Dissection of anal triangle and ischiorectal fossae
Course of internal pudendal artery and pudendal nerve in pudendal canal; muscles of pelvic diaphragm
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Image #173-7
Dissection of anal triangle and ischiorectal fossae
Course of internal pudendal artery and pudendal nerve in pudendal canal; muscles of pelvic diaphragm
The sacrotuberous ligament has been cut away on the left to expose the course of the internal pudendal artery and the pudendal nerve as these structures pass posterior to the ischial spine (8) to enter the pudendal canal (15). The lunate fascia has been reflected to open the entire length of the pudendal canal which extends anteriorly to the posterior border of the urogenital diaphragm. The latter is obscured by the muscles that occupy the superficial perineal space.
- Thoracolumbar fascia
- Erector spinae muscle
- Gluteus maximus muscle
- Gluteus medius muscle
- Piriform muscle
- Upper pointer: Sacrotuberous ligament (cut off) Lower pointer: Coccygeus muscle
- Inferior gluteal nerve
- Upper pointer: Internal pudendal artery (crossing ischial spine) Middle pointer: Dorsal nerve of the penis Lower pointer: Perineal nerve
- Posterior femoral cutaneous nerve
- Upper pointer: Sciatic nerve Lower pointer: Quadratus femoris muscle
- Obturator externus muscle
- Lesser trochanter
- Sacrotuberous ligament (cut off)
- Upper pointer: Inferior rectal nerve Lower pointer: Inferior rectal artery
- Left pointer: Obturator fascia Right pointer: Lunate fascia covering pudendal canal (reflected to open canal)
- Levator ani muscle
- Upper pointer: Anus Lower pointer: External anal sphincter muscle
- Superficial dorsal sacrococcygeal ligament
- Upper pointer: Coccyx (end piece) Lower pointer: Anococcygeal nerve
- Anococcygeal ligament
- Ischial tuberosity
- Sciatic nerve
- Adductor brevis muscle
- Lunate fascia at posterior border of urogenital diaphragm
- Perineal artery
- Ischiocavernosus muscle
- Bulbospongiosus muscle
- Penis