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Wound in the left flank with gas in the erector spinae muscles and overlying haematoma in the subcutaneous tissues.  Note contrast leak from the muscles into soft tissues on the portal venous phase indicating active bleeding.  No obvious haematoma or contrast leak in the retroperitoneum or peritoneal cavity.  More importantly there are gas bubbles in the spinal canal (epidural) at the level of penetration (arrow).  This indicates that the spinal canal has been entered by the knife tip alerting the clinicians to the possibility of spinal injury.