Are chromosomal abnormalities such as extra ones confined only to certain parts of the body?

No: Every cell in the body has the same complement of chromosomes.

All the same,but: The major abnormalities associated with chromosomal defects do seem to affect some specific body structures more than others.These are often the ones that require a lot of information to form right. The face/hands/heart are example areas where noticeable alterations are seen. Nonetheless, all cell lines in the body will have the same defect.