My leg/knee has been bothering me lately during and a little bit after bowling.  I don't think it's serious but I don't want it to escalate to being serious.

It's only happened a few times in the last month, which is after I made a change to my game.  I went from walking towards my target(feet and entire body square to target in stance) to just opening my shoulders to my target(feet parallel with the boards in stance and walking straight).  When I'm swinging the ball a certain amount, or maybe it's most of the time regardless of line, I seem to turn my toes to the right after/during the slide and I'm right handed.

I have to assume that's what's causing the discomfort.  It doesn't hurt during the slide or anything.  At the same time though, if I'm opening my shoulders a certain amount, I feel like I have no choice but to have my foot turn that way probably due to the torque caused by throwing the ball.

I will say it looks like some pros don't face there body to their target until later in the approach.  Either way, there was a couple things I was thinking of trying and just hoping one of them work.  First was to just look at my target without actually trying to open up, hoping that I could still be accurate.  Second was to square myself to my target like before, but try not to walk in that direction.

Any advice?

Mine starts bothering me around 2-3 games.  I don't have to stop after that, it's more like a sore feeling.

It's hard for me to say exactly where it is hurting, but it's definitely in front and seems to be toward the right side(your left if you were facing me) but not actually on the side.