What happened to Goku's "Dragon Balls"? In the Dragon Ball Z: Super Android 13! movie, when Goku is fighting with Super Android 13, there is a scene that showed Super Android 13 punching Goku in the dragon.. uhmm... genitals.

Caution: This picture can cause unexpected pain in the crotch!
Watch it at your own risk.  

Is there any evidence that Goku managed to produce Goten before that fight?
Because I have a doubt about whether he could use them ever again.
Are the two circles in the picture (that appear to be torn apart) something else?
Considering the vast possibility of Goku eating a sensu bean after that, we can assume he regrew anything that was damaged. We also know that Goku is an alien. Although he looks human, he might not have balls there. Or balls at all. But if he does, like young Goku sometimes shown, he doesn't really use them that much :D