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1.
Eur. j. anat ; 24(5): 439-448, sept. 2020. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-195281

RESUMO

The aim of this study is to describe the anatomical alterations in complementary tests (MRI and EMG) in patients with cervicobrachialgia according to sex and age. Retrospective study of 184 patients with cervicobrachialgia who underwent cervical MRI and EMG. The variables analyzed were gender, age, elements of spondylosis (osteophytes, arthropathy, spondylolisthesis and canal stenosis), the type of disc disease (protrusion and herniated disc) and curvature in the sagittal plane. The EMG was used to evaluate the neurogenic findings in the muscles dependent on the spinal roots of C4 to C8-T1.Average age was 53.65±11.96 years. The patients were evaluated for the presence of osteophytes (n = 111), arthropathy (n = 76), spondylolisthesis (n = 15) and stenosis of the spinal canal (n = 35). The highest incidences were osteophytes in C5-C6 (n = 108), protrusions in C5-C6 (n = 58), herniated disc in C5-C6 (n=18) and neurogenic findings in C7 (n = 130). The rectification of cervical lordosis appeared in 124 patients.S pondylosis increases with age. Disc herniations, disc protrusions and motor radiculopathy are more frequent in the 5th to 6th years of life. In patients with cervicobrachialgia, the sagittal rectification is more common than the normal lordosis


No disponible


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Espondilose/diagnóstico por imagem , Coluna Vertebral/anatomia & histologia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/patologia , Estudos Retrospectivos , Radiculopatia/diagnóstico por imagem
2.
Nature ; 581(7806): 67-70, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32376955

RESUMO

In recent decades, intensive research on non-avian dinosaurs has strongly suggested that these animals were restricted to terrestrial environments1. Historical proposals that some groups, such as sauropods and hadrosaurs, lived in aquatic environments2,3 were abandoned decades ago4-6. It has recently been argued that at least some of the spinosaurids-an unusual group of large-bodied theropods of the Cretaceous era-were semi-aquatic7,8, but this idea has been challenged on anatomical, biomechanical and taphonomic grounds, and remains controversial9-11. Here we present unambiguous evidence for an aquatic propulsive structure in a dinosaur, the giant theropod Spinosaurus aegyptiacus7,12. This dinosaur has a tail with an unexpected and unique shape that consists of extremely tall neural spines and elongate chevrons, which forms a large, flexible fin-like organ capable of extensive lateral excursion. Using a robotic flapping apparatus to measure undulatory forces in physical models of different tail shapes, we show that the tail shape of Spinosaurus produces greater thrust and efficiency in water than the tail shapes of terrestrial dinosaurs and that these measures of performance are more comparable to those of extant aquatic vertebrates that use vertically expanded tails to generate forward propulsion while swimming. These results are consistent with the suite of adaptations for an aquatic lifestyle and piscivorous diet that have previously been documented for Spinosaurus7,13,14. Although developed to a lesser degree, aquatic adaptations are also found in other members of the spinosaurid clade15,16, which had a near-global distribution and a stratigraphic range of more than 50 million years14, pointing to a substantial invasion of aquatic environments by dinosaurs.


Assuntos
Dinossauros/anatomia & histologia , Dinossauros/fisiologia , Natação , Cauda/anatomia & histologia , Cauda/fisiologia , Água , Adaptação Fisiológica , Animais , Organismos Aquáticos/classificação , Organismos Aquáticos/fisiologia , Dieta/veterinária , Dinossauros/classificação , Ecossistema , Peixes , Robótica , Coluna Vertebral/anatomia & histologia
3.
Eur. j. anat ; 24(3): 205-210, mayo 2020. tab, graf
Artigo em Inglês | IBECS | ID: ibc-191469

RESUMO

Proper coordination and function of muscles is required to move and stabilize the spine. However, due to difficulty in sampling, few empirical data exist regarding the specific structural and architectural characteristics of spine muscles in humans. The use of animal models is an alternative; but comparisons between animal and human spine muscles are lacking. Therefore, ten adult male Sprague-Dawley rats were euthanized, skinned and immersion-fixed in formalin; six rats in a neutral spine position and four rats in a fully flexed spine position. Longissimus, iliocostalis and multifidus muscles were excised, individual fascicles were dissected and sarcomere lengths were measured via laser diffraction. Results demonstrat-ed that mean sarcomere lengths in the neutral position were 2.29 μm, 2.44 μm and 2.44 μm for the multifidus, longissimus and iliocostalis, respecti-vely. In the fully flexed posture, sarcomeres were lengthened to 2.79 μm, 2.92 μm and 2.91 μm, respectively. In the neutral spine posture, these mus-cles were closer to optimal length compared to those previously measured in humans. In the fullyflexed posture, these muscles exhibited similar relative lengths (on the descending limb of the force-length relationship) compared to those previously modeled in humans. In summary, rat spine extensor muscles have longer sarcomeres, relative to optimal length, in the neutral posture compared to human spine extensor muscles. However, in the fully flexed spine position, both rat and human spine muscles act on the descending limb of the force-length relationship, all at similar relative lengths. These data provide a context to guide the use of rat spine muscles as a model to understand structural and functional characteristics in the human


