Colles' Fascia

Colles' fascia is the membranous layer of the superficial perineal fascia. It lies deep to the fatty layer (Camper’s fascia) and superficial to the superficial perineal muscles. It is continuous with other membranous fasciae of the body, including Scarpa’s fascia of the abdominal wall and Dartos fascia of the scrotum or labia. Colles’ fascia plays an important role in compartmentalizing the perineal region and preventing the spread of infections or fluids between adjacent areas.

Structure

Colles’ fascia is a tough, fibrous, membranous layer made of dense connective tissue. It forms the floor of the superficial perineal pouch, enclosing the superficial perineal muscles and erectile bodies. It is firmly attached to surrounding fascial and bony landmarks, which help define the boundaries of the superficial perineal space.

Attachments

• Posterior: Posterior edge of the perineal membrane (fuses with it)
• Lateral: Ischiopubic rami
• Anterior: Continuous with Scarpa’s fascia (abdominal wall) and Dartos fascia (scrotum/labia)

Continuities

• Continuous with:
  • Scarpa’s fascia in the anterior abdominal wall
  • Dartos fascia of the scrotum or labia
  • Penile fascia (in males)

Location

Colles’ fascia is located in the perineum within the urogenital triangle, deep to Camper’s fascia and superficial to the perineal membrane and muscles. It forms the inferior boundary of the superficial perineal pouch.

Function

• Compartmentalization: Defines the superficial perineal pouch by forming its floor
• Barrier to fluid spread: Prevents urine or blood from extravasating into the thigh or anal triangle
• Support: Helps maintain positioning of superficial perineal muscles and erectile bodies

Clinical Significance

• Urethral rupture: If the spongy urethra is ruptured, urine may collect deep to Colles' fascia and spread to scrotum, penis, and anterior abdominal wall (but not into thighs)
• Surgical identification: Important landmark in perineal surgeries and abscess drainage