If your body is out of alignment from whatever reason- be it falls, MVA, sport injury, even being born can cause it.

It can also be more noticeable after having TOS for awhile due to possible guarding or posture changes due to pain.
Sometimes the change is very slight and as we age we get stiffer and our body is less fluid so things are more noticeable.

After reading some chiro sites about the atlas/axis {C1/C2} I realized that I have been out of alignment for 30+ yrs or maybe from birth- but who knows for sure.
I am pretty sure my shoulders were level and even until after my shoulder/neck "strains"- which I think was a precursor to TOS.
I had already had bilateral RSI a year before the shoulder strains started.
And I got RSI again as soon as they returned me to full work after PT for the shoulders.
I tend to get more of a sacroiliac pain inside low back/hip area.

A few here do get sciatic pain also.

So your pain is in the actual hip joint area?
Front, back, side of hip or deep inside?
Either way if it is very bothersome I'd have it looked at- just to be sure it's not something else.

DiMarie has some diagrams/photos/sketches posted in the useful links-
Heres the whole thread - in the first post is some good chiro links too- that can explain it in more detail.
http://neurotalk.psychcentral.com/showthread.php?t=84