No disponible


Assuntos
Humanos , Animais , Masculino , Ratos , Vértebras Lombares/anatomia & histologia , Sarcômeros , Músculo Esquelético/anatomia & histologia , Modelos Animais , Coluna Vertebral/anatomia & histologia , Ratos Sprague-Dawley , Cadáver
4.
PLoS One ; 15(4): e0231544, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32320430

RESUMO

Due to their cartilaginous endoskeleton and the continuous tooth replacement, the chondrichthyan fossil record predominantly consists of isolated teeth, which offer diagnostic features for taxonomic identifications, but only provide very limited information of an organism's life history. In contrast, the calcified vertebral centra of elasmobranchs (sharks, skates and rays) yield important information about ecological and biological traits that can be utilized for constructing age-structured population dynamic models of extant species and palaeoecological reconstructions of such aspects in extinct groups. Here, we describe two large shark vertebrae from the Santonian (Upper Cretaceous) of Spain, which show a unique combination of characters (asterospondylic calcification pattern, with concentric lamellae and numerous parallel bands that are oriented perpendicular) that is only known from ptychodontid sharks, a distinct, extinct group of giant durophagous sharks of the Cretaceous era. Based on linear regression models for large extant sharks a total length between 430 and 707cm was estimated for the examined specimen. Our results indicate that ptychodontid sharks were large viviparous animals, with slow growth rates, matured very late and, therefore, show typical traits for K-selected species. These traits combined with a highly specialized feeding ecology might have played a crucial role for the success but also, eventually, extinction of this group.


Assuntos
Fósseis , Tubarões/anatomia & histologia , Tubarões/crescimento & desenvolvimento , Animais , Tamanho Corporal , Calcificação Fisiológica , Extinção Biológica , Comportamento Alimentar , Espanha , Coluna Vertebral/anatomia & histologia , Viviparidade não Mamífera
5.
Sci Rep ; 10(1): 7184, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32346053

RESUMO

The early Permian mesosaurs were the first amniotes to re-invade aquatic environments. One of their most controversial and puzzling features is their distinctive caudal anatomy, which has been suggested as a mechanism to facilitate caudal autotomy. Several researchers have described putative fracture planes in mesosaur caudal vertebrae - unossified regions in the middle of caudal vertebral centra - that in many extant squamates allow the tail to separate and the animal to escape predation. However, the reports of fracture planes in mesosaurs have never been closely investigated beyond preliminary descriptions, which has prompted scepticism. Here, using numerous vertebral series, histology, and X-ray computed tomography, we provide a detailed account of fracture planes in all three species of mesosaurs. Given the importance of the tail for propulsion in many other aquatic reptiles, the identification of fracture planes in mesosaurs has important implications for their aquatic locomotion. Despite mesosaurs apparently having the ability to autotomize their tail, it is unlikely that they actually made use of this behaviour due to a lack of predation pressure and no record of autotomized tails in articulated specimens. We suggest that the presence of fracture planes in mesosaurs is an evolutionary relic and could represent a synapomorphy for an as-yet undetermined terrestrial clade of Palaeozoic amniotes that includes the earliest radiation of secondarily aquatic tetrapods.


Assuntos
Dinossauros/anatomia & histologia , Coluna Vertebral/anatomia & histologia , Animais , Cauda/anatomia & histologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-32260344

RESUMO

The sagittal spinal morphology presents 4 physiological curvatures that increase endurance to axial compression forces and allow adequate postural balance. These curves must remain within normal ranges to achieve a static and dynamic balance, a correct functioning of the muscles and an adequate distribution of the loads, and thus minimize the injury risk. The purpose of this study was to categorize the sagittal spinal alignment according to the different morphotypes obtained for each curve in standing, slump sitting, and trunk forward bending positions in schoolchildren. It was a cross-sectional study. Sagittal spinal curvatures were assessed in 731 students from 16 elementary schools. In the sagittal standing position assessment, 70.45% and 89.06% of schoolchildren presented a "normal" morphotype for both dorsal and lumbar curves, respectively. After the application of the "Sagittal Integral Morphotype" protocol according to the morphotypes obtained in the three positions assessment (standing, slump sitting, and trunk forward bending), it was observed how the frequency of normal morphotypes for the dorsal and lumbar curve decreased considerably (only 32% and 6.6% of children obtained a "normal sagittal integral morphotype" for the thoracic and lumbar curvatures, respectively). These results show how it is necessary to include the slump sitting and trunk forward bending assessment as part of the protocol to define the "integral" sagittal alignment of the spine and establish a correct diagnosis. The use of the diagnostic classification presented in this study will allow early detection of misalignment not identified with the assessment of standing position.


