Sacrotuberous Ligament

Description

Arising from the lateral margin of the sacrum and coccyx, the sacrotuberous ligament courses inferolaterally to insert on the ischial tuberosity, forming a broad fibrous band along the posterior pelvis. Medial to it sit the sacral foramina and the pelvic surface of the sacrum, while laterally the ligament lies adjacent to the ischial spine region and the posterior aspect of the acetabular area. From an internal pelvic viewpoint, its fibers contour the pelvic outlet and define the posterior boundary of the lesser pelvis in relation to the pelvic floor musculature. Orientation is clear. Clinically, this ligament matters because it converts the greater and lesser sciatic notches into the greater and lesser sciatic foramina when paired with the sacrospinous ligament, creating the passageways used by the sciatic nerve, pudendal nerve, and internal pudendal vessels as they exit and re-enter the pelvis. Its insertion on the ischial tuberosity also places it in the same mechanical neighborhood as the hamstring origin, so posterior pelvic pain can blur between sacrotuberous strain, proximal hamstring tendinopathy, and sacroiliac joint dysfunction. Pelvic surgeons use it as a landmark when working near the ischioanal fossa and during approaches that require awareness of pudendal neurovascular pathways and pudendal nerve entrapment patterns. Use this illustration for teaching pelvic outlet anatomy in gross anatomy, pelvic floor modules, and sports medicine content addressing posterior pelvic pain generators and differential diagnosis at the ischial tuberosity. It also suits surgical atlases discussing transgluteal or perineal corridors and any publication clarifying the boundaries of the sciatic foramina and adjacent ligamentous supports in the male pelvis. Anatomical accuracy verified by SciePro's Medical Advisory Board.