Anatomy of bone system. The manual for medical students / Анатомия костной системы. Учебное пособие для медицинских вузов. Г. И. Ничипорук

assimilation – partial or complete fusion of the I and II vertebrae.

      2. Manifestation of the atlas (formation of the occipital vertebra – proatlas) –inclusion of the atlas particles into the occipital bone which is manifested in the presence of anomalous bony prominences in the circle of the great (occipital) foramen.

      3. Kimmerle`s anomaly – transformation of the vertebral artery groove on the atlas into the canal as a result of formation of a bony outgrowth above this groove.

      4. Development anomalies of the II cervical vertebra:

      – agenesia (absence) of the dens;

      – the dens and the body of the II cervical vertebra are not fused together.

      5. Thoracolisation of the cervical vertebrae – formation of cervical ribs (most often from the VII cervical vertebra).

      6. Sacralisation – fusion of the V lumbar vertebra with the I sacral vertebra: there are 4 vertebrae in the lumbar part of the vertebral column; the sacrum consists of 6 vertebrae.

      7. Lumbarisation – the I sacral vertebra and the II sacral vertebra are not fused together: there are 6 vertebrae in the lumbar part of the vertebral column; the sacrum consists of 4 vertebrae.

      8. Segmented sacrum – in this case, the sacral vertebrae are not fused into a single bone. This is not anomaly in children, because the presence of cartilaginous tissue between vertebral bodies is normal for this age.

      9. Splitting of the sacral canal, spina bifida sacralis: partial or complete.

      10. Anomalies of the coccygeal vertebrae:

      – different number of coccygeal vertebrae (1 to 5);

      – different variations of fusion of the coccygeal vertebrae together or with the sacrum.