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Concept: Cervical vertebrae

180

We present here evidence for an early Holocene case of decapitation in the New World (Burial 26), found in the rock shelter of Lapa do Santo in 2007. Lapa do Santo is an archaeological site located in the Lagoa Santa karst in east-central Brazil with evidence of human occupation dating as far back as 11.7-12.7 cal kyBP (95.4% interval). An ultra-filtered AMS age determination on a fragment of the sphenoid provided an age range of 9.1-9.4 cal kyBP (95.4% interval) for Burial 26. The interment was composed of an articulated cranium, mandible and first six cervical vertebrae. Cut marks with a v-shaped profile were observed in the mandible and sixth cervical vertebra. The right hand was amputated and laid over the left side of the face with distal phalanges pointing to the chin and the left hand was amputated and laid over the right side of the face with distal phalanges pointing to the forehead. Strontium analysis comparing Burial 26’s isotopic signature to other specimens from Lapa do Santo suggests this was a local member of the group. Therefore, we suggest a ritualized decapitation instead of trophy-taking, testifying for the sophistication of mortuary rituals among hunter-gatherers in the Americas during the early Archaic period. In the apparent absence of wealth goods or elaborated architecture, Lapa do Santo’s inhabitants seemed to use the human body to express their cosmological principles regarding death.

Concepts: Cervical vertebrae

166

Azhdarchid pterosaurs include the largest animals to ever take to the skies with some species exceeding 10 metres in wingspan and 220 kg in mass. Associated skeletons show that azhdarchids were long-necked, long-jawed predators that combined a wing planform suited for soaring with limb adaptations indicative of quadrupedal terrestrial foraging. The postcranial proportions of the group have been regarded as uniform overall, irrespective of their overall size, notwithstanding suggestions that minor variation may have been present. Here, we discuss a recently discovered giant azhdarchid neck vertebra referable to Hatzegopteryx from the Maastrichtian Sebeş Formation of the Transylvanian Basin, Romania, which shows how some azhdarchids departed markedly from conventional views on their proportions. This vertebra, which we consider a cervical VII, is 240 mm long as preserved and almost as wide. Among azhdarchid cervicals, it is remarkable for the thickness of its cortex (4-6 mm along its ventral wall) and robust proportions. By comparing its dimensions to other giant azhdarchid cervicals and to the more completely known necks of smaller taxa, we argue that Hatzegopteryx had a proportionally short, stocky neck highly resistant to torsion and compression. This specimen is one of several hinting at greater disparity within Azhdarchidae than previously considered, but is the first to demonstrate such proportional differences within giant taxa. On the assumption that other aspects of Hatzegopteryx functional anatomy were similar to those of other azhdarchids, and with reference to the absence of large terrestrial predators in the Maastrichtian of Transylvania, we suggest that this pterosaur played a dominant predatory role among the unusual palaeofauna of ancient Haţeg.

Concepts: Vertebra, Pterosaur, Pterodactyloidea, Azhdarchidae, Cervical vertebrae, Neck, Quetzalcoatlus, Hatzegopteryx

82

Increased excavation of dinosaurs from China over the last two decades has enriched the record of Asian titanosauriform sauropods. However, the relationships of these sauropods remain contentious, and hinges on a few well-preserved taxa, such as Euhelopus zdanskyi. Here we describe a new sauropod, Yongjinglong datangi gen. nov. et sp. nov., from the Lower Cretaceous Hekou Group in the Lanzhou Basin of Gansu Province, northwestern China. Yongjinglong datangi is characterized by the following unique combination of characters, including seven autapomorphies: long-crowned, spoon-shaped premaxillary tooth; axially elongate parapophyses on the cervical vertebra; very deep lateral pneumatic foramina on the lateral surfaces of the cervical and cranial dorsal vertebral centra; low, unbifurcated neural spine fused with the postzygapophyses to form a cranially-pointing, triangular plate in a middle dorsal vertebra; an “XI”-shaped configuration of the laminae on the arches of the middle dorsal vertebrae; a very long scapular blade with straight cranial and caudal edges; and a tall, deep groove on the lateral surface of the distal shaft of the radius. The new specimen shares several features with other sauropods: a pronounced M. triceps longus tubercle on the scapula and ventrolaterally elongated parapophyses in its cervical vertebra as in Euhelopodidae. Based on phylogenetic analyses Yongjinglong datangi is highly derived within Titanosauria, which suggests either a remarkable convergence with more basal titanosauriform sauropods in the Early Cretaceous or a retention of plesiomorphic features that were lost in other titanosaurians. The morphology and remarkable length of the scapulocoracoid reveal an unusual relationship between the shoulder and the middle trunk: the scapulocoracoid spans over half of the length of the trunk. The medial, notch-shaped coracoid foramen and the partially fused scapulocoracoid synostosis suggest that the specimen is a subadult individual. This specimen sheds new light on the diversity of Early Cretaceous Titanosauriformes in China.

