The iliopsoas is a muscle in the anterior compartment of the thigh. It is comprised of two separate muscles; the psoas major and iliacus. These muscles arise in the pelvis and pass under the inguinal ligament into the anterior compartment of the thigh – where they form a common tendon. Attachments: Psoas major – originates from the lumbar vertebrae Iliacus – originates from the iliac fossa of the pelvis. They insert together onto the lesser trochanter of the femur. Actions: Flexion of the the thigh at the hip joint. Innervation: Psoas major – anterior rami of L1-3 Iliacus – femoral nerve. Blood supply: Iliolumbar branch of the internal iliac artery, with contributions from the obturator and femoral arteries. By TeachMeSeries Ltd (2025) Fig 1The muscles of the anterior thigh. Pro Feature - 3D Model You've Discovered a Pro Feature Access our 3D Model Library Explore, cut, dissect, annotate and manipulate our 3D models to visualise anatomy in a dynamic, interactive way. Learn More Print Article Rate This Article