Final answer:
The muscle with a tendon passing through the lesser sciatic foramen is innervated by the pudendal nerve, identified in pelvic anatomy.
Step-by-step explanation:
The muscle that has a tendon passing through the lesser sciatic foramen is innervated by the pudendal nerve. This foramen is a pelvic opening formed by the lesser sciatic notch of the hip bone, the sacrospinous ligament, and the sacrotuberous ligament. The pudendal nerve is responsible for innervating the muscles, including those associated with the perineum, that course through the lesser sciatic foramen.