Final answer:
The clinical term for the condition in which the vertebral laminae fail to unite during development is spina bifida. It is a birth defect of the spinal cord caused when the neural tube does not completely close. There are three classes of this disorder: occulta, meningocele, and myelomeningocele.
Step-by-step explanation:
The clinical term for the condition in which the vertebral laminae fail to unite during development is spina bifida. Spina bifida is a birth defect of the spinal cord caused when the neural tube does not completely close. This results in the emergence of meninges and neural tissue through the vertebral column. There are three classes of this disorder: occulta, meningocele, and myelomeningocele. Occulta is the mildest form, where the vertebral bones do not fully surround the spinal cord. Meningocele is when the meninges protrude through the spinal column, and myelomeningocele involves the protrusion of meninges and spinal nerves, leading to severe neurological symptoms.