Kuroda Michiyou
Nah, its also a snail/slug thing too. Tsunade's Katsuyu regenerates too.
Since we're being geeky, it is a kinda blatant refrence to nameks being slug-like in that they posess no bones, and regenerate lost limbs. having seen the Trunks special in the USA done by Funi, I noticed Gohan had only one arm near the end when he died. his swan song was basically a one armed fight, like being a one-legged man in an a**-kicking contest.
and yeah I noticed Piccolo's severed arm and regenerate trick. handy when you lose a limb, Cell used it quite frequently, and because he was a bio-android he too lacked bones, based on his design.
Tsunade and her summon Katsuyu are in relation to Tsunade's medical prowess. Tsunade can harm and heal with her medical knowledge, and spearheaded/inspired the incorporation of medical-nin in a group effort to improve the group's survivability.
I love it when Psycho gets irked by my spurring of anime geekiness. XD