Trauma

TraumaHigh-yieldUpdated Jun 2026 · 14 min

Renal Trauma

Epidemiology / Pathogenesis

Most commonly injured GU organ in trauma
Prone to deceleration injury (falls, MVC) — kidney fixed only by renal pelvis + vascular pedicle
Pediatric kidney more susceptible — ↓ protective mechanisms: pliable thoracic cage, weaker abdominal muscles, less perirenal fat, lower abdominal position

History / Physical Exam

Extent of deceleration = most important info in blunt injury
Anterior to axillary line → hilum/pedicle injury; posterior → parenchymal injury
Exam findings (5): flank hematoma, abdominal/flank tenderness, rib fractures, hematuria, penetrating injury to low thorax/flank
- Ipsilateral rib fracture → 3× risk of significant renal trauma
- Degree of hematuria does not correlate with injury severity — don't use as sole determinant

Imaging — indications

Gross hematuria
Microscopic hematuria + SBP <90 mmHg
Mechanism concerning for renal injury (rapid deceleration, blow to flank)
Exam findings concerning for renal injury (rib fracture, flank ecchymosis)
Penetrating injury of abdomen/flank/lower chest
Pediatric patient with microscopic hematuria

Imaging — modality

CT abdomen/pelvis with IV contrast + immediate AND delayed images
Children → US may be used, but CT preferred
OR without prior CT → intraop one-shot IVP (2 mL/kg bolus, single image at 10–15 min) to confirm contralateral functioning kidney
Major CT limitation: cannot define renal venous injury → medial hematoma suggests venous injury (no modality reliably diagnoses)

CT findings suspicious for significant injury (6)

Medial laceration
Medial hematoma (vascular pedicle injury)
Medial urinary extravasation (renal pelvis / UPJ injury)
Hematoma >3.5 cm
Lack of parenchymal enhancement (main renal artery injury)
Active intravascular contrast extravasation (brisk arterial bleed)

Fluid collection density: Hematoma >30 HU | Urinoma 0–20 HU | Abscess = rim enhancement (rare post-trauma)

AAST Renal Injury Scale

Grade	CT criteria
I	Subcapsular hematoma and/or parenchymal contusion, no laceration
II	Perirenal hematoma confined to Gerota; laceration ≤1 cm, no urinary extravasation
III	Laceration >1 cm without collecting system rupture/extravasation; OR vascular injury (pseudoaneurysm/AVF) or active bleed contained within Gerota
IV	Laceration into collecting system with urinary extravasation; OR renal pelvis laceration / complete UPJ disruption; OR active bleed beyond Gerota; OR segmental vein/artery injury; OR segmental/complete infarction (thrombosis, no active bleed)
V	Main renal artery/vein laceration or hilar avulsion; OR devascularized kidney with active bleed; OR shattered kidney

Advance one grade for bilateral injury up to grade III

Management

Shift from operative exploration → non-operative management in vast majority
Non-op of blunt injury firmly established; penetrating + high-grade remains debatable

Hemodynamically stable → non-invasive management

Close hemodynamic monitoring, bed rest, ICU admission, blood transfusion (when indicated), imaging (when indicated)
Follow-up CT (after 48 h) indicated for (2): clinical signs of complications (fever, worsening flank pain, ongoing blood loss, distention); deep lacerations (Grade IV–V)
- Grade I–III → low complication risk, routine follow-up CT not advised
Risk factors for bleeding / need for intervention in grade III–IV (3): medial hematoma; hematoma >3.5–4 cm; vascular contrast extravasation
Delayed bleeding can occur up to weeks later, usually within 21 days

Hemodynamically unstable → immediate intervention (surgery OR angioembolization)

Immediate intervention if large perirenal hematoma (>4 cm) and/or vascular extravasation with deep/complex laceration (AAST III–V)
Segmental vessel bleeding → angioembolization (effective, minimally invasive)
Unstable despite resuscitation → OR, not angiography
WSES/AAST 2019: non-op for all stable/stabilized; isolated urinary extravasation is NOT an absolute contraindication to non-op