Concepts: Vertebral column, Vertebra, Cretaceous, Cervical vertebrae, Sauropoda, Dinosaur, Titanosaur, Euhelopus

75

A new oviraptorid dinosaur from the Late Cretaceous of Ganzhou, bringing oviraptrotid diversity of this region to seven taxa, is described. It is characterized by a distinct cassowary-like crest on the skull, no pleurocoels on the centra from the second through fourth cervical vertebrae, a neck twice as long as the dorsal vertebral column and slightly longer than the forelimb (including the manus). Phylogenetic analysis recovers the new oviraptorid taxon, Corythoraptor jacobsi, as closely related to Huanansaurus from Ganzhou. Osteochronology suggests that the type specimen of Corythoraptor had not reached stationary growth stage but died while decreasing growth rates. The histology implies that it would correspond to an immature individual approximately eight years old. We hypothesize, based on the inner structure compared to that in modern cassowaries, that the prominent casque of Corythoraptor was a multifunction-structure utilized in display, communication and probably expression of the fitness during mating seasons.

Concepts: Biology, Vertebral column, Skull, Vertebra, Cervical vertebrae, Dinosaur, Botanical nomenclature

72

Spinal immobilisation during extrication of patients in road traffic collisions is routinely used despite the lack of evidence for this practice. In a previous proof of concept study (n=1), we recorded up to four times more cervical spine movement during extrication using conventional techniques than self-controlled extrication.

Concepts: Lumbar vertebrae, Vertebral column, Cervical vertebrae, Thoracic vertebrae, Road transport, Road accidents, Car safety

59

Diplodocids are among the best known sauropod dinosaurs. Numerous specimens of currently 15 accepted species belonging to ten genera have been reported from the Late Jurassic to Early Cretaceous of North and South America, Europe, and Africa. The highest diversity is known from the Upper Jurassic Morrison Formation of the western United States: a recent review recognized 12 valid, named species, and possibly three additional, yet unnamed ones. One of these is herein described in detail and referred to the genus Galeamopus. The holotype specimen of Galeamopus pabsti sp. nov., SMA 0011, is represented by material from all body parts but the tail, and was found at the Howe-Scott Quarry in the northern Bighorn Basin in Wyoming, USA. Autapomorphic features of the new species include a horizontal canal on the maxilla that connects the posterior margin of the preantorbital and the ventral margin of the antorbital fenestrae, a vertical midline groove marking the sagittal nuchal crest, the presence of a large foramen connecting the postzygapophyseal centrodiapophyseal fossa and the spinopostzygapophyseal fossa of mid- and posterior cervical vertebrae, a very robust humerus, a laterally placed, rugose tubercle on the concave proximal portion of the anterior surface of the humerus, a relatively stout radius, the absence of a distinct ambiens process on the pubis, and a distinctly concave posteroventral margin of the ascending process of the astragalus. In addition to the holotype specimen SMA 0011, the skull USNM 2673 can also be referred to Galeamopus pabsti. Histology shows that the type specimen SMA 0011 is sexually mature, although neurocentral closure was not completed at the time of death. Because SMA 0011 has highly pneumatized cervical vertebrae, the development of the lamination appears a more important indicator for individual age than neurocentral fusion patterns. SMA 0011 is one of very few sauropod specimens that preserves the cervico-dorsal transition in both vertebrae and ribs. The association of ribs with their respective vertebrae shows that the transition between cervical and dorsal vertebrae is significantly different in Galeamopus pabsti than in Diplodocus carnegii or Apatosaurus louisae, being represented by a considerable shortening of the centra from the last cervical to the first dorsal vertebra. Diplodocids show a surprisingly high diversity in the Morrison Formation. This can possibly be explained by a combination of geographical and temporal segregation, and niche partitioning.

