AAST renal injury scale

GradeParenchymaCollecting systemVascular
Grade I Sub capsular hematoma and/or contusionNo injuryNo injury
Grade II Laceration < 1 cm in depth and into cortex, small perirenal hematoma contained within Gerota fasciaNo injuryNo injury
Grade IIILaceration > 1 cm in depth and into medulla, hematoma contained within Gerota fasciaNo injuryNo injury
Grade IVLaceration through the parenchyma into the urinary collecting systemLaceration, one or more into the collecting system with urinary extravasation.
Renal pelvis laceration and/or complete ureteral pelvic disruption		Segmental vein or artery injury.
Main renal artery or vein injury with contained hemorrhage
Grade VCompletely shattered kidneyCompletely shatteredAvulsion of renal hilum, devascularization of kidney