Post-embolization syndrome — self-limiting; in 10% presents with fever, pain, ileus

Surgical management

By transabdominal approach
- Small bowel mobilized outside surgical field to expose mid-peritoneum
- Incision above the IMA to expose renal veins
- Secure renal vein & retract cephalad to expose renal artery beneath it
- Then secure renal artery
- For large hematoma that may obscure vision → use IMV as a landmark to incise medially
- After securing the renal vessels, the kidney is exposed
- Left kidney exposure → Mattox maneuver
- Right kidney exposure → Cattell maneuver
Limited debridement; suture ligation of bleeders; watertight collecting-system closure; reapproximate parenchyma; omental/Gerota flap coverage; liberal drains
Major renovascular injury + 2 kidneys → speedy nephrectomy (vascular repair salvage rates poor)
Damage control: pack kidney, return in ~24 h after ICU stabilization (cold/acidotic/coagulopathic)
Unstable + no damage control option → immediate total nephrectomy

Urinary extravasation

Persistent extravasation → urinoma, perinephric infection, renal loss (rare)
Stable + no renal pelvis/proximal ureteral injury suspected → observe (grade IV parenchymal/forniceal extravasation resolves spontaneously >90%)
Intervention indications (4): suspected renal pelvis / proximal ureteral avulsion (large medial urinoma, contrast extravasation without distal ureteral contrast); enlarging/purulent/complex urinoma; complications (fever, infection, pain, ileus, fistula); continued extravasation
Options: ureteral stent (preferred) ± Foley; percutaneous urinoma drain / nephrostomy

Hypertension post-trauma

Rare early, can occur later. Mechanisms (4): renovascular stenosis/occlusion; Page kidney (parenchymal compression by blood/urine); post-trauma AVF; ureteral/UPJ obstruction
RAAS stimulated by partial ischemia. Treat: antihypertensives, observation, rarely nephrectomy

Ureteral Trauma

Epidemiology / Pathogenesis

Rare — 1% of urologic injuries
Causes (3): iatrogenic; external violence (high-speed blunt); penetrating (stab/GSW)
Iatrogenic procedures: hysterectomy 54%, colorectal 14%, ovarian tumor 8%

Intraoperative ureter assessment

Direct inspection (for high velocity / thermal injury); retrograde pyelography

Endoscopic / iatrogenic

Ureteroscopy over a wire into renal pelvis
Perforation recognized → stop procedure, place stent
Aortoiliac/aortofemoral bypass manipulation → hydronephrosis in 12–20% (benign; steroids if symptomatic)
Prophylactic preop stenting does NOT reduce injury risk (RCT, gyn surgery)

Diagnosis

Imaging: contrast CT with 10-min delayed films (stable, not going directly to laparotomy)
Findings (4): contrast extravasation; lack of distal ureteral contrast; ipsilateral delayed pyelogram; ipsilateral hydronephrosis
No preop imaging → direct inspection at laparotomy

AAST Ureter Injury Scale

Grade	Criteria
I	Contusion/hematoma, no devascularization
II	Laceration <50% transection
III	Laceration ≥50% transection
IV	Complete transection, <2 cm devascularization
V	Avulsion, >2 cm devascularization

Advance one grade for bilateral injury up to grade III

Management

Stable → look for the time window [less than 7 days or more than 7 days]

Early recognition (<7 days):
- URS: perforation → stent 4–6 wks / avulsion → immediate repair
- Thermal / high-velocity contusion → debridement UU
- Small contusion → stent 4–6 wks
- Major pelvic → reimplant ± psoas hitch (6–10 cm) / (4–5 cm) / Boari flap (12–15 cm)
- Major abdominal → reimplant / UU 2–3 cm / TUU
- UPJ → UP (pyeloplasty)
- Loss of entire ureter → ileal ureter / nephrectomy / autotransplant
Late recognition (>7 days):
- Retrograde stent; if failed → antegrade stent; if failed → PCN → then wait 6 wks for final management

