Renal Injury Grading Scale

The Organ Injury Scaling (OIS) Committee’s classification of renal trauma:

Grade 1
Hematuria with normal imaging studies
Contusions
Nonexpanding subcapsular hematomas

Grade 2
Nonexpanding perinephric hematomas confined to the retroperitoneum
Superficial cortical lacerations less than 1 cm in depth without collecting system injury

Grade 3
Renal lacerations greater than 1 cm in depth that do not involve the collecting system

Grade 4
Renal lacerations extending through the kidney into the collecting system
Injuries involving the main renal artery or vein with contained hemorrhage
Segmental infarctions without associated lacerations
Expanding subcapsular hematomas compressing the kidney

Grade 5
Shattered or devascularized kidney
Ureteropelvic avulsions
Complete laceration or thrombus of the main renal artery or vein

Reference

Moore EE, Shackford SR, Pachter HL, McAninch JW, Browner BD, Champion HR, Flint LM, Gennarelli TA, Malangoni MA, Ramenofsky ML, et al. Organ injury scaling: spleen, liver, and kidney. J Trauma 1989; 29: 1664-6.