It leaves the pelvis in front of the obturator externus and descends in front of the adductor brevis, and behind the pectineus and adductor longus; at the lower border of the latter muscle it communicates with the saphenous branches of the femoral nerve, forming a kind of plexus.
12.
The posterior side of the hip exhibits primarily hip extension, dealing with the muscles : gluteus maximus, hamstring muscles ( biceps femoris, semitendinosus, semimembranosus ), and the six deep external rotators ( piriformis, obturator externus, obturator internus, gemellus superior, gemellus inferior, and quadrates femoris ).
13.
The " medial surface ", of much less extent than the lateral, presents at its base a deep depression, the trochanteric fossa ( digital fossa ), for the insertion of the tendon of the obturator externus, and above and in front of this an impression for the insertion of the obturator internus and superior and inferior gemellus muscles.
