A blunt trauma to the left upper quadrant with left shoulder pain and abdominal rigidity and rebound tenderness suggests injury to which organ?

• A. Liver
• B. Spleen
• C. Kidney
• D. Stomach

Answer: (B)

Blunt trauma to the left upper quadrant with left shoulder pain and signs of peritoneal irritation points to splenic injury. The spleen, located in the LUQ, is highly vascular and when injured blood can irritate the diaphragm. That diaphragmatic irritation often manifests as referred pain to the left shoulder, a presentation known as Kehr’s sign. Abdominal rigidity and rebound tenderness indicate irritation of the peritoneum from internal bleeding, which aligns with splenic rupture or laceration. Among the organs listed, the spleen is the one in the left upper quadrant and most prone to this pattern of injury; the liver is in the right upper quadrant, the kidneys are retroperitoneal and less likely to cause diaphragmatic referred pain, and the stomach injury would not typically produce the classic left shoulder pain.