Renal Fracture
Renal Laceration
- Incidence
- Up to 10% of injuries coming to emergency room
with blunt trauma
- Cause
- Motor vehicle accident
- Contact sports
- Falls and fights
- Less often penetrating wounds
- Mechanism
- Direct blow (>80%) frequently compressed and
often lacerated by lower ribs
- Acceleration-deceleration injuries can produce
renal artery tears
- Associated with other organ injury in 20% of
cases
- Signs and symptoms
- >95% hematuria
- 25% of patients with gross hematuria have
significant injuries
- But, 24% of patients with renal pedicle
injury have no hematuria
- Only 1-2% with
microhematuria have a severe renal injury
- Types of injuries
|
CT Classification of Renal Trauma |
|
CT Grade |
Injury |
Usual Treatment |
|
Grade I |
Superficial cortical laceration, contusion and/or
perirenal hematoma |
Observation |
|
Grade II |
Deep corticomedullary laceration involving the
collecting system |
Observation or surgery |
|
Grade III |
Renal crush injury and/or main vascular pedicle injury |
Surgery |
|
Grade IV |
Injury of the renal pelvis or the ureteropelvic
junction |
Surgery |
- Renal contusion
- Superficial cortical laceration (75-85%)
- Small cortical laceration without calyceal
disruption
- Complete cortical laceration
- Fracture communicating with calyceal system
(10%)
- Extraluminal contrast material
- Separation of renal poles or fracture
Contrast-enhanced CT of the mid-abdomen reveals a linear zone of low
attenuation
through the left kidney with surrounding perinephric stranding
characteristic of a deep renal laceration
- Crush injury
- Usually involves injury to the renal
vascular pedicle (5%)
- Multiple separate renal fragments
- Lack of enhancement of part or all of
kidney
- Extraluminal contrast material
- Subcapsular hematoma
- Imaging Findings
- Focal patchy areas of decreased enhancement /
striated nephrogram = contusion
- Irregular linear hypodense parenchymal areas =
renal laceration
- Laceration connecting two cortical surfaces =
fracture
- Multiple separated renal fragments ± perfusion
= shattered kidney
- Superficial crescentic hypodense area
compressing adjacent parenchyma = subcapsular hematoma
- Subcapsular / perinephric hematoma usually
proportional to extent of injury
- Wedge-shaped perfusion defect = segmental
arterial injury
- Diffuse non-perfusion of kidney =
devascularized kidney
- Persistent nephrogram on delayed scans = renal
vein thrombosis
|
Injury |
How do you recognize it |
|
Contusion (75-80%) |
focal patchy areas of
decreased enhancement |
|
Laceration |
irregular linear hypodense
parenchymal areas |
|
Fracture |
laceration connecting two
cortical surfaces |
|
Crush injury |
multiple separated renal
fragments ± perfusion |
|
Calyceal or pelvic injury |
Extraluminal contrast |
|
Vascular pedicle injury |
Wedge-shaped or diffuse
non-perfusion of kidney |
|
Subcapsular hematoma |
superficial crescentic
hypodense area compressing adjacent parenchyma |
