Dissection of male pelvis from a lateral approach

Obturator internus muscle and nerve supply, medial view

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Image #172-7

Dissection of male pelvis from a lateral approach

Obturator internus muscle and nerve supply, medial view

The pelvic diaphragm has been removed from the specimen and the obturator fascia has been stripped away.

1. Iliac branch of iliolumbar artery
2. Iliac crest
3. Obturator internus muscle
4. Obturator nerve
5. Iliopsoas muscle
6. Obturator artery
7. Superior pubic ramus
8. Pubic symphysis (sectioned)
9. Pubic arcuate ligament
10. Inferior pubic ramus
11. Ramus of ischium
12. Ramus communicans (to sacral nerve I)
13. Lumbosacral trunk
14. Sacral nerve I (ventral ramus)
15. Sympathetic trunk (pointer on ganglion)
16. Anterior (pelvic) sacral foramen (pointer indicates opening within sacral canal exposed by cutting through sacrum)
17. Rami communicantes
18. Left pointer: Sacral nerve II Right pointer: Sacral nerve III
19. Sacrum
20. Piriform muscle
21. Inferior gluteal artery
22. Sacral nerve IV
23. Upper pointer: Inferior rectal nerve Lower pointer: Pudendal nerve
24. Upper pointer: Branch of sacral nerve III to posterior femoral cutaneous nerve Lower pointer: Sciatic nerve
25. Nerve to obturator internus muscle (indicated in two places)
26. Coccygeus muscle
27. Location of ischial spine
28. Coccyx
29. Internal pudendal artery
30. Sacrotuberous ligament (cut off at attachment)
31. Ischial tuberosity