Rupture of the kidney

Trauma to the kidney may result in:

• contusion of the kidney parenchyma
• tearing of the capsule and parenchyma, with bleeding
• subcapsular haematoma formation
• avulsion of the kidney from its pedicle

Notes:

• renal trauma may be classified as closed, i.e. blunt injury, which in 80% of patients is usually treated conservatively, or open, i.e. penetrating injury, which is treated surgically in all cases
  • a blunt object damaging the kidney directly or indirectly causes closed injuries:
    • (i) direct causes; injury through the integument of the lumbar region or anterior and lateral abdominal region, e.g. after a blow from a fist or knee, a kick, sporting accidents, crushing, burying or road accidents
    • (ii) indirect causes; factors which cause sudden displacement of the kidney, its collision with the ribs or spine, ureteric tear, pedicle tear, abrupt bending of the kidney in the long axis (e.g. fall from a height) or lifting a heavy object
  • in penetrating injuries there is an obvious suspicion that the organ is damaged, whereas closed injuries are most frequently associated with multiple organ damage
• renal trauma can also be divided into:
  • small or mildly extensive, e.g. renal contusion, renal rupture with preservation of the capsule, i.e. a subcapsular haematoma, renal rupture communicating with the efferent system (with preservation of the capsule, i.e. 'pseudohydronephrosis'), rupture of the fibrous capsule of the kidney, and single renal rupture with opening of the calyces into the perirenal space
  • large or extensive kidney injuries include multiple renal ruptures with opening of the calyces into the perirenal space, avulsion of the renal pole, fragmentation of the kidney, i.e. crushing, usually with an injury to the neighbouring organs, injury to the pelvis or ureteric tear, injury to the renal vein or artery, and mixed injury to the pelvicalyceal system and renal parenchyma combined with pedicle injury