Final answer:
The provided material does not detail the grades of sacrococcygeal teratomas but instead covers the grades of spina bifida: occulta, meningocele, and myelomeningocele. These grades range from mildest with no symptoms to the most severe with neurological symptoms. For sacrococcygeal teratomas, a specific grading system would be required.
Step-by-step explanation:
The grades of sacrococcygeal teratomas, which are tumors that can occur at the base of the spine, are not detailed in the provided reference material. Instead, the reference material discusses conditions related to the spinal cord such as spina bifida. Spina bifida has three grades: occulta, meningocele, and myelomeningocele. Spina bifida occulta is the least severe form and may not cause functional differences as the spinal cord itself is not affected. Meningocele involves meninges protruding through the spinal column without necessarily involving nerves. Finally, myelomeningocele is the most severe form where both the meninges protrude and spinal nerves are involved, leading to possible severe neurological symptoms.
In terms of sacrococcygeal teratomas, these are complex tumors that require a different grading system, which is not covered within the scope of the given text. For accurate grading, information specific to sacrococcygeal teratomas rather than spinal conditions would be necessary.