Assuntos
Equilíbrio Postural , Postura , Coluna Vertebral , Criança , Estudos Transversais , Humanos , Vértebras Lombares , Espanha , Coluna Vertebral/anatomia & histologia
7.
Int. j. morphol ; 38(2): 415-422, abr. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1056456

RESUMO

This study aimed to investigate the sagittal spinal-pelvic morphological changes, as well as the relationship between pelvic anatomical changes and the spinal-pelvic plane in patients with adolescent idiopathic scoliosis (AIS), in order to provide guidelines for orthopedic surgery in AIS. X-ray data were collected for retrospective analysis from 30 patients diagnosed as AIS in the Departments of Radiology at the Second Affiliated Hospital of Inner Mongolia Medical University and the Inner Mongolia International Mongolian Medical Hospital from April 2014 to November 2018, along with 30 normal adolescents as control. Pelvic parameters, including pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS), a spinal parameter, lumbar lordosis (LL), and anatomical parameters, including sacral width (SW) and femoral head- sacrum distance (FH-S), were measured. The spinal-pelvic parameters were compared between AIS patients and normal controls and also between male and female AIS patients. Pearson correlation was performed to analyze correlation between spinal-pelvic parameters and between spinal-pelvic parameters and anatomical parameters in both AIS patients and normal controls. PT was significantly lower in AIS patients than in normal controls (P < 0.05), whereas no significant difference was found in the other spinal-pelvic parameters, i. e. , LL, PI, and SS. There was a significant difference in PT between sexes in AIS patients. SS was significantly correlated with LL in EIA patients (P < 0.05, r > 0.5). SS was significantly correlated with LL and PI, and PT with LL, PI, and SS in normal controls (all P < 0.05), and there was no significant correlation between the other sagittal spinal-pelvic parameters (P > 0.05). FH-S was significantly correlated with LL, PI, SS, and PT in AIS patients (all P < 0.05). AIS affects some of the sagittal spinalpelvic parameters and anatomical parameters. In AIS, there is a significant correlation between the spinal-pelvic parameters, and the anatomical parameter is significantly correlated with multiple spinal-pelvic parameters.


Este estudio tuvo como objetivo investigar los cambios morfológicos sagitales de la columna vertebral-pélvica, así como la relación entre los cambios anatómicos pélvicos y el plano espinal-pélvico en pacientes con escoliosis idiopática adolescente (EIA), con el fin de proporcionar pautas para la cirugía ortopédica en AIS. Se obtuvieron los datos de rayos X para el análisis retrospectivo de 30 pacientes diagnosticados como EIA en los Departamentos de Radiología del hospital Second Affiliated Hospital of Inner Mongolia Medical University y el hospital Inner Mongolia International Mongolian Medical Hospital, desde abril de 2014 hasta noviembre del 2018, junto con 30 adolescentes normales como control. Se midieron los parámetros pélvicos, que incluyeron incidencia pélvica (IP), inclinación pélvica (P) y pendiente sacra (PS), un parámetro espinal, lordosis lumbar (LL) y parámetros anatómicos, que incluyeron el ancho sacro (AS) y la distancia del sacro cabeza femoral (FH-S). Los parámetros espinalpélvicos se compararon entre los pacientes con EIA y los controles normales, como también entre pacientes con EIA masculinos y femeninos. La correlación de Pearson se realizó para analizar la correlación entre los parámetros espinal-pélvicos y entre los parámetros espinal-pélvicos y los parámetros anatómicos tanto en pacientes con EIA como en controles normales. PT fue significativamente menor en pacientes con EIA que en los controles normales (P <0,05), mientras que no se encontraron diferencias significativas en los otros parámetros espinal-pélvicos, i. mi. , LL, PI y SS. Hubo una diferencia significativa en PT en pacientes de ambos sexos con EIA. SS se correlacionó significativamente con LL en pacientes con EIA (P <0,05, r> 0,5). SS se correlacionó significativamente con LL y PI, y PT con LL, PI y SS en controles normales (todos P <0,05), y no hubo correlación significativa entre los otros parámetros sagitales de la columna vertebral-pélvica (P> 0,05) FH-S se correlacionó significativamente con LL, PI, SS y PT en pacientes con EIA (todos P <0,05). EIA afecta algunos de los parámetros sagitales de la columna vertebral-pélvica y los parámetros anatómicos. En EIA, existe una correlación significativa entre los parámetros espinal-pélvicos, y el parámetro anatómico se correlaciona significativamente con múltiples parámetros espinales-pélvicos.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Ossos Pélvicos/anatomia & histologia , Escoliose/patologia , Coluna Vertebral/anatomia & histologia
8.
Anat Sci Int ; 95(3): 387-398, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32125674

