Alot of times when you are making a madman, your wrist will break upon hitting uke. to fix this, view the replays and use the "e" button to go about 5-10 frames before the impact. now you can try a few things such as contracting your wrist(usually works best) relaxing wrist, or ungripping your wrist.
your wrist may break After the initial imapact. if this happens, again use the "e" button to either relax your wrists and/or arms, or if that still fails, let go of uke with one or both hands and go for another hit
Another tip: if you grab uke with both hands on the same joint or a joint very far away. (such as arm and abs) dont try to rip uke apart. it will only result in an embarrasing and frustrating snapping of the wrist. I only attempt to rip if my grips are 1 joint away. if uke still doesnt dismember, try going back with the "e" button again, and relaxing your wrist before impact (about 10 frames) (also works with kicks(ankle)