Concepts: Cervical vertebrae, Dinosaur, Diplodocus, Supersaurus, Jurassic, Brachiosaurus, Camarasaurus, Allosaurus

43

Canine Chiari-like malformation (CM) is a complex abnormality of the skull and craniocervical junction associated with miniaturization and brachycephaly which can result in the spinal cord disease syringomyelia (SM). This study investigated the inheritance of CM in a Griffon Bruxellois (GB) family and feasibility of crossbreeding a brachycephalic CM affected GB with a mesaticephalic normal Australian terrier and then backcrossing to produce individuals free of the malformation and regain GB breed characteristics. The study family cohort (n = 27) included five founder dogs from a previous baseline study of 155 GB which defined CM as a global malformation of the cranium and craniocervical junction with a shortened skull base and increased proximity of the cervical vertebrae to the skull. T1-weighted sagittal DICOM images of the brain and craniocervical junction were analysed for five significant traits (two angles, three lines) identified from the previous study and subsequent Qualitative Trait Loci analysis. Mean measurements for mixed breed, pure-breed and baseline study groups were compared. Results indicated that mixed breed traits posed less risk for CM and SM and were useful to distinguish the phenotype. Moreover on the MR images, the filial relationships displayed by the traits exhibited segregation and those presenting the greatest risk for CM appeared additive towards the severity of the condition. The external phenotypes revealed that by outcrossing breed types and with careful selection of appropriate conformation characteristics in the first generation, it is possible to regain the GB breed standard and reduce the degree of CM. The four GB affected with SM in the study all exhibited reduced caudal skull development compared to their relatives. The craniocervical traits may be useful for quantifying CM and assessing the possibility of SM thus assisting breeders with mate selection. However, such a system requires validation to ensure appropriateness for all breeds at risk.

Concepts: Spinal cord, Skull, Vertebra, Selective breeding, Breed, Cervical vertebrae, Meninges, Trait

40

Mammals as a rule have seven cervical vertebrae, a number that remains remarkably constant. Changes of this number are associated with major congenital abnormalities (pleiotropic effects) that are, at least in humans, strongly selected against. Recently, it was found that Late Pleistocene mammoths (Mammuthus primigenius) from the North Sea have an unusually high incidence of abnormal cervical vertebral numbers, approximately ten times higher than that of extant elephants. Abnormal numbers were due to the presence of large cervical ribs on the seventh vertebra, indicating a homeotic change from a cervical rib-less vertebra into a thoracic rib-bearing vertebra. The high incidence of cervical ribs indicates a vulnerable condition and is thought to be due to inbreeding and adverse conditions that may have impacted early pregnancies in declining populations. In this study we investigated the incidence of cervical ribs in another extinct Late Pleistocene megaherbivore from the North Sea and the Netherlands, the woolly rhinoceros (Coelodonta antiquitatis). We show that the incidence of abnormal cervical vertebral numbers in the woolly rhinoceros is unusually high for mammals (15,6%, n = 32) and much higher than in extant Rhinoceratidae (0%, n = 56). This indicates that woolly rhinoceros lived under vulnerable conditions, just like woolly mammoths. The vulnerable condition may well have contributed to their eventual extinction.

Concepts: Vertebra, Extinction, Cervical vertebrae, Rhinoceros, Megafauna, Mammoth, Woolly mammoth, Pleistocene megafauna

40

Study Design Literature review. Objective The aim of this literature review was to detail the effects of smoking in spine surgery and examine whether perioperative smoking cessation could mitigate these risks. Methods A review of the relevant literature examining the effects of smoking and cessation on surgery was conducted using PubMed, Google Scholar, and Cochrane databases. Results Current smokers are significantly more likely to experience pseudarthrosis and postoperative infection and to report lower clinical outcomes after surgery in both the cervical and lumbar spines. Smoking cessation can reduce the risks of these complications depending on both the duration and timing of tobacco abstinence. Conclusion Smoking negatively affects both the objective and subjective outcomes of surgery in the lumbar and cervical spine. Current literature supports smoking cessation as an effective tool in potentially mitigating these unwanted outcomes. Future investigations in this field should be directed toward developing a better understanding of the complex relationship between smoking and poorer outcomes in spine surgery as well as developing more efficacious cessation strategies.

Concepts: Effect, Effectiveness, Lumbar vertebrae, Vertebral column, Nicotine, Smoking cessation, Cervical vertebrae, Thoracic vertebrae

36

The scapula functions as a bridge between the shoulder complex and the cervical spine and plays a very important role in providing both mobility and stability of the neck/shoulder region. The association between abnormal scapular positions and motions and glenohumeral joint pathology has been well established in the literature, whereas studies investigating the relationship between neck pain and scapular dysfunction have only recently begun to emerge. Although several authors have emphasised the relevance of restoring normal scapular kinematics through exercise and manual therapy techniques, overall scapular rehabilitation guidelines decent for both patients with shoulder pain as well as patients with neck problems are lacking. The purpose of this paper is to provide a science-based clinical reasoning algorithm with practical guidelines for the rehabilitation of scapular dyskinesis in patients with chronic complaints in the upper quadrant.

Concepts: Vertebral column, Shoulder, Cervical vertebrae, Glenohumeral joint, Scapula, Acromion