RESUMO

In many mammals, gender and skull shape are related to the bone morphology of the entire body; however, this has not been well established in the domestic cat (Felis catus). This study aims to find a relationship between cervical, thoracic and lumbar vertebrae morphometrics with regard to the sex and skull shape of domestic cats. A total of 79 samples obtained from 92 dried bones of domestic cats were used to determine morphometric measurements for a total of 29 parameters. Hierarchical clustering was used to cluster the vertebral bones found in three groups: C3-T1, T2-T11 and T12-L7. The skull shape identification process employed discriminative analysis and revealed the highest training data accuracy rate at up to 86.20% in T4 followed by L1 (86.04%) Axis (85.71%) and C5 (85.18%). Sex identification employed discriminative analysis and displayed the highest training data accuracy rate at up to 75.58% in L1 followed by, T7 (71.87%) and C6 (71.79%). Moreover, we found that 14% of the samples had one vertebra missing (T13 or L1). In conclusion, domestic cat vertebral morphometrics were found to be more related to skull shape than gender. In addition, bone clustering employed morphometric data and yielded a result that was similar to that of traditional cluster analysis involving body regions.


Assuntos
Anatomia/métodos , Gatos/anatomia & histologia , Caracteres Sexuais , Crânio/anatomia & histologia , Coluna Vertebral/anatomia & histologia , Animais
9.
Sci Rep ; 10(1): 2733, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066790

RESUMO

The Batrachosauroididae are an enigmatic group of salamanders known from the Cretaceous and Tertiary of North America and Europe. In Europe, the family is known only by two species of the genus Palaeoproteus. The genus has limited distribution in Western and Central Europe. In the present paper, we describe a new species, Palaeoproteus miocenicus, from the early late Miocene (11-9 Ma) of Austria and Ukraine, representing the youngest record of the family Batrachosauroididae from the Neogene of Europe. The new species differs from the Paleogene representatives of the genus by 12 characters, including large body size, the long anterior extension of the Meckelian groove and the size and shape of the odontoid process on the dentary. The µCT scanning of bones of the new species revealed novel features (e.g. anterior extension of Meckelian groove, interconnected network of canals and small cavities in atlas) observable only in this species. P. miocenicus inhabited aquatic environments, which existed under wet climatic conditions with mean annual precipitation higher than 900 mm. The new species expands the temporal range of the genus by at least 30 million years and enlarges the palaeogeographic distribution of the genus into Eastern Europe.


Assuntos
Fósseis/história , Arcada Osseodentária/anatomia & histologia , Coluna Vertebral/anatomia & histologia , Urodelos/classificação , Animais , Áustria , Evolução Biológica , Tamanho Corporal , Extinção Biológica , História Antiga , Arcada Osseodentária/fisiologia , Filogenia , Coluna Vertebral/fisiologia , Ucrânia , Urodelos/anatomia & histologia , Urodelos/fisiologia
10.
Rev. bras. ortop ; 55(1): 62-69, Jan.-Feb. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1092668

RESUMO

Abstract Objective To determine the anatomical parameters of the atlas (C1) in a sample of the Brazilian population and compare them with the results already presented in the literature for other populations and, thus, to identify and change the indications of implants used in the treatment of the upper cervical spine. Methods We performed a retrospective observational study of a prospective database, including 100 patients seen between January 2012 and December 2013. We used axial and sagittal sections of computed tomography (CT) scans. The parameters studied were; axial: distance from posterior tubercle to the screw entry point (DPT_EP), safety angle of the axial screw (SA_AS), ideal axial screw length (_ASL) and distance of the spinal canal from the transverse foramen (DSC_TF); Sagittal: ideal sagittal screw length (_SSL), safety angle of the sagittal screw (SA_SS) and posterior arch thickness (_PAT). All of the parameters were divided according to age, gender, and left and right sides. Results The minimum mean point of entry ranged from 20 mm to 22.7 mm. The average security zone ranged from 18.09º to 23.68º. The mean posterior arch thickness ranged from 7.21 mm to 8.95 mm. The lowest averages were found in females. Using an original and reproducible technique of CT evaluation. Conclusion The anatomical parameters of the atlas found in the sample of the studied population were similar to those previously presented in the literature. However, differences between the sexes were observed.


