Dissection of male pelvis from a lateral approach

Relation of pelvic diaphragm to urogenital diaphragm and sphincter ani externus muscle

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Image #169-2

Dissection of male pelvis from a lateral approach

Relation of pelvic diaphragm to urogenital diaphragm and sphincter ani externus muscle

The internal pudendal artery has been divided and removed. The urogenital diaphragm has been retracted downward to expose the anterior border of the levator ani muscle. The manner in which the fibers or origin of the levator ani muscle blend with the obturator fascia (4) along the lateral pelvic wall may be observed in this specimen.

1. Tendinous arch of levator ani muscle
2. Acetabulum
3. Acetabular labrum
4. Obturator fascia
5. Obturator nerve
6. Periosteum
7. Body of pubic bone (dissected)
8. Sacrospinous ligament
9. Internal pudendal artery (cut off)
10. Ischial spine
11. Coccygeus muscle
12. Perineal branch of sacral nerve IV
13. Anococcygeal ligament
14. Coccyx
15. Iliococcygeus muscle
16. Pubococcygeus muscle
17. Puborectalis muscle (15-17 make up the levator ani muscle)
18. Deep part
19. Superficial part
20. Subcutaneous part (18-20 are part of the external anal sphincter)
21. Central tendon of perineum
22. Superior fascia of urogenital diaphragm (pulled downward)
23. Urethra (opened)