Unstable → temporary urinary drainage, delayed definitive repair (4 options)

Ureteral stent (internal double-J or exteriorized single-J)
Short observation, reoperate when stable (~24 h)
Exteriorize the ureter
Tie off ureter (long silk for ID) + percutaneous nephrostomy

Special scenarios

Contusion → stent; resection + primary repair if severe/large contusion or GSW-related (excise devitalized tissue + adjacent normal ureter for blast effect; spatulate ~5–6 mm at 180° apart)
Delayed diagnosis → stent; if fails/impossible → percutaneous nephrostomy + delayed repair
- Immediate repair if: injury near closed viscus (bowel/vagina); patient re-explored for other reasons
Endoscopic injury → stent ± nephrostomy
Ureterovaginal fistula → stent (success 64–100%); failures → reimplant ± Boari/psoas hitch or TUU
Ligation → remove ligature, observe viability; uncertain → ureteroureterostomy or reimplant
Ureteroarterial fistula → catastrophic, diagnose + treat immediately (life-threatening hematuria)

Principles of repair

Mobilize sparing adventitia; debride minimally until edges bleed (esp. GSW)
Spatulated, tension-free, stented, watertight anastomosis — absorbable suture + retroperitoneal drainage
Retroperitonealize repair; omental interposition for complex/blast/vascular cases
Non-tunneled widely spatulated ureteroneocystostomy

Post-op principles:

Remove Foley before drain
Foley 24–48 hr post-op
Remove drain 1 day after Foley if no high output
Remove stent 4–6 wks post-op
Re-imaging 4–8 wks after stent removal

Bladder Injury

Background / Pathogenesis

Usually pelvic fracture
Burst injury at dome from blow to full bladder; penetrating
Bladder protected by bony pelvis; blunt injury rarely isolated
83–95% of bladder injuries have pelvic fracture; only 5–10% of pelvic fractures have bladder injury
Iatrogenic → obstetric/gyn most common in open surgery

AAST Bladder Injury Scale

Grade	Criteria
I	Contusion / intramural hematoma; partial-thickness laceration
II	Extraperitoneal laceration <2 cm
III	Extraperitoneal >2 cm OR intraperitoneal <2 cm
IV	Intraperitoneal >2 cm
V	Intra- or extraperitoneal laceration into bladder neck or ureteral orifice (trigone)

Clinical indicators (12)

Gross hematuria = most common indicator
Lower abdominal bruising, abdominal distention, suprapubic pain, guarding/rigidity, inability to void, low urine output, diminished bowel sounds
Pubic symphysis diastasis; obturator ring fracture displacement >1 cm
↑ Creatinine + BUN (peritoneal urine absorption); urinary ascites (intraperitoneal low-density free fluid)

Imaging — indications

Absolute: gross hematuria + pelvic fracture / also penetrating injury with any hematuria (absolute)
Relative: gross hematuria + concerning mechanism; pelvic ring fracture + clinical indicators
Pelvic fracture alone does not warrant bladder imaging

Imaging — modality

Retrograde cystography (CT or plain film — similar sensitivity/specificity); determines presence + intra- vs. extraperitoneal
Fill to 300–350 mL (or discomfort); false-negatives reported at only 250 mL
CT cystography → dilute contrast 1:6 (mandatory, avoid scatter)
Plain film → 2 views (max fill + post-drainage); drainage film not needed for CT
Extraperitoneal = flame-shaped contrast collection in pelvis
Intraperitoneal = contrast outlines bowel loops / peritoneal cavity
Amount of extravasation ≠ extent of injury

Management

Blood at meatus / catheter won't pass → RUG first (urethral injury coexists in 10–30% of bladder ruptures)

Extraperitoneal (uncomplicated) → catheter drainage

Large-bore (22-Fr) Foley × 2–3 weeks
Open repair if:
- Bone spicules exposed in lumen
- Rectal injury (concurrent)
- Bladder neck injury
- ORIF of pelvic fracture (reduce hardware infection)
- Vaginal injury (concurrent)
- Abdominal injury repair (do bladder at same time)
- penetrating/iatrogenic non-urologic injury
- inadequate drainage/clots

