In a male patient with a bulbar urethral injury from a straddle injury, urine extravasation is confined by Colles' fascia. Into which space does the urine track SUPERIORLY if Colles' fascia is intact?

• A Ischioanal (ischiorectal) fossa
• B Superficial perineal pouch and then upward deep to Scarpa's fascia of the anterior abdominal wall ✓
• C Retropubic space of Retzius
• D Lateral thigh deep to fascia lata

Explanation

Colles' fascia (superficial perineal fascia) is the superficial fascia of the urogenital triangle; it is continuous with Scarpa's fascia of the anterior abdominal wall. When the urethra ruptures below the urogenital diaphragm, urine tracks into the superficial perineal pouch (between Colles' fascia and the perineal membrane) and then extends along the same fascial plane upward, deep to Scarpa's fascia, onto the anterior abdominal wall and scrotum/penis. Urine cannot track laterally into the thigh because Colles' fascia fuses with the deep fascia of the thigh lateral to the pubic arch, and it cannot enter the ischioanal fossa because it is restricted posteriorly by the transverse perineal muscles.

Reference: BD Chaurasia's Human Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.