The iliacus and psoas major muscles of the hip are so closely related in structure and function that they are often referred to as a single muscle, the iliopsoas. While each muscle has its own origin — the iliacus arises from the ilium and the psoas major arises from the lumbar vertebrae — both muscles merge at their midpoint to form a common insertion at the lesser trochanter of the femur.
Working together, the muscles of the iliopsoas are the most powerful flexors of the thigh at the hip joint. Continue Scrolling To Read More Below...