Psoas Major Muscle

Monday, October 10, 2011

The psoas major is a long muscle which arises from the transverse processes of the lumbar vertebrae and the fibrocartilages and sides of the vertebral bodies of the lower thoracic vertebrae and the lumbar vertebrae. The psoas major joins the iliacus to form the iliopsoas deep in the pelvis as it passes under the inguinal ligament and inserts in the femur lesser trochanter. It flexes and rotates the thigh and the spine. The psoas major is innervated by the anterior branches of the lumbar plexus nerve, and is supplied by the lumbar branch of the iliolumbar artery.