Anyone know of an image that shows hip anatomy when in side splits?

I have been working on my splits. I basically realized without them, I might as well not even try to achieve a lot of movements I want to. I think splits (side and front) are necessary. With them everything will get easier, from flags to hand stands to even a basic cartwheel. 

Looking at hip anatomy images, it looks like the splits shouldn't even be possible. I would like to know at what position the femoral head and neck are when in the splits, in relation to the pelvis, and pelvic tilt. So far I have not found anything. I have found descriptions of pelvic tilt, but no anatomical images.

Also I wonder if the difference between feet forward and feet up in the splits is basically an issue of pelvic tilt, and if the femoral neck changes much in the acetabulum when switching from feet up to feet forward or 'rocking' in the side splits.

Thanks

Starting on pg 94-95 for front split , pg 46-47 for a lead in to side split.

http://www.bandhayoga.com/MC2_inside.html

nice cole, thank you for this page

Cole Dano said:

Starting on pg 94-95 for front split , pg 46-47 for a lead in to side split.

 

http://www.bandhayoga.com/MC2_inside.html

Thanks, but I was looking more for bone rather than muscular positions. I think I have found something that simply does not exist, on the internet. 

I found a video on youtube that gets pretty close, showing the femoral head while in straddle. Looks like some sort of PT software: