Iliopsoas muscles

long fusiform muscle located in the lumbar region

The iliopsoas muscle (; ) refers to the joined psoas major and the iliacus muscles. The two muscles are separate in the abdomen, but usually merge in the thigh. They are usually given the common name iliopsoas. The iliopsoas muscle joins to the femur at the lesser trochanter. It acts as the strongest flexor of the hip.

flat, triangular muscle which fills the iliac fossa