It is the longest bone in the human body. The greater trochanter is where the external pelvic muscles attach. The lesser trochanter is the site of attachment of the iliopsoas muscle (m. iliopsoas). Attached to the bone is the quadratus femoris (m. quadratus femoris), which is the largest muscle in the human body. The shaft of the bone is slightly convex anteriorly. The lateral condyle of the bone serves as an attachment for the popliteal muscle (m. popliteus).