I remembered the reports saying that a baton was hanging out of his clothing, but I checked back, and you are correct. Those are images I can't unsee.

A lot of it is psychological warfare in the sense that they emasculate the men and make them more "woman" like, thus weaker, by raping them. If you do some Googling, you will find this is very common in this culture. An example: Gaddafi was raped with a baton when he was captured by his captors.