The Medial Femoral Circumflex Artery (a. circumflexa femoris medialis; internal circumflex artery) arises from the medial and posterior aspect of the profunda, and winds around the medial side of the femur, passing first between the Pectineus and Psoas major, and then between the Obturator externus and the Adductor brevis. At the upper border of the Adductor brevis it gives off two branches: one is distributed to the Adductores, the Gracilis, and Obturator externus, and anastomoses with the obturator artery; the other descends beneath the Adductor brevis, to supply it and the Adductor magnus; the continuation of the vessel passes backward and divides into superficial, deep, and acetabular branches.
The superficial branch appears between the Quadratus femoris and upper border of the Adductor magnus, and anastomoses with the inferior gluteal, lateral femoral circumflex, and first perforating arteries (crucial anastomosis).
The deep branchruns obliquely upward upon the tendon of the Obturator externus and in front of the Quadratus femoris toward the trochanteric fossa, where it anastomoses with twigs from the gluteal arteries.
The acetabular branch arises opposite the acetabular notch and enters the hip-joint beneath the transverse ligament in company with an articular branch from the obturator artery; it supplies the fat in the bottom of the acetabulum, and is continued along the round ligament to the head of the femur.