to a particular age group i.e. 25± 5 years. For the age beyond this, many workers in different parts of the world have done their studies to accurately determine the age of a person from the skeleton. Study by Iscan et al (1984) has emphasized fair amount of accurate assessment of age from the sternal end of the ribs. The present study was a similar attempt to analyze the reliability and accuracy of Iscan et al’s (1984) work in this part of the world.

Estudo anátomo-cirúrgico do cólon transverso do eqüino por acesso paralombar esquerdo / Anatomic and surgical study of the equine transverse colon from left paralombar aprouch

O cólon transverso é um estreitamento do canal alimentar, sujeito a sofrer processos obstrutivos. A ampliação do conhecimento sobre essa estrutura e adjacentes é de grande importância cirúrgica. Neste estudo foram utilizados 10 cadáveres de eqüinos de diferentes raças, idades e sexos, divididos em dois grupos de cinco. No primeiro grupo foi realizada uma incisão no 16º espaço intercostal esquerdo e posterior ressecção da 16ª costela. No segundo grupo a incisão foi feita sobre a 17ª costela com a remoção da mesma. Todas as estruturas identificadas foram registradas em fichas individuais, assim como a extensão exteriorizada do cólon transverso. Em todas os animais o cólon transverso foi totalmente visualizado e parcialmente exteriorizado, sendo que houve melhor manipulação e exteriorização no segundo grupo, além da maior facilidade no emprego da técnica, com a incisão sobre a costela a ser ressecada. Dessa forma, concluímos que o cólon transverso pode ser acessado pela fossa paralombar esquerda, sendo que a remoção da 17ª costela proporciona o melhor acesso para essa estrutura.

The transverse colon is a constriction of the bowel lumen, which canbe submitted to obstructive process. The knowledge enlargement about this structure and the adjacent ones has a great surgical importance. For such study, ten anatomic pieces, from equines corpses of different breed, age and sex, were used and divided in two groups. In the first group an incision was made in the left 16 intercostal space and farther resection of the 16 rib. In the second group an incision was made over the 17 rib, before its ressection. All the identified structures were registered into individual files, such as the extension of the exteriorized portion. In all of the studied pieces, the transverse colon was entirely visualized and partially exteriorized. However, we had better handling and exteriorization in the second group, as well as we noticed its technique was of easier execution. In accordance with the results, through this work is possible to conclude that the transverse colon can be approached by the left flank, and that the removal of the 17 rib provides a better access to the transverse colon.

The scalene tubercle.

One hundred and thirty right and 114 left first ribs from a random collection have been studied for the characters of the scalene tubercle and the related structures. The tubercle is not always present but the muscular impression for the insertion of the scalenus anterior muscle on the superior surface of the first rib is almost constant and it generally extends upto the medial third of this surface. The arterial groove, generally shallow, lies behind the tubercle or the muscular impression and generally extends only upto the medial 2/3 of the superior surface. Likewise, the venous groove, mostly shallow, lies in front of the tubercle or the muscular impression and extends, generally, only upto the medial 2/3 of the surface. Normally, there is no separate groove for the lower trunk of the brachial plexus.