Resumo Objetivo Determinar os parâmetros anatômicos do atlas (C1) em uma amostra da população brasileira, compará-los aos resultados já apresentados na literatura para outras populações e, assim, identificar e alterar as indicações dos implantes utilizados no tratamento das afecções da coluna cervical alta. Métodos Foi realizado um estudo observacional retrospectivo de um banco de dados prospectivo, incluindo 100 pacientes atendidos entre janeiro de 2012 a dezembro de 2013. Foram utilizados cortes axiais e sagitais de tomografias computadorizadas (TCs). Os parâmetros estudados foram; axial: ponto de entrada do parafuso (DTPPE), ângulo de segurança (ADSPA), tamanho ideal do parafuso (TPA) e tamanho da massa lateral entre os forames vertebral e transverso (DCVFT); sagital: tamanho ideal do parafuso (TPS), ângulo de segurança (ADSPS) e espessura do arco posterior (EAP). Todos os parâmetros foram divididos de acordo com a idade, gênero e lado esquerdo e direito. Resultados A média mínima do ponto de entrada variou de 20 mm a 22,7 mm. A zona de segurança média variou de 18,09º a 23,68º. A espessura média do arco posterior variou entre 7,21 mm e 8,95 mm. As menores médias foram encontradas no sexo feminino. Por meio de uma técnica original e reprodutível de avaliação de TC. Conclusão Os parâmetros anatômicos do atlas encontrados na amostra da população estudada foram semelhantes aos apresentados previamente na literatura. No entanto, foram observadas diferenças entre os sexos.


Assuntos
Coluna Vertebral/anatomia & histologia , Tomografia , Tomografia Computadorizada por Raios X , Atlas
11.
Homo ; 71(1): 37-42, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-31939993

RESUMO

Anatomical stature estimation methods reconstruct stature for skeletal specimens by adding up the heights of skeletal elements contributing to stature. In addition, these estimations factor in a certain amount of soft tissue known as "soft tissue correction". Our study focuses on the relationship between living stature and one of the major soft tissue contributors to stature: the intervertebral disc thickness/height. The purpose of this study was to clarify whether intervertebral disc thickness is greater in tall individuals and whether there is a linear correlation between stature and intervertebral disc height. To conduct this study, we utilized a subsample of the Northern Finland Birth Cohort of 1966 (n = 12,058) with known stature. We measured vertebral heights and intervertebral disc heights from low back MRI examination performed at the age of 46 years (n = 200). All subjects were considered healthy with no spinal injuries or pathologies. Our results clearly indicate that stature and intervertebral disc height have positive, statistically significant association. According to our results it is advisable to take into account the individual's skeletal height when soft tissue corrections for anatomical stature estimations are performed. Further studies utilizing full body MRI are needed to produce more accurate soft tissue corrections.


Assuntos
Antropologia Física/métodos , Estatura/fisiologia , Disco Intervertebral/anatomia & histologia , Coluna Vertebral/anatomia & histologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Spine (Phila Pa 1976) ; 45(2): 79-87, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31899690

RESUMO

STUDY DESIGN: A cross-sectional radiographic study. OBJECTIVE: The aim of this study was to establish the age- and sex-related normative values of whole-body sagittal alignment in asymptomatic Chinese adult population, and to investigate the changes and possible associated compensation mechanisms across age groups. SUMMARY OF BACKGROUND DATA: Previous studies have reported normative data for sagittal spinal alignment in asymptomatic adults. However, there was a lack of comprehensive investigation on age- and sex-related normative values of whole-body sagittal alignment. METHODS: A total of 584 asymptomatic Chinese adults aged 20 to 89 years were recruited. Subjects were grouped according to age and sex. Whole-body standing radiographs were acquired for evaluating sagittal alignment from spine to lower limb. Comparisons of sagittal parameters between sex in different age groups were performed by independent t test. Pearson correlation analysis was used to determine relationships between each parameter. RESULTS: Mean values of each sagittal parameter were presented based on age and sex. Thoracic kyphosis showed steady increasing trend while lumbar lordosis gradual decrease in both sexes. Pelvic tilt (PT) in males is greater than in females across all age groups with age-related gradual increase. There were significant differences between males and females from 20 to 60 years in terms of KneeFlex angle (KA) and AnkleFlex angle, but the differences were not significant after 60s. T1 pelvic angle (TPA) was significantly correlated with spinal, pelvic and lower-limb alignment. The older group (≥50 years) had a stronger correlation of TPA with PT and KA, whereas the younger (<50 years) had stronger correlation with TK. CONCLUSION: This study presented a comprehensive study of whole-body sagittal alignment based on a large asymptomatic population, which could serve as an age- and sex-specific reference value for spine surgeons when planning for correction surgery. Age can influence the recruitment of compensation mechanism that involves more pelvic and lower limb mechanisms for elderly people. LEVEL OF EVIDENCE: 3.


