Dissection of anal triangle and ischiorectal fossae
General view of male perineum and ischiorectal fossae
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Image #173-4
Dissection of anal triangle and ischiorectal fossae
General view of male perineum and ischiorectal fossae
The membranous layer of superficial fossae (Colles' fascia) has been preserved in the urogenital triangle. In the anal triangle the ischiorectal fossae (10) have been dissected and the anal sphincter has been exposed. The irregular lunate fascia (12) has been preserved in the fossae and it is apparent that there is a continuity between this layer and Colles' fascia anteriorly. The left thigh has been sectioned slightly below the level of the trochanters of the femur.
- Medial cluneal nerves
- Coccyx (covered by periosteum and ligaments)
- Anococcygeal ligament
- Gluteus maximus muscle (portion arising from sacrotuberous ligament)
- Upper pointer: Anus Lower pointer: External anal sphincter muscle
- Inferior cluneal nerves
- Posterior perineal branches femoral cutaneous nerve
- Fascia lata
- Upper pointer: Superficial perineal fascia (Colles' fascia) Lower pointer: Scrotum
- Ischiorectal fossa (pointer indicates posterior recess of fossa)
- Left pointer: Inferior rectal nerves Right pointer: Inferior rectal artery
- Upper pointer: Lunate fascia Lower pointer: Posterior border of urogenital triangle
- Gluteus maximus muscle
- Posterior scrotal nerves
- Semimembranosus muscle
- Semitendinosus muscle
- adductor magnus muscle
- Gracilis muscle