Dry needling for my piriformiss muscle

What the HECK???? So I am still on mending terms when it comes to running which has been quite difficult. I thought after taking 6 weeks completely off I would be miraculously healed and have the ok to start again. The joke was on me. I have been training with different weights, circuits, stretches, weird brief 100 yard running techniques but the pain seems to hang around. My PT went to a class over the weekend and came back Tuesday and told me that she had a list of people she wanted to try this out on and I was one of the lucky winners. WOO HOO Needless to say it involves needles and some major pain. The first few in the lower back weren't too bad it was when she got into my piriformiss muscle that I was feeling it (Basically your butt muscle).How does trigger point dry needling work?
"Trigger Point Dry Needling is thought to work by disrupting a reflex arc of contracted tissue to allow improved blood flow and healing to the area, as well as stimulating biochemical changes. Dry needling utilizes a very thin filament needle. The needle is inserted into the trigger point and a local twitch response is ideally elicited. This twitch response is an involuntary contraction of the muscle that allows the muscle to relax. The needle used is similar to an acupuncture needle, but is not considered acupuncture and is based on Western physiologic approaches. Electrical stimulation with heat can also be applied to the needle to elicit these twitches to help the muscle relax." When options start being limited this is the route we are attempting to take. I have to say before she tested some of my flexibility and then after and the difference was quite amazing. I am still sore and I am still suffering pain in my leg and knee but I just don't know what else to do besides listening to my PT. I am hoping with some more neurological work that we can get to the bottom of this along with strengthening. I am able to do 3 miles. One has to be a walk run, one moderate run and one 80%. I find my 80% getting a little too fast and I think that is because it is the thrill of the run. I pray that this will heal because I am ready to start training next month for a few more marathons. PLEASE HEAL