Sacrotuberous Ligament

Description

Arising from the lateral sacral margin and coccyx, the sacrotuberous ligament sweeps inferolaterally as a broad, fan-like sheet toward the ischial tuberosity, lying posterior to the pelvic floor musculature and deep to the region of gluteus maximus. Its expanded sacral attachment blends with the posterior sacroiliac ligamentous complex, while its distal fibers converge on the ischium, forming a fibrous boundary at the posteroinferior pelvis. Just anterior and slightly superior, the sacrospinous ligament runs to the ischial spine, together converting the greater and lesser sciatic notches into the greater and lesser sciatic foramina. Bony context includes the ilium, ischium, and pubis with the acetabulum laterally. This oblique lateral pelvic view clarifies how the sacrotuberous and sacrospinous ligaments stabilize nutation of the sacrum and define surgical corridors through the sciatic foramina. It also frames a common entrapment zone: the pudendal nerve exits the pelvis via the greater sciatic foramen, crosses near the ischial spine and sacrospinous ligament, then re-enters through the lesser sciatic foramen, a relationship tested in pudendal neuralgia and relevant during pudendal nerve blocks. A tight or thickened sacrotuberous ligament can also contribute to altered pelvic mechanics and pain around the posterior sacroiliac region. Small relationships matter here. Use this artwork for pelvic anatomy teaching in medical and physiotherapy curricula, for operative anatomy figures in texts on pelvic trauma fixation and posterior hip approaches, and for pain medicine materials describing pudendal nerve block landmarks and perineal neuropathies. Anatomical accuracy verified by SciePro's Medical Advisory Board.