Search results for "Posterior arch"
showing 4 items of 4 documents
Shape change in the atlas with congenital midline non-union of its posterior arch: a morphometric geometric study.
2017
Background Context The congenital midline non-union of the posterior arch of the atlas is a developmental variant present at a frequency ranging from 0.7% to 3.9%. Most of the reported cases correspond to incidental findings during routine medical examination. In cases of posterior non-union, hypertrophy of the anterior arch and cortical bone thickening of the posterior arches have been observed and interpreted as adaptive responses of the atlas to increased mechanical stress. Purpose We sought to determine if the congenital non-union of the posterior arch results in a change in the shape of the atlas. Study Design/Setting This study is an analysis of the first cervical vertebrae from osteo…
The Retrotransverse Foramen of the Atlas Is not a Modern Anatomic Variation
2019
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…
Difficulties in distinguishing between an atlas fracture and a congenital posterior atlas arch defect in postmortem analysis.
2013
We found one atlas from a sample of 148 skeletons (0.67%) that presented different anatomical variations which made it difficult to determine whether the vertebra had an atlas fracture, an unusual Type B posterior atlas arch defect, or a combination of both. We carried out a stereomicroscopy, radiographic, and computerized tomography scan study that revealed that the dry atlas we found presented a very uncommon congenital Type B posterior atlas arch defect, simulating a fracture. In short, the present paper has revealed that differentiating Type B posterior atlas arch defects from fractures in post-mortem dry vertebrae is more difficult than expected. Thus we believe that it can be easier t…
Posterior Approach to Axis Instability
2016
Many pathologies can cause instability of the cranio-vertebral junction (CVJ). Among the most common diseases must be considered thraumatisms, neoplasms, inflammation, but also congenital malformations. Instability of the CVJ is a potentially life-threatening condition and improper treatment can lead to severe neurological deficits as well as continuous, excruciating pain in the neck. Conservative treatments are often disappointing and surgery must always be taken in consideration when approaching instability of the CVJ, being in many cases the only therapy that can provide satisfactory results.