Assuntos
Distinções e Prêmios , Coluna Vertebral/anatomia & histologia , Coluna Vertebral/diagnóstico por imagem , Imagem Corporal Total , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Grupo com Ancestrais do Continente Asiático , Estudos Transversais , Feminino , Humanos , Cifose/diagnóstico por imagem , Lordose/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Ossos Pélvicos/diagnóstico por imagem , Estudos Prospectivos , Radiografia , Valores de Referência , Fatores Sexuais , Posição Ortostática , Adulto Jovem
14.
Eur. j. anat ; 24(1): 9-15, ene. 2020. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-186060

RESUMO

The aim of the present study was to study the dimensions of various parts of the typical cervical vertebrae in anatomical samples. This study included 100 cadaveric dried typical cervical vertebrae, which were obtained at the osteology sec-tion. This study lacks the information on sex and chronological number of cervical vertebrae being studied. The dimensions of different parts of vertebrae like the body, pedicle, spinous process, laminae and articular facets were measured. The data of the right and left sides were statistically analysed by using the software 'EZR' (version 1.38, 2019). The shapes of the superior and inferi-or articular facets were macroscopically observed. The mean height of the typical cervical vertebra was 10.92 ± 1.35 mm; the vertebral body antero-posterior length was 14.79 ± 1.96 mm and 15.56 ± 1.95 mm at the superior and inferior borders; the vertebral body transverse length was 23.22 ± 2.16 mm and 19.88 ± 2.38 mm at the superior and inferior borders respectively; the spinous process length was 15.25 ± 4.25 mm; the vertebral fora-men anteroposterior and transverse length were 12.33 ± 1.68 mm and 21.98 ± 1.82 mm respectively. The pedicle length was more (p > 0.05) at the right side than the left. In the remaining parameters of the paired structures, there was no statistically significant difference observed (p < 0.05). The morphometric data of the present study will enlighten the operating spine surgeon during procedures like internal fixation and decom-pression procedures of fracture spine. We believe that the surgical implants should be devised as per the morphometric data of the particular population


No disponible


Assuntos
Humanos , Vértebras Cervicais/anatomia & histologia , Cadáver , Coluna Vertebral/anatomia & histologia , Osteologia
15.
Neurosurg Rev ; 43(4): 1135-1142, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31270704

RESUMO

Cortical bone trajectory (CBT) can facilitate both minimum invasiveness and strong screw fixation; however, ensuring the ideal cortical trajectory is challenging due to the narrow corridor, necessitating high-level surgical skill. A patient-specific template guide for CBT screw placement may be a promising solution to improve accuracy and safety. Little has been reported on the use of a CBT screw guide in clinical practice. The aim of the present study was to evaluate the accuracy of CBT screw placement using the template guide. This study was a retrospective clinical evaluation of prospectively collected patients. Forty-three consecutively enrolled patients who underwent posterior lumbar spinal fusion using the guide system were included. First, three-dimensional planning of CBT screw placement was performed using computer simulation software. The trajectory was directed in a more anterior position of the vertebral body, compared with the original CBT, and the standard size was set as 5-6 mm in diameter and 40-45 mm in length. Then, screw guides were created for each vertebra preoperatively and used. The safety and accuracy of a total of 198 inserted screws (L1 to L5) were analyzed using postoperative computed tomography by evaluation of pedicle perforation and measurement of screw deviations between the planned and actual screw positions. A total of 193 screws (97.5%) were placed completely inside the pedicle and there was no incidence of neurovascular injuries. The mean screw deviation from the planned trajectory on the coronal plane at the midpoint of the pedicle was 0.62 ± 0.42 mm, and the mean angular deviations in the sagittal and transverse planes were 1.68 ± 1.24° and 1.27 ± 0.77°, respectively. CBT screw placement using a patient-specific template guide was accurate enough for clinical application. This technique could be an effective solution to achieve both correct screw insertion and a reduction of complications.


