1 — External anal sphincter; 2 — Rectum; 3 — Inferior rectal artery; 4 — Middle rectal artery; 5 — Obturator artery; 6 — Internal pudendal artery; 7 — Inferior gluteal artery; 8 — External iliac artery; 9 — Superior gluteal artery; 10 — Internal iliac artery; 11 — Sigmoid colon; 12 — Sigmoid arteries; 13 — Superior rectal artery; 14 — Inferior mesenteric artery; 15 — Abdominal aorta; 16 — Median sacral artery; 17 — Common iliac artery; 18 — Obturator canal; 19 — Ischial spine; 20 — Obturator internus; 21 — Ischial tuberosity; 22 — Levator ani; 23 — Anus
