Lower limb

Iliacus

Musculus iliacus

Origin

Iliac fossa of the ilium

Insertion

Lesser trochanter of the femur (together with psoas major as iliopsoas)

Function

Flexion of the hip

Innervation

Femoral nerve, L2-L4

Movement & chain

Together with psoas major forms iliopsoas, the most important hip flexor, crucial for lifting the leg during walking and climbing stairs.

Palpation

Palpable in the iliac fossa medial to the ASIS by gently pressing posterior-medially into the lower quadrant with the hip slightly flexed.

Clinical

Iliopsoas hematoma (e.g. in anticoagulated patients) causes acute femoral nerve compression and quad weakness; iliopsoas bursitis and abscess.

Segmental innervation

L2-L4, used when testing the upper lumbar myotomes.

In clinical practice

Frequent repositioning to prevent trochanteric and heel pressure ulcers; ensure hip dislocation precautions in total hip arthroplasty patients.

Region in the model

Lower limb