The iliacus is a fan-shaped muscle that lines the iliac fossa of the pelvis. It arises from the iliac fossa and joins the psoas major tendon to insert on the lesser trochanter of the femur. The femoral nerve supplies it, and it flexes the hip.
| Origin | Iliac fossa, ala of the sacrum and anterior sacroiliac ligaments. |
|---|---|
| Insertion | Lesser trochanter of the femur, by the tendon of psoas major. |
| Innervation | Femoral nerve (L2-L3). |
| Blood supply | Iliac branch of the iliolumbar artery and the deep circumflex iliac artery. |
| Action | Flexes the thigh at the hip and stabilises the hip joint and trunk. |
3D model: BodyParts3D (CC BY 4.0), adult male reference anatomy. Highlighted structure shown with nearby bones for context.
Together with psoas major it forms the iliopsoas. The femoral nerve lies in the groove between the two muscles.
The femoral nerve.
It flexes the hip, working with psoas major.
Test yourself
Abdomen and pelvis muscle quiz
Practise origins, insertions, nerve supply and locations with instant feedback.
Explore in context
Open the iliacus in the full 3D atlas
Toggle body systems, explode the model and inspect every neighbouring structure.