Malformations of central pillar Malformations of surrounding rings Disturbance of axial component of occipital sclerotome, proatlas and C1 resegmented sclerotome Disturbance of lateral component and hypochordal bows of proatlas and…

Fig. 1 Images of a 2.5 year old boy. (a) Sagittal view of CT scan showing craniovertebral instability. (b) Axial view of arch of atlas showing its trifid nature. (c)…

Fig. 1 Modified scheme [131] of the vasculature in the human embryo (right half) at week 4 Primitive aortic arches develop in regular order from cephalic to caudal. There are…

Fig. 1 Normal adult CT (a) and 22-month-old MRI (b) sagittal landmarks. A nasion, B tuberculum sellae, C dorsum sellae, D basion, E opisthion, F posterior margin of the hard…

Fig. 1 (a) Illustration showing the ossification centers and synchondroses of the atlas. The neural arch ossification centers form during the seventh gestational week, whereas the ossification center within the…

Fig. 1 (a, b) Flexion/extension MRI study in a MPS IVA case, showing increased cord compression during flexion Main features to consider in MPS are: the presence of odontoid hypoplasia,…

Class Description I The patient is normal and healthy II The patient has mild systemic disease that does not limit their activities (e.g., controlled hypertension or controlled diabetes without systemic…

Embryologically, the occipital bone results from the fusion of four occipital sclerotomes, of which the proatlas is the most caudal. The atlas derives from the proatlas and C1 sclerotome. The…

(1) Pediatric Neurosurgical Departement, Hôpital Necker-Enfants Malades, APHP, 149, Rue de Sèvres, Paris, 75743, France (2) Genetic Department, National Reference Centre for Congenital Bone Diseases, Hôpital Necker-Enfants Malades, INSERM U781,…