The STL has a broad fan-like origin from the sacrum, coccyx, ilium and sacroiliac joint capsule. Its fibers converge to course caudally to insert into the medial ischial tuberosity and additional fibers (known as the falciform ligament) extend to the ischial ramus .
- provides extensive insertion for the gluteus maximus muscle
- distal fibers partially blend with the proximal tendon of the long head of biceps femoris
- sacrospinous ligament
- dorsal sacroiliac ligament
- pudendal nerve entrapment syndrome
- may be secondary to sacrotuberous ligament calcification (see Case 1)