In a 45-year-old man with a straddle injury presenting with a butterfly perineal hematoma, swollen penis and scrotum, and blood at the urethral meatus, what is the most likely site of urethral injury?

Bulbar (Anterior) Urethra

In a 45-year-old man with straddle injury presenting with butterfly perineal hematoma, penile and scrotal swelling, and blood at the urethral meatus, the injury is most likely located in the bulbar urethra (anterior urethra).

Clinical Reasoning

The constellation of findings points definitively to an anterior urethral injury, specifically at the bulbar segment:

• Butterfly perineal hematoma: This classic pattern occurs when Buck's fascia is disrupted, allowing blood to spread into the perineum, scrotum, and penis in a characteristic butterfly distribution 1

• Straddle mechanism: The bulbar urethra is crushed between the pubic bones and a fixed object (bicycle bar, fence, etc.), making it the anatomically vulnerable site in this injury pattern 1

• Blood at meatus: Present in 37-93% of urethral injuries, this finding mandates immediate investigation but doesn't localize the injury alone 1

Anatomic Distinction

The male urethra divides into:

• Posterior urethra: Membranous and prostatic portions, almost exclusively injured by pelvic fractures (1.5-10% of pelvic fractures) 1
• Anterior urethra: Penile and bulbar portions, injured by straddle trauma or penetrating mechanisms 1

The absence of pelvic fracture history and presence of butterfly hematoma essentially excludes posterior urethral injury 1.

Immediate Management Algorithm

1. Do NOT attempt blind catheterization - this risks converting partial injury to complete disruption 1

2. Perform retrograde urethrography immediately to confirm diagnosis and assess injury severity (partial vs. complete disruption) 1, 2

3. Establish urinary drainage promptly:

   • Suprapubic catheter placement is preferred for straddle injuries 1
   • Single attempt at well-lubricated catheter placement by experienced clinician acceptable only if partial injury confirmed 1

4. Avoid immediate surgical repair - the injury border is indistinct acutely, making immediate debridement or repair contraindicated 1

Critical Pitfalls

• Stricture formation is extremely high after straddle injuries, approaching near-universal rates 1. All patients require surveillance with uroflowmetry, retrograde urethrogram, and/or cystoscopy during the first year 1

• Delayed urethroplasty (typically >3 months) after accurate assessment of injury extent is the definitive treatment 3

• Endoscopic realignment should be attempted before considering surgery if conservative drainage fails 3

The butterfly hematoma pattern is pathognomonic for Buck's fascia disruption with anterior urethral injury, distinguishing this from posterior urethral injuries that present with high-riding prostate, inability to void, and pelvic fracture 1, 4, 2.