Inferior gluteal artery

The inferior gluteal artery, the larger of the two terminal branches of the anterior trunk of the internal iliac artery, is distributed chiefly to the buttock and back of the thigh. It passes down on the sacral plexus of nerves and the Piriformis, behind the internal pudendal artery, to the lower part of the greater sciatic foramen, through which it escapes from the pelvis between the Piriformis and Coccygeus. It then descends in the interval between the greater trochanter of the femur and tuberosity of the ischium, accompanied by the sciatic and posterior femoral cutaneous nerves, and covered by the Gluteus maximus, and is continued down the back of the thigh, supplying the skin, and anastomosing with branches of the perforating arteries.   

Inside the pelvis it distributes branches to the Piriformis, Coccygeus, and Levator ani; some branches which supply the fat around the rectum, and occasionally take the place of the middle anorectal artery; and vesical branches to the fundus of the bladder, vesiculæ seminales, and prostate. 

Outside the pelvis it gives off the following branches:

• The muscular branches supply the Gluteus maximus, anastomosing with the superior gluteal artery in the substance of the muscle; the external rotators, anastomosing with the internal pudendal artery; and the muscles attached to the tuberosity of the ischium, anastomosing with the posterior branch of the obturator and the medial femoral circumflex arteries.  

•  The coccygeal branches run medialward, pierce the sacrotuberous ligament, and supply the Gluteus maximus, the integument, and other structures on the back of the coccyx. 

•  The arteria comitans of sciatic nerve is a long, slender vessel, which accompanies the sciatic nerve for a short distance; it then penetrates it, and runs in its substance to the lower part of the thigh.

• Thea anastomotic branch is directed downward across the external rotators, and assists in forming the so-called crucial anastomosis by joining with the first perforating and medial and lateral femoral circumflex arteries.  

•  The articular branch, generally derived from the anastomotic, is distributed to the capsule of the hip-joint. 

•  The cutaneous branches are distributed to the skin of the buttock and back of the thigh.