Vertebral defect
Different forms of defects occur during formation of vertebral column, some are of high clinical significant and can be corrected by surgery,
Spina Bifida: Is a condition that is caused by imperfect fusion or nonunion of the embryonic neural arch, resulting in exposure of the neuronal tissues covered by a thin membrane (fig. 22)
Different forms of defects occur during formation of vertebral column, some are of high clinical significant and can be corrected by surgery,
Spina Bifida: Is a condition that is caused by imperfect fusion or nonunion of the embryonic neural arch, resulting in exposure of the neuronal tissues covered by a thin membrane (fig. 22)
- Spina bifida occulta is a type of spina bifida which involve only the bony vertebral arch leaving the spinal cord intact. It is covered by a thick membrane or skin.
- Spina bifida cystica, is a severe type of spina bifida involving the spinal cord and meninges, in which the neural tube fails to close, vertebral arches fail to form and the neural tissue is exposed (fig. 23)
Chordoma: Is a condition of malignant tumor caused by the persistence of remnants of notochord, and infiltrates the bone, thereby difficult to remove.
Scoliosis (lateral curvature): Is a situation cause when two successive vertebrae fuse asymmetrically or have half a vertebrae missing. This is due to the complicated nature of formation of the vertebral column
Rachischisis (cleft vertebral column): Is a vertebral abnormality in a complex group of anomalies (axial dysraphic disorders) that primarily affect axial structures. In these infants, the neural folds fail to fuse and the neural and vertebral defects may be extensive or be restricted to a small area.
Variation in the Number of Vertebrae:The number of the vertebrae is frequently more or less than the normal. A typical example of this anomaly is found in patient with Klippel-Feil anomaly, which have fewer than normal cervical vertebrae. Though, an apparent extra (or absent) vertebra in one segment may be compensated for by an absent (or extra) vertebra in an adjacent segment; example, 4 lumbar with 6 sacral.
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(Copyright © 2011 by U. Bala)