Knee problems during stretches

[Silvance]

I've hit a wall in my major leg stretches. Whenever I do any toe touching stretches, it feels like my inner knee (the sides of my knees that are facing inward) is about to pop out, and it's gotten to the point where I no longer feel a real stretch in my hamstrings, because my knees are preventing me from stretching any further. I'm unsure of what I can do about this. Any help would be appreciated.

[Dao]

That sounds like your feeling the stretch in the medial hamstring tendons, specifically the semitendinosis. If the sensation radiates toward the calf then it is possibly the semimembranosis too.
The tendon of the semitend. wraps the medial condyle of the tibia and below it lays a bursae, which if inflammed can cause pain.

One suggestion would be to make sure your back is hollow whilst your stretching to give you an anterior pelvic tilt, thus pulling the hamstrings from the ischial tuberosity.

Dao

[Fish Of Doom]

wouldn't that stretch your lower back instead?

edit: nvm i'm an idiot. wrong pelvic tilt :p

[Silvance]

I'm afraid I don't understand what "keep your back hollow" means.

[Fish Of Doom]

push your abdomen out and your chest and hips back to accentuate the curve of your lower back.