Incomplete Formation of Vertebrae
During fetal development, the spine and vertebral column develops first as a single column of tissue and later becomes segmented to form the bony vertebrae. Sometimes a vertebrae will not completely form, forming what is known as a hemivertebrae. This vertebrae will cause a sharp angle in the spine and a curvature that can worsen as a child grows. The abnormality can occur at one vertebrae in the spine or many vertebrae.
Failure of Separation of Vertebrae
If during this time ofvertebral development the tissue does not fully separate, it may result in a partial fusion (bars) between vertebraes. As a result, as the child grows, the connection will prevent the spine from growing evenly and properly resulting in a curve. Both failures of separation and incomplete formation can occur together.