Assuntos
Parafusos Ósseos , Osso Cortical/anatomia & histologia , Osso Cortical/cirurgia , Coluna Vertebral/anatomia & histologia , Coluna Vertebral/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Parafusos Ósseos/efeitos adversos , Simulação por Computador , Feminino , Humanos , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Estudos Retrospectivos , Fusão Vertebral , Tomografia Computadorizada por Raios X , Resultado do Tratamento
16.
Am J Phys Anthropol ; 171(1): 17-36, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31675109

RESUMO

OBJECTIVES: The main objective is to quantify integration, modularity, and response to selection in the presacral vertebral column of modern humans. MATERIALS AND METHODS: Seventeen linear variables on each presacral vertebra were collected in 108 modern humans producing a total of ~39,000 measurements. Then, we studied patterns and magnitudes of integration at regional, vertebral, and intra-vertebral levels. Additionally, we calculated the ability of vertebrae to respond to selection by quantifying differences in evolvability, flexibility, and constraint throughout the spine. RESULTS: The results indicate that caudal vertebrae are more evolvable than those located more cranially in the presacral vertebral column, following an increasing pattern of evolvability from the cervical to the lumbar region. Additionally, the atlas and fifth lumbar vertebra show the lowest values of integration, while central thoracic vertebrae display the highest magnitudes of integration. DISCUSSION: These results could be related to three main factors: body plan organization expressed by the Hox genes, the strong developmental constraints that determine the number of mammalian vertebrae, and, finally, the functional requirements of an adaptation to bipedal locomotion in the human lineage.


Assuntos
Evolução Biológica , Seleção Genética , Coluna Vertebral/anatomia & histologia , Feminino , Humanos , Masculino
17.
J Fish Biol ; 96(2): 378-393, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31750931

RESUMO

Using morphometric, meristic and qualitative characters, we confirmed a specific status of a clade discovered based on molecular data only. The newly described species Phoxinus krkae has a very local distribution in the upper Krka River but is easily morphologically distinguished from geographically neighbouring species with much wider ranges: Phoxinus lumaireul, Phoxinus marsilii and Phoxinus csikii. Phoxinus krkae is well differentiated in statistical analyses and differs from other species of Phoxinus in northern Adriatic Sea drainages and right-bank tributaries of the middle and lower River Danube by a combination of characters, none of them unique: caudal peduncle length 1.9-2.2 times minimum depth of caudal peduncle; upper lip not projecting beyond lower lip; rostral fold absent; total number of scales in lateral series 74-84; lateral line incomplete and interrupted, commonly 17-49 (< 60% of total number of scales in lateral series) with no or few canal segments on posterior body and caudal peduncle; scales on belly extending forward to over middle of distance between pelvic-fin base and pectoral-fin origin; patches of breast scales commonly connected by scattered scales or forming 1-3 regular rows of scales; total vertebrae commonly 38-39 (22 + 17, 22 + 16 or 21 + 17). The study reveals unrecognised morphological diversity within the group and provides the groundwork for future taxonomic study in Phoxinus in the Adriatic region and the Danube Basin.


Assuntos
Cyprinidae/anatomia & histologia , Cyprinidae/classificação , Nadadeiras de Animais/anatomia & histologia , Escamas de Animais/anatomia & histologia , Animais , Croácia , Cyprinidae/genética , Análise Discriminante , Feminino , Masculino , Rios , Caracteres Sexuais , Pele/anatomia & histologia , Coluna Vertebral/anatomia & histologia
18.
J Morphol ; 281(2): 229-239, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31883141

RESUMO

Chameleons (Chamaeleonidae) are known for their arboreal lifestyle, in which they make use of their prehensile tail. Yet, some species have a more terrestrial lifestyle, such as Brookesia and Rieppeleon species, as well as some chameleons of the genera Chamaeleo and Bradypodion. The main goal of this study was to identify the key anatomical features of the tail vertebral morphology associated with prehensile capacity. Both interspecific and intra-individual variation in skeletal tail morphology was investigated. For this, a 3D-shape analysis was performed on vertebral morphology using µCT-images of different species of prehensile and nonprehensile tailed chameleons. A difference in overall tail size and caudal vertebral morphology does exist between prehensile and nonprehensile taxa. Nonprehensile tailed species have a shorter tail with fewer vertebrae, a generally shorter neural spine and shorter transverse processes that are positioned more anteriorly (with respect to the vertebral center). The longer tails of prehensile species have more vertebrae as well as an increased length of the processes, likely providing a greater area for muscle attachment. At the intra-individual level, regional variation is observed with more robust proximal tail vertebrae having longer processes. The distal part has relatively longer vertebrae with shorter processes. Although longer, the small size and high number of the distal vertebrae allows the tail to coil around perches.


