The Sartorius muscle is not generally the main culprit in any pathology and dysfunction of the leg. Usually it gets "stuck" fascially to the Quadraceps. It sticks in your head because it is the longest muscle in the human body and when you pull your leg into the lotus position or to sit tailor style, you are engage it in it's fullest contraction.
Imagine my delight when this was the word of the day recently:
sartorial \sar-TOR-ee-uhl\, adjective:
1. Of or relating to a tailor or to tailoring.
2. Of or relating to clothing, or style or manner of dress.
3. [Anatomy] Of or relating to the sartorius muscle.
Most muscles are named for their shape or location or what they do. Sartorius is much more poetic than, say, the Levator Scapulae, which roughly translates to elevate the shoulder blade.