really tight inner thighs

[Nokomis]

http://muscleventures.com/video/2007...h_stretch.html
and a few more here... http://www.hksi.org.hk/function/triathlon/stretch4.htm

Go easy & start with warm muscles. Commuting in a Seattle downpour? straight into the tub!

[Pika]

Hi mimmi:
Looks like Knott gave you some good stretches for your inner thigh- it is a good idea to keep doing them gently- stretching aggresivley won't help very much. Sometimes more isn't better- be sure to stretch so you feel the muscle "release" ie when you hold the stretch after about 30s it should feel easier not worse or tighter.
Sometimes when you have a cranky back/SI the nerves from there become facilitated- meaning they are hypersensitive- when this happens they can start sending more than the usual number of signals to the muscle and one of the first symptoms people get is chronic muscle tightness that doesn't improve with rest/stretching.
The adductors ( inner thigh muscles) are a huge stabilizer of the pelvis so it might be that those muscles are kicking in to help with your pelvis and that is why they are not letting go.
Are you doing other core stabilizing exercises? Any transverse Abdominal exercises? That would be a good start if you aren't.
Do PTs do IMS there (Intramuscular Stimulation) it is a needling technique that can be a huge help with chronic muscle tightness ( chronic being over 6weeks with no underlying pathology ie inflammation injusry etc)
hope that helps