I understand that one of the evidences for rape is abrasions in the vaginal area, because the woman is typically not "ready" in those assaults. Does that mean that the rapist has sustained an abrasion injury, too? If so, has that ever helped to make a case?

It seems possible and even likely that the rapist would. But I've never heard of a case where a rapist was convicted solely based on an abrasion injury. Now if there's dna evidence, hairs and fibers, or other injuries (like maybe the victim scratched her attacker, the rapist has scratch marks, the victim has his skin cells uner her nails) plus there's abrasion injuries, it ony makes sense that a jury would find the rapist guilty.

Wow