Colles Fascia (Perineal Fascia)

fascia perinei superficialis (Collesi)

Colles fascia (superficial perineal fascia) is the deep layer of the superficial perineal fascia, continuous with Scarpa fascia of the anterior abdominal wall and the dartos fascia of the scrotum. It is attached posteriorly to the perineal body and the posterior edge of the urogenital diaphragm, forming a closed perineal pouch anteriorly that directs urethral extravasation upward into the scrotum and anterior abdominal wall.

Anatomical Data

Boundaries & Contents

Location	Urogenital part of the perineum, deep to the skin and fat
Boundaries	Laterally: ischiopubic rami Behind: posterior border of the perineal membrane and the perineal body In front: continuous with the dartos fascia of the scrotum and Scarpa fascia of the abdominal wall
Contents	Superficial perineal pouch beneath it: ischiocavernosus, bulbospongiosus, superficial transverse perineal muscles, and the crura and bulb of the penis or clitoris

Biomechanics

Function & Actions

Forms the superficial boundary of the superficial perineal pouch, so that urine from a ruptured spongy urethra spreads into the scrotum, penis and lower abdominal wall but not into the thighs or the anal region.

Clinical Relevance

Clinical Notes

Colles fascia is critical in urethral trauma management. Rupture of the bulbar urethra causes urinary extravasation to track in the plane deep to Colles fascia, producing the characteristic butterfly bruising of the perineum and scrotal/penile swelling. The fascia prevents posterior spread but allows upward tracking under Scarpa fascia. In hypospadias repair and perineal reconstruction, Colles fascia provides the vascularised dartos fascia used for subcoronal interposition.

Pathology

Common Injuries & Conditions

Urethral Rupture with Colles Fascia Extravasation

Bulbar urethral rupture causing urine extravasation in the superficial perineal pouch beneath Colles fascia producing butterfly perineal bruising and scrotal swelling, managed by suprapubic catheter diversion and delayed urethroplasty.

Explore

More in Pelvis & Hip

Browse all of Pelvis & Hip →