Intraperitoneal → prompt surgical repair

Follow-up cystography 7–10 days post-op for complex repairs

Bladder perforation from cystoscopy procedure:

Do cystogram first
Extraperitoneal → bladder drainage
Intraperitoneal: small → bladder drainage
Repair if → large, suspected intra-abdominal injury, protruding into bladder, ileus, peritonitis, significant bleeding, or urethral catheter clogging

Urethral Injury

Classification / Pathogenesis

Partial or complete disruption
Male: posterior (membranous) vs. anterior (penile/bulbar)
Posterior → almost exclusively pelvic fracture
- Bulbomembranous junction most vulnerable (posterior urethra adherent to pubis via UG diaphragm + puboprostatic ligaments)
Anterior → blunt (straddle = urethra crushed against pubis) or penetrating; bulbar urethra most common

Clinical indicators (5)

Blood at the meatus = most common
Inability to urinate; perineal/genital ecchymosis
Male: high-riding prostate; Female: labial edema / vaginal blood
Buck's fascia disrupted → "butterfly" hematoma (urine below Dartos into scrotum, up abdominal wall below Scarpa's; posterior limit = Colles')

Imaging

Retrograde urethrogram (RUG) — perform immediately when injury suspected
Avoid blind catheter passage before RUG
Technique: oblique position (bottom leg flexed); 12-Fr Foley/syringe in fossa navicularis; penis on traction; inject 20–25 mL undiluted water-soluble contrast
If Foley already placed + meatal blood → pericatheter RUG (3-Fr/angiocath in fossa navicularis)
Female suspected urethral injury → urethroscopy (in lieu of RUG)

Management — general

Immediate goal = secure bladder drainage
Partial disruption (contrast passes proximally) → single gentle catheter attempt by experienced team

Male — posterior (PFUI) → immediate suprapubic tube, delayed repair

SPC = gold standard (14-Fr or larger; US/fluoro/18-G needle aspiration to localize displaced bladder); safe even with ORIF
Primary realignment = advance catheter across rupture; may ↓ stricture severity but longer course/more procedures; maintain SPC while awaiting PFUI resolution
- ED setting inappropriate for primary realignment; avoid prolonged endoscopic attempts
Immediate sutured repair → unacceptably high ED + incontinence rates (avoid)
Delayed reconstruction: most develop obliterative stricture → open posterior urethroplasty at ≥3 months (ambulatory, injuries stabilized; rupture defect = fibrosis-filled, stable at 3 mo)
- Get cystogram + RUG before repair
- Open perineal anastomotic urethroplasty (excise fibrosis + distal mobilization + primary transecting anastomosis) = best long-term outcomes; limit lithotomy ≤5 h
Complications (3): stricture, ED (from the pelvic fracture), incontinence — follow ≥1 year; recurrent stenosis post-urethroplasty 5–15%; incontinence after reconstruction <4%

Male — anterior

Contusion / incomplete → urethral catheter alone
Straddle → suprapubic tube (or primary realignment if mild), delayed repair
- Immediate operative repair contraindicated (indistinct injury border); high stricture rate → surveillance
- Delayed anastomotic urethroplasty = procedure of choice for obliterated bulbar urethra
Penetrating → prompt primary repair (spatulated primary repair > delayed reconstruction — contrast to PFUI/straddle); not if unstable / no expertise / extensive tissue loss

Female → immediate primary repair or realignment over catheter

Avoids urethrovaginal fistula / obliteration; delayed repair problematic (urethra ≈4 cm, too short to mobilize once scarred)

External Genitalia Injury

Penile Fracture

Definition: disruption of tunica albuginea with rupture of corpus cavernosum
Mechanism: most often vigorous intercourse (penis strikes perineum/pubis → buckling)
Bilateral corporal tears in 10%

