Splenic Injury

Description

• The spleen is formed by reticular and lymphatic tissue and is the largest lymph organ
• The spleen lies posterolaterally in the left upper quadrant (LUQ) between the fundus of the stomach and the diaphragm

Etiology

• The spleen is the most commonly injured intra-abdominal organ:
  • In nearly 2/3 of cases, it is the only damaged intraperitoneal structure
  • Blunt mechanisms are more common
• Motor vehicle accidents (auto–auto, pedestrian–auto) are the major cause (50–75%), followed by blows to the abdomen (15%) and falls (6–9%)
• Mechanism of injury and kinematics are important factors in evaluating patients for possible splenic injury
• Iatrogenic injuries to the spleen can result from surgical or endoscopic manipulation of the stomach, pancreas, kidney, or proximal abdominal aorta
• Splenic injuries are graded by type and severity of injury (American Association for the Surgery of Trauma [AAST] criteria):
  • Grade I:
    • Hematoma: Subcapsular, <10% surface area
    • Laceration: Capsular tear, <1 cm in parenchymal depth
  • Grade II:
    • Hematoma: Subcapsular, 10–50% surface area; intraparenchymal, <5 cm in diameter
    • Laceration: Capsular tear, 1–3 cm in parenchymal depth and not involving a trabecular vessel
  • Grade III:
    • Hematoma: Subcapsular, >50% surface area or expanding, ruptured subcapsular or parenchymal hematoma; intraparenchymal hematoma, ≥5 cm or expanding
    • Laceration: >3 cm in parenchymal depth or involving the trabecular vessels
  • Grade IV:
    • Laceration: Involving the segmental or hilar vessels and producing major devascularization (>25% of spleen)
  • Grade V:
    • Laceration: Completely shattered spleen
    • Vascular: Hilar vascular injury that devascularizes the spleen

• Poorly developed musculature and relatively smaller anteroposterior diameter increase the vulnerability of abdominal contents to compressive forces
• Rib cage is extremely compliant and less prone to fracture in children but provides only partial protection against splenic injury
• Splenic capsule in children is relatively thicker than that of an adult; parenchyma of spleen seems to contain more smooth muscle than in adults
• Significant abdominal injury occurs in only about 5% of child abuse cases but is the second most common cause of death after head injury