Assuntos
Ecossistema , Lagartos/anatomia & histologia , Coluna Vertebral/anatomia & histologia , Cauda/anatomia & histologia , Pontos de Referência Anatômicos , Animais , Análise Discriminante , Músculos/anatomia & histologia , Filogenia , Análise de Componente Principal
19.
Spine (Phila Pa 1976) ; 45(1): 38-47, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31425432

RESUMO

STUDY DESIGN: Retrospective. OBJECTIVE: To evaluate the image quality of low-radiation-dose computed tomography (LD-CT) of the thoracolumbar spine, using model-based iterative reconstruction (MBIR) for measuring pedicle diameter. SUMMARY OF BACKGROUND DATA: MBIR can drastically reduce radiation dose but its utility in spine surgery planning is unknown. METHODS: We identified patients (mean age, 70.5 ±â€Š13.3 yrs) who incidentally underwent both standard-radiation-dose CT (SD-CT) with hybrid iterative reconstruction and LD-CT with MBIR of the thoracolumbar spine within 2 years. We compared radiation dose, subjective image sharpness, signal-to-noise ratio, and contrast-to-noise ratio for the two tests. Additionally, inner pedicle diameters were measured on SD-CT (DSD) and LD-CT (DLD), and statistically compared. RESULTS: We included 24 CT and 84 pedicles for each CT group. The radiation dose of LD-CT estimated by volume CT dose index was 1.21 ±â€Š0.42 mGy, one-sixth the dose of SD-CT. The effective dose of LD-CT was 0.58 ±â€Š0.31 mSv, equivalent to or less than that of a one-time lumbar X-ray in a previous report. LD-CT was significantly inferior in subjective image sharpness for the contour of vertebrae and trabecular structure, but superior for signal-to-noise ratio and contrast-to-noise ratio. The intra-rater reliability (intra-RR) and inter-RR for DLD were 0.985 and 0.892, respectively, comparable to those of DSD. DLD was consistently 0.30 mm smaller than DSD when compared within the same pedicle, regardless of pedicle diameter. CONCLUSION: LD-CT with MBIR produced a radiation dose equivalent to a one-time lumbar X-ray and provided excellent images for measuring pedicle diameter. LD-CT can be a substitute for SD-CT when planning spine surgery if the relationship between DSD and DLD is sufficiently understood. LEVEL OF EVIDENCE: 3.


Assuntos
Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Reprodutibilidade dos Testes , Estudos Retrospectivos , Razão Sinal-Ruído , Coluna Vertebral/anatomia & histologia , Raios X
20.
PLoS One ; 14(12): e0225391, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31825956

RESUMO

Aegicetus gehennae is a new African protocetid whale based on a partial skull with much of an associated postcranial skeleton. The type specimen, Egyptian Geological Museum, Cairo [CGM] 60584, was found near the base of the early-Priabonian-age (earliest late Eocene) Gehannam Formation of the Wadi Al Hitan World Heritage Site in Egypt. The cranium is distinctive in having ventrally-deflected exoccipitals. The vertebral column is complete from cervical C1 through caudal Ca9, with a vertebral formula of 7:15:4:4:9+, representing, respectively, the number of cervical, thoracic, lumbar, sacral, and caudal vertebrae. CGM 60584 has two more rib-bearing thoracic vertebrae than other known protocetids, and two fewer lumbars. Sacral centra are unfused, and there is no defined auricular surface on the ilium. Thus there was no weight-bearing sacroiliac joint. The sternum is distinctive in being exceptionally broad and flat. The body weight of CGM 60584, a putative male, is estimated to have been about 890 kg in life. Long bones of the fore and hind limbs are shorter than expected for a protocetid of this size. Bones of the manus are similar in length and more robust compared to those of the pes. A log vertebral length profile for CGM 60584 parallels that of middle Eocene Maiacetus inuus through the anterior and middle thorax, but more posterior vertebrae are proportionally longer. Vertebral elongation, loss of a sacroiliac articulation, and hind limb reduction indicate that Aegicetus gehennae was more fully aquatic and less specialized as a foot-powered swimmer than earlier protocetids. It is doubtful that A. gehennae had a tail fluke, and the caudal flattening known for basilosaurids is shorter relative to vertebral column length than flattening associated with a fluke in any modern whale. Late protocetids and basilosaurids had relatively long skeletons, longer than those known earlier and later, and the middle-to-late Eocene transition from foot-powered to tail-powered swimming seemingly involved some form of mid-body-and-tail undulation.


Assuntos
Cetáceos , Natação/fisiologia , Cauda/anatomia & histologia , Cauda/fisiologia , Animais , Evolução Biológica , Egito , Fósseis , Crânio/anatomia & histologia , Coluna Vertebral/anatomia & histologia , Baleias
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