Diagnosis — reliable on Hx + exam

"Cracking/popping/snapping" + immediate detumescence; eggplant deformity (Buck's intact) or butterfly (Buck's disrupted); palpable fracture line; deviates away from tear
Imaging only if equivocal: US (preferred — rapid, cheap, accurate); penile MRI = most accurate
Urethral evaluation (RUG/urethroscopy) — urethral injury in 10–22% (more with bilateral corporal injury); indications = blood at meatus, gross hematuria, inability to void

Management → prompt exploration + surgical repair

Benefits (7): faster recovery, ↓ morbidity, ↓ complications, ↓ ED, ↓ long-term curvature, ↓ cavernosal diverticulum, ↓ chronic pain
Delay up to 7 days does not adversely affect repair
Approach: distal circumcising/degloving (uncertain location — exposes all 3 compartments) OR incision at the site of injury OR ventral midline
Repair tunica with interrupted 2-0/3-0 absorbable (Vicryl); artificial erection (saline + methylene blue) to localize/test
Urethral injury: partial → oversew over catheter; complete → debride, mobilize, tension-free repair over catheter
Post-op: broad-spectrum antibiotics + 1 month sexual abstinence

Penile Penetrating / Other

GSW: immediate exploration, copious irrigation, excise foreign matter, antibiotic prophylaxis, surgical closure
- Low-velocity urethral injury → primary closure; high-velocity / shotgun → staged repair + SP diversion
Bites: dog → irrigation, debride, primary closure with drain + broad-spectrum antibiotics (amox/clav, cefoxitin, clindamycin+cipro) + tetanus/rabies; human bites → do NOT close primarily
Amputation: "double bag" — distal penis rinsed in saline, wrapped in saline gauze, sealed bag in outer bag with ice; transfer to microsurgical center
- Reimplant viable: <16 h cold OR <6 h warm ischemia; macrovascular repair preserves erectile/urethral function, microvascular needed for skin + sensation
Zipper injury (boys/intoxicated): penile block, lubricate with mineral oil, single unzip attempt; failing that → bone cutter

Testicular Trauma

Consider rupture in all blunt scrotal trauma (rupture of tunica albuginea)
Hematoma degree does not correlate with injury
US reliable for blunt (limited for penetrating): heterogeneous parenchyma + tunica albuginea contour disruption
- Normal/equivocal US should not delay exploration if exam suggests rupture

Scrotal exploration indications (6)

Imaging findings of rupture; equivocal imaging but suspected rupture; large hematoma (explore + drain even without rupture → prevent pressure necrosis/atrophy); clear physical findings; penetrating scrotal injury (>50% have rupture); significant hematocele (up to 80% from rupture)
GSW → 30% injure both testes → consider contralateral exploration; ligate injured vas with non-absorbable suture, delayed reconstruction

Repair

Early exploration + repair benefits (6): ↑ salvage, ↓ ischemic atrophy, ↓ infection, preserved fertility/hormonal function, ↓ convalescence, faster return
Salvage >90% if repair within 72 h; orchiectomy 3–8× higher with delayed surgery
Technique: transverse scrotal incision; remove necrotic/extruded tubules; close tunica albuginea with small absorbable suture; tunica vaginalis flap/graft for large defects; orchiectomy if non-salvageable

Genital Skin Loss

Most common cause of extensive loss = Fournier gangrene (polymicrobial necrotizing infection)
Exploration + limited debridement (genital skin well vascularized, marginal tissue may survive); multiple OR trips before definitive reconstruction
Burn + urethral catheter → remove after 72 h (prevent urethral slough/fistula)
Penile reconstruction: thick (0.012–0.015"), non-meshed split-thickness graft (meshed contracts); excise residual subcoronal skin (avoids lymphedema); foreskin flap best for small distal loss; shaft grafts never regain normal sensation (glans sensation preserves function)
Scrotal reconstruction: defects up to 60% closed directly; meshed STSG preferred; extensive → testes in thigh pouches/vacuum dressing (not in active infection)