Foramen ischiadicum majus

The greater sciatic foramen is a foramen within the pelvis and is a major conduit of neurovascular structures from the pelvis to the lower limb. The greater sciatic foramen is separated from the lesser sciatic foramen below by the sacrospinous ligament.

Gross anatomy

Boundaries

In a clockwise fashion, its boundaries include:

• superior: anterior sacroiliac ligament
• posteromedial: sacrotuberous ligament
• inferior: sacrospinous ligament and ischial spine
• anterolateral: greater sciatic notch

Contents

Many structures enter or exit the pelvis through the greater sciatic foramen and are broadly divided based on whether they lie above or below the piriformis muscle - the suprapiriform and infrapiriform foramen respectively.

Suprapiriform foramen

• superior gluteal vessels
• superior gluteal nerve

Infrapiriform foramen

• inferior gluteal vessels
• internal pudendal vessels
• nerves of the sacral plexus
  • inferior gluteal nerve
  • pudendal nerve
  • sciatic nerve
  • posterior femoral cutaneous nerve
  • nerve to obturator internus
  • nerve to quadratus femoris

Siehe auch:

• Nervus ischiadicus
• Becken
• Musculus piriformis
• Incisura ischiadica major
• Sulcus paraglenoidalis

und weiter:

• Arteria iliaca interna
• lower extremity neuropathy