• Sacrum
  • Ilium (part of the pelvic body on atlas)
  • Anterior sacroiliac ligament
  • Posterior sacroiliac ligament
  • Sacrospinous ligament
  • Sacrotuberous ligament

Posterior Sacroiliac ligament- Several flat ligamentous bands
- Arise from intermediate and lateral sacral crests
- Posterior superior iliac spine
- Internal lip of iliac crest
- Stabilise the sacroiliac joint
Anterior sacroiliac ligament- Broad ligamentous sheet
- Arises from sacral bodies 1-3
- Lateral and anterior margin of auricular surface of ilium- Stabilise the sacroiliac joint
Sacrospinous ligament- Ischial spine- Lateral sacrum and coccyx- Limits superior tilting stressors on the sacrum
Sacrotuberous ligament- Posterior superior iliac spine
- Transverse sacral tubercles
- Inferolateral sacrum
- Superolateral coccyx
- Medial portion of ischial tuberosity- Stabilise the pelvic girdle
- Limits superior tilting stressors on the sacrum