This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urethra and penis, Subject name: Surgery
A 32-years old man with pelvic fracture is in urinary retention with blood at the external urinary means. Retrograde urethrogram shows prostatomembranous disruption. The most appropriate immediate treatment is: 
Select and explain. 
A. Urethral catheterization, B. Exploration and repair of urethra, C. Suprapubic cystostomy, D. Perineal urethrostomy
C: Suprapubic cystostomy
Answer: C: Suprapubic cystostomy 
Explanation: Posterior Urethral injury- Posterior urethra is located in the pelvis and is fixed.- In cases of pelvic fracture- posterior urethra is more prone for injury.- Most common site of injury - bulbomembranous junction. Bulbar Urethral Injury Membranous Urethral Injury More common Less common Direct blow to the perineum (Straddle Injury) Blunt pelvic trauma with fracture pelvis Retention of urine Retention of urine Blood at urethral meatus Blood at urethral meatus Perineal hematoma Pelvic Hematoma Normal prostate High Lying prostate Superficial extravasation Deep extravasation - Gold standard Treatment for suspection of Urethral injuries- Suprapubic cystostomy - Delayed repair can be done after 3 months.- In emergency, surgical repair should not be attempted due to increased risk of stricture and incontinence.- Repeated urethral catheterization can conve paial tear to complete tear.