Where does the psoas major insert?

Where does the psoas major insert?

• A. Onto the lesser trochanter of the femur as part of the iliopsoas with the iliacus.
• B. Onto the greater trochanter of the femur.
• C. Onto the head of the femur.
• D. Onto the medial condyle of the tibia.

Answer: (A)

The psoas major inserts on the lesser trochanter of the femur as part of the iliopsoas tendon with the iliacus. This placement is what lets the muscle powerfully flex the hip, bringing the thigh toward the trunk when you lift the leg or walk. The tendon mingles with iliacus to form the iliopsoas, which travels under the inguinal ligament and attaches at that lesser trochanter point. Why the other sites don’t fit: the greater trochanter is the attachment for the gluteal muscles and deep rotators, not the psoas major. The head of the femur is not a muscle insertion site. The medial condyle of the tibia is where muscles crossing the knee insert, not where the psoas major attaches.

The psoas major inserts on the lesser trochanter of the femur as part of the iliopsoas tendon with the iliacus. This placement is what lets the muscle powerfully flex the hip, bringing the thigh toward the trunk when you lift the leg or walk. The tendon mingles with iliacus to form the iliopsoas, which travels under the inguinal ligament and attaches at that lesser trochanter point.

Why the other sites don’t fit: the greater trochanter is the attachment for the gluteal muscles and deep rotators, not the psoas major. The head of the femur is not a muscle insertion site. The medial condyle of the tibia is where muscles crossing the knee insert, not where the psoas major attaches.