Position of iliacus muscle (shown in red.)
The iliacus and nearby muscles
|Origin||upper two-third of the iliac fossa|
|Insertion||base of the lesser trochanter of femur|
|Artery||medial femoral circumflex artery, iliac branch of iliolumbar artery|
|Actions||flexes and rotates laterally thigh|
|Anatomical terms of muscle|
The iliacus arises from the iliac fossa on the interior side of the hip bone, and also from the region of the anterior inferior iliac spine (AIIS). It joins the psoas major to form the Iliopsoas as which it proceeds across the iliopubic eminence through the muscular lacuna to its insertion on the lesser trochanter of the femur. Its fibers are often inserted in front of those of the psoas major and extends distally over the lesser trochanter. 
In open-chain movements, as part of the iliopsoas, the iliacus is important for lifting (flexing) the femur forward. In closed-chain movements, the iliopsoas bends the trunk forward and can lift the trunk from a lying posture (i.e. sit-ups) because the psoas major crosses several vertebral joints and the sacroiliac joint. From its origin in the lesser pelvis the iliacus acts exclusively on the hip joint.
Right hip bone. Internal surface. (Iliac fossa visible at upper left.)
- Platzer (2004), p 234
- Thieme Atlas of Anatomy (2006), p 422
- Platzer, Werner (2004). Color Atlas of Human Anatomy, Vol. 1: Locomotor System (5th ed.). Thieme. ISBN 3-13-533305-1.
- Thieme Atlas of Anatomy: General Anatomy and Musculoskeletal System. Thieme. 2006. ISBN 1-58890-419-9.
|Wikimedia Commons has media related to Iliacus muscles.|
- Origin, insertion and nerve supply of the muscle at Loyola University Chicago Stritch School of Medicine
- -181075889 at GPnotebook
- Anatomy figure: 40:07-05 at Human Anatomy Online, SUNY Downstate Medical Center - "Muscles and nerves of the posterior abdominal wall."
- pelvis at The Anatomy Lesson by Wesley Norman (Georgetown University) (femalepelvicdiaphragm, malepelvicdiaphragm)