The sciatic foramen is located in the posterior human pelvis.
The sciatic foramen is essentially an opening within the pelvis that allows structures to pass from the pelvis into the gluteal region (buttocks) and the lower limb. It is divided into the greater and lesser sciatic foramina by the sacrospinous ligament. The greater sciatic foramen is larger and more superior, while the lesser sciatic foramen is smaller and more inferior.
Greater Sciatic Foramen
- Location: Posterior pelvis
- Formation: Formed by the greater sciatic notch of the ilium and ischium, and the sacrotuberous and sacrospinous ligaments.
- Contents: Structures that pass through the greater sciatic foramen include:
- Piriformis muscle
- Sciatic nerve
- Superior and inferior gluteal arteries and nerves
- Posterior femoral cutaneous nerve
- Pudendal nerve and internal pudendal vessels
- Nerve to obturator internus
- Nerve to quadratus femoris
Lesser Sciatic Foramen
- Location: Inferior to the greater sciatic foramen in the posterior pelvis.
- Formation: Formed by the lesser sciatic notch of the ischium and the sacrotuberous and sacrospinous ligaments.
- Contents: Structures that pass through the lesser sciatic foramen include:
- Tendon of the obturator internus muscle
- Pudendal nerve and internal pudendal vessels
- Nerve to obturator internus
In summary, the sciatic foramen (both greater and lesser) are important anatomical openings in the posterior pelvis that allow nerves and vessels to connect the pelvis to the lower limb and perineum.
