ABC of major trauma. Trauma of the lower urinary tract.

Mechanism of direct blunt renal trauma. An external force (F,) may crush the kidney (K) between the 12th rib and the vertebral column, or a force (F2) may crush the kidney against the paravertebral muscles (quadratus lumborum (QL) or psoas major (in position P but deleted from diagram). In the United Kingdom over 90% of renal injuries are a result of blunt abdominal trauma. Important associated injuries occur in about 40% of patients with blunt renal trauma. A high index of suspicion of a renal lesion is required in the patient with multiple injuries as the signs and symptoms of the renal trauma may be obscured by those of the concomitant injuries.