## **Core Concept**
Membranous urethral injuries are a type of lower urinary tract injury often associated with pelvic fractures. These injuries occur in the part of the urethra that passes through the urogenital diaphragm. The key to managing these injuries is early recognition of the symptoms and signs.

## **Why the Correct Answer is Right**
The correct answer can be deduced by understanding the typical features of membranous urethral injuries. Common features include blood at the urethral meatus, perineal hematoma, high riding prostate on digital rectal examination (in males), and inability to pass a urethral catheter. Option seems to be the exception as the classic description of a membranous urethral injury often involves specific signs.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Blood at the urethral meatus is a classic sign of urethral injury, including membranous urethral injuries. This is due to the disruption of the urethral mucosa and exposure of the urethral lumen to the external environment.
- **Option B:** Perineal hematoma can occur due to the injury of the membranous urethra, as it is located in a relatively fixed position within the urogenital diaphragm, making it susceptible to injury during pelvic fractures or direct blows to the perineum.
- **Option D:** Inability to pass a urethral catheter is also a feature, as the injury might cause a blockage or disruption that prevents the catheter from being inserted.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that in cases of suspected urethral injury, the initial management involves performing a retrograde urethrogram to assess the integrity of the urethra before attempting catheterization. This helps prevent further injury to the urethra.

## **Correct Answer:** .