The Retrotransverse Foramen of the Atlas Is not a Modern Anatomic Variation

Background The retrotransverse foramen (RTF) is a nonmetric variant of the atlas vertebra that consists of an abnormal accessory foramen located on the posterior root of the transverse process and it extends from the posterior root of the transverse process to the root of the posterior arch. Its presence has been related to regional variations of the venous circulation. It is currently unknown whether the RTF is a modern or an ancient anatomic variation. Case Description We analyzed the skeletal remains from the late-ancient Roman necropolis (II-VI centuries ad ) of La Boatella (Valencia, Spain) and we found a well-preserved individual skeleton that presented with a left retrotransverse for…

Cortical bone thickening in Type A posterior atlas arch defects: experimental report.

Abstract Background Context To date, no information about the cortical bone microstructural properties in atlas vertebrae with posterior arch defects has been reported. Purpose To test if there is an increased cortical bone thickening in atlases with Type A posterior atlas arch defects in an experimental model. Study Design Micro-computed tomography (CT) study on cadaveric atlas vertebrae. Methods We analyzed the cortical bone thickness, the cortical volume, and the medullary volume (SkyScan 1172 Bruker micro-CT NV, Kontich, Belgium) in cadaveric dry vertebrae with a Type A atlas arch defect and normal control vertebrae. Results The micro-CT study revealed significant differences in cortica…

Association between ribs shape and pulmonary function in patients with Osteogenesis Imperfecta

Graphical abstract

Prevalence of anatomic variations of the atlas vertebra

Abstract BACKGROUND CONTEXT The retrotransverse foramen (RTF), arcuate foramen (AF), unclosed transverse foramen (UTF) and posterior atlas arch defects (PAAD) are anatomic variations of the atlas vertebra that surgeons must be aware of before spine surgery is performed. PURPOSE To analyze the prevalence of the AF, RTF, UTF, and PAAD. STUDY DESIGN Ex-vivo anatomical study. PATIENT SAMPLE Two hundred eighteen atlas vertebrae obtained from 100 Caucasian subjects and 118 sub-Saharan African subjects (48 Sotho subjects, 35 Xhosa subjects and 35 Zulu subjects). METHODS We studied 218 atlas vertebrae from skeletons of the Raymond A. Dart Collection in order to analyze the prevalence of AF, RTF, UT…

Atlases with Arcuate Foramen Present Cortical Bone Thickening That May Contribute to Lower Fracture Risk.

To date, no information about the cortical bone microstructural properties in atlas vertebrae with arcuate foramen has been reported. As a result, we aimed to test in an experimental model if there is a cortical bone thickening in an atlas vertebra which has an arcuate foramen that may play a protective role against bone fracture.We analyzed by means of micro-computed tomography the cortical bone thickness, the cortical volume, and the medullary volume (SkyScan 1172 Bruker micro-CT NV, Kontich, Belgium) in cadaveric dry atlas vertebrae with arcuate foramen and without arcuate foramen. We also reviewed a case series of 31 posterior atlas arch fractures to correlate the possible presence in t…

Short review: Field recovery and potential information value of small elements of the skeleton

The recovery of small elements of the skeleton (e.g. hyoid, carpals, and hand and foot phalanges) is one of the established tasks of the archaeologist and physical anthropologist when working in the field, whether in an archaeological or forensic context. In the present work, we illustrate the field location of ossified laryngeal cartilages, hand sesamoids, and the medial clavicular epiphyses. The potential information offered by these elements is briefly summarized. The frequency of these elements observed in a cemetery dating from 1943 indicates the possibility that these elements could be found in other contexts at a higher frequency than expected.

Krapina atlases suggest a high prevalence of anatomical variations in the first cervical vertebra of Neanderthals

The first cervical vertebra, atlas, and its anatomical variants have been widely studied in Homo sapiens. However, in Neanderthals, the presence of anatomical variants of the atlas has been very little studied until very recently. Only the Neanderthal group from the El Sidrón site (Spain) has been analysed with regard to the anatomical variants of the atlas. A high prevalence of anatomical variants has been described in this sample, which points to low genetic diversity in this Neanderthal group. Even so, the high prevalence of anatomical variations detected in El Sidrón Neanderthal atlases needs to be confirmed by analysing more Neanderthal remains. In this context, we analysed the possibl…

Double Retrotransverse Foramen of Atlas (C1)

Background The retrotransverse foramen is a nonmetric variant of C1 that consists of an abnormal accessory foramen on the posterior root of the transverse process. Case Description During a study on the prevalence of the retrotransverse foramen in 150 dry C1 vertebrae, we observed an exceptional C1 (0.67%) with a right double retrotransverse foramen of the 14 C1 vertebrae (9.3%). This has not been reported previously in the literature. No osteogenic reaction and no degenerative signs were observed in this C1 with the double retrotransverse foramen. Conclusions Neurosurgeons should be aware of the possible presence of the “conventional” retrotransverse foramen and the “exceptional” double re…

Can the transverse foramen/vertebral artery ratio of double transverse foramen subjects be a risk for vertebrobasilar transient ischemic attacks?

The C6 is the cervical vertebra into which the vertebral artery enters the passage of the transverse foramen and it is the vertebra most affected by double transverse foramina. There is currently little information about the relation between the vertebral artery and the double transverse foramen in C6. We aimed to test whether subjects with a double transverse foramen in C6 have a reduced transverse foramen/vertebral artery ratio when compared with normal anatomy subjects who possess a single transverse foramen which may be a risk for transient vertebral artery stenosis. We measured the area of the transverse foramen and the vertebral artery in 27 double transverse and 56 normal anatomy sub…

Congenital cervical vertebrae clefts in Klippel-Feil syndrome

Analysis of the relationship between the double transverse foramen and the possibility of developing clinical symptoms after whiplash

Introduction: Currently there is no information about the possibility of developing clinical symptoms after whiplash in double transverse foramen subjects. Our aim was to test whether subjects with double transverse foramen have an increased risk of presenting with acute headache, dizziness, vertebral artery dissection, and vomiting after whiplash. Methods: We recorded the absence/presence of double transverse foramen, and the absence/presence of neck pain, acute headache, dizziness, vertebral artery dissection, and vomiting in 85 patients who had suffered whiplash injuries in car rear-end impacts in road traffic accidents. We used the odds ratio test to determine whether double transverse …

The Decreasing Prevalence of the Arcuate Foramen

[Background]: The arcuate foramen (AF), or ponticulus posticus, is an anatomic variant of the first cervical vertebra that consists of a complete or partial osseous bridge over the groove for the vertebral artery and extends from the posterior aspect of the superior articular facet to the superior lateral border of the posterior arch. The AF has been associated with clinical symptoms, such as headache, migraine, neck pain, shoulder pain, arm pain, and vertebral artery dissection. We aimed to test whether the prevalence of the AF has decreased in the modern human population over the past centuries as a result of reduction in inbreeding and endogamy.

Unexpected Persistent Dentocentral Synchondrosis of C2.

Background The persistence of synchondrosis in adulthood can confound diagnostic decisions made during patient management. Case Description A 59-year-old woman who presented neck pain, acute headache, and acute cervical myelopathy symptoms after suffering whiplash grade 3 in a car rear-end impact underwent a conventional radiologic study that revealed no fracture and no anatomic spine variations. The magnetic resonance imaging study revealed no spinal cord intensity signal changes, but it showed a persistent (remnant) dentocentral synchondrosis that was undetected in a previous conventional radiographic evaluation. Conclusions The localization and level of the remnant of the dentocentral sy…