I split this into its own thread for easier discussion.
Most people think of compartment syndrome as the acute kind like football players might get if they receive a blow to the leg (that kind requires immediate surgery).
I have known several vaulters with chronic compartment syndrome. It's like a horrible case of shin splints that just won't go away no matter how much you rest. One of the key indicators is that it is accompanied by a feeling of tightness and pressure in the calves.
To test for it (once they have ruled out stress fractures and other, more common, things), I think they have you run on a treadmill to aggravate it, then they jab you with a needle and do a pressure test.
If rest, massage, and other standard shin splint symptoms do not relieve the problem, then the main treatment is a fasciotomy.
I know some people that got the surgery and it helped, others chose to modify their training (lots of stairs and almost no running except for vaulting) and were able to try and make it work.
Here is some info:
http://foothealth.about.com/od/exercise ... ndro_2.htm