The perineal membrane is also known as which term?

• A. superior fascia of urogenital diaphragm
• B. inferior fascia of the urogenital diaphragm
• C. Colle's fascia
• D. perineal membrane

Answer: (B)

The perineal membrane is the inferior fascia of the urogenital diaphragm. This thick fascial sheet spans the perineal space, forming the floor of the deep perineal pouch and anchoring to the margins of the pubic bones and the ischiopubic rami. It separates the deep perineal structures from the superficial perineal space and provides a sturdy support for the muscles of the deep perineal pouch, such as the sphincter urethrae and deep transverse perineal muscles. The superior boundary of the deep perineal pouch is formed by the superior fascia of the urogenital diaphragm, not by the perineal membrane. Colles' fascia is the superficial perineal fascia and lies superficial to the perineal membrane, continuing with Scarpa's fascia in the abdominal wall, so it is a different structure.