A 45-year-old man is brought to the emergency department after a motor vehicle accident. He is unable to void and complains of a full bladder sensation. Foley catheter placement is attempted, but the procedure is aborted once resistance is encountered and the patient begins complaining of pain. A CT scan of his chest, abdomen, and pelvis shows a left hemothorax and pelvic fracture. This patient is most likely to have an injury involving which of the following portions of the urogenital tract?

Question

A 45-year-old man is brought to the emergency department after a motor vehicle accident.  He is unable to void and complains of a full bladder sensation.  Foley catheter placement is attempted, but the procedure is aborted once resistance is encountered and the patient begins complaining of pain.  A CT scan of his chest, abdomen, and pelvis shows a left hemothorax and pelvic fracture.  This patient is most likely to have an injury involving which of the following portions of the urogenital tract?

Quizplus · Accepted Answer

11ec160b_3591_9f4b_9249_9d7971801a23_MD0001_00 The presence of a pelvic fracture and inability to void despite the sensation of a full bladder is suggestive of urethral injury. Additional signs of urethral injury include the presence of blood at the urethral meatus and a high-riding, boggy prostate (caused by hematoma formation below the gland). If urethral injury is suspected, placement of a Foley catheter is contraindicated and should not be attempted as it can worsen the injury; a retrograde urethrogram should be performed first to assess urethral integrity. Urethral injuries most commonly occur in men because of their longer urethral length and are divided into anterior and posterior urethral injuries. The posterior urethra is located above the bulb of the penis, and the anterior urethra lies within the bulb and the remainder of the corpus spongiosum. The posterior urethra is further divided into the prostatic and membranous segments; the anterior urethra is divided into bulbous and penile segments. In contrast to the prostatic and bulbous segments, the membranous segment is relatively unsupported by the adjacent tissues and is the weakest point of the posterior urethra. Trauma to the pelvis severe enough to cause fracture often results in disruption of the posterior urethra at the bulbomembranous junction. (Choice A) Injury of the anterior bladder wall is common with pelvic fractures and is usually associated with extraperitoneal leakage of urine. Superior bladder wall ruptures often occur with abdominal trauma when the bladder is full and result in leakage of urine into the intraperitoneal cavity. This patient's full bladder sensation and inability to pass a Foley catheter makes a urethral injury more likely. (Choice B) The prostatic urethral segment is strengthened by the surrounding prostate tissue and thus is less likely to be damaged from a pelvic fracture. (Choice D) Although the bulbous urethral segment is reinforced by the surrounding corpus spongiosum, it is susceptible to crushing injuries when the perineum is struck forcefully (ie, straddle injury). Common mechanisms include falling on the crossbar of a bicycle or the top of a fence. (Choice E) The penile urethral segment is most commonly injured due to penetrating trauma or instrumentation. Educational objective: Injury to the posterior urethra is associated with pelvic fractures, and the anterior urethra is most commonly damaged in straddle injuries. Inability to void with a full bladder sensation, a high-riding boggy prostate, and blood at the urethral meatus are suggestive of urethral injury, particularly in the presence of a pelvic fracture. If urethral injury is suspected, placement of a Foley catheter is contraindicated. __________ References: Diagnosis and classification of urethral injuries. (http://www.ncbi.nlm.nih.gov/pubmed/16488282) Lower urinary tract injuries following blunt trauma: a review of contemporary management. (http://www.ncbi.nlm.nih.gov/pubmed/22114545)

A 45-Year-Old Man Is